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_ID                   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 * GOODIX_MAX_CONTACTS];
 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  * @id: output buffer containing the id on success
 234  */
 235 static int goodix_read_version(struct i2c_client *client, u16 *version, u16 *id)
 236 {
 237         int error;
 238         u8 buf[6];
 239         char id_str[5];
 240
 241         error = goodix_i2c_read(client, GOODIX_REG_ID, buf, sizeof(buf));
 242         if (error) {
 243                 dev_err(&client->dev, "read version failed: %d\n", error);
 244                 return error;
 245         }
 246
 247         memcpy(id_str, buf, 4);
 248         id_str[4] = 0;
 249         if (kstrtou16(id_str, 10, id))
 250                 *id = 0x1001;
 251
 252         *version = get_unaligned_le16(&buf[4]);
 253
 254         dev_info(&client->dev, "ID %d, version: %04x\n", *id, *version);
 255
 256         return 0;
 257 }
 258
 259 /**
 260  * goodix_i2c_test - I2C test function to check if the device answers.
 261  *
 262  * @client: the i2c client
 263  */
 264 static int goodix_i2c_test(struct i2c_client *client)
 265 {
 266         int retry = 0;
 267         int error;
 268         u8 test;
 269
 270         while (retry++ < 2) {
 271                 error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
 272                                         &test, 1);
 273                 if (!error)
 274                         return 0;
 275
 276                 dev_err(&client->dev, "i2c test failed attempt %d: %d\n",
 277                         retry, error);
 278                 msleep(20);
 279         }
 280
 281         return error;
 282 }
 283
 284 /**
 285  * goodix_request_input_dev - Allocate, populate and register the input device
 286  *
 287  * @ts: our goodix_ts_data pointer
 288  * @version: device firmware version
 289  * @id: device ID
 290  *
 291  * Must be called during probe
 292  */
 293 static int goodix_request_input_dev(struct goodix_ts_data *ts, u16 version,
 294                                     u16 id)
 295 {
 296         int error;
 297
 298         ts->input_dev = devm_input_allocate_device(&ts->client->dev);
 299         if (!ts->input_dev) {
 300                 dev_err(&ts->client->dev, "Failed to allocate input device.");
 301                 return -ENOMEM;
 302         }
 303
 304         input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X,
 305                              0, ts->abs_x_max, 0, 0);
 306         input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y,
 307                              0, ts->abs_y_max, 0, 0);
 308         input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
 309         input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
 310
 311         input_mt_init_slots(ts->input_dev, ts->max_touch_num,
 312                             INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
 313
 314         ts->input_dev->name = "Goodix Capacitive TouchScreen";
 315         ts->input_dev->phys = "input/ts";
 316         ts->input_dev->id.bustype = BUS_I2C;
 317         ts->input_dev->id.vendor = 0x0416;
 318         ts->input_dev->id.product = id;
 319         ts->input_dev->id.version = version;
 320
 321         error = input_register_device(ts->input_dev);
 322         if (error) {
 323                 dev_err(&ts->client->dev,
 324                         "Failed to register input device: %d", error);
 325                 return error;
 326         }
 327
 328         return 0;
 329 }
 330
 331 static int goodix_ts_probe(struct i2c_client *client,
 332                            const struct i2c_device_id *id)
 333 {
 334         struct goodix_ts_data *ts;
 335         unsigned long irq_flags;
 336         int error;
 337         u16 version_info, id_info;
 338
 339         dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
 340
 341         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 342                 dev_err(&client->dev, "I2C check functionality failed.\n");
 343                 return -ENXIO;
 344         }
 345
 346         ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
 347         if (!ts)
 348                 return -ENOMEM;
 349
 350         ts->client = client;
 351         i2c_set_clientdata(client, ts);
 352
 353         error = goodix_i2c_test(client);
 354         if (error) {
 355                 dev_err(&client->dev, "I2C communication failure: %d\n", error);
 356                 return error;
 357         }
 358
 359         error = goodix_read_version(client, &version_info, &id_info);
 360         if (error) {
 361                 dev_err(&client->dev, "Read version failed.\n");
 362                 return error;
 363         }
 364
 365         goodix_read_config(ts);
 366
 367         error = goodix_request_input_dev(ts, version_info, id_info);
 368         if (error)
 369                 return error;
 370
 371         irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
 372         error = devm_request_threaded_irq(&ts->client->dev, client->irq,
 373                                           NULL, goodix_ts_irq_handler,
 374                                           irq_flags, client->name, ts);
 375         if (error) {
 376                 dev_err(&client->dev, "request IRQ failed: %d\n", error);
 377                 return error;
 378         }
 379
 380         return 0;
 381 }
 382
 383 static const struct i2c_device_id goodix_ts_id[] = {
 384         { "GDIX1001:00", 0 },
 385         { }
 386 };
 387
 388 #ifdef CONFIG_ACPI
 389 static const struct acpi_device_id goodix_acpi_match[] = {
 390         { "GDIX1001", 0 },
 391         { }
 392 };
 393 MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
 394 #endif
 395
 396 #ifdef CONFIG_OF
 397 static const struct of_device_id goodix_of_match[] = {
 398         { .compatible = "goodix,gt911" },
 399         { .compatible = "goodix,gt9110" },
 400         { .compatible = "goodix,gt912" },
 401         { .compatible = "goodix,gt927" },
 402         { .compatible = "goodix,gt9271" },
 403         { .compatible = "goodix,gt928" },
 404         { .compatible = "goodix,gt967" },
 405         { }
 406 };
 407 MODULE_DEVICE_TABLE(of, goodix_of_match);
 408 #endif
 409
 410 static struct i2c_driver goodix_ts_driver = {
 411         .probe = goodix_ts_probe,
 412         .id_table = goodix_ts_id,
 413         .driver = {
 414                 .name = "Goodix-TS",
 415                 .owner = THIS_MODULE,
 416                 .acpi_match_table = ACPI_PTR(goodix_acpi_match),
 417                 .of_match_table = of_match_ptr(goodix_of_match),
 418         },
 419 };
 420 module_i2c_driver(goodix_ts_driver);
 421
 422 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
 423 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
 424 MODULE_DESCRIPTION("Goodix touchscreen driver");
 425 MODULE_LICENSE("GPL v2");