1 /* 2 * Synaptics touchpad with I2C interface 3 * 4 * Copyright (C) 2009 Compulab, Ltd. 5 * Mike Rapoport <mike@compulab.co.il> 6 * Igor Grinberg <grinberg@compulab.co.il> 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file COPYING in the main directory of this archive for 10 * more details. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/i2c.h> 15 #include <linux/irq.h> 16 #include <linux/interrupt.h> 17 #include <linux/input.h> 18 #include <linux/delay.h> 19 #include <linux/workqueue.h> 20 #include <linux/slab.h> 21 #include <linux/pm.h> 22 23 #define DRIVER_NAME "synaptics_i2c" 24 /* maximum product id is 15 characters */ 25 #define PRODUCT_ID_LENGTH 15 26 #define REGISTER_LENGTH 8 27 28 /* 29 * after soft reset, we should wait for 1 ms 30 * before the device becomes operational 31 */ 32 #define SOFT_RESET_DELAY_US 3000 33 /* and after hard reset, we should wait for max 500ms */ 34 #define HARD_RESET_DELAY_MS 500 35 36 /* Registers by SMBus address */ 37 #define PAGE_SEL_REG 0xff 38 #define DEVICE_STATUS_REG 0x09 39 40 /* Registers by RMI address */ 41 #define DEV_CONTROL_REG 0x0000 42 #define INTERRUPT_EN_REG 0x0001 43 #define ERR_STAT_REG 0x0002 44 #define INT_REQ_STAT_REG 0x0003 45 #define DEV_COMMAND_REG 0x0004 46 47 #define RMI_PROT_VER_REG 0x0200 48 #define MANUFACT_ID_REG 0x0201 49 #define PHYS_INT_VER_REG 0x0202 50 #define PROD_PROPERTY_REG 0x0203 51 #define INFO_QUERY_REG0 0x0204 52 #define INFO_QUERY_REG1 (INFO_QUERY_REG0 + 1) 53 #define INFO_QUERY_REG2 (INFO_QUERY_REG0 + 2) 54 #define INFO_QUERY_REG3 (INFO_QUERY_REG0 + 3) 55 56 #define PRODUCT_ID_REG0 0x0210 57 #define PRODUCT_ID_REG1 (PRODUCT_ID_REG0 + 1) 58 #define PRODUCT_ID_REG2 (PRODUCT_ID_REG0 + 2) 59 #define PRODUCT_ID_REG3 (PRODUCT_ID_REG0 + 3) 60 #define PRODUCT_ID_REG4 (PRODUCT_ID_REG0 + 4) 61 #define PRODUCT_ID_REG5 (PRODUCT_ID_REG0 + 5) 62 #define PRODUCT_ID_REG6 (PRODUCT_ID_REG0 + 6) 63 #define PRODUCT_ID_REG7 (PRODUCT_ID_REG0 + 7) 64 #define PRODUCT_ID_REG8 (PRODUCT_ID_REG0 + 8) 65 #define PRODUCT_ID_REG9 (PRODUCT_ID_REG0 + 9) 66 #define PRODUCT_ID_REG10 (PRODUCT_ID_REG0 + 10) 67 #define PRODUCT_ID_REG11 (PRODUCT_ID_REG0 + 11) 68 #define PRODUCT_ID_REG12 (PRODUCT_ID_REG0 + 12) 69 #define PRODUCT_ID_REG13 (PRODUCT_ID_REG0 + 13) 70 #define PRODUCT_ID_REG14 (PRODUCT_ID_REG0 + 14) 71 #define PRODUCT_ID_REG15 (PRODUCT_ID_REG0 + 15) 72 73 #define DATA_REG0 0x0400 74 #define ABS_PRESSURE_REG 0x0401 75 #define ABS_MSB_X_REG 0x0402 76 #define ABS_LSB_X_REG (ABS_MSB_X_REG + 1) 77 #define ABS_MSB_Y_REG 0x0404 78 #define ABS_LSB_Y_REG (ABS_MSB_Y_REG + 1) 79 #define REL_X_REG 0x0406 80 #define REL_Y_REG 0x0407 81 82 #define DEV_QUERY_REG0 0x1000 83 #define DEV_QUERY_REG1 (DEV_QUERY_REG0 + 1) 84 #define DEV_QUERY_REG2 (DEV_QUERY_REG0 + 2) 85 #define DEV_QUERY_REG3 (DEV_QUERY_REG0 + 3) 86 #define DEV_QUERY_REG4 (DEV_QUERY_REG0 + 4) 87 #define DEV_QUERY_REG5 (DEV_QUERY_REG0 + 5) 88 #define DEV_QUERY_REG6 (DEV_QUERY_REG0 + 6) 89 #define DEV_QUERY_REG7 (DEV_QUERY_REG0 + 7) 90 #define DEV_QUERY_REG8 (DEV_QUERY_REG0 + 8) 91 92 #define GENERAL_2D_CONTROL_REG 0x1041 93 #define SENSOR_SENSITIVITY_REG 0x1044 94 #define SENS_MAX_POS_MSB_REG 0x1046 95 #define SENS_MAX_POS_LSB_REG (SENS_MAX_POS_UPPER_REG + 1) 96 97 /* Register bits */ 98 /* Device Control Register Bits */ 99 #define REPORT_RATE_1ST_BIT 6 100 101 /* Interrupt Enable Register Bits (INTERRUPT_EN_REG) */ 102 #define F10_ABS_INT_ENA 0 103 #define F10_REL_INT_ENA 1 104 #define F20_INT_ENA 2 105 106 /* Interrupt Request Register Bits (INT_REQ_STAT_REG | DEVICE_STATUS_REG) */ 107 #define F10_ABS_INT_REQ 0 108 #define F10_REL_INT_REQ 1 109 #define F20_INT_REQ 2 110 /* Device Status Register Bits (DEVICE_STATUS_REG) */ 111 #define STAT_CONFIGURED 6 112 #define STAT_ERROR 7 113 114 /* Device Command Register Bits (DEV_COMMAND_REG) */ 115 #define RESET_COMMAND 0x01 116 #define REZERO_COMMAND 0x02 117 118 /* Data Register 0 Bits (DATA_REG0) */ 119 #define GESTURE 3 120 121 /* Device Query Registers Bits */ 122 /* DEV_QUERY_REG3 */ 123 #define HAS_PALM_DETECT 1 124 #define HAS_MULTI_FING 2 125 #define HAS_SCROLLER 4 126 #define HAS_2D_SCROLL 5 127 128 /* General 2D Control Register Bits (GENERAL_2D_CONTROL_REG) */ 129 #define NO_DECELERATION 1 130 #define REDUCE_REPORTING 3 131 #define NO_FILTER 5 132 133 /* Function Masks */ 134 /* Device Control Register Masks (DEV_CONTROL_REG) */ 135 #define REPORT_RATE_MSK 0xc0 136 #define SLEEP_MODE_MSK 0x07 137 138 /* Device Sleep Modes */ 139 #define FULL_AWAKE 0x0 140 #define NORMAL_OP 0x1 141 #define LOW_PWR_OP 0x2 142 #define VERY_LOW_PWR_OP 0x3 143 #define SENS_SLEEP 0x4 144 #define SLEEP_MOD 0x5 145 #define DEEP_SLEEP 0x6 146 #define HIBERNATE 0x7 147 148 /* Interrupt Register Mask */ 149 /* (INT_REQ_STAT_REG | DEVICE_STATUS_REG | INTERRUPT_EN_REG) */ 150 #define INT_ENA_REQ_MSK 0x07 151 #define INT_ENA_ABS_MSK 0x01 152 #define INT_ENA_REL_MSK 0x02 153 #define INT_ENA_F20_MSK 0x04 154 155 /* Device Status Register Masks (DEVICE_STATUS_REG) */ 156 #define CONFIGURED_MSK 0x40 157 #define ERROR_MSK 0x80 158 159 /* Data Register 0 Masks */ 160 #define FINGER_WIDTH_MSK 0xf0 161 #define GESTURE_MSK 0x08 162 #define SENSOR_STATUS_MSK 0x07 163 164 /* 165 * MSB Position Register Masks 166 * ABS_MSB_X_REG | ABS_MSB_Y_REG | SENS_MAX_POS_MSB_REG | 167 * DEV_QUERY_REG3 | DEV_QUERY_REG5 168 */ 169 #define MSB_POSITION_MSK 0x1f 170 171 /* Device Query Registers Masks */ 172 173 /* DEV_QUERY_REG2 */ 174 #define NUM_EXTRA_POS_MSK 0x07 175 176 /* When in IRQ mode read the device every THREAD_IRQ_SLEEP_SECS */ 177 #define THREAD_IRQ_SLEEP_SECS 2 178 #define THREAD_IRQ_SLEEP_MSECS (THREAD_IRQ_SLEEP_SECS * MSEC_PER_SEC) 179 180 /* 181 * When in Polling mode and no data received for NO_DATA_THRES msecs 182 * reduce the polling rate to NO_DATA_SLEEP_MSECS 183 */ 184 #define NO_DATA_THRES (MSEC_PER_SEC) 185 #define NO_DATA_SLEEP_MSECS (MSEC_PER_SEC / 4) 186 187 /* Control touchpad's No Deceleration option */ 188 static bool no_decel = true; 189 module_param(no_decel, bool, 0644); 190 MODULE_PARM_DESC(no_decel, "No Deceleration. Default = 1 (on)"); 191 192 /* Control touchpad's Reduced Reporting option */ 193 static bool reduce_report; 194 module_param(reduce_report, bool, 0644); 195 MODULE_PARM_DESC(reduce_report, "Reduced Reporting. Default = 0 (off)"); 196 197 /* Control touchpad's No Filter option */ 198 static bool no_filter; 199 module_param(no_filter, bool, 0644); 200 MODULE_PARM_DESC(no_filter, "No Filter. Default = 0 (off)"); 201 202 /* 203 * touchpad Attention line is Active Low and Open Drain, 204 * therefore should be connected to pulled up line 205 * and the irq configuration should be set to Falling Edge Trigger 206 */ 207 /* Control IRQ / Polling option */ 208 static bool polling_req; 209 module_param(polling_req, bool, 0444); 210 MODULE_PARM_DESC(polling_req, "Request Polling. Default = 0 (use irq)"); 211 212 /* Control Polling Rate */ 213 static int scan_rate = 80; 214 module_param(scan_rate, int, 0644); 215 MODULE_PARM_DESC(scan_rate, "Polling rate in times/sec. Default = 80"); 216 217 /* The main device structure */ 218 struct synaptics_i2c { 219 struct i2c_client *client; 220 struct input_dev *input; 221 struct delayed_work dwork; 222 int no_data_count; 223 int no_decel_param; 224 int reduce_report_param; 225 int no_filter_param; 226 int scan_rate_param; 227 int scan_ms; 228 }; 229 230 static inline void set_scan_rate(struct synaptics_i2c *touch, int scan_rate) 231 { 232 touch->scan_ms = MSEC_PER_SEC / scan_rate; 233 touch->scan_rate_param = scan_rate; 234 } 235 236 /* 237 * Driver's initial design makes no race condition possible on i2c bus, 238 * so there is no need in any locking. 239 * Keep it in mind, while playing with the code. 240 */ 241 static s32 synaptics_i2c_reg_get(struct i2c_client *client, u16 reg) 242 { 243 int error; 244 245 error = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8); 246 if (error) 247 return error; 248 249 return i2c_smbus_read_byte_data(client, reg & 0xff); 250 } 251 252 static s32 synaptics_i2c_reg_set(struct i2c_client *client, u16 reg, u8 val) 253 { 254 int error; 255 256 error = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8); 257 if (error) 258 return error; 259 260 error = i2c_smbus_write_byte_data(client, reg & 0xff, val); 261 if (error) 262 return error; 263 264 return error; 265 } 266 267 static s32 synaptics_i2c_word_get(struct i2c_client *client, u16 reg) 268 { 269 int error; 270 271 error = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8); 272 if (error) 273 return error; 274 275 return i2c_smbus_read_word_data(client, reg & 0xff); 276 } 277 278 static int synaptics_i2c_config(struct i2c_client *client) 279 { 280 int control; 281 int error; 282 u8 int_en; 283 284 /* set Report Rate to Device Highest (>=80) and Sleep to normal */ 285 error = synaptics_i2c_reg_set(client, DEV_CONTROL_REG, 0xc1); 286 if (error) 287 return error; 288 289 /* set Interrupt Disable to Func20 / Enable to Func10) */ 290 int_en = (polling_req) ? 0 : INT_ENA_ABS_MSK | INT_ENA_REL_MSK; 291 error = synaptics_i2c_reg_set(client, INTERRUPT_EN_REG, int_en); 292 if (error) 293 return error; 294 295 control = synaptics_i2c_reg_get(client, GENERAL_2D_CONTROL_REG); 296 /* No Deceleration */ 297 control |= no_decel ? 1 << NO_DECELERATION : 0; 298 /* Reduced Reporting */ 299 control |= reduce_report ? 1 << REDUCE_REPORTING : 0; 300 /* No Filter */ 301 control |= no_filter ? 1 << NO_FILTER : 0; 302 error = synaptics_i2c_reg_set(client, GENERAL_2D_CONTROL_REG, control); 303 if (error) 304 return error; 305 306 return 0; 307 } 308 309 static int synaptics_i2c_reset_config(struct i2c_client *client) 310 { 311 int error; 312 313 /* Reset the Touchpad */ 314 error = synaptics_i2c_reg_set(client, DEV_COMMAND_REG, RESET_COMMAND); 315 if (error) { 316 dev_err(&client->dev, "Unable to reset device\n"); 317 return error; 318 } 319 320 usleep_range(SOFT_RESET_DELAY_US, SOFT_RESET_DELAY_US + 100); 321 error = synaptics_i2c_config(client); 322 if (error) { 323 dev_err(&client->dev, "Unable to config device\n"); 324 return error; 325 } 326 327 return 0; 328 } 329 330 static int synaptics_i2c_check_error(struct i2c_client *client) 331 { 332 int status; 333 int error; 334 335 status = i2c_smbus_read_byte_data(client, DEVICE_STATUS_REG) & 336 (CONFIGURED_MSK | ERROR_MSK); 337 338 if (status != CONFIGURED_MSK) { 339 error = synaptics_i2c_reset_config(client); 340 if (error) 341 return error; 342 } 343 344 return 0; 345 } 346 347 static bool synaptics_i2c_get_input(struct synaptics_i2c *touch) 348 { 349 struct input_dev *input = touch->input; 350 int xy_delta, gesture; 351 s32 data; 352 s8 x_delta, y_delta; 353 354 /* Deal with spontaneous resets and errors */ 355 if (synaptics_i2c_check_error(touch->client)) 356 return false; 357 358 /* Get Gesture Bit */ 359 data = synaptics_i2c_reg_get(touch->client, DATA_REG0); 360 gesture = (data >> GESTURE) & 0x1; 361 362 /* 363 * Get Relative axes. we have to get them in one shot, 364 * so we get 2 bytes starting from REL_X_REG. 365 */ 366 xy_delta = synaptics_i2c_word_get(touch->client, REL_X_REG) & 0xffff; 367 368 /* Separate X from Y */ 369 x_delta = xy_delta & 0xff; 370 y_delta = (xy_delta >> REGISTER_LENGTH) & 0xff; 371 372 /* Report the button event */ 373 input_report_key(input, BTN_LEFT, gesture); 374 375 /* Report the deltas */ 376 input_report_rel(input, REL_X, x_delta); 377 input_report_rel(input, REL_Y, -y_delta); 378 input_sync(input); 379 380 return xy_delta || gesture; 381 } 382 383 static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id) 384 { 385 struct synaptics_i2c *touch = dev_id; 386 387 mod_delayed_work(system_dfl_wq, &touch->dwork, 0); 388 389 return IRQ_HANDLED; 390 } 391 392 static void synaptics_i2c_check_params(struct synaptics_i2c *touch) 393 { 394 bool reset = false; 395 396 if (scan_rate != touch->scan_rate_param) 397 set_scan_rate(touch, scan_rate); 398 399 if (no_decel != touch->no_decel_param) { 400 touch->no_decel_param = no_decel; 401 reset = true; 402 } 403 404 if (no_filter != touch->no_filter_param) { 405 touch->no_filter_param = no_filter; 406 reset = true; 407 } 408 409 if (reduce_report != touch->reduce_report_param) { 410 touch->reduce_report_param = reduce_report; 411 reset = true; 412 } 413 414 if (reset) 415 synaptics_i2c_reset_config(touch->client); 416 } 417 418 /* Control the Device polling rate / Work Handler sleep time */ 419 static unsigned long synaptics_i2c_adjust_delay(struct synaptics_i2c *touch, 420 bool have_data) 421 { 422 unsigned long delay, nodata_count_thres; 423 424 if (polling_req) { 425 delay = touch->scan_ms; 426 if (have_data) { 427 touch->no_data_count = 0; 428 } else { 429 nodata_count_thres = NO_DATA_THRES / touch->scan_ms; 430 if (touch->no_data_count < nodata_count_thres) 431 touch->no_data_count++; 432 else 433 delay = NO_DATA_SLEEP_MSECS; 434 } 435 return msecs_to_jiffies(delay); 436 } 437 438 delay = msecs_to_jiffies(THREAD_IRQ_SLEEP_MSECS); 439 return round_jiffies_relative(delay); 440 } 441 442 /* Work Handler */ 443 static void synaptics_i2c_work_handler(struct work_struct *work) 444 { 445 bool have_data; 446 struct synaptics_i2c *touch = 447 container_of(work, struct synaptics_i2c, dwork.work); 448 unsigned long delay; 449 450 synaptics_i2c_check_params(touch); 451 452 have_data = synaptics_i2c_get_input(touch); 453 delay = synaptics_i2c_adjust_delay(touch, have_data); 454 455 /* 456 * While interrupt driven, there is no real need to poll the device. 457 * But touchpads are very sensitive, so there could be errors 458 * related to physical environment and the attention line isn't 459 * necessarily asserted. In such case we can lose the touchpad. 460 * We poll the device once in THREAD_IRQ_SLEEP_SECS and 461 * if error is detected, we try to reset and reconfigure the touchpad. 462 */ 463 mod_delayed_work(system_dfl_wq, &touch->dwork, delay); 464 } 465 466 static int synaptics_i2c_open(struct input_dev *input) 467 { 468 struct synaptics_i2c *touch = input_get_drvdata(input); 469 int error; 470 471 error = synaptics_i2c_reset_config(touch->client); 472 if (error) 473 return error; 474 475 if (polling_req) 476 mod_delayed_work(system_dfl_wq, &touch->dwork, 477 msecs_to_jiffies(NO_DATA_SLEEP_MSECS)); 478 479 return 0; 480 } 481 482 static void synaptics_i2c_close(struct input_dev *input) 483 { 484 struct synaptics_i2c *touch = input_get_drvdata(input); 485 486 if (!polling_req) 487 synaptics_i2c_reg_set(touch->client, INTERRUPT_EN_REG, 0); 488 489 cancel_delayed_work_sync(&touch->dwork); 490 491 /* Save some power */ 492 synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP); 493 } 494 495 static void synaptics_i2c_set_input_params(struct synaptics_i2c *touch) 496 { 497 struct input_dev *input = touch->input; 498 499 input->name = touch->client->name; 500 input->phys = touch->client->adapter->name; 501 input->id.bustype = BUS_I2C; 502 input->id.version = synaptics_i2c_word_get(touch->client, 503 INFO_QUERY_REG0); 504 input->open = synaptics_i2c_open; 505 input->close = synaptics_i2c_close; 506 input_set_drvdata(input, touch); 507 508 /* Register the device as mouse */ 509 input_set_capability(input, EV_REL, REL_X); 510 input_set_capability(input, EV_REL, REL_Y); 511 512 /* Register device's buttons and keys */ 513 input_set_capability(input, EV_KEY, BTN_LEFT); 514 } 515 516 static int synaptics_i2c_probe(struct i2c_client *client) 517 { 518 struct device *dev = &client->dev; 519 struct synaptics_i2c *touch; 520 int error; 521 522 touch = devm_kzalloc(dev, sizeof(*touch), GFP_KERNEL); 523 if (!touch) 524 return -ENOMEM; 525 526 touch->client = client; 527 touch->no_decel_param = no_decel; 528 touch->scan_rate_param = scan_rate; 529 set_scan_rate(touch, scan_rate); 530 INIT_DELAYED_WORK(&touch->dwork, synaptics_i2c_work_handler); 531 532 error = synaptics_i2c_reset_config(client); 533 if (error) 534 return error; 535 536 if (client->irq <= 0) 537 polling_req = true; 538 539 touch->input = devm_input_allocate_device(dev); 540 if (!touch->input) 541 return -ENOMEM; 542 543 synaptics_i2c_set_input_params(touch); 544 545 if (!polling_req) { 546 dev_dbg(dev, "Requesting IRQ: %d\n", client->irq); 547 548 error = devm_request_irq(dev, client->irq, synaptics_i2c_irq, 549 IRQ_TYPE_EDGE_FALLING, 550 DRIVER_NAME, touch); 551 if (error) { 552 dev_warn(dev, "IRQ request failed: %d, falling back to polling\n", 553 error); 554 polling_req = true; 555 synaptics_i2c_reg_set(client, INTERRUPT_EN_REG, 0); 556 } 557 } 558 559 if (polling_req) 560 dev_dbg(dev, "Using polling at rate: %d times/sec\n", scan_rate); 561 562 /* Register the device in input subsystem */ 563 error = input_register_device(touch->input); 564 if (error) { 565 dev_err(dev, "Input device register failed: %d\n", error); 566 return error; 567 } 568 569 i2c_set_clientdata(client, touch); 570 571 return 0; 572 } 573 574 static int synaptics_i2c_suspend(struct device *dev) 575 { 576 struct i2c_client *client = to_i2c_client(dev); 577 struct synaptics_i2c *touch = i2c_get_clientdata(client); 578 579 cancel_delayed_work_sync(&touch->dwork); 580 581 /* Save some power */ 582 synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP); 583 584 return 0; 585 } 586 587 static int synaptics_i2c_resume(struct device *dev) 588 { 589 struct i2c_client *client = to_i2c_client(dev); 590 struct synaptics_i2c *touch = i2c_get_clientdata(client); 591 struct input_dev *input = touch->input; 592 int error; 593 594 error = synaptics_i2c_reset_config(client); 595 if (error) 596 return error; 597 598 guard(mutex)(&input->mutex); 599 if (input_device_enabled(input)) 600 mod_delayed_work(system_dfl_wq, &touch->dwork, 601 msecs_to_jiffies(NO_DATA_SLEEP_MSECS)); 602 603 return 0; 604 } 605 606 static DEFINE_SIMPLE_DEV_PM_OPS(synaptics_i2c_pm, synaptics_i2c_suspend, 607 synaptics_i2c_resume); 608 609 static const struct i2c_device_id synaptics_i2c_id_table[] = { 610 { "synaptics_i2c" }, 611 { } 612 }; 613 MODULE_DEVICE_TABLE(i2c, synaptics_i2c_id_table); 614 615 #ifdef CONFIG_OF 616 static const struct of_device_id synaptics_i2c_of_match[] = { 617 { .compatible = "synaptics,synaptics_i2c", }, 618 { }, 619 }; 620 MODULE_DEVICE_TABLE(of, synaptics_i2c_of_match); 621 #endif 622 623 static struct i2c_driver synaptics_i2c_driver = { 624 .driver = { 625 .name = DRIVER_NAME, 626 .of_match_table = of_match_ptr(synaptics_i2c_of_match), 627 .pm = pm_sleep_ptr(&synaptics_i2c_pm), 628 }, 629 630 .probe = synaptics_i2c_probe, 631 .id_table = synaptics_i2c_id_table, 632 }; 633 634 module_i2c_driver(synaptics_i2c_driver); 635 636 MODULE_DESCRIPTION("Synaptics I2C touchpad driver"); 637 MODULE_AUTHOR("Mike Rapoport, Igor Grinberg, Compulab"); 638 MODULE_LICENSE("GPL"); 639 640