drivers/hid/hid-cp2112.c

   1 /*
   2  * hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
   3  * Copyright (c) 2013,2014 Uplogix, Inc.
   4  * David Barksdale <dbarksdale@uplogix.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 /*
  17  * The Silicon Labs CP2112 chip is a USB HID device which provides an
  18  * SMBus controller for talking to slave devices and 8 GPIO pins. The
  19  * host communicates with the CP2112 via raw HID reports.
  20  *
  21  * Data Sheet:
  22  *   http://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
  23  * Programming Interface Specification:
  24  *   http://www.silabs.com/Support%20Documents/TechnicalDocs/AN495.pdf
  25  */
  26
  27 #include <linux/gpio.h>
  28 #include <linux/gpio/driver.h>
  29 #include <linux/hid.h>
  30 #include <linux/i2c.h>
  31 #include <linux/module.h>
  32 #include <linux/nls.h>
  33 #include <linux/usb/ch9.h>
  34 #include "hid-ids.h"
  35
  36 #define CP2112_REPORT_MAX_LENGTH                64
  37 #define CP2112_GPIO_CONFIG_LENGTH               5
  38 #define CP2112_GPIO_GET_LENGTH                  2
  39 #define CP2112_GPIO_SET_LENGTH                  3
  40
  41 enum {
  42         CP2112_GPIO_CONFIG              = 0x02,
  43         CP2112_GPIO_GET                 = 0x03,
  44         CP2112_GPIO_SET                 = 0x04,
  45         CP2112_GET_VERSION_INFO         = 0x05,
  46         CP2112_SMBUS_CONFIG             = 0x06,
  47         CP2112_DATA_READ_REQUEST        = 0x10,
  48         CP2112_DATA_WRITE_READ_REQUEST  = 0x11,
  49         CP2112_DATA_READ_FORCE_SEND     = 0x12,
  50         CP2112_DATA_READ_RESPONSE       = 0x13,
  51         CP2112_DATA_WRITE_REQUEST       = 0x14,
  52         CP2112_TRANSFER_STATUS_REQUEST  = 0x15,
  53         CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
  54         CP2112_CANCEL_TRANSFER          = 0x17,
  55         CP2112_LOCK_BYTE                = 0x20,
  56         CP2112_USB_CONFIG               = 0x21,
  57         CP2112_MANUFACTURER_STRING      = 0x22,
  58         CP2112_PRODUCT_STRING           = 0x23,
  59         CP2112_SERIAL_STRING            = 0x24,
  60 };
  61
  62 enum {
  63         STATUS0_IDLE            = 0x00,
  64         STATUS0_BUSY            = 0x01,
  65         STATUS0_COMPLETE        = 0x02,
  66         STATUS0_ERROR           = 0x03,
  67 };
  68
  69 enum {
  70         STATUS1_TIMEOUT_NACK            = 0x00,
  71         STATUS1_TIMEOUT_BUS             = 0x01,
  72         STATUS1_ARBITRATION_LOST        = 0x02,
  73         STATUS1_READ_INCOMPLETE         = 0x03,
  74         STATUS1_WRITE_INCOMPLETE        = 0x04,
  75         STATUS1_SUCCESS                 = 0x05,
  76 };
  77
  78 struct cp2112_smbus_config_report {
  79         u8 report;              /* CP2112_SMBUS_CONFIG */
  80         __be32 clock_speed;     /* Hz */
  81         u8 device_address;      /* Stored in the upper 7 bits */
  82         u8 auto_send_read;      /* 1 = enabled, 0 = disabled */
  83         __be16 write_timeout;   /* ms, 0 = no timeout */
  84         __be16 read_timeout;    /* ms, 0 = no timeout */
  85         u8 scl_low_timeout;     /* 1 = enabled, 0 = disabled */
  86         __be16 retry_time;      /* # of retries, 0 = no limit */
  87 } __packed;
  88
  89 struct cp2112_usb_config_report {
  90         u8 report;      /* CP2112_USB_CONFIG */
  91         __le16 vid;     /* Vendor ID */
  92         __le16 pid;     /* Product ID */
  93         u8 max_power;   /* Power requested in 2mA units */
  94         u8 power_mode;  /* 0x00 = bus powered
  95                            0x01 = self powered & regulator off
  96                            0x02 = self powered & regulator on */
  97         u8 release_major;
  98         u8 release_minor;
  99         u8 mask;        /* What fields to program */
 100 } __packed;
 101
 102 struct cp2112_read_req_report {
 103         u8 report;      /* CP2112_DATA_READ_REQUEST */
 104         u8 slave_address;
 105         __be16 length;
 106 } __packed;
 107
 108 struct cp2112_write_read_req_report {
 109         u8 report;      /* CP2112_DATA_WRITE_READ_REQUEST */
 110         u8 slave_address;
 111         __be16 length;
 112         u8 target_address_length;
 113         u8 target_address[16];
 114 } __packed;
 115
 116 struct cp2112_write_req_report {
 117         u8 report;      /* CP2112_DATA_WRITE_REQUEST */
 118         u8 slave_address;
 119         u8 length;
 120         u8 data[61];
 121 } __packed;
 122
 123 struct cp2112_force_read_report {
 124         u8 report;      /* CP2112_DATA_READ_FORCE_SEND */
 125         __be16 length;
 126 } __packed;
 127
 128 struct cp2112_xfer_status_report {
 129         u8 report;      /* CP2112_TRANSFER_STATUS_RESPONSE */
 130         u8 status0;     /* STATUS0_* */
 131         u8 status1;     /* STATUS1_* */
 132         __be16 retries;
 133         __be16 length;
 134 } __packed;
 135
 136 struct cp2112_string_report {
 137         u8 dummy;               /* force .string to be aligned */
 138         u8 report;              /* CP2112_*_STRING */
 139         u8 length;              /* length in bytes of everyting after .report */
 140         u8 type;                /* USB_DT_STRING */
 141         wchar_t string[30];     /* UTF16_LITTLE_ENDIAN string */
 142 } __packed;
 143
 144 /* Number of times to request transfer status before giving up waiting for a
 145    transfer to complete. This may need to be changed if SMBUS clock, retries,
 146    or read/write/scl_low timeout settings are changed. */
 147 static const int XFER_STATUS_RETRIES = 10;
 148
 149 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
 150    CP2112_TRANSFER_STATUS_RESPONSE. */
 151 static const int RESPONSE_TIMEOUT = 50;
 152
 153 static const struct hid_device_id cp2112_devices[] = {
 154         { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
 155         { }
 156 };
 157 MODULE_DEVICE_TABLE(hid, cp2112_devices);
 158
 159 struct cp2112_device {
 160         struct i2c_adapter adap;
 161         struct hid_device *hdev;
 162         wait_queue_head_t wait;
 163         u8 read_data[61];
 164         u8 read_length;
 165         u8 hwversion;
 166         int xfer_status;
 167         atomic_t read_avail;
 168         atomic_t xfer_avail;
 169         struct gpio_chip gc;
 170         u8 *in_out_buffer;
 171         spinlock_t lock;
 172
 173         struct gpio_desc *desc[8];
 174         bool gpio_poll;
 175         struct delayed_work gpio_poll_worker;
 176         unsigned long irq_mask;
 177         u8 gpio_prev_state;
 178 };
 179
 180 static int gpio_push_pull = 0xFF;
 181 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
 182 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
 183
 184 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 185 {
 186         struct cp2112_device *dev = gpiochip_get_data(chip);
 187         struct hid_device *hdev = dev->hdev;
 188         u8 *buf = dev->in_out_buffer;
 189         unsigned long flags;
 190         int ret;
 191
 192         spin_lock_irqsave(&dev->lock, flags);
 193
 194         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 195                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 196                                  HID_REQ_GET_REPORT);
 197         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 198                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 199                 goto exit;
 200         }
 201
 202         buf[1] &= ~(1 << offset);
 203         buf[2] = gpio_push_pull;
 204
 205         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 206                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 207                                  HID_REQ_SET_REPORT);
 208         if (ret < 0) {
 209                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 210                 goto exit;
 211         }
 212
 213         ret = 0;
 214
 215 exit:
 216         spin_unlock_irqrestore(&dev->lock, flags);
 217         return ret <= 0 ? ret : -EIO;
 218 }
 219
 220 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 221 {
 222         struct cp2112_device *dev = gpiochip_get_data(chip);
 223         struct hid_device *hdev = dev->hdev;
 224         u8 *buf = dev->in_out_buffer;
 225         unsigned long flags;
 226         int ret;
 227
 228         spin_lock_irqsave(&dev->lock, flags);
 229
 230         buf[0] = CP2112_GPIO_SET;
 231         buf[1] = value ? 0xff : 0;
 232         buf[2] = 1 << offset;
 233
 234         ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
 235                                  CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
 236                                  HID_REQ_SET_REPORT);
 237         if (ret < 0)
 238                 hid_err(hdev, "error setting GPIO values: %d\n", ret);
 239
 240         spin_unlock_irqrestore(&dev->lock, flags);
 241 }
 242
 243 static int cp2112_gpio_get_all(struct gpio_chip *chip)
 244 {
 245         struct cp2112_device *dev = gpiochip_get_data(chip);
 246         struct hid_device *hdev = dev->hdev;
 247         u8 *buf = dev->in_out_buffer;
 248         unsigned long flags;
 249         int ret;
 250
 251         spin_lock_irqsave(&dev->lock, flags);
 252
 253         ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
 254                                  CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
 255                                  HID_REQ_GET_REPORT);
 256         if (ret != CP2112_GPIO_GET_LENGTH) {
 257                 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
 258                 ret = ret < 0 ? ret : -EIO;
 259                 goto exit;
 260         }
 261
 262         ret = buf[1];
 263
 264 exit:
 265         spin_unlock_irqrestore(&dev->lock, flags);
 266
 267         return ret;
 268 }
 269
 270 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
 271 {
 272         int ret;
 273
 274         ret = cp2112_gpio_get_all(chip);
 275         if (ret < 0)
 276                 return ret;
 277
 278         return (ret >> offset) & 1;
 279 }
 280
 281 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
 282                                         unsigned offset, int value)
 283 {
 284         struct cp2112_device *dev = gpiochip_get_data(chip);
 285         struct hid_device *hdev = dev->hdev;
 286         u8 *buf = dev->in_out_buffer;
 287         unsigned long flags;
 288         int ret;
 289
 290         spin_lock_irqsave(&dev->lock, flags);
 291
 292         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 293                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 294                                  HID_REQ_GET_REPORT);
 295         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 296                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 297                 goto fail;
 298         }
 299
 300         buf[1] |= 1 << offset;
 301         buf[2] = gpio_push_pull;
 302
 303         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 304                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 305                                  HID_REQ_SET_REPORT);
 306         if (ret < 0) {
 307                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 308                 goto fail;
 309         }
 310
 311         spin_unlock_irqrestore(&dev->lock, flags);
 312
 313         /*
 314          * Set gpio value when output direction is already set,
 315          * as specified in AN495, Rev. 0.2, cpt. 4.4
 316          */
 317         cp2112_gpio_set(chip, offset, value);
 318
 319         return 0;
 320
 321 fail:
 322         spin_unlock_irqrestore(&dev->lock, flags);
 323         return ret < 0 ? ret : -EIO;
 324 }
 325
 326 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
 327                           u8 *data, size_t count, unsigned char report_type)
 328 {
 329         u8 *buf;
 330         int ret;
 331
 332         buf = kmalloc(count, GFP_KERNEL);
 333         if (!buf)
 334                 return -ENOMEM;
 335
 336         ret = hid_hw_raw_request(hdev, report_number, buf, count,
 337                                        report_type, HID_REQ_GET_REPORT);
 338         memcpy(data, buf, count);
 339         kfree(buf);
 340         return ret;
 341 }
 342
 343 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
 344                              unsigned char report_type)
 345 {
 346         u8 *buf;
 347         int ret;
 348
 349         buf = kmemdup(data, count, GFP_KERNEL);
 350         if (!buf)
 351                 return -ENOMEM;
 352
 353         if (report_type == HID_OUTPUT_REPORT)
 354                 ret = hid_hw_output_report(hdev, buf, count);
 355         else
 356                 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
 357                                 HID_REQ_SET_REPORT);
 358
 359         kfree(buf);
 360         return ret;
 361 }
 362
 363 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
 364 {
 365         int ret = 0;
 366
 367         /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
 368          * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
 369          * come in cp2112_raw_event or timeout. There will only be one of these
 370          * in flight at any one time. The timeout is extremely large and is a
 371          * last resort if the CP2112 has died. If we do timeout we don't expect
 372          * to receive the response which would cause data races, it's not like
 373          * we can do anything about it anyway.
 374          */
 375         ret = wait_event_interruptible_timeout(dev->wait,
 376                 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
 377         if (-ERESTARTSYS == ret)
 378                 return ret;
 379         if (!ret)
 380                 return -ETIMEDOUT;
 381
 382         atomic_set(avail, 0);
 383         return 0;
 384 }
 385
 386 static int cp2112_xfer_status(struct cp2112_device *dev)
 387 {
 388         struct hid_device *hdev = dev->hdev;
 389         u8 buf[2];
 390         int ret;
 391
 392         buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
 393         buf[1] = 0x01;
 394         atomic_set(&dev->xfer_avail, 0);
 395
 396         ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 397         if (ret < 0) {
 398                 hid_warn(hdev, "Error requesting status: %d\n", ret);
 399                 return ret;
 400         }
 401
 402         ret = cp2112_wait(dev, &dev->xfer_avail);
 403         if (ret)
 404                 return ret;
 405
 406         return dev->xfer_status;
 407 }
 408
 409 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
 410 {
 411         struct hid_device *hdev = dev->hdev;
 412         struct cp2112_force_read_report report;
 413         int ret;
 414
 415         if (size > sizeof(dev->read_data))
 416                 size = sizeof(dev->read_data);
 417         report.report = CP2112_DATA_READ_FORCE_SEND;
 418         report.length = cpu_to_be16(size);
 419
 420         atomic_set(&dev->read_avail, 0);
 421
 422         ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
 423                                 HID_OUTPUT_REPORT);
 424         if (ret < 0) {
 425                 hid_warn(hdev, "Error requesting data: %d\n", ret);
 426                 return ret;
 427         }
 428
 429         ret = cp2112_wait(dev, &dev->read_avail);
 430         if (ret)
 431                 return ret;
 432
 433         hid_dbg(hdev, "read %d of %zd bytes requested\n",
 434                 dev->read_length, size);
 435
 436         if (size > dev->read_length)
 437                 size = dev->read_length;
 438
 439         memcpy(data, dev->read_data, size);
 440         return dev->read_length;
 441 }
 442
 443 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
 444 {
 445         struct cp2112_read_req_report *report = buf;
 446
 447         if (length < 1 || length > 512)
 448                 return -EINVAL;
 449
 450         report->report = CP2112_DATA_READ_REQUEST;
 451         report->slave_address = slave_address << 1;
 452         report->length = cpu_to_be16(length);
 453         return sizeof(*report);
 454 }
 455
 456 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
 457                                  u8 command, u8 *data, u8 data_length)
 458 {
 459         struct cp2112_write_read_req_report *report = buf;
 460
 461         if (length < 1 || length > 512
 462             || data_length > sizeof(report->target_address) - 1)
 463                 return -EINVAL;
 464
 465         report->report = CP2112_DATA_WRITE_READ_REQUEST;
 466         report->slave_address = slave_address << 1;
 467         report->length = cpu_to_be16(length);
 468         report->target_address_length = data_length + 1;
 469         report->target_address[0] = command;
 470         memcpy(&report->target_address[1], data, data_length);
 471         return data_length + 6;
 472 }
 473
 474 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
 475                             u8 data_length)
 476 {
 477         struct cp2112_write_req_report *report = buf;
 478
 479         if (data_length > sizeof(report->data) - 1)
 480                 return -EINVAL;
 481
 482         report->report = CP2112_DATA_WRITE_REQUEST;
 483         report->slave_address = slave_address << 1;
 484         report->length = data_length + 1;
 485         report->data[0] = command;
 486         memcpy(&report->data[1], data, data_length);
 487         return data_length + 4;
 488 }
 489
 490 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
 491                                 u8 data_length)
 492 {
 493         struct cp2112_write_req_report *report = buf;
 494
 495         if (data_length > sizeof(report->data))
 496                 return -EINVAL;
 497
 498         report->report = CP2112_DATA_WRITE_REQUEST;
 499         report->slave_address = slave_address << 1;
 500         report->length = data_length;
 501         memcpy(report->data, data, data_length);
 502         return data_length + 3;
 503 }
 504
 505 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
 506                                      u8 *addr, int addr_length,
 507                                      int read_length)
 508 {
 509         struct cp2112_write_read_req_report *report = buf;
 510
 511         if (read_length < 1 || read_length > 512 ||
 512             addr_length > sizeof(report->target_address))
 513                 return -EINVAL;
 514
 515         report->report = CP2112_DATA_WRITE_READ_REQUEST;
 516         report->slave_address = slave_address << 1;
 517         report->length = cpu_to_be16(read_length);
 518         report->target_address_length = addr_length;
 519         memcpy(report->target_address, addr, addr_length);
 520         return addr_length + 5;
 521 }
 522
 523 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 524                            int num)
 525 {
 526         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 527         struct hid_device *hdev = dev->hdev;
 528         u8 buf[64];
 529         ssize_t count;
 530         ssize_t read_length = 0;
 531         u8 *read_buf = NULL;
 532         unsigned int retries;
 533         int ret;
 534
 535         hid_dbg(hdev, "I2C %d messages\n", num);
 536
 537         if (num == 1) {
 538                 if (msgs->flags & I2C_M_RD) {
 539                         hid_dbg(hdev, "I2C read %#04x len %d\n",
 540                                 msgs->addr, msgs->len);
 541                         read_length = msgs->len;
 542                         read_buf = msgs->buf;
 543                         count = cp2112_read_req(buf, msgs->addr, msgs->len);
 544                 } else {
 545                         hid_dbg(hdev, "I2C write %#04x len %d\n",
 546                                 msgs->addr, msgs->len);
 547                         count = cp2112_i2c_write_req(buf, msgs->addr,
 548                                                      msgs->buf, msgs->len);
 549                 }
 550                 if (count < 0)
 551                         return count;
 552         } else if (dev->hwversion > 1 &&  /* no repeated start in rev 1 */
 553                    num == 2 &&
 554                    msgs[0].addr == msgs[1].addr &&
 555                    !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
 556                 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
 557                         msgs[0].addr, msgs[0].len, msgs[1].len);
 558                 read_length = msgs[1].len;
 559                 read_buf = msgs[1].buf;
 560                 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
 561                                 msgs[0].buf, msgs[0].len, msgs[1].len);
 562                 if (count < 0)
 563                         return count;
 564         } else {
 565                 hid_err(hdev,
 566                         "Multi-message I2C transactions not supported\n");
 567                 return -EOPNOTSUPP;
 568         }
 569
 570         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 571         if (ret < 0) {
 572                 hid_err(hdev, "power management error: %d\n", ret);
 573                 return ret;
 574         }
 575
 576         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 577         if (ret < 0) {
 578                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 579                 goto power_normal;
 580         }
 581
 582         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 583                 ret = cp2112_xfer_status(dev);
 584                 if (-EBUSY == ret)
 585                         continue;
 586                 if (ret < 0)
 587                         goto power_normal;
 588                 break;
 589         }
 590
 591         if (XFER_STATUS_RETRIES <= retries) {
 592                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 593                 buf[0] = CP2112_CANCEL_TRANSFER;
 594                 buf[1] = 0x01;
 595
 596                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 597                 if (ret < 0)
 598                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 599                                  ret);
 600
 601                 ret = -ETIMEDOUT;
 602                 goto power_normal;
 603         }
 604
 605         for (count = 0; count < read_length;) {
 606                 ret = cp2112_read(dev, read_buf + count, read_length - count);
 607                 if (ret < 0)
 608                         goto power_normal;
 609                 if (ret == 0) {
 610                         hid_err(hdev, "read returned 0\n");
 611                         ret = -EIO;
 612                         goto power_normal;
 613                 }
 614                 count += ret;
 615                 if (count > read_length) {
 616                         /*
 617                          * The hardware returned too much data.
 618                          * This is mostly harmless because cp2112_read()
 619                          * has a limit check so didn't overrun our
 620                          * buffer.  Nevertheless, we return an error
 621                          * because something is seriously wrong and
 622                          * it shouldn't go unnoticed.
 623                          */
 624                         hid_err(hdev, "long read: %d > %zd\n",
 625                                 ret, read_length - count + ret);
 626                         ret = -EIO;
 627                         goto power_normal;
 628                 }
 629         }
 630
 631         /* return the number of transferred messages */
 632         ret = num;
 633
 634 power_normal:
 635         hid_hw_power(hdev, PM_HINT_NORMAL);
 636         hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
 637         return ret;
 638 }
 639
 640 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
 641                        unsigned short flags, char read_write, u8 command,
 642                        int size, union i2c_smbus_data *data)
 643 {
 644         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 645         struct hid_device *hdev = dev->hdev;
 646         u8 buf[64];
 647         __le16 word;
 648         ssize_t count;
 649         size_t read_length = 0;
 650         unsigned int retries;
 651         int ret;
 652
 653         hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
 654                 read_write == I2C_SMBUS_WRITE ? "write" : "read",
 655                 addr, flags, command, size);
 656
 657         switch (size) {
 658         case I2C_SMBUS_BYTE:
 659                 read_length = 1;
 660
 661                 if (I2C_SMBUS_READ == read_write)
 662                         count = cp2112_read_req(buf, addr, read_length);
 663                 else
 664                         count = cp2112_write_req(buf, addr, command, NULL,
 665                                                  0);
 666                 break;
 667         case I2C_SMBUS_BYTE_DATA:
 668                 read_length = 1;
 669
 670                 if (I2C_SMBUS_READ == read_write)
 671                         count = cp2112_write_read_req(buf, addr, read_length,
 672                                                       command, NULL, 0);
 673                 else
 674                         count = cp2112_write_req(buf, addr, command,
 675                                                  &data->byte, 1);
 676                 break;
 677         case I2C_SMBUS_WORD_DATA:
 678                 read_length = 2;
 679                 word = cpu_to_le16(data->word);
 680
 681                 if (I2C_SMBUS_READ == read_write)
 682                         count = cp2112_write_read_req(buf, addr, read_length,
 683                                                       command, NULL, 0);
 684                 else
 685                         count = cp2112_write_req(buf, addr, command,
 686                                                  (u8 *)&word, 2);
 687                 break;
 688         case I2C_SMBUS_PROC_CALL:
 689                 size = I2C_SMBUS_WORD_DATA;
 690                 read_write = I2C_SMBUS_READ;
 691                 read_length = 2;
 692                 word = cpu_to_le16(data->word);
 693
 694                 count = cp2112_write_read_req(buf, addr, read_length, command,
 695                                               (u8 *)&word, 2);
 696                 break;
 697         case I2C_SMBUS_I2C_BLOCK_DATA:
 698                 size = I2C_SMBUS_BLOCK_DATA;
 699                 /* fallthrough */
 700         case I2C_SMBUS_BLOCK_DATA:
 701                 if (I2C_SMBUS_READ == read_write) {
 702                         count = cp2112_write_read_req(buf, addr,
 703                                                       I2C_SMBUS_BLOCK_MAX,
 704                                                       command, NULL, 0);
 705                 } else {
 706                         count = cp2112_write_req(buf, addr, command,
 707                                                  data->block,
 708                                                  data->block[0] + 1);
 709                 }
 710                 break;
 711         case I2C_SMBUS_BLOCK_PROC_CALL:
 712                 size = I2C_SMBUS_BLOCK_DATA;
 713                 read_write = I2C_SMBUS_READ;
 714
 715                 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
 716                                               command, data->block,
 717                                               data->block[0] + 1);
 718                 break;
 719         default:
 720                 hid_warn(hdev, "Unsupported transaction %d\n", size);
 721                 return -EOPNOTSUPP;
 722         }
 723
 724         if (count < 0)
 725                 return count;
 726
 727         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 728         if (ret < 0) {
 729                 hid_err(hdev, "power management error: %d\n", ret);
 730                 return ret;
 731         }
 732
 733         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 734         if (ret < 0) {
 735                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 736                 goto power_normal;
 737         }
 738
 739         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 740                 ret = cp2112_xfer_status(dev);
 741                 if (-EBUSY == ret)
 742                         continue;
 743                 if (ret < 0)
 744                         goto power_normal;
 745                 break;
 746         }
 747
 748         if (XFER_STATUS_RETRIES <= retries) {
 749                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 750                 buf[0] = CP2112_CANCEL_TRANSFER;
 751                 buf[1] = 0x01;
 752
 753                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 754                 if (ret < 0)
 755                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 756                                  ret);
 757
 758                 ret = -ETIMEDOUT;
 759                 goto power_normal;
 760         }
 761
 762         if (I2C_SMBUS_WRITE == read_write) {
 763                 ret = 0;
 764                 goto power_normal;
 765         }
 766
 767         if (I2C_SMBUS_BLOCK_DATA == size)
 768                 read_length = ret;
 769
 770         ret = cp2112_read(dev, buf, read_length);
 771         if (ret < 0)
 772                 goto power_normal;
 773         if (ret != read_length) {
 774                 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
 775                 ret = -EIO;
 776                 goto power_normal;
 777         }
 778
 779         switch (size) {
 780         case I2C_SMBUS_BYTE:
 781         case I2C_SMBUS_BYTE_DATA:
 782                 data->byte = buf[0];
 783                 break;
 784         case I2C_SMBUS_WORD_DATA:
 785                 data->word = le16_to_cpup((__le16 *)buf);
 786                 break;
 787         case I2C_SMBUS_BLOCK_DATA:
 788                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
 789                         ret = -EPROTO;
 790                         goto power_normal;
 791                 }
 792
 793                 memcpy(data->block, buf, read_length);
 794                 break;
 795         }
 796
 797         ret = 0;
 798 power_normal:
 799         hid_hw_power(hdev, PM_HINT_NORMAL);
 800         hid_dbg(hdev, "transfer finished: %d\n", ret);
 801         return ret;
 802 }
 803
 804 static u32 cp2112_functionality(struct i2c_adapter *adap)
 805 {
 806         return I2C_FUNC_I2C |
 807                 I2C_FUNC_SMBUS_BYTE |
 808                 I2C_FUNC_SMBUS_BYTE_DATA |
 809                 I2C_FUNC_SMBUS_WORD_DATA |
 810                 I2C_FUNC_SMBUS_BLOCK_DATA |
 811                 I2C_FUNC_SMBUS_I2C_BLOCK |
 812                 I2C_FUNC_SMBUS_PROC_CALL |
 813                 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 814 }
 815
 816 static const struct i2c_algorithm smbus_algorithm = {
 817         .master_xfer    = cp2112_i2c_xfer,
 818         .smbus_xfer     = cp2112_xfer,
 819         .functionality  = cp2112_functionality,
 820 };
 821
 822 static int cp2112_get_usb_config(struct hid_device *hdev,
 823                                  struct cp2112_usb_config_report *cfg)
 824 {
 825         int ret;
 826
 827         ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
 828                              HID_FEATURE_REPORT);
 829         if (ret != sizeof(*cfg)) {
 830                 hid_err(hdev, "error reading usb config: %d\n", ret);
 831                 if (ret < 0)
 832                         return ret;
 833                 return -EIO;
 834         }
 835
 836         return 0;
 837 }
 838
 839 static int cp2112_set_usb_config(struct hid_device *hdev,
 840                                  struct cp2112_usb_config_report *cfg)
 841 {
 842         int ret;
 843
 844         BUG_ON(cfg->report != CP2112_USB_CONFIG);
 845
 846         ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
 847                                 HID_FEATURE_REPORT);
 848         if (ret != sizeof(*cfg)) {
 849                 hid_err(hdev, "error writing usb config: %d\n", ret);
 850                 if (ret < 0)
 851                         return ret;
 852                 return -EIO;
 853         }
 854
 855         return 0;
 856 }
 857
 858 static void chmod_sysfs_attrs(struct hid_device *hdev);
 859
 860 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
 861 static ssize_t name##_store(struct device *kdev, \
 862                             struct device_attribute *attr, const char *buf, \
 863                             size_t count) \
 864 { \
 865         struct hid_device *hdev = to_hid_device(kdev); \
 866         struct cp2112_usb_config_report cfg; \
 867         int ret = cp2112_get_usb_config(hdev, &cfg); \
 868         if (ret) \
 869                 return ret; \
 870         store; \
 871         ret = cp2112_set_usb_config(hdev, &cfg); \
 872         if (ret) \
 873                 return ret; \
 874         chmod_sysfs_attrs(hdev); \
 875         return count; \
 876 } \
 877 static ssize_t name##_show(struct device *kdev, \
 878                            struct device_attribute *attr, char *buf) \
 879 { \
 880         struct hid_device *hdev = to_hid_device(kdev); \
 881         struct cp2112_usb_config_report cfg; \
 882         int ret = cp2112_get_usb_config(hdev, &cfg); \
 883         if (ret) \
 884                 return ret; \
 885         return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
 886 } \
 887 static DEVICE_ATTR_RW(name);
 888
 889 CP2112_CONFIG_ATTR(vendor_id, ({
 890         u16 vid;
 891
 892         if (sscanf(buf, "%hi", &vid) != 1)
 893                 return -EINVAL;
 894
 895         cfg.vid = cpu_to_le16(vid);
 896         cfg.mask = 0x01;
 897 }), "0x%04x\n", le16_to_cpu(cfg.vid));
 898
 899 CP2112_CONFIG_ATTR(product_id, ({
 900         u16 pid;
 901
 902         if (sscanf(buf, "%hi", &pid) != 1)
 903                 return -EINVAL;
 904
 905         cfg.pid = cpu_to_le16(pid);
 906         cfg.mask = 0x02;
 907 }), "0x%04x\n", le16_to_cpu(cfg.pid));
 908
 909 CP2112_CONFIG_ATTR(max_power, ({
 910         int mA;
 911
 912         if (sscanf(buf, "%i", &mA) != 1)
 913                 return -EINVAL;
 914
 915         cfg.max_power = (mA + 1) / 2;
 916         cfg.mask = 0x04;
 917 }), "%u mA\n", cfg.max_power * 2);
 918
 919 CP2112_CONFIG_ATTR(power_mode, ({
 920         if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
 921                 return -EINVAL;
 922
 923         cfg.mask = 0x08;
 924 }), "%u\n", cfg.power_mode);
 925
 926 CP2112_CONFIG_ATTR(release_version, ({
 927         if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
 928             != 2)
 929                 return -EINVAL;
 930
 931         cfg.mask = 0x10;
 932 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
 933
 934 #undef CP2112_CONFIG_ATTR
 935
 936 struct cp2112_pstring_attribute {
 937         struct device_attribute attr;
 938         unsigned char report;
 939 };
 940
 941 static ssize_t pstr_store(struct device *kdev,
 942                           struct device_attribute *kattr, const char *buf,
 943                           size_t count)
 944 {
 945         struct hid_device *hdev = to_hid_device(kdev);
 946         struct cp2112_pstring_attribute *attr =
 947                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 948         struct cp2112_string_report report;
 949         int ret;
 950
 951         memset(&report, 0, sizeof(report));
 952
 953         ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 954                               report.string, ARRAY_SIZE(report.string));
 955         report.report = attr->report;
 956         report.length = ret * sizeof(report.string[0]) + 2;
 957         report.type = USB_DT_STRING;
 958
 959         ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 960                                 HID_FEATURE_REPORT);
 961         if (ret != report.length + 1) {
 962                 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 963                         ret);
 964                 if (ret < 0)
 965                         return ret;
 966                 return -EIO;
 967         }
 968
 969         chmod_sysfs_attrs(hdev);
 970         return count;
 971 }
 972
 973 static ssize_t pstr_show(struct device *kdev,
 974                          struct device_attribute *kattr, char *buf)
 975 {
 976         struct hid_device *hdev = to_hid_device(kdev);
 977         struct cp2112_pstring_attribute *attr =
 978                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 979         struct cp2112_string_report report;
 980         u8 length;
 981         int ret;
 982
 983         ret = cp2112_hid_get(hdev, attr->report, &report.report,
 984                              sizeof(report) - 1, HID_FEATURE_REPORT);
 985         if (ret < 3) {
 986                 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
 987                         ret);
 988                 if (ret < 0)
 989                         return ret;
 990                 return -EIO;
 991         }
 992
 993         if (report.length < 2) {
 994                 hid_err(hdev, "invalid %s string length: %d\n",
 995                         kattr->attr.name, report.length);
 996                 return -EIO;
 997         }
 998
 999         length = report.length > ret - 1 ? ret - 1 : report.length;
1000         length = (length - 2) / sizeof(report.string[0]);
1001         ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1002                               PAGE_SIZE - 1);
1003         buf[ret++] = '\n';
1004         return ret;
1005 }
1006
1007 #define CP2112_PSTR_ATTR(name, _report) \
1008 static struct cp2112_pstring_attribute dev_attr_##name = { \
1009         .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1010         .report = _report, \
1011 };
1012
1013 CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1014 CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1015 CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1016
1017 #undef CP2112_PSTR_ATTR
1018
1019 static const struct attribute_group cp2112_attr_group = {
1020         .attrs = (struct attribute *[]){
1021                 &dev_attr_vendor_id.attr,
1022                 &dev_attr_product_id.attr,
1023                 &dev_attr_max_power.attr,
1024                 &dev_attr_power_mode.attr,
1025                 &dev_attr_release_version.attr,
1026                 &dev_attr_manufacturer.attr.attr,
1027                 &dev_attr_product.attr.attr,
1028                 &dev_attr_serial.attr.attr,
1029                 NULL
1030         }
1031 };
1032
1033 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1034  * PROM have already been programmed. We do not depend on this preventing
1035  * writing to these attributes since the CP2112 will simply ignore writes to
1036  * already-programmed fields. This is why there is no sense in fixing this
1037  * racy behaviour.
1038  */
1039 static void chmod_sysfs_attrs(struct hid_device *hdev)
1040 {
1041         struct attribute **attr;
1042         u8 buf[2];
1043         int ret;
1044
1045         ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1046                              HID_FEATURE_REPORT);
1047         if (ret != sizeof(buf)) {
1048                 hid_err(hdev, "error reading lock byte: %d\n", ret);
1049                 return;
1050         }
1051
1052         for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1053                 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1054                 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1055                 if (ret < 0)
1056                         hid_err(hdev, "error chmoding sysfs file %s\n",
1057                                 (*attr)->name);
1058                 buf[1] >>= 1;
1059         }
1060 }
1061
1062 static void cp2112_gpio_irq_ack(struct irq_data *d)
1063 {
1064 }
1065
1066 static void cp2112_gpio_irq_mask(struct irq_data *d)
1067 {
1068         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1069         struct cp2112_device *dev = gpiochip_get_data(gc);
1070
1071         __clear_bit(d->hwirq, &dev->irq_mask);
1072 }
1073
1074 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1075 {
1076         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1077         struct cp2112_device *dev = gpiochip_get_data(gc);
1078
1079         __set_bit(d->hwirq, &dev->irq_mask);
1080 }
1081
1082 static void cp2112_gpio_poll_callback(struct work_struct *work)
1083 {
1084         struct cp2112_device *dev = container_of(work, struct cp2112_device,
1085                                                  gpio_poll_worker.work);
1086         struct irq_data *d;
1087         u8 gpio_mask;
1088         u8 virqs = (u8)dev->irq_mask;
1089         u32 irq_type;
1090         int irq, virq, ret;
1091
1092         ret = cp2112_gpio_get_all(&dev->gc);
1093         if (ret == -ENODEV) /* the hardware has been disconnected */
1094                 return;
1095         if (ret < 0)
1096                 goto exit;
1097
1098         gpio_mask = ret;
1099
1100         while (virqs) {
1101                 virq = ffs(virqs) - 1;
1102                 virqs &= ~BIT(virq);
1103
1104                 if (!dev->gc.to_irq)
1105                         break;
1106
1107                 irq = dev->gc.to_irq(&dev->gc, virq);
1108
1109                 d = irq_get_irq_data(irq);
1110                 if (!d)
1111                         continue;
1112
1113                 irq_type = irqd_get_trigger_type(d);
1114
1115                 if (gpio_mask & BIT(virq)) {
1116                         /* Level High */
1117
1118                         if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1119                                 handle_nested_irq(irq);
1120
1121                         if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1122                             !(dev->gpio_prev_state & BIT(virq)))
1123                                 handle_nested_irq(irq);
1124                 } else {
1125                         /* Level Low */
1126
1127                         if (irq_type & IRQ_TYPE_LEVEL_LOW)
1128                                 handle_nested_irq(irq);
1129
1130                         if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1131                             (dev->gpio_prev_state & BIT(virq)))
1132                                 handle_nested_irq(irq);
1133                 }
1134         }
1135
1136         dev->gpio_prev_state = gpio_mask;
1137
1138 exit:
1139         if (dev->gpio_poll)
1140                 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1141 }
1142
1143
1144 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1145 {
1146         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1147         struct cp2112_device *dev = gpiochip_get_data(gc);
1148
1149         INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1150
1151         cp2112_gpio_direction_input(gc, d->hwirq);
1152
1153         if (!dev->gpio_poll) {
1154                 dev->gpio_poll = true;
1155                 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1156         }
1157
1158         cp2112_gpio_irq_unmask(d);
1159         return 0;
1160 }
1161
1162 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1163 {
1164         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1165         struct cp2112_device *dev = gpiochip_get_data(gc);
1166
1167         cancel_delayed_work_sync(&dev->gpio_poll_worker);
1168 }
1169
1170 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1171 {
1172         return 0;
1173 }
1174
1175 static struct irq_chip cp2112_gpio_irqchip = {
1176         .name = "cp2112-gpio",
1177         .irq_startup = cp2112_gpio_irq_startup,
1178         .irq_shutdown = cp2112_gpio_irq_shutdown,
1179         .irq_ack = cp2112_gpio_irq_ack,
1180         .irq_mask = cp2112_gpio_irq_mask,
1181         .irq_unmask = cp2112_gpio_irq_unmask,
1182         .irq_set_type = cp2112_gpio_irq_type,
1183 };
1184
1185 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1186                                               int pin)
1187 {
1188         int ret;
1189
1190         if (dev->desc[pin])
1191                 return -EINVAL;
1192
1193         dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1194                                                    "HID/I2C:Event");
1195         if (IS_ERR(dev->desc[pin])) {
1196                 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1197                 return PTR_ERR(dev->desc[pin]);
1198         }
1199
1200         ret = gpiochip_lock_as_irq(&dev->gc, pin);
1201         if (ret) {
1202                 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1203                 goto err_desc;
1204         }
1205
1206         ret = gpiod_to_irq(dev->desc[pin]);
1207         if (ret < 0) {
1208                 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1209                 goto err_lock;
1210         }
1211
1212         return ret;
1213
1214 err_lock:
1215         gpiochip_unlock_as_irq(&dev->gc, pin);
1216 err_desc:
1217         gpiochip_free_own_desc(dev->desc[pin]);
1218         dev->desc[pin] = NULL;
1219         return ret;
1220 }
1221
1222 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1223 {
1224         struct cp2112_device *dev;
1225         u8 buf[3];
1226         struct cp2112_smbus_config_report config;
1227         int ret;
1228
1229         dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1230         if (!dev)
1231                 return -ENOMEM;
1232
1233         dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1234                                           GFP_KERNEL);
1235         if (!dev->in_out_buffer)
1236                 return -ENOMEM;
1237
1238         spin_lock_init(&dev->lock);
1239
1240         ret = hid_parse(hdev);
1241         if (ret) {
1242                 hid_err(hdev, "parse failed\n");
1243                 return ret;
1244         }
1245
1246         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1247         if (ret) {
1248                 hid_err(hdev, "hw start failed\n");
1249                 return ret;
1250         }
1251
1252         ret = hid_hw_open(hdev);
1253         if (ret) {
1254                 hid_err(hdev, "hw open failed\n");
1255                 goto err_hid_stop;
1256         }
1257
1258         ret = hid_hw_power(hdev, PM_HINT_FULLON);
1259         if (ret < 0) {
1260                 hid_err(hdev, "power management error: %d\n", ret);
1261                 goto err_hid_close;
1262         }
1263
1264         ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1265                              HID_FEATURE_REPORT);
1266         if (ret != sizeof(buf)) {
1267                 hid_err(hdev, "error requesting version\n");
1268                 if (ret >= 0)
1269                         ret = -EIO;
1270                 goto err_power_normal;
1271         }
1272
1273         hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1274                  buf[1], buf[2]);
1275
1276         ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1277                              sizeof(config), HID_FEATURE_REPORT);
1278         if (ret != sizeof(config)) {
1279                 hid_err(hdev, "error requesting SMBus config\n");
1280                 if (ret >= 0)
1281                         ret = -EIO;
1282                 goto err_power_normal;
1283         }
1284
1285         config.retry_time = cpu_to_be16(1);
1286
1287         ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1288                                 HID_FEATURE_REPORT);
1289         if (ret != sizeof(config)) {
1290                 hid_err(hdev, "error setting SMBus config\n");
1291                 if (ret >= 0)
1292                         ret = -EIO;
1293                 goto err_power_normal;
1294         }
1295
1296         hid_set_drvdata(hdev, (void *)dev);
1297         dev->hdev               = hdev;
1298         dev->adap.owner         = THIS_MODULE;
1299         dev->adap.class         = I2C_CLASS_HWMON;
1300         dev->adap.algo          = &smbus_algorithm;
1301         dev->adap.algo_data     = dev;
1302         dev->adap.dev.parent    = &hdev->dev;
1303         snprintf(dev->adap.name, sizeof(dev->adap.name),
1304                  "CP2112 SMBus Bridge on hiddev%d", hdev->minor);
1305         dev->hwversion = buf[2];
1306         init_waitqueue_head(&dev->wait);
1307
1308         hid_device_io_start(hdev);
1309         ret = i2c_add_adapter(&dev->adap);
1310         hid_device_io_stop(hdev);
1311
1312         if (ret) {
1313                 hid_err(hdev, "error registering i2c adapter\n");
1314                 goto err_power_normal;
1315         }
1316
1317         hid_dbg(hdev, "adapter registered\n");
1318
1319         dev->gc.label                   = "cp2112_gpio";
1320         dev->gc.direction_input         = cp2112_gpio_direction_input;
1321         dev->gc.direction_output        = cp2112_gpio_direction_output;
1322         dev->gc.set                     = cp2112_gpio_set;
1323         dev->gc.get                     = cp2112_gpio_get;
1324         dev->gc.base                    = -1;
1325         dev->gc.ngpio                   = 8;
1326         dev->gc.can_sleep               = 1;
1327         dev->gc.parent                  = &hdev->dev;
1328
1329         ret = gpiochip_add_data(&dev->gc, dev);
1330         if (ret < 0) {
1331                 hid_err(hdev, "error registering gpio chip\n");
1332                 goto err_free_i2c;
1333         }
1334
1335         ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1336         if (ret < 0) {
1337                 hid_err(hdev, "error creating sysfs attrs\n");
1338                 goto err_gpiochip_remove;
1339         }
1340
1341         chmod_sysfs_attrs(hdev);
1342         hid_hw_power(hdev, PM_HINT_NORMAL);
1343
1344         ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1345                                    handle_simple_irq, IRQ_TYPE_NONE);
1346         if (ret) {
1347                 dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1348                 goto err_sysfs_remove;
1349         }
1350
1351         return ret;
1352
1353 err_sysfs_remove:
1354         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1355 err_gpiochip_remove:
1356         gpiochip_remove(&dev->gc);
1357 err_free_i2c:
1358         i2c_del_adapter(&dev->adap);
1359 err_power_normal:
1360         hid_hw_power(hdev, PM_HINT_NORMAL);
1361 err_hid_close:
1362         hid_hw_close(hdev);
1363 err_hid_stop:
1364         hid_hw_stop(hdev);
1365         return ret;
1366 }
1367
1368 static void cp2112_remove(struct hid_device *hdev)
1369 {
1370         struct cp2112_device *dev = hid_get_drvdata(hdev);
1371         int i;
1372
1373         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1374         i2c_del_adapter(&dev->adap);
1375
1376         if (dev->gpio_poll) {
1377                 dev->gpio_poll = false;
1378                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1379         }
1380
1381         for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1382                 gpiochip_unlock_as_irq(&dev->gc, i);
1383                 gpiochip_free_own_desc(dev->desc[i]);
1384         }
1385
1386         gpiochip_remove(&dev->gc);
1387         /* i2c_del_adapter has finished removing all i2c devices from our
1388          * adapter. Well behaved devices should no longer call our cp2112_xfer
1389          * and should have waited for any pending calls to finish. It has also
1390          * waited for device_unregister(&adap->dev) to complete. Therefore we
1391          * can safely free our struct cp2112_device.
1392          */
1393         hid_hw_close(hdev);
1394         hid_hw_stop(hdev);
1395 }
1396
1397 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1398                             u8 *data, int size)
1399 {
1400         struct cp2112_device *dev = hid_get_drvdata(hdev);
1401         struct cp2112_xfer_status_report *xfer = (void *)data;
1402
1403         switch (data[0]) {
1404         case CP2112_TRANSFER_STATUS_RESPONSE:
1405                 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1406                         xfer->status0, xfer->status1,
1407                         be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1408
1409                 switch (xfer->status0) {
1410                 case STATUS0_IDLE:
1411                         dev->xfer_status = -EAGAIN;
1412                         break;
1413                 case STATUS0_BUSY:
1414                         dev->xfer_status = -EBUSY;
1415                         break;
1416                 case STATUS0_COMPLETE:
1417                         dev->xfer_status = be16_to_cpu(xfer->length);
1418                         break;
1419                 case STATUS0_ERROR:
1420                         switch (xfer->status1) {
1421                         case STATUS1_TIMEOUT_NACK:
1422                         case STATUS1_TIMEOUT_BUS:
1423                                 dev->xfer_status = -ETIMEDOUT;
1424                                 break;
1425                         default:
1426                                 dev->xfer_status = -EIO;
1427                                 break;
1428                         }
1429                         break;
1430                 default:
1431                         dev->xfer_status = -EINVAL;
1432                         break;
1433                 }
1434
1435                 atomic_set(&dev->xfer_avail, 1);
1436                 break;
1437         case CP2112_DATA_READ_RESPONSE:
1438                 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1439
1440                 dev->read_length = data[2];
1441                 if (dev->read_length > sizeof(dev->read_data))
1442                         dev->read_length = sizeof(dev->read_data);
1443
1444                 memcpy(dev->read_data, &data[3], dev->read_length);
1445                 atomic_set(&dev->read_avail, 1);
1446                 break;
1447         default:
1448                 hid_err(hdev, "unknown report\n");
1449
1450                 return 0;
1451         }
1452
1453         wake_up_interruptible(&dev->wait);
1454         return 1;
1455 }
1456
1457 static struct hid_driver cp2112_driver = {
1458         .name           = "cp2112",
1459         .id_table       = cp2112_devices,
1460         .probe          = cp2112_probe,
1461         .remove         = cp2112_remove,
1462         .raw_event      = cp2112_raw_event,
1463 };
1464
1465 module_hid_driver(cp2112_driver);
1466 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1467 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1468 MODULE_LICENSE("GPL");
1469