drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

   1 /**
   2  * Copyright (c) 2014 Raspberry Pi (Trading) Ltd. All rights reserved.
   3  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions, and the following disclaimer,
  10  *    without modification.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. The names of the above-listed copyright holders may not be used
  15  *    to endorse or promote products derived from this software without
  16  *    specific prior written permission.
  17  *
  18  * ALTERNATIVELY, this software may be distributed under the terms of the
  19  * GNU General Public License ("GPL") version 2, as published by the Free
  20  * Software Foundation.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  23  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  24  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  25  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  26  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  27  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  29  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  31  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  32  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include <linux/kernel.h>
  36 #include <linux/module.h>
  37 #include <linux/types.h>
  38 #include <linux/errno.h>
  39 #include <linux/cdev.h>
  40 #include <linux/fs.h>
  41 #include <linux/device.h>
  42 #include <linux/mm.h>
  43 #include <linux/highmem.h>
  44 #include <linux/pagemap.h>
  45 #include <linux/bug.h>
  46 #include <linux/semaphore.h>
  47 #include <linux/list.h>
  48 #include <linux/of.h>
  49 #include <linux/platform_device.h>
  50 #include <soc/bcm2835/raspberrypi-firmware.h>
  51
  52 #include "vchiq_core.h"
  53 #include "vchiq_ioctl.h"
  54 #include "vchiq_arm.h"
  55 #include "vchiq_debugfs.h"
  56 #include "vchiq_killable.h"
  57
  58 #define DEVICE_NAME "vchiq"
  59
  60 /* Override the default prefix, which would be vchiq_arm (from the filename) */
  61 #undef MODULE_PARAM_PREFIX
  62 #define MODULE_PARAM_PREFIX DEVICE_NAME "."
  63
  64 #define VCHIQ_MINOR 0
  65
  66 /* Some per-instance constants */
  67 #define MAX_COMPLETIONS 128
  68 #define MAX_SERVICES 64
  69 #define MAX_ELEMENTS 8
  70 #define MSG_QUEUE_SIZE 128
  71
  72 #define KEEPALIVE_VER 1
  73 #define KEEPALIVE_VER_MIN KEEPALIVE_VER
  74
  75 /* Run time control of log level, based on KERN_XXX level. */
  76 int vchiq_arm_log_level = VCHIQ_LOG_DEFAULT;
  77 int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
  78
  79 #define SUSPEND_TIMER_TIMEOUT_MS 100
  80 #define SUSPEND_RETRY_TIMER_TIMEOUT_MS 1000
  81
  82 #define VC_SUSPEND_NUM_OFFSET 3 /* number of values before idle which are -ve */
  83 static const char *const suspend_state_names[] = {
  84         "VC_SUSPEND_FORCE_CANCELED",
  85         "VC_SUSPEND_REJECTED",
  86         "VC_SUSPEND_FAILED",
  87         "VC_SUSPEND_IDLE",
  88         "VC_SUSPEND_REQUESTED",
  89         "VC_SUSPEND_IN_PROGRESS",
  90         "VC_SUSPEND_SUSPENDED"
  91 };
  92 #define VC_RESUME_NUM_OFFSET 1 /* number of values before idle which are -ve */
  93 static const char *const resume_state_names[] = {
  94         "VC_RESUME_FAILED",
  95         "VC_RESUME_IDLE",
  96         "VC_RESUME_REQUESTED",
  97         "VC_RESUME_IN_PROGRESS",
  98         "VC_RESUME_RESUMED"
  99 };
 100 /* The number of times we allow force suspend to timeout before actually
 101 ** _forcing_ suspend.  This is to cater for SW which fails to release vchiq
 102 ** correctly - we don't want to prevent ARM suspend indefinitely in this case.
 103 */
 104 #define FORCE_SUSPEND_FAIL_MAX 8
 105
 106 /* The time in ms allowed for videocore to go idle when force suspend has been
 107  * requested */
 108 #define FORCE_SUSPEND_TIMEOUT_MS 200
 109
 110
 111 static void suspend_timer_callback(unsigned long context);
 112
 113
 114 typedef struct user_service_struct {
 115         VCHIQ_SERVICE_T *service;
 116         void *userdata;
 117         VCHIQ_INSTANCE_T instance;
 118         char is_vchi;
 119         char dequeue_pending;
 120         char close_pending;
 121         int message_available_pos;
 122         int msg_insert;
 123         int msg_remove;
 124         struct semaphore insert_event;
 125         struct semaphore remove_event;
 126         struct semaphore close_event;
 127         VCHIQ_HEADER_T * msg_queue[MSG_QUEUE_SIZE];
 128 } USER_SERVICE_T;
 129
 130 struct bulk_waiter_node {
 131         struct bulk_waiter bulk_waiter;
 132         int pid;
 133         struct list_head list;
 134 };
 135
 136 struct vchiq_instance_struct {
 137         VCHIQ_STATE_T *state;
 138         VCHIQ_COMPLETION_DATA_T completions[MAX_COMPLETIONS];
 139         int completion_insert;
 140         int completion_remove;
 141         struct semaphore insert_event;
 142         struct semaphore remove_event;
 143         struct mutex completion_mutex;
 144
 145         int connected;
 146         int closing;
 147         int pid;
 148         int mark;
 149         int use_close_delivered;
 150         int trace;
 151
 152         struct list_head bulk_waiter_list;
 153         struct mutex bulk_waiter_list_mutex;
 154
 155         VCHIQ_DEBUGFS_NODE_T debugfs_node;
 156 };
 157
 158 typedef struct dump_context_struct {
 159         char __user *buf;
 160         size_t actual;
 161         size_t space;
 162         loff_t offset;
 163 } DUMP_CONTEXT_T;
 164
 165 static struct cdev    vchiq_cdev;
 166 static dev_t          vchiq_devid;
 167 static VCHIQ_STATE_T g_state;
 168 static struct class  *vchiq_class;
 169 static struct device *vchiq_dev;
 170 static DEFINE_SPINLOCK(msg_queue_spinlock);
 171
 172 static const char *const ioctl_names[] = {
 173         "CONNECT",
 174         "SHUTDOWN",
 175         "CREATE_SERVICE",
 176         "REMOVE_SERVICE",
 177         "QUEUE_MESSAGE",
 178         "QUEUE_BULK_TRANSMIT",
 179         "QUEUE_BULK_RECEIVE",
 180         "AWAIT_COMPLETION",
 181         "DEQUEUE_MESSAGE",
 182         "GET_CLIENT_ID",
 183         "GET_CONFIG",
 184         "CLOSE_SERVICE",
 185         "USE_SERVICE",
 186         "RELEASE_SERVICE",
 187         "SET_SERVICE_OPTION",
 188         "DUMP_PHYS_MEM",
 189         "LIB_VERSION",
 190         "CLOSE_DELIVERED"
 191 };
 192
 193 vchiq_static_assert(ARRAY_SIZE(ioctl_names) ==
 194                     (VCHIQ_IOC_MAX + 1));
 195
 196 static void
 197 dump_phys_mem(void *virt_addr, u32 num_bytes);
 198
 199 /****************************************************************************
 200 *
 201 *   add_completion
 202 *
 203 ***************************************************************************/
 204
 205 static VCHIQ_STATUS_T
 206 add_completion(VCHIQ_INSTANCE_T instance, VCHIQ_REASON_T reason,
 207         VCHIQ_HEADER_T *header, USER_SERVICE_T *user_service,
 208         void *bulk_userdata)
 209 {
 210         VCHIQ_COMPLETION_DATA_T *completion;
 211         int insert;
 212         DEBUG_INITIALISE(g_state.local)
 213
 214         insert = instance->completion_insert;
 215         while ((insert - instance->completion_remove) >= MAX_COMPLETIONS) {
 216                 /* Out of space - wait for the client */
 217                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 218                 vchiq_log_trace(vchiq_arm_log_level,
 219                         "add_completion - completion queue full");
 220                 DEBUG_COUNT(COMPLETION_QUEUE_FULL_COUNT);
 221                 if (down_interruptible(&instance->remove_event) != 0) {
 222                         vchiq_log_info(vchiq_arm_log_level,
 223                                 "service_callback interrupted");
 224                         return VCHIQ_RETRY;
 225                 } else if (instance->closing) {
 226                         vchiq_log_info(vchiq_arm_log_level,
 227                                 "service_callback closing");
 228                         return VCHIQ_SUCCESS;
 229                 }
 230                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 231         }
 232
 233         completion = &instance->completions[insert & (MAX_COMPLETIONS - 1)];
 234
 235         completion->header = header;
 236         completion->reason = reason;
 237         /* N.B. service_userdata is updated while processing AWAIT_COMPLETION */
 238         completion->service_userdata = user_service->service;
 239         completion->bulk_userdata = bulk_userdata;
 240
 241         if (reason == VCHIQ_SERVICE_CLOSED) {
 242                 /* Take an extra reference, to be held until
 243                    this CLOSED notification is delivered. */
 244                 lock_service(user_service->service);
 245                 if (instance->use_close_delivered)
 246                         user_service->close_pending = 1;
 247         }
 248
 249         /* A write barrier is needed here to ensure that the entire completion
 250                 record is written out before the insert point. */
 251         wmb();
 252
 253         if (reason == VCHIQ_MESSAGE_AVAILABLE)
 254                 user_service->message_available_pos = insert;
 255
 256         insert++;
 257         instance->completion_insert = insert;
 258
 259         up(&instance->insert_event);
 260
 261         return VCHIQ_SUCCESS;
 262 }
 263
 264 /****************************************************************************
 265 *
 266 *   service_callback
 267 *
 268 ***************************************************************************/
 269
 270 static VCHIQ_STATUS_T
 271 service_callback(VCHIQ_REASON_T reason, VCHIQ_HEADER_T *header,
 272         VCHIQ_SERVICE_HANDLE_T handle, void *bulk_userdata)
 273 {
 274         /* How do we ensure the callback goes to the right client?
 275         ** The service_user data points to a USER_SERVICE_T record containing
 276         ** the original callback and the user state structure, which contains a
 277         ** circular buffer for completion records.
 278         */
 279         USER_SERVICE_T *user_service;
 280         VCHIQ_SERVICE_T *service;
 281         VCHIQ_INSTANCE_T instance;
 282         bool skip_completion = false;
 283         DEBUG_INITIALISE(g_state.local)
 284
 285         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 286
 287         service = handle_to_service(handle);
 288         BUG_ON(!service);
 289         user_service = (USER_SERVICE_T *)service->base.userdata;
 290         instance = user_service->instance;
 291
 292         if (!instance || instance->closing)
 293                 return VCHIQ_SUCCESS;
 294
 295         vchiq_log_trace(vchiq_arm_log_level,
 296                 "service_callback - service %lx(%d,%p), reason %d, header %lx, "
 297                 "instance %lx, bulk_userdata %lx",
 298                 (unsigned long)user_service,
 299                 service->localport, user_service->userdata,
 300                 reason, (unsigned long)header,
 301                 (unsigned long)instance, (unsigned long)bulk_userdata);
 302
 303         if (header && user_service->is_vchi) {
 304                 spin_lock(&msg_queue_spinlock);
 305                 while (user_service->msg_insert ==
 306                         (user_service->msg_remove + MSG_QUEUE_SIZE)) {
 307                         spin_unlock(&msg_queue_spinlock);
 308                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 309                         DEBUG_COUNT(MSG_QUEUE_FULL_COUNT);
 310                         vchiq_log_trace(vchiq_arm_log_level,
 311                                 "service_callback - msg queue full");
 312                         /* If there is no MESSAGE_AVAILABLE in the completion
 313                         ** queue, add one
 314                         */
 315                         if ((user_service->message_available_pos -
 316                                 instance->completion_remove) < 0) {
 317                                 VCHIQ_STATUS_T status;
 318                                 vchiq_log_info(vchiq_arm_log_level,
 319                                         "Inserting extra MESSAGE_AVAILABLE");
 320                                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 321                                 status = add_completion(instance, reason,
 322                                         NULL, user_service, bulk_userdata);
 323                                 if (status != VCHIQ_SUCCESS) {
 324                                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 325                                         return status;
 326                                 }
 327                         }
 328
 329                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 330                         if (down_interruptible(&user_service->remove_event)
 331                                 != 0) {
 332                                 vchiq_log_info(vchiq_arm_log_level,
 333                                         "service_callback interrupted");
 334                                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 335                                 return VCHIQ_RETRY;
 336                         } else if (instance->closing) {
 337                                 vchiq_log_info(vchiq_arm_log_level,
 338                                         "service_callback closing");
 339                                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 340                                 return VCHIQ_ERROR;
 341                         }
 342                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 343                         spin_lock(&msg_queue_spinlock);
 344                 }
 345
 346                 user_service->msg_queue[user_service->msg_insert &
 347                         (MSG_QUEUE_SIZE - 1)] = header;
 348                 user_service->msg_insert++;
 349
 350                 /* If there is a thread waiting in DEQUEUE_MESSAGE, or if
 351                 ** there is a MESSAGE_AVAILABLE in the completion queue then
 352                 ** bypass the completion queue.
 353                 */
 354                 if (((user_service->message_available_pos -
 355                         instance->completion_remove) >= 0) ||
 356                         user_service->dequeue_pending) {
 357                         user_service->dequeue_pending = 0;
 358                         skip_completion = true;
 359                 }
 360
 361                 spin_unlock(&msg_queue_spinlock);
 362                 up(&user_service->insert_event);
 363
 364                 header = NULL;
 365         }
 366         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 367
 368         if (skip_completion)
 369                 return VCHIQ_SUCCESS;
 370
 371         return add_completion(instance, reason, header, user_service,
 372                 bulk_userdata);
 373 }
 374
 375 /****************************************************************************
 376 *
 377 *   user_service_free
 378 *
 379 ***************************************************************************/
 380 static void
 381 user_service_free(void *userdata)
 382 {
 383         kfree(userdata);
 384 }
 385
 386 /****************************************************************************
 387 *
 388 *   close_delivered
 389 *
 390 ***************************************************************************/
 391 static void close_delivered(USER_SERVICE_T *user_service)
 392 {
 393         vchiq_log_info(vchiq_arm_log_level,
 394                 "close_delivered(handle=%x)",
 395                 user_service->service->handle);
 396
 397         if (user_service->close_pending) {
 398                 /* Allow the underlying service to be culled */
 399                 unlock_service(user_service->service);
 400
 401                 /* Wake the user-thread blocked in close_ or remove_service */
 402                 up(&user_service->close_event);
 403
 404                 user_service->close_pending = 0;
 405         }
 406 }
 407
 408 struct vchiq_io_copy_callback_context {
 409         VCHIQ_ELEMENT_T *current_element;
 410         size_t current_element_offset;
 411         unsigned long elements_to_go;
 412         size_t current_offset;
 413 };
 414
 415 static ssize_t
 416 vchiq_ioc_copy_element_data(
 417         void *context,
 418         void *dest,
 419         size_t offset,
 420         size_t maxsize)
 421 {
 422         long res;
 423         size_t bytes_this_round;
 424         struct vchiq_io_copy_callback_context *copy_context =
 425                 (struct vchiq_io_copy_callback_context *)context;
 426
 427         if (offset != copy_context->current_offset)
 428                 return 0;
 429
 430         if (!copy_context->elements_to_go)
 431                 return 0;
 432
 433         /*
 434          * Complex logic here to handle the case of 0 size elements
 435          * in the middle of the array of elements.
 436          *
 437          * Need to skip over these 0 size elements.
 438          */
 439         while (1) {
 440                 bytes_this_round = min(copy_context->current_element->size -
 441                                        copy_context->current_element_offset,
 442                                        maxsize);
 443
 444                 if (bytes_this_round)
 445                         break;
 446
 447                 copy_context->elements_to_go--;
 448                 copy_context->current_element++;
 449                 copy_context->current_element_offset = 0;
 450
 451                 if (!copy_context->elements_to_go)
 452                         return 0;
 453         }
 454
 455         res = copy_from_user(dest,
 456                              copy_context->current_element->data +
 457                              copy_context->current_element_offset,
 458                              bytes_this_round);
 459
 460         if (res != 0)
 461                 return -EFAULT;
 462
 463         copy_context->current_element_offset += bytes_this_round;
 464         copy_context->current_offset += bytes_this_round;
 465
 466         /*
 467          * Check if done with current element, and if so advance to the next.
 468          */
 469         if (copy_context->current_element_offset ==
 470             copy_context->current_element->size) {
 471                 copy_context->elements_to_go--;
 472                 copy_context->current_element++;
 473                 copy_context->current_element_offset = 0;
 474         }
 475
 476         return bytes_this_round;
 477 }
 478
 479 /**************************************************************************
 480  *
 481  *   vchiq_ioc_queue_message
 482  *
 483  **************************************************************************/
 484 static VCHIQ_STATUS_T
 485 vchiq_ioc_queue_message(VCHIQ_SERVICE_HANDLE_T handle,
 486                         VCHIQ_ELEMENT_T *elements,
 487                         unsigned long count)
 488 {
 489         struct vchiq_io_copy_callback_context context;
 490         unsigned long i;
 491         size_t total_size = 0;
 492
 493         context.current_element = elements;
 494         context.current_element_offset = 0;
 495         context.elements_to_go = count;
 496         context.current_offset = 0;
 497
 498         for (i = 0; i < count; i++) {
 499                 if (!elements[i].data && elements[i].size != 0)
 500                         return -EFAULT;
 501
 502                 total_size += elements[i].size;
 503         }
 504
 505         return vchiq_queue_message(handle, vchiq_ioc_copy_element_data,
 506                                    &context, total_size);
 507 }
 508
 509 /****************************************************************************
 510 *
 511 *   vchiq_ioctl
 512 *
 513 ***************************************************************************/
 514 static long
 515 vchiq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 516 {
 517         VCHIQ_INSTANCE_T instance = file->private_data;
 518         VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
 519         VCHIQ_SERVICE_T *service = NULL;
 520         long ret = 0;
 521         int i, rc;
 522         DEBUG_INITIALISE(g_state.local)
 523
 524         vchiq_log_trace(vchiq_arm_log_level,
 525                 "vchiq_ioctl - instance %pK, cmd %s, arg %lx",
 526                 instance,
 527                 ((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
 528                 (_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
 529                 ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
 530
 531         switch (cmd) {
 532         case VCHIQ_IOC_SHUTDOWN:
 533                 if (!instance->connected)
 534                         break;
 535
 536                 /* Remove all services */
 537                 i = 0;
 538                 while ((service = next_service_by_instance(instance->state,
 539                         instance, &i)) != NULL) {
 540                         status = vchiq_remove_service(service->handle);
 541                         unlock_service(service);
 542                         if (status != VCHIQ_SUCCESS)
 543                                 break;
 544                 }
 545                 service = NULL;
 546
 547                 if (status == VCHIQ_SUCCESS) {
 548                         /* Wake the completion thread and ask it to exit */
 549                         instance->closing = 1;
 550                         up(&instance->insert_event);
 551                 }
 552
 553                 break;
 554
 555         case VCHIQ_IOC_CONNECT:
 556                 if (instance->connected) {
 557                         ret = -EINVAL;
 558                         break;
 559                 }
 560                 rc = mutex_lock_killable(&instance->state->mutex);
 561                 if (rc != 0) {
 562                         vchiq_log_error(vchiq_arm_log_level,
 563                                 "vchiq: connect: could not lock mutex for "
 564                                 "state %d: %d",
 565                                 instance->state->id, rc);
 566                         ret = -EINTR;
 567                         break;
 568                 }
 569                 status = vchiq_connect_internal(instance->state, instance);
 570                 mutex_unlock(&instance->state->mutex);
 571
 572                 if (status == VCHIQ_SUCCESS)
 573                         instance->connected = 1;
 574                 else
 575                         vchiq_log_error(vchiq_arm_log_level,
 576                                 "vchiq: could not connect: %d", status);
 577                 break;
 578
 579         case VCHIQ_IOC_CREATE_SERVICE: {
 580                 VCHIQ_CREATE_SERVICE_T args;
 581                 USER_SERVICE_T *user_service = NULL;
 582                 void *userdata;
 583                 int srvstate;
 584
 585                 if (copy_from_user
 586                          (&args, (const void __user *)arg,
 587                           sizeof(args)) != 0) {
 588                         ret = -EFAULT;
 589                         break;
 590                 }
 591
 592                 user_service = kmalloc(sizeof(USER_SERVICE_T), GFP_KERNEL);
 593                 if (!user_service) {
 594                         ret = -ENOMEM;
 595                         break;
 596                 }
 597
 598                 if (args.is_open) {
 599                         if (!instance->connected) {
 600                                 ret = -ENOTCONN;
 601                                 kfree(user_service);
 602                                 break;
 603                         }
 604                         srvstate = VCHIQ_SRVSTATE_OPENING;
 605                 } else {
 606                         srvstate =
 607                                  instance->connected ?
 608                                  VCHIQ_SRVSTATE_LISTENING :
 609                                  VCHIQ_SRVSTATE_HIDDEN;
 610                 }
 611
 612                 userdata = args.params.userdata;
 613                 args.params.callback = service_callback;
 614                 args.params.userdata = user_service;
 615                 service = vchiq_add_service_internal(
 616                                 instance->state,
 617                                 &args.params, srvstate,
 618                                 instance, user_service_free);
 619
 620                 if (service != NULL) {
 621                         user_service->service = service;
 622                         user_service->userdata = userdata;
 623                         user_service->instance = instance;
 624                         user_service->is_vchi = (args.is_vchi != 0);
 625                         user_service->dequeue_pending = 0;
 626                         user_service->close_pending = 0;
 627                         user_service->message_available_pos =
 628                                 instance->completion_remove - 1;
 629                         user_service->msg_insert = 0;
 630                         user_service->msg_remove = 0;
 631                         sema_init(&user_service->insert_event, 0);
 632                         sema_init(&user_service->remove_event, 0);
 633                         sema_init(&user_service->close_event, 0);
 634
 635                         if (args.is_open) {
 636                                 status = vchiq_open_service_internal
 637                                         (service, instance->pid);
 638                                 if (status != VCHIQ_SUCCESS) {
 639                                         vchiq_remove_service(service->handle);
 640                                         service = NULL;
 641                                         ret = (status == VCHIQ_RETRY) ?
 642                                                 -EINTR : -EIO;
 643                                         break;
 644                                 }
 645                         }
 646
 647                         if (copy_to_user((void __user *)
 648                                 &(((VCHIQ_CREATE_SERVICE_T __user *)
 649                                         arg)->handle),
 650                                 (const void *)&service->handle,
 651                                 sizeof(service->handle)) != 0) {
 652                                 ret = -EFAULT;
 653                                 vchiq_remove_service(service->handle);
 654                         }
 655
 656                         service = NULL;
 657                 } else {
 658                         ret = -EEXIST;
 659                         kfree(user_service);
 660                 }
 661         } break;
 662
 663         case VCHIQ_IOC_CLOSE_SERVICE: {
 664                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 665
 666                 service = find_service_for_instance(instance, handle);
 667                 if (service != NULL) {
 668                         USER_SERVICE_T *user_service =
 669                                 (USER_SERVICE_T *)service->base.userdata;
 670                         /* close_pending is false on first entry, and when the
 671                            wait in vchiq_close_service has been interrupted. */
 672                         if (!user_service->close_pending) {
 673                                 status = vchiq_close_service(service->handle);
 674                                 if (status != VCHIQ_SUCCESS)
 675                                         break;
 676                         }
 677
 678                         /* close_pending is true once the underlying service
 679                            has been closed until the client library calls the
 680                            CLOSE_DELIVERED ioctl, signalling close_event. */
 681                         if (user_service->close_pending &&
 682                                 down_interruptible(&user_service->close_event))
 683                                 status = VCHIQ_RETRY;
 684                 }
 685                 else
 686                         ret = -EINVAL;
 687         } break;
 688
 689         case VCHIQ_IOC_REMOVE_SERVICE: {
 690                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 691
 692                 service = find_service_for_instance(instance, handle);
 693                 if (service != NULL) {
 694                         USER_SERVICE_T *user_service =
 695                                 (USER_SERVICE_T *)service->base.userdata;
 696                         /* close_pending is false on first entry, and when the
 697                            wait in vchiq_close_service has been interrupted. */
 698                         if (!user_service->close_pending) {
 699                                 status = vchiq_remove_service(service->handle);
 700                                 if (status != VCHIQ_SUCCESS)
 701                                         break;
 702                         }
 703
 704                         /* close_pending is true once the underlying service
 705                            has been closed until the client library calls the
 706                            CLOSE_DELIVERED ioctl, signalling close_event. */
 707                         if (user_service->close_pending &&
 708                                 down_interruptible(&user_service->close_event))
 709                                 status = VCHIQ_RETRY;
 710                 }
 711                 else
 712                         ret = -EINVAL;
 713         } break;
 714
 715         case VCHIQ_IOC_USE_SERVICE:
 716         case VCHIQ_IOC_RELEASE_SERVICE: {
 717                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 718
 719                 service = find_service_for_instance(instance, handle);
 720                 if (service != NULL) {
 721                         status = (cmd == VCHIQ_IOC_USE_SERVICE) ?
 722                                 vchiq_use_service_internal(service) :
 723                                 vchiq_release_service_internal(service);
 724                         if (status != VCHIQ_SUCCESS) {
 725                                 vchiq_log_error(vchiq_susp_log_level,
 726                                         "%s: cmd %s returned error %d for "
 727                                         "service %c%c%c%c:%03d",
 728                                         __func__,
 729                                         (cmd == VCHIQ_IOC_USE_SERVICE) ?
 730                                                 "VCHIQ_IOC_USE_SERVICE" :
 731                                                 "VCHIQ_IOC_RELEASE_SERVICE",
 732                                         status,
 733                                         VCHIQ_FOURCC_AS_4CHARS(
 734                                                 service->base.fourcc),
 735                                         service->client_id);
 736                                 ret = -EINVAL;
 737                         }
 738                 } else
 739                         ret = -EINVAL;
 740         } break;
 741
 742         case VCHIQ_IOC_QUEUE_MESSAGE: {
 743                 VCHIQ_QUEUE_MESSAGE_T args;
 744                 if (copy_from_user
 745                          (&args, (const void __user *)arg,
 746                           sizeof(args)) != 0) {
 747                         ret = -EFAULT;
 748                         break;
 749                 }
 750
 751                 service = find_service_for_instance(instance, args.handle);
 752
 753                 if ((service != NULL) && (args.count <= MAX_ELEMENTS)) {
 754                         /* Copy elements into kernel space */
 755                         VCHIQ_ELEMENT_T elements[MAX_ELEMENTS];
 756                         if (copy_from_user(elements, args.elements,
 757                                 args.count * sizeof(VCHIQ_ELEMENT_T)) == 0)
 758                                 status = vchiq_ioc_queue_message
 759                                         (args.handle,
 760                                         elements, args.count);
 761                         else
 762                                 ret = -EFAULT;
 763                 } else {
 764                         ret = -EINVAL;
 765                 }
 766         } break;
 767
 768         case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
 769         case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
 770                 VCHIQ_QUEUE_BULK_TRANSFER_T args;
 771                 struct bulk_waiter_node *waiter = NULL;
 772                 VCHIQ_BULK_DIR_T dir =
 773                         (cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
 774                         VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
 775
 776                 if (copy_from_user
 777                         (&args, (const void __user *)arg,
 778                         sizeof(args)) != 0) {
 779                         ret = -EFAULT;
 780                         break;
 781                 }
 782
 783                 service = find_service_for_instance(instance, args.handle);
 784                 if (!service) {
 785                         ret = -EINVAL;
 786                         break;
 787                 }
 788
 789                 if (args.mode == VCHIQ_BULK_MODE_BLOCKING) {
 790                         waiter = kzalloc(sizeof(struct bulk_waiter_node),
 791                                 GFP_KERNEL);
 792                         if (!waiter) {
 793                                 ret = -ENOMEM;
 794                                 break;
 795                         }
 796                         args.userdata = &waiter->bulk_waiter;
 797                 } else if (args.mode == VCHIQ_BULK_MODE_WAITING) {
 798                         struct list_head *pos;
 799                         mutex_lock(&instance->bulk_waiter_list_mutex);
 800                         list_for_each(pos, &instance->bulk_waiter_list) {
 801                                 if (list_entry(pos, struct bulk_waiter_node,
 802                                         list)->pid == current->pid) {
 803                                         waiter = list_entry(pos,
 804                                                 struct bulk_waiter_node,
 805                                                 list);
 806                                         list_del(pos);
 807                                         break;
 808                                 }
 809
 810                         }
 811                         mutex_unlock(&instance->bulk_waiter_list_mutex);
 812                         if (!waiter) {
 813                                 vchiq_log_error(vchiq_arm_log_level,
 814                                         "no bulk_waiter found for pid %d",
 815                                         current->pid);
 816                                 ret = -ESRCH;
 817                                 break;
 818                         }
 819                         vchiq_log_info(vchiq_arm_log_level,
 820                                 "found bulk_waiter %pK for pid %d", waiter,
 821                                 current->pid);
 822                         args.userdata = &waiter->bulk_waiter;
 823                 }
 824                 status = vchiq_bulk_transfer
 825                         (args.handle,
 826                          VCHI_MEM_HANDLE_INVALID,
 827                          args.data, args.size,
 828                          args.userdata, args.mode,
 829                          dir);
 830                 if (!waiter)
 831                         break;
 832                 if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
 833                         !waiter->bulk_waiter.bulk) {
 834                         if (waiter->bulk_waiter.bulk) {
 835                                 /* Cancel the signal when the transfer
 836                                 ** completes. */
 837                                 spin_lock(&bulk_waiter_spinlock);
 838                                 waiter->bulk_waiter.bulk->userdata = NULL;
 839                                 spin_unlock(&bulk_waiter_spinlock);
 840                         }
 841                         kfree(waiter);
 842                 } else {
 843                         const VCHIQ_BULK_MODE_T mode_waiting =
 844                                 VCHIQ_BULK_MODE_WAITING;
 845                         waiter->pid = current->pid;
 846                         mutex_lock(&instance->bulk_waiter_list_mutex);
 847                         list_add(&waiter->list, &instance->bulk_waiter_list);
 848                         mutex_unlock(&instance->bulk_waiter_list_mutex);
 849                         vchiq_log_info(vchiq_arm_log_level,
 850                                 "saved bulk_waiter %pK for pid %d",
 851                                 waiter, current->pid);
 852
 853                         if (copy_to_user((void __user *)
 854                                 &(((VCHIQ_QUEUE_BULK_TRANSFER_T __user *)
 855                                         arg)->mode),
 856                                 (const void *)&mode_waiting,
 857                                 sizeof(mode_waiting)) != 0)
 858                                 ret = -EFAULT;
 859                 }
 860         } break;
 861
 862         case VCHIQ_IOC_AWAIT_COMPLETION: {
 863                 VCHIQ_AWAIT_COMPLETION_T args;
 864
 865                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 866                 if (!instance->connected) {
 867                         ret = -ENOTCONN;
 868                         break;
 869                 }
 870
 871                 if (copy_from_user(&args, (const void __user *)arg,
 872                         sizeof(args)) != 0) {
 873                         ret = -EFAULT;
 874                         break;
 875                 }
 876
 877                 mutex_lock(&instance->completion_mutex);
 878
 879                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 880                 while ((instance->completion_remove ==
 881                         instance->completion_insert)
 882                         && !instance->closing) {
 883                         int rc;
 884                         DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 885                         mutex_unlock(&instance->completion_mutex);
 886                         rc = down_interruptible(&instance->insert_event);
 887                         mutex_lock(&instance->completion_mutex);
 888                         if (rc != 0) {
 889                                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 890                                 vchiq_log_info(vchiq_arm_log_level,
 891                                         "AWAIT_COMPLETION interrupted");
 892                                 ret = -EINTR;
 893                                 break;
 894                         }
 895                 }
 896                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 897
 898                 if (ret == 0) {
 899                         int msgbufcount = args.msgbufcount;
 900                         int remove = instance->completion_remove;
 901
 902                         for (ret = 0; ret < args.count; ret++) {
 903                                 VCHIQ_COMPLETION_DATA_T *completion;
 904                                 VCHIQ_SERVICE_T *service;
 905                                 USER_SERVICE_T *user_service;
 906                                 VCHIQ_HEADER_T *header;
 907
 908                                 if (remove == instance->completion_insert)
 909                                         break;
 910
 911                                 completion = &instance->completions[
 912                                         remove & (MAX_COMPLETIONS - 1)];
 913
 914                                 /*
 915                                  * A read memory barrier is needed to stop
 916                                  * prefetch of a stale completion record
 917                                  */
 918                                 rmb();
 919
 920                                 service = completion->service_userdata;
 921                                 user_service = service->base.userdata;
 922                                 completion->service_userdata =
 923                                         user_service->userdata;
 924
 925                                 header = completion->header;
 926                                 if (header) {
 927                                         void __user *msgbuf;
 928                                         int msglen;
 929
 930                                         msglen = header->size +
 931                                                 sizeof(VCHIQ_HEADER_T);
 932                                         /* This must be a VCHIQ-style service */
 933                                         if (args.msgbufsize < msglen) {
 934                                                 vchiq_log_error(
 935                                                         vchiq_arm_log_level,
 936                                                         "header %pK: msgbufsize %x < msglen %x",
 937                                                         header, args.msgbufsize,
 938                                                         msglen);
 939                                                 WARN(1, "invalid message "
 940                                                         "size\n");
 941                                                 if (ret == 0)
 942                                                         ret = -EMSGSIZE;
 943                                                 break;
 944                                         }
 945                                         if (msgbufcount <= 0)
 946                                                 /* Stall here for lack of a
 947                                                 ** buffer for the message. */
 948                                                 break;
 949                                         /* Get the pointer from user space */
 950                                         msgbufcount--;
 951                                         if (copy_from_user(&msgbuf,
 952                                                 (const void __user *)
 953                                                 &args.msgbufs[msgbufcount],
 954                                                 sizeof(msgbuf)) != 0) {
 955                                                 if (ret == 0)
 956                                                         ret = -EFAULT;
 957                                                 break;
 958                                         }
 959
 960                                         /* Copy the message to user space */
 961                                         if (copy_to_user(msgbuf, header,
 962                                                 msglen) != 0) {
 963                                                 if (ret == 0)
 964                                                         ret = -EFAULT;
 965                                                 break;
 966                                         }
 967
 968                                         /* Now it has been copied, the message
 969                                         ** can be released. */
 970                                         vchiq_release_message(service->handle,
 971                                                 header);
 972
 973                                         /* The completion must point to the
 974                                         ** msgbuf. */
 975                                         completion->header = msgbuf;
 976                                 }
 977
 978                                 if ((completion->reason ==
 979                                         VCHIQ_SERVICE_CLOSED) &&
 980                                         !instance->use_close_delivered)
 981                                         unlock_service(service);
 982
 983                                 if (copy_to_user((void __user *)(
 984                                         (size_t)args.buf +
 985                                         ret * sizeof(VCHIQ_COMPLETION_DATA_T)),
 986                                         completion,
 987                                         sizeof(VCHIQ_COMPLETION_DATA_T)) != 0) {
 988                                                 if (ret == 0)
 989                                                         ret = -EFAULT;
 990                                         break;
 991                                 }
 992
 993                                 /*
 994                                  * Ensure that the above copy has completed
 995                                  * before advancing the remove pointer.
 996                                  */
 997                                 mb();
 998                                 remove++;
 999                                 instance->completion_remove = remove;
1000                         }
1001
1002                         if (msgbufcount != args.msgbufcount) {
1003                                 if (copy_to_user((void __user *)
1004                                         &((VCHIQ_AWAIT_COMPLETION_T *)arg)->
1005                                                 msgbufcount,
1006                                         &msgbufcount,
1007                                         sizeof(msgbufcount)) != 0) {
1008                                         ret = -EFAULT;
1009                                 }
1010                         }
1011                 }
1012
1013                 if (ret != 0)
1014                         up(&instance->remove_event);
1015                 mutex_unlock(&instance->completion_mutex);
1016                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
1017         } break;
1018
1019         case VCHIQ_IOC_DEQUEUE_MESSAGE: {
1020                 VCHIQ_DEQUEUE_MESSAGE_T args;
1021                 USER_SERVICE_T *user_service;
1022                 VCHIQ_HEADER_T *header;
1023
1024                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
1025                 if (copy_from_user
1026                          (&args, (const void __user *)arg,
1027                           sizeof(args)) != 0) {
1028                         ret = -EFAULT;
1029                         break;
1030                 }
1031                 service = find_service_for_instance(instance, args.handle);
1032                 if (!service) {
1033                         ret = -EINVAL;
1034                         break;
1035                 }
1036                 user_service = (USER_SERVICE_T *)service->base.userdata;
1037                 if (user_service->is_vchi == 0) {
1038                         ret = -EINVAL;
1039                         break;
1040                 }
1041
1042                 spin_lock(&msg_queue_spinlock);
1043                 if (user_service->msg_remove == user_service->msg_insert) {
1044                         if (!args.blocking) {
1045                                 spin_unlock(&msg_queue_spinlock);
1046                                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
1047                                 ret = -EWOULDBLOCK;
1048                                 break;
1049                         }
1050                         user_service->dequeue_pending = 1;
1051                         do {
1052                                 spin_unlock(&msg_queue_spinlock);
1053                                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
1054                                 if (down_interruptible(
1055                                         &user_service->insert_event) != 0) {
1056                                         vchiq_log_info(vchiq_arm_log_level,
1057                                                 "DEQUEUE_MESSAGE interrupted");
1058                                         ret = -EINTR;
1059                                         break;
1060                                 }
1061                                 spin_lock(&msg_queue_spinlock);
1062                         } while (user_service->msg_remove ==
1063                                 user_service->msg_insert);
1064
1065                         if (ret)
1066                                 break;
1067                 }
1068
1069                 BUG_ON((int)(user_service->msg_insert -
1070                         user_service->msg_remove) < 0);
1071
1072                 header = user_service->msg_queue[user_service->msg_remove &
1073                         (MSG_QUEUE_SIZE - 1)];
1074                 user_service->msg_remove++;
1075                 spin_unlock(&msg_queue_spinlock);
1076
1077                 up(&user_service->remove_event);
1078                 if (header == NULL)
1079                         ret = -ENOTCONN;
1080                 else if (header->size <= args.bufsize) {
1081                         /* Copy to user space if msgbuf is not NULL */
1082                         if ((args.buf == NULL) ||
1083                                 (copy_to_user((void __user *)args.buf,
1084                                 header->data,
1085                                 header->size) == 0)) {
1086                                 ret = header->size;
1087                                 vchiq_release_message(
1088                                         service->handle,
1089                                         header);
1090                         } else
1091                                 ret = -EFAULT;
1092                 } else {
1093                         vchiq_log_error(vchiq_arm_log_level,
1094                                 "header %pK: bufsize %x < size %x",
1095                                 header, args.bufsize, header->size);
1096                         WARN(1, "invalid size\n");
1097                         ret = -EMSGSIZE;
1098                 }
1099                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
1100         } break;
1101
1102         case VCHIQ_IOC_GET_CLIENT_ID: {
1103                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
1104
1105                 ret = vchiq_get_client_id(handle);
1106         } break;
1107
1108         case VCHIQ_IOC_GET_CONFIG: {
1109                 VCHIQ_GET_CONFIG_T args;
1110                 VCHIQ_CONFIG_T config;
1111
1112                 if (copy_from_user(&args, (const void __user *)arg,
1113                         sizeof(args)) != 0) {
1114                         ret = -EFAULT;
1115                         break;
1116                 }
1117                 if (args.config_size > sizeof(config)) {
1118                         ret = -EINVAL;
1119                         break;
1120                 }
1121                 status = vchiq_get_config(instance, args.config_size, &config);
1122                 if (status == VCHIQ_SUCCESS) {
1123                         if (copy_to_user((void __user *)args.pconfig,
1124                                     &config, args.config_size) != 0) {
1125                                 ret = -EFAULT;
1126                                 break;
1127                         }
1128                 }
1129         } break;
1130
1131         case VCHIQ_IOC_SET_SERVICE_OPTION: {
1132                 VCHIQ_SET_SERVICE_OPTION_T args;
1133
1134                 if (copy_from_user(
1135                         &args, (const void __user *)arg,
1136                         sizeof(args)) != 0) {
1137                         ret = -EFAULT;
1138                         break;
1139                 }
1140
1141                 service = find_service_for_instance(instance, args.handle);
1142                 if (!service) {
1143                         ret = -EINVAL;
1144                         break;
1145                 }
1146
1147                 status = vchiq_set_service_option(
1148                                 args.handle, args.option, args.value);
1149         } break;
1150
1151         case VCHIQ_IOC_DUMP_PHYS_MEM: {
1152                 VCHIQ_DUMP_MEM_T  args;
1153
1154                 if (copy_from_user
1155                          (&args, (const void __user *)arg,
1156                           sizeof(args)) != 0) {
1157                         ret = -EFAULT;
1158                         break;
1159                 }
1160                 dump_phys_mem(args.virt_addr, args.num_bytes);
1161         } break;
1162
1163         case VCHIQ_IOC_LIB_VERSION: {
1164                 unsigned int lib_version = (unsigned int)arg;
1165
1166                 if (lib_version < VCHIQ_VERSION_MIN)
1167                         ret = -EINVAL;
1168                 else if (lib_version >= VCHIQ_VERSION_CLOSE_DELIVERED)
1169                         instance->use_close_delivered = 1;
1170         } break;
1171
1172         case VCHIQ_IOC_CLOSE_DELIVERED: {
1173                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
1174
1175                 service = find_closed_service_for_instance(instance, handle);
1176                 if (service != NULL) {
1177                         USER_SERVICE_T *user_service =
1178                                 (USER_SERVICE_T *)service->base.userdata;
1179                         close_delivered(user_service);
1180                 }
1181                 else
1182                         ret = -EINVAL;
1183         } break;
1184
1185         default:
1186                 ret = -ENOTTY;
1187                 break;
1188         }
1189
1190         if (service)
1191                 unlock_service(service);
1192
1193         if (ret == 0) {
1194                 if (status == VCHIQ_ERROR)
1195                         ret = -EIO;
1196                 else if (status == VCHIQ_RETRY)
1197                         ret = -EINTR;
1198         }
1199
1200         if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
1201                 (ret != -EWOULDBLOCK))
1202                 vchiq_log_info(vchiq_arm_log_level,
1203                         "  ioctl instance %lx, cmd %s -> status %d, %ld",
1204                         (unsigned long)instance,
1205                         (_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1206                                 ioctl_names[_IOC_NR(cmd)] :
1207                                 "<invalid>",
1208                         status, ret);
1209         else
1210                 vchiq_log_trace(vchiq_arm_log_level,
1211                         "  ioctl instance %lx, cmd %s -> status %d, %ld",
1212                         (unsigned long)instance,
1213                         (_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1214                                 ioctl_names[_IOC_NR(cmd)] :
1215                                 "<invalid>",
1216                         status, ret);
1217
1218         return ret;
1219 }
1220
1221 /****************************************************************************
1222 *
1223 *   vchiq_open
1224 *
1225 ***************************************************************************/
1226
1227 static int
1228 vchiq_open(struct inode *inode, struct file *file)
1229 {
1230         int dev = iminor(inode) & 0x0f;
1231         vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
1232         switch (dev) {
1233         case VCHIQ_MINOR: {
1234                 int ret;
1235                 VCHIQ_STATE_T *state = vchiq_get_state();
1236                 VCHIQ_INSTANCE_T instance;
1237
1238                 if (!state) {
1239                         vchiq_log_error(vchiq_arm_log_level,
1240                                 "vchiq has no connection to VideoCore");
1241                         return -ENOTCONN;
1242                 }
1243
1244                 instance = kzalloc(sizeof(*instance), GFP_KERNEL);
1245                 if (!instance)
1246                         return -ENOMEM;
1247
1248                 instance->state = state;
1249                 instance->pid = current->tgid;
1250
1251                 ret = vchiq_debugfs_add_instance(instance);
1252                 if (ret != 0) {
1253                         kfree(instance);
1254                         return ret;
1255                 }
1256
1257                 sema_init(&instance->insert_event, 0);
1258                 sema_init(&instance->remove_event, 0);
1259                 mutex_init(&instance->completion_mutex);
1260                 mutex_init(&instance->bulk_waiter_list_mutex);
1261                 INIT_LIST_HEAD(&instance->bulk_waiter_list);
1262
1263                 file->private_data = instance;
1264         } break;
1265
1266         default:
1267                 vchiq_log_error(vchiq_arm_log_level,
1268                         "Unknown minor device: %d", dev);
1269                 return -ENXIO;
1270         }
1271
1272         return 0;
1273 }
1274
1275 /****************************************************************************
1276 *
1277 *   vchiq_release
1278 *
1279 ***************************************************************************/
1280
1281 static int
1282 vchiq_release(struct inode *inode, struct file *file)
1283 {
1284         int dev = iminor(inode) & 0x0f;
1285         int ret = 0;
1286         switch (dev) {
1287         case VCHIQ_MINOR: {
1288                 VCHIQ_INSTANCE_T instance = file->private_data;
1289                 VCHIQ_STATE_T *state = vchiq_get_state();
1290                 VCHIQ_SERVICE_T *service;
1291                 int i;
1292
1293                 vchiq_log_info(vchiq_arm_log_level,
1294                         "vchiq_release: instance=%lx",
1295                         (unsigned long)instance);
1296
1297                 if (!state) {
1298                         ret = -EPERM;
1299                         goto out;
1300                 }
1301
1302                 /* Ensure videocore is awake to allow termination. */
1303                 vchiq_use_internal(instance->state, NULL,
1304                                 USE_TYPE_VCHIQ);
1305
1306                 mutex_lock(&instance->completion_mutex);
1307
1308                 /* Wake the completion thread and ask it to exit */
1309                 instance->closing = 1;
1310                 up(&instance->insert_event);
1311
1312                 mutex_unlock(&instance->completion_mutex);
1313
1314                 /* Wake the slot handler if the completion queue is full. */
1315                 up(&instance->remove_event);
1316
1317                 /* Mark all services for termination... */
1318                 i = 0;
1319                 while ((service = next_service_by_instance(state, instance,
1320                         &i)) != NULL) {
1321                         USER_SERVICE_T *user_service = service->base.userdata;
1322
1323                         /* Wake the slot handler if the msg queue is full. */
1324                         up(&user_service->remove_event);
1325
1326                         vchiq_terminate_service_internal(service);
1327                         unlock_service(service);
1328                 }
1329
1330                 /* ...and wait for them to die */
1331                 i = 0;
1332                 while ((service = next_service_by_instance(state, instance, &i))
1333                         != NULL) {
1334                         USER_SERVICE_T *user_service = service->base.userdata;
1335
1336                         down(&service->remove_event);
1337
1338                         BUG_ON(service->srvstate != VCHIQ_SRVSTATE_FREE);
1339
1340                         spin_lock(&msg_queue_spinlock);
1341
1342                         while (user_service->msg_remove !=
1343                                 user_service->msg_insert) {
1344                                 VCHIQ_HEADER_T *header = user_service->
1345                                         msg_queue[user_service->msg_remove &
1346                                                 (MSG_QUEUE_SIZE - 1)];
1347                                 user_service->msg_remove++;
1348                                 spin_unlock(&msg_queue_spinlock);
1349
1350                                 if (header)
1351                                         vchiq_release_message(
1352                                                 service->handle,
1353                                                 header);
1354                                 spin_lock(&msg_queue_spinlock);
1355                         }
1356
1357                         spin_unlock(&msg_queue_spinlock);
1358
1359                         unlock_service(service);
1360                 }
1361
1362                 /* Release any closed services */
1363                 while (instance->completion_remove !=
1364                         instance->completion_insert) {
1365                         VCHIQ_COMPLETION_DATA_T *completion;
1366                         VCHIQ_SERVICE_T *service;
1367                         completion = &instance->completions[
1368                                 instance->completion_remove &
1369                                 (MAX_COMPLETIONS - 1)];
1370                         service = completion->service_userdata;
1371                         if (completion->reason == VCHIQ_SERVICE_CLOSED)
1372                         {
1373                                 USER_SERVICE_T *user_service =
1374                                         service->base.userdata;
1375
1376                                 /* Wake any blocked user-thread */
1377                                 if (instance->use_close_delivered)
1378                                         up(&user_service->close_event);
1379                                 unlock_service(service);
1380                         }
1381                         instance->completion_remove++;
1382                 }
1383
1384                 /* Release the PEER service count. */
1385                 vchiq_release_internal(instance->state, NULL);
1386
1387                 {
1388                         struct list_head *pos, *next;
1389                         list_for_each_safe(pos, next,
1390                                 &instance->bulk_waiter_list) {
1391                                 struct bulk_waiter_node *waiter;
1392                                 waiter = list_entry(pos,
1393                                         struct bulk_waiter_node,
1394                                         list);
1395                                 list_del(pos);
1396                                 vchiq_log_info(vchiq_arm_log_level,
1397                                         "bulk_waiter - cleaned up %pK for pid %d",
1398                                         waiter, waiter->pid);
1399                                 kfree(waiter);
1400                         }
1401                 }
1402
1403                 vchiq_debugfs_remove_instance(instance);
1404
1405                 kfree(instance);
1406                 file->private_data = NULL;
1407         } break;
1408
1409         default:
1410                 vchiq_log_error(vchiq_arm_log_level,
1411                         "Unknown minor device: %d", dev);
1412                 ret = -ENXIO;
1413         }
1414
1415 out:
1416         return ret;
1417 }
1418
1419 /****************************************************************************
1420 *
1421 *   vchiq_dump
1422 *
1423 ***************************************************************************/
1424
1425 void
1426 vchiq_dump(void *dump_context, const char *str, int len)
1427 {
1428         DUMP_CONTEXT_T *context = (DUMP_CONTEXT_T *)dump_context;
1429
1430         if (context->actual < context->space) {
1431                 int copy_bytes;
1432                 if (context->offset > 0) {
1433                         int skip_bytes = min(len, (int)context->offset);
1434                         str += skip_bytes;
1435                         len -= skip_bytes;
1436                         context->offset -= skip_bytes;
1437                         if (context->offset > 0)
1438                                 return;
1439                 }
1440                 copy_bytes = min(len, (int)(context->space - context->actual));
1441                 if (copy_bytes == 0)
1442                         return;
1443                 if (copy_to_user(context->buf + context->actual, str,
1444                         copy_bytes))
1445                         context->actual = -EFAULT;
1446                 context->actual += copy_bytes;
1447                 len -= copy_bytes;
1448
1449                 /* If tne terminating NUL is included in the length, then it
1450                 ** marks the end of a line and should be replaced with a
1451                 ** carriage return. */
1452                 if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
1453                         char cr = '\n';
1454                         if (copy_to_user(context->buf + context->actual - 1,
1455                                 &cr, 1))
1456                                 context->actual = -EFAULT;
1457                 }
1458         }
1459 }
1460
1461 /****************************************************************************
1462 *
1463 *   vchiq_dump_platform_instance_state
1464 *
1465 ***************************************************************************/
1466
1467 void
1468 vchiq_dump_platform_instances(void *dump_context)
1469 {
1470         VCHIQ_STATE_T *state = vchiq_get_state();
1471         char buf[80];
1472         int len;
1473         int i;
1474
1475         /* There is no list of instances, so instead scan all services,
1476                 marking those that have been dumped. */
1477
1478         for (i = 0; i < state->unused_service; i++) {
1479                 VCHIQ_SERVICE_T *service = state->services[i];
1480                 VCHIQ_INSTANCE_T instance;
1481
1482                 if (service && (service->base.callback == service_callback)) {
1483                         instance = service->instance;
1484                         if (instance)
1485                                 instance->mark = 0;
1486                 }
1487         }
1488
1489         for (i = 0; i < state->unused_service; i++) {
1490                 VCHIQ_SERVICE_T *service = state->services[i];
1491                 VCHIQ_INSTANCE_T instance;
1492
1493                 if (service && (service->base.callback == service_callback)) {
1494                         instance = service->instance;
1495                         if (instance && !instance->mark) {
1496                                 len = snprintf(buf, sizeof(buf),
1497                                         "Instance %pK: pid %d,%s completions %d/%d",
1498                                         instance, instance->pid,
1499                                         instance->connected ? " connected, " :
1500                                                 "",
1501                                         instance->completion_insert -
1502                                                 instance->completion_remove,
1503                                         MAX_COMPLETIONS);
1504
1505                                 vchiq_dump(dump_context, buf, len + 1);
1506
1507                                 instance->mark = 1;
1508                         }
1509                 }
1510         }
1511 }
1512
1513 /****************************************************************************
1514 *
1515 *   vchiq_dump_platform_service_state
1516 *
1517 ***************************************************************************/
1518
1519 void
1520 vchiq_dump_platform_service_state(void *dump_context, VCHIQ_SERVICE_T *service)
1521 {
1522         USER_SERVICE_T *user_service = (USER_SERVICE_T *)service->base.userdata;
1523         char buf[80];
1524         int len;
1525
1526         len = snprintf(buf, sizeof(buf), "  instance %pK", service->instance);
1527
1528         if ((service->base.callback == service_callback) &&
1529                 user_service->is_vchi) {
1530                 len += snprintf(buf + len, sizeof(buf) - len,
1531                         ", %d/%d messages",
1532                         user_service->msg_insert - user_service->msg_remove,
1533                         MSG_QUEUE_SIZE);
1534
1535                 if (user_service->dequeue_pending)
1536                         len += snprintf(buf + len, sizeof(buf) - len,
1537                                 " (dequeue pending)");
1538         }
1539
1540         vchiq_dump(dump_context, buf, len + 1);
1541 }
1542
1543 /****************************************************************************
1544 *
1545 *   dump_user_mem
1546 *
1547 ***************************************************************************/
1548
1549 static void
1550 dump_phys_mem(void *virt_addr, u32 num_bytes)
1551 {
1552         int            rc;
1553         u8            *end_virt_addr = virt_addr + num_bytes;
1554         int            num_pages;
1555         int            offset;
1556         int            end_offset;
1557         int            page_idx;
1558         int            prev_idx;
1559         struct page   *page;
1560         struct page  **pages;
1561         u8            *kmapped_virt_ptr;
1562
1563         /* Align virtAddr and endVirtAddr to 16 byte boundaries. */
1564
1565         virt_addr = (void *)((unsigned long)virt_addr & ~0x0fuL);
1566         end_virt_addr = (void *)(((unsigned long)end_virt_addr + 15uL) &
1567                 ~0x0fuL);
1568
1569         offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
1570         end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
1571
1572         num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
1573
1574         pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1575         if (pages == NULL) {
1576                 vchiq_log_error(vchiq_arm_log_level,
1577                         "Unable to allocation memory for %d pages\n",
1578                         num_pages);
1579                 return;
1580         }
1581
1582         down_read(&current->mm->mmap_sem);
1583         rc = get_user_pages(
1584                 (unsigned long)virt_addr, /* start */
1585                 num_pages,                /* len */
1586                 0,                        /* gup_flags */
1587                 pages,                    /* pages (array of page pointers) */
1588                 NULL);                    /* vmas */
1589         up_read(&current->mm->mmap_sem);
1590
1591         prev_idx = -1;
1592         page = NULL;
1593
1594         if (rc < 0) {
1595                 vchiq_log_error(vchiq_arm_log_level,
1596                                 "Failed to get user pages: %d\n", rc);
1597                 goto out;
1598         }
1599
1600         while (offset < end_offset) {
1601
1602                 int page_offset = offset % PAGE_SIZE;
1603                 page_idx = offset / PAGE_SIZE;
1604
1605                 if (page_idx != prev_idx) {
1606
1607                         if (page != NULL)
1608                                 kunmap(page);
1609                         page = pages[page_idx];
1610                         kmapped_virt_ptr = kmap(page);
1611
1612                         prev_idx = page_idx;
1613                 }
1614
1615                 if (vchiq_arm_log_level >= VCHIQ_LOG_TRACE)
1616                         vchiq_log_dump_mem("ph",
1617                                 (u32)(unsigned long)&kmapped_virt_ptr[
1618                                         page_offset],
1619                                 &kmapped_virt_ptr[page_offset], 16);
1620
1621                 offset += 16;
1622         }
1623
1624 out:
1625         if (page != NULL)
1626                 kunmap(page);
1627
1628         for (page_idx = 0; page_idx < num_pages; page_idx++)
1629                 put_page(pages[page_idx]);
1630
1631         kfree(pages);
1632 }
1633
1634 /****************************************************************************
1635 *
1636 *   vchiq_read
1637 *
1638 ***************************************************************************/
1639
1640 static ssize_t
1641 vchiq_read(struct file *file, char __user *buf,
1642         size_t count, loff_t *ppos)
1643 {
1644         DUMP_CONTEXT_T context;
1645         context.buf = buf;
1646         context.actual = 0;
1647         context.space = count;
1648         context.offset = *ppos;
1649
1650         vchiq_dump_state(&context, &g_state);
1651
1652         *ppos += context.actual;
1653
1654         return context.actual;
1655 }
1656
1657 VCHIQ_STATE_T *
1658 vchiq_get_state(void)
1659 {
1660
1661         if (g_state.remote == NULL)
1662                 printk(KERN_ERR "%s: g_state.remote == NULL\n", __func__);
1663         else if (g_state.remote->initialised != 1)
1664                 printk(KERN_NOTICE "%s: g_state.remote->initialised != 1 (%d)\n",
1665                         __func__, g_state.remote->initialised);
1666
1667         return ((g_state.remote != NULL) &&
1668                 (g_state.remote->initialised == 1)) ? &g_state : NULL;
1669 }
1670
1671 static const struct file_operations
1672 vchiq_fops = {
1673         .owner = THIS_MODULE,
1674         .unlocked_ioctl = vchiq_ioctl,
1675         .open = vchiq_open,
1676         .release = vchiq_release,
1677         .read = vchiq_read
1678 };
1679
1680 /*
1681  * Autosuspend related functionality
1682  */
1683
1684 int
1685 vchiq_videocore_wanted(VCHIQ_STATE_T *state)
1686 {
1687         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1688         if (!arm_state)
1689                 /* autosuspend not supported - always return wanted */
1690                 return 1;
1691         else if (arm_state->blocked_count)
1692                 return 1;
1693         else if (!arm_state->videocore_use_count)
1694                 /* usage count zero - check for override unless we're forcing */
1695                 if (arm_state->resume_blocked)
1696                         return 0;
1697                 else
1698                         return vchiq_platform_videocore_wanted(state);
1699         else
1700                 /* non-zero usage count - videocore still required */
1701                 return 1;
1702 }
1703
1704 static VCHIQ_STATUS_T
1705 vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,
1706         VCHIQ_HEADER_T *header,
1707         VCHIQ_SERVICE_HANDLE_T service_user,
1708         void *bulk_user)
1709 {
1710         vchiq_log_error(vchiq_susp_log_level,
1711                 "%s callback reason %d", __func__, reason);
1712         return 0;
1713 }
1714
1715 static int
1716 vchiq_keepalive_thread_func(void *v)
1717 {
1718         VCHIQ_STATE_T *state = (VCHIQ_STATE_T *) v;
1719         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1720
1721         VCHIQ_STATUS_T status;
1722         VCHIQ_INSTANCE_T instance;
1723         VCHIQ_SERVICE_HANDLE_T ka_handle;
1724
1725         VCHIQ_SERVICE_PARAMS_T params = {
1726                 .fourcc      = VCHIQ_MAKE_FOURCC('K', 'E', 'E', 'P'),
1727                 .callback    = vchiq_keepalive_vchiq_callback,
1728                 .version     = KEEPALIVE_VER,
1729                 .version_min = KEEPALIVE_VER_MIN
1730         };
1731
1732         status = vchiq_initialise(&instance);
1733         if (status != VCHIQ_SUCCESS) {
1734                 vchiq_log_error(vchiq_susp_log_level,
1735                         "%s vchiq_initialise failed %d", __func__, status);
1736                 goto exit;
1737         }
1738
1739         status = vchiq_connect(instance);
1740         if (status != VCHIQ_SUCCESS) {
1741                 vchiq_log_error(vchiq_susp_log_level,
1742                         "%s vchiq_connect failed %d", __func__, status);
1743                 goto shutdown;
1744         }
1745
1746         status = vchiq_add_service(instance, &params, &ka_handle);
1747         if (status != VCHIQ_SUCCESS) {
1748                 vchiq_log_error(vchiq_susp_log_level,
1749                         "%s vchiq_open_service failed %d", __func__, status);
1750                 goto shutdown;
1751         }
1752
1753         while (1) {
1754                 long rc = 0, uc = 0;
1755                 if (wait_for_completion_interruptible(&arm_state->ka_evt)
1756                                 != 0) {
1757                         vchiq_log_error(vchiq_susp_log_level,
1758                                 "%s interrupted", __func__);
1759                         flush_signals(current);
1760                         continue;
1761                 }
1762
1763                 /* read and clear counters.  Do release_count then use_count to
1764                  * prevent getting more releases than uses */
1765                 rc = atomic_xchg(&arm_state->ka_release_count, 0);
1766                 uc = atomic_xchg(&arm_state->ka_use_count, 0);
1767
1768                 /* Call use/release service the requisite number of times.
1769                  * Process use before release so use counts don't go negative */
1770                 while (uc--) {
1771                         atomic_inc(&arm_state->ka_use_ack_count);
1772                         status = vchiq_use_service(ka_handle);
1773                         if (status != VCHIQ_SUCCESS) {
1774                                 vchiq_log_error(vchiq_susp_log_level,
1775                                         "%s vchiq_use_service error %d",
1776                                         __func__, status);
1777                         }
1778                 }
1779                 while (rc--) {
1780                         status = vchiq_release_service(ka_handle);
1781                         if (status != VCHIQ_SUCCESS) {
1782                                 vchiq_log_error(vchiq_susp_log_level,
1783                                         "%s vchiq_release_service error %d",
1784                                         __func__, status);
1785                         }
1786                 }
1787         }
1788
1789 shutdown:
1790         vchiq_shutdown(instance);
1791 exit:
1792         return 0;
1793 }
1794
1795
1796
1797 VCHIQ_STATUS_T
1798 vchiq_arm_init_state(VCHIQ_STATE_T *state, VCHIQ_ARM_STATE_T *arm_state)
1799 {
1800         if (arm_state) {
1801                 rwlock_init(&arm_state->susp_res_lock);
1802
1803                 init_completion(&arm_state->ka_evt);
1804                 atomic_set(&arm_state->ka_use_count, 0);
1805                 atomic_set(&arm_state->ka_use_ack_count, 0);
1806                 atomic_set(&arm_state->ka_release_count, 0);
1807
1808                 init_completion(&arm_state->vc_suspend_complete);
1809
1810                 init_completion(&arm_state->vc_resume_complete);
1811                 /* Initialise to 'done' state.  We only want to block on resume
1812                  * completion while videocore is suspended. */
1813                 set_resume_state(arm_state, VC_RESUME_RESUMED);
1814
1815                 init_completion(&arm_state->resume_blocker);
1816                 /* Initialise to 'done' state.  We only want to block on this
1817                  * completion while resume is blocked */
1818                 complete_all(&arm_state->resume_blocker);
1819
1820                 init_completion(&arm_state->blocked_blocker);
1821                 /* Initialise to 'done' state.  We only want to block on this
1822                  * completion while things are waiting on the resume blocker */
1823                 complete_all(&arm_state->blocked_blocker);
1824
1825                 arm_state->suspend_timer_timeout = SUSPEND_TIMER_TIMEOUT_MS;
1826                 arm_state->suspend_timer_running = 0;
1827                 setup_timer(&arm_state->suspend_timer, suspend_timer_callback,
1828                             (unsigned long)(state));
1829
1830                 arm_state->first_connect = 0;
1831
1832         }
1833         return VCHIQ_SUCCESS;
1834 }
1835
1836 /*
1837 ** Functions to modify the state variables;
1838 **      set_suspend_state
1839 **      set_resume_state
1840 **
1841 ** There are more state variables than we might like, so ensure they remain in
1842 ** step.  Suspend and resume state are maintained separately, since most of
1843 ** these state machines can operate independently.  However, there are a few
1844 ** states where state transitions in one state machine cause a reset to the
1845 ** other state machine.  In addition, there are some completion events which
1846 ** need to occur on state machine reset and end-state(s), so these are also
1847 ** dealt with in these functions.
1848 **
1849 ** In all states we set the state variable according to the input, but in some
1850 ** cases we perform additional steps outlined below;
1851 **
1852 ** VC_SUSPEND_IDLE - Initialise the suspend completion at the same time.
1853 **                      The suspend completion is completed after any suspend
1854 **                      attempt.  When we reset the state machine we also reset
1855 **                      the completion.  This reset occurs when videocore is
1856 **                      resumed, and also if we initiate suspend after a suspend
1857 **                      failure.
1858 **
1859 ** VC_SUSPEND_IN_PROGRESS - This state is considered the point of no return for
1860 **                      suspend - ie from this point on we must try to suspend
1861 **                      before resuming can occur.  We therefore also reset the
1862 **                      resume state machine to VC_RESUME_IDLE in this state.
1863 **
1864 ** VC_SUSPEND_SUSPENDED - Suspend has completed successfully. Also call
1865 **                      complete_all on the suspend completion to notify
1866 **                      anything waiting for suspend to happen.
1867 **
1868 ** VC_SUSPEND_REJECTED - Videocore rejected suspend. Videocore will also
1869 **                      initiate resume, so no need to alter resume state.
1870 **                      We call complete_all on the suspend completion to notify
1871 **                      of suspend rejection.
1872 **
1873 ** VC_SUSPEND_FAILED - We failed to initiate videocore suspend.  We notify the
1874 **                      suspend completion and reset the resume state machine.
1875 **
1876 ** VC_RESUME_IDLE - Initialise the resume completion at the same time.  The
1877 **                      resume completion is in it's 'done' state whenever
1878 **                      videcore is running.  Therefore, the VC_RESUME_IDLE
1879 **                      state implies that videocore is suspended.
1880 **                      Hence, any thread which needs to wait until videocore is
1881 **                      running can wait on this completion - it will only block
1882 **                      if videocore is suspended.
1883 **
1884 ** VC_RESUME_RESUMED - Resume has completed successfully.  Videocore is running.
1885 **                      Call complete_all on the resume completion to unblock
1886 **                      any threads waiting for resume.  Also reset the suspend
1887 **                      state machine to it's idle state.
1888 **
1889 ** VC_RESUME_FAILED - Currently unused - no mechanism to fail resume exists.
1890 */
1891
1892 void
1893 set_suspend_state(VCHIQ_ARM_STATE_T *arm_state,
1894         enum vc_suspend_status new_state)
1895 {
1896         /* set the state in all cases */
1897         arm_state->vc_suspend_state = new_state;
1898
1899         /* state specific additional actions */
1900         switch (new_state) {
1901         case VC_SUSPEND_FORCE_CANCELED:
1902                 complete_all(&arm_state->vc_suspend_complete);
1903                 break;
1904         case VC_SUSPEND_REJECTED:
1905                 complete_all(&arm_state->vc_suspend_complete);
1906                 break;
1907         case VC_SUSPEND_FAILED:
1908                 complete_all(&arm_state->vc_suspend_complete);
1909                 arm_state->vc_resume_state = VC_RESUME_RESUMED;
1910                 complete_all(&arm_state->vc_resume_complete);
1911                 break;
1912         case VC_SUSPEND_IDLE:
1913                 reinit_completion(&arm_state->vc_suspend_complete);
1914                 break;
1915         case VC_SUSPEND_REQUESTED:
1916                 break;
1917         case VC_SUSPEND_IN_PROGRESS:
1918                 set_resume_state(arm_state, VC_RESUME_IDLE);
1919                 break;
1920         case VC_SUSPEND_SUSPENDED:
1921                 complete_all(&arm_state->vc_suspend_complete);
1922                 break;
1923         default:
1924                 BUG();
1925                 break;
1926         }
1927 }
1928
1929 void
1930 set_resume_state(VCHIQ_ARM_STATE_T *arm_state,
1931         enum vc_resume_status new_state)
1932 {
1933         /* set the state in all cases */
1934         arm_state->vc_resume_state = new_state;
1935
1936         /* state specific additional actions */
1937         switch (new_state) {
1938         case VC_RESUME_FAILED:
1939                 break;
1940         case VC_RESUME_IDLE:
1941                 reinit_completion(&arm_state->vc_resume_complete);
1942                 break;
1943         case VC_RESUME_REQUESTED:
1944                 break;
1945         case VC_RESUME_IN_PROGRESS:
1946                 break;
1947         case VC_RESUME_RESUMED:
1948                 complete_all(&arm_state->vc_resume_complete);
1949                 set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1950                 break;
1951         default:
1952                 BUG();
1953                 break;
1954         }
1955 }
1956
1957
1958 /* should be called with the write lock held */
1959 inline void
1960 start_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1961 {
1962         del_timer(&arm_state->suspend_timer);
1963         arm_state->suspend_timer.expires = jiffies +
1964                 msecs_to_jiffies(arm_state->
1965                         suspend_timer_timeout);
1966         add_timer(&arm_state->suspend_timer);
1967         arm_state->suspend_timer_running = 1;
1968 }
1969
1970 /* should be called with the write lock held */
1971 static inline void
1972 stop_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1973 {
1974         if (arm_state->suspend_timer_running) {
1975                 del_timer(&arm_state->suspend_timer);
1976                 arm_state->suspend_timer_running = 0;
1977         }
1978 }
1979
1980 static inline int
1981 need_resume(VCHIQ_STATE_T *state)
1982 {
1983         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1984         return (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) &&
1985                         (arm_state->vc_resume_state < VC_RESUME_REQUESTED) &&
1986                         vchiq_videocore_wanted(state);
1987 }
1988
1989 static int
1990 block_resume(VCHIQ_ARM_STATE_T *arm_state)
1991 {
1992         int status = VCHIQ_SUCCESS;
1993         const unsigned long timeout_val =
1994                                 msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS);
1995         int resume_count = 0;
1996
1997         /* Allow any threads which were blocked by the last force suspend to
1998          * complete if they haven't already.  Only give this one shot; if
1999          * blocked_count is incremented after blocked_blocker is completed
2000          * (which only happens when blocked_count hits 0) then those threads
2001          * will have to wait until next time around */
2002         if (arm_state->blocked_count) {
2003                 reinit_completion(&arm_state->blocked_blocker);
2004                 write_unlock_bh(&arm_state->susp_res_lock);
2005                 vchiq_log_info(vchiq_susp_log_level, "%s wait for previously "
2006                         "blocked clients", __func__);
2007                 if (wait_for_completion_interruptible_timeout(
2008                                 &arm_state->blocked_blocker, timeout_val)
2009                                         <= 0) {
2010                         vchiq_log_error(vchiq_susp_log_level, "%s wait for "
2011                                 "previously blocked clients failed", __func__);
2012                         status = VCHIQ_ERROR;
2013                         write_lock_bh(&arm_state->susp_res_lock);
2014                         goto out;
2015                 }
2016                 vchiq_log_info(vchiq_susp_log_level, "%s previously blocked "
2017                         "clients resumed", __func__);
2018                 write_lock_bh(&arm_state->susp_res_lock);
2019         }
2020
2021         /* We need to wait for resume to complete if it's in process */
2022         while (arm_state->vc_resume_state != VC_RESUME_RESUMED &&
2023                         arm_state->vc_resume_state > VC_RESUME_IDLE) {
2024                 if (resume_count > 1) {
2025                         status = VCHIQ_ERROR;
2026                         vchiq_log_error(vchiq_susp_log_level, "%s waited too "
2027                                 "many times for resume", __func__);
2028                         goto out;
2029                 }
2030                 write_unlock_bh(&arm_state->susp_res_lock);
2031                 vchiq_log_info(vchiq_susp_log_level, "%s wait for resume",
2032                         __func__);
2033                 if (wait_for_completion_interruptible_timeout(
2034                                 &arm_state->vc_resume_complete, timeout_val)
2035                                         <= 0) {
2036                         vchiq_log_error(vchiq_susp_log_level, "%s wait for "
2037                                 "resume failed (%s)", __func__,
2038                                 resume_state_names[arm_state->vc_resume_state +
2039                                                         VC_RESUME_NUM_OFFSET]);
2040                         status = VCHIQ_ERROR;
2041                         write_lock_bh(&arm_state->susp_res_lock);
2042                         goto out;
2043                 }
2044                 vchiq_log_info(vchiq_susp_log_level, "%s resumed", __func__);
2045                 write_lock_bh(&arm_state->susp_res_lock);
2046                 resume_count++;
2047         }
2048         reinit_completion(&arm_state->resume_blocker);
2049         arm_state->resume_blocked = 1;
2050
2051 out:
2052         return status;
2053 }
2054
2055 static inline void
2056 unblock_resume(VCHIQ_ARM_STATE_T *arm_state)
2057 {
2058         complete_all(&arm_state->resume_blocker);
2059         arm_state->resume_blocked = 0;
2060 }
2061
2062 /* Initiate suspend via slot handler. Should be called with the write lock
2063  * held */
2064 VCHIQ_STATUS_T
2065 vchiq_arm_vcsuspend(VCHIQ_STATE_T *state)
2066 {
2067         VCHIQ_STATUS_T status = VCHIQ_ERROR;
2068         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2069
2070         if (!arm_state)
2071                 goto out;
2072
2073         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2074         status = VCHIQ_SUCCESS;
2075
2076
2077         switch (arm_state->vc_suspend_state) {
2078         case VC_SUSPEND_REQUESTED:
2079                 vchiq_log_info(vchiq_susp_log_level, "%s: suspend already "
2080                         "requested", __func__);
2081                 break;
2082         case VC_SUSPEND_IN_PROGRESS:
2083                 vchiq_log_info(vchiq_susp_log_level, "%s: suspend already in "
2084                         "progress", __func__);
2085                 break;
2086
2087         default:
2088                 /* We don't expect to be in other states, so log but continue
2089                  * anyway */
2090                 vchiq_log_error(vchiq_susp_log_level,
2091                         "%s unexpected suspend state %s", __func__,
2092                         suspend_state_names[arm_state->vc_suspend_state +
2093                                                 VC_SUSPEND_NUM_OFFSET]);
2094                 /* fall through */
2095         case VC_SUSPEND_REJECTED:
2096         case VC_SUSPEND_FAILED:
2097                 /* Ensure any idle state actions have been run */
2098                 set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2099                 /* fall through */
2100         case VC_SUSPEND_IDLE:
2101                 vchiq_log_info(vchiq_susp_log_level,
2102                         "%s: suspending", __func__);
2103                 set_suspend_state(arm_state, VC_SUSPEND_REQUESTED);
2104                 /* kick the slot handler thread to initiate suspend */
2105                 request_poll(state, NULL, 0);
2106                 break;
2107         }
2108
2109 out:
2110         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2111         return status;
2112 }
2113
2114 void
2115 vchiq_platform_check_suspend(VCHIQ_STATE_T *state)
2116 {
2117         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2118         int susp = 0;
2119
2120         if (!arm_state)
2121                 goto out;
2122
2123         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2124
2125         write_lock_bh(&arm_state->susp_res_lock);
2126         if (arm_state->vc_suspend_state == VC_SUSPEND_REQUESTED &&
2127                         arm_state->vc_resume_state == VC_RESUME_RESUMED) {
2128                 set_suspend_state(arm_state, VC_SUSPEND_IN_PROGRESS);
2129                 susp = 1;
2130         }
2131         write_unlock_bh(&arm_state->susp_res_lock);
2132
2133         if (susp)
2134                 vchiq_platform_suspend(state);
2135
2136 out:
2137         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2138         return;
2139 }
2140
2141
2142 static void
2143 output_timeout_error(VCHIQ_STATE_T *state)
2144 {
2145         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2146         char err[50] = "";
2147         int vc_use_count = arm_state->videocore_use_count;
2148         int active_services = state->unused_service;
2149         int i;
2150
2151         if (!arm_state->videocore_use_count) {
2152                 snprintf(err, sizeof(err), " Videocore usecount is 0");
2153                 goto output_msg;
2154         }
2155         for (i = 0; i < active_services; i++) {
2156                 VCHIQ_SERVICE_T *service_ptr = state->services[i];
2157                 if (service_ptr && service_ptr->service_use_count &&
2158                         (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE)) {
2159                         snprintf(err, sizeof(err), " %c%c%c%c(%d) service has "
2160                                 "use count %d%s", VCHIQ_FOURCC_AS_4CHARS(
2161                                         service_ptr->base.fourcc),
2162                                  service_ptr->client_id,
2163                                  service_ptr->service_use_count,
2164                                  service_ptr->service_use_count ==
2165                                          vc_use_count ? "" : " (+ more)");
2166                         break;
2167                 }
2168         }
2169
2170 output_msg:
2171         vchiq_log_error(vchiq_susp_log_level,
2172                 "timed out waiting for vc suspend (%d).%s",
2173                  arm_state->autosuspend_override, err);
2174
2175 }
2176
2177 /* Try to get videocore into suspended state, regardless of autosuspend state.
2178 ** We don't actually force suspend, since videocore may get into a bad state
2179 ** if we force suspend at a bad time.  Instead, we wait for autosuspend to
2180 ** determine a good point to suspend.  If this doesn't happen within 100ms we
2181 ** report failure.
2182 **
2183 ** Returns VCHIQ_SUCCESS if videocore suspended successfully, VCHIQ_RETRY if
2184 ** videocore failed to suspend in time or VCHIQ_ERROR if interrupted.
2185 */
2186 VCHIQ_STATUS_T
2187 vchiq_arm_force_suspend(VCHIQ_STATE_T *state)
2188 {
2189         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2190         VCHIQ_STATUS_T status = VCHIQ_ERROR;
2191         long rc = 0;
2192         int repeat = -1;
2193
2194         if (!arm_state)
2195                 goto out;
2196
2197         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2198
2199         write_lock_bh(&arm_state->susp_res_lock);
2200
2201         status = block_resume(arm_state);
2202         if (status != VCHIQ_SUCCESS)
2203                 goto unlock;
2204         if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2205                 /* Already suspended - just block resume and exit */
2206                 vchiq_log_info(vchiq_susp_log_level, "%s already suspended",
2207                         __func__);
2208                 status = VCHIQ_SUCCESS;
2209                 goto unlock;
2210         } else if (arm_state->vc_suspend_state <= VC_SUSPEND_IDLE) {
2211                 /* initiate suspend immediately in the case that we're waiting
2212                  * for the timeout */
2213                 stop_suspend_timer(arm_state);
2214                 if (!vchiq_videocore_wanted(state)) {
2215                         vchiq_log_info(vchiq_susp_log_level, "%s videocore "
2216                                 "idle, initiating suspend", __func__);
2217                         status = vchiq_arm_vcsuspend(state);
2218                 } else if (arm_state->autosuspend_override <
2219                                                 FORCE_SUSPEND_FAIL_MAX) {
2220                         vchiq_log_info(vchiq_susp_log_level, "%s letting "
2221                                 "videocore go idle", __func__);
2222                         status = VCHIQ_SUCCESS;
2223                 } else {
2224                         vchiq_log_warning(vchiq_susp_log_level, "%s failed too "
2225                                 "many times - attempting suspend", __func__);
2226                         status = vchiq_arm_vcsuspend(state);
2227                 }
2228         } else {
2229                 vchiq_log_info(vchiq_susp_log_level, "%s videocore suspend "
2230                         "in progress - wait for completion", __func__);
2231                 status = VCHIQ_SUCCESS;
2232         }
2233
2234         /* Wait for suspend to happen due to system idle (not forced..) */
2235         if (status != VCHIQ_SUCCESS)
2236                 goto unblock_resume;
2237
2238         do {
2239                 write_unlock_bh(&arm_state->susp_res_lock);
2240
2241                 rc = wait_for_completion_interruptible_timeout(
2242                                 &arm_state->vc_suspend_complete,
2243                                 msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS));
2244
2245                 write_lock_bh(&arm_state->susp_res_lock);
2246                 if (rc < 0) {
2247                         vchiq_log_warning(vchiq_susp_log_level, "%s "
2248                                 "interrupted waiting for suspend", __func__);
2249                         status = VCHIQ_ERROR;
2250                         goto unblock_resume;
2251                 } else if (rc == 0) {
2252                         if (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) {
2253                                 /* Repeat timeout once if in progress */
2254                                 if (repeat < 0) {
2255                                         repeat = 1;
2256                                         continue;
2257                                 }
2258                         }
2259                         arm_state->autosuspend_override++;
2260                         output_timeout_error(state);
2261
2262                         status = VCHIQ_RETRY;
2263                         goto unblock_resume;
2264                 }
2265         } while (0 < (repeat--));
2266
2267         /* Check and report state in case we need to abort ARM suspend */
2268         if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED) {
2269                 status = VCHIQ_RETRY;
2270                 vchiq_log_error(vchiq_susp_log_level,
2271                         "%s videocore suspend failed (state %s)", __func__,
2272                         suspend_state_names[arm_state->vc_suspend_state +
2273                                                 VC_SUSPEND_NUM_OFFSET]);
2274                 /* Reset the state only if it's still in an error state.
2275                  * Something could have already initiated another suspend. */
2276                 if (arm_state->vc_suspend_state < VC_SUSPEND_IDLE)
2277                         set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2278
2279                 goto unblock_resume;
2280         }
2281
2282         /* successfully suspended - unlock and exit */
2283         goto unlock;
2284
2285 unblock_resume:
2286         /* all error states need to unblock resume before exit */
2287         unblock_resume(arm_state);
2288
2289 unlock:
2290         write_unlock_bh(&arm_state->susp_res_lock);
2291
2292 out:
2293         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2294         return status;
2295 }
2296
2297 void
2298 vchiq_check_suspend(VCHIQ_STATE_T *state)
2299 {
2300         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2301
2302         if (!arm_state)
2303                 goto out;
2304
2305         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2306
2307         write_lock_bh(&arm_state->susp_res_lock);
2308         if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED &&
2309                         arm_state->first_connect &&
2310                         !vchiq_videocore_wanted(state)) {
2311                 vchiq_arm_vcsuspend(state);
2312         }
2313         write_unlock_bh(&arm_state->susp_res_lock);
2314
2315 out:
2316         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2317         return;
2318 }
2319
2320
2321 int
2322 vchiq_arm_allow_resume(VCHIQ_STATE_T *state)
2323 {
2324         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2325         int resume = 0;
2326         int ret = -1;
2327
2328         if (!arm_state)
2329                 goto out;
2330
2331         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2332
2333         write_lock_bh(&arm_state->susp_res_lock);
2334         unblock_resume(arm_state);
2335         resume = vchiq_check_resume(state);
2336         write_unlock_bh(&arm_state->susp_res_lock);
2337
2338         if (resume) {
2339                 if (wait_for_completion_interruptible(
2340                         &arm_state->vc_resume_complete) < 0) {
2341                         vchiq_log_error(vchiq_susp_log_level,
2342                                 "%s interrupted", __func__);
2343                         /* failed, cannot accurately derive suspend
2344                          * state, so exit early. */
2345                         goto out;
2346                 }
2347         }
2348
2349         read_lock_bh(&arm_state->susp_res_lock);
2350         if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2351                 vchiq_log_info(vchiq_susp_log_level,
2352                                 "%s: Videocore remains suspended", __func__);
2353         } else {
2354                 vchiq_log_info(vchiq_susp_log_level,
2355                                 "%s: Videocore resumed", __func__);
2356                 ret = 0;
2357         }
2358         read_unlock_bh(&arm_state->susp_res_lock);
2359 out:
2360         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2361         return ret;
2362 }
2363
2364 /* This function should be called with the write lock held */
2365 int
2366 vchiq_check_resume(VCHIQ_STATE_T *state)
2367 {
2368         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2369         int resume = 0;
2370
2371         if (!arm_state)
2372                 goto out;
2373
2374         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2375
2376         if (need_resume(state)) {
2377                 set_resume_state(arm_state, VC_RESUME_REQUESTED);
2378                 request_poll(state, NULL, 0);
2379                 resume = 1;
2380         }
2381
2382 out:
2383         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2384         return resume;
2385 }
2386
2387 VCHIQ_STATUS_T
2388 vchiq_use_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service,
2389                 enum USE_TYPE_E use_type)
2390 {
2391         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2392         VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2393         char entity[16];
2394         int *entity_uc;
2395         int local_uc, local_entity_uc;
2396
2397         if (!arm_state)
2398                 goto out;
2399
2400         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2401
2402         if (use_type == USE_TYPE_VCHIQ) {
2403                 sprintf(entity, "VCHIQ:   ");
2404                 entity_uc = &arm_state->peer_use_count;
2405         } else if (service) {
2406                 sprintf(entity, "%c%c%c%c:%03d",
2407                         VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2408                         service->client_id);
2409                 entity_uc = &service->service_use_count;
2410         } else {
2411                 vchiq_log_error(vchiq_susp_log_level, "%s null service "
2412                                 "ptr", __func__);
2413                 ret = VCHIQ_ERROR;
2414                 goto out;
2415         }
2416
2417         write_lock_bh(&arm_state->susp_res_lock);
2418         while (arm_state->resume_blocked) {
2419                 /* If we call 'use' while force suspend is waiting for suspend,
2420                  * then we're about to block the thread which the force is
2421                  * waiting to complete, so we're bound to just time out. In this
2422                  * case, set the suspend state such that the wait will be
2423                  * canceled, so we can complete as quickly as possible. */
2424                 if (arm_state->resume_blocked && arm_state->vc_suspend_state ==
2425                                 VC_SUSPEND_IDLE) {
2426                         set_suspend_state(arm_state, VC_SUSPEND_FORCE_CANCELED);
2427                         break;
2428                 }
2429                 /* If suspend is already in progress then we need to block */
2430                 if (!try_wait_for_completion(&arm_state->resume_blocker)) {
2431                         /* Indicate that there are threads waiting on the resume
2432                          * blocker.  These need to be allowed to complete before
2433                          * a _second_ call to force suspend can complete,
2434                          * otherwise low priority threads might never actually
2435                          * continue */
2436                         arm_state->blocked_count++;
2437                         write_unlock_bh(&arm_state->susp_res_lock);
2438                         vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2439                                 "blocked - waiting...", __func__, entity);
2440                         if (wait_for_completion_killable(
2441                                         &arm_state->resume_blocker) != 0) {
2442                                 vchiq_log_error(vchiq_susp_log_level, "%s %s "
2443                                         "wait for resume blocker interrupted",
2444                                         __func__, entity);
2445                                 ret = VCHIQ_ERROR;
2446                                 write_lock_bh(&arm_state->susp_res_lock);
2447                                 arm_state->blocked_count--;
2448                                 write_unlock_bh(&arm_state->susp_res_lock);
2449                                 goto out;
2450                         }
2451                         vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2452                                 "unblocked", __func__, entity);
2453                         write_lock_bh(&arm_state->susp_res_lock);
2454                         if (--arm_state->blocked_count == 0)
2455                                 complete_all(&arm_state->blocked_blocker);
2456                 }
2457         }
2458
2459         stop_suspend_timer(arm_state);
2460
2461         local_uc = ++arm_state->videocore_use_count;
2462         local_entity_uc = ++(*entity_uc);
2463
2464         /* If there's a pending request which hasn't yet been serviced then
2465          * just clear it.  If we're past VC_SUSPEND_REQUESTED state then
2466          * vc_resume_complete will block until we either resume or fail to
2467          * suspend */
2468         if (arm_state->vc_suspend_state <= VC_SUSPEND_REQUESTED)
2469                 set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2470
2471         if ((use_type != USE_TYPE_SERVICE_NO_RESUME) && need_resume(state)) {
2472                 set_resume_state(arm_state, VC_RESUME_REQUESTED);
2473                 vchiq_log_info(vchiq_susp_log_level,
2474                         "%s %s count %d, state count %d",
2475                         __func__, entity, local_entity_uc, local_uc);
2476                 request_poll(state, NULL, 0);
2477         } else
2478                 vchiq_log_trace(vchiq_susp_log_level,
2479                         "%s %s count %d, state count %d",
2480                         __func__, entity, *entity_uc, local_uc);
2481
2482
2483         write_unlock_bh(&arm_state->susp_res_lock);
2484
2485         /* Completion is in a done state when we're not suspended, so this won't
2486          * block for the non-suspended case. */
2487         if (!try_wait_for_completion(&arm_state->vc_resume_complete)) {
2488                 vchiq_log_info(vchiq_susp_log_level, "%s %s wait for resume",
2489                         __func__, entity);
2490                 if (wait_for_completion_killable(
2491                                 &arm_state->vc_resume_complete) != 0) {
2492                         vchiq_log_error(vchiq_susp_log_level, "%s %s wait for "
2493                                 "resume interrupted", __func__, entity);
2494                         ret = VCHIQ_ERROR;
2495                         goto out;
2496                 }
2497                 vchiq_log_info(vchiq_susp_log_level, "%s %s resumed", __func__,
2498                         entity);
2499         }
2500
2501         if (ret == VCHIQ_SUCCESS) {
2502                 VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
2503                 long ack_cnt = atomic_xchg(&arm_state->ka_use_ack_count, 0);
2504                 while (ack_cnt && (status == VCHIQ_SUCCESS)) {
2505                         /* Send the use notify to videocore */
2506                         status = vchiq_send_remote_use_active(state);
2507                         if (status == VCHIQ_SUCCESS)
2508                                 ack_cnt--;
2509                         else
2510                                 atomic_add(ack_cnt,
2511                                         &arm_state->ka_use_ack_count);
2512                 }
2513         }
2514
2515 out:
2516         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2517         return ret;
2518 }
2519
2520 VCHIQ_STATUS_T
2521 vchiq_release_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service)
2522 {
2523         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2524         VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2525         char entity[16];
2526         int *entity_uc;
2527         int local_uc, local_entity_uc;
2528
2529         if (!arm_state)
2530                 goto out;
2531
2532         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2533
2534         if (service) {
2535                 sprintf(entity, "%c%c%c%c:%03d",
2536                         VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2537                         service->client_id);
2538                 entity_uc = &service->service_use_count;
2539         } else {
2540                 sprintf(entity, "PEER:   ");
2541                 entity_uc = &arm_state->peer_use_count;
2542         }
2543
2544         write_lock_bh(&arm_state->susp_res_lock);
2545         if (!arm_state->videocore_use_count || !(*entity_uc)) {
2546                 /* Don't use BUG_ON - don't allow user thread to crash kernel */
2547                 WARN_ON(!arm_state->videocore_use_count);
2548                 WARN_ON(!(*entity_uc));
2549                 ret = VCHIQ_ERROR;
2550                 goto unlock;
2551         }
2552         local_uc = --arm_state->videocore_use_count;
2553         local_entity_uc = --(*entity_uc);
2554
2555         if (!vchiq_videocore_wanted(state)) {
2556                 if (vchiq_platform_use_suspend_timer() &&
2557                                 !arm_state->resume_blocked) {
2558                         /* Only use the timer if we're not trying to force
2559                          * suspend (=> resume_blocked) */
2560                         start_suspend_timer(arm_state);
2561                 } else {
2562                         vchiq_log_info(vchiq_susp_log_level,
2563                                 "%s %s count %d, state count %d - suspending",
2564                                 __func__, entity, *entity_uc,
2565                                 arm_state->videocore_use_count);
2566                         vchiq_arm_vcsuspend(state);
2567                 }
2568         } else
2569                 vchiq_log_trace(vchiq_susp_log_level,
2570                         "%s %s count %d, state count %d",
2571                         __func__, entity, *entity_uc,
2572                         arm_state->videocore_use_count);
2573
2574 unlock:
2575         write_unlock_bh(&arm_state->susp_res_lock);
2576
2577 out:
2578         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2579         return ret;
2580 }
2581
2582 void
2583 vchiq_on_remote_use(VCHIQ_STATE_T *state)
2584 {
2585         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2586         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2587         atomic_inc(&arm_state->ka_use_count);
2588         complete(&arm_state->ka_evt);
2589 }
2590
2591 void
2592 vchiq_on_remote_release(VCHIQ_STATE_T *state)
2593 {
2594         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2595         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2596         atomic_inc(&arm_state->ka_release_count);
2597         complete(&arm_state->ka_evt);
2598 }
2599
2600 VCHIQ_STATUS_T
2601 vchiq_use_service_internal(VCHIQ_SERVICE_T *service)
2602 {
2603         return vchiq_use_internal(service->state, service, USE_TYPE_SERVICE);
2604 }
2605
2606 VCHIQ_STATUS_T
2607 vchiq_release_service_internal(VCHIQ_SERVICE_T *service)
2608 {
2609         return vchiq_release_internal(service->state, service);
2610 }
2611
2612 VCHIQ_DEBUGFS_NODE_T *
2613 vchiq_instance_get_debugfs_node(VCHIQ_INSTANCE_T instance)
2614 {
2615         return &instance->debugfs_node;
2616 }
2617
2618 int
2619 vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)
2620 {
2621         VCHIQ_SERVICE_T *service;
2622         int use_count = 0, i;
2623         i = 0;
2624         while ((service = next_service_by_instance(instance->state,
2625                 instance, &i)) != NULL) {
2626                 use_count += service->service_use_count;
2627                 unlock_service(service);
2628         }
2629         return use_count;
2630 }
2631
2632 int
2633 vchiq_instance_get_pid(VCHIQ_INSTANCE_T instance)
2634 {
2635         return instance->pid;
2636 }
2637
2638 int
2639 vchiq_instance_get_trace(VCHIQ_INSTANCE_T instance)
2640 {
2641         return instance->trace;
2642 }
2643
2644 void
2645 vchiq_instance_set_trace(VCHIQ_INSTANCE_T instance, int trace)
2646 {
2647         VCHIQ_SERVICE_T *service;
2648         int i;
2649         i = 0;
2650         while ((service = next_service_by_instance(instance->state,
2651                 instance, &i)) != NULL) {
2652                 service->trace = trace;
2653                 unlock_service(service);
2654         }
2655         instance->trace = (trace != 0);
2656 }
2657
2658 static void suspend_timer_callback(unsigned long context)
2659 {
2660         VCHIQ_STATE_T *state = (VCHIQ_STATE_T *)context;
2661         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2662         if (!arm_state)
2663                 goto out;
2664         vchiq_log_info(vchiq_susp_log_level,
2665                 "%s - suspend timer expired - check suspend", __func__);
2666         vchiq_check_suspend(state);
2667 out:
2668         return;
2669 }
2670
2671 VCHIQ_STATUS_T
2672 vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)
2673 {
2674         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2675         VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2676         if (service) {
2677                 ret = vchiq_use_internal(service->state, service,
2678                                 USE_TYPE_SERVICE_NO_RESUME);
2679                 unlock_service(service);
2680         }
2681         return ret;
2682 }
2683
2684 VCHIQ_STATUS_T
2685 vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)
2686 {
2687         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2688         VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2689         if (service) {
2690                 ret = vchiq_use_internal(service->state, service,
2691                                 USE_TYPE_SERVICE);
2692                 unlock_service(service);
2693         }
2694         return ret;
2695 }
2696
2697 VCHIQ_STATUS_T
2698 vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)
2699 {
2700         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2701         VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2702         if (service) {
2703                 ret = vchiq_release_internal(service->state, service);
2704                 unlock_service(service);
2705         }
2706         return ret;
2707 }
2708
2709 void
2710 vchiq_dump_service_use_state(VCHIQ_STATE_T *state)
2711 {
2712         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2713         int i, j = 0;
2714         /* Only dump 64 services */
2715         static const int local_max_services = 64;
2716         /* If there's more than 64 services, only dump ones with
2717          * non-zero counts */
2718         int only_nonzero = 0;
2719         static const char *nz = "<-- preventing suspend";
2720
2721         enum vc_suspend_status vc_suspend_state;
2722         enum vc_resume_status  vc_resume_state;
2723         int peer_count;
2724         int vc_use_count;
2725         int active_services;
2726         struct service_data_struct {
2727                 int fourcc;
2728                 int clientid;
2729                 int use_count;
2730         } service_data[local_max_services];
2731
2732         if (!arm_state)
2733                 return;
2734
2735         read_lock_bh(&arm_state->susp_res_lock);
2736         vc_suspend_state = arm_state->vc_suspend_state;
2737         vc_resume_state  = arm_state->vc_resume_state;
2738         peer_count = arm_state->peer_use_count;
2739         vc_use_count = arm_state->videocore_use_count;
2740         active_services = state->unused_service;
2741         if (active_services > local_max_services)
2742                 only_nonzero = 1;
2743
2744         for (i = 0; (i < active_services) && (j < local_max_services); i++) {
2745                 VCHIQ_SERVICE_T *service_ptr = state->services[i];
2746                 if (!service_ptr)
2747                         continue;
2748
2749                 if (only_nonzero && !service_ptr->service_use_count)
2750                         continue;
2751
2752                 if (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE) {
2753                         service_data[j].fourcc = service_ptr->base.fourcc;
2754                         service_data[j].clientid = service_ptr->client_id;
2755                         service_data[j++].use_count = service_ptr->
2756                                                         service_use_count;
2757                 }
2758         }
2759
2760         read_unlock_bh(&arm_state->susp_res_lock);
2761
2762         vchiq_log_warning(vchiq_susp_log_level,
2763                 "-- Videcore suspend state: %s --",
2764                 suspend_state_names[vc_suspend_state + VC_SUSPEND_NUM_OFFSET]);
2765         vchiq_log_warning(vchiq_susp_log_level,
2766                 "-- Videcore resume state: %s --",
2767                 resume_state_names[vc_resume_state + VC_RESUME_NUM_OFFSET]);
2768
2769         if (only_nonzero)
2770                 vchiq_log_warning(vchiq_susp_log_level, "Too many active "
2771                         "services (%d).  Only dumping up to first %d services "
2772                         "with non-zero use-count", active_services,
2773                         local_max_services);
2774
2775         for (i = 0; i < j; i++) {
2776                 vchiq_log_warning(vchiq_susp_log_level,
2777                         "----- %c%c%c%c:%d service count %d %s",
2778                         VCHIQ_FOURCC_AS_4CHARS(service_data[i].fourcc),
2779                         service_data[i].clientid,
2780                         service_data[i].use_count,
2781                         service_data[i].use_count ? nz : "");
2782         }
2783         vchiq_log_warning(vchiq_susp_log_level,
2784                 "----- VCHIQ use count count %d", peer_count);
2785         vchiq_log_warning(vchiq_susp_log_level,
2786                 "--- Overall vchiq instance use count %d", vc_use_count);
2787
2788         vchiq_dump_platform_use_state(state);
2789 }
2790
2791 VCHIQ_STATUS_T
2792 vchiq_check_service(VCHIQ_SERVICE_T *service)
2793 {
2794         VCHIQ_ARM_STATE_T *arm_state;
2795         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2796
2797         if (!service || !service->state)
2798                 goto out;
2799
2800         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2801
2802         arm_state = vchiq_platform_get_arm_state(service->state);
2803
2804         read_lock_bh(&arm_state->susp_res_lock);
2805         if (service->service_use_count)
2806                 ret = VCHIQ_SUCCESS;
2807         read_unlock_bh(&arm_state->susp_res_lock);
2808
2809         if (ret == VCHIQ_ERROR) {
2810                 vchiq_log_error(vchiq_susp_log_level,
2811                         "%s ERROR - %c%c%c%c:%d service count %d, "
2812                         "state count %d, videocore suspend state %s", __func__,
2813                         VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2814                         service->client_id, service->service_use_count,
2815                         arm_state->videocore_use_count,
2816                         suspend_state_names[arm_state->vc_suspend_state +
2817                                                 VC_SUSPEND_NUM_OFFSET]);
2818                 vchiq_dump_service_use_state(service->state);
2819         }
2820 out:
2821         return ret;
2822 }
2823
2824 /* stub functions */
2825 void vchiq_on_remote_use_active(VCHIQ_STATE_T *state)
2826 {
2827         (void)state;
2828 }
2829
2830 void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
2831         VCHIQ_CONNSTATE_T oldstate, VCHIQ_CONNSTATE_T newstate)
2832 {
2833         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2834         vchiq_log_info(vchiq_susp_log_level, "%d: %s->%s", state->id,
2835                 get_conn_state_name(oldstate), get_conn_state_name(newstate));
2836         if (state->conn_state == VCHIQ_CONNSTATE_CONNECTED) {
2837                 write_lock_bh(&arm_state->susp_res_lock);
2838                 if (!arm_state->first_connect) {
2839                         char threadname[16];
2840                         arm_state->first_connect = 1;
2841                         write_unlock_bh(&arm_state->susp_res_lock);
2842                         snprintf(threadname, sizeof(threadname), "vchiq-keep/%d",
2843                                 state->id);
2844                         arm_state->ka_thread = kthread_create(
2845                                 &vchiq_keepalive_thread_func,
2846                                 (void *)state,
2847                                 threadname);
2848                         if (IS_ERR(arm_state->ka_thread)) {
2849                                 vchiq_log_error(vchiq_susp_log_level,
2850                                         "vchiq: FATAL: couldn't create thread %s",
2851                                         threadname);
2852                         } else {
2853                                 wake_up_process(arm_state->ka_thread);
2854                         }
2855                 } else
2856                         write_unlock_bh(&arm_state->susp_res_lock);
2857         }
2858 }
2859
2860 static int vchiq_probe(struct platform_device *pdev)
2861 {
2862         struct device_node *fw_node;
2863         struct rpi_firmware *fw;
2864         int err;
2865         void *ptr_err;
2866
2867         fw_node = of_parse_phandle(pdev->dev.of_node, "firmware", 0);
2868         if (!fw_node) {
2869                 dev_err(&pdev->dev, "Missing firmware node\n");
2870                 return -ENOENT;
2871         }
2872
2873         fw = rpi_firmware_get(fw_node);
2874         of_node_put(fw_node);
2875         if (!fw)
2876                 return -EPROBE_DEFER;
2877
2878         platform_set_drvdata(pdev, fw);
2879
2880         err = vchiq_platform_init(pdev, &g_state);
2881         if (err != 0)
2882                 goto failed_platform_init;
2883
2884         err = alloc_chrdev_region(&vchiq_devid, VCHIQ_MINOR, 1, DEVICE_NAME);
2885         if (err != 0) {
2886                 vchiq_log_error(vchiq_arm_log_level,
2887                         "Unable to allocate device number");
2888                 goto failed_platform_init;
2889         }
2890         cdev_init(&vchiq_cdev, &vchiq_fops);
2891         vchiq_cdev.owner = THIS_MODULE;
2892         err = cdev_add(&vchiq_cdev, vchiq_devid, 1);
2893         if (err != 0) {
2894                 vchiq_log_error(vchiq_arm_log_level,
2895                         "Unable to register device");
2896                 goto failed_cdev_add;
2897         }
2898
2899         /* create sysfs entries */
2900         vchiq_class = class_create(THIS_MODULE, DEVICE_NAME);
2901         ptr_err = vchiq_class;
2902         if (IS_ERR(ptr_err))
2903                 goto failed_class_create;
2904
2905         vchiq_dev = device_create(vchiq_class, NULL,
2906                 vchiq_devid, NULL, "vchiq");
2907         ptr_err = vchiq_dev;
2908         if (IS_ERR(ptr_err))
2909                 goto failed_device_create;
2910
2911         /* create debugfs entries */
2912         err = vchiq_debugfs_init();
2913         if (err != 0)
2914                 goto failed_debugfs_init;
2915
2916         vchiq_log_info(vchiq_arm_log_level,
2917                 "vchiq: initialised - version %d (min %d), device %d.%d",
2918                 VCHIQ_VERSION, VCHIQ_VERSION_MIN,
2919                 MAJOR(vchiq_devid), MINOR(vchiq_devid));
2920
2921         return 0;
2922
2923 failed_debugfs_init:
2924         device_destroy(vchiq_class, vchiq_devid);
2925 failed_device_create:
2926         class_destroy(vchiq_class);
2927 failed_class_create:
2928         cdev_del(&vchiq_cdev);
2929         err = PTR_ERR(ptr_err);
2930 failed_cdev_add:
2931         unregister_chrdev_region(vchiq_devid, 1);
2932 failed_platform_init:
2933         vchiq_log_warning(vchiq_arm_log_level, "could not load vchiq");
2934         return err;
2935 }
2936
2937 static int vchiq_remove(struct platform_device *pdev)
2938 {
2939         vchiq_debugfs_deinit();
2940         device_destroy(vchiq_class, vchiq_devid);
2941         class_destroy(vchiq_class);
2942         cdev_del(&vchiq_cdev);
2943         unregister_chrdev_region(vchiq_devid, 1);
2944
2945         return 0;
2946 }
2947
2948 static const struct of_device_id vchiq_of_match[] = {
2949         { .compatible = "brcm,bcm2835-vchiq", },
2950         {},
2951 };
2952 MODULE_DEVICE_TABLE(of, vchiq_of_match);
2953
2954 static struct platform_driver vchiq_driver = {
2955         .driver = {
2956                 .name = "bcm2835_vchiq",
2957                 .of_match_table = vchiq_of_match,
2958         },
2959         .probe = vchiq_probe,
2960         .remove = vchiq_remove,
2961 };
2962 module_platform_driver(vchiq_driver);
2963
2964 MODULE_LICENSE("GPL");
2965 MODULE_DESCRIPTION("Videocore VCHIQ driver");
2966 MODULE_AUTHOR("Broadcom Corporation");