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 87 enum { 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 */ 141 142 struct 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 }; 155 156 struct 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 }; 194 195 static bool gpio3; 196 module_param(gpio3, bool, 0); 197 MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3"); 198 199 static 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 } 229 230 static 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 } 253 254 static 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_usecs = ts->vref_delay_usecs; 285 req->xfer[1].cs_change = 1; 286 287 req->xfer[2].tx_buf = &req->command; 288 req->xfer[2].len = 2; 289 req->xfer[2].delay_usecs = ts->vref_delay_usecs; 290 req->xfer[2].cs_change = 1; 291 292 req->xfer[3].rx_buf = &req->sample; 293 req->xfer[3].len = 2; 294 req->xfer[3].cs_change = 1; 295 296 req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/ 297 req->xfer[4].len = 2; 298 req->xfer[4].cs_change = 1; 299 300 req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/ 301 req->xfer[5].len = 2; 302 303 /* group all the transfers together, so we can't interfere with 304 * reading touchscreen state; disable penirq while sampling 305 */ 306 for (i = 0; i < 6; i++) 307 spi_message_add_tail(&req->xfer[i], &req->msg); 308 309 status = spi_sync(spi, &req->msg); 310 sample = req->sample; 311 312 kfree(req); 313 314 return status ? : sample; 315 } 316 317 static int ad7877_process_data(struct ad7877 *ts) 318 { 319 struct input_dev *input_dev = ts->input; 320 unsigned Rt; 321 u16 x, y, z1, z2; 322 323 x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT; 324 y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT; 325 z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT; 326 z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT; 327 328 /* 329 * The samples processed here are already preprocessed by the AD7877. 330 * The preprocessing function consists of an averaging filter. 331 * The combination of 'first conversion delay' and averaging provides a robust solution, 332 * discarding the spurious noise in the signal and keeping only the data of interest. 333 * The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h) 334 * Other user-programmable conversion controls include variable acquisition time, 335 * and first conversion delay. Up to 16 averages can be taken per conversion. 336 */ 337 338 if (likely(x && z1)) { 339 /* compute touch pressure resistance using equation #1 */ 340 Rt = (z2 - z1) * x * ts->x_plate_ohms; 341 Rt /= z1; 342 Rt = (Rt + 2047) >> 12; 343 344 /* 345 * Sample found inconsistent, pressure is beyond 346 * the maximum. Don't report it to user space. 347 */ 348 if (Rt > ts->pressure_max) 349 return -EINVAL; 350 351 if (!timer_pending(&ts->timer)) 352 input_report_key(input_dev, BTN_TOUCH, 1); 353 354 input_report_abs(input_dev, ABS_X, x); 355 input_report_abs(input_dev, ABS_Y, y); 356 input_report_abs(input_dev, ABS_PRESSURE, Rt); 357 input_sync(input_dev); 358 359 return 0; 360 } 361 362 return -EINVAL; 363 } 364 365 static inline void ad7877_ts_event_release(struct ad7877 *ts) 366 { 367 struct input_dev *input_dev = ts->input; 368 369 input_report_abs(input_dev, ABS_PRESSURE, 0); 370 input_report_key(input_dev, BTN_TOUCH, 0); 371 input_sync(input_dev); 372 } 373 374 static void ad7877_timer(struct timer_list *t) 375 { 376 struct ad7877 *ts = from_timer(ts, t, timer); 377 unsigned long flags; 378 379 spin_lock_irqsave(&ts->lock, flags); 380 ad7877_ts_event_release(ts); 381 spin_unlock_irqrestore(&ts->lock, flags); 382 } 383 384 static irqreturn_t ad7877_irq(int irq, void *handle) 385 { 386 struct ad7877 *ts = handle; 387 unsigned long flags; 388 int error; 389 390 error = spi_sync(ts->spi, &ts->msg); 391 if (error) { 392 dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); 393 goto out; 394 } 395 396 spin_lock_irqsave(&ts->lock, flags); 397 error = ad7877_process_data(ts); 398 if (!error) 399 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT); 400 spin_unlock_irqrestore(&ts->lock, flags); 401 402 out: 403 return IRQ_HANDLED; 404 } 405 406 static void ad7877_disable(void *data) 407 { 408 struct ad7877 *ts = data; 409 410 mutex_lock(&ts->mutex); 411 412 if (!ts->disabled) { 413 ts->disabled = true; 414 disable_irq(ts->spi->irq); 415 416 if (del_timer_sync(&ts->timer)) 417 ad7877_ts_event_release(ts); 418 } 419 420 /* 421 * We know the chip's in lowpower mode since we always 422 * leave it that way after every request 423 */ 424 425 mutex_unlock(&ts->mutex); 426 } 427 428 static void ad7877_enable(struct ad7877 *ts) 429 { 430 mutex_lock(&ts->mutex); 431 432 if (ts->disabled) { 433 ts->disabled = false; 434 enable_irq(ts->spi->irq); 435 } 436 437 mutex_unlock(&ts->mutex); 438 } 439 440 #define SHOW(name) static ssize_t \ 441 name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ 442 { \ 443 struct ad7877 *ts = dev_get_drvdata(dev); \ 444 ssize_t v = ad7877_read_adc(ts->spi, \ 445 AD7877_READ_CHAN(name)); \ 446 if (v < 0) \ 447 return v; \ 448 return sprintf(buf, "%u\n", (unsigned) v); \ 449 } \ 450 static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); 451 452 SHOW(aux1) 453 SHOW(aux2) 454 SHOW(aux3) 455 SHOW(bat1) 456 SHOW(bat2) 457 SHOW(temp1) 458 SHOW(temp2) 459 460 static ssize_t ad7877_disable_show(struct device *dev, 461 struct device_attribute *attr, char *buf) 462 { 463 struct ad7877 *ts = dev_get_drvdata(dev); 464 465 return sprintf(buf, "%u\n", ts->disabled); 466 } 467 468 static ssize_t ad7877_disable_store(struct device *dev, 469 struct device_attribute *attr, 470 const char *buf, size_t count) 471 { 472 struct ad7877 *ts = dev_get_drvdata(dev); 473 unsigned int val; 474 int error; 475 476 error = kstrtouint(buf, 10, &val); 477 if (error) 478 return error; 479 480 if (val) 481 ad7877_disable(ts); 482 else 483 ad7877_enable(ts); 484 485 return count; 486 } 487 488 static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store); 489 490 static ssize_t ad7877_dac_show(struct device *dev, 491 struct device_attribute *attr, char *buf) 492 { 493 struct ad7877 *ts = dev_get_drvdata(dev); 494 495 return sprintf(buf, "%u\n", ts->dac); 496 } 497 498 static ssize_t ad7877_dac_store(struct device *dev, 499 struct device_attribute *attr, 500 const char *buf, size_t count) 501 { 502 struct ad7877 *ts = dev_get_drvdata(dev); 503 unsigned int val; 504 int error; 505 506 error = kstrtouint(buf, 10, &val); 507 if (error) 508 return error; 509 510 mutex_lock(&ts->mutex); 511 ts->dac = val & 0xFF; 512 ad7877_write(ts->spi, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF); 513 mutex_unlock(&ts->mutex); 514 515 return count; 516 } 517 518 static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store); 519 520 static ssize_t ad7877_gpio3_show(struct device *dev, 521 struct device_attribute *attr, char *buf) 522 { 523 struct ad7877 *ts = dev_get_drvdata(dev); 524 525 return sprintf(buf, "%u\n", ts->gpio3); 526 } 527 528 static ssize_t ad7877_gpio3_store(struct device *dev, 529 struct device_attribute *attr, 530 const char *buf, size_t count) 531 { 532 struct ad7877 *ts = dev_get_drvdata(dev); 533 unsigned int val; 534 int error; 535 536 error = kstrtouint(buf, 10, &val); 537 if (error) 538 return error; 539 540 mutex_lock(&ts->mutex); 541 ts->gpio3 = !!val; 542 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | 543 (ts->gpio4 << 4) | (ts->gpio3 << 5)); 544 mutex_unlock(&ts->mutex); 545 546 return count; 547 } 548 549 static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store); 550 551 static ssize_t ad7877_gpio4_show(struct device *dev, 552 struct device_attribute *attr, char *buf) 553 { 554 struct ad7877 *ts = dev_get_drvdata(dev); 555 556 return sprintf(buf, "%u\n", ts->gpio4); 557 } 558 559 static ssize_t ad7877_gpio4_store(struct device *dev, 560 struct device_attribute *attr, 561 const char *buf, size_t count) 562 { 563 struct ad7877 *ts = dev_get_drvdata(dev); 564 unsigned int val; 565 int error; 566 567 error = kstrtouint(buf, 10, &val); 568 if (error) 569 return error; 570 571 mutex_lock(&ts->mutex); 572 ts->gpio4 = !!val; 573 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | 574 (ts->gpio4 << 4) | (ts->gpio3 << 5)); 575 mutex_unlock(&ts->mutex); 576 577 return count; 578 } 579 580 static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store); 581 582 static struct attribute *ad7877_attributes[] = { 583 &dev_attr_temp1.attr, 584 &dev_attr_temp2.attr, 585 &dev_attr_aux1.attr, 586 &dev_attr_aux2.attr, 587 &dev_attr_aux3.attr, 588 &dev_attr_bat1.attr, 589 &dev_attr_bat2.attr, 590 &dev_attr_disable.attr, 591 &dev_attr_dac.attr, 592 &dev_attr_gpio3.attr, 593 &dev_attr_gpio4.attr, 594 NULL 595 }; 596 597 static umode_t ad7877_attr_is_visible(struct kobject *kobj, 598 struct attribute *attr, int n) 599 { 600 umode_t mode = attr->mode; 601 602 if (attr == &dev_attr_aux3.attr) { 603 if (gpio3) 604 mode = 0; 605 } else if (attr == &dev_attr_gpio3.attr) { 606 if (!gpio3) 607 mode = 0; 608 } 609 610 return mode; 611 } 612 613 static const struct attribute_group ad7877_attr_group = { 614 .is_visible = ad7877_attr_is_visible, 615 .attrs = ad7877_attributes, 616 }; 617 618 static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts) 619 { 620 struct spi_message *m; 621 int i; 622 623 ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) | 624 AD7877_POL(ts->stopacq_polarity) | 625 AD7877_AVG(ts->averaging) | AD7877_PM(1) | 626 AD7877_TMR(ts->pen_down_acc_interval) | 627 AD7877_ACQ(ts->acquisition_time) | 628 AD7877_FCD(ts->first_conversion_delay); 629 630 ad7877_write(spi, AD7877_REG_CTRL2, ts->cmd_crtl2); 631 632 ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) | 633 AD7877_READADD(AD7877_REG_XPLUS-1) | 634 AD7877_MODE_SEQ1 | AD7877_DFR; 635 636 ad7877_write(spi, AD7877_REG_CTRL1, ts->cmd_crtl1); 637 638 ts->cmd_dummy = 0; 639 640 m = &ts->msg; 641 642 spi_message_init(m); 643 644 m->context = ts; 645 646 ts->xfer[0].tx_buf = &ts->cmd_crtl1; 647 ts->xfer[0].len = 2; 648 ts->xfer[0].cs_change = 1; 649 650 spi_message_add_tail(&ts->xfer[0], m); 651 652 ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */ 653 ts->xfer[1].len = 2; 654 ts->xfer[1].cs_change = 1; 655 656 spi_message_add_tail(&ts->xfer[1], m); 657 658 for (i = 0; i < AD7877_NR_SENSE; i++) { 659 ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i]; 660 ts->xfer[i + 2].len = 2; 661 if (i < (AD7877_NR_SENSE - 1)) 662 ts->xfer[i + 2].cs_change = 1; 663 spi_message_add_tail(&ts->xfer[i + 2], m); 664 } 665 } 666 667 static int ad7877_probe(struct spi_device *spi) 668 { 669 struct ad7877 *ts; 670 struct input_dev *input_dev; 671 struct ad7877_platform_data *pdata = dev_get_platdata(&spi->dev); 672 int err; 673 u16 verify; 674 675 if (!spi->irq) { 676 dev_dbg(&spi->dev, "no IRQ?\n"); 677 return -ENODEV; 678 } 679 680 if (!pdata) { 681 dev_dbg(&spi->dev, "no platform data?\n"); 682 return -ENODEV; 683 } 684 685 /* don't exceed max specified SPI CLK frequency */ 686 if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { 687 dev_dbg(&spi->dev, "SPI CLK %d Hz?\n",spi->max_speed_hz); 688 return -EINVAL; 689 } 690 691 spi->bits_per_word = 16; 692 err = spi_setup(spi); 693 if (err) { 694 dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n"); 695 return err; 696 } 697 698 ts = devm_kzalloc(&spi->dev, sizeof(struct ad7877), GFP_KERNEL); 699 if (!ts) 700 return -ENOMEM; 701 702 input_dev = devm_input_allocate_device(&spi->dev); 703 if (!input_dev) 704 return -ENOMEM; 705 706 err = devm_add_action_or_reset(&spi->dev, ad7877_disable, ts); 707 if (err) 708 return err; 709 710 spi_set_drvdata(spi, ts); 711 ts->spi = spi; 712 ts->input = input_dev; 713 714 timer_setup(&ts->timer, ad7877_timer, 0); 715 mutex_init(&ts->mutex); 716 spin_lock_init(&ts->lock); 717 718 ts->model = pdata->model ? : 7877; 719 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; 720 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; 721 ts->pressure_max = pdata->pressure_max ? : ~0; 722 723 ts->stopacq_polarity = pdata->stopacq_polarity; 724 ts->first_conversion_delay = pdata->first_conversion_delay; 725 ts->acquisition_time = pdata->acquisition_time; 726 ts->averaging = pdata->averaging; 727 ts->pen_down_acc_interval = pdata->pen_down_acc_interval; 728 729 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); 730 731 input_dev->name = "AD7877 Touchscreen"; 732 input_dev->phys = ts->phys; 733 input_dev->dev.parent = &spi->dev; 734 735 __set_bit(EV_KEY, input_dev->evbit); 736 __set_bit(BTN_TOUCH, input_dev->keybit); 737 __set_bit(EV_ABS, input_dev->evbit); 738 __set_bit(ABS_X, input_dev->absbit); 739 __set_bit(ABS_Y, input_dev->absbit); 740 __set_bit(ABS_PRESSURE, input_dev->absbit); 741 742 input_set_abs_params(input_dev, ABS_X, 743 pdata->x_min ? : 0, 744 pdata->x_max ? : MAX_12BIT, 745 0, 0); 746 input_set_abs_params(input_dev, ABS_Y, 747 pdata->y_min ? : 0, 748 pdata->y_max ? : MAX_12BIT, 749 0, 0); 750 input_set_abs_params(input_dev, ABS_PRESSURE, 751 pdata->pressure_min, pdata->pressure_max, 0, 0); 752 753 ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE); 754 755 verify = ad7877_read(spi, AD7877_REG_SEQ1); 756 757 if (verify != AD7877_MM_SEQUENCE) { 758 dev_err(&spi->dev, "%s: Failed to probe %s\n", 759 dev_name(&spi->dev), input_dev->name); 760 return -ENODEV; 761 } 762 763 if (gpio3) 764 ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF); 765 766 ad7877_setup_ts_def_msg(spi, ts); 767 768 /* Request AD7877 /DAV GPIO interrupt */ 769 770 err = devm_request_threaded_irq(&spi->dev, spi->irq, NULL, ad7877_irq, 771 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 772 spi->dev.driver->name, ts); 773 if (err) { 774 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); 775 return err; 776 } 777 778 err = devm_device_add_group(&spi->dev, &ad7877_attr_group); 779 if (err) 780 return err; 781 782 err = input_register_device(input_dev); 783 if (err) 784 return err; 785 786 return 0; 787 } 788 789 static int __maybe_unused ad7877_suspend(struct device *dev) 790 { 791 struct ad7877 *ts = dev_get_drvdata(dev); 792 793 ad7877_disable(ts); 794 795 return 0; 796 } 797 798 static int __maybe_unused ad7877_resume(struct device *dev) 799 { 800 struct ad7877 *ts = dev_get_drvdata(dev); 801 802 ad7877_enable(ts); 803 804 return 0; 805 } 806 807 static SIMPLE_DEV_PM_OPS(ad7877_pm, ad7877_suspend, ad7877_resume); 808 809 static struct spi_driver ad7877_driver = { 810 .driver = { 811 .name = "ad7877", 812 .pm = &ad7877_pm, 813 }, 814 .probe = ad7877_probe, 815 }; 816 817 module_spi_driver(ad7877_driver); 818 819 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 820 MODULE_DESCRIPTION("AD7877 touchscreen Driver"); 821 MODULE_LICENSE("GPL"); 822 MODULE_ALIAS("spi:ad7877"); 823