1 /* 2 * Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc. 3 * 4 * Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver 5 * Based on: ads7846.c 6 * 7 * Bugs: Enter bugs at http://blackfin.uclinux.org/ 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, see the file COPYING, or write 21 * to the Free Software Foundation, Inc., 22 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 23 * 24 * History: 25 * Copyright (c) 2005 David Brownell 26 * Copyright (c) 2006 Nokia Corporation 27 * Various changes: Imre Deak <imre.deak@nokia.com> 28 * 29 * Using code from: 30 * - corgi_ts.c 31 * Copyright (C) 2004-2005 Richard Purdie 32 * - omap_ts.[hc], ads7846.h, ts_osk.c 33 * Copyright (C) 2002 MontaVista Software 34 * Copyright (C) 2004 Texas Instruments 35 * Copyright (C) 2005 Dirk Behme 36 */ 37 38 39 #include <linux/device.h> 40 #include <linux/init.h> 41 #include <linux/delay.h> 42 #include <linux/input.h> 43 #include <linux/interrupt.h> 44 #include <linux/slab.h> 45 #include <linux/spi/spi.h> 46 #include <linux/spi/ad7877.h> 47 #include <asm/irq.h> 48 49 #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100) 50 51 #define MAX_SPI_FREQ_HZ 20000000 52 #define MAX_12BIT ((1<<12)-1) 53 54 #define AD7877_REG_ZEROS 0 55 #define AD7877_REG_CTRL1 1 56 #define AD7877_REG_CTRL2 2 57 #define AD7877_REG_ALERT 3 58 #define AD7877_REG_AUX1HIGH 4 59 #define AD7877_REG_AUX1LOW 5 60 #define AD7877_REG_BAT1HIGH 6 61 #define AD7877_REG_BAT1LOW 7 62 #define AD7877_REG_BAT2HIGH 8 63 #define AD7877_REG_BAT2LOW 9 64 #define AD7877_REG_TEMP1HIGH 10 65 #define AD7877_REG_TEMP1LOW 11 66 #define AD7877_REG_SEQ0 12 67 #define AD7877_REG_SEQ1 13 68 #define AD7877_REG_DAC 14 69 #define AD7877_REG_NONE1 15 70 #define AD7877_REG_EXTWRITE 15 71 #define AD7877_REG_XPLUS 16 72 #define AD7877_REG_YPLUS 17 73 #define AD7877_REG_Z2 18 74 #define AD7877_REG_aux1 19 75 #define AD7877_REG_aux2 20 76 #define AD7877_REG_aux3 21 77 #define AD7877_REG_bat1 22 78 #define AD7877_REG_bat2 23 79 #define AD7877_REG_temp1 24 80 #define AD7877_REG_temp2 25 81 #define AD7877_REG_Z1 26 82 #define AD7877_REG_GPIOCTRL1 27 83 #define AD7877_REG_GPIOCTRL2 28 84 #define AD7877_REG_GPIODATA 29 85 #define AD7877_REG_NONE2 30 86 #define AD7877_REG_NONE3 31 87 88 #define AD7877_SEQ_YPLUS_BIT (1<<11) 89 #define AD7877_SEQ_XPLUS_BIT (1<<10) 90 #define AD7877_SEQ_Z2_BIT (1<<9) 91 #define AD7877_SEQ_AUX1_BIT (1<<8) 92 #define AD7877_SEQ_AUX2_BIT (1<<7) 93 #define AD7877_SEQ_AUX3_BIT (1<<6) 94 #define AD7877_SEQ_BAT1_BIT (1<<5) 95 #define AD7877_SEQ_BAT2_BIT (1<<4) 96 #define AD7877_SEQ_TEMP1_BIT (1<<3) 97 #define AD7877_SEQ_TEMP2_BIT (1<<2) 98 #define AD7877_SEQ_Z1_BIT (1<<1) 99 100 enum { 101 AD7877_SEQ_YPOS = 0, 102 AD7877_SEQ_XPOS = 1, 103 AD7877_SEQ_Z2 = 2, 104 AD7877_SEQ_AUX1 = 3, 105 AD7877_SEQ_AUX2 = 4, 106 AD7877_SEQ_AUX3 = 5, 107 AD7877_SEQ_BAT1 = 6, 108 AD7877_SEQ_BAT2 = 7, 109 AD7877_SEQ_TEMP1 = 8, 110 AD7877_SEQ_TEMP2 = 9, 111 AD7877_SEQ_Z1 = 10, 112 AD7877_NR_SENSE = 11, 113 }; 114 115 /* DAC Register Default RANGE 0 to Vcc, Volatge Mode, DAC On */ 116 #define AD7877_DAC_CONF 0x1 117 118 /* If gpio3 is set AUX3/GPIO3 acts as GPIO Output */ 119 #define AD7877_EXTW_GPIO_3_CONF 0x1C4 120 #define AD7877_EXTW_GPIO_DATA 0x200 121 122 /* Control REG 2 */ 123 #define AD7877_TMR(x) ((x & 0x3) << 0) 124 #define AD7877_REF(x) ((x & 0x1) << 2) 125 #define AD7877_POL(x) ((x & 0x1) << 3) 126 #define AD7877_FCD(x) ((x & 0x3) << 4) 127 #define AD7877_PM(x) ((x & 0x3) << 6) 128 #define AD7877_ACQ(x) ((x & 0x3) << 8) 129 #define AD7877_AVG(x) ((x & 0x3) << 10) 130 131 /* Control REG 1 */ 132 #define AD7877_SER (1 << 11) /* non-differential */ 133 #define AD7877_DFR (0 << 11) /* differential */ 134 135 #define AD7877_MODE_NOC (0) /* Do not convert */ 136 #define AD7877_MODE_SCC (1) /* Single channel conversion */ 137 #define AD7877_MODE_SEQ0 (2) /* Sequence 0 in Slave Mode */ 138 #define AD7877_MODE_SEQ1 (3) /* Sequence 1 in Master Mode */ 139 140 #define AD7877_CHANADD(x) ((x&0xF)<<7) 141 #define AD7877_READADD(x) ((x)<<2) 142 #define AD7877_WRITEADD(x) ((x)<<12) 143 144 #define AD7877_READ_CHAN(x) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_SER | \ 145 AD7877_MODE_SCC | AD7877_CHANADD(AD7877_REG_ ## x) | \ 146 AD7877_READADD(AD7877_REG_ ## x)) 147 148 #define AD7877_MM_SEQUENCE (AD7877_SEQ_YPLUS_BIT | AD7877_SEQ_XPLUS_BIT | \ 149 AD7877_SEQ_Z2_BIT | AD7877_SEQ_Z1_BIT) 150 151 /* 152 * Non-touchscreen sensors only use single-ended conversions. 153 */ 154 155 struct ser_req { 156 u16 reset; 157 u16 ref_on; 158 u16 command; 159 struct spi_message msg; 160 struct spi_transfer xfer[6]; 161 162 /* 163 * DMA (thus cache coherency maintenance) requires the 164 * transfer buffers to live in their own cache lines. 165 */ 166 u16 sample ____cacheline_aligned; 167 }; 168 169 struct ad7877 { 170 struct input_dev *input; 171 char phys[32]; 172 173 struct spi_device *spi; 174 u16 model; 175 u16 vref_delay_usecs; 176 u16 x_plate_ohms; 177 u16 pressure_max; 178 179 u16 cmd_crtl1; 180 u16 cmd_crtl2; 181 u16 cmd_dummy; 182 u16 dac; 183 184 u8 stopacq_polarity; 185 u8 first_conversion_delay; 186 u8 acquisition_time; 187 u8 averaging; 188 u8 pen_down_acc_interval; 189 190 struct spi_transfer xfer[AD7877_NR_SENSE + 2]; 191 struct spi_message msg; 192 193 struct mutex mutex; 194 unsigned disabled:1; /* P: mutex */ 195 unsigned gpio3:1; /* P: mutex */ 196 unsigned gpio4:1; /* P: mutex */ 197 198 spinlock_t lock; 199 struct timer_list timer; /* P: lock */ 200 unsigned pending:1; /* P: lock */ 201 202 /* 203 * DMA (thus cache coherency maintenance) requires the 204 * transfer buffers to live in their own cache lines. 205 */ 206 u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned; 207 }; 208 209 static int gpio3; 210 module_param(gpio3, int, 0); 211 MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3"); 212 213 /* 214 * ad7877_read/write are only used for initial setup and for sysfs controls. 215 * The main traffic is done using spi_async() in the interrupt handler. 216 */ 217 218 static int ad7877_read(struct spi_device *spi, u16 reg) 219 { 220 struct ser_req *req; 221 int status, ret; 222 223 req = kzalloc(sizeof *req, GFP_KERNEL); 224 if (!req) 225 return -ENOMEM; 226 227 spi_message_init(&req->msg); 228 229 req->command = (u16) (AD7877_WRITEADD(AD7877_REG_CTRL1) | 230 AD7877_READADD(reg)); 231 req->xfer[0].tx_buf = &req->command; 232 req->xfer[0].len = 2; 233 234 req->xfer[1].rx_buf = &req->sample; 235 req->xfer[1].len = 2; 236 237 spi_message_add_tail(&req->xfer[0], &req->msg); 238 spi_message_add_tail(&req->xfer[1], &req->msg); 239 240 status = spi_sync(spi, &req->msg); 241 ret = status ? : req->sample; 242 243 kfree(req); 244 245 return ret; 246 } 247 248 static int ad7877_write(struct spi_device *spi, u16 reg, u16 val) 249 { 250 struct ser_req *req; 251 int status; 252 253 req = kzalloc(sizeof *req, GFP_KERNEL); 254 if (!req) 255 return -ENOMEM; 256 257 spi_message_init(&req->msg); 258 259 req->command = (u16) (AD7877_WRITEADD(reg) | (val & MAX_12BIT)); 260 req->xfer[0].tx_buf = &req->command; 261 req->xfer[0].len = 2; 262 263 spi_message_add_tail(&req->xfer[0], &req->msg); 264 265 status = spi_sync(spi, &req->msg); 266 267 kfree(req); 268 269 return status; 270 } 271 272 static int ad7877_read_adc(struct spi_device *spi, unsigned command) 273 { 274 struct ad7877 *ts = dev_get_drvdata(&spi->dev); 275 struct ser_req *req; 276 int status; 277 int sample; 278 int i; 279 280 req = kzalloc(sizeof *req, GFP_KERNEL); 281 if (!req) 282 return -ENOMEM; 283 284 spi_message_init(&req->msg); 285 286 /* activate reference, so it has time to settle; */ 287 req->ref_on = AD7877_WRITEADD(AD7877_REG_CTRL2) | 288 AD7877_POL(ts->stopacq_polarity) | 289 AD7877_AVG(0) | AD7877_PM(2) | AD7877_TMR(0) | 290 AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(0); 291 292 req->reset = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_MODE_NOC; 293 294 req->command = (u16) command; 295 296 req->xfer[0].tx_buf = &req->reset; 297 req->xfer[0].len = 2; 298 299 req->xfer[1].tx_buf = &req->ref_on; 300 req->xfer[1].len = 2; 301 req->xfer[1].delay_usecs = ts->vref_delay_usecs; 302 303 req->xfer[2].tx_buf = &req->command; 304 req->xfer[2].len = 2; 305 req->xfer[2].delay_usecs = ts->vref_delay_usecs; 306 307 req->xfer[3].rx_buf = &req->sample; 308 req->xfer[3].len = 2; 309 310 req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/ 311 req->xfer[4].len = 2; 312 313 req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/ 314 req->xfer[5].len = 2; 315 316 /* group all the transfers together, so we can't interfere with 317 * reading touchscreen state; disable penirq while sampling 318 */ 319 for (i = 0; i < 6; i++) 320 spi_message_add_tail(&req->xfer[i], &req->msg); 321 322 status = spi_sync(spi, &req->msg); 323 sample = req->sample; 324 325 kfree(req); 326 327 return status ? : sample; 328 } 329 330 static void ad7877_rx(struct ad7877 *ts) 331 { 332 struct input_dev *input_dev = ts->input; 333 unsigned Rt; 334 u16 x, y, z1, z2; 335 336 x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT; 337 y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT; 338 z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT; 339 z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT; 340 341 /* 342 * The samples processed here are already preprocessed by the AD7877. 343 * The preprocessing function consists of an averaging filter. 344 * The combination of 'first conversion delay' and averaging provides a robust solution, 345 * discarding the spurious noise in the signal and keeping only the data of interest. 346 * The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h) 347 * Other user-programmable conversion controls include variable acquisition time, 348 * and first conversion delay. Up to 16 averages can be taken per conversion. 349 */ 350 351 if (likely(x && z1)) { 352 /* compute touch pressure resistance using equation #1 */ 353 Rt = (z2 - z1) * x * ts->x_plate_ohms; 354 Rt /= z1; 355 Rt = (Rt + 2047) >> 12; 356 357 input_report_abs(input_dev, ABS_X, x); 358 input_report_abs(input_dev, ABS_Y, y); 359 input_report_abs(input_dev, ABS_PRESSURE, Rt); 360 input_sync(input_dev); 361 } 362 } 363 364 static inline void ad7877_ts_event_release(struct ad7877 *ts) 365 { 366 struct input_dev *input_dev = ts->input; 367 368 input_report_abs(input_dev, ABS_PRESSURE, 0); 369 input_sync(input_dev); 370 } 371 372 static void ad7877_timer(unsigned long handle) 373 { 374 struct ad7877 *ts = (void *)handle; 375 376 ad7877_ts_event_release(ts); 377 } 378 379 static irqreturn_t ad7877_irq(int irq, void *handle) 380 { 381 struct ad7877 *ts = handle; 382 unsigned long flags; 383 int status; 384 385 /* 386 * The repeated conversion sequencer controlled by TMR kicked off 387 * too fast. We ignore the last and process the sample sequence 388 * currently in the queue. It can't be older than 9.4ms, and we 389 * need to avoid that ts->msg doesn't get issued twice while in work. 390 */ 391 392 spin_lock_irqsave(&ts->lock, flags); 393 if (!ts->pending) { 394 ts->pending = 1; 395 396 status = spi_async(ts->spi, &ts->msg); 397 if (status) 398 dev_err(&ts->spi->dev, "spi_sync --> %d\n", status); 399 } 400 spin_unlock_irqrestore(&ts->lock, flags); 401 402 return IRQ_HANDLED; 403 } 404 405 static void ad7877_callback(void *_ts) 406 { 407 struct ad7877 *ts = _ts; 408 409 spin_lock_irq(&ts->lock); 410 411 ad7877_rx(ts); 412 ts->pending = 0; 413 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT); 414 415 spin_unlock_irq(&ts->lock); 416 } 417 418 static void ad7877_disable(struct ad7877 *ts) 419 { 420 mutex_lock(&ts->mutex); 421 422 if (!ts->disabled) { 423 ts->disabled = 1; 424 disable_irq(ts->spi->irq); 425 426 /* Wait for spi_async callback */ 427 while (ts->pending) 428 msleep(1); 429 430 if (del_timer_sync(&ts->timer)) 431 ad7877_ts_event_release(ts); 432 } 433 434 /* we know the chip's in lowpower mode since we always 435 * leave it that way after every request 436 */ 437 438 mutex_unlock(&ts->mutex); 439 } 440 441 static void ad7877_enable(struct ad7877 *ts) 442 { 443 mutex_lock(&ts->mutex); 444 445 if (ts->disabled) { 446 ts->disabled = 0; 447 enable_irq(ts->spi->irq); 448 } 449 450 mutex_unlock(&ts->mutex); 451 } 452 453 #define SHOW(name) static ssize_t \ 454 name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ 455 { \ 456 struct ad7877 *ts = dev_get_drvdata(dev); \ 457 ssize_t v = ad7877_read_adc(ts->spi, \ 458 AD7877_READ_CHAN(name)); \ 459 if (v < 0) \ 460 return v; \ 461 return sprintf(buf, "%u\n", (unsigned) v); \ 462 } \ 463 static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); 464 465 SHOW(aux1) 466 SHOW(aux2) 467 SHOW(aux3) 468 SHOW(bat1) 469 SHOW(bat2) 470 SHOW(temp1) 471 SHOW(temp2) 472 473 static ssize_t ad7877_disable_show(struct device *dev, 474 struct device_attribute *attr, char *buf) 475 { 476 struct ad7877 *ts = dev_get_drvdata(dev); 477 478 return sprintf(buf, "%u\n", ts->disabled); 479 } 480 481 static ssize_t ad7877_disable_store(struct device *dev, 482 struct device_attribute *attr, 483 const char *buf, size_t count) 484 { 485 struct ad7877 *ts = dev_get_drvdata(dev); 486 unsigned long val; 487 int error; 488 489 error = strict_strtoul(buf, 10, &val); 490 if (error) 491 return error; 492 493 if (val) 494 ad7877_disable(ts); 495 else 496 ad7877_enable(ts); 497 498 return count; 499 } 500 501 static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store); 502 503 static ssize_t ad7877_dac_show(struct device *dev, 504 struct device_attribute *attr, char *buf) 505 { 506 struct ad7877 *ts = dev_get_drvdata(dev); 507 508 return sprintf(buf, "%u\n", ts->dac); 509 } 510 511 static ssize_t ad7877_dac_store(struct device *dev, 512 struct device_attribute *attr, 513 const char *buf, size_t count) 514 { 515 struct ad7877 *ts = dev_get_drvdata(dev); 516 unsigned long val; 517 int error; 518 519 error = strict_strtoul(buf, 10, &val); 520 if (error) 521 return error; 522 523 mutex_lock(&ts->mutex); 524 ts->dac = val & 0xFF; 525 ad7877_write(ts->spi, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF); 526 mutex_unlock(&ts->mutex); 527 528 return count; 529 } 530 531 static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store); 532 533 static ssize_t ad7877_gpio3_show(struct device *dev, 534 struct device_attribute *attr, char *buf) 535 { 536 struct ad7877 *ts = dev_get_drvdata(dev); 537 538 return sprintf(buf, "%u\n", ts->gpio3); 539 } 540 541 static ssize_t ad7877_gpio3_store(struct device *dev, 542 struct device_attribute *attr, 543 const char *buf, size_t count) 544 { 545 struct ad7877 *ts = dev_get_drvdata(dev); 546 unsigned long val; 547 int error; 548 549 error = strict_strtoul(buf, 10, &val); 550 if (error) 551 return error; 552 553 mutex_lock(&ts->mutex); 554 ts->gpio3 = !!val; 555 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | 556 (ts->gpio4 << 4) | (ts->gpio3 << 5)); 557 mutex_unlock(&ts->mutex); 558 559 return count; 560 } 561 562 static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store); 563 564 static ssize_t ad7877_gpio4_show(struct device *dev, 565 struct device_attribute *attr, char *buf) 566 { 567 struct ad7877 *ts = dev_get_drvdata(dev); 568 569 return sprintf(buf, "%u\n", ts->gpio4); 570 } 571 572 static ssize_t ad7877_gpio4_store(struct device *dev, 573 struct device_attribute *attr, 574 const char *buf, size_t count) 575 { 576 struct ad7877 *ts = dev_get_drvdata(dev); 577 unsigned long val; 578 int error; 579 580 error = strict_strtoul(buf, 10, &val); 581 if (error) 582 return error; 583 584 mutex_lock(&ts->mutex); 585 ts->gpio4 = !!val; 586 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | 587 (ts->gpio4 << 4) | (ts->gpio3 << 5)); 588 mutex_unlock(&ts->mutex); 589 590 return count; 591 } 592 593 static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store); 594 595 static struct attribute *ad7877_attributes[] = { 596 &dev_attr_temp1.attr, 597 &dev_attr_temp2.attr, 598 &dev_attr_aux1.attr, 599 &dev_attr_aux2.attr, 600 &dev_attr_bat1.attr, 601 &dev_attr_bat2.attr, 602 &dev_attr_disable.attr, 603 &dev_attr_dac.attr, 604 &dev_attr_gpio4.attr, 605 NULL 606 }; 607 608 static const struct attribute_group ad7877_attr_group = { 609 .attrs = ad7877_attributes, 610 }; 611 612 static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts) 613 { 614 struct spi_message *m; 615 int i; 616 617 ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) | 618 AD7877_POL(ts->stopacq_polarity) | 619 AD7877_AVG(ts->averaging) | AD7877_PM(1) | 620 AD7877_TMR(ts->pen_down_acc_interval) | 621 AD7877_ACQ(ts->acquisition_time) | 622 AD7877_FCD(ts->first_conversion_delay); 623 624 ad7877_write(spi, AD7877_REG_CTRL2, ts->cmd_crtl2); 625 626 ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) | 627 AD7877_READADD(AD7877_REG_XPLUS-1) | 628 AD7877_MODE_SEQ1 | AD7877_DFR; 629 630 ad7877_write(spi, AD7877_REG_CTRL1, ts->cmd_crtl1); 631 632 ts->cmd_dummy = 0; 633 634 m = &ts->msg; 635 636 spi_message_init(m); 637 638 m->complete = ad7877_callback; 639 m->context = ts; 640 641 ts->xfer[0].tx_buf = &ts->cmd_crtl1; 642 ts->xfer[0].len = 2; 643 644 spi_message_add_tail(&ts->xfer[0], m); 645 646 ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */ 647 ts->xfer[1].len = 2; 648 649 spi_message_add_tail(&ts->xfer[1], m); 650 651 for (i = 0; i < 11; i++) { 652 ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i]; 653 ts->xfer[i + 2].len = 2; 654 spi_message_add_tail(&ts->xfer[i + 2], m); 655 } 656 } 657 658 static int __devinit ad7877_probe(struct spi_device *spi) 659 { 660 struct ad7877 *ts; 661 struct input_dev *input_dev; 662 struct ad7877_platform_data *pdata = spi->dev.platform_data; 663 int err; 664 u16 verify; 665 666 if (!spi->irq) { 667 dev_dbg(&spi->dev, "no IRQ?\n"); 668 return -ENODEV; 669 } 670 671 if (!pdata) { 672 dev_dbg(&spi->dev, "no platform data?\n"); 673 return -ENODEV; 674 } 675 676 /* don't exceed max specified SPI CLK frequency */ 677 if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { 678 dev_dbg(&spi->dev, "SPI CLK %d Hz?\n",spi->max_speed_hz); 679 return -EINVAL; 680 } 681 682 spi->bits_per_word = 16; 683 err = spi_setup(spi); 684 if (err) { 685 dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n"); 686 return err; 687 } 688 689 ts = kzalloc(sizeof(struct ad7877), GFP_KERNEL); 690 input_dev = input_allocate_device(); 691 if (!ts || !input_dev) { 692 err = -ENOMEM; 693 goto err_free_mem; 694 } 695 696 dev_set_drvdata(&spi->dev, ts); 697 ts->spi = spi; 698 ts->input = input_dev; 699 700 setup_timer(&ts->timer, ad7877_timer, (unsigned long) ts); 701 mutex_init(&ts->mutex); 702 spin_lock_init(&ts->lock); 703 704 ts->model = pdata->model ? : 7877; 705 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; 706 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; 707 ts->pressure_max = pdata->pressure_max ? : ~0; 708 709 ts->stopacq_polarity = pdata->stopacq_polarity; 710 ts->first_conversion_delay = pdata->first_conversion_delay; 711 ts->acquisition_time = pdata->acquisition_time; 712 ts->averaging = pdata->averaging; 713 ts->pen_down_acc_interval = pdata->pen_down_acc_interval; 714 715 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); 716 717 input_dev->name = "AD7877 Touchscreen"; 718 input_dev->phys = ts->phys; 719 input_dev->dev.parent = &spi->dev; 720 721 __set_bit(EV_ABS, input_dev->evbit); 722 __set_bit(ABS_X, input_dev->absbit); 723 __set_bit(ABS_Y, input_dev->absbit); 724 __set_bit(ABS_PRESSURE, input_dev->absbit); 725 726 input_set_abs_params(input_dev, ABS_X, 727 pdata->x_min ? : 0, 728 pdata->x_max ? : MAX_12BIT, 729 0, 0); 730 input_set_abs_params(input_dev, ABS_Y, 731 pdata->y_min ? : 0, 732 pdata->y_max ? : MAX_12BIT, 733 0, 0); 734 input_set_abs_params(input_dev, ABS_PRESSURE, 735 pdata->pressure_min, pdata->pressure_max, 0, 0); 736 737 ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE); 738 739 verify = ad7877_read(spi, AD7877_REG_SEQ1); 740 741 if (verify != AD7877_MM_SEQUENCE){ 742 dev_err(&spi->dev, "%s: Failed to probe %s\n", 743 dev_name(&spi->dev), input_dev->name); 744 err = -ENODEV; 745 goto err_free_mem; 746 } 747 748 if (gpio3) 749 ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF); 750 751 ad7877_setup_ts_def_msg(spi, ts); 752 753 /* Request AD7877 /DAV GPIO interrupt */ 754 755 err = request_irq(spi->irq, ad7877_irq, IRQF_TRIGGER_FALLING, 756 spi->dev.driver->name, ts); 757 if (err) { 758 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); 759 goto err_free_mem; 760 } 761 762 err = sysfs_create_group(&spi->dev.kobj, &ad7877_attr_group); 763 if (err) 764 goto err_free_irq; 765 766 err = device_create_file(&spi->dev, 767 gpio3 ? &dev_attr_gpio3 : &dev_attr_aux3); 768 if (err) 769 goto err_remove_attr_group; 770 771 err = input_register_device(input_dev); 772 if (err) 773 goto err_remove_attr; 774 775 return 0; 776 777 err_remove_attr: 778 device_remove_file(&spi->dev, 779 gpio3 ? &dev_attr_gpio3 : &dev_attr_aux3); 780 err_remove_attr_group: 781 sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group); 782 err_free_irq: 783 free_irq(spi->irq, ts); 784 err_free_mem: 785 input_free_device(input_dev); 786 kfree(ts); 787 dev_set_drvdata(&spi->dev, NULL); 788 return err; 789 } 790 791 static int __devexit ad7877_remove(struct spi_device *spi) 792 { 793 struct ad7877 *ts = dev_get_drvdata(&spi->dev); 794 795 sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group); 796 device_remove_file(&spi->dev, 797 gpio3 ? &dev_attr_gpio3 : &dev_attr_aux3); 798 799 ad7877_disable(ts); 800 free_irq(ts->spi->irq, ts); 801 802 input_unregister_device(ts->input); 803 kfree(ts); 804 805 dev_dbg(&spi->dev, "unregistered touchscreen\n"); 806 dev_set_drvdata(&spi->dev, NULL); 807 808 return 0; 809 } 810 811 #ifdef CONFIG_PM 812 static int ad7877_suspend(struct spi_device *spi, pm_message_t message) 813 { 814 struct ad7877 *ts = dev_get_drvdata(&spi->dev); 815 816 ad7877_disable(ts); 817 818 return 0; 819 } 820 821 static int ad7877_resume(struct spi_device *spi) 822 { 823 struct ad7877 *ts = dev_get_drvdata(&spi->dev); 824 825 ad7877_enable(ts); 826 827 return 0; 828 } 829 #else 830 #define ad7877_suspend NULL 831 #define ad7877_resume NULL 832 #endif 833 834 static struct spi_driver ad7877_driver = { 835 .driver = { 836 .name = "ad7877", 837 .bus = &spi_bus_type, 838 .owner = THIS_MODULE, 839 }, 840 .probe = ad7877_probe, 841 .remove = __devexit_p(ad7877_remove), 842 .suspend = ad7877_suspend, 843 .resume = ad7877_resume, 844 }; 845 846 static int __init ad7877_init(void) 847 { 848 return spi_register_driver(&ad7877_driver); 849 } 850 module_init(ad7877_init); 851 852 static void __exit ad7877_exit(void) 853 { 854 spi_unregister_driver(&ad7877_driver); 855 } 856 module_exit(ad7877_exit); 857 858 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 859 MODULE_DESCRIPTION("AD7877 touchscreen Driver"); 860 MODULE_LICENSE("GPL"); 861 MODULE_ALIAS("spi:ad7877"); 862