1 /* 2 * Driver for Pixcir I2C touchscreen controllers. 3 * 4 * Copyright (C) 2010-2011 Pixcir, Inc. 5 * 6 * This software is licensed under the terms of the GNU General Public 7 * License version 2, as published by the Free Software Foundation, and 8 * may be copied, distributed, and modified under those terms. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public 16 * License along with this library; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #include <linux/delay.h> 21 #include <linux/module.h> 22 #include <linux/interrupt.h> 23 #include <linux/slab.h> 24 #include <linux/i2c.h> 25 #include <linux/input.h> 26 #include <linux/input/mt.h> 27 #include <linux/input/pixcir_ts.h> 28 #include <linux/gpio.h> 29 #include <linux/of.h> 30 #include <linux/of_gpio.h> 31 #include <linux/of_device.h> 32 33 #define PIXCIR_MAX_SLOTS 5 /* Max fingers supported by driver */ 34 35 struct pixcir_i2c_ts_data { 36 struct i2c_client *client; 37 struct input_dev *input; 38 const struct pixcir_ts_platform_data *pdata; 39 bool running; 40 int max_fingers; /* Max fingers supported in this instance */ 41 }; 42 43 struct pixcir_touch { 44 int x; 45 int y; 46 int id; 47 }; 48 49 struct pixcir_report_data { 50 int num_touches; 51 struct pixcir_touch touches[PIXCIR_MAX_SLOTS]; 52 }; 53 54 static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata, 55 struct pixcir_report_data *report) 56 { 57 u8 rdbuf[2 + PIXCIR_MAX_SLOTS * 5]; 58 u8 wrbuf[1] = { 0 }; 59 u8 *bufptr; 60 u8 touch; 61 int ret, i; 62 int readsize; 63 const struct pixcir_i2c_chip_data *chip = &tsdata->pdata->chip; 64 65 memset(report, 0, sizeof(struct pixcir_report_data)); 66 67 i = chip->has_hw_ids ? 1 : 0; 68 readsize = 2 + tsdata->max_fingers * (4 + i); 69 if (readsize > sizeof(rdbuf)) 70 readsize = sizeof(rdbuf); 71 72 ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf)); 73 if (ret != sizeof(wrbuf)) { 74 dev_err(&tsdata->client->dev, 75 "%s: i2c_master_send failed(), ret=%d\n", 76 __func__, ret); 77 return; 78 } 79 80 ret = i2c_master_recv(tsdata->client, rdbuf, readsize); 81 if (ret != sizeof(rdbuf)) { 82 dev_err(&tsdata->client->dev, 83 "%s: i2c_master_recv failed(), ret=%d\n", 84 __func__, ret); 85 return; 86 } 87 88 touch = rdbuf[0] & 0x7; 89 if (touch > tsdata->max_fingers) 90 touch = tsdata->max_fingers; 91 92 report->num_touches = touch; 93 bufptr = &rdbuf[2]; 94 95 for (i = 0; i < touch; i++) { 96 report->touches[i].x = (bufptr[1] << 8) | bufptr[0]; 97 report->touches[i].y = (bufptr[3] << 8) | bufptr[2]; 98 99 if (chip->has_hw_ids) { 100 report->touches[i].id = bufptr[4]; 101 bufptr = bufptr + 5; 102 } else { 103 bufptr = bufptr + 4; 104 } 105 } 106 } 107 108 static void pixcir_ts_report(struct pixcir_i2c_ts_data *ts, 109 struct pixcir_report_data *report) 110 { 111 struct input_mt_pos pos[PIXCIR_MAX_SLOTS]; 112 int slots[PIXCIR_MAX_SLOTS]; 113 struct pixcir_touch *touch; 114 int n, i, slot; 115 struct device *dev = &ts->client->dev; 116 const struct pixcir_i2c_chip_data *chip = &ts->pdata->chip; 117 118 n = report->num_touches; 119 if (n > PIXCIR_MAX_SLOTS) 120 n = PIXCIR_MAX_SLOTS; 121 122 if (!chip->has_hw_ids) { 123 for (i = 0; i < n; i++) { 124 touch = &report->touches[i]; 125 pos[i].x = touch->x; 126 pos[i].y = touch->y; 127 } 128 129 input_mt_assign_slots(ts->input, slots, pos, n); 130 } 131 132 for (i = 0; i < n; i++) { 133 touch = &report->touches[i]; 134 135 if (chip->has_hw_ids) { 136 slot = input_mt_get_slot_by_key(ts->input, touch->id); 137 if (slot < 0) { 138 dev_dbg(dev, "no free slot for id 0x%x\n", 139 touch->id); 140 continue; 141 } 142 } else { 143 slot = slots[i]; 144 } 145 146 input_mt_slot(ts->input, slot); 147 input_mt_report_slot_state(ts->input, 148 MT_TOOL_FINGER, true); 149 150 input_event(ts->input, EV_ABS, ABS_MT_POSITION_X, touch->x); 151 input_event(ts->input, EV_ABS, ABS_MT_POSITION_Y, touch->y); 152 153 dev_dbg(dev, "%d: slot %d, x %d, y %d\n", 154 i, slot, touch->x, touch->y); 155 } 156 157 input_mt_sync_frame(ts->input); 158 input_sync(ts->input); 159 } 160 161 static irqreturn_t pixcir_ts_isr(int irq, void *dev_id) 162 { 163 struct pixcir_i2c_ts_data *tsdata = dev_id; 164 const struct pixcir_ts_platform_data *pdata = tsdata->pdata; 165 struct pixcir_report_data report; 166 167 while (tsdata->running) { 168 /* parse packet */ 169 pixcir_ts_parse(tsdata, &report); 170 171 /* report it */ 172 pixcir_ts_report(tsdata, &report); 173 174 if (gpio_get_value(pdata->gpio_attb)) { 175 if (report.num_touches) { 176 /* 177 * Last report with no finger up? 178 * Do it now then. 179 */ 180 input_mt_sync_frame(tsdata->input); 181 input_sync(tsdata->input); 182 } 183 break; 184 } 185 186 msleep(20); 187 } 188 189 return IRQ_HANDLED; 190 } 191 192 static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts, 193 enum pixcir_power_mode mode) 194 { 195 struct device *dev = &ts->client->dev; 196 int ret; 197 198 ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE); 199 if (ret < 0) { 200 dev_err(dev, "%s: can't read reg 0x%x : %d\n", 201 __func__, PIXCIR_REG_POWER_MODE, ret); 202 return ret; 203 } 204 205 ret &= ~PIXCIR_POWER_MODE_MASK; 206 ret |= mode; 207 208 /* Always AUTO_IDLE */ 209 ret |= PIXCIR_POWER_ALLOW_IDLE; 210 211 ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_POWER_MODE, ret); 212 if (ret < 0) { 213 dev_err(dev, "%s: can't write reg 0x%x : %d\n", 214 __func__, PIXCIR_REG_POWER_MODE, ret); 215 return ret; 216 } 217 218 return 0; 219 } 220 221 /* 222 * Set the interrupt mode for the device i.e. ATTB line behaviour 223 * 224 * @polarity : 1 for active high, 0 for active low. 225 */ 226 static int pixcir_set_int_mode(struct pixcir_i2c_ts_data *ts, 227 enum pixcir_int_mode mode, bool polarity) 228 { 229 struct device *dev = &ts->client->dev; 230 int ret; 231 232 ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE); 233 if (ret < 0) { 234 dev_err(dev, "%s: can't read reg 0x%x : %d\n", 235 __func__, PIXCIR_REG_INT_MODE, ret); 236 return ret; 237 } 238 239 ret &= ~PIXCIR_INT_MODE_MASK; 240 ret |= mode; 241 242 if (polarity) 243 ret |= PIXCIR_INT_POL_HIGH; 244 else 245 ret &= ~PIXCIR_INT_POL_HIGH; 246 247 ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret); 248 if (ret < 0) { 249 dev_err(dev, "%s: can't write reg 0x%x : %d\n", 250 __func__, PIXCIR_REG_INT_MODE, ret); 251 return ret; 252 } 253 254 return 0; 255 } 256 257 /* 258 * Enable/disable interrupt generation 259 */ 260 static int pixcir_int_enable(struct pixcir_i2c_ts_data *ts, bool enable) 261 { 262 struct device *dev = &ts->client->dev; 263 int ret; 264 265 ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE); 266 if (ret < 0) { 267 dev_err(dev, "%s: can't read reg 0x%x : %d\n", 268 __func__, PIXCIR_REG_INT_MODE, ret); 269 return ret; 270 } 271 272 if (enable) 273 ret |= PIXCIR_INT_ENABLE; 274 else 275 ret &= ~PIXCIR_INT_ENABLE; 276 277 ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret); 278 if (ret < 0) { 279 dev_err(dev, "%s: can't write reg 0x%x : %d\n", 280 __func__, PIXCIR_REG_INT_MODE, ret); 281 return ret; 282 } 283 284 return 0; 285 } 286 287 static int pixcir_start(struct pixcir_i2c_ts_data *ts) 288 { 289 struct device *dev = &ts->client->dev; 290 int error; 291 292 /* LEVEL_TOUCH interrupt with active low polarity */ 293 error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0); 294 if (error) { 295 dev_err(dev, "Failed to set interrupt mode: %d\n", error); 296 return error; 297 } 298 299 ts->running = true; 300 mb(); /* Update status before IRQ can fire */ 301 302 /* enable interrupt generation */ 303 error = pixcir_int_enable(ts, true); 304 if (error) { 305 dev_err(dev, "Failed to enable interrupt generation: %d\n", 306 error); 307 return error; 308 } 309 310 return 0; 311 } 312 313 static int pixcir_stop(struct pixcir_i2c_ts_data *ts) 314 { 315 int error; 316 317 /* Disable interrupt generation */ 318 error = pixcir_int_enable(ts, false); 319 if (error) { 320 dev_err(&ts->client->dev, 321 "Failed to disable interrupt generation: %d\n", 322 error); 323 return error; 324 } 325 326 /* Exit ISR if running, no more report parsing */ 327 ts->running = false; 328 mb(); /* update status before we synchronize irq */ 329 330 /* Wait till running ISR is complete */ 331 synchronize_irq(ts->client->irq); 332 333 return 0; 334 } 335 336 static int pixcir_input_open(struct input_dev *dev) 337 { 338 struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev); 339 340 return pixcir_start(ts); 341 } 342 343 static void pixcir_input_close(struct input_dev *dev) 344 { 345 struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev); 346 347 pixcir_stop(ts); 348 } 349 350 #ifdef CONFIG_PM_SLEEP 351 static int pixcir_i2c_ts_suspend(struct device *dev) 352 { 353 struct i2c_client *client = to_i2c_client(dev); 354 struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client); 355 struct input_dev *input = ts->input; 356 int ret = 0; 357 358 mutex_lock(&input->mutex); 359 360 if (device_may_wakeup(&client->dev)) { 361 if (!input->users) { 362 ret = pixcir_start(ts); 363 if (ret) { 364 dev_err(dev, "Failed to start\n"); 365 goto unlock; 366 } 367 } 368 369 enable_irq_wake(client->irq); 370 } else if (input->users) { 371 ret = pixcir_stop(ts); 372 } 373 374 unlock: 375 mutex_unlock(&input->mutex); 376 377 return ret; 378 } 379 380 static int pixcir_i2c_ts_resume(struct device *dev) 381 { 382 struct i2c_client *client = to_i2c_client(dev); 383 struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client); 384 struct input_dev *input = ts->input; 385 int ret = 0; 386 387 mutex_lock(&input->mutex); 388 389 if (device_may_wakeup(&client->dev)) { 390 disable_irq_wake(client->irq); 391 392 if (!input->users) { 393 ret = pixcir_stop(ts); 394 if (ret) { 395 dev_err(dev, "Failed to stop\n"); 396 goto unlock; 397 } 398 } 399 } else if (input->users) { 400 ret = pixcir_start(ts); 401 } 402 403 unlock: 404 mutex_unlock(&input->mutex); 405 406 return ret; 407 } 408 #endif 409 410 static SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops, 411 pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume); 412 413 #ifdef CONFIG_OF 414 static const struct of_device_id pixcir_of_match[]; 415 416 static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev) 417 { 418 struct pixcir_ts_platform_data *pdata; 419 struct device_node *np = dev->of_node; 420 const struct of_device_id *match; 421 422 match = of_match_device(of_match_ptr(pixcir_of_match), dev); 423 if (!match) 424 return ERR_PTR(-EINVAL); 425 426 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 427 if (!pdata) 428 return ERR_PTR(-ENOMEM); 429 430 pdata->chip = *(const struct pixcir_i2c_chip_data *)match->data; 431 432 pdata->gpio_attb = of_get_named_gpio(np, "attb-gpio", 0); 433 /* gpio_attb validity is checked in probe */ 434 435 if (of_property_read_u32(np, "touchscreen-size-x", &pdata->x_max)) { 436 dev_err(dev, "Failed to get touchscreen-size-x property\n"); 437 return ERR_PTR(-EINVAL); 438 } 439 pdata->x_max -= 1; 440 441 if (of_property_read_u32(np, "touchscreen-size-y", &pdata->y_max)) { 442 dev_err(dev, "Failed to get touchscreen-size-y property\n"); 443 return ERR_PTR(-EINVAL); 444 } 445 pdata->y_max -= 1; 446 447 dev_dbg(dev, "%s: x %d, y %d, gpio %d\n", __func__, 448 pdata->x_max + 1, pdata->y_max + 1, pdata->gpio_attb); 449 450 return pdata; 451 } 452 #else 453 static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev) 454 { 455 return ERR_PTR(-EINVAL); 456 } 457 #endif 458 459 static int pixcir_i2c_ts_probe(struct i2c_client *client, 460 const struct i2c_device_id *id) 461 { 462 const struct pixcir_ts_platform_data *pdata = 463 dev_get_platdata(&client->dev); 464 struct device *dev = &client->dev; 465 struct device_node *np = dev->of_node; 466 struct pixcir_i2c_ts_data *tsdata; 467 struct input_dev *input; 468 int error; 469 470 if (np && !pdata) { 471 pdata = pixcir_parse_dt(dev); 472 if (IS_ERR(pdata)) 473 return PTR_ERR(pdata); 474 } 475 476 if (!pdata) { 477 dev_err(&client->dev, "platform data not defined\n"); 478 return -EINVAL; 479 } 480 481 if (!gpio_is_valid(pdata->gpio_attb)) { 482 dev_err(dev, "Invalid gpio_attb in pdata\n"); 483 return -EINVAL; 484 } 485 486 if (!pdata->chip.max_fingers) { 487 dev_err(dev, "Invalid max_fingers in pdata\n"); 488 return -EINVAL; 489 } 490 491 tsdata = devm_kzalloc(dev, sizeof(*tsdata), GFP_KERNEL); 492 if (!tsdata) 493 return -ENOMEM; 494 495 input = devm_input_allocate_device(dev); 496 if (!input) { 497 dev_err(dev, "Failed to allocate input device\n"); 498 return -ENOMEM; 499 } 500 501 tsdata->client = client; 502 tsdata->input = input; 503 tsdata->pdata = pdata; 504 505 input->name = client->name; 506 input->id.bustype = BUS_I2C; 507 input->open = pixcir_input_open; 508 input->close = pixcir_input_close; 509 input->dev.parent = &client->dev; 510 511 __set_bit(EV_KEY, input->evbit); 512 __set_bit(EV_ABS, input->evbit); 513 __set_bit(BTN_TOUCH, input->keybit); 514 input_set_abs_params(input, ABS_X, 0, pdata->x_max, 0, 0); 515 input_set_abs_params(input, ABS_Y, 0, pdata->y_max, 0, 0); 516 input_set_abs_params(input, ABS_MT_POSITION_X, 0, pdata->x_max, 0, 0); 517 input_set_abs_params(input, ABS_MT_POSITION_Y, 0, pdata->y_max, 0, 0); 518 519 tsdata->max_fingers = tsdata->pdata->chip.max_fingers; 520 if (tsdata->max_fingers > PIXCIR_MAX_SLOTS) { 521 tsdata->max_fingers = PIXCIR_MAX_SLOTS; 522 dev_info(dev, "Limiting maximum fingers to %d\n", 523 tsdata->max_fingers); 524 } 525 526 error = input_mt_init_slots(input, tsdata->max_fingers, 527 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); 528 if (error) { 529 dev_err(dev, "Error initializing Multi-Touch slots\n"); 530 return error; 531 } 532 533 input_set_drvdata(input, tsdata); 534 535 error = devm_gpio_request_one(dev, pdata->gpio_attb, 536 GPIOF_DIR_IN, "pixcir_i2c_attb"); 537 if (error) { 538 dev_err(dev, "Failed to request ATTB gpio\n"); 539 return error; 540 } 541 542 error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr, 543 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 544 client->name, tsdata); 545 if (error) { 546 dev_err(dev, "failed to request irq %d\n", client->irq); 547 return error; 548 } 549 550 /* Always be in IDLE mode to save power, device supports auto wake */ 551 error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE); 552 if (error) { 553 dev_err(dev, "Failed to set IDLE mode\n"); 554 return error; 555 } 556 557 /* Stop device till opened */ 558 error = pixcir_stop(tsdata); 559 if (error) 560 return error; 561 562 error = input_register_device(input); 563 if (error) 564 return error; 565 566 i2c_set_clientdata(client, tsdata); 567 device_init_wakeup(&client->dev, 1); 568 569 return 0; 570 } 571 572 static int pixcir_i2c_ts_remove(struct i2c_client *client) 573 { 574 device_init_wakeup(&client->dev, 0); 575 576 return 0; 577 } 578 579 static const struct i2c_device_id pixcir_i2c_ts_id[] = { 580 { "pixcir_ts", 0 }, 581 { "pixcir_tangoc", 0 }, 582 { } 583 }; 584 MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id); 585 586 #ifdef CONFIG_OF 587 static const struct pixcir_i2c_chip_data pixcir_ts_data = { 588 .max_fingers = 2, 589 /* no hw id support */ 590 }; 591 592 static const struct pixcir_i2c_chip_data pixcir_tangoc_data = { 593 .max_fingers = 5, 594 .has_hw_ids = true, 595 }; 596 597 static const struct of_device_id pixcir_of_match[] = { 598 { .compatible = "pixcir,pixcir_ts", .data = &pixcir_ts_data }, 599 { .compatible = "pixcir,pixcir_tangoc", .data = &pixcir_tangoc_data }, 600 { } 601 }; 602 MODULE_DEVICE_TABLE(of, pixcir_of_match); 603 #endif 604 605 static struct i2c_driver pixcir_i2c_ts_driver = { 606 .driver = { 607 .owner = THIS_MODULE, 608 .name = "pixcir_ts", 609 .pm = &pixcir_dev_pm_ops, 610 .of_match_table = of_match_ptr(pixcir_of_match), 611 }, 612 .probe = pixcir_i2c_ts_probe, 613 .remove = pixcir_i2c_ts_remove, 614 .id_table = pixcir_i2c_ts_id, 615 }; 616 617 module_i2c_driver(pixcir_i2c_ts_driver); 618 619 MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>"); 620 MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver"); 621 MODULE_LICENSE("GPL"); 622