drivers/input/touchscreen/goodix.c

   1 /*
   2  *  Driver for Goodix Touchscreens
   3  *
   4  *  Copyright (c) 2014 Red Hat Inc.
   5  *
   6  *  This code is based on gt9xx.c authored by andrew@goodix.com:
   7  *
   8  *  2010 - 2012 Goodix Technology.
   9  */
  10
  11 /*
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the Free
  14  * Software Foundation; version 2 of the License.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/i2c.h>
  19 #include <linux/input.h>
  20 #include <linux/input/mt.h>
  21 #include <linux/module.h>
  22 #include <linux/delay.h>
  23 #include <linux/irq.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/slab.h>
  26 #include <linux/acpi.h>
  27 #include <linux/of.h>
  28 #include <asm/unaligned.h>
  29
  30 struct goodix_ts_data {
  31         struct i2c_client *client;
  32         struct input_dev *input_dev;
  33         int abs_x_max;
  34         int abs_y_max;
  35         unsigned int max_touch_num;
  36         unsigned int int_trigger_type;
  37 };
  38
  39 #define GOODIX_MAX_HEIGHT               4096
  40 #define GOODIX_MAX_WIDTH                4096
  41 #define GOODIX_INT_TRIGGER              1
  42 #define GOODIX_CONTACT_SIZE             8
  43 #define GOODIX_MAX_CONTACTS             10
  44
  45 #define GOODIX_CONFIG_MAX_LENGTH        240
  46
  47 /* Register defines */
  48 #define GOODIX_READ_COOR_ADDR           0x814E
  49 #define GOODIX_REG_CONFIG_DATA          0x8047
  50 #define GOODIX_REG_VERSION              0x8140
  51
  52 #define RESOLUTION_LOC          1
  53 #define MAX_CONTACTS_LOC        5
  54 #define TRIGGER_LOC             6
  55
  56 static const unsigned long goodix_irq_flags[] = {
  57         IRQ_TYPE_EDGE_RISING,
  58         IRQ_TYPE_EDGE_FALLING,
  59         IRQ_TYPE_LEVEL_LOW,
  60         IRQ_TYPE_LEVEL_HIGH,
  61 };
  62
  63 /**
  64  * goodix_i2c_read - read data from a register of the i2c slave device.
  65  *
  66  * @client: i2c device.
  67  * @reg: the register to read from.
  68  * @buf: raw write data buffer.
  69  * @len: length of the buffer to write
  70  */
  71 static int goodix_i2c_read(struct i2c_client *client,
  72                            u16 reg, u8 *buf, int len)
  73 {
  74         struct i2c_msg msgs[2];
  75         u16 wbuf = cpu_to_be16(reg);
  76         int ret;
  77
  78         msgs[0].flags = 0;
  79         msgs[0].addr  = client->addr;
  80         msgs[0].len   = 2;
  81         msgs[0].buf   = (u8 *)&wbuf;
  82
  83         msgs[1].flags = I2C_M_RD;
  84         msgs[1].addr  = client->addr;
  85         msgs[1].len   = len;
  86         msgs[1].buf   = buf;
  87
  88         ret = i2c_transfer(client->adapter, msgs, 2);
  89         return ret < 0 ? ret : (ret != ARRAY_SIZE(msgs) ? -EIO : 0);
  90 }
  91
  92 static int goodix_ts_read_input_report(struct goodix_ts_data *ts, u8 *data)
  93 {
  94         int touch_num;
  95         int error;
  96
  97         error = goodix_i2c_read(ts->client, GOODIX_READ_COOR_ADDR, data,
  98                                 GOODIX_CONTACT_SIZE + 1);
  99         if (error) {
 100                 dev_err(&ts->client->dev, "I2C transfer error: %d\n", error);
 101                 return error;
 102         }
 103
 104         if (!(data[0] & 0x80))
 105                 return -EAGAIN;
 106
 107         touch_num = data[0] & 0x0f;
 108         if (touch_num > ts->max_touch_num)
 109                 return -EPROTO;
 110
 111         if (touch_num > 1) {
 112                 data += 1 + GOODIX_CONTACT_SIZE;
 113                 error = goodix_i2c_read(ts->client,
 114                                         GOODIX_READ_COOR_ADDR +
 115                                                 1 + GOODIX_CONTACT_SIZE,
 116                                         data,
 117                                         GOODIX_CONTACT_SIZE * (touch_num - 1));
 118                 if (error)
 119                         return error;
 120         }
 121
 122         return touch_num;
 123 }
 124
 125 static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
 126 {
 127         int id = coor_data[0] & 0x0F;
 128         int input_x = get_unaligned_le16(&coor_data[1]);
 129         int input_y = get_unaligned_le16(&coor_data[3]);
 130         int input_w = get_unaligned_le16(&coor_data[5]);
 131
 132         input_mt_slot(ts->input_dev, id);
 133         input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
 134         input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
 135         input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
 136         input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
 137         input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
 138 }
 139
 140 /**
 141  * goodix_process_events - Process incoming events
 142  *
 143  * @ts: our goodix_ts_data pointer
 144  *
 145  * Called when the IRQ is triggered. Read the current device state, and push
 146  * the input events to the user space.
 147  */
 148 static void goodix_process_events(struct goodix_ts_data *ts)
 149 {
 150         u8  point_data[1 + GOODIX_CONTACT_SIZE * ts->max_touch_num];
 151         int touch_num;
 152         int i;
 153
 154         touch_num = goodix_ts_read_input_report(ts, point_data);
 155         if (touch_num < 0)
 156                 return;
 157
 158         for (i = 0; i < touch_num; i++)
 159                 goodix_ts_report_touch(ts,
 160                                 &point_data[1 + GOODIX_CONTACT_SIZE * i]);
 161
 162         input_mt_sync_frame(ts->input_dev);
 163         input_sync(ts->input_dev);
 164 }
 165
 166 /**
 167  * goodix_ts_irq_handler - The IRQ handler
 168  *
 169  * @irq: interrupt number.
 170  * @dev_id: private data pointer.
 171  */
 172 static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
 173 {
 174         static const u8 end_cmd[] = {
 175                 GOODIX_READ_COOR_ADDR >> 8,
 176                 GOODIX_READ_COOR_ADDR & 0xff,
 177                 0
 178         };
 179         struct goodix_ts_data *ts = dev_id;
 180
 181         goodix_process_events(ts);
 182
 183         if (i2c_master_send(ts->client, end_cmd, sizeof(end_cmd)) < 0)
 184                 dev_err(&ts->client->dev, "I2C write end_cmd error\n");
 185
 186         return IRQ_HANDLED;
 187 }
 188
 189 /**
 190  * goodix_read_config - Read the embedded configuration of the panel
 191  *
 192  * @ts: our goodix_ts_data pointer
 193  *
 194  * Must be called during probe
 195  */
 196 static void goodix_read_config(struct goodix_ts_data *ts)
 197 {
 198         u8 config[GOODIX_CONFIG_MAX_LENGTH];
 199         int error;
 200
 201         error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA,
 202                                 config,
 203                                 GOODIX_CONFIG_MAX_LENGTH);
 204         if (error) {
 205                 dev_warn(&ts->client->dev,
 206                          "Error reading config (%d), using defaults\n",
 207                          error);
 208                 ts->abs_x_max = GOODIX_MAX_WIDTH;
 209                 ts->abs_y_max = GOODIX_MAX_HEIGHT;
 210                 ts->int_trigger_type = GOODIX_INT_TRIGGER;
 211                 ts->max_touch_num = GOODIX_MAX_CONTACTS;
 212                 return;
 213         }
 214
 215         ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
 216         ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
 217         ts->int_trigger_type = config[TRIGGER_LOC] & 0x03;
 218         ts->max_touch_num = config[MAX_CONTACTS_LOC] & 0x0f;
 219         if (!ts->abs_x_max || !ts->abs_y_max || !ts->max_touch_num) {
 220                 dev_err(&ts->client->dev,
 221                         "Invalid config, using defaults\n");
 222                 ts->abs_x_max = GOODIX_MAX_WIDTH;
 223                 ts->abs_y_max = GOODIX_MAX_HEIGHT;
 224                 ts->max_touch_num = GOODIX_MAX_CONTACTS;
 225         }
 226 }
 227
 228 /**
 229  * goodix_read_version - Read goodix touchscreen version
 230  *
 231  * @client: the i2c client
 232  * @version: output buffer containing the version on success
 233  */
 234 static int goodix_read_version(struct i2c_client *client, u16 *version)
 235 {
 236         int error;
 237         u8 buf[6];
 238
 239         error = goodix_i2c_read(client, GOODIX_REG_VERSION, buf, sizeof(buf));
 240         if (error) {
 241                 dev_err(&client->dev, "read version failed: %d\n", error);
 242                 return error;
 243         }
 244
 245         if (version)
 246                 *version = get_unaligned_le16(&buf[4]);
 247
 248         dev_info(&client->dev, "IC VERSION: %6ph\n", buf);
 249
 250         return 0;
 251 }
 252
 253 /**
 254  * goodix_i2c_test - I2C test function to check if the device answers.
 255  *
 256  * @client: the i2c client
 257  */
 258 static int goodix_i2c_test(struct i2c_client *client)
 259 {
 260         int retry = 0;
 261         int error;
 262         u8 test;
 263
 264         while (retry++ < 2) {
 265                 error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
 266                                         &test, 1);
 267                 if (!error)
 268                         return 0;
 269
 270                 dev_err(&client->dev, "i2c test failed attempt %d: %d\n",
 271                         retry, error);
 272                 msleep(20);
 273         }
 274
 275         return error;
 276 }
 277
 278 /**
 279  * goodix_request_input_dev - Allocate, populate and register the input device
 280  *
 281  * @ts: our goodix_ts_data pointer
 282  *
 283  * Must be called during probe
 284  */
 285 static int goodix_request_input_dev(struct goodix_ts_data *ts)
 286 {
 287         int error;
 288
 289         ts->input_dev = devm_input_allocate_device(&ts->client->dev);
 290         if (!ts->input_dev) {
 291                 dev_err(&ts->client->dev, "Failed to allocate input device.");
 292                 return -ENOMEM;
 293         }
 294
 295         ts->input_dev->evbit[0] = BIT_MASK(EV_SYN) |
 296                                   BIT_MASK(EV_KEY) |
 297                                   BIT_MASK(EV_ABS);
 298
 299         input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X,
 300                              0, ts->abs_x_max, 0, 0);
 301         input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y,
 302                              0, ts->abs_y_max, 0, 0);
 303         input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
 304         input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
 305
 306         input_mt_init_slots(ts->input_dev, ts->max_touch_num,
 307                             INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
 308
 309         ts->input_dev->name = "Goodix Capacitive TouchScreen";
 310         ts->input_dev->phys = "input/ts";
 311         ts->input_dev->id.bustype = BUS_I2C;
 312         ts->input_dev->id.vendor = 0x0416;
 313         ts->input_dev->id.product = 0x1001;
 314         ts->input_dev->id.version = 10427;
 315
 316         error = input_register_device(ts->input_dev);
 317         if (error) {
 318                 dev_err(&ts->client->dev,
 319                         "Failed to register input device: %d", error);
 320                 return error;
 321         }
 322
 323         return 0;
 324 }
 325
 326 static int goodix_ts_probe(struct i2c_client *client,
 327                            const struct i2c_device_id *id)
 328 {
 329         struct goodix_ts_data *ts;
 330         unsigned long irq_flags;
 331         int error;
 332         u16 version_info;
 333
 334         dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
 335
 336         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 337                 dev_err(&client->dev, "I2C check functionality failed.\n");
 338                 return -ENXIO;
 339         }
 340
 341         ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
 342         if (!ts)
 343                 return -ENOMEM;
 344
 345         ts->client = client;
 346         i2c_set_clientdata(client, ts);
 347
 348         error = goodix_i2c_test(client);
 349         if (error) {
 350                 dev_err(&client->dev, "I2C communication failure: %d\n", error);
 351                 return error;
 352         }
 353
 354         error = goodix_read_version(client, &version_info);
 355         if (error) {
 356                 dev_err(&client->dev, "Read version failed.\n");
 357                 return error;
 358         }
 359
 360         goodix_read_config(ts);
 361
 362         error = goodix_request_input_dev(ts);
 363         if (error)
 364                 return error;
 365
 366         irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
 367         error = devm_request_threaded_irq(&ts->client->dev, client->irq,
 368                                           NULL, goodix_ts_irq_handler,
 369                                           irq_flags, client->name, ts);
 370         if (error) {
 371                 dev_err(&client->dev, "request IRQ failed: %d\n", error);
 372                 return error;
 373         }
 374
 375         return 0;
 376 }
 377
 378 static const struct i2c_device_id goodix_ts_id[] = {
 379         { "GDIX1001:00", 0 },
 380         { }
 381 };
 382
 383 #ifdef CONFIG_ACPI
 384 static const struct acpi_device_id goodix_acpi_match[] = {
 385         { "GDIX1001", 0 },
 386         { }
 387 };
 388 MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
 389 #endif
 390
 391 #ifdef CONFIG_OF
 392 static const struct of_device_id goodix_of_match[] = {
 393         { .compatible = "goodix,gt911" },
 394         { .compatible = "goodix,gt9110" },
 395         { .compatible = "goodix,gt912" },
 396         { .compatible = "goodix,gt927" },
 397         { .compatible = "goodix,gt9271" },
 398         { .compatible = "goodix,gt928" },
 399         { .compatible = "goodix,gt967" },
 400         { }
 401 };
 402 MODULE_DEVICE_TABLE(of, goodix_of_match);
 403 #endif
 404
 405 static struct i2c_driver goodix_ts_driver = {
 406         .probe = goodix_ts_probe,
 407         .id_table = goodix_ts_id,
 408         .driver = {
 409                 .name = "Goodix-TS",
 410                 .owner = THIS_MODULE,
 411                 .acpi_match_table = ACPI_PTR(goodix_acpi_match),
 412                 .of_match_table = of_match_ptr(goodix_of_match),
 413         },
 414 };
 415 module_i2c_driver(goodix_ts_driver);
 416
 417 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
 418 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
 419 MODULE_DESCRIPTION("Goodix touchscreen driver");
 420 MODULE_LICENSE("GPL v2");