Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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 | |
Michael Hennerich | 4eb6f91 | 2010-03-09 20:38:47 -0800 | [diff] [blame] | 49 | #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100) |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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; |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 159 | struct spi_message msg; |
| 160 | struct spi_transfer xfer[6]; |
Oskar Schirmer | 3843384 | 2010-05-13 00:42:23 -0700 | [diff] [blame] | 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; |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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 | |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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 */ |
Oskar Schirmer | 3843384 | 2010-05-13 00:42:23 -0700 | [diff] [blame] | 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; |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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 | |
Oskar Schirmer | cd9b6fd | 2010-06-08 01:12:22 -0700 | [diff] [blame^] | 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 | |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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 | |
Michael Hennerich | 0bc69ce | 2009-04-14 10:38:36 -0700 | [diff] [blame] | 755 | err = request_irq(spi->irq, ad7877_irq, IRQF_TRIGGER_FALLING, |
| 756 | spi->dev.driver->name, ts); |
Michael Hennerich | 331b78e | 2009-03-09 20:12:52 -0700 | [diff] [blame] | 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"); |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 861 | MODULE_ALIAS("spi:ad7877"); |