1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * ADS7846 based touchscreen and sensor driver 4 * 5 * Copyright (c) 2005 David Brownell 6 * Copyright (c) 2006 Nokia Corporation 7 * Various changes: Imre Deak <imre.deak@nokia.com> 8 * 9 * Using code from: 10 * - corgi_ts.c 11 * Copyright (C) 2004-2005 Richard Purdie 12 * - omap_ts.[hc], ads7846.h, ts_osk.c 13 * Copyright (C) 2002 MontaVista Software 14 * Copyright (C) 2004 Texas Instruments 15 * Copyright (C) 2005 Dirk Behme 16 */ 17#include <linux/types.h> 18#include <linux/hwmon.h> 19#include <linux/err.h> 20#include <linux/sched.h> 21#include <linux/delay.h> 22#include <linux/input.h> 23#include <linux/input/touchscreen.h> 24#include <linux/interrupt.h> 25#include <linux/slab.h> 26#include <linux/pm.h> 27#include <linux/of.h> 28#include <linux/of_gpio.h> 29#include <linux/of_device.h> 30#include <linux/gpio.h> 31#include <linux/spi/spi.h> 32#include <linux/spi/ads7846.h> 33#include <linux/regulator/consumer.h> 34#include <linux/module.h> 35#include <asm/irq.h> 36#include <asm/unaligned.h> 37 38/* 39 * This code has been heavily tested on a Nokia 770, and lightly 40 * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). 41 * TSC2046 is just newer ads7846 silicon. 42 * Support for ads7843 tested on Atmel at91sam926x-EK. 43 * Support for ads7845 has only been stubbed in. 44 * Support for Analog Devices AD7873 and AD7843 tested. 45 * 46 * IRQ handling needs a workaround because of a shortcoming in handling 47 * edge triggered IRQs on some platforms like the OMAP1/2. These 48 * platforms don't handle the ARM lazy IRQ disabling properly, thus we 49 * have to maintain our own SW IRQ disabled status. This should be 50 * removed as soon as the affected platform's IRQ handling is fixed. 51 * 52 * App note sbaa036 talks in more detail about accurate sampling... 53 * that ought to help in situations like LCDs inducing noise (which 54 * can also be helped by using synch signals) and more generally. 55 * This driver tries to utilize the measures described in the app 56 * note. The strength of filtering can be set in the board-* specific 57 * files. 58 */ 59 60#define TS_POLL_DELAY 1 /* ms delay before the first sample */ 61#define TS_POLL_PERIOD 5 /* ms delay between samples */ 62 63/* this driver doesn't aim at the peak continuous sample rate */ 64#define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) 65 66struct ads7846_buf { 67 u8 cmd; 68 __be16 data; 69} __packed; 70 71struct ads7846_buf_layout { 72 unsigned int offset; 73 unsigned int count; 74 unsigned int skip; 75}; 76 77/* 78 * We allocate this separately to avoid cache line sharing issues when 79 * driver is used with DMA-based SPI controllers (like atmel_spi) on 80 * systems where main memory is not DMA-coherent (most non-x86 boards). 81 */ 82struct ads7846_packet { 83 unsigned int count; 84 unsigned int count_skip; 85 unsigned int cmds; 86 unsigned int last_cmd_idx; 87 struct ads7846_buf_layout l[5]; 88 struct ads7846_buf *rx; 89 struct ads7846_buf *tx; 90 91 struct ads7846_buf pwrdown_cmd; 92 93 bool ignore; 94 u16 x, y, z1, z2; 95}; 96 97struct ads7846 { 98 struct input_dev *input; 99 char phys[32]; 100 char name[32]; 101 102 struct spi_device *spi; 103 struct regulator *reg; 104 105#if IS_ENABLED(CONFIG_HWMON) 106 struct device *hwmon; 107#endif 108 109 u16 model; 110 u16 vref_mv; 111 u16 vref_delay_usecs; 112 u16 x_plate_ohms; 113 u16 pressure_max; 114 115 bool swap_xy; 116 bool use_internal; 117 118 struct ads7846_packet *packet; 119 120 struct spi_transfer xfer[18]; 121 struct spi_message msg[5]; 122 int msg_count; 123 wait_queue_head_t wait; 124 125 bool pendown; 126 127 int read_cnt; 128 int read_rep; 129 int last_read; 130 131 u16 debounce_max; 132 u16 debounce_tol; 133 u16 debounce_rep; 134 135 u16 penirq_recheck_delay_usecs; 136 137 struct touchscreen_properties core_prop; 138 139 struct mutex lock; 140 bool stopped; /* P: lock */ 141 bool disabled; /* P: lock */ 142 bool suspended; /* P: lock */ 143 144 int (*filter)(void *data, int data_idx, int *val); 145 void *filter_data; 146 void (*filter_cleanup)(void *data); 147 int (*get_pendown_state)(void); 148 int gpio_pendown; 149 150 void (*wait_for_sync)(void); 151}; 152 153/* leave chip selected when we're done, for quicker re-select? */ 154#if 0 155#define CS_CHANGE(xfer) ((xfer).cs_change = 1) 156#else 157#define CS_CHANGE(xfer) ((xfer).cs_change = 0) 158#endif 159 160/*--------------------------------------------------------------------------*/ 161 162/* The ADS7846 has touchscreen and other sensors. 163 * Earlier ads784x chips are somewhat compatible. 164 */ 165#define ADS_START (1 << 7) 166#define ADS_A2A1A0_d_y (1 << 4) /* differential */ 167#define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ 168#define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ 169#define ADS_A2A1A0_d_x (5 << 4) /* differential */ 170#define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ 171#define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ 172#define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ 173#define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ 174#define ADS_8_BIT (1 << 3) 175#define ADS_12_BIT (0 << 3) 176#define ADS_SER (1 << 2) /* non-differential */ 177#define ADS_DFR (0 << 2) /* differential */ 178#define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */ 179#define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ 180#define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ 181#define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ 182 183#define MAX_12BIT ((1<<12)-1) 184 185/* leave ADC powered up (disables penirq) between differential samples */ 186#define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ 187 | ADS_12_BIT | ADS_DFR | \ 188 (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) 189 190#define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) 191#define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) 192#define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) 193#define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) 194#define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ 195 196/* single-ended samples need to first power up reference voltage; 197 * we leave both ADC and VREF powered 198 */ 199#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ 200 | ADS_12_BIT | ADS_SER) 201 202#define REF_ON (READ_12BIT_DFR(x, 1, 1)) 203#define REF_OFF (READ_12BIT_DFR(y, 0, 0)) 204 205/* Order commands in the most optimal way to reduce Vref switching and 206 * settling time: 207 * Measure: X; Vref: X+, X-; IN: Y+ 208 * Measure: Y; Vref: Y+, Y-; IN: X+ 209 * Measure: Z1; Vref: Y+, X-; IN: X+ 210 * Measure: Z2; Vref: Y+, X-; IN: Y- 211 */ 212enum ads7846_cmds { 213 ADS7846_X, 214 ADS7846_Y, 215 ADS7846_Z1, 216 ADS7846_Z2, 217 ADS7846_PWDOWN, 218}; 219 220static int get_pendown_state(struct ads7846 *ts) 221{ 222 if (ts->get_pendown_state) 223 return ts->get_pendown_state(); 224 225 return !gpio_get_value(ts->gpio_pendown); 226} 227 228static void ads7846_report_pen_up(struct ads7846 *ts) 229{ 230 struct input_dev *input = ts->input; 231 232 input_report_key(input, BTN_TOUCH, 0); 233 input_report_abs(input, ABS_PRESSURE, 0); 234 input_sync(input); 235 236 ts->pendown = false; 237 dev_vdbg(&ts->spi->dev, "UP\n"); 238} 239 240/* Must be called with ts->lock held */ 241static void ads7846_stop(struct ads7846 *ts) 242{ 243 if (!ts->disabled && !ts->suspended) { 244 /* Signal IRQ thread to stop polling and disable the handler. */ 245 ts->stopped = true; 246 mb(); 247 wake_up(&ts->wait); 248 disable_irq(ts->spi->irq); 249 } 250} 251 252/* Must be called with ts->lock held */ 253static void ads7846_restart(struct ads7846 *ts) 254{ 255 if (!ts->disabled && !ts->suspended) { 256 /* Check if pen was released since last stop */ 257 if (ts->pendown && !get_pendown_state(ts)) 258 ads7846_report_pen_up(ts); 259 260 /* Tell IRQ thread that it may poll the device. */ 261 ts->stopped = false; 262 mb(); 263 enable_irq(ts->spi->irq); 264 } 265} 266 267/* Must be called with ts->lock held */ 268static void __ads7846_disable(struct ads7846 *ts) 269{ 270 ads7846_stop(ts); 271 regulator_disable(ts->reg); 272 273 /* 274 * We know the chip's in low power mode since we always 275 * leave it that way after every request 276 */ 277} 278 279/* Must be called with ts->lock held */ 280static void __ads7846_enable(struct ads7846 *ts) 281{ 282 int error; 283 284 error = regulator_enable(ts->reg); 285 if (error != 0) 286 dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error); 287 288 ads7846_restart(ts); 289} 290 291static void ads7846_disable(struct ads7846 *ts) 292{ 293 mutex_lock(&ts->lock); 294 295 if (!ts->disabled) { 296 297 if (!ts->suspended) 298 __ads7846_disable(ts); 299 300 ts->disabled = true; 301 } 302 303 mutex_unlock(&ts->lock); 304} 305 306static void ads7846_enable(struct ads7846 *ts) 307{ 308 mutex_lock(&ts->lock); 309 310 if (ts->disabled) { 311 312 ts->disabled = false; 313 314 if (!ts->suspended) 315 __ads7846_enable(ts); 316 } 317 318 mutex_unlock(&ts->lock); 319} 320 321/*--------------------------------------------------------------------------*/ 322 323/* 324 * Non-touchscreen sensors only use single-ended conversions. 325 * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; 326 * ads7846 lets that pin be unconnected, to use internal vREF. 327 */ 328 329struct ser_req { 330 u8 ref_on; 331 u8 command; 332 u8 ref_off; 333 u16 scratch; 334 struct spi_message msg; 335 struct spi_transfer xfer[6]; 336 /* 337 * DMA (thus cache coherency maintenance) requires the 338 * transfer buffers to live in their own cache lines. 339 */ 340 __be16 sample ____cacheline_aligned; 341}; 342 343struct ads7845_ser_req { 344 u8 command[3]; 345 struct spi_message msg; 346 struct spi_transfer xfer[2]; 347 /* 348 * DMA (thus cache coherency maintenance) requires the 349 * transfer buffers to live in their own cache lines. 350 */ 351 u8 sample[3] ____cacheline_aligned; 352}; 353 354static int ads7846_read12_ser(struct device *dev, unsigned command) 355{ 356 struct spi_device *spi = to_spi_device(dev); 357 struct ads7846 *ts = dev_get_drvdata(dev); 358 struct ser_req *req; 359 int status; 360 361 req = kzalloc(sizeof *req, GFP_KERNEL); 362 if (!req) 363 return -ENOMEM; 364 365 spi_message_init(&req->msg); 366 367 /* maybe turn on internal vREF, and let it settle */ 368 if (ts->use_internal) { 369 req->ref_on = REF_ON; 370 req->xfer[0].tx_buf = &req->ref_on; 371 req->xfer[0].len = 1; 372 spi_message_add_tail(&req->xfer[0], &req->msg); 373 374 req->xfer[1].rx_buf = &req->scratch; 375 req->xfer[1].len = 2; 376 377 /* for 1uF, settle for 800 usec; no cap, 100 usec. */ 378 req->xfer[1].delay.value = ts->vref_delay_usecs; 379 req->xfer[1].delay.unit = SPI_DELAY_UNIT_USECS; 380 spi_message_add_tail(&req->xfer[1], &req->msg); 381 382 /* Enable reference voltage */ 383 command |= ADS_PD10_REF_ON; 384 } 385 386 /* Enable ADC in every case */ 387 command |= ADS_PD10_ADC_ON; 388 389 /* take sample */ 390 req->command = (u8) command; 391 req->xfer[2].tx_buf = &req->command; 392 req->xfer[2].len = 1; 393 spi_message_add_tail(&req->xfer[2], &req->msg); 394 395 req->xfer[3].rx_buf = &req->sample; 396 req->xfer[3].len = 2; 397 spi_message_add_tail(&req->xfer[3], &req->msg); 398 399 /* REVISIT: take a few more samples, and compare ... */ 400 401 /* converter in low power mode & enable PENIRQ */ 402 req->ref_off = PWRDOWN; 403 req->xfer[4].tx_buf = &req->ref_off; 404 req->xfer[4].len = 1; 405 spi_message_add_tail(&req->xfer[4], &req->msg); 406 407 req->xfer[5].rx_buf = &req->scratch; 408 req->xfer[5].len = 2; 409 CS_CHANGE(req->xfer[5]); 410 spi_message_add_tail(&req->xfer[5], &req->msg); 411 412 mutex_lock(&ts->lock); 413 ads7846_stop(ts); 414 status = spi_sync(spi, &req->msg); 415 ads7846_restart(ts); 416 mutex_unlock(&ts->lock); 417 418 if (status == 0) { 419 /* on-wire is a must-ignore bit, a BE12 value, then padding */ 420 status = be16_to_cpu(req->sample); 421 status = status >> 3; 422 status &= 0x0fff; 423 } 424 425 kfree(req); 426 return status; 427} 428 429static int ads7845_read12_ser(struct device *dev, unsigned command) 430{ 431 struct spi_device *spi = to_spi_device(dev); 432 struct ads7846 *ts = dev_get_drvdata(dev); 433 struct ads7845_ser_req *req; 434 int status; 435 436 req = kzalloc(sizeof *req, GFP_KERNEL); 437 if (!req) 438 return -ENOMEM; 439 440 spi_message_init(&req->msg); 441 442 req->command[0] = (u8) command; 443 req->xfer[0].tx_buf = req->command; 444 req->xfer[0].rx_buf = req->sample; 445 req->xfer[0].len = 3; 446 spi_message_add_tail(&req->xfer[0], &req->msg); 447 448 mutex_lock(&ts->lock); 449 ads7846_stop(ts); 450 status = spi_sync(spi, &req->msg); 451 ads7846_restart(ts); 452 mutex_unlock(&ts->lock); 453 454 if (status == 0) { 455 /* BE12 value, then padding */ 456 status = get_unaligned_be16(&req->sample[1]); 457 status = status >> 3; 458 status &= 0x0fff; 459 } 460 461 kfree(req); 462 return status; 463} 464 465#if IS_ENABLED(CONFIG_HWMON) 466 467#define SHOW(name, var, adjust) static ssize_t \ 468name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ 469{ \ 470 struct ads7846 *ts = dev_get_drvdata(dev); \ 471 ssize_t v = ads7846_read12_ser(&ts->spi->dev, \ 472 READ_12BIT_SER(var)); \ 473 if (v < 0) \ 474 return v; \ 475 return sprintf(buf, "%u\n", adjust(ts, v)); \ 476} \ 477static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); 478 479 480/* Sysfs conventions report temperatures in millidegrees Celsius. 481 * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high 482 * accuracy scheme without calibration data. For now we won't try either; 483 * userspace sees raw sensor values, and must scale/calibrate appropriately. 484 */ 485static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) 486{ 487 return v; 488} 489 490SHOW(temp0, temp0, null_adjust) /* temp1_input */ 491SHOW(temp1, temp1, null_adjust) /* temp2_input */ 492 493 494/* sysfs conventions report voltages in millivolts. We can convert voltages 495 * if we know vREF. userspace may need to scale vAUX to match the board's 496 * external resistors; we assume that vBATT only uses the internal ones. 497 */ 498static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) 499{ 500 unsigned retval = v; 501 502 /* external resistors may scale vAUX into 0..vREF */ 503 retval *= ts->vref_mv; 504 retval = retval >> 12; 505 506 return retval; 507} 508 509static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) 510{ 511 unsigned retval = vaux_adjust(ts, v); 512 513 /* ads7846 has a resistor ladder to scale this signal down */ 514 if (ts->model == 7846) 515 retval *= 4; 516 517 return retval; 518} 519 520SHOW(in0_input, vaux, vaux_adjust) 521SHOW(in1_input, vbatt, vbatt_adjust) 522 523static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr, 524 int index) 525{ 526 struct device *dev = container_of(kobj, struct device, kobj); 527 struct ads7846 *ts = dev_get_drvdata(dev); 528 529 if (ts->model == 7843 && index < 2) /* in0, in1 */ 530 return 0; 531 if (ts->model == 7845 && index != 2) /* in0 */ 532 return 0; 533 534 return attr->mode; 535} 536 537static struct attribute *ads7846_attributes[] = { 538 &dev_attr_temp0.attr, /* 0 */ 539 &dev_attr_temp1.attr, /* 1 */ 540 &dev_attr_in0_input.attr, /* 2 */ 541 &dev_attr_in1_input.attr, /* 3 */ 542 NULL, 543}; 544 545static const struct attribute_group ads7846_attr_group = { 546 .attrs = ads7846_attributes, 547 .is_visible = ads7846_is_visible, 548}; 549__ATTRIBUTE_GROUPS(ads7846_attr); 550 551static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) 552{ 553 /* hwmon sensors need a reference voltage */ 554 switch (ts->model) { 555 case 7846: 556 if (!ts->vref_mv) { 557 dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); 558 ts->vref_mv = 2500; 559 ts->use_internal = true; 560 } 561 break; 562 case 7845: 563 case 7843: 564 if (!ts->vref_mv) { 565 dev_warn(&spi->dev, 566 "external vREF for ADS%d not specified\n", 567 ts->model); 568 return 0; 569 } 570 break; 571 } 572 573 ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias, 574 ts, ads7846_attr_groups); 575 576 return PTR_ERR_OR_ZERO(ts->hwmon); 577} 578 579static void ads784x_hwmon_unregister(struct spi_device *spi, 580 struct ads7846 *ts) 581{ 582 if (ts->hwmon) 583 hwmon_device_unregister(ts->hwmon); 584} 585 586#else 587static inline int ads784x_hwmon_register(struct spi_device *spi, 588 struct ads7846 *ts) 589{ 590 return 0; 591} 592 593static inline void ads784x_hwmon_unregister(struct spi_device *spi, 594 struct ads7846 *ts) 595{ 596} 597#endif 598 599static ssize_t ads7846_pen_down_show(struct device *dev, 600 struct device_attribute *attr, char *buf) 601{ 602 struct ads7846 *ts = dev_get_drvdata(dev); 603 604 return sprintf(buf, "%u\n", ts->pendown); 605} 606 607static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); 608 609static ssize_t ads7846_disable_show(struct device *dev, 610 struct device_attribute *attr, char *buf) 611{ 612 struct ads7846 *ts = dev_get_drvdata(dev); 613 614 return sprintf(buf, "%u\n", ts->disabled); 615} 616 617static ssize_t ads7846_disable_store(struct device *dev, 618 struct device_attribute *attr, 619 const char *buf, size_t count) 620{ 621 struct ads7846 *ts = dev_get_drvdata(dev); 622 unsigned int i; 623 int err; 624 625 err = kstrtouint(buf, 10, &i); 626 if (err) 627 return err; 628 629 if (i) 630 ads7846_disable(ts); 631 else 632 ads7846_enable(ts); 633 634 return count; 635} 636 637static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); 638 639static struct attribute *ads784x_attributes[] = { 640 &dev_attr_pen_down.attr, 641 &dev_attr_disable.attr, 642 NULL, 643}; 644 645static const struct attribute_group ads784x_attr_group = { 646 .attrs = ads784x_attributes, 647}; 648 649/*--------------------------------------------------------------------------*/ 650 651static void null_wait_for_sync(void) 652{ 653} 654 655static int ads7846_debounce_filter(void *ads, int data_idx, int *val) 656{ 657 struct ads7846 *ts = ads; 658 659 if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { 660 /* Start over collecting consistent readings. */ 661 ts->read_rep = 0; 662 /* 663 * Repeat it, if this was the first read or the read 664 * wasn't consistent enough. 665 */ 666 if (ts->read_cnt < ts->debounce_max) { 667 ts->last_read = *val; 668 ts->read_cnt++; 669 return ADS7846_FILTER_REPEAT; 670 } else { 671 /* 672 * Maximum number of debouncing reached and still 673 * not enough number of consistent readings. Abort 674 * the whole sample, repeat it in the next sampling 675 * period. 676 */ 677 ts->read_cnt = 0; 678 return ADS7846_FILTER_IGNORE; 679 } 680 } else { 681 if (++ts->read_rep > ts->debounce_rep) { 682 /* 683 * Got a good reading for this coordinate, 684 * go for the next one. 685 */ 686 ts->read_cnt = 0; 687 ts->read_rep = 0; 688 return ADS7846_FILTER_OK; 689 } else { 690 /* Read more values that are consistent. */ 691 ts->read_cnt++; 692 return ADS7846_FILTER_REPEAT; 693 } 694 } 695} 696 697static int ads7846_no_filter(void *ads, int data_idx, int *val) 698{ 699 return ADS7846_FILTER_OK; 700} 701 702static int ads7846_get_value(struct ads7846_buf *buf) 703{ 704 int value; 705 706 value = be16_to_cpup(&buf->data); 707 708 /* enforce ADC output is 12 bits width */ 709 return (value >> 3) & 0xfff; 710} 711 712static void ads7846_set_cmd_val(struct ads7846 *ts, enum ads7846_cmds cmd_idx, 713 u16 val) 714{ 715 struct ads7846_packet *packet = ts->packet; 716 717 switch (cmd_idx) { 718 case ADS7846_Y: 719 packet->y = val; 720 break; 721 case ADS7846_X: 722 packet->x = val; 723 break; 724 case ADS7846_Z1: 725 packet->z1 = val; 726 break; 727 case ADS7846_Z2: 728 packet->z2 = val; 729 break; 730 default: 731 WARN_ON_ONCE(1); 732 } 733} 734 735static u8 ads7846_get_cmd(enum ads7846_cmds cmd_idx, int vref) 736{ 737 switch (cmd_idx) { 738 case ADS7846_Y: 739 return READ_Y(vref); 740 case ADS7846_X: 741 return READ_X(vref); 742 743 /* 7846 specific commands */ 744 case ADS7846_Z1: 745 return READ_Z1(vref); 746 case ADS7846_Z2: 747 return READ_Z2(vref); 748 case ADS7846_PWDOWN: 749 return PWRDOWN; 750 default: 751 WARN_ON_ONCE(1); 752 } 753 754 return 0; 755} 756 757static bool ads7846_cmd_need_settle(enum ads7846_cmds cmd_idx) 758{ 759 switch (cmd_idx) { 760 case ADS7846_X: 761 case ADS7846_Y: 762 case ADS7846_Z1: 763 case ADS7846_Z2: 764 return true; 765 case ADS7846_PWDOWN: 766 return false; 767 default: 768 WARN_ON_ONCE(1); 769 } 770 771 return false; 772} 773 774static int ads7846_filter(struct ads7846 *ts) 775{ 776 struct ads7846_packet *packet = ts->packet; 777 int action; 778 int val; 779 unsigned int cmd_idx, b; 780 781 packet->ignore = false; 782 for (cmd_idx = packet->last_cmd_idx; cmd_idx < packet->cmds - 1; cmd_idx++) { 783 struct ads7846_buf_layout *l = &packet->l[cmd_idx]; 784 785 packet->last_cmd_idx = cmd_idx; 786 787 for (b = l->skip; b < l->count; b++) { 788 val = ads7846_get_value(&packet->rx[l->offset + b]); 789 790 action = ts->filter(ts->filter_data, cmd_idx, &val); 791 if (action == ADS7846_FILTER_REPEAT) { 792 if (b == l->count - 1) 793 return -EAGAIN; 794 } else if (action == ADS7846_FILTER_OK) { 795 ads7846_set_cmd_val(ts, cmd_idx, val); 796 break; 797 } else { 798 packet->ignore = true; 799 return 0; 800 } 801 } 802 } 803 804 return 0; 805} 806 807static void ads7846_read_state(struct ads7846 *ts) 808{ 809 struct ads7846_packet *packet = ts->packet; 810 struct spi_message *m; 811 int msg_idx = 0; 812 int error; 813 814 packet->last_cmd_idx = 0; 815 816 while (true) { 817 ts->wait_for_sync(); 818 819 m = &ts->msg[msg_idx]; 820 error = spi_sync(ts->spi, m); 821 if (error) { 822 dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); 823 packet->ignore = true; 824 return; 825 } 826 827 error = ads7846_filter(ts); 828 if (error) 829 continue; 830 831 return; 832 } 833} 834 835static void ads7846_report_state(struct ads7846 *ts) 836{ 837 struct ads7846_packet *packet = ts->packet; 838 unsigned int Rt; 839 u16 x, y, z1, z2; 840 841 x = packet->x; 842 y = packet->y; 843 if (ts->model == 7845) { 844 z1 = 0; 845 z2 = 0; 846 } else { 847 z1 = packet->z1; 848 z2 = packet->z2; 849 } 850 851 /* range filtering */ 852 if (x == MAX_12BIT) 853 x = 0; 854 855 if (ts->model == 7843 || ts->model == 7845) { 856 Rt = ts->pressure_max / 2; 857 } else if (likely(x && z1)) { 858 /* compute touch pressure resistance using equation #2 */ 859 Rt = z2; 860 Rt -= z1; 861 Rt *= ts->x_plate_ohms; 862 Rt = DIV_ROUND_CLOSEST(Rt, 16); 863 Rt *= x; 864 Rt /= z1; 865 Rt = DIV_ROUND_CLOSEST(Rt, 256); 866 } else { 867 Rt = 0; 868 } 869 870 /* 871 * Sample found inconsistent by debouncing or pressure is beyond 872 * the maximum. Don't report it to user space, repeat at least 873 * once more the measurement 874 */ 875 if (packet->ignore || Rt > ts->pressure_max) { 876 dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", 877 packet->ignore, Rt); 878 return; 879 } 880 881 /* 882 * Maybe check the pendown state before reporting. This discards 883 * false readings when the pen is lifted. 884 */ 885 if (ts->penirq_recheck_delay_usecs) { 886 udelay(ts->penirq_recheck_delay_usecs); 887 if (!get_pendown_state(ts)) 888 Rt = 0; 889 } 890 891 /* 892 * NOTE: We can't rely on the pressure to determine the pen down 893 * state, even this controller has a pressure sensor. The pressure 894 * value can fluctuate for quite a while after lifting the pen and 895 * in some cases may not even settle at the expected value. 896 * 897 * The only safe way to check for the pen up condition is in the 898 * timer by reading the pen signal state (it's a GPIO _and_ IRQ). 899 */ 900 if (Rt) { 901 struct input_dev *input = ts->input; 902 903 if (!ts->pendown) { 904 input_report_key(input, BTN_TOUCH, 1); 905 ts->pendown = true; 906 dev_vdbg(&ts->spi->dev, "DOWN\n"); 907 } 908 909 touchscreen_report_pos(input, &ts->core_prop, x, y, false); 910 input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); 911 912 input_sync(input); 913 dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); 914 } 915} 916 917static irqreturn_t ads7846_hard_irq(int irq, void *handle) 918{ 919 struct ads7846 *ts = handle; 920 921 return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; 922} 923 924 925static irqreturn_t ads7846_irq(int irq, void *handle) 926{ 927 struct ads7846 *ts = handle; 928 929 /* Start with a small delay before checking pendown state */ 930 msleep(TS_POLL_DELAY); 931 932 while (!ts->stopped && get_pendown_state(ts)) { 933 934 /* pen is down, continue with the measurement */ 935 ads7846_read_state(ts); 936 937 if (!ts->stopped) 938 ads7846_report_state(ts); 939 940 wait_event_timeout(ts->wait, ts->stopped, 941 msecs_to_jiffies(TS_POLL_PERIOD)); 942 } 943 944 if (ts->pendown && !ts->stopped) 945 ads7846_report_pen_up(ts); 946 947 return IRQ_HANDLED; 948} 949 950static int __maybe_unused ads7846_suspend(struct device *dev) 951{ 952 struct ads7846 *ts = dev_get_drvdata(dev); 953 954 mutex_lock(&ts->lock); 955 956 if (!ts->suspended) { 957 958 if (!ts->disabled) 959 __ads7846_disable(ts); 960 961 if (device_may_wakeup(&ts->spi->dev)) 962 enable_irq_wake(ts->spi->irq); 963 964 ts->suspended = true; 965 } 966 967 mutex_unlock(&ts->lock); 968 969 return 0; 970} 971 972static int __maybe_unused ads7846_resume(struct device *dev) 973{ 974 struct ads7846 *ts = dev_get_drvdata(dev); 975 976 mutex_lock(&ts->lock); 977 978 if (ts->suspended) { 979 980 ts->suspended = false; 981 982 if (device_may_wakeup(&ts->spi->dev)) 983 disable_irq_wake(ts->spi->irq); 984 985 if (!ts->disabled) 986 __ads7846_enable(ts); 987 } 988 989 mutex_unlock(&ts->lock); 990 991 return 0; 992} 993 994static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume); 995 996static int ads7846_setup_pendown(struct spi_device *spi, 997 struct ads7846 *ts, 998 const struct ads7846_platform_data *pdata) 999{ 1000 int err; 1001 1002 /* 1003 * REVISIT when the irq can be triggered active-low, or if for some 1004 * reason the touchscreen isn't hooked up, we don't need to access 1005 * the pendown state. 1006 */ 1007 1008 if (pdata->get_pendown_state) { 1009 ts->get_pendown_state = pdata->get_pendown_state; 1010 } else if (gpio_is_valid(pdata->gpio_pendown)) { 1011 1012 err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN, 1013 "ads7846_pendown"); 1014 if (err) { 1015 dev_err(&spi->dev, 1016 "failed to request/setup pendown GPIO%d: %d\n", 1017 pdata->gpio_pendown, err); 1018 return err; 1019 } 1020 1021 ts->gpio_pendown = pdata->gpio_pendown; 1022 1023 if (pdata->gpio_pendown_debounce) 1024 gpio_set_debounce(pdata->gpio_pendown, 1025 pdata->gpio_pendown_debounce); 1026 } else { 1027 dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); 1028 return -EINVAL; 1029 } 1030 1031 return 0; 1032} 1033 1034/* 1035 * Set up the transfers to read touchscreen state; this assumes we 1036 * use formula #2 for pressure, not #3. 1037 */ 1038static int ads7846_setup_spi_msg(struct ads7846 *ts, 1039 const struct ads7846_platform_data *pdata) 1040{ 1041 struct spi_message *m = &ts->msg[0]; 1042 struct spi_transfer *x = ts->xfer; 1043 struct ads7846_packet *packet = ts->packet; 1044 int vref = pdata->keep_vref_on; 1045 unsigned int count, offset = 0; 1046 unsigned int cmd_idx, b; 1047 unsigned long time; 1048 size_t size = 0; 1049 1050 /* time per bit */ 1051 time = NSEC_PER_SEC / ts->spi->max_speed_hz; 1052 1053 count = pdata->settle_delay_usecs * NSEC_PER_USEC / time; 1054 packet->count_skip = DIV_ROUND_UP(count, 24); 1055 1056 if (ts->debounce_max && ts->debounce_rep) 1057 /* ads7846_debounce_filter() is making ts->debounce_rep + 2 1058 * reads. So we need to get all samples for normal case. */ 1059 packet->count = ts->debounce_rep + 2; 1060 else 1061 packet->count = 1; 1062 1063 if (ts->model == 7846) 1064 packet->cmds = 5; /* x, y, z1, z2, pwdown */ 1065 else 1066 packet->cmds = 3; /* x, y, pwdown */ 1067 1068 for (cmd_idx = 0; cmd_idx < packet->cmds; cmd_idx++) { 1069 struct ads7846_buf_layout *l = &packet->l[cmd_idx]; 1070 unsigned int max_count; 1071 1072 if (cmd_idx == packet->cmds - 1) 1073 cmd_idx = ADS7846_PWDOWN; 1074 1075 if (ads7846_cmd_need_settle(cmd_idx)) 1076 max_count = packet->count + packet->count_skip; 1077 else 1078 max_count = packet->count; 1079 1080 l->offset = offset; 1081 offset += max_count; 1082 l->count = max_count; 1083 l->skip = packet->count_skip; 1084 size += sizeof(*packet->tx) * max_count; 1085 } 1086 1087 packet->tx = devm_kzalloc(&ts->spi->dev, size, GFP_KERNEL); 1088 if (!packet->tx) 1089 return -ENOMEM; 1090 1091 packet->rx = devm_kzalloc(&ts->spi->dev, size, GFP_KERNEL); 1092 if (!packet->rx) 1093 return -ENOMEM; 1094 1095 if (ts->model == 7873) { 1096 /* 1097 * The AD7873 is almost identical to the ADS7846 1098 * keep VREF off during differential/ratiometric 1099 * conversion modes. 1100 */ 1101 ts->model = 7846; 1102 vref = 0; 1103 } 1104 1105 ts->msg_count = 1; 1106 spi_message_init(m); 1107 m->context = ts; 1108 1109 for (cmd_idx = 0; cmd_idx < packet->cmds; cmd_idx++) { 1110 struct ads7846_buf_layout *l = &packet->l[cmd_idx]; 1111 u8 cmd; 1112 1113 if (cmd_idx == packet->cmds - 1) 1114 cmd_idx = ADS7846_PWDOWN; 1115 1116 cmd = ads7846_get_cmd(cmd_idx, vref); 1117 1118 for (b = 0; b < l->count; b++) 1119 packet->tx[l->offset + b].cmd = cmd; 1120 } 1121 1122 x->tx_buf = packet->tx; 1123 x->rx_buf = packet->rx; 1124 x->len = size; 1125 spi_message_add_tail(x, m); 1126 1127 return 0; 1128} 1129 1130#ifdef CONFIG_OF 1131static const struct of_device_id ads7846_dt_ids[] = { 1132 { .compatible = "ti,tsc2046", .data = (void *) 7846 }, 1133 { .compatible = "ti,ads7843", .data = (void *) 7843 }, 1134 { .compatible = "ti,ads7845", .data = (void *) 7845 }, 1135 { .compatible = "ti,ads7846", .data = (void *) 7846 }, 1136 { .compatible = "ti,ads7873", .data = (void *) 7873 }, 1137 { } 1138}; 1139MODULE_DEVICE_TABLE(of, ads7846_dt_ids); 1140 1141static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) 1142{ 1143 struct ads7846_platform_data *pdata; 1144 struct device_node *node = dev->of_node; 1145 const struct of_device_id *match; 1146 u32 value; 1147 1148 if (!node) { 1149 dev_err(dev, "Device does not have associated DT data\n"); 1150 return ERR_PTR(-EINVAL); 1151 } 1152 1153 match = of_match_device(ads7846_dt_ids, dev); 1154 if (!match) { 1155 dev_err(dev, "Unknown device model\n"); 1156 return ERR_PTR(-EINVAL); 1157 } 1158 1159 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 1160 if (!pdata) 1161 return ERR_PTR(-ENOMEM); 1162 1163 pdata->model = (unsigned long)match->data; 1164 1165 of_property_read_u16(node, "ti,vref-delay-usecs", 1166 &pdata->vref_delay_usecs); 1167 of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv); 1168 pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on"); 1169 1170 pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy"); 1171 1172 of_property_read_u16(node, "ti,settle-delay-usec", 1173 &pdata->settle_delay_usecs); 1174 of_property_read_u16(node, "ti,penirq-recheck-delay-usecs", 1175 &pdata->penirq_recheck_delay_usecs); 1176 1177 of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms); 1178 of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms); 1179 1180 of_property_read_u16(node, "ti,x-min", &pdata->x_min); 1181 of_property_read_u16(node, "ti,y-min", &pdata->y_min); 1182 of_property_read_u16(node, "ti,x-max", &pdata->x_max); 1183 of_property_read_u16(node, "ti,y-max", &pdata->y_max); 1184 1185 /* 1186 * touchscreen-max-pressure gets parsed during 1187 * touchscreen_parse_properties() 1188 */ 1189 of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min); 1190 if (!of_property_read_u32(node, "touchscreen-min-pressure", &value)) 1191 pdata->pressure_min = (u16) value; 1192 of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max); 1193 1194 of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max); 1195 if (!of_property_read_u32(node, "touchscreen-average-samples", &value)) 1196 pdata->debounce_max = (u16) value; 1197 of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol); 1198 of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep); 1199 1200 of_property_read_u32(node, "ti,pendown-gpio-debounce", 1201 &pdata->gpio_pendown_debounce); 1202 1203 pdata->wakeup = of_property_read_bool(node, "wakeup-source") || 1204 of_property_read_bool(node, "linux,wakeup"); 1205 1206 pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0); 1207 1208 return pdata; 1209} 1210#else 1211static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) 1212{ 1213 dev_err(dev, "no platform data defined\n"); 1214 return ERR_PTR(-EINVAL); 1215} 1216#endif 1217 1218static int ads7846_probe(struct spi_device *spi) 1219{ 1220 const struct ads7846_platform_data *pdata; 1221 struct ads7846 *ts; 1222 struct ads7846_packet *packet; 1223 struct input_dev *input_dev; 1224 unsigned long irq_flags; 1225 int err; 1226 1227 if (!spi->irq) { 1228 dev_dbg(&spi->dev, "no IRQ?\n"); 1229 return -EINVAL; 1230 } 1231 1232 /* don't exceed max specified sample rate */ 1233 if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { 1234 dev_err(&spi->dev, "f(sample) %d KHz?\n", 1235 (spi->max_speed_hz/SAMPLE_BITS)/1000); 1236 return -EINVAL; 1237 } 1238 1239 /* 1240 * We'd set TX word size 8 bits and RX word size to 13 bits ... except 1241 * that even if the hardware can do that, the SPI controller driver 1242 * may not. So we stick to very-portable 8 bit words, both RX and TX. 1243 */ 1244 spi->bits_per_word = 8; 1245 spi->mode = SPI_MODE_0; 1246 err = spi_setup(spi); 1247 if (err < 0) 1248 return err; 1249 1250 ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); 1251 packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); 1252 input_dev = input_allocate_device(); 1253 if (!ts || !packet || !input_dev) { 1254 err = -ENOMEM; 1255 goto err_free_mem; 1256 } 1257 1258 spi_set_drvdata(spi, ts); 1259 1260 ts->packet = packet; 1261 ts->spi = spi; 1262 ts->input = input_dev; 1263 1264 mutex_init(&ts->lock); 1265 init_waitqueue_head(&ts->wait); 1266 1267 pdata = dev_get_platdata(&spi->dev); 1268 if (!pdata) { 1269 pdata = ads7846_probe_dt(&spi->dev); 1270 if (IS_ERR(pdata)) { 1271 err = PTR_ERR(pdata); 1272 goto err_free_mem; 1273 } 1274 } 1275 1276 ts->model = pdata->model ? : 7846; 1277 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; 1278 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; 1279 ts->vref_mv = pdata->vref_mv; 1280 1281 if (pdata->filter != NULL) { 1282 if (pdata->filter_init != NULL) { 1283 err = pdata->filter_init(pdata, &ts->filter_data); 1284 if (err < 0) 1285 goto err_free_mem; 1286 } 1287 ts->filter = pdata->filter; 1288 ts->filter_cleanup = pdata->filter_cleanup; 1289 } else if (pdata->debounce_max) { 1290 ts->debounce_max = pdata->debounce_max; 1291 if (ts->debounce_max < 2) 1292 ts->debounce_max = 2; 1293 ts->debounce_tol = pdata->debounce_tol; 1294 ts->debounce_rep = pdata->debounce_rep; 1295 ts->filter = ads7846_debounce_filter; 1296 ts->filter_data = ts; 1297 } else { 1298 ts->filter = ads7846_no_filter; 1299 } 1300 1301 err = ads7846_setup_pendown(spi, ts, pdata); 1302 if (err) 1303 goto err_cleanup_filter; 1304 1305 if (pdata->penirq_recheck_delay_usecs) 1306 ts->penirq_recheck_delay_usecs = 1307 pdata->penirq_recheck_delay_usecs; 1308 1309 ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; 1310 1311 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); 1312 snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); 1313 1314 input_dev->name = ts->name; 1315 input_dev->phys = ts->phys; 1316 input_dev->dev.parent = &spi->dev; 1317 1318 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 1319 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 1320 input_set_abs_params(input_dev, ABS_X, 1321 pdata->x_min ? : 0, 1322 pdata->x_max ? : MAX_12BIT, 1323 0, 0); 1324 input_set_abs_params(input_dev, ABS_Y, 1325 pdata->y_min ? : 0, 1326 pdata->y_max ? : MAX_12BIT, 1327 0, 0); 1328 if (ts->model != 7845) 1329 input_set_abs_params(input_dev, ABS_PRESSURE, 1330 pdata->pressure_min, pdata->pressure_max, 0, 0); 1331 1332 /* 1333 * Parse common framework properties. Must be done here to ensure the 1334 * correct behaviour in case of using the legacy vendor bindings. The 1335 * general binding value overrides the vendor specific one. 1336 */ 1337 touchscreen_parse_properties(ts->input, false, &ts->core_prop); 1338 ts->pressure_max = input_abs_get_max(input_dev, ABS_PRESSURE) ? : ~0; 1339 1340 /* 1341 * Check if legacy ti,swap-xy binding is used instead of 1342 * touchscreen-swapped-x-y 1343 */ 1344 if (!ts->core_prop.swap_x_y && pdata->swap_xy) { 1345 swap(input_dev->absinfo[ABS_X], input_dev->absinfo[ABS_Y]); 1346 ts->core_prop.swap_x_y = true; 1347 } 1348 1349 ads7846_setup_spi_msg(ts, pdata); 1350 1351 ts->reg = regulator_get(&spi->dev, "vcc"); 1352 if (IS_ERR(ts->reg)) { 1353 err = PTR_ERR(ts->reg); 1354 dev_err(&spi->dev, "unable to get regulator: %d\n", err); 1355 goto err_free_gpio; 1356 } 1357 1358 err = regulator_enable(ts->reg); 1359 if (err) { 1360 dev_err(&spi->dev, "unable to enable regulator: %d\n", err); 1361 goto err_put_regulator; 1362 } 1363 1364 irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; 1365 irq_flags |= IRQF_ONESHOT; 1366 1367 err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, 1368 irq_flags, spi->dev.driver->name, ts); 1369 if (err && !pdata->irq_flags) { 1370 dev_info(&spi->dev, 1371 "trying pin change workaround on irq %d\n", spi->irq); 1372 irq_flags |= IRQF_TRIGGER_RISING; 1373 err = request_threaded_irq(spi->irq, 1374 ads7846_hard_irq, ads7846_irq, 1375 irq_flags, spi->dev.driver->name, ts); 1376 } 1377 1378 if (err) { 1379 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); 1380 goto err_disable_regulator; 1381 } 1382 1383 err = ads784x_hwmon_register(spi, ts); 1384 if (err) 1385 goto err_free_irq; 1386 1387 dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); 1388 1389 /* 1390 * Take a first sample, leaving nPENIRQ active and vREF off; avoid 1391 * the touchscreen, in case it's not connected. 1392 */ 1393 if (ts->model == 7845) 1394 ads7845_read12_ser(&spi->dev, PWRDOWN); 1395 else 1396 (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux)); 1397 1398 err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); 1399 if (err) 1400 goto err_remove_hwmon; 1401 1402 err = input_register_device(input_dev); 1403 if (err) 1404 goto err_remove_attr_group; 1405 1406 device_init_wakeup(&spi->dev, pdata->wakeup); 1407 1408 /* 1409 * If device does not carry platform data we must have allocated it 1410 * when parsing DT data. 1411 */ 1412 if (!dev_get_platdata(&spi->dev)) 1413 devm_kfree(&spi->dev, (void *)pdata); 1414 1415 return 0; 1416 1417 err_remove_attr_group: 1418 sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); 1419 err_remove_hwmon: 1420 ads784x_hwmon_unregister(spi, ts); 1421 err_free_irq: 1422 free_irq(spi->irq, ts); 1423 err_disable_regulator: 1424 regulator_disable(ts->reg); 1425 err_put_regulator: 1426 regulator_put(ts->reg); 1427 err_free_gpio: 1428 if (!ts->get_pendown_state) 1429 gpio_free(ts->gpio_pendown); 1430 err_cleanup_filter: 1431 if (ts->filter_cleanup) 1432 ts->filter_cleanup(ts->filter_data); 1433 err_free_mem: 1434 input_free_device(input_dev); 1435 kfree(packet); 1436 kfree(ts); 1437 return err; 1438} 1439 1440static int ads7846_remove(struct spi_device *spi) 1441{ 1442 struct ads7846 *ts = spi_get_drvdata(spi); 1443 1444 sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); 1445 1446 ads7846_disable(ts); 1447 free_irq(ts->spi->irq, ts); 1448 1449 input_unregister_device(ts->input); 1450 1451 ads784x_hwmon_unregister(spi, ts); 1452 1453 regulator_put(ts->reg); 1454 1455 if (!ts->get_pendown_state) { 1456 /* 1457 * If we are not using specialized pendown method we must 1458 * have been relying on gpio we set up ourselves. 1459 */ 1460 gpio_free(ts->gpio_pendown); 1461 } 1462 1463 if (ts->filter_cleanup) 1464 ts->filter_cleanup(ts->filter_data); 1465 1466 kfree(ts->packet); 1467 kfree(ts); 1468 1469 dev_dbg(&spi->dev, "unregistered touchscreen\n"); 1470 1471 return 0; 1472} 1473 1474static struct spi_driver ads7846_driver = { 1475 .driver = { 1476 .name = "ads7846", 1477 .pm = &ads7846_pm, 1478 .of_match_table = of_match_ptr(ads7846_dt_ids), 1479 }, 1480 .probe = ads7846_probe, 1481 .remove = ads7846_remove, 1482}; 1483 1484module_spi_driver(ads7846_driver); 1485 1486MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); 1487MODULE_LICENSE("GPL"); 1488MODULE_ALIAS("spi:ads7846"); 1489