1/* 2 * ADS7846 based touchscreen and sensor driver 3 * 4 * Copyright (c) 2005 David Brownell 5 * Copyright (c) 2006 Nokia Corporation 6 * Various changes: Imre Deak <imre.deak@nokia.com> 7 * 8 * Using code from: 9 * - corgi_ts.c 10 * Copyright (C) 2004-2005 Richard Purdie 11 * - omap_ts.[hc], ads7846.h, ts_osk.c 12 * Copyright (C) 2002 MontaVista Software 13 * Copyright (C) 2004 Texas Instruments 14 * Copyright (C) 2005 Dirk Behme 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License version 2 as 18 * published by the Free Software Foundation. 19 */ 20#include <linux/types.h> 21#include <linux/hwmon.h> 22#include <linux/err.h> 23#include <linux/sched.h> 24#include <linux/delay.h> 25#include <linux/input.h> 26#include <linux/interrupt.h> 27#include <linux/slab.h> 28#include <linux/pm.h> 29#include <linux/of.h> 30#include <linux/of_gpio.h> 31#include <linux/of_device.h> 32#include <linux/gpio.h> 33#include <linux/spi/spi.h> 34#include <linux/spi/ads7846.h> 35#include <linux/regulator/consumer.h> 36#include <linux/module.h> 37#include <asm/irq.h> 38 39/* 40 * This code has been heavily tested on a Nokia 770, and lightly 41 * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). 42 * TSC2046 is just newer ads7846 silicon. 43 * Support for ads7843 tested on Atmel at91sam926x-EK. 44 * Support for ads7845 has only been stubbed in. 45 * Support for Analog Devices AD7873 and AD7843 tested. 46 * 47 * IRQ handling needs a workaround because of a shortcoming in handling 48 * edge triggered IRQs on some platforms like the OMAP1/2. These 49 * platforms don't handle the ARM lazy IRQ disabling properly, thus we 50 * have to maintain our own SW IRQ disabled status. This should be 51 * removed as soon as the affected platform's IRQ handling is fixed. 52 * 53 * App note sbaa036 talks in more detail about accurate sampling... 54 * that ought to help in situations like LCDs inducing noise (which 55 * can also be helped by using synch signals) and more generally. 56 * This driver tries to utilize the measures described in the app 57 * note. The strength of filtering can be set in the board-* specific 58 * files. 59 */ 60 61#define TS_POLL_DELAY 1 /* ms delay before the first sample */ 62#define TS_POLL_PERIOD 5 /* ms delay between samples */ 63 64/* this driver doesn't aim at the peak continuous sample rate */ 65#define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) 66 67struct ts_event { 68 /* 69 * For portability, we can't read 12 bit values using SPI (which 70 * would make the controller deliver them as native byte order u16 71 * with msbs zeroed). Instead, we read them as two 8-bit values, 72 * *** WHICH NEED BYTESWAPPING *** and range adjustment. 73 */ 74 u16 x; 75 u16 y; 76 u16 z1, z2; 77 bool ignore; 78 u8 x_buf[3]; 79 u8 y_buf[3]; 80}; 81 82/* 83 * We allocate this separately to avoid cache line sharing issues when 84 * driver is used with DMA-based SPI controllers (like atmel_spi) on 85 * systems where main memory is not DMA-coherent (most non-x86 boards). 86 */ 87struct ads7846_packet { 88 u8 read_x, read_y, read_z1, read_z2, pwrdown; 89 u16 dummy; /* for the pwrdown read */ 90 struct ts_event tc; 91 /* for ads7845 with mpc5121 psc spi we use 3-byte buffers */ 92 u8 read_x_cmd[3], read_y_cmd[3], pwrdown_cmd[3]; 93}; 94 95struct ads7846 { 96 struct input_dev *input; 97 char phys[32]; 98 char name[32]; 99 100 struct spi_device *spi; 101 struct regulator *reg; 102 103#if IS_ENABLED(CONFIG_HWMON) 104 struct device *hwmon; 105#endif 106 107 u16 model; 108 u16 vref_mv; 109 u16 vref_delay_usecs; 110 u16 x_plate_ohms; 111 u16 pressure_max; 112 113 bool swap_xy; 114 bool use_internal; 115 116 struct ads7846_packet *packet; 117 118 struct spi_transfer xfer[18]; 119 struct spi_message msg[5]; 120 int msg_count; 121 wait_queue_head_t wait; 122 123 bool pendown; 124 125 int read_cnt; 126 int read_rep; 127 int last_read; 128 129 u16 debounce_max; 130 u16 debounce_tol; 131 u16 debounce_rep; 132 133 u16 penirq_recheck_delay_usecs; 134 135 struct mutex lock; 136 bool stopped; /* P: lock */ 137 bool disabled; /* P: lock */ 138 bool suspended; /* P: lock */ 139 140 int (*filter)(void *data, int data_idx, int *val); 141 void *filter_data; 142 void (*filter_cleanup)(void *data); 143 int (*get_pendown_state)(void); 144 int gpio_pendown; 145 146 void (*wait_for_sync)(void); 147}; 148 149/* leave chip selected when we're done, for quicker re-select? */ 150#if 0 151#define CS_CHANGE(xfer) ((xfer).cs_change = 1) 152#else 153#define CS_CHANGE(xfer) ((xfer).cs_change = 0) 154#endif 155 156/*--------------------------------------------------------------------------*/ 157 158/* The ADS7846 has touchscreen and other sensors. 159 * Earlier ads784x chips are somewhat compatible. 160 */ 161#define ADS_START (1 << 7) 162#define ADS_A2A1A0_d_y (1 << 4) /* differential */ 163#define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ 164#define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ 165#define ADS_A2A1A0_d_x (5 << 4) /* differential */ 166#define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ 167#define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ 168#define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ 169#define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ 170#define ADS_8_BIT (1 << 3) 171#define ADS_12_BIT (0 << 3) 172#define ADS_SER (1 << 2) /* non-differential */ 173#define ADS_DFR (0 << 2) /* differential */ 174#define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */ 175#define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ 176#define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ 177#define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ 178 179#define MAX_12BIT ((1<<12)-1) 180 181/* leave ADC powered up (disables penirq) between differential samples */ 182#define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ 183 | ADS_12_BIT | ADS_DFR | \ 184 (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) 185 186#define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) 187#define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) 188#define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) 189 190#define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) 191#define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ 192 193/* single-ended samples need to first power up reference voltage; 194 * we leave both ADC and VREF powered 195 */ 196#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ 197 | ADS_12_BIT | ADS_SER) 198 199#define REF_ON (READ_12BIT_DFR(x, 1, 1)) 200#define REF_OFF (READ_12BIT_DFR(y, 0, 0)) 201 202/* Must be called with ts->lock held */ 203static void ads7846_stop(struct ads7846 *ts) 204{ 205 if (!ts->disabled && !ts->suspended) { 206 /* Signal IRQ thread to stop polling and disable the handler. */ 207 ts->stopped = true; 208 mb(); 209 wake_up(&ts->wait); 210 disable_irq(ts->spi->irq); 211 } 212} 213 214/* Must be called with ts->lock held */ 215static void ads7846_restart(struct ads7846 *ts) 216{ 217 if (!ts->disabled && !ts->suspended) { 218 /* Tell IRQ thread that it may poll the device. */ 219 ts->stopped = false; 220 mb(); 221 enable_irq(ts->spi->irq); 222 } 223} 224 225/* Must be called with ts->lock held */ 226static void __ads7846_disable(struct ads7846 *ts) 227{ 228 ads7846_stop(ts); 229 regulator_disable(ts->reg); 230 231 /* 232 * We know the chip's in low power mode since we always 233 * leave it that way after every request 234 */ 235} 236 237/* Must be called with ts->lock held */ 238static void __ads7846_enable(struct ads7846 *ts) 239{ 240 int error; 241 242 error = regulator_enable(ts->reg); 243 if (error != 0) 244 dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error); 245 246 ads7846_restart(ts); 247} 248 249static void ads7846_disable(struct ads7846 *ts) 250{ 251 mutex_lock(&ts->lock); 252 253 if (!ts->disabled) { 254 255 if (!ts->suspended) 256 __ads7846_disable(ts); 257 258 ts->disabled = true; 259 } 260 261 mutex_unlock(&ts->lock); 262} 263 264static void ads7846_enable(struct ads7846 *ts) 265{ 266 mutex_lock(&ts->lock); 267 268 if (ts->disabled) { 269 270 ts->disabled = false; 271 272 if (!ts->suspended) 273 __ads7846_enable(ts); 274 } 275 276 mutex_unlock(&ts->lock); 277} 278 279/*--------------------------------------------------------------------------*/ 280 281/* 282 * Non-touchscreen sensors only use single-ended conversions. 283 * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; 284 * ads7846 lets that pin be unconnected, to use internal vREF. 285 */ 286 287struct ser_req { 288 u8 ref_on; 289 u8 command; 290 u8 ref_off; 291 u16 scratch; 292 struct spi_message msg; 293 struct spi_transfer xfer[6]; 294 /* 295 * DMA (thus cache coherency maintenance) requires the 296 * transfer buffers to live in their own cache lines. 297 */ 298 __be16 sample ____cacheline_aligned; 299}; 300 301struct ads7845_ser_req { 302 u8 command[3]; 303 struct spi_message msg; 304 struct spi_transfer xfer[2]; 305 /* 306 * DMA (thus cache coherency maintenance) requires the 307 * transfer buffers to live in their own cache lines. 308 */ 309 u8 sample[3] ____cacheline_aligned; 310}; 311 312static int ads7846_read12_ser(struct device *dev, unsigned command) 313{ 314 struct spi_device *spi = to_spi_device(dev); 315 struct ads7846 *ts = dev_get_drvdata(dev); 316 struct ser_req *req; 317 int status; 318 319 req = kzalloc(sizeof *req, GFP_KERNEL); 320 if (!req) 321 return -ENOMEM; 322 323 spi_message_init(&req->msg); 324 325 /* maybe turn on internal vREF, and let it settle */ 326 if (ts->use_internal) { 327 req->ref_on = REF_ON; 328 req->xfer[0].tx_buf = &req->ref_on; 329 req->xfer[0].len = 1; 330 spi_message_add_tail(&req->xfer[0], &req->msg); 331 332 req->xfer[1].rx_buf = &req->scratch; 333 req->xfer[1].len = 2; 334 335 /* for 1uF, settle for 800 usec; no cap, 100 usec. */ 336 req->xfer[1].delay_usecs = ts->vref_delay_usecs; 337 spi_message_add_tail(&req->xfer[1], &req->msg); 338 339 /* Enable reference voltage */ 340 command |= ADS_PD10_REF_ON; 341 } 342 343 /* Enable ADC in every case */ 344 command |= ADS_PD10_ADC_ON; 345 346 /* take sample */ 347 req->command = (u8) command; 348 req->xfer[2].tx_buf = &req->command; 349 req->xfer[2].len = 1; 350 spi_message_add_tail(&req->xfer[2], &req->msg); 351 352 req->xfer[3].rx_buf = &req->sample; 353 req->xfer[3].len = 2; 354 spi_message_add_tail(&req->xfer[3], &req->msg); 355 356 /* REVISIT: take a few more samples, and compare ... */ 357 358 /* converter in low power mode & enable PENIRQ */ 359 req->ref_off = PWRDOWN; 360 req->xfer[4].tx_buf = &req->ref_off; 361 req->xfer[4].len = 1; 362 spi_message_add_tail(&req->xfer[4], &req->msg); 363 364 req->xfer[5].rx_buf = &req->scratch; 365 req->xfer[5].len = 2; 366 CS_CHANGE(req->xfer[5]); 367 spi_message_add_tail(&req->xfer[5], &req->msg); 368 369 mutex_lock(&ts->lock); 370 ads7846_stop(ts); 371 status = spi_sync(spi, &req->msg); 372 ads7846_restart(ts); 373 mutex_unlock(&ts->lock); 374 375 if (status == 0) { 376 /* on-wire is a must-ignore bit, a BE12 value, then padding */ 377 status = be16_to_cpu(req->sample); 378 status = status >> 3; 379 status &= 0x0fff; 380 } 381 382 kfree(req); 383 return status; 384} 385 386static int ads7845_read12_ser(struct device *dev, unsigned command) 387{ 388 struct spi_device *spi = to_spi_device(dev); 389 struct ads7846 *ts = dev_get_drvdata(dev); 390 struct ads7845_ser_req *req; 391 int status; 392 393 req = kzalloc(sizeof *req, GFP_KERNEL); 394 if (!req) 395 return -ENOMEM; 396 397 spi_message_init(&req->msg); 398 399 req->command[0] = (u8) command; 400 req->xfer[0].tx_buf = req->command; 401 req->xfer[0].rx_buf = req->sample; 402 req->xfer[0].len = 3; 403 spi_message_add_tail(&req->xfer[0], &req->msg); 404 405 mutex_lock(&ts->lock); 406 ads7846_stop(ts); 407 status = spi_sync(spi, &req->msg); 408 ads7846_restart(ts); 409 mutex_unlock(&ts->lock); 410 411 if (status == 0) { 412 /* BE12 value, then padding */ 413 status = be16_to_cpu(*((u16 *)&req->sample[1])); 414 status = status >> 3; 415 status &= 0x0fff; 416 } 417 418 kfree(req); 419 return status; 420} 421 422#if IS_ENABLED(CONFIG_HWMON) 423 424#define SHOW(name, var, adjust) static ssize_t \ 425name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ 426{ \ 427 struct ads7846 *ts = dev_get_drvdata(dev); \ 428 ssize_t v = ads7846_read12_ser(&ts->spi->dev, \ 429 READ_12BIT_SER(var)); \ 430 if (v < 0) \ 431 return v; \ 432 return sprintf(buf, "%u\n", adjust(ts, v)); \ 433} \ 434static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); 435 436 437/* Sysfs conventions report temperatures in millidegrees Celsius. 438 * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high 439 * accuracy scheme without calibration data. For now we won't try either; 440 * userspace sees raw sensor values, and must scale/calibrate appropriately. 441 */ 442static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) 443{ 444 return v; 445} 446 447SHOW(temp0, temp0, null_adjust) /* temp1_input */ 448SHOW(temp1, temp1, null_adjust) /* temp2_input */ 449 450 451/* sysfs conventions report voltages in millivolts. We can convert voltages 452 * if we know vREF. userspace may need to scale vAUX to match the board's 453 * external resistors; we assume that vBATT only uses the internal ones. 454 */ 455static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) 456{ 457 unsigned retval = v; 458 459 /* external resistors may scale vAUX into 0..vREF */ 460 retval *= ts->vref_mv; 461 retval = retval >> 12; 462 463 return retval; 464} 465 466static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) 467{ 468 unsigned retval = vaux_adjust(ts, v); 469 470 /* ads7846 has a resistor ladder to scale this signal down */ 471 if (ts->model == 7846) 472 retval *= 4; 473 474 return retval; 475} 476 477SHOW(in0_input, vaux, vaux_adjust) 478SHOW(in1_input, vbatt, vbatt_adjust) 479 480static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr, 481 int index) 482{ 483 struct device *dev = container_of(kobj, struct device, kobj); 484 struct ads7846 *ts = dev_get_drvdata(dev); 485 486 if (ts->model == 7843 && index < 2) /* in0, in1 */ 487 return 0; 488 if (ts->model == 7845 && index != 2) /* in0 */ 489 return 0; 490 491 return attr->mode; 492} 493 494static struct attribute *ads7846_attributes[] = { 495 &dev_attr_temp0.attr, /* 0 */ 496 &dev_attr_temp1.attr, /* 1 */ 497 &dev_attr_in0_input.attr, /* 2 */ 498 &dev_attr_in1_input.attr, /* 3 */ 499 NULL, 500}; 501 502static struct attribute_group ads7846_attr_group = { 503 .attrs = ads7846_attributes, 504 .is_visible = ads7846_is_visible, 505}; 506__ATTRIBUTE_GROUPS(ads7846_attr); 507 508static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) 509{ 510 /* hwmon sensors need a reference voltage */ 511 switch (ts->model) { 512 case 7846: 513 if (!ts->vref_mv) { 514 dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); 515 ts->vref_mv = 2500; 516 ts->use_internal = true; 517 } 518 break; 519 case 7845: 520 case 7843: 521 if (!ts->vref_mv) { 522 dev_warn(&spi->dev, 523 "external vREF for ADS%d not specified\n", 524 ts->model); 525 return 0; 526 } 527 break; 528 } 529 530 ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias, 531 ts, ads7846_attr_groups); 532 if (IS_ERR(ts->hwmon)) 533 return PTR_ERR(ts->hwmon); 534 535 return 0; 536} 537 538static void ads784x_hwmon_unregister(struct spi_device *spi, 539 struct ads7846 *ts) 540{ 541 if (ts->hwmon) 542 hwmon_device_unregister(ts->hwmon); 543} 544 545#else 546static inline int ads784x_hwmon_register(struct spi_device *spi, 547 struct ads7846 *ts) 548{ 549 return 0; 550} 551 552static inline void ads784x_hwmon_unregister(struct spi_device *spi, 553 struct ads7846 *ts) 554{ 555} 556#endif 557 558static ssize_t ads7846_pen_down_show(struct device *dev, 559 struct device_attribute *attr, char *buf) 560{ 561 struct ads7846 *ts = dev_get_drvdata(dev); 562 563 return sprintf(buf, "%u\n", ts->pendown); 564} 565 566static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); 567 568static ssize_t ads7846_disable_show(struct device *dev, 569 struct device_attribute *attr, char *buf) 570{ 571 struct ads7846 *ts = dev_get_drvdata(dev); 572 573 return sprintf(buf, "%u\n", ts->disabled); 574} 575 576static ssize_t ads7846_disable_store(struct device *dev, 577 struct device_attribute *attr, 578 const char *buf, size_t count) 579{ 580 struct ads7846 *ts = dev_get_drvdata(dev); 581 unsigned int i; 582 int err; 583 584 err = kstrtouint(buf, 10, &i); 585 if (err) 586 return err; 587 588 if (i) 589 ads7846_disable(ts); 590 else 591 ads7846_enable(ts); 592 593 return count; 594} 595 596static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); 597 598static struct attribute *ads784x_attributes[] = { 599 &dev_attr_pen_down.attr, 600 &dev_attr_disable.attr, 601 NULL, 602}; 603 604static struct attribute_group ads784x_attr_group = { 605 .attrs = ads784x_attributes, 606}; 607 608/*--------------------------------------------------------------------------*/ 609 610static int get_pendown_state(struct ads7846 *ts) 611{ 612 if (ts->get_pendown_state) 613 return ts->get_pendown_state(); 614 615 return !gpio_get_value(ts->gpio_pendown); 616} 617 618static void null_wait_for_sync(void) 619{ 620} 621 622static int ads7846_debounce_filter(void *ads, int data_idx, int *val) 623{ 624 struct ads7846 *ts = ads; 625 626 if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { 627 /* Start over collecting consistent readings. */ 628 ts->read_rep = 0; 629 /* 630 * Repeat it, if this was the first read or the read 631 * wasn't consistent enough. 632 */ 633 if (ts->read_cnt < ts->debounce_max) { 634 ts->last_read = *val; 635 ts->read_cnt++; 636 return ADS7846_FILTER_REPEAT; 637 } else { 638 /* 639 * Maximum number of debouncing reached and still 640 * not enough number of consistent readings. Abort 641 * the whole sample, repeat it in the next sampling 642 * period. 643 */ 644 ts->read_cnt = 0; 645 return ADS7846_FILTER_IGNORE; 646 } 647 } else { 648 if (++ts->read_rep > ts->debounce_rep) { 649 /* 650 * Got a good reading for this coordinate, 651 * go for the next one. 652 */ 653 ts->read_cnt = 0; 654 ts->read_rep = 0; 655 return ADS7846_FILTER_OK; 656 } else { 657 /* Read more values that are consistent. */ 658 ts->read_cnt++; 659 return ADS7846_FILTER_REPEAT; 660 } 661 } 662} 663 664static int ads7846_no_filter(void *ads, int data_idx, int *val) 665{ 666 return ADS7846_FILTER_OK; 667} 668 669static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m) 670{ 671 struct spi_transfer *t = 672 list_entry(m->transfers.prev, struct spi_transfer, transfer_list); 673 674 if (ts->model == 7845) { 675 return be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3; 676 } else { 677 /* 678 * adjust: on-wire is a must-ignore bit, a BE12 value, then 679 * padding; built from two 8 bit values written msb-first. 680 */ 681 return be16_to_cpup((__be16 *)t->rx_buf) >> 3; 682 } 683} 684 685static void ads7846_update_value(struct spi_message *m, int val) 686{ 687 struct spi_transfer *t = 688 list_entry(m->transfers.prev, struct spi_transfer, transfer_list); 689 690 *(u16 *)t->rx_buf = val; 691} 692 693static void ads7846_read_state(struct ads7846 *ts) 694{ 695 struct ads7846_packet *packet = ts->packet; 696 struct spi_message *m; 697 int msg_idx = 0; 698 int val; 699 int action; 700 int error; 701 702 while (msg_idx < ts->msg_count) { 703 704 ts->wait_for_sync(); 705 706 m = &ts->msg[msg_idx]; 707 error = spi_sync(ts->spi, m); 708 if (error) { 709 dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); 710 packet->tc.ignore = true; 711 return; 712 } 713 714 /* 715 * Last message is power down request, no need to convert 716 * or filter the value. 717 */ 718 if (msg_idx < ts->msg_count - 1) { 719 720 val = ads7846_get_value(ts, m); 721 722 action = ts->filter(ts->filter_data, msg_idx, &val); 723 switch (action) { 724 case ADS7846_FILTER_REPEAT: 725 continue; 726 727 case ADS7846_FILTER_IGNORE: 728 packet->tc.ignore = true; 729 msg_idx = ts->msg_count - 1; 730 continue; 731 732 case ADS7846_FILTER_OK: 733 ads7846_update_value(m, val); 734 packet->tc.ignore = false; 735 msg_idx++; 736 break; 737 738 default: 739 BUG(); 740 } 741 } else { 742 msg_idx++; 743 } 744 } 745} 746 747static void ads7846_report_state(struct ads7846 *ts) 748{ 749 struct ads7846_packet *packet = ts->packet; 750 unsigned int Rt; 751 u16 x, y, z1, z2; 752 753 /* 754 * ads7846_get_value() does in-place conversion (including byte swap) 755 * from on-the-wire format as part of debouncing to get stable 756 * readings. 757 */ 758 if (ts->model == 7845) { 759 x = *(u16 *)packet->tc.x_buf; 760 y = *(u16 *)packet->tc.y_buf; 761 z1 = 0; 762 z2 = 0; 763 } else { 764 x = packet->tc.x; 765 y = packet->tc.y; 766 z1 = packet->tc.z1; 767 z2 = packet->tc.z2; 768 } 769 770 /* range filtering */ 771 if (x == MAX_12BIT) 772 x = 0; 773 774 if (ts->model == 7843) { 775 Rt = ts->pressure_max / 2; 776 } else if (ts->model == 7845) { 777 if (get_pendown_state(ts)) 778 Rt = ts->pressure_max / 2; 779 else 780 Rt = 0; 781 dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt); 782 } else if (likely(x && z1)) { 783 /* compute touch pressure resistance using equation #2 */ 784 Rt = z2; 785 Rt -= z1; 786 Rt *= x; 787 Rt *= ts->x_plate_ohms; 788 Rt /= z1; 789 Rt = (Rt + 2047) >> 12; 790 } else { 791 Rt = 0; 792 } 793 794 /* 795 * Sample found inconsistent by debouncing or pressure is beyond 796 * the maximum. Don't report it to user space, repeat at least 797 * once more the measurement 798 */ 799 if (packet->tc.ignore || Rt > ts->pressure_max) { 800 dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", 801 packet->tc.ignore, Rt); 802 return; 803 } 804 805 /* 806 * Maybe check the pendown state before reporting. This discards 807 * false readings when the pen is lifted. 808 */ 809 if (ts->penirq_recheck_delay_usecs) { 810 udelay(ts->penirq_recheck_delay_usecs); 811 if (!get_pendown_state(ts)) 812 Rt = 0; 813 } 814 815 /* 816 * NOTE: We can't rely on the pressure to determine the pen down 817 * state, even this controller has a pressure sensor. The pressure 818 * value can fluctuate for quite a while after lifting the pen and 819 * in some cases may not even settle at the expected value. 820 * 821 * The only safe way to check for the pen up condition is in the 822 * timer by reading the pen signal state (it's a GPIO _and_ IRQ). 823 */ 824 if (Rt) { 825 struct input_dev *input = ts->input; 826 827 if (ts->swap_xy) 828 swap(x, y); 829 830 if (!ts->pendown) { 831 input_report_key(input, BTN_TOUCH, 1); 832 ts->pendown = true; 833 dev_vdbg(&ts->spi->dev, "DOWN\n"); 834 } 835 836 input_report_abs(input, ABS_X, x); 837 input_report_abs(input, ABS_Y, y); 838 input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); 839 840 input_sync(input); 841 dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); 842 } 843} 844 845static irqreturn_t ads7846_hard_irq(int irq, void *handle) 846{ 847 struct ads7846 *ts = handle; 848 849 return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; 850} 851 852 853static irqreturn_t ads7846_irq(int irq, void *handle) 854{ 855 struct ads7846 *ts = handle; 856 857 /* Start with a small delay before checking pendown state */ 858 msleep(TS_POLL_DELAY); 859 860 while (!ts->stopped && get_pendown_state(ts)) { 861 862 /* pen is down, continue with the measurement */ 863 ads7846_read_state(ts); 864 865 if (!ts->stopped) 866 ads7846_report_state(ts); 867 868 wait_event_timeout(ts->wait, ts->stopped, 869 msecs_to_jiffies(TS_POLL_PERIOD)); 870 } 871 872 if (ts->pendown) { 873 struct input_dev *input = ts->input; 874 875 input_report_key(input, BTN_TOUCH, 0); 876 input_report_abs(input, ABS_PRESSURE, 0); 877 input_sync(input); 878 879 ts->pendown = false; 880 dev_vdbg(&ts->spi->dev, "UP\n"); 881 } 882 883 return IRQ_HANDLED; 884} 885 886static int __maybe_unused ads7846_suspend(struct device *dev) 887{ 888 struct ads7846 *ts = dev_get_drvdata(dev); 889 890 mutex_lock(&ts->lock); 891 892 if (!ts->suspended) { 893 894 if (!ts->disabled) 895 __ads7846_disable(ts); 896 897 if (device_may_wakeup(&ts->spi->dev)) 898 enable_irq_wake(ts->spi->irq); 899 900 ts->suspended = true; 901 } 902 903 mutex_unlock(&ts->lock); 904 905 return 0; 906} 907 908static int __maybe_unused ads7846_resume(struct device *dev) 909{ 910 struct ads7846 *ts = dev_get_drvdata(dev); 911 912 mutex_lock(&ts->lock); 913 914 if (ts->suspended) { 915 916 ts->suspended = false; 917 918 if (device_may_wakeup(&ts->spi->dev)) 919 disable_irq_wake(ts->spi->irq); 920 921 if (!ts->disabled) 922 __ads7846_enable(ts); 923 } 924 925 mutex_unlock(&ts->lock); 926 927 return 0; 928} 929 930static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume); 931 932static int ads7846_setup_pendown(struct spi_device *spi, 933 struct ads7846 *ts, 934 const struct ads7846_platform_data *pdata) 935{ 936 int err; 937 938 /* 939 * REVISIT when the irq can be triggered active-low, or if for some 940 * reason the touchscreen isn't hooked up, we don't need to access 941 * the pendown state. 942 */ 943 944 if (pdata->get_pendown_state) { 945 ts->get_pendown_state = pdata->get_pendown_state; 946 } else if (gpio_is_valid(pdata->gpio_pendown)) { 947 948 err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN, 949 "ads7846_pendown"); 950 if (err) { 951 dev_err(&spi->dev, 952 "failed to request/setup pendown GPIO%d: %d\n", 953 pdata->gpio_pendown, err); 954 return err; 955 } 956 957 ts->gpio_pendown = pdata->gpio_pendown; 958 959 if (pdata->gpio_pendown_debounce) 960 gpio_set_debounce(pdata->gpio_pendown, 961 pdata->gpio_pendown_debounce); 962 } else { 963 dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); 964 return -EINVAL; 965 } 966 967 return 0; 968} 969 970/* 971 * Set up the transfers to read touchscreen state; this assumes we 972 * use formula #2 for pressure, not #3. 973 */ 974static void ads7846_setup_spi_msg(struct ads7846 *ts, 975 const struct ads7846_platform_data *pdata) 976{ 977 struct spi_message *m = &ts->msg[0]; 978 struct spi_transfer *x = ts->xfer; 979 struct ads7846_packet *packet = ts->packet; 980 int vref = pdata->keep_vref_on; 981 982 if (ts->model == 7873) { 983 /* 984 * The AD7873 is almost identical to the ADS7846 985 * keep VREF off during differential/ratiometric 986 * conversion modes. 987 */ 988 ts->model = 7846; 989 vref = 0; 990 } 991 992 ts->msg_count = 1; 993 spi_message_init(m); 994 m->context = ts; 995 996 if (ts->model == 7845) { 997 packet->read_y_cmd[0] = READ_Y(vref); 998 packet->read_y_cmd[1] = 0; 999 packet->read_y_cmd[2] = 0; 1000 x->tx_buf = &packet->read_y_cmd[0]; 1001 x->rx_buf = &packet->tc.y_buf[0]; 1002 x->len = 3; 1003 spi_message_add_tail(x, m); 1004 } else { 1005 /* y- still on; turn on only y+ (and ADC) */ 1006 packet->read_y = READ_Y(vref); 1007 x->tx_buf = &packet->read_y; 1008 x->len = 1; 1009 spi_message_add_tail(x, m); 1010 1011 x++; 1012 x->rx_buf = &packet->tc.y; 1013 x->len = 2; 1014 spi_message_add_tail(x, m); 1015 } 1016 1017 /* 1018 * The first sample after switching drivers can be low quality; 1019 * optionally discard it, using a second one after the signals 1020 * have had enough time to stabilize. 1021 */ 1022 if (pdata->settle_delay_usecs) { 1023 x->delay_usecs = pdata->settle_delay_usecs; 1024 1025 x++; 1026 x->tx_buf = &packet->read_y; 1027 x->len = 1; 1028 spi_message_add_tail(x, m); 1029 1030 x++; 1031 x->rx_buf = &packet->tc.y; 1032 x->len = 2; 1033 spi_message_add_tail(x, m); 1034 } 1035 1036 ts->msg_count++; 1037 m++; 1038 spi_message_init(m); 1039 m->context = ts; 1040 1041 if (ts->model == 7845) { 1042 x++; 1043 packet->read_x_cmd[0] = READ_X(vref); 1044 packet->read_x_cmd[1] = 0; 1045 packet->read_x_cmd[2] = 0; 1046 x->tx_buf = &packet->read_x_cmd[0]; 1047 x->rx_buf = &packet->tc.x_buf[0]; 1048 x->len = 3; 1049 spi_message_add_tail(x, m); 1050 } else { 1051 /* turn y- off, x+ on, then leave in lowpower */ 1052 x++; 1053 packet->read_x = READ_X(vref); 1054 x->tx_buf = &packet->read_x; 1055 x->len = 1; 1056 spi_message_add_tail(x, m); 1057 1058 x++; 1059 x->rx_buf = &packet->tc.x; 1060 x->len = 2; 1061 spi_message_add_tail(x, m); 1062 } 1063 1064 /* ... maybe discard first sample ... */ 1065 if (pdata->settle_delay_usecs) { 1066 x->delay_usecs = pdata->settle_delay_usecs; 1067 1068 x++; 1069 x->tx_buf = &packet->read_x; 1070 x->len = 1; 1071 spi_message_add_tail(x, m); 1072 1073 x++; 1074 x->rx_buf = &packet->tc.x; 1075 x->len = 2; 1076 spi_message_add_tail(x, m); 1077 } 1078 1079 /* turn y+ off, x- on; we'll use formula #2 */ 1080 if (ts->model == 7846) { 1081 ts->msg_count++; 1082 m++; 1083 spi_message_init(m); 1084 m->context = ts; 1085 1086 x++; 1087 packet->read_z1 = READ_Z1(vref); 1088 x->tx_buf = &packet->read_z1; 1089 x->len = 1; 1090 spi_message_add_tail(x, m); 1091 1092 x++; 1093 x->rx_buf = &packet->tc.z1; 1094 x->len = 2; 1095 spi_message_add_tail(x, m); 1096 1097 /* ... maybe discard first sample ... */ 1098 if (pdata->settle_delay_usecs) { 1099 x->delay_usecs = pdata->settle_delay_usecs; 1100 1101 x++; 1102 x->tx_buf = &packet->read_z1; 1103 x->len = 1; 1104 spi_message_add_tail(x, m); 1105 1106 x++; 1107 x->rx_buf = &packet->tc.z1; 1108 x->len = 2; 1109 spi_message_add_tail(x, m); 1110 } 1111 1112 ts->msg_count++; 1113 m++; 1114 spi_message_init(m); 1115 m->context = ts; 1116 1117 x++; 1118 packet->read_z2 = READ_Z2(vref); 1119 x->tx_buf = &packet->read_z2; 1120 x->len = 1; 1121 spi_message_add_tail(x, m); 1122 1123 x++; 1124 x->rx_buf = &packet->tc.z2; 1125 x->len = 2; 1126 spi_message_add_tail(x, m); 1127 1128 /* ... maybe discard first sample ... */ 1129 if (pdata->settle_delay_usecs) { 1130 x->delay_usecs = pdata->settle_delay_usecs; 1131 1132 x++; 1133 x->tx_buf = &packet->read_z2; 1134 x->len = 1; 1135 spi_message_add_tail(x, m); 1136 1137 x++; 1138 x->rx_buf = &packet->tc.z2; 1139 x->len = 2; 1140 spi_message_add_tail(x, m); 1141 } 1142 } 1143 1144 /* power down */ 1145 ts->msg_count++; 1146 m++; 1147 spi_message_init(m); 1148 m->context = ts; 1149 1150 if (ts->model == 7845) { 1151 x++; 1152 packet->pwrdown_cmd[0] = PWRDOWN; 1153 packet->pwrdown_cmd[1] = 0; 1154 packet->pwrdown_cmd[2] = 0; 1155 x->tx_buf = &packet->pwrdown_cmd[0]; 1156 x->len = 3; 1157 } else { 1158 x++; 1159 packet->pwrdown = PWRDOWN; 1160 x->tx_buf = &packet->pwrdown; 1161 x->len = 1; 1162 spi_message_add_tail(x, m); 1163 1164 x++; 1165 x->rx_buf = &packet->dummy; 1166 x->len = 2; 1167 } 1168 1169 CS_CHANGE(*x); 1170 spi_message_add_tail(x, m); 1171} 1172 1173#ifdef CONFIG_OF 1174static const struct of_device_id ads7846_dt_ids[] = { 1175 { .compatible = "ti,tsc2046", .data = (void *) 7846 }, 1176 { .compatible = "ti,ads7843", .data = (void *) 7843 }, 1177 { .compatible = "ti,ads7845", .data = (void *) 7845 }, 1178 { .compatible = "ti,ads7846", .data = (void *) 7846 }, 1179 { .compatible = "ti,ads7873", .data = (void *) 7873 }, 1180 { } 1181}; 1182MODULE_DEVICE_TABLE(of, ads7846_dt_ids); 1183 1184static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) 1185{ 1186 struct ads7846_platform_data *pdata; 1187 struct device_node *node = dev->of_node; 1188 const struct of_device_id *match; 1189 1190 if (!node) { 1191 dev_err(dev, "Device does not have associated DT data\n"); 1192 return ERR_PTR(-EINVAL); 1193 } 1194 1195 match = of_match_device(ads7846_dt_ids, dev); 1196 if (!match) { 1197 dev_err(dev, "Unknown device model\n"); 1198 return ERR_PTR(-EINVAL); 1199 } 1200 1201 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 1202 if (!pdata) 1203 return ERR_PTR(-ENOMEM); 1204 1205 pdata->model = (unsigned long)match->data; 1206 1207 of_property_read_u16(node, "ti,vref-delay-usecs", 1208 &pdata->vref_delay_usecs); 1209 of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv); 1210 pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on"); 1211 1212 pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy"); 1213 1214 of_property_read_u16(node, "ti,settle-delay-usec", 1215 &pdata->settle_delay_usecs); 1216 of_property_read_u16(node, "ti,penirq-recheck-delay-usecs", 1217 &pdata->penirq_recheck_delay_usecs); 1218 1219 of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms); 1220 of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms); 1221 1222 of_property_read_u16(node, "ti,x-min", &pdata->x_min); 1223 of_property_read_u16(node, "ti,y-min", &pdata->y_min); 1224 of_property_read_u16(node, "ti,x-max", &pdata->x_max); 1225 of_property_read_u16(node, "ti,y-max", &pdata->y_max); 1226 1227 of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min); 1228 of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max); 1229 1230 of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max); 1231 of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol); 1232 of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep); 1233 1234 of_property_read_u32(node, "ti,pendown-gpio-debounce", 1235 &pdata->gpio_pendown_debounce); 1236 1237 pdata->wakeup = of_property_read_bool(node, "linux,wakeup"); 1238 1239 pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0); 1240 1241 return pdata; 1242} 1243#else 1244static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) 1245{ 1246 dev_err(dev, "no platform data defined\n"); 1247 return ERR_PTR(-EINVAL); 1248} 1249#endif 1250 1251static int ads7846_probe(struct spi_device *spi) 1252{ 1253 const struct ads7846_platform_data *pdata; 1254 struct ads7846 *ts; 1255 struct ads7846_packet *packet; 1256 struct input_dev *input_dev; 1257 unsigned long irq_flags; 1258 int err; 1259 1260 if (!spi->irq) { 1261 dev_dbg(&spi->dev, "no IRQ?\n"); 1262 return -EINVAL; 1263 } 1264 1265 /* don't exceed max specified sample rate */ 1266 if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { 1267 dev_err(&spi->dev, "f(sample) %d KHz?\n", 1268 (spi->max_speed_hz/SAMPLE_BITS)/1000); 1269 return -EINVAL; 1270 } 1271 1272 /* 1273 * We'd set TX word size 8 bits and RX word size to 13 bits ... except 1274 * that even if the hardware can do that, the SPI controller driver 1275 * may not. So we stick to very-portable 8 bit words, both RX and TX. 1276 */ 1277 spi->bits_per_word = 8; 1278 spi->mode = SPI_MODE_0; 1279 err = spi_setup(spi); 1280 if (err < 0) 1281 return err; 1282 1283 ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); 1284 packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); 1285 input_dev = input_allocate_device(); 1286 if (!ts || !packet || !input_dev) { 1287 err = -ENOMEM; 1288 goto err_free_mem; 1289 } 1290 1291 spi_set_drvdata(spi, ts); 1292 1293 ts->packet = packet; 1294 ts->spi = spi; 1295 ts->input = input_dev; 1296 1297 mutex_init(&ts->lock); 1298 init_waitqueue_head(&ts->wait); 1299 1300 pdata = dev_get_platdata(&spi->dev); 1301 if (!pdata) { 1302 pdata = ads7846_probe_dt(&spi->dev); 1303 if (IS_ERR(pdata)) { 1304 err = PTR_ERR(pdata); 1305 goto err_free_mem; 1306 } 1307 } 1308 1309 ts->model = pdata->model ? : 7846; 1310 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; 1311 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; 1312 ts->pressure_max = pdata->pressure_max ? : ~0; 1313 1314 ts->vref_mv = pdata->vref_mv; 1315 ts->swap_xy = pdata->swap_xy; 1316 1317 if (pdata->filter != NULL) { 1318 if (pdata->filter_init != NULL) { 1319 err = pdata->filter_init(pdata, &ts->filter_data); 1320 if (err < 0) 1321 goto err_free_mem; 1322 } 1323 ts->filter = pdata->filter; 1324 ts->filter_cleanup = pdata->filter_cleanup; 1325 } else if (pdata->debounce_max) { 1326 ts->debounce_max = pdata->debounce_max; 1327 if (ts->debounce_max < 2) 1328 ts->debounce_max = 2; 1329 ts->debounce_tol = pdata->debounce_tol; 1330 ts->debounce_rep = pdata->debounce_rep; 1331 ts->filter = ads7846_debounce_filter; 1332 ts->filter_data = ts; 1333 } else { 1334 ts->filter = ads7846_no_filter; 1335 } 1336 1337 err = ads7846_setup_pendown(spi, ts, pdata); 1338 if (err) 1339 goto err_cleanup_filter; 1340 1341 if (pdata->penirq_recheck_delay_usecs) 1342 ts->penirq_recheck_delay_usecs = 1343 pdata->penirq_recheck_delay_usecs; 1344 1345 ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; 1346 1347 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); 1348 snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); 1349 1350 input_dev->name = ts->name; 1351 input_dev->phys = ts->phys; 1352 input_dev->dev.parent = &spi->dev; 1353 1354 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 1355 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 1356 input_set_abs_params(input_dev, ABS_X, 1357 pdata->x_min ? : 0, 1358 pdata->x_max ? : MAX_12BIT, 1359 0, 0); 1360 input_set_abs_params(input_dev, ABS_Y, 1361 pdata->y_min ? : 0, 1362 pdata->y_max ? : MAX_12BIT, 1363 0, 0); 1364 input_set_abs_params(input_dev, ABS_PRESSURE, 1365 pdata->pressure_min, pdata->pressure_max, 0, 0); 1366 1367 ads7846_setup_spi_msg(ts, pdata); 1368 1369 ts->reg = regulator_get(&spi->dev, "vcc"); 1370 if (IS_ERR(ts->reg)) { 1371 err = PTR_ERR(ts->reg); 1372 dev_err(&spi->dev, "unable to get regulator: %d\n", err); 1373 goto err_free_gpio; 1374 } 1375 1376 err = regulator_enable(ts->reg); 1377 if (err) { 1378 dev_err(&spi->dev, "unable to enable regulator: %d\n", err); 1379 goto err_put_regulator; 1380 } 1381 1382 irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; 1383 irq_flags |= IRQF_ONESHOT; 1384 1385 err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, 1386 irq_flags, spi->dev.driver->name, ts); 1387 if (err && !pdata->irq_flags) { 1388 dev_info(&spi->dev, 1389 "trying pin change workaround on irq %d\n", spi->irq); 1390 irq_flags |= IRQF_TRIGGER_RISING; 1391 err = request_threaded_irq(spi->irq, 1392 ads7846_hard_irq, ads7846_irq, 1393 irq_flags, spi->dev.driver->name, ts); 1394 } 1395 1396 if (err) { 1397 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); 1398 goto err_disable_regulator; 1399 } 1400 1401 err = ads784x_hwmon_register(spi, ts); 1402 if (err) 1403 goto err_free_irq; 1404 1405 dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); 1406 1407 /* 1408 * Take a first sample, leaving nPENIRQ active and vREF off; avoid 1409 * the touchscreen, in case it's not connected. 1410 */ 1411 if (ts->model == 7845) 1412 ads7845_read12_ser(&spi->dev, PWRDOWN); 1413 else 1414 (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux)); 1415 1416 err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); 1417 if (err) 1418 goto err_remove_hwmon; 1419 1420 err = input_register_device(input_dev); 1421 if (err) 1422 goto err_remove_attr_group; 1423 1424 device_init_wakeup(&spi->dev, pdata->wakeup); 1425 1426 /* 1427 * If device does not carry platform data we must have allocated it 1428 * when parsing DT data. 1429 */ 1430 if (!dev_get_platdata(&spi->dev)) 1431 devm_kfree(&spi->dev, (void *)pdata); 1432 1433 return 0; 1434 1435 err_remove_attr_group: 1436 sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); 1437 err_remove_hwmon: 1438 ads784x_hwmon_unregister(spi, ts); 1439 err_free_irq: 1440 free_irq(spi->irq, ts); 1441 err_disable_regulator: 1442 regulator_disable(ts->reg); 1443 err_put_regulator: 1444 regulator_put(ts->reg); 1445 err_free_gpio: 1446 if (!ts->get_pendown_state) 1447 gpio_free(ts->gpio_pendown); 1448 err_cleanup_filter: 1449 if (ts->filter_cleanup) 1450 ts->filter_cleanup(ts->filter_data); 1451 err_free_mem: 1452 input_free_device(input_dev); 1453 kfree(packet); 1454 kfree(ts); 1455 return err; 1456} 1457 1458static int ads7846_remove(struct spi_device *spi) 1459{ 1460 struct ads7846 *ts = spi_get_drvdata(spi); 1461 1462 device_init_wakeup(&spi->dev, false); 1463 1464 sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); 1465 1466 ads7846_disable(ts); 1467 free_irq(ts->spi->irq, ts); 1468 1469 input_unregister_device(ts->input); 1470 1471 ads784x_hwmon_unregister(spi, ts); 1472 1473 regulator_disable(ts->reg); 1474 regulator_put(ts->reg); 1475 1476 if (!ts->get_pendown_state) { 1477 /* 1478 * If we are not using specialized pendown method we must 1479 * have been relying on gpio we set up ourselves. 1480 */ 1481 gpio_free(ts->gpio_pendown); 1482 } 1483 1484 if (ts->filter_cleanup) 1485 ts->filter_cleanup(ts->filter_data); 1486 1487 kfree(ts->packet); 1488 kfree(ts); 1489 1490 dev_dbg(&spi->dev, "unregistered touchscreen\n"); 1491 1492 return 0; 1493} 1494 1495static struct spi_driver ads7846_driver = { 1496 .driver = { 1497 .name = "ads7846", 1498 .owner = THIS_MODULE, 1499 .pm = &ads7846_pm, 1500 .of_match_table = of_match_ptr(ads7846_dt_ids), 1501 }, 1502 .probe = ads7846_probe, 1503 .remove = ads7846_remove, 1504}; 1505 1506module_spi_driver(ads7846_driver); 1507 1508MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); 1509MODULE_LICENSE("GPL"); 1510MODULE_ALIAS("spi:ads7846"); 1511