drivers/input/touchscreen/edt-ft5x06.c

   1 /*
   2  * Copyright (C) 2012 Simon Budig, <simon.budig@kernelconcepts.de>
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16  */
  17
  18 /*
  19  * This is a driver for the EDT "Polytouch" family of touch controllers
  20  * based on the FocalTech FT5x06 line of chips.
  21  *
  22  * Development of this driver has been sponsored by Glyn:
  23  *    http://www.glyn.com/Products/Displays
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/ratelimit.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/input.h>
  30 #include <linux/i2c.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/delay.h>
  33 #include <linux/debugfs.h>
  34 #include <linux/slab.h>
  35 #include <linux/gpio.h>
  36 #include <linux/input/mt.h>
  37 #include <linux/input/edt-ft5x06.h>
  38
  39 #define MAX_SUPPORT_POINTS              5
  40
  41 #define WORK_REGISTER_THRESHOLD         0x00
  42 #define WORK_REGISTER_REPORT_RATE       0x08
  43 #define WORK_REGISTER_GAIN              0x30
  44 #define WORK_REGISTER_OFFSET            0x31
  45 #define WORK_REGISTER_NUM_X             0x33
  46 #define WORK_REGISTER_NUM_Y             0x34
  47
  48 #define WORK_REGISTER_OPMODE            0x3c
  49 #define FACTORY_REGISTER_OPMODE         0x01
  50
  51 #define TOUCH_EVENT_DOWN                0x00
  52 #define TOUCH_EVENT_UP                  0x01
  53 #define TOUCH_EVENT_ON                  0x02
  54 #define TOUCH_EVENT_RESERVED            0x03
  55
  56 #define EDT_NAME_LEN                    23
  57 #define EDT_SWITCH_MODE_RETRIES         10
  58 #define EDT_SWITCH_MODE_DELAY           5 /* msec */
  59 #define EDT_RAW_DATA_RETRIES            100
  60 #define EDT_RAW_DATA_DELAY              1 /* msec */
  61
  62 struct edt_ft5x06_ts_data {
  63         struct i2c_client *client;
  64         struct input_dev *input;
  65         u16 num_x;
  66         u16 num_y;
  67
  68 #if defined(CONFIG_DEBUG_FS)
  69         struct dentry *debug_dir;
  70         u8 *raw_buffer;
  71         size_t raw_bufsize;
  72 #endif
  73
  74         struct mutex mutex;
  75         bool factory_mode;
  76         int threshold;
  77         int gain;
  78         int offset;
  79         int report_rate;
  80
  81         char name[EDT_NAME_LEN];
  82 };
  83
  84 static int edt_ft5x06_ts_readwrite(struct i2c_client *client,
  85                                    u16 wr_len, u8 *wr_buf,
  86                                    u16 rd_len, u8 *rd_buf)
  87 {
  88         struct i2c_msg wrmsg[2];
  89         int i = 0;
  90         int ret;
  91
  92         if (wr_len) {
  93                 wrmsg[i].addr  = client->addr;
  94                 wrmsg[i].flags = 0;
  95                 wrmsg[i].len = wr_len;
  96                 wrmsg[i].buf = wr_buf;
  97                 i++;
  98         }
  99         if (rd_len) {
 100                 wrmsg[i].addr  = client->addr;
 101                 wrmsg[i].flags = I2C_M_RD;
 102                 wrmsg[i].len = rd_len;
 103                 wrmsg[i].buf = rd_buf;
 104                 i++;
 105         }
 106
 107         ret = i2c_transfer(client->adapter, wrmsg, i);
 108         if (ret < 0)
 109                 return ret;
 110         if (ret != i)
 111                 return -EIO;
 112
 113         return 0;
 114 }
 115
 116 static bool edt_ft5x06_ts_check_crc(struct edt_ft5x06_ts_data *tsdata,
 117                                     u8 *buf, int buflen)
 118 {
 119         int i;
 120         u8 crc = 0;
 121
 122         for (i = 0; i < buflen - 1; i++)
 123                 crc ^= buf[i];
 124
 125         if (crc != buf[buflen-1]) {
 126                 dev_err_ratelimited(&tsdata->client->dev,
 127                                     "crc error: 0x%02x expected, got 0x%02x\n",
 128                                     crc, buf[buflen-1]);
 129                 return false;
 130         }
 131
 132         return true;
 133 }
 134
 135 static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
 136 {
 137         struct edt_ft5x06_ts_data *tsdata = dev_id;
 138         struct device *dev = &tsdata->client->dev;
 139         u8 cmd = 0xf9;
 140         u8 rdbuf[26];
 141         int i, type, x, y, id;
 142         int error;
 143
 144         memset(rdbuf, 0, sizeof(rdbuf));
 145
 146         error = edt_ft5x06_ts_readwrite(tsdata->client,
 147                                         sizeof(cmd), &cmd,
 148                                         sizeof(rdbuf), rdbuf);
 149         if (error) {
 150                 dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n",
 151                                     error);
 152                 goto out;
 153         }
 154
 155         if (rdbuf[0] != 0xaa || rdbuf[1] != 0xaa || rdbuf[2] != 26) {
 156                 dev_err_ratelimited(dev, "Unexpected header: %02x%02x%02x!\n",
 157                                     rdbuf[0], rdbuf[1], rdbuf[2]);
 158                 goto out;
 159         }
 160
 161         if (!edt_ft5x06_ts_check_crc(tsdata, rdbuf, 26))
 162                 goto out;
 163
 164         for (i = 0; i < MAX_SUPPORT_POINTS; i++) {
 165                 u8 *buf = &rdbuf[i * 4 + 5];
 166                 bool down;
 167
 168                 type = buf[0] >> 6;
 169                 /* ignore Reserved events */
 170                 if (type == TOUCH_EVENT_RESERVED)
 171                         continue;
 172
 173                 x = ((buf[0] << 8) | buf[1]) & 0x0fff;
 174                 y = ((buf[2] << 8) | buf[3]) & 0x0fff;
 175                 id = (buf[2] >> 4) & 0x0f;
 176                 down = (type != TOUCH_EVENT_UP);
 177
 178                 input_mt_slot(tsdata->input, id);
 179                 input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER, down);
 180
 181                 if (!down)
 182                         continue;
 183
 184                 input_report_abs(tsdata->input, ABS_MT_POSITION_X, x);
 185                 input_report_abs(tsdata->input, ABS_MT_POSITION_Y, y);
 186         }
 187
 188         input_mt_report_pointer_emulation(tsdata->input, true);
 189         input_sync(tsdata->input);
 190
 191 out:
 192         return IRQ_HANDLED;
 193 }
 194
 195 static int edt_ft5x06_register_write(struct edt_ft5x06_ts_data *tsdata,
 196                                      u8 addr, u8 value)
 197 {
 198         u8 wrbuf[4];
 199
 200         wrbuf[0] = tsdata->factory_mode ? 0xf3 : 0xfc;
 201         wrbuf[1] = tsdata->factory_mode ? addr & 0x7f : addr & 0x3f;
 202         wrbuf[2] = value;
 203         wrbuf[3] = wrbuf[0] ^ wrbuf[1] ^ wrbuf[2];
 204
 205         return edt_ft5x06_ts_readwrite(tsdata->client, 4, wrbuf, 0, NULL);
 206 }
 207
 208 static int edt_ft5x06_register_read(struct edt_ft5x06_ts_data *tsdata,
 209                                     u8 addr)
 210 {
 211         u8 wrbuf[2], rdbuf[2];
 212         int error;
 213
 214         wrbuf[0] = tsdata->factory_mode ? 0xf3 : 0xfc;
 215         wrbuf[1] = tsdata->factory_mode ? addr & 0x7f : addr & 0x3f;
 216         wrbuf[1] |= tsdata->factory_mode ? 0x80 : 0x40;
 217
 218         error = edt_ft5x06_ts_readwrite(tsdata->client, 2, wrbuf, 2, rdbuf);
 219         if (error)
 220                 return error;
 221
 222         if ((wrbuf[0] ^ wrbuf[1] ^ rdbuf[0]) != rdbuf[1]) {
 223                 dev_err(&tsdata->client->dev,
 224                         "crc error: 0x%02x expected, got 0x%02x\n",
 225                         wrbuf[0] ^ wrbuf[1] ^ rdbuf[0], rdbuf[1]);
 226                 return -EIO;
 227         }
 228
 229         return rdbuf[0];
 230 }
 231
 232 struct edt_ft5x06_attribute {
 233         struct device_attribute dattr;
 234         size_t field_offset;
 235         u8 limit_low;
 236         u8 limit_high;
 237         u8 addr;
 238 };
 239
 240 #define EDT_ATTR(_field, _mode, _addr, _limit_low, _limit_high)         \
 241         struct edt_ft5x06_attribute edt_ft5x06_attr_##_field = {        \
 242                 .dattr = __ATTR(_field, _mode,                          \
 243                                 edt_ft5x06_setting_show,                \
 244                                 edt_ft5x06_setting_store),              \
 245                 .field_offset =                                         \
 246                         offsetof(struct edt_ft5x06_ts_data, _field),    \
 247                 .limit_low = _limit_low,                                \
 248                 .limit_high = _limit_high,                              \
 249                 .addr = _addr,                                          \
 250         }
 251
 252 static ssize_t edt_ft5x06_setting_show(struct device *dev,
 253                                        struct device_attribute *dattr,
 254                                        char *buf)
 255 {
 256         struct i2c_client *client = to_i2c_client(dev);
 257         struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
 258         struct edt_ft5x06_attribute *attr =
 259                         container_of(dattr, struct edt_ft5x06_attribute, dattr);
 260         u8 *field = (u8 *)((char *)tsdata + attr->field_offset);
 261         int val;
 262         size_t count = 0;
 263         int error = 0;
 264
 265         mutex_lock(&tsdata->mutex);
 266
 267         if (tsdata->factory_mode) {
 268                 error = -EIO;
 269                 goto out;
 270         }
 271
 272         val = edt_ft5x06_register_read(tsdata, attr->addr);
 273         if (val < 0) {
 274                 error = val;
 275                 dev_err(&tsdata->client->dev,
 276                         "Failed to fetch attribute %s, error %d\n",
 277                         dattr->attr.name, error);
 278                 goto out;
 279         }
 280
 281         if (val != *field) {
 282                 dev_warn(&tsdata->client->dev,
 283                          "%s: read (%d) and stored value (%d) differ\n",
 284                          dattr->attr.name, val, *field);
 285                 *field = val;
 286         }
 287
 288         count = scnprintf(buf, PAGE_SIZE, "%d\n", val);
 289 out:
 290         mutex_unlock(&tsdata->mutex);
 291         return error ?: count;
 292 }
 293
 294 static ssize_t edt_ft5x06_setting_store(struct device *dev,
 295                                         struct device_attribute *dattr,
 296                                         const char *buf, size_t count)
 297 {
 298         struct i2c_client *client = to_i2c_client(dev);
 299         struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
 300         struct edt_ft5x06_attribute *attr =
 301                         container_of(dattr, struct edt_ft5x06_attribute, dattr);
 302         u8 *field = (u8 *)((char *)tsdata + attr->field_offset);
 303         unsigned int val;
 304         int error;
 305
 306         mutex_lock(&tsdata->mutex);
 307
 308         if (tsdata->factory_mode) {
 309                 error = -EIO;
 310                 goto out;
 311         }
 312
 313         error = kstrtouint(buf, 0, &val);
 314         if (error)
 315                 goto out;
 316
 317         if (val < attr->limit_low || val > attr->limit_high) {
 318                 error = -ERANGE;
 319                 goto out;
 320         }
 321
 322         error = edt_ft5x06_register_write(tsdata, attr->addr, val);
 323         if (error) {
 324                 dev_err(&tsdata->client->dev,
 325                         "Failed to update attribute %s, error: %d\n",
 326                         dattr->attr.name, error);
 327                 goto out;
 328         }
 329
 330         *field = val;
 331
 332 out:
 333         mutex_unlock(&tsdata->mutex);
 334         return error ?: count;
 335 }
 336
 337 static EDT_ATTR(gain, S_IWUSR | S_IRUGO, WORK_REGISTER_GAIN, 0, 31);
 338 static EDT_ATTR(offset, S_IWUSR | S_IRUGO, WORK_REGISTER_OFFSET, 0, 31);
 339 static EDT_ATTR(threshold, S_IWUSR | S_IRUGO,
 340                 WORK_REGISTER_THRESHOLD, 20, 80);
 341 static EDT_ATTR(report_rate, S_IWUSR | S_IRUGO,
 342                 WORK_REGISTER_REPORT_RATE, 3, 14);
 343
 344 static struct attribute *edt_ft5x06_attrs[] = {
 345         &edt_ft5x06_attr_gain.dattr.attr,
 346         &edt_ft5x06_attr_offset.dattr.attr,
 347         &edt_ft5x06_attr_threshold.dattr.attr,
 348         &edt_ft5x06_attr_report_rate.dattr.attr,
 349         NULL
 350 };
 351
 352 static const struct attribute_group edt_ft5x06_attr_group = {
 353         .attrs = edt_ft5x06_attrs,
 354 };
 355
 356 #ifdef CONFIG_DEBUG_FS
 357 static int edt_ft5x06_factory_mode(struct edt_ft5x06_ts_data *tsdata)
 358 {
 359         struct i2c_client *client = tsdata->client;
 360         int retries = EDT_SWITCH_MODE_RETRIES;
 361         int ret;
 362         int error;
 363
 364         disable_irq(client->irq);
 365
 366         if (!tsdata->raw_buffer) {
 367                 tsdata->raw_bufsize = tsdata->num_x * tsdata->num_y *
 368                                       sizeof(u16);
 369                 tsdata->raw_buffer = kzalloc(tsdata->raw_bufsize, GFP_KERNEL);
 370                 if (!tsdata->raw_buffer) {
 371                         error = -ENOMEM;
 372                         goto err_out;
 373                 }
 374         }
 375
 376         /* mode register is 0x3c when in the work mode */
 377         error = edt_ft5x06_register_write(tsdata, WORK_REGISTER_OPMODE, 0x03);
 378         if (error) {
 379                 dev_err(&client->dev,
 380                         "failed to switch to factory mode, error %d\n", error);
 381                 goto err_out;
 382         }
 383
 384         tsdata->factory_mode = true;
 385         do {
 386                 mdelay(EDT_SWITCH_MODE_DELAY);
 387                 /* mode register is 0x01 when in factory mode */
 388                 ret = edt_ft5x06_register_read(tsdata, FACTORY_REGISTER_OPMODE);
 389                 if (ret == 0x03)
 390                         break;
 391         } while (--retries > 0);
 392
 393         if (retries == 0) {
 394                 dev_err(&client->dev, "not in factory mode after %dms.\n",
 395                         EDT_SWITCH_MODE_RETRIES * EDT_SWITCH_MODE_DELAY);
 396                 error = -EIO;
 397                 goto err_out;
 398         }
 399
 400         return 0;
 401
 402 err_out:
 403         kfree(tsdata->raw_buffer);
 404         tsdata->raw_buffer = NULL;
 405         tsdata->factory_mode = false;
 406         enable_irq(client->irq);
 407
 408         return error;
 409 }
 410
 411 static int edt_ft5x06_work_mode(struct edt_ft5x06_ts_data *tsdata)
 412 {
 413         struct i2c_client *client = tsdata->client;
 414         int retries = EDT_SWITCH_MODE_RETRIES;
 415         int ret;
 416         int error;
 417
 418         /* mode register is 0x01 when in the factory mode */
 419         error = edt_ft5x06_register_write(tsdata, FACTORY_REGISTER_OPMODE, 0x1);
 420         if (error) {
 421                 dev_err(&client->dev,
 422                         "failed to switch to work mode, error: %d\n", error);
 423                 return error;
 424         }
 425
 426         tsdata->factory_mode = false;
 427
 428         do {
 429                 mdelay(EDT_SWITCH_MODE_DELAY);
 430                 /* mode register is 0x01 when in factory mode */
 431                 ret = edt_ft5x06_register_read(tsdata, WORK_REGISTER_OPMODE);
 432                 if (ret == 0x01)
 433                         break;
 434         } while (--retries > 0);
 435
 436         if (retries == 0) {
 437                 dev_err(&client->dev, "not in work mode after %dms.\n",
 438                         EDT_SWITCH_MODE_RETRIES * EDT_SWITCH_MODE_DELAY);
 439                 tsdata->factory_mode = true;
 440                 return -EIO;
 441         }
 442
 443         kfree(tsdata->raw_buffer);
 444         tsdata->raw_buffer = NULL;
 445
 446         /* restore parameters */
 447         edt_ft5x06_register_write(tsdata, WORK_REGISTER_THRESHOLD,
 448                                   tsdata->threshold);
 449         edt_ft5x06_register_write(tsdata, WORK_REGISTER_GAIN,
 450                                   tsdata->gain);
 451         edt_ft5x06_register_write(tsdata, WORK_REGISTER_OFFSET,
 452                                   tsdata->offset);
 453         edt_ft5x06_register_write(tsdata, WORK_REGISTER_REPORT_RATE,
 454                                   tsdata->report_rate);
 455
 456         enable_irq(client->irq);
 457
 458         return 0;
 459 }
 460
 461 static int edt_ft5x06_debugfs_mode_get(void *data, u64 *mode)
 462 {
 463         struct edt_ft5x06_ts_data *tsdata = data;
 464
 465         *mode = tsdata->factory_mode;
 466
 467         return 0;
 468 };
 469
 470 static int edt_ft5x06_debugfs_mode_set(void *data, u64 mode)
 471 {
 472         struct edt_ft5x06_ts_data *tsdata = data;
 473         int retval = 0;
 474
 475         if (mode > 1)
 476                 return -ERANGE;
 477
 478         mutex_lock(&tsdata->mutex);
 479
 480         if (mode != tsdata->factory_mode) {
 481                 retval = mode ? edt_ft5x06_factory_mode(tsdata) :
 482                                 edt_ft5x06_work_mode(tsdata);
 483         }
 484
 485         mutex_unlock(&tsdata->mutex);
 486
 487         return retval;
 488 };
 489
 490 DEFINE_SIMPLE_ATTRIBUTE(debugfs_mode_fops, edt_ft5x06_debugfs_mode_get,
 491                         edt_ft5x06_debugfs_mode_set, "%llu\n");
 492
 493 static ssize_t edt_ft5x06_debugfs_raw_data_read(struct file *file,
 494                                 char __user *buf, size_t count, loff_t *off)
 495 {
 496         struct edt_ft5x06_ts_data *tsdata = file->private_data;
 497         struct i2c_client *client = tsdata->client;
 498         int retries  = EDT_RAW_DATA_RETRIES;
 499         int val, i, error;
 500         size_t read = 0;
 501         int colbytes;
 502         char wrbuf[3];
 503         u8 *rdbuf;
 504
 505         if (*off < 0 || *off >= tsdata->raw_bufsize)
 506                 return 0;
 507
 508         mutex_lock(&tsdata->mutex);
 509
 510         if (!tsdata->factory_mode || !tsdata->raw_buffer) {
 511                 error = -EIO;
 512                 goto out;
 513         }
 514
 515         error = edt_ft5x06_register_write(tsdata, 0x08, 0x01);
 516         if (error) {
 517                 dev_dbg(&client->dev,
 518                         "failed to write 0x08 register, error %d\n", error);
 519                 goto out;
 520         }
 521
 522         do {
 523                 msleep(EDT_RAW_DATA_DELAY);
 524                 val = edt_ft5x06_register_read(tsdata, 0x08);
 525                 if (val < 1)
 526                         break;
 527         } while (--retries > 0);
 528
 529         if (val < 0) {
 530                 error = val;
 531                 dev_dbg(&client->dev,
 532                         "failed to read 0x08 register, error %d\n", error);
 533                 goto out;
 534         }
 535
 536         if (retries == 0) {
 537                 dev_dbg(&client->dev,
 538                         "timed out waiting for register to settle\n");
 539                 error = -ETIMEDOUT;
 540                 goto out;
 541         }
 542
 543         rdbuf = tsdata->raw_buffer;
 544         colbytes = tsdata->num_y * sizeof(u16);
 545
 546         wrbuf[0] = 0xf5;
 547         wrbuf[1] = 0x0e;
 548         for (i = 0; i < tsdata->num_x; i++) {
 549                 wrbuf[2] = i;  /* column index */
 550                 error = edt_ft5x06_ts_readwrite(tsdata->client,
 551                                                 sizeof(wrbuf), wrbuf,
 552                                                 colbytes, rdbuf);
 553                 if (error)
 554                         goto out;
 555
 556                 rdbuf += colbytes;
 557         }
 558
 559         read = min_t(size_t, count, tsdata->raw_bufsize - *off);
 560         if (copy_to_user(buf, tsdata->raw_buffer + *off, read)) {
 561                 error = -EFAULT;
 562                 goto out;
 563         }
 564
 565         *off += read;
 566 out:
 567         mutex_unlock(&tsdata->mutex);
 568         return error ?: read;
 569 };
 570
 571
 572 static const struct file_operations debugfs_raw_data_fops = {
 573         .open = simple_open,
 574         .read = edt_ft5x06_debugfs_raw_data_read,
 575 };
 576
 577 static void
 578 edt_ft5x06_ts_prepare_debugfs(struct edt_ft5x06_ts_data *tsdata,
 579                               const char *debugfs_name)
 580 {
 581         tsdata->debug_dir = debugfs_create_dir(debugfs_name, NULL);
 582         if (!tsdata->debug_dir)
 583                 return;
 584
 585         debugfs_create_u16("num_x", S_IRUSR, tsdata->debug_dir, &tsdata->num_x);
 586         debugfs_create_u16("num_y", S_IRUSR, tsdata->debug_dir, &tsdata->num_y);
 587
 588         debugfs_create_file("mode", S_IRUSR | S_IWUSR,
 589                             tsdata->debug_dir, tsdata, &debugfs_mode_fops);
 590         debugfs_create_file("raw_data", S_IRUSR,
 591                             tsdata->debug_dir, tsdata, &debugfs_raw_data_fops);
 592 }
 593
 594 static void
 595 edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
 596 {
 597         if (tsdata->debug_dir)
 598                 debugfs_remove_recursive(tsdata->debug_dir);
 599         kfree(tsdata->raw_buffer);
 600 }
 601
 602 #else
 603
 604 static inline void
 605 edt_ft5x06_ts_prepare_debugfs(struct edt_ft5x06_ts_data *tsdata,
 606                               const char *debugfs_name)
 607 {
 608 }
 609
 610 static inline void
 611 edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
 612 {
 613 }
 614
 615 #endif /* CONFIG_DEBUGFS */
 616
 617
 618
 619 static int edt_ft5x06_ts_reset(struct i2c_client *client,
 620                                          int reset_pin)
 621 {
 622         int error;
 623
 624         if (gpio_is_valid(reset_pin)) {
 625                 /* this pulls reset down, enabling the low active reset */
 626                 error = gpio_request_one(reset_pin, GPIOF_OUT_INIT_LOW,
 627                                          "edt-ft5x06 reset");
 628                 if (error) {
 629                         dev_err(&client->dev,
 630                                 "Failed to request GPIO %d as reset pin, error %d\n",
 631                                 reset_pin, error);
 632                         return error;
 633                 }
 634
 635                 mdelay(50);
 636                 gpio_set_value(reset_pin, 1);
 637                 mdelay(100);
 638         }
 639
 640         return 0;
 641 }
 642
 643 static int edt_ft5x06_ts_identify(struct i2c_client *client,
 644                                             char *model_name,
 645                                             char *fw_version)
 646 {
 647         u8 rdbuf[EDT_NAME_LEN];
 648         char *p;
 649         int error;
 650
 651         error = edt_ft5x06_ts_readwrite(client, 1, "\xbb",
 652                                         EDT_NAME_LEN - 1, rdbuf);
 653         if (error)
 654                 return error;
 655
 656         /* remove last '$' end marker */
 657         rdbuf[EDT_NAME_LEN - 1] = '\0';
 658         if (rdbuf[EDT_NAME_LEN - 2] == '$')
 659                 rdbuf[EDT_NAME_LEN - 2] = '\0';
 660
 661         /* look for Model/Version separator */
 662         p = strchr(rdbuf, '*');
 663         if (p)
 664                 *p++ = '\0';
 665
 666         strlcpy(model_name, rdbuf + 1, EDT_NAME_LEN);
 667         strlcpy(fw_version, p ? p : "", EDT_NAME_LEN);
 668
 669         return 0;
 670 }
 671
 672 #define EDT_ATTR_CHECKSET(name, reg) \
 673         if (pdata->name >= edt_ft5x06_attr_##name.limit_low &&          \
 674             pdata->name <= edt_ft5x06_attr_##name.limit_high)           \
 675                 edt_ft5x06_register_write(tsdata, reg, pdata->name)
 676
 677 static void
 678 edt_ft5x06_ts_get_defaults(struct edt_ft5x06_ts_data *tsdata,
 679                            const struct edt_ft5x06_platform_data *pdata)
 680 {
 681         if (!pdata->use_parameters)
 682                 return;
 683
 684         /* pick up defaults from the platform data */
 685         EDT_ATTR_CHECKSET(threshold, WORK_REGISTER_THRESHOLD);
 686         EDT_ATTR_CHECKSET(gain, WORK_REGISTER_GAIN);
 687         EDT_ATTR_CHECKSET(offset, WORK_REGISTER_OFFSET);
 688         EDT_ATTR_CHECKSET(report_rate, WORK_REGISTER_REPORT_RATE);
 689 }
 690
 691 static void
 692 edt_ft5x06_ts_get_parameters(struct edt_ft5x06_ts_data *tsdata)
 693 {
 694         tsdata->threshold = edt_ft5x06_register_read(tsdata,
 695                                                      WORK_REGISTER_THRESHOLD);
 696         tsdata->gain = edt_ft5x06_register_read(tsdata, WORK_REGISTER_GAIN);
 697         tsdata->offset = edt_ft5x06_register_read(tsdata, WORK_REGISTER_OFFSET);
 698         tsdata->report_rate = edt_ft5x06_register_read(tsdata,
 699                                                 WORK_REGISTER_REPORT_RATE);
 700         tsdata->num_x = edt_ft5x06_register_read(tsdata, WORK_REGISTER_NUM_X);
 701         tsdata->num_y = edt_ft5x06_register_read(tsdata, WORK_REGISTER_NUM_Y);
 702 }
 703
 704 static int edt_ft5x06_ts_probe(struct i2c_client *client,
 705                                          const struct i2c_device_id *id)
 706 {
 707         const struct edt_ft5x06_platform_data *pdata =
 708                                                 client->dev.platform_data;
 709         struct edt_ft5x06_ts_data *tsdata;
 710         struct input_dev *input;
 711         int error;
 712         char fw_version[EDT_NAME_LEN];
 713
 714         dev_dbg(&client->dev, "probing for EDT FT5x06 I2C\n");
 715
 716         if (!pdata) {
 717                 dev_err(&client->dev, "no platform data?\n");
 718                 return -EINVAL;
 719         }
 720
 721         error = edt_ft5x06_ts_reset(client, pdata->reset_pin);
 722         if (error)
 723                 return error;
 724
 725         if (gpio_is_valid(pdata->irq_pin)) {
 726                 error = gpio_request_one(pdata->irq_pin,
 727                                          GPIOF_IN, "edt-ft5x06 irq");
 728                 if (error) {
 729                         dev_err(&client->dev,
 730                                 "Failed to request GPIO %d, error %d\n",
 731                                 pdata->irq_pin, error);
 732                         return error;
 733                 }
 734         }
 735
 736         tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
 737         input = input_allocate_device();
 738         if (!tsdata || !input) {
 739                 dev_err(&client->dev, "failed to allocate driver data.\n");
 740                 error = -ENOMEM;
 741                 goto err_free_mem;
 742         }
 743
 744         mutex_init(&tsdata->mutex);
 745         tsdata->client = client;
 746         tsdata->input = input;
 747         tsdata->factory_mode = false;
 748
 749         error = edt_ft5x06_ts_identify(client, tsdata->name, fw_version);
 750         if (error) {
 751                 dev_err(&client->dev, "touchscreen probe failed\n");
 752                 goto err_free_mem;
 753         }
 754
 755         edt_ft5x06_ts_get_defaults(tsdata, pdata);
 756         edt_ft5x06_ts_get_parameters(tsdata);
 757
 758         dev_dbg(&client->dev,
 759                 "Model \"%s\", Rev. \"%s\", %dx%d sensors\n",
 760                 tsdata->name, fw_version, tsdata->num_x, tsdata->num_y);
 761
 762         input->name = tsdata->name;
 763         input->id.bustype = BUS_I2C;
 764         input->dev.parent = &client->dev;
 765
 766         __set_bit(EV_SYN, input->evbit);
 767         __set_bit(EV_KEY, input->evbit);
 768         __set_bit(EV_ABS, input->evbit);
 769         __set_bit(BTN_TOUCH, input->keybit);
 770         input_set_abs_params(input, ABS_X, 0, tsdata->num_x * 64 - 1, 0, 0);
 771         input_set_abs_params(input, ABS_Y, 0, tsdata->num_y * 64 - 1, 0, 0);
 772         input_set_abs_params(input, ABS_MT_POSITION_X,
 773                              0, tsdata->num_x * 64 - 1, 0, 0);
 774         input_set_abs_params(input, ABS_MT_POSITION_Y,
 775                              0, tsdata->num_y * 64 - 1, 0, 0);
 776         error = input_mt_init_slots(input, MAX_SUPPORT_POINTS, 0);
 777         if (error) {
 778                 dev_err(&client->dev, "Unable to init MT slots.\n");
 779                 goto err_free_mem;
 780         }
 781
 782         input_set_drvdata(input, tsdata);
 783         i2c_set_clientdata(client, tsdata);
 784
 785         error = request_threaded_irq(client->irq, NULL, edt_ft5x06_ts_isr,
 786                                      IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 787                                      client->name, tsdata);
 788         if (error) {
 789                 dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
 790                 goto err_free_mem;
 791         }
 792
 793         error = sysfs_create_group(&client->dev.kobj, &edt_ft5x06_attr_group);
 794         if (error)
 795                 goto err_free_irq;
 796
 797         error = input_register_device(input);
 798         if (error)
 799                 goto err_remove_attrs;
 800
 801         edt_ft5x06_ts_prepare_debugfs(tsdata, dev_driver_string(&client->dev));
 802         device_init_wakeup(&client->dev, 1);
 803
 804         dev_dbg(&client->dev,
 805                 "EDT FT5x06 initialized: IRQ pin %d, Reset pin %d.\n",
 806                 pdata->irq_pin, pdata->reset_pin);
 807
 808         return 0;
 809
 810 err_remove_attrs:
 811         sysfs_remove_group(&client->dev.kobj, &edt_ft5x06_attr_group);
 812 err_free_irq:
 813         free_irq(client->irq, tsdata);
 814 err_free_mem:
 815         input_free_device(input);
 816         kfree(tsdata);
 817
 818         if (gpio_is_valid(pdata->irq_pin))
 819                 gpio_free(pdata->irq_pin);
 820
 821         return error;
 822 }
 823
 824 static int edt_ft5x06_ts_remove(struct i2c_client *client)
 825 {
 826         const struct edt_ft5x06_platform_data *pdata =
 827                                                 dev_get_platdata(&client->dev);
 828         struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
 829
 830         edt_ft5x06_ts_teardown_debugfs(tsdata);
 831         sysfs_remove_group(&client->dev.kobj, &edt_ft5x06_attr_group);
 832
 833         free_irq(client->irq, tsdata);
 834         input_unregister_device(tsdata->input);
 835
 836         if (gpio_is_valid(pdata->irq_pin))
 837                 gpio_free(pdata->irq_pin);
 838         if (gpio_is_valid(pdata->reset_pin))
 839                 gpio_free(pdata->reset_pin);
 840
 841         kfree(tsdata);
 842
 843         return 0;
 844 }
 845
 846 #ifdef CONFIG_PM_SLEEP
 847 static int edt_ft5x06_ts_suspend(struct device *dev)
 848 {
 849         struct i2c_client *client = to_i2c_client(dev);
 850
 851         if (device_may_wakeup(dev))
 852                 enable_irq_wake(client->irq);
 853
 854         return 0;
 855 }
 856
 857 static int edt_ft5x06_ts_resume(struct device *dev)
 858 {
 859         struct i2c_client *client = to_i2c_client(dev);
 860
 861         if (device_may_wakeup(dev))
 862                 disable_irq_wake(client->irq);
 863
 864         return 0;
 865 }
 866 #endif
 867
 868 static SIMPLE_DEV_PM_OPS(edt_ft5x06_ts_pm_ops,
 869                          edt_ft5x06_ts_suspend, edt_ft5x06_ts_resume);
 870
 871 static const struct i2c_device_id edt_ft5x06_ts_id[] = {
 872         { "edt-ft5x06", 0 },
 873         { }
 874 };
 875 MODULE_DEVICE_TABLE(i2c, edt_ft5x06_ts_id);
 876
 877 static struct i2c_driver edt_ft5x06_ts_driver = {
 878         .driver = {
 879                 .owner = THIS_MODULE,
 880                 .name = "edt_ft5x06",
 881                 .pm = &edt_ft5x06_ts_pm_ops,
 882         },
 883         .id_table = edt_ft5x06_ts_id,
 884         .probe    = edt_ft5x06_ts_probe,
 885         .remove   = edt_ft5x06_ts_remove,
 886 };
 887
 888 module_i2c_driver(edt_ft5x06_ts_driver);
 889
 890 MODULE_AUTHOR("Simon Budig <simon.budig@kernelconcepts.de>");
 891 MODULE_DESCRIPTION("EDT FT5x06 I2C Touchscreen Driver");
 892 MODULE_LICENSE("GPL");