kernel/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         touch_num = data[0] & 0x0f;
 105         if (touch_num > ts->max_touch_num)
 106                 return -EPROTO;
 107
 108         if (touch_num > 1) {
 109                 data += 1 + GOODIX_CONTACT_SIZE;
 110                 error = goodix_i2c_read(ts->client,
 111                                         GOODIX_READ_COOR_ADDR +
 112                                                 1 + GOODIX_CONTACT_SIZE,
 113                                         data,
 114                                         GOODIX_CONTACT_SIZE * (touch_num - 1));
 115                 if (error)
 116                         return error;
 117         }
 118
 119         return touch_num;
 120 }
 121
 122 static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
 123 {
 124         int id = coor_data[0] & 0x0F;
 125         int input_x = get_unaligned_le16(&coor_data[1]);
 126         int input_y = get_unaligned_le16(&coor_data[3]);
 127         int input_w = get_unaligned_le16(&coor_data[5]);
 128
 129         input_mt_slot(ts->input_dev, id);
 130         input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
 131         input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
 132         input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
 133         input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
 134         input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
 135 }
 136
 137 /**
 138  * goodix_process_events - Process incoming events
 139  *
 140  * @ts: our goodix_ts_data pointer
 141  *
 142  * Called when the IRQ is triggered. Read the current device state, and push
 143  * the input events to the user space.
 144  */
 145 static void goodix_process_events(struct goodix_ts_data *ts)
 146 {
 147         u8  point_data[1 + GOODIX_CONTACT_SIZE * ts->max_touch_num];
 148         int touch_num;
 149         int i;
 150
 151         touch_num = goodix_ts_read_input_report(ts, point_data);
 152         if (touch_num < 0)
 153                 return;
 154
 155         for (i = 0; i < touch_num; i++)
 156                 goodix_ts_report_touch(ts,
 157                                 &point_data[1 + GOODIX_CONTACT_SIZE * i]);
 158
 159         input_mt_sync_frame(ts->input_dev);
 160         input_sync(ts->input_dev);
 161 }
 162
 163 /**
 164  * goodix_ts_irq_handler - The IRQ handler
 165  *
 166  * @irq: interrupt number.
 167  * @dev_id: private data pointer.
 168  */
 169 static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
 170 {
 171         static const u8 end_cmd[] = {
 172                 GOODIX_READ_COOR_ADDR >> 8,
 173                 GOODIX_READ_COOR_ADDR & 0xff,
 174                 0
 175         };
 176         struct goodix_ts_data *ts = dev_id;
 177
 178         goodix_process_events(ts);
 179
 180         if (i2c_master_send(ts->client, end_cmd, sizeof(end_cmd)) < 0)
 181                 dev_err(&ts->client->dev, "I2C write end_cmd error\n");
 182
 183         return IRQ_HANDLED;
 184 }
 185
 186 /**
 187  * goodix_read_config - Read the embedded configuration of the panel
 188  *
 189  * @ts: our goodix_ts_data pointer
 190  *
 191  * Must be called during probe
 192  */
 193 static void goodix_read_config(struct goodix_ts_data *ts)
 194 {
 195         u8 config[GOODIX_CONFIG_MAX_LENGTH];
 196         int error;
 197
 198         error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA,
 199                               config,
 200                            GOODIX_CONFIG_MAX_LENGTH);
 201         if (error) {
 202                 dev_warn(&ts->client->dev,
 203                          "Error reading config (%d), using defaults\n",
 204                          error);
 205                 ts->abs_x_max = GOODIX_MAX_WIDTH;
 206                 ts->abs_y_max = GOODIX_MAX_HEIGHT;
 207                 ts->int_trigger_type = GOODIX_INT_TRIGGER;
 208                 ts->max_touch_num = GOODIX_MAX_CONTACTS;
 209                 return;
 210         }
 211
 212         ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
 213         ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
 214         ts->int_trigger_type = config[TRIGGER_LOC] & 0x03;
 215         ts->max_touch_num = config[MAX_CONTACTS_LOC] & 0x0f;
 216         if (!ts->abs_x_max || !ts->abs_y_max || !ts->max_touch_num) {
 217                 dev_err(&ts->client->dev,
 218                         "Invalid config, using defaults\n");
 219                 ts->abs_x_max = GOODIX_MAX_WIDTH;
 220                 ts->abs_y_max = GOODIX_MAX_HEIGHT;
 221                 ts->max_touch_num = GOODIX_MAX_CONTACTS;
 222         }
 223 }
 224
 225 /**
 226  * goodix_read_version - Read goodix touchscreen version
 227  *
 228  * @client: the i2c client
 229  * @version: output buffer containing the version on success
 230  */
 231 static int goodix_read_version(struct i2c_client *client, u16 *version)
 232 {
 233         int error;
 234         u8 buf[6];
 235
 236         error = goodix_i2c_read(client, GOODIX_REG_VERSION, buf, sizeof(buf));
 237         if (error) {
 238                 dev_err(&client->dev, "read version failed: %d\n", error);
 239                 return error;
 240         }
 241
 242         if (version)
 243                 *version = get_unaligned_le16(&buf[4]);
 244
 245         dev_info(&client->dev, "IC VERSION: %6ph\n", buf);
 246
 247         return 0;
 248 }
 249
 250 /**
 251  * goodix_i2c_test - I2C test function to check if the device answers.
 252  *
 253  * @client: the i2c client
 254  */
 255 static int goodix_i2c_test(struct i2c_client *client)
 256 {
 257         int retry = 0;
 258         int error;
 259         u8 test;
 260
 261         while (retry++ < 2) {
 262                 error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
 263                                         &test, 1);
 264                 if (!error)
 265                         return 0;
 266
 267                 dev_err(&client->dev, "i2c test failed attempt %d: %d\n",
 268                         retry, error);
 269                 msleep(20);
 270         }
 271
 272         return error;
 273 }
 274
 275 /**
 276  * goodix_request_input_dev - Allocate, populate and register the input device
 277  *
 278  * @ts: our goodix_ts_data pointer
 279  *
 280  * Must be called during probe
 281  */
 282 static int goodix_request_input_dev(struct goodix_ts_data *ts)
 283 {
 284         int error;
 285
 286         ts->input_dev = devm_input_allocate_device(&ts->client->dev);
 287         if (!ts->input_dev) {
 288                 dev_err(&ts->client->dev, "Failed to allocate input device.");
 289                 return -ENOMEM;
 290         }
 291
 292         ts->input_dev->evbit[0] = BIT_MASK(EV_SYN) |
 293                                   BIT_MASK(EV_KEY) |
 294                                   BIT_MASK(EV_ABS);
 295
 296         input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X, 0,
 297                                 ts->abs_x_max, 0, 0);
 298         input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y, 0,
 299                                 ts->abs_y_max, 0, 0);
 300         input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
 301         input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
 302
 303         input_mt_init_slots(ts->input_dev, ts->max_touch_num,
 304                             INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
 305
 306         ts->input_dev->name = "Goodix Capacitive TouchScreen";
 307         ts->input_dev->phys = "input/ts";
 308         ts->input_dev->id.bustype = BUS_I2C;
 309         ts->input_dev->id.vendor = 0x0416;
 310         ts->input_dev->id.product = 0x1001;
 311         ts->input_dev->id.version = 10427;
 312
 313         error = input_register_device(ts->input_dev);
 314         if (error) {
 315                 dev_err(&ts->client->dev,
 316                         "Failed to register input device: %d", error);
 317                 return error;
 318         }
 319
 320         return 0;
 321 }
 322
 323 static int goodix_ts_probe(struct i2c_client *client,
 324                            const struct i2c_device_id *id)
 325 {
 326         struct goodix_ts_data *ts;
 327         unsigned long irq_flags;
 328         int error;
 329         u16 version_info;
 330
 331         dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
 332
 333         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 334                 dev_err(&client->dev, "I2C check functionality failed.\n");
 335                 return -ENXIO;
 336         }
 337
 338         ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
 339         if (!ts)
 340                 return -ENOMEM;
 341
 342         ts->client = client;
 343         i2c_set_clientdata(client, ts);
 344
 345         error = goodix_i2c_test(client);
 346         if (error) {
 347                 dev_err(&client->dev, "I2C communication failure: %d\n", error);
 348                 return error;
 349         }
 350
 351         error = goodix_read_version(client, &version_info);
 352         if (error) {
 353                 dev_err(&client->dev, "Read version failed.\n");
 354                 return error;
 355         }
 356
 357         goodix_read_config(ts);
 358
 359         error = goodix_request_input_dev(ts);
 360         if (error)
 361                 return error;
 362
 363         irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
 364         error = devm_request_threaded_irq(&ts->client->dev, client->irq,
 365                                           NULL, goodix_ts_irq_handler,
 366                                           irq_flags, client->name, ts);
 367         if (error) {
 368                 dev_err(&client->dev, "request IRQ failed: %d\n", error);
 369                 return error;
 370         }
 371
 372         return 0;
 373 }
 374
 375 static const struct i2c_device_id goodix_ts_id[] = {
 376         { "GDIX1001:00", 0 },
 377         { }
 378 };
 379
 380 #ifdef CONFIG_ACPI
 381 static const struct acpi_device_id goodix_acpi_match[] = {
 382         { "GDIX1001", 0 },
 383         { }
 384 };
 385 MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
 386 #endif
 387
 388 #ifdef CONFIG_OF
 389 static const struct of_device_id goodix_of_match[] = {
 390         { .compatible = "goodix,gt911" },
 391         { .compatible = "goodix,gt9110" },
 392         { .compatible = "goodix,gt912" },
 393         { .compatible = "goodix,gt927" },
 394         { .compatible = "goodix,gt9271" },
 395         { .compatible = "goodix,gt928" },
 396         { .compatible = "goodix,gt967" },
 397         { }
 398 };
 399 MODULE_DEVICE_TABLE(of, goodix_of_match);
 400 #endif
 401
 402 static struct i2c_driver goodix_ts_driver = {
 403         .probe = goodix_ts_probe,
 404         .id_table = goodix_ts_id,
 405         .driver = {
 406                 .name = "Goodix-TS",
 407                 .owner = THIS_MODULE,
 408                 .acpi_match_table = ACPI_PTR(goodix_acpi_match),
 409                 .of_match_table = of_match_ptr(goodix_of_match),
 410         },
 411 };
 412 module_i2c_driver(goodix_ts_driver);
 413
 414 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
 415 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
 416 MODULE_DESCRIPTION("Goodix touchscreen driver");
 417 MODULE_LICENSE("GPL v2");