1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc. 4 * 5 * Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver 6 * Based on: ads7846.c 7 * 8 * Bugs: Enter bugs at http://blackfin.uclinux.org/ 9 * 10 * History: 11 * Copyright (c) 2005 David Brownell 12 * Copyright (c) 2006 Nokia Corporation 13 * Various changes: Imre Deak <imre.deak@nokia.com> 14 * 15 * Using code from: 16 * - corgi_ts.c 17 * Copyright (C) 2004-2005 Richard Purdie 18 * - omap_ts.[hc], ads7846.h, ts_osk.c 19 * Copyright (C) 2002 MontaVista Software 20 * Copyright (C) 2004 Texas Instruments 21 * Copyright (C) 2005 Dirk Behme 22 */ 23 24 25#include <linux/device.h> 26#include <linux/delay.h> 27#include <linux/input.h> 28#include <linux/interrupt.h> 29#include <linux/pm.h> 30#include <linux/slab.h> 31#include <linux/spi/spi.h> 32#include <linux/spi/ad7877.h> 33#include <linux/module.h> 34#include <asm/irq.h> 35 36#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100) 37 38#define MAX_SPI_FREQ_HZ 20000000 39#define MAX_12BIT ((1<<12)-1) 40 41#define AD7877_REG_ZEROS 0 42#define AD7877_REG_CTRL1 1 43#define AD7877_REG_CTRL2 2 44#define AD7877_REG_ALERT 3 45#define AD7877_REG_AUX1HIGH 4 46#define AD7877_REG_AUX1LOW 5 47#define AD7877_REG_BAT1HIGH 6 48#define AD7877_REG_BAT1LOW 7 49#define AD7877_REG_BAT2HIGH 8 50#define AD7877_REG_BAT2LOW 9 51#define AD7877_REG_TEMP1HIGH 10 52#define AD7877_REG_TEMP1LOW 11 53#define AD7877_REG_SEQ0 12 54#define AD7877_REG_SEQ1 13 55#define AD7877_REG_DAC 14 56#define AD7877_REG_NONE1 15 57#define AD7877_REG_EXTWRITE 15 58#define AD7877_REG_XPLUS 16 59#define AD7877_REG_YPLUS 17 60#define AD7877_REG_Z2 18 61#define AD7877_REG_aux1 19 62#define AD7877_REG_aux2 20 63#define AD7877_REG_aux3 21 64#define AD7877_REG_bat1 22 65#define AD7877_REG_bat2 23 66#define AD7877_REG_temp1 24 67#define AD7877_REG_temp2 25 68#define AD7877_REG_Z1 26 69#define AD7877_REG_GPIOCTRL1 27 70#define AD7877_REG_GPIOCTRL2 28 71#define AD7877_REG_GPIODATA 29 72#define AD7877_REG_NONE2 30 73#define AD7877_REG_NONE3 31 74 75#define AD7877_SEQ_YPLUS_BIT (1<<11) 76#define AD7877_SEQ_XPLUS_BIT (1<<10) 77#define AD7877_SEQ_Z2_BIT (1<<9) 78#define AD7877_SEQ_AUX1_BIT (1<<8) 79#define AD7877_SEQ_AUX2_BIT (1<<7) 80#define AD7877_SEQ_AUX3_BIT (1<<6) 81#define AD7877_SEQ_BAT1_BIT (1<<5) 82#define AD7877_SEQ_BAT2_BIT (1<<4) 83#define AD7877_SEQ_TEMP1_BIT (1<<3) 84#define AD7877_SEQ_TEMP2_BIT (1<<2) 85#define AD7877_SEQ_Z1_BIT (1<<1) 86 87enum { 88 AD7877_SEQ_YPOS = 0, 89 AD7877_SEQ_XPOS = 1, 90 AD7877_SEQ_Z2 = 2, 91 AD7877_SEQ_AUX1 = 3, 92 AD7877_SEQ_AUX2 = 4, 93 AD7877_SEQ_AUX3 = 5, 94 AD7877_SEQ_BAT1 = 6, 95 AD7877_SEQ_BAT2 = 7, 96 AD7877_SEQ_TEMP1 = 8, 97 AD7877_SEQ_TEMP2 = 9, 98 AD7877_SEQ_Z1 = 10, 99 AD7877_NR_SENSE = 11, 100}; 101 102/* DAC Register Default RANGE 0 to Vcc, Volatge Mode, DAC On */ 103#define AD7877_DAC_CONF 0x1 104 105/* If gpio3 is set AUX3/GPIO3 acts as GPIO Output */ 106#define AD7877_EXTW_GPIO_3_CONF 0x1C4 107#define AD7877_EXTW_GPIO_DATA 0x200 108 109/* Control REG 2 */ 110#define AD7877_TMR(x) ((x & 0x3) << 0) 111#define AD7877_REF(x) ((x & 0x1) << 2) 112#define AD7877_POL(x) ((x & 0x1) << 3) 113#define AD7877_FCD(x) ((x & 0x3) << 4) 114#define AD7877_PM(x) ((x & 0x3) << 6) 115#define AD7877_ACQ(x) ((x & 0x3) << 8) 116#define AD7877_AVG(x) ((x & 0x3) << 10) 117 118/* Control REG 1 */ 119#define AD7877_SER (1 << 11) /* non-differential */ 120#define AD7877_DFR (0 << 11) /* differential */ 121 122#define AD7877_MODE_NOC (0) /* Do not convert */ 123#define AD7877_MODE_SCC (1) /* Single channel conversion */ 124#define AD7877_MODE_SEQ0 (2) /* Sequence 0 in Slave Mode */ 125#define AD7877_MODE_SEQ1 (3) /* Sequence 1 in Master Mode */ 126 127#define AD7877_CHANADD(x) ((x&0xF)<<7) 128#define AD7877_READADD(x) ((x)<<2) 129#define AD7877_WRITEADD(x) ((x)<<12) 130 131#define AD7877_READ_CHAN(x) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_SER | \ 132 AD7877_MODE_SCC | AD7877_CHANADD(AD7877_REG_ ## x) | \ 133 AD7877_READADD(AD7877_REG_ ## x)) 134 135#define AD7877_MM_SEQUENCE (AD7877_SEQ_YPLUS_BIT | AD7877_SEQ_XPLUS_BIT | \ 136 AD7877_SEQ_Z2_BIT | AD7877_SEQ_Z1_BIT) 137 138/* 139 * Non-touchscreen sensors only use single-ended conversions. 140 */ 141 142struct ser_req { 143 u16 reset; 144 u16 ref_on; 145 u16 command; 146 struct spi_message msg; 147 struct spi_transfer xfer[6]; 148 149 /* 150 * DMA (thus cache coherency maintenance) requires the 151 * transfer buffers to live in their own cache lines. 152 */ 153 u16 sample ____cacheline_aligned; 154}; 155 156struct ad7877 { 157 struct input_dev *input; 158 char phys[32]; 159 160 struct spi_device *spi; 161 u16 model; 162 u16 vref_delay_usecs; 163 u16 x_plate_ohms; 164 u16 pressure_max; 165 166 u16 cmd_crtl1; 167 u16 cmd_crtl2; 168 u16 cmd_dummy; 169 u16 dac; 170 171 u8 stopacq_polarity; 172 u8 first_conversion_delay; 173 u8 acquisition_time; 174 u8 averaging; 175 u8 pen_down_acc_interval; 176 177 struct spi_transfer xfer[AD7877_NR_SENSE + 2]; 178 struct spi_message msg; 179 180 struct mutex mutex; 181 bool disabled; /* P: mutex */ 182 bool gpio3; /* P: mutex */ 183 bool gpio4; /* P: mutex */ 184 185 spinlock_t lock; 186 struct timer_list timer; /* P: lock */ 187 188 /* 189 * DMA (thus cache coherency maintenance) requires the 190 * transfer buffers to live in their own cache lines. 191 */ 192 u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned; 193}; 194 195static bool gpio3; 196module_param(gpio3, bool, 0); 197MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3"); 198 199static int ad7877_read(struct spi_device *spi, u16 reg) 200{ 201 struct ser_req *req; 202 int status, ret; 203 204 req = kzalloc(sizeof *req, GFP_KERNEL); 205 if (!req) 206 return -ENOMEM; 207 208 spi_message_init(&req->msg); 209 210 req->command = (u16) (AD7877_WRITEADD(AD7877_REG_CTRL1) | 211 AD7877_READADD(reg)); 212 req->xfer[0].tx_buf = &req->command; 213 req->xfer[0].len = 2; 214 req->xfer[0].cs_change = 1; 215 216 req->xfer[1].rx_buf = &req->sample; 217 req->xfer[1].len = 2; 218 219 spi_message_add_tail(&req->xfer[0], &req->msg); 220 spi_message_add_tail(&req->xfer[1], &req->msg); 221 222 status = spi_sync(spi, &req->msg); 223 ret = status ? : req->sample; 224 225 kfree(req); 226 227 return ret; 228} 229 230static int ad7877_write(struct spi_device *spi, u16 reg, u16 val) 231{ 232 struct ser_req *req; 233 int status; 234 235 req = kzalloc(sizeof *req, GFP_KERNEL); 236 if (!req) 237 return -ENOMEM; 238 239 spi_message_init(&req->msg); 240 241 req->command = (u16) (AD7877_WRITEADD(reg) | (val & MAX_12BIT)); 242 req->xfer[0].tx_buf = &req->command; 243 req->xfer[0].len = 2; 244 245 spi_message_add_tail(&req->xfer[0], &req->msg); 246 247 status = spi_sync(spi, &req->msg); 248 249 kfree(req); 250 251 return status; 252} 253 254static int ad7877_read_adc(struct spi_device *spi, unsigned command) 255{ 256 struct ad7877 *ts = spi_get_drvdata(spi); 257 struct ser_req *req; 258 int status; 259 int sample; 260 int i; 261 262 req = kzalloc(sizeof *req, GFP_KERNEL); 263 if (!req) 264 return -ENOMEM; 265 266 spi_message_init(&req->msg); 267 268 /* activate reference, so it has time to settle; */ 269 req->ref_on = AD7877_WRITEADD(AD7877_REG_CTRL2) | 270 AD7877_POL(ts->stopacq_polarity) | 271 AD7877_AVG(0) | AD7877_PM(2) | AD7877_TMR(0) | 272 AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(0); 273 274 req->reset = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_MODE_NOC; 275 276 req->command = (u16) command; 277 278 req->xfer[0].tx_buf = &req->reset; 279 req->xfer[0].len = 2; 280 req->xfer[0].cs_change = 1; 281 282 req->xfer[1].tx_buf = &req->ref_on; 283 req->xfer[1].len = 2; 284 req->xfer[1].delay.value = ts->vref_delay_usecs; 285 req->xfer[1].delay.unit = SPI_DELAY_UNIT_USECS; 286 req->xfer[1].cs_change = 1; 287 288 req->xfer[2].tx_buf = &req->command; 289 req->xfer[2].len = 2; 290 req->xfer[2].delay.value = ts->vref_delay_usecs; 291 req->xfer[2].delay.unit = SPI_DELAY_UNIT_USECS; 292 req->xfer[2].cs_change = 1; 293 294 req->xfer[3].rx_buf = &req->sample; 295 req->xfer[3].len = 2; 296 req->xfer[3].cs_change = 1; 297 298 req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/ 299 req->xfer[4].len = 2; 300 req->xfer[4].cs_change = 1; 301 302 req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/ 303 req->xfer[5].len = 2; 304 305 /* group all the transfers together, so we can't interfere with 306 * reading touchscreen state; disable penirq while sampling 307 */ 308 for (i = 0; i < 6; i++) 309 spi_message_add_tail(&req->xfer[i], &req->msg); 310 311 status = spi_sync(spi, &req->msg); 312 sample = req->sample; 313 314 kfree(req); 315 316 return status ? : sample; 317} 318 319static int ad7877_process_data(struct ad7877 *ts) 320{ 321 struct input_dev *input_dev = ts->input; 322 unsigned Rt; 323 u16 x, y, z1, z2; 324 325 x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT; 326 y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT; 327 z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT; 328 z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT; 329 330 /* 331 * The samples processed here are already preprocessed by the AD7877. 332 * The preprocessing function consists of an averaging filter. 333 * The combination of 'first conversion delay' and averaging provides a robust solution, 334 * discarding the spurious noise in the signal and keeping only the data of interest. 335 * The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h) 336 * Other user-programmable conversion controls include variable acquisition time, 337 * and first conversion delay. Up to 16 averages can be taken per conversion. 338 */ 339 340 if (likely(x && z1)) { 341 /* compute touch pressure resistance using equation #1 */ 342 Rt = (z2 - z1) * x * ts->x_plate_ohms; 343 Rt /= z1; 344 Rt = (Rt + 2047) >> 12; 345 346 /* 347 * Sample found inconsistent, pressure is beyond 348 * the maximum. Don't report it to user space. 349 */ 350 if (Rt > ts->pressure_max) 351 return -EINVAL; 352 353 if (!timer_pending(&ts->timer)) 354 input_report_key(input_dev, BTN_TOUCH, 1); 355 356 input_report_abs(input_dev, ABS_X, x); 357 input_report_abs(input_dev, ABS_Y, y); 358 input_report_abs(input_dev, ABS_PRESSURE, Rt); 359 input_sync(input_dev); 360 361 return 0; 362 } 363 364 return -EINVAL; 365} 366 367static inline void ad7877_ts_event_release(struct ad7877 *ts) 368{ 369 struct input_dev *input_dev = ts->input; 370 371 input_report_abs(input_dev, ABS_PRESSURE, 0); 372 input_report_key(input_dev, BTN_TOUCH, 0); 373 input_sync(input_dev); 374} 375 376static void ad7877_timer(struct timer_list *t) 377{ 378 struct ad7877 *ts = from_timer(ts, t, timer); 379 unsigned long flags; 380 381 spin_lock_irqsave(&ts->lock, flags); 382 ad7877_ts_event_release(ts); 383 spin_unlock_irqrestore(&ts->lock, flags); 384} 385 386static irqreturn_t ad7877_irq(int irq, void *handle) 387{ 388 struct ad7877 *ts = handle; 389 unsigned long flags; 390 int error; 391 392 error = spi_sync(ts->spi, &ts->msg); 393 if (error) { 394 dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); 395 goto out; 396 } 397 398 spin_lock_irqsave(&ts->lock, flags); 399 error = ad7877_process_data(ts); 400 if (!error) 401 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT); 402 spin_unlock_irqrestore(&ts->lock, flags); 403 404out: 405 return IRQ_HANDLED; 406} 407 408static void ad7877_disable(void *data) 409{ 410 struct ad7877 *ts = data; 411 412 mutex_lock(&ts->mutex); 413 414 if (!ts->disabled) { 415 ts->disabled = true; 416 disable_irq(ts->spi->irq); 417 418 if (del_timer_sync(&ts->timer)) 419 ad7877_ts_event_release(ts); 420 } 421 422 /* 423 * We know the chip's in lowpower mode since we always 424 * leave it that way after every request 425 */ 426 427 mutex_unlock(&ts->mutex); 428} 429 430static void ad7877_enable(struct ad7877 *ts) 431{ 432 mutex_lock(&ts->mutex); 433 434 if (ts->disabled) { 435 ts->disabled = false; 436 enable_irq(ts->spi->irq); 437 } 438 439 mutex_unlock(&ts->mutex); 440} 441 442#define SHOW(name) static ssize_t \ 443name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ 444{ \ 445 struct ad7877 *ts = dev_get_drvdata(dev); \ 446 ssize_t v = ad7877_read_adc(ts->spi, \ 447 AD7877_READ_CHAN(name)); \ 448 if (v < 0) \ 449 return v; \ 450 return sprintf(buf, "%u\n", (unsigned) v); \ 451} \ 452static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); 453 454SHOW(aux1) 455SHOW(aux2) 456SHOW(aux3) 457SHOW(bat1) 458SHOW(bat2) 459SHOW(temp1) 460SHOW(temp2) 461 462static ssize_t ad7877_disable_show(struct device *dev, 463 struct device_attribute *attr, char *buf) 464{ 465 struct ad7877 *ts = dev_get_drvdata(dev); 466 467 return sprintf(buf, "%u\n", ts->disabled); 468} 469 470static ssize_t ad7877_disable_store(struct device *dev, 471 struct device_attribute *attr, 472 const char *buf, size_t count) 473{ 474 struct ad7877 *ts = dev_get_drvdata(dev); 475 unsigned int val; 476 int error; 477 478 error = kstrtouint(buf, 10, &val); 479 if (error) 480 return error; 481 482 if (val) 483 ad7877_disable(ts); 484 else 485 ad7877_enable(ts); 486 487 return count; 488} 489 490static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store); 491 492static ssize_t ad7877_dac_show(struct device *dev, 493 struct device_attribute *attr, char *buf) 494{ 495 struct ad7877 *ts = dev_get_drvdata(dev); 496 497 return sprintf(buf, "%u\n", ts->dac); 498} 499 500static ssize_t ad7877_dac_store(struct device *dev, 501 struct device_attribute *attr, 502 const char *buf, size_t count) 503{ 504 struct ad7877 *ts = dev_get_drvdata(dev); 505 unsigned int val; 506 int error; 507 508 error = kstrtouint(buf, 10, &val); 509 if (error) 510 return error; 511 512 mutex_lock(&ts->mutex); 513 ts->dac = val & 0xFF; 514 ad7877_write(ts->spi, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF); 515 mutex_unlock(&ts->mutex); 516 517 return count; 518} 519 520static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store); 521 522static ssize_t ad7877_gpio3_show(struct device *dev, 523 struct device_attribute *attr, char *buf) 524{ 525 struct ad7877 *ts = dev_get_drvdata(dev); 526 527 return sprintf(buf, "%u\n", ts->gpio3); 528} 529 530static ssize_t ad7877_gpio3_store(struct device *dev, 531 struct device_attribute *attr, 532 const char *buf, size_t count) 533{ 534 struct ad7877 *ts = dev_get_drvdata(dev); 535 unsigned int val; 536 int error; 537 538 error = kstrtouint(buf, 10, &val); 539 if (error) 540 return error; 541 542 mutex_lock(&ts->mutex); 543 ts->gpio3 = !!val; 544 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | 545 (ts->gpio4 << 4) | (ts->gpio3 << 5)); 546 mutex_unlock(&ts->mutex); 547 548 return count; 549} 550 551static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store); 552 553static ssize_t ad7877_gpio4_show(struct device *dev, 554 struct device_attribute *attr, char *buf) 555{ 556 struct ad7877 *ts = dev_get_drvdata(dev); 557 558 return sprintf(buf, "%u\n", ts->gpio4); 559} 560 561static ssize_t ad7877_gpio4_store(struct device *dev, 562 struct device_attribute *attr, 563 const char *buf, size_t count) 564{ 565 struct ad7877 *ts = dev_get_drvdata(dev); 566 unsigned int val; 567 int error; 568 569 error = kstrtouint(buf, 10, &val); 570 if (error) 571 return error; 572 573 mutex_lock(&ts->mutex); 574 ts->gpio4 = !!val; 575 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | 576 (ts->gpio4 << 4) | (ts->gpio3 << 5)); 577 mutex_unlock(&ts->mutex); 578 579 return count; 580} 581 582static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store); 583 584static struct attribute *ad7877_attributes[] = { 585 &dev_attr_temp1.attr, 586 &dev_attr_temp2.attr, 587 &dev_attr_aux1.attr, 588 &dev_attr_aux2.attr, 589 &dev_attr_aux3.attr, 590 &dev_attr_bat1.attr, 591 &dev_attr_bat2.attr, 592 &dev_attr_disable.attr, 593 &dev_attr_dac.attr, 594 &dev_attr_gpio3.attr, 595 &dev_attr_gpio4.attr, 596 NULL 597}; 598 599static umode_t ad7877_attr_is_visible(struct kobject *kobj, 600 struct attribute *attr, int n) 601{ 602 umode_t mode = attr->mode; 603 604 if (attr == &dev_attr_aux3.attr) { 605 if (gpio3) 606 mode = 0; 607 } else if (attr == &dev_attr_gpio3.attr) { 608 if (!gpio3) 609 mode = 0; 610 } 611 612 return mode; 613} 614 615static const struct attribute_group ad7877_group = { 616 .is_visible = ad7877_attr_is_visible, 617 .attrs = ad7877_attributes, 618}; 619__ATTRIBUTE_GROUPS(ad7877); 620 621static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts) 622{ 623 struct spi_message *m; 624 int i; 625 626 ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) | 627 AD7877_POL(ts->stopacq_polarity) | 628 AD7877_AVG(ts->averaging) | AD7877_PM(1) | 629 AD7877_TMR(ts->pen_down_acc_interval) | 630 AD7877_ACQ(ts->acquisition_time) | 631 AD7877_FCD(ts->first_conversion_delay); 632 633 ad7877_write(spi, AD7877_REG_CTRL2, ts->cmd_crtl2); 634 635 ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) | 636 AD7877_READADD(AD7877_REG_XPLUS-1) | 637 AD7877_MODE_SEQ1 | AD7877_DFR; 638 639 ad7877_write(spi, AD7877_REG_CTRL1, ts->cmd_crtl1); 640 641 ts->cmd_dummy = 0; 642 643 m = &ts->msg; 644 645 spi_message_init(m); 646 647 m->context = ts; 648 649 ts->xfer[0].tx_buf = &ts->cmd_crtl1; 650 ts->xfer[0].len = 2; 651 ts->xfer[0].cs_change = 1; 652 653 spi_message_add_tail(&ts->xfer[0], m); 654 655 ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */ 656 ts->xfer[1].len = 2; 657 ts->xfer[1].cs_change = 1; 658 659 spi_message_add_tail(&ts->xfer[1], m); 660 661 for (i = 0; i < AD7877_NR_SENSE; i++) { 662 ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i]; 663 ts->xfer[i + 2].len = 2; 664 if (i < (AD7877_NR_SENSE - 1)) 665 ts->xfer[i + 2].cs_change = 1; 666 spi_message_add_tail(&ts->xfer[i + 2], m); 667 } 668} 669 670static int ad7877_probe(struct spi_device *spi) 671{ 672 struct ad7877 *ts; 673 struct input_dev *input_dev; 674 struct ad7877_platform_data *pdata = dev_get_platdata(&spi->dev); 675 int err; 676 u16 verify; 677 678 if (!spi->irq) { 679 dev_dbg(&spi->dev, "no IRQ?\n"); 680 return -ENODEV; 681 } 682 683 if (!pdata) { 684 dev_dbg(&spi->dev, "no platform data?\n"); 685 return -ENODEV; 686 } 687 688 /* don't exceed max specified SPI CLK frequency */ 689 if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { 690 dev_dbg(&spi->dev, "SPI CLK %d Hz?\n",spi->max_speed_hz); 691 return -EINVAL; 692 } 693 694 spi->bits_per_word = 16; 695 err = spi_setup(spi); 696 if (err) { 697 dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n"); 698 return err; 699 } 700 701 ts = devm_kzalloc(&spi->dev, sizeof(struct ad7877), GFP_KERNEL); 702 if (!ts) 703 return -ENOMEM; 704 705 input_dev = devm_input_allocate_device(&spi->dev); 706 if (!input_dev) 707 return -ENOMEM; 708 709 err = devm_add_action_or_reset(&spi->dev, ad7877_disable, ts); 710 if (err) 711 return err; 712 713 spi_set_drvdata(spi, ts); 714 ts->spi = spi; 715 ts->input = input_dev; 716 717 timer_setup(&ts->timer, ad7877_timer, 0); 718 mutex_init(&ts->mutex); 719 spin_lock_init(&ts->lock); 720 721 ts->model = pdata->model ? : 7877; 722 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; 723 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; 724 ts->pressure_max = pdata->pressure_max ? : ~0; 725 726 ts->stopacq_polarity = pdata->stopacq_polarity; 727 ts->first_conversion_delay = pdata->first_conversion_delay; 728 ts->acquisition_time = pdata->acquisition_time; 729 ts->averaging = pdata->averaging; 730 ts->pen_down_acc_interval = pdata->pen_down_acc_interval; 731 732 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); 733 734 input_dev->name = "AD7877 Touchscreen"; 735 input_dev->phys = ts->phys; 736 input_dev->dev.parent = &spi->dev; 737 738 __set_bit(EV_KEY, input_dev->evbit); 739 __set_bit(BTN_TOUCH, input_dev->keybit); 740 __set_bit(EV_ABS, input_dev->evbit); 741 __set_bit(ABS_X, input_dev->absbit); 742 __set_bit(ABS_Y, input_dev->absbit); 743 __set_bit(ABS_PRESSURE, input_dev->absbit); 744 745 input_set_abs_params(input_dev, ABS_X, 746 pdata->x_min ? : 0, 747 pdata->x_max ? : MAX_12BIT, 748 0, 0); 749 input_set_abs_params(input_dev, ABS_Y, 750 pdata->y_min ? : 0, 751 pdata->y_max ? : MAX_12BIT, 752 0, 0); 753 input_set_abs_params(input_dev, ABS_PRESSURE, 754 pdata->pressure_min, pdata->pressure_max, 0, 0); 755 756 ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE); 757 758 verify = ad7877_read(spi, AD7877_REG_SEQ1); 759 760 if (verify != AD7877_MM_SEQUENCE) { 761 dev_err(&spi->dev, "%s: Failed to probe %s\n", 762 dev_name(&spi->dev), input_dev->name); 763 return -ENODEV; 764 } 765 766 if (gpio3) 767 ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF); 768 769 ad7877_setup_ts_def_msg(spi, ts); 770 771 /* Request AD7877 /DAV GPIO interrupt */ 772 773 err = devm_request_threaded_irq(&spi->dev, spi->irq, NULL, ad7877_irq, 774 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 775 spi->dev.driver->name, ts); 776 if (err) { 777 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); 778 return err; 779 } 780 781 err = input_register_device(input_dev); 782 if (err) 783 return err; 784 785 return 0; 786} 787 788static int ad7877_suspend(struct device *dev) 789{ 790 struct ad7877 *ts = dev_get_drvdata(dev); 791 792 ad7877_disable(ts); 793 794 return 0; 795} 796 797static int ad7877_resume(struct device *dev) 798{ 799 struct ad7877 *ts = dev_get_drvdata(dev); 800 801 ad7877_enable(ts); 802 803 return 0; 804} 805 806static DEFINE_SIMPLE_DEV_PM_OPS(ad7877_pm, ad7877_suspend, ad7877_resume); 807 808static struct spi_driver ad7877_driver = { 809 .driver = { 810 .name = "ad7877", 811 .dev_groups = ad7877_groups, 812 .pm = pm_sleep_ptr(&ad7877_pm), 813 }, 814 .probe = ad7877_probe, 815}; 816 817module_spi_driver(ad7877_driver); 818 819MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 820MODULE_DESCRIPTION("AD7877 touchscreen Driver"); 821MODULE_LICENSE("GPL"); 822MODULE_ALIAS("spi:ad7877"); 823