1 /* 2 * Copyright (C) 2008-2009 Michael Hennerich, Analog Devices Inc. 3 * 4 * Description: AD7879/AD7889 based touchscreen, and GPIO driver 5 * (I2C/SPI Interface) 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 * - ad7877.c 37 * Copyright (C) 2006-2008 Analog Devices Inc. 38 */ 39 40 #include <linux/device.h> 41 #include <linux/init.h> 42 #include <linux/delay.h> 43 #include <linux/input.h> 44 #include <linux/interrupt.h> 45 #include <linux/irq.h> 46 #include <linux/slab.h> 47 #include <linux/workqueue.h> 48 #include <linux/spi/spi.h> 49 #include <linux/i2c.h> 50 51 #include <linux/spi/ad7879.h> 52 53 #define AD7879_REG_ZEROS 0 54 #define AD7879_REG_CTRL1 1 55 #define AD7879_REG_CTRL2 2 56 #define AD7879_REG_CTRL3 3 57 #define AD7879_REG_AUX1HIGH 4 58 #define AD7879_REG_AUX1LOW 5 59 #define AD7879_REG_TEMP1HIGH 6 60 #define AD7879_REG_TEMP1LOW 7 61 #define AD7879_REG_XPLUS 8 62 #define AD7879_REG_YPLUS 9 63 #define AD7879_REG_Z1 10 64 #define AD7879_REG_Z2 11 65 #define AD7879_REG_AUXVBAT 12 66 #define AD7879_REG_TEMP 13 67 #define AD7879_REG_REVID 14 68 69 /* Control REG 1 */ 70 #define AD7879_TMR(x) ((x & 0xFF) << 0) 71 #define AD7879_ACQ(x) ((x & 0x3) << 8) 72 #define AD7879_MODE_NOC (0 << 10) /* Do not convert */ 73 #define AD7879_MODE_SCC (1 << 10) /* Single channel conversion */ 74 #define AD7879_MODE_SEQ0 (2 << 10) /* Sequence 0 in Slave Mode */ 75 #define AD7879_MODE_SEQ1 (3 << 10) /* Sequence 1 in Master Mode */ 76 #define AD7879_MODE_INT (1 << 15) /* PENIRQ disabled INT enabled */ 77 78 /* Control REG 2 */ 79 #define AD7879_FCD(x) ((x & 0x3) << 0) 80 #define AD7879_RESET (1 << 4) 81 #define AD7879_MFS(x) ((x & 0x3) << 5) 82 #define AD7879_AVG(x) ((x & 0x3) << 7) 83 #define AD7879_SER (1 << 9) /* non-differential */ 84 #define AD7879_DFR (0 << 9) /* differential */ 85 #define AD7879_GPIOPOL (1 << 10) 86 #define AD7879_GPIODIR (1 << 11) 87 #define AD7879_GPIO_DATA (1 << 12) 88 #define AD7879_GPIO_EN (1 << 13) 89 #define AD7879_PM(x) ((x & 0x3) << 14) 90 #define AD7879_PM_SHUTDOWN (0) 91 #define AD7879_PM_DYN (1) 92 #define AD7879_PM_FULLON (2) 93 94 /* Control REG 3 */ 95 #define AD7879_TEMPMASK_BIT (1<<15) 96 #define AD7879_AUXVBATMASK_BIT (1<<14) 97 #define AD7879_INTMODE_BIT (1<<13) 98 #define AD7879_GPIOALERTMASK_BIT (1<<12) 99 #define AD7879_AUXLOW_BIT (1<<11) 100 #define AD7879_AUXHIGH_BIT (1<<10) 101 #define AD7879_TEMPLOW_BIT (1<<9) 102 #define AD7879_TEMPHIGH_BIT (1<<8) 103 #define AD7879_YPLUS_BIT (1<<7) 104 #define AD7879_XPLUS_BIT (1<<6) 105 #define AD7879_Z1_BIT (1<<5) 106 #define AD7879_Z2_BIT (1<<4) 107 #define AD7879_AUX_BIT (1<<3) 108 #define AD7879_VBAT_BIT (1<<2) 109 #define AD7879_TEMP_BIT (1<<1) 110 111 enum { 112 AD7879_SEQ_XPOS = 0, 113 AD7879_SEQ_YPOS = 1, 114 AD7879_SEQ_Z1 = 2, 115 AD7879_SEQ_Z2 = 3, 116 AD7879_NR_SENSE = 4, 117 }; 118 119 #define MAX_12BIT ((1<<12)-1) 120 #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50) 121 122 #if defined(CONFIG_TOUCHSCREEN_AD7879_SPI) || defined(CONFIG_TOUCHSCREEN_AD7879_SPI_MODULE) 123 #define AD7879_DEVID 0x7A 124 typedef struct spi_device bus_device; 125 #elif defined(CONFIG_TOUCHSCREEN_AD7879_I2C) || defined(CONFIG_TOUCHSCREEN_AD7879_I2C_MODULE) 126 #define AD7879_DEVID 0x79 127 typedef struct i2c_client bus_device; 128 #endif 129 130 struct ad7879 { 131 bus_device *bus; 132 struct input_dev *input; 133 struct work_struct work; 134 struct timer_list timer; 135 136 struct mutex mutex; 137 unsigned disabled:1; /* P: mutex */ 138 139 #if defined(CONFIG_TOUCHSCREEN_AD7879_SPI) || defined(CONFIG_TOUCHSCREEN_AD7879_SPI_MODULE) 140 struct spi_message msg; 141 struct spi_transfer xfer[AD7879_NR_SENSE + 1]; 142 u16 cmd; 143 #endif 144 u16 conversion_data[AD7879_NR_SENSE]; 145 char phys[32]; 146 u8 first_conversion_delay; 147 u8 acquisition_time; 148 u8 averaging; 149 u8 pen_down_acc_interval; 150 u8 median; 151 u16 x_plate_ohms; 152 u16 pressure_max; 153 u16 gpio_init; 154 u16 cmd_crtl1; 155 u16 cmd_crtl2; 156 u16 cmd_crtl3; 157 unsigned gpio:1; 158 }; 159 160 static int ad7879_read(bus_device *, u8); 161 static int ad7879_write(bus_device *, u8, u16); 162 static void ad7879_collect(struct ad7879 *); 163 164 static void ad7879_report(struct ad7879 *ts) 165 { 166 struct input_dev *input_dev = ts->input; 167 unsigned Rt; 168 u16 x, y, z1, z2; 169 170 x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT; 171 y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT; 172 z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT; 173 z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT; 174 175 /* 176 * The samples processed here are already preprocessed by the AD7879. 177 * The preprocessing function consists of a median and an averaging filter. 178 * The combination of these two techniques provides a robust solution, 179 * discarding the spurious noise in the signal and keeping only the data of interest. 180 * The size of both filters is programmable. (dev.platform_data, see linux/spi/ad7879.h) 181 * Other user-programmable conversion controls include variable acquisition time, 182 * and first conversion delay. Up to 16 averages can be taken per conversion. 183 */ 184 185 if (likely(x && z1)) { 186 /* compute touch pressure resistance using equation #1 */ 187 Rt = (z2 - z1) * x * ts->x_plate_ohms; 188 Rt /= z1; 189 Rt = (Rt + 2047) >> 12; 190 191 input_report_abs(input_dev, ABS_X, x); 192 input_report_abs(input_dev, ABS_Y, y); 193 input_report_abs(input_dev, ABS_PRESSURE, Rt); 194 input_sync(input_dev); 195 } 196 } 197 198 static void ad7879_work(struct work_struct *work) 199 { 200 struct ad7879 *ts = container_of(work, struct ad7879, work); 201 202 /* use keventd context to read the result registers */ 203 ad7879_collect(ts); 204 ad7879_report(ts); 205 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT); 206 } 207 208 static void ad7879_ts_event_release(struct ad7879 *ts) 209 { 210 struct input_dev *input_dev = ts->input; 211 212 input_report_abs(input_dev, ABS_PRESSURE, 0); 213 input_sync(input_dev); 214 } 215 216 static void ad7879_timer(unsigned long handle) 217 { 218 struct ad7879 *ts = (void *)handle; 219 220 ad7879_ts_event_release(ts); 221 } 222 223 static irqreturn_t ad7879_irq(int irq, void *handle) 224 { 225 struct ad7879 *ts = handle; 226 227 /* The repeated conversion sequencer controlled by TMR kicked off too fast. 228 * We ignore the last and process the sample sequence currently in the queue. 229 * It can't be older than 9.4ms 230 */ 231 232 if (!work_pending(&ts->work)) 233 schedule_work(&ts->work); 234 235 return IRQ_HANDLED; 236 } 237 238 static void ad7879_setup(struct ad7879 *ts) 239 { 240 ts->cmd_crtl3 = AD7879_YPLUS_BIT | 241 AD7879_XPLUS_BIT | 242 AD7879_Z2_BIT | 243 AD7879_Z1_BIT | 244 AD7879_TEMPMASK_BIT | 245 AD7879_AUXVBATMASK_BIT | 246 AD7879_GPIOALERTMASK_BIT; 247 248 ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) | AD7879_DFR | 249 AD7879_AVG(ts->averaging) | 250 AD7879_MFS(ts->median) | 251 AD7879_FCD(ts->first_conversion_delay) | 252 ts->gpio_init; 253 254 ts->cmd_crtl1 = AD7879_MODE_INT | AD7879_MODE_SEQ1 | 255 AD7879_ACQ(ts->acquisition_time) | 256 AD7879_TMR(ts->pen_down_acc_interval); 257 258 ad7879_write(ts->bus, AD7879_REG_CTRL2, ts->cmd_crtl2); 259 ad7879_write(ts->bus, AD7879_REG_CTRL3, ts->cmd_crtl3); 260 ad7879_write(ts->bus, AD7879_REG_CTRL1, ts->cmd_crtl1); 261 } 262 263 static void ad7879_disable(struct ad7879 *ts) 264 { 265 mutex_lock(&ts->mutex); 266 267 if (!ts->disabled) { 268 269 ts->disabled = 1; 270 disable_irq(ts->bus->irq); 271 272 cancel_work_sync(&ts->work); 273 274 if (del_timer_sync(&ts->timer)) 275 ad7879_ts_event_release(ts); 276 277 ad7879_write(ts->bus, AD7879_REG_CTRL2, 278 AD7879_PM(AD7879_PM_SHUTDOWN)); 279 } 280 281 mutex_unlock(&ts->mutex); 282 } 283 284 static void ad7879_enable(struct ad7879 *ts) 285 { 286 mutex_lock(&ts->mutex); 287 288 if (ts->disabled) { 289 ad7879_setup(ts); 290 ts->disabled = 0; 291 enable_irq(ts->bus->irq); 292 } 293 294 mutex_unlock(&ts->mutex); 295 } 296 297 static ssize_t ad7879_disable_show(struct device *dev, 298 struct device_attribute *attr, char *buf) 299 { 300 struct ad7879 *ts = dev_get_drvdata(dev); 301 302 return sprintf(buf, "%u\n", ts->disabled); 303 } 304 305 static ssize_t ad7879_disable_store(struct device *dev, 306 struct device_attribute *attr, 307 const char *buf, size_t count) 308 { 309 struct ad7879 *ts = dev_get_drvdata(dev); 310 unsigned long val; 311 int error; 312 313 error = strict_strtoul(buf, 10, &val); 314 if (error) 315 return error; 316 317 if (val) 318 ad7879_disable(ts); 319 else 320 ad7879_enable(ts); 321 322 return count; 323 } 324 325 static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store); 326 327 static ssize_t ad7879_gpio_show(struct device *dev, 328 struct device_attribute *attr, char *buf) 329 { 330 struct ad7879 *ts = dev_get_drvdata(dev); 331 332 return sprintf(buf, "%u\n", ts->gpio); 333 } 334 335 static ssize_t ad7879_gpio_store(struct device *dev, 336 struct device_attribute *attr, 337 const char *buf, size_t count) 338 { 339 struct ad7879 *ts = dev_get_drvdata(dev); 340 unsigned long val; 341 int error; 342 343 error = strict_strtoul(buf, 10, &val); 344 if (error) 345 return error; 346 347 mutex_lock(&ts->mutex); 348 ts->gpio = !!val; 349 error = ad7879_write(ts->bus, AD7879_REG_CTRL2, 350 ts->gpio ? 351 ts->cmd_crtl2 & ~AD7879_GPIO_DATA : 352 ts->cmd_crtl2 | AD7879_GPIO_DATA); 353 mutex_unlock(&ts->mutex); 354 355 return error ? : count; 356 } 357 358 static DEVICE_ATTR(gpio, 0664, ad7879_gpio_show, ad7879_gpio_store); 359 360 static struct attribute *ad7879_attributes[] = { 361 &dev_attr_disable.attr, 362 &dev_attr_gpio.attr, 363 NULL 364 }; 365 366 static const struct attribute_group ad7879_attr_group = { 367 .attrs = ad7879_attributes, 368 }; 369 370 static int __devinit ad7879_construct(bus_device *bus, struct ad7879 *ts) 371 { 372 struct input_dev *input_dev; 373 struct ad7879_platform_data *pdata = bus->dev.platform_data; 374 int err; 375 u16 revid; 376 377 if (!bus->irq) { 378 dev_err(&bus->dev, "no IRQ?\n"); 379 return -ENODEV; 380 } 381 382 if (!pdata) { 383 dev_err(&bus->dev, "no platform data?\n"); 384 return -ENODEV; 385 } 386 387 input_dev = input_allocate_device(); 388 if (!input_dev) 389 return -ENOMEM; 390 391 ts->input = input_dev; 392 393 setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts); 394 INIT_WORK(&ts->work, ad7879_work); 395 mutex_init(&ts->mutex); 396 397 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; 398 ts->pressure_max = pdata->pressure_max ? : ~0; 399 400 ts->first_conversion_delay = pdata->first_conversion_delay; 401 ts->acquisition_time = pdata->acquisition_time; 402 ts->averaging = pdata->averaging; 403 ts->pen_down_acc_interval = pdata->pen_down_acc_interval; 404 ts->median = pdata->median; 405 406 if (pdata->gpio_output) 407 ts->gpio_init = AD7879_GPIO_EN | 408 (pdata->gpio_default ? 0 : AD7879_GPIO_DATA); 409 else 410 ts->gpio_init = AD7879_GPIO_EN | AD7879_GPIODIR; 411 412 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&bus->dev)); 413 414 input_dev->name = "AD7879 Touchscreen"; 415 input_dev->phys = ts->phys; 416 input_dev->dev.parent = &bus->dev; 417 418 __set_bit(EV_ABS, input_dev->evbit); 419 __set_bit(ABS_X, input_dev->absbit); 420 __set_bit(ABS_Y, input_dev->absbit); 421 __set_bit(ABS_PRESSURE, input_dev->absbit); 422 423 input_set_abs_params(input_dev, ABS_X, 424 pdata->x_min ? : 0, 425 pdata->x_max ? : MAX_12BIT, 426 0, 0); 427 input_set_abs_params(input_dev, ABS_Y, 428 pdata->y_min ? : 0, 429 pdata->y_max ? : MAX_12BIT, 430 0, 0); 431 input_set_abs_params(input_dev, ABS_PRESSURE, 432 pdata->pressure_min, pdata->pressure_max, 0, 0); 433 434 err = ad7879_write(bus, AD7879_REG_CTRL2, AD7879_RESET); 435 436 if (err < 0) { 437 dev_err(&bus->dev, "Failed to write %s\n", input_dev->name); 438 goto err_free_mem; 439 } 440 441 revid = ad7879_read(bus, AD7879_REG_REVID); 442 443 if ((revid & 0xFF) != AD7879_DEVID) { 444 dev_err(&bus->dev, "Failed to probe %s\n", input_dev->name); 445 err = -ENODEV; 446 goto err_free_mem; 447 } 448 449 ad7879_setup(ts); 450 451 err = request_irq(bus->irq, ad7879_irq, 452 IRQF_TRIGGER_FALLING, bus->dev.driver->name, ts); 453 454 if (err) { 455 dev_err(&bus->dev, "irq %d busy?\n", bus->irq); 456 goto err_free_mem; 457 } 458 459 err = sysfs_create_group(&bus->dev.kobj, &ad7879_attr_group); 460 if (err) 461 goto err_free_irq; 462 463 err = input_register_device(input_dev); 464 if (err) 465 goto err_remove_attr; 466 467 dev_info(&bus->dev, "Rev.%d touchscreen, irq %d\n", 468 revid >> 8, bus->irq); 469 470 return 0; 471 472 err_remove_attr: 473 sysfs_remove_group(&bus->dev.kobj, &ad7879_attr_group); 474 err_free_irq: 475 free_irq(bus->irq, ts); 476 err_free_mem: 477 input_free_device(input_dev); 478 479 return err; 480 } 481 482 static int __devexit ad7879_destroy(bus_device *bus, struct ad7879 *ts) 483 { 484 ad7879_disable(ts); 485 sysfs_remove_group(&ts->bus->dev.kobj, &ad7879_attr_group); 486 free_irq(ts->bus->irq, ts); 487 input_unregister_device(ts->input); 488 dev_dbg(&bus->dev, "unregistered touchscreen\n"); 489 490 return 0; 491 } 492 493 #ifdef CONFIG_PM 494 static int ad7879_suspend(bus_device *bus, pm_message_t message) 495 { 496 struct ad7879 *ts = dev_get_drvdata(&bus->dev); 497 498 ad7879_disable(ts); 499 500 return 0; 501 } 502 503 static int ad7879_resume(bus_device *bus) 504 { 505 struct ad7879 *ts = dev_get_drvdata(&bus->dev); 506 507 ad7879_enable(ts); 508 509 return 0; 510 } 511 #else 512 #define ad7879_suspend NULL 513 #define ad7879_resume NULL 514 #endif 515 516 #if defined(CONFIG_TOUCHSCREEN_AD7879_SPI) || defined(CONFIG_TOUCHSCREEN_AD7879_SPI_MODULE) 517 #define MAX_SPI_FREQ_HZ 5000000 518 #define AD7879_CMD_MAGIC 0xE000 519 #define AD7879_CMD_READ (1 << 10) 520 #define AD7879_WRITECMD(reg) (AD7879_CMD_MAGIC | (reg & 0xF)) 521 #define AD7879_READCMD(reg) (AD7879_CMD_MAGIC | AD7879_CMD_READ | (reg & 0xF)) 522 523 struct ser_req { 524 u16 command; 525 u16 data; 526 struct spi_message msg; 527 struct spi_transfer xfer[2]; 528 }; 529 530 /* 531 * ad7879_read/write are only used for initial setup and for sysfs controls. 532 * The main traffic is done in ad7879_collect(). 533 */ 534 535 static int ad7879_read(struct spi_device *spi, u8 reg) 536 { 537 struct ser_req *req; 538 int status, ret; 539 540 req = kzalloc(sizeof *req, GFP_KERNEL); 541 if (!req) 542 return -ENOMEM; 543 544 spi_message_init(&req->msg); 545 546 req->command = (u16) AD7879_READCMD(reg); 547 req->xfer[0].tx_buf = &req->command; 548 req->xfer[0].len = 2; 549 550 req->xfer[1].rx_buf = &req->data; 551 req->xfer[1].len = 2; 552 553 spi_message_add_tail(&req->xfer[0], &req->msg); 554 spi_message_add_tail(&req->xfer[1], &req->msg); 555 556 status = spi_sync(spi, &req->msg); 557 ret = status ? : req->data; 558 559 kfree(req); 560 561 return ret; 562 } 563 564 static int ad7879_write(struct spi_device *spi, u8 reg, u16 val) 565 { 566 struct ser_req *req; 567 int status; 568 569 req = kzalloc(sizeof *req, GFP_KERNEL); 570 if (!req) 571 return -ENOMEM; 572 573 spi_message_init(&req->msg); 574 575 req->command = (u16) AD7879_WRITECMD(reg); 576 req->xfer[0].tx_buf = &req->command; 577 req->xfer[0].len = 2; 578 579 req->data = val; 580 req->xfer[1].tx_buf = &req->data; 581 req->xfer[1].len = 2; 582 583 spi_message_add_tail(&req->xfer[0], &req->msg); 584 spi_message_add_tail(&req->xfer[1], &req->msg); 585 586 status = spi_sync(spi, &req->msg); 587 588 kfree(req); 589 590 return status; 591 } 592 593 static void ad7879_collect(struct ad7879 *ts) 594 { 595 int status = spi_sync(ts->bus, &ts->msg); 596 597 if (status) 598 dev_err(&ts->bus->dev, "spi_sync --> %d\n", status); 599 } 600 601 static void ad7879_setup_ts_def_msg(struct ad7879 *ts) 602 { 603 struct spi_message *m; 604 int i; 605 606 ts->cmd = (u16) AD7879_READCMD(AD7879_REG_XPLUS); 607 608 m = &ts->msg; 609 spi_message_init(m); 610 ts->xfer[0].tx_buf = &ts->cmd; 611 ts->xfer[0].len = 2; 612 613 spi_message_add_tail(&ts->xfer[0], m); 614 615 for (i = 0; i < AD7879_NR_SENSE; i++) { 616 ts->xfer[i + 1].rx_buf = &ts->conversion_data[i]; 617 ts->xfer[i + 1].len = 2; 618 spi_message_add_tail(&ts->xfer[i + 1], m); 619 } 620 } 621 622 static int __devinit ad7879_probe(struct spi_device *spi) 623 { 624 struct ad7879 *ts; 625 int error; 626 627 /* don't exceed max specified SPI CLK frequency */ 628 if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { 629 dev_err(&spi->dev, "SPI CLK %d Hz?\n", spi->max_speed_hz); 630 return -EINVAL; 631 } 632 633 ts = kzalloc(sizeof(struct ad7879), GFP_KERNEL); 634 if (!ts) 635 return -ENOMEM; 636 637 dev_set_drvdata(&spi->dev, ts); 638 ts->bus = spi; 639 640 ad7879_setup_ts_def_msg(ts); 641 642 error = ad7879_construct(spi, ts); 643 if (error) { 644 dev_set_drvdata(&spi->dev, NULL); 645 kfree(ts); 646 } 647 648 return error; 649 } 650 651 static int __devexit ad7879_remove(struct spi_device *spi) 652 { 653 struct ad7879 *ts = dev_get_drvdata(&spi->dev); 654 655 ad7879_destroy(spi, ts); 656 dev_set_drvdata(&spi->dev, NULL); 657 kfree(ts); 658 659 return 0; 660 } 661 662 static struct spi_driver ad7879_driver = { 663 .driver = { 664 .name = "ad7879", 665 .bus = &spi_bus_type, 666 .owner = THIS_MODULE, 667 }, 668 .probe = ad7879_probe, 669 .remove = __devexit_p(ad7879_remove), 670 .suspend = ad7879_suspend, 671 .resume = ad7879_resume, 672 }; 673 674 static int __init ad7879_init(void) 675 { 676 return spi_register_driver(&ad7879_driver); 677 } 678 module_init(ad7879_init); 679 680 static void __exit ad7879_exit(void) 681 { 682 spi_unregister_driver(&ad7879_driver); 683 } 684 module_exit(ad7879_exit); 685 686 #elif defined(CONFIG_TOUCHSCREEN_AD7879_I2C) || defined(CONFIG_TOUCHSCREEN_AD7879_I2C_MODULE) 687 688 /* All registers are word-sized. 689 * AD7879 uses a high-byte first convention. 690 */ 691 static int ad7879_read(struct i2c_client *client, u8 reg) 692 { 693 return swab16(i2c_smbus_read_word_data(client, reg)); 694 } 695 696 static int ad7879_write(struct i2c_client *client, u8 reg, u16 val) 697 { 698 return i2c_smbus_write_word_data(client, reg, swab16(val)); 699 } 700 701 static void ad7879_collect(struct ad7879 *ts) 702 { 703 int i; 704 705 for (i = 0; i < AD7879_NR_SENSE; i++) 706 ts->conversion_data[i] = ad7879_read(ts->bus, 707 AD7879_REG_XPLUS + i); 708 } 709 710 static int __devinit ad7879_probe(struct i2c_client *client, 711 const struct i2c_device_id *id) 712 { 713 struct ad7879 *ts; 714 int error; 715 716 if (!i2c_check_functionality(client->adapter, 717 I2C_FUNC_SMBUS_WORD_DATA)) { 718 dev_err(&client->dev, "SMBUS Word Data not Supported\n"); 719 return -EIO; 720 } 721 722 ts = kzalloc(sizeof(struct ad7879), GFP_KERNEL); 723 if (!ts) 724 return -ENOMEM; 725 726 i2c_set_clientdata(client, ts); 727 ts->bus = client; 728 729 error = ad7879_construct(client, ts); 730 if (error) { 731 i2c_set_clientdata(client, NULL); 732 kfree(ts); 733 } 734 735 return error; 736 } 737 738 static int __devexit ad7879_remove(struct i2c_client *client) 739 { 740 struct ad7879 *ts = dev_get_drvdata(&client->dev); 741 742 ad7879_destroy(client, ts); 743 i2c_set_clientdata(client, NULL); 744 kfree(ts); 745 746 return 0; 747 } 748 749 static const struct i2c_device_id ad7879_id[] = { 750 { "ad7879", 0 }, 751 { "ad7889", 0 }, 752 { } 753 }; 754 MODULE_DEVICE_TABLE(i2c, ad7879_id); 755 756 static struct i2c_driver ad7879_driver = { 757 .driver = { 758 .name = "ad7879", 759 .owner = THIS_MODULE, 760 }, 761 .probe = ad7879_probe, 762 .remove = __devexit_p(ad7879_remove), 763 .suspend = ad7879_suspend, 764 .resume = ad7879_resume, 765 .id_table = ad7879_id, 766 }; 767 768 static int __init ad7879_init(void) 769 { 770 return i2c_add_driver(&ad7879_driver); 771 } 772 module_init(ad7879_init); 773 774 static void __exit ad7879_exit(void) 775 { 776 i2c_del_driver(&ad7879_driver); 777 } 778 module_exit(ad7879_exit); 779 #endif 780 781 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 782 MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver"); 783 MODULE_LICENSE("GPL"); 784 MODULE_ALIAS("spi:ad7879"); 785