drivers/input/touchscreen/xpt2046_ts.c

   1 /*
   2  * drivers/input/touchscreen/xpt2046_ts.c - driver for rk2818 spi xpt2046 device and console
   3  *
   4  * Copyright (C) 2010 ROCKCHIP, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/hwmon.h>
  17 #include <linux/init.h>
  18 #include <linux/err.h>
  19 #include <linux/delay.h>
  20 #include <linux/input.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/slab.h>
  23 #include <linux/gpio.h>
  24 #include <linux/spi/spi.h>
  25 #include <asm/irq.h>
  26
  27 #include "xpt2046_ts.h"
  28
  29 /*
  30  * This code has been heavily tested on a Nokia 770, and lightly
  31  * tested on other xpt2046 devices (OSK/Mistral, Lubbock).
  32  * TSC2046 is just newer xpt2046 silicon.
  33  * Support for ads7843 tested on Atmel at91sam926x-EK.
  34  * Support for ads7845 has only been stubbed in.
  35  *
  36  * IRQ handling needs a workaround because of a shortcoming in handling
  37  * edge triggered IRQs on some platforms like the OMAP1/2. These
  38  * platforms don't handle the ARM lazy IRQ disabling properly, thus we
  39  * have to maintain our own SW IRQ disabled status. This should be
  40  * removed as soon as the affected platform's IRQ handling is fixed.
  41  *
  42  * app note sbaa036 talks in more detail about accurate sampling...
  43  * that ought to help in situations like LCDs inducing noise (which
  44  * can also be helped by using synch signals) and more generally.
  45  * This driver tries to utilize the measures described in the app
  46  * note. The strength of filtering can be set in the board-* specific
  47  * files.
  48  */
  49 #define XPT2046_DEBUG                   0
  50 #if XPT2046_DEBUG
  51         #define xpt2046printk(msg...)   printk(msg);
  52 #else
  53         #define xpt2046printk(msg...)
  54 #endif
  55 #define LCD_MAX_LENGTH                          800
  56 #define LCD_MAX_WIDTH                           480
  57 #define PT2046_TOUCH_AD_LEFT            3855
  58 #define PT2046_TOUCH_AD_RIGHT           260
  59 #define PT2046_TOUCH_AD_TOP             300
  60 #define PT2046_TOUCH_AD_BOTTOM  3755
  61 #define AD_TO_X(adx)    (LCD_MAX_WIDTH * (adx - PT2046_TOUCH_AD_TOP) / ( PT2046_TOUCH_AD_BOTTOM  - PT2046_TOUCH_AD_TOP ))
  62 #define AD_TO_Y(ady)    (LCD_MAX_LENGTH * (PT2046_TOUCH_AD_LEFT - ady) / (PT2046_TOUCH_AD_LEFT - PT2046_TOUCH_AD_RIGHT))
  63
  64 #define TS_POLL_DELAY   (10 * 1000000)  /* ns delay before the first sample */
  65 #define TS_POLL_PERIOD  (20 * 1000000)  /* ns delay between samples */
  66
  67 #define DEBOUNCE_REPTIME  3
  68 /* this driver doesn't aim at the peak continuous sample rate */
  69 #define SAMPLE_BITS     (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */)
  70
  71 struct ts_event {
  72         /* For portability, we can't read 12 bit values using SPI (which
  73          * would make the controller deliver them as native byteorder u16
  74          * with msbs zeroed).  Instead, we read them as two 8-bit values,
  75          * *** WHICH NEED BYTESWAPPING *** and range adjustment.
  76          */
  77         u16     x;
  78         u16     y;
  79         int     ignore;
  80 };
  81
  82 /*
  83  * We allocate this separately to avoid cache line sharing issues when
  84  * driver is used with DMA-based SPI controllers (like atmel_spi) on
  85  * systems where main memory is not DMA-coherent (most non-x86 boards).
  86  */
  87 struct xpt2046_packet {
  88         u8                      read_x, read_y, pwrdown;
  89         u16                     dummy;          /* for the pwrdown read */
  90         struct ts_event         tc;
  91 };
  92
  93 struct xpt2046 {
  94         struct input_dev        *input;
  95         char                    phys[32];
  96         char                    name[32];
  97
  98         struct spi_device       *spi;
  99
 100         u16                     model;
 101         bool                    swap_xy;
 102
 103         struct xpt2046_packet   *packet;
 104
 105         struct spi_transfer     xfer[18];
 106         struct spi_message      msg[5];
 107         struct spi_message      *last_msg;
 108         int                     msg_idx;
 109         int                     read_cnt;
 110         int                     read_rep;
 111         int                     last_read;
 112
 113         u16                     debounce_max;
 114         u16                     debounce_tol;
 115         u16                     debounce_rep;
 116
 117         u16                     penirq_recheck_delay_usecs;
 118
 119         spinlock_t              lock;
 120         struct hrtimer          timer;
 121         unsigned                pendown:1;      /* P: lock */
 122         unsigned                pending:1;      /* P: lock */
 123 // FIXME remove "irq_disabled"
 124         unsigned                irq_disabled:1; /* P: lock */
 125         unsigned                disabled:1;
 126         unsigned                is_suspended:1;
 127
 128         int                     (*filter)(void *data, int data_idx, int *val);
 129         void                    *filter_data;
 130         void                    (*filter_cleanup)(void *data);
 131         int                     (*get_pendown_state)(void);
 132         int                     gpio_pendown;
 133
 134         void                    (*wait_for_sync)(void);
 135 };
 136
 137 /* leave chip selected when we're done, for quicker re-select? */
 138 #if     0
 139 #define CS_CHANGE(xfer) ((xfer).cs_change = 1)
 140 #else
 141 #define CS_CHANGE(xfer) ((xfer).cs_change = 0)
 142 #endif
 143
 144 /*--------------------------------------------------------------------------*/
 145
 146 /* The xpt2046 has touchscreen and other sensors.
 147  * Earlier xpt2046 chips are somewhat compatible.
 148  */
 149 #define XPT2046_START                   (1 << 7)
 150 #define XPT2046_A2A1A0_d_y              (1 << 4)        /* differential */
 151 #define XPT2046_A2A1A0_d_z1             (3 << 4)        /* differential */
 152 #define XPT2046_A2A1A0_d_z2             (4 << 4)        /* differential */
 153 #define XPT2046_A2A1A0_d_x              (5 << 4)        /* differential */
 154 #define XPT2046_A2A1A0_temp0    (0 << 4)        /* non-differential */
 155 #define XPT2046_A2A1A0_vbatt    (2 << 4)        /* non-differential */
 156 #define XPT2046_A2A1A0_vaux             (6 << 4)        /* non-differential */
 157 #define XPT2046_A2A1A0_temp1    (7 << 4)        /* non-differential */
 158 #define XPT2046_8_BIT                   (1 << 3)
 159 #define XPT2046_12_BIT                  (0 << 3)
 160 #define XPT2046_SER                             (1 << 2)        /* non-differential */
 161 #define XPT2046_DFR                             (0 << 2)        /* differential */
 162 #define XPT2046_PD10_PDOWN              (0 << 0)        /* lowpower mode + penirq */
 163 #define XPT2046_PD10_ADC_ON             (1 << 0)        /* ADC on */
 164 #define XPT2046_PD10_REF_ON             (2 << 0)        /* vREF on + penirq */
 165 #define XPT2046_PD10_ALL_ON             (3 << 0)        /* ADC + vREF on */
 166
 167 #define MAX_12BIT       ((1<<12)-1)
 168
 169 /* leave ADC powered up (disables penirq) between differential samples */
 170 #define READ_12BIT_DFR(x, adc, vref) (XPT2046_START | XPT2046_A2A1A0_d_ ## x \
 171         | XPT2046_12_BIT | XPT2046_DFR | \
 172         (adc ? XPT2046_PD10_ADC_ON : 0) | (vref ? XPT2046_PD10_REF_ON : 0))
 173
 174 #define READ_Y(vref)    (READ_12BIT_DFR(y,  1, vref))
 175 #define READ_Z1(vref)   (READ_12BIT_DFR(z1, 1, vref))
 176 #define READ_Z2(vref)   (READ_12BIT_DFR(z2, 1, vref))
 177
 178 #define READ_X(vref)    (READ_12BIT_DFR(x,  1, vref))
 179 #define PWRDOWN         (READ_12BIT_DFR(y,  0, 0))      /* LAST */
 180
 181 /* single-ended samples need to first power up reference voltage;
 182  * we leave both ADC and VREF powered
 183  */
 184 #define READ_12BIT_SER(x) (XPT2046_START | XPT2046_A2A1A0_ ## x \
 185         | XPT2046_12_BIT | XPT2046_SER)
 186
 187 #define REF_ON  (READ_12BIT_DFR(x, 1, 1))
 188 #define REF_OFF (READ_12BIT_DFR(y, 0, 0))
 189
 190 /*--------------------------------------------------------------------------*/
 191 /*
 192  * touchscreen sensors  use differential conversions.
 193  */
 194
 195 struct dfr_req {
 196         u8                      command;
 197         u8                      pwrdown;
 198         u16                     dummy;          /* for the pwrdown read */
 199         __be16                  sample;
 200         struct spi_message      msg;
 201         struct spi_transfer     xfer[4];
 202 };
 203
 204 static struct xpt2046_platform_data xpt2046_info = {
 205         .model                  = 2046,
 206         .keep_vref_on   = 1,
 207         .swap_xy                = 1,
 208         .x_min                  = 0,
 209         .x_max                  = 800,
 210         .y_min                  = 0,
 211         .y_max                  = 480,
 212         .debounce_max           = 7,
 213         .debounce_rep           = DEBOUNCE_REPTIME,
 214         .debounce_tol           = 20,
 215         .gpio_pendown           = RK2818_PIN_PE3,
 216         .penirq_recheck_delay_usecs = 1,
 217
 218 };
 219 static void xpt2046_enable(struct xpt2046 *ts);
 220 static void xpt2046_disable(struct xpt2046 *ts);
 221
 222 static int device_suspended(struct device *dev)
 223 {
 224         struct xpt2046 *ts = dev_get_drvdata(dev);
 225         return ts->is_suspended || ts->disabled;
 226 }
 227
 228 static int xpt2046_read12_dfr(struct device *dev, unsigned command)
 229 {
 230         struct spi_device       *spi = to_spi_device(dev);
 231         struct xpt2046          *ts = dev_get_drvdata(dev);
 232         struct dfr_req          *req = kzalloc(sizeof *req, GFP_KERNEL);
 233         int                     status;
 234
 235         if (!req)
 236                 return -ENOMEM;
 237
 238         spi_message_init(&req->msg);
 239
 240         /* take sample */
 241         req->command = (u8) command;
 242         req->xfer[0].tx_buf = &req->command;
 243         req->xfer[0].len = 1;
 244         spi_message_add_tail(&req->xfer[0], &req->msg);
 245
 246         req->xfer[1].rx_buf = &req->sample;
 247         req->xfer[1].len = 2;
 248         spi_message_add_tail(&req->xfer[1], &req->msg);
 249
 250         /* converter in low power mode & enable PENIRQ */
 251         req->pwrdown= PWRDOWN;
 252         req->xfer[2].tx_buf = &req->pwrdown;
 253         req->xfer[2].len = 1;
 254         spi_message_add_tail(&req->xfer[2], &req->msg);
 255
 256         req->xfer[3].rx_buf = &req->dummy;
 257         req->xfer[3].len = 2;
 258         CS_CHANGE(req->xfer[3]);
 259         spi_message_add_tail(&req->xfer[3], &req->msg);
 260
 261         ts->irq_disabled = 1;
 262         disable_irq(spi->irq);
 263         status = spi_sync(spi, &req->msg);
 264         ts->irq_disabled = 0;
 265         enable_irq(spi->irq);
 266
 267         if (status == 0) {
 268                 /* on-wire is a must-ignore bit, a BE12 value, then padding */
 269                 status = be16_to_cpu(req->sample);
 270                 status = status >> 3;
 271                 status &= 0x0fff;
 272                 xpt2046printk("***>%s:status=%d\n",__FUNCTION__,status);
 273         }
 274
 275         kfree(req);
 276         return status;
 277 }
 278
 279
 280
 281 /*--------------------------------------------------------------------------*/
 282
 283 static int get_pendown_state(struct xpt2046 *ts)
 284 {
 285         if (ts->get_pendown_state)
 286                 return ts->get_pendown_state();
 287
 288         return !gpio_get_value(ts->gpio_pendown);
 289 }
 290
 291 static void null_wait_for_sync(void)
 292 {
 293
 294 }
 295
 296 /*
 297  * PENIRQ only kicks the timer.  The timer only reissues the SPI transfer,
 298  * to retrieve touchscreen status.
 299  *
 300  * The SPI transfer completion callback does the real work.  It reports
 301  * touchscreen events and reactivates the timer (or IRQ) as appropriate.
 302  */
 303
 304 static void xpt2046_rx(void *xpt)
 305 {
 306         struct xpt2046          *ts = xpt;
 307         struct xpt2046_packet   *packet = ts->packet;
 308         unsigned                Rt = 1;
 309         u16                     x, y;
 310
 311         /* xpt2046_rx_val() did in-place conversion (including byteswap) from
 312          * on-the-wire format as part of debouncing to get stable readings.
 313          */
 314         x = packet->tc.x;
 315         y = packet->tc.y;
 316
 317         xpt2046printk("***>%s:x=%d,y=%d\n",__FUNCTION__,x,y);
 318
 319         /* range filtering */
 320         if (x == MAX_12BIT)
 321                 x = 0;
 322
 323         /* Sample found inconsistent by debouncing or pressure is beyond
 324          * the maximum. Don't report it to user space, repeat at least
 325          * once more the measurement
 326          */
 327         if (packet->tc.ignore) {
 328
 329                 xpt2046printk("***>%s:ignored=%d\n",__FUNCTION__,packet->tc.ignore);
 330
 331                 hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
 332                               HRTIMER_MODE_REL);
 333                 return;
 334         }
 335
 336         /* Maybe check the pendown state before reporting. This discards
 337          * false readings when the pen is lifted.
 338          */
 339         if (ts->penirq_recheck_delay_usecs) {
 340                 udelay(ts->penirq_recheck_delay_usecs);
 341                 if (!get_pendown_state(ts))
 342                 {
 343                         xpt2046printk("***>%s:get_pendown_state(ts)==0,discard false reading\n",__FUNCTION__);
 344                         Rt = 0;
 345                 }
 346         }
 347
 348         /* NOTE: We can't rely on the pressure to determine the pen down
 349          * state, even this controller has a pressure sensor.  The pressure
 350          * value can fluctuate for quite a while after lifting the pen and
 351          * in some cases may not even settle at the expected value.
 352          *
 353          * The only safe way to check for the pen up condition is in the
 354          * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
 355          */
 356         if (Rt) {
 357                 struct input_dev *input = ts->input;
 358                 if (!ts->pendown) {
 359                         input_report_key(input, BTN_TOUCH, 1);
 360                         ts->pendown = 1;
 361                         xpt2046printk("***>%s:input_report_key(pen down)\n",__FUNCTION__);
 362                 }
 363
 364                 x =  AD_TO_X(x);
 365                 y =  AD_TO_Y(y);
 366
 367                 if (ts->swap_xy)
 368                         swap(x, y);
 369
 370                 input_report_abs(input, ABS_X, x);
 371                 input_report_abs(input, ABS_Y, y);
 372
 373                 input_sync(input);
 374                 xpt2046printk("***>%s:input_report_abs(%4d/%4d)\n",__FUNCTION__,x, y);
 375         }
 376
 377         hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
 378                         HRTIMER_MODE_REL);
 379 }
 380
 381 static int xpt2046_debounce(void *xpt, int data_idx, int *val)
 382 {
 383         struct xpt2046          *ts = xpt;
 384         static int average_val[2];
 385
 386
 387         xpt2046printk("***>%s:%d,%d,%d,%d,%d,%d,%d,%d\n",__FUNCTION__,
 388                 data_idx,ts->last_read,
 389           ts->read_cnt,ts->debounce_max,
 390                 abs(ts->last_read - *val),ts->debounce_tol,
 391                 ts->read_rep,ts->debounce_rep);
 392
 393         if(*val == 4095 || *val == 0)
 394         {
 395                 ts->read_cnt = 0;
 396                 ts->last_read = 0;
 397                 memset(average_val,0,sizeof(average_val));
 398                 xpt2046printk("***>%s:*val == 4095 || *val == 0\n",__FUNCTION__);
 399                 return XPT2046_FILTER_IGNORE;
 400         }
 401         /* discard the first sample. */
 402         if(!ts->read_cnt)
 403         {
 404                 ts->read_cnt++;
 405                 return XPT2046_FILTER_REPEAT;
 406         }
 407
 408         if (ts->read_cnt==1 || (abs(ts->last_read - *val) > ts->debounce_tol)) {
 409                 /* Start over collecting consistent readings. */
 410                 ts->read_rep = 1;
 411                 average_val[data_idx] = *val;
 412                 /* Repeat it, if this was the first read or the read
 413                  * wasn't consistent enough. */
 414                 if (ts->read_cnt < ts->debounce_max) {
 415                         ts->last_read = *val;
 416                         ts->read_cnt++;
 417                         return XPT2046_FILTER_REPEAT;
 418                 } else {
 419                         /* Maximum number of debouncing reached and still
 420                          * not enough number of consistent readings. Abort
 421                          * the whole sample, repeat it in the next sampling
 422                          * period.
 423                          */
 424                         ts->read_cnt = 0;
 425                         ts->last_read = 0;
 426                         memset(average_val,0,sizeof(average_val));
 427                         xpt2046printk("***>%s:XPT2046_FILTER_IGNORE\n",__FUNCTION__);
 428                         return XPT2046_FILTER_IGNORE;
 429                 }
 430         }
 431         else {
 432                 average_val[data_idx] += *val;
 433
 434                 if (++ts->read_rep >= ts->debounce_rep) {
 435                         /* Got a good reading for this coordinate,
 436                          * go for the next one. */
 437                         ts->read_cnt = 0;
 438                         ts->read_rep = 0;
 439                         ts->last_read = 0;
 440                         *val = average_val[data_idx]/(ts->debounce_rep);
 441                         return XPT2046_FILTER_OK;
 442                 } else {
 443                         /* Read more values that are consistent. */
 444                         ts->read_cnt++;
 445
 446                         return XPT2046_FILTER_REPEAT;
 447                 }
 448         }
 449 }
 450
 451 static int xpt2046_no_filter(void *xpt, int data_idx, int *val)
 452 {
 453         return XPT2046_FILTER_OK;
 454 }
 455
 456 static void xpt2046_rx_val(void *xpt)
 457 {
 458         struct xpt2046 *ts = xpt;
 459         struct xpt2046_packet *packet = ts->packet;
 460         struct spi_message *m;
 461         struct spi_transfer *t;
 462         int val;
 463         int action;
 464         int status;
 465
 466         m = &ts->msg[ts->msg_idx];
 467         t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
 468
 469         /* adjust:  on-wire is a must-ignore bit, a BE12 value, then padding;
 470          * built from two 8 bit values written msb-first.
 471          */
 472         val = (be16_to_cpup((__be16 *)t->rx_buf) >> 3) & 0x0fff;
 473
 474         xpt2046printk("***>%s:value=%d\n",__FUNCTION__,val);
 475
 476         action = ts->filter(ts->filter_data, ts->msg_idx, &val);
 477         switch (action) {
 478         case XPT2046_FILTER_REPEAT:
 479                 break;
 480         case XPT2046_FILTER_IGNORE:
 481                 packet->tc.ignore = 1;
 482                 /* Last message will contain xpt2046_rx() as the
 483                  * completion function.
 484                  */
 485                 m = ts->last_msg;
 486                 break;
 487         case XPT2046_FILTER_OK:
 488                 *(u16 *)t->rx_buf = val;
 489                 packet->tc.ignore = 0;
 490                 m = &ts->msg[++ts->msg_idx];
 491                 break;
 492         default:
 493                 BUG();
 494         }
 495         ts->wait_for_sync();
 496         status = spi_async(ts->spi, m);
 497         if (status)
 498                 dev_err(&ts->spi->dev, "spi_async --> %d\n",
 499                                 status);
 500 }
 501
 502 static enum hrtimer_restart xpt2046_timer(struct hrtimer *handle)
 503 {
 504         struct xpt2046  *ts = container_of(handle, struct xpt2046, timer);
 505         int             status = 0;
 506
 507         spin_lock(&ts->lock);
 508
 509         if (unlikely(!get_pendown_state(ts) ||
 510                      device_suspended(&ts->spi->dev))) {
 511                 if (ts->pendown) {
 512                         struct input_dev *input = ts->input;
 513                         input_report_key(input, BTN_TOUCH, 0);
 514                         input_sync(input);
 515
 516                         ts->pendown = 0;
 517
 518                         xpt2046printk("***>%s:input_report_key(The touchscreen up)\n",__FUNCTION__);
 519                 }
 520
 521                 /* measurement cycle ended */
 522                 if (!device_suspended(&ts->spi->dev)) {
 523                         xpt2046printk("***>%s:device_suspended==0\n",__FUNCTION__);
 524                         ts->irq_disabled = 0;
 525                         enable_irq(ts->spi->irq);
 526                 }
 527                 ts->pending = 0;
 528         } else {
 529                 /* pen is still down, continue with the measurement */
 530                 xpt2046printk("***>%s:pen is still down, continue with the measurement\n",__FUNCTION__);
 531                 ts->msg_idx = 0;
 532                 ts->wait_for_sync();
 533                 status = spi_async(ts->spi, &ts->msg[0]);
 534                 if (status)
 535                         dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
 536         }
 537
 538         spin_unlock(&ts->lock);
 539         return HRTIMER_NORESTART;
 540 }
 541
 542 static irqreturn_t xpt2046_irq(int irq, void *handle)
 543 {
 544         struct xpt2046 *ts = handle;
 545         unsigned long flags;
 546
 547         xpt2046printk("***>%s.....%s.....%d\n",__FILE__,__FUNCTION__,__LINE__);
 548
 549         spin_lock_irqsave(&ts->lock, flags);
 550
 551         if (likely(get_pendown_state(ts))) {
 552                 if (!ts->irq_disabled) {
 553                         /* The ARM do_simple_IRQ() dispatcher doesn't act
 554                          * like the other dispatchers:  it will report IRQs
 555                          * even after they've been disabled.  We work around
 556                          * that here.  (The "generic irq" framework may help...)
 557                          */
 558                         ts->irq_disabled = 1;
 559                         disable_irq_nosync(ts->spi->irq);
 560                         ts->pending = 1;
 561                         hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
 562                                         HRTIMER_MODE_REL);
 563                 }
 564         }
 565         spin_unlock_irqrestore(&ts->lock, flags);
 566
 567         return IRQ_HANDLED;
 568 }
 569
 570 /*--------------------------------------------------------------------------*/
 571
 572 /* Must be called with ts->lock held */
 573 static void xpt2046_disable(struct xpt2046 *ts)
 574 {
 575         if (ts->disabled)
 576                 return;
 577
 578         ts->disabled = 1;
 579
 580         /* are we waiting for IRQ, or polling? */
 581         if (!ts->pending) {
 582                 ts->irq_disabled = 1;
 583                 disable_irq(ts->spi->irq);
 584         } else {
 585                 /* the timer will run at least once more, and
 586                  * leave everything in a clean state, IRQ disabled
 587                  */
 588                 while (ts->pending) {
 589                         spin_unlock_irq(&ts->lock);
 590                         msleep(1);
 591                         spin_lock_irq(&ts->lock);
 592                 }
 593         }
 594
 595         /* we know the chip's in lowpower mode since we always
 596          * leave it that way after every request
 597          */
 598 }
 599
 600 /* Must be called with ts->lock held */
 601 static void xpt2046_enable(struct xpt2046 *ts)
 602 {
 603         if (!ts->disabled)
 604                 return;
 605
 606         ts->disabled = 0;
 607         ts->irq_disabled = 0;
 608         enable_irq(ts->spi->irq);
 609 }
 610
 611 static int xpt2046_suspend(struct spi_device *spi, pm_message_t message)
 612 {
 613         struct xpt2046 *ts = dev_get_drvdata(&spi->dev);
 614
 615         spin_lock_irq(&ts->lock);
 616
 617         ts->is_suspended = 1;
 618         xpt2046_disable(ts);
 619
 620         spin_unlock_irq(&ts->lock);
 621
 622         return 0;
 623
 624 }
 625
 626 static int xpt2046_resume(struct spi_device *spi)
 627 {
 628         struct xpt2046 *ts = dev_get_drvdata(&spi->dev);
 629
 630         spin_lock_irq(&ts->lock);
 631
 632         ts->is_suspended = 0;
 633         xpt2046_enable(ts);
 634
 635         spin_unlock_irq(&ts->lock);
 636
 637         return 0;
 638 }
 639
 640 static int __devinit setup_pendown(struct spi_device *spi, struct xpt2046 *ts)
 641 {
 642         struct xpt2046_platform_data *pdata = spi->dev.platform_data;
 643         int err;
 644
 645         /* REVISIT when the irq can be triggered active-low, or if for some
 646          * reason the touchscreen isn't hooked up, we don't need to access
 647          * the pendown state.
 648          */
 649         if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
 650                 dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
 651                 return -EINVAL;
 652         }
 653
 654         if (pdata->get_pendown_state) {
 655                 ts->get_pendown_state = pdata->get_pendown_state;
 656                 return 0;
 657         }
 658
 659         err = gpio_request(pdata->gpio_pendown, "xpt2046_pendown");
 660         if (err) {
 661                 dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
 662                                 pdata->gpio_pendown);
 663                 return err;
 664         }
 665
 666         ts->gpio_pendown = pdata->gpio_pendown;
 667         return 0;
 668 }
 669
 670 static int __devinit xpt2046_probe(struct spi_device *spi)
 671 {
 672         struct xpt2046                  *ts;
 673         struct xpt2046_packet           *packet;
 674         struct input_dev                *input_dev;
 675         struct xpt2046_platform_data    *pdata = spi->dev.platform_data;
 676         struct spi_message              *m;
 677         struct spi_transfer             *x;
 678         int                             vref;
 679         int                             err;
 680
 681
 682
 683         if (!spi->irq) {
 684                 dev_dbg(&spi->dev, "no IRQ?\n");
 685                 return -ENODEV;
 686         }
 687         else{
 688                 spi->irq = gpio_to_irq(spi->irq);
 689                 dev_dbg(&spi->dev, "no IRQ?\n");
 690         }
 691
 692         if (!pdata) {
 693                 spi->dev.platform_data = &xpt2046_info;
 694                 pdata = spi->dev.platform_data;
 695         }
 696
 697         /* don't exceed max specified sample rate */
 698         if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
 699                 dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
 700                                 (spi->max_speed_hz/SAMPLE_BITS)/1000);
 701                 return -EINVAL;
 702         }
 703
 704         /* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except
 705          * that even if the hardware can do that, the SPI controller driver
 706          * may not.  So we stick to very-portable 8 bit words, both RX and TX.
 707          */
 708         spi->bits_per_word = 8;
 709         spi->mode = SPI_MODE_0;
 710         err = spi_setup(spi);
 711         if (err < 0)
 712                 return err;
 713
 714         ts = kzalloc(sizeof(struct xpt2046), GFP_KERNEL);
 715         packet = kzalloc(sizeof(struct xpt2046_packet), GFP_KERNEL);
 716         input_dev = input_allocate_device();
 717         if (!ts || !packet || !input_dev) {
 718                 err = -ENOMEM;
 719                 goto err_free_mem;
 720         }
 721
 722         dev_set_drvdata(&spi->dev, ts);
 723
 724         ts->packet = packet;
 725         ts->spi = spi;
 726         ts->input = input_dev;
 727         ts->swap_xy = pdata->swap_xy;
 728
 729         hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 730         ts->timer.function = xpt2046_timer;
 731
 732         spin_lock_init(&ts->lock);
 733
 734         ts->model = pdata->model ? : 2046;
 735
 736         if (pdata->filter != NULL) {
 737                 if (pdata->filter_init != NULL) {
 738                         err = pdata->filter_init(pdata, &ts->filter_data);
 739                         if (err < 0)
 740                                 goto err_free_mem;
 741                 }
 742                 ts->filter = pdata->filter;
 743                 ts->filter_cleanup = pdata->filter_cleanup;
 744         } else if (pdata->debounce_max) {
 745                 ts->debounce_max = pdata->debounce_max;
 746                 if (ts->debounce_max < DEBOUNCE_REPTIME)
 747                         ts->debounce_max = DEBOUNCE_REPTIME;
 748                 ts->debounce_tol = pdata->debounce_tol;
 749                 ts->debounce_rep = pdata->debounce_rep;
 750                 ts->filter = xpt2046_debounce;
 751                 ts->filter_data = ts;
 752         } else
 753                 ts->filter = xpt2046_no_filter;
 754
 755         err = setup_pendown(spi, ts);
 756         if (err)
 757                 goto err_cleanup_filter;
 758
 759         if (pdata->penirq_recheck_delay_usecs)
 760                 ts->penirq_recheck_delay_usecs =
 761                                 pdata->penirq_recheck_delay_usecs;
 762
 763         ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
 764
 765         snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
 766         snprintf(ts->name, sizeof(ts->name), "XPT%d Touchscreen", ts->model);
 767
 768         input_dev->name = ts->name;
 769         input_dev->phys = ts->phys;
 770         input_dev->dev.parent = &spi->dev;
 771
 772         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 773         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 774         input_set_abs_params(input_dev, ABS_X,
 775                         pdata->x_min ? : 0,
 776                         pdata->x_max ? : MAX_12BIT,
 777                         0, 0);
 778         input_set_abs_params(input_dev, ABS_Y,
 779                         pdata->y_min ? : 0,
 780                         pdata->y_max ? : MAX_12BIT,
 781                         0, 0);
 782
 783         vref = pdata->keep_vref_on;
 784
 785         /* set up the transfers to read touchscreen state; this assumes we
 786          * use formula #2 for pressure, not #3.
 787          */
 788         m = &ts->msg[0];
 789         x = ts->xfer;
 790
 791         spi_message_init(m);
 792
 793         /* y- still on; turn on only y+ (and ADC) */
 794         packet->read_y = READ_Y(vref);
 795         x->tx_buf = &packet->read_y;
 796         x->len = 1;
 797         spi_message_add_tail(x, m);
 798
 799         x++;
 800         x->rx_buf = &packet->tc.y;
 801         x->len = 2;
 802         spi_message_add_tail(x, m);
 803
 804         m->complete = xpt2046_rx_val;
 805         m->context = ts;
 806
 807         m++;
 808         spi_message_init(m);
 809
 810         /* turn y- off, x+ on, then leave in lowpower */
 811         x++;
 812         packet->read_x = READ_X(vref);
 813         x->tx_buf = &packet->read_x;
 814         x->len = 1;
 815         spi_message_add_tail(x, m);
 816
 817         x++;
 818         x->rx_buf = &packet->tc.x;
 819         x->len = 2;
 820         spi_message_add_tail(x, m);
 821
 822         m->complete = xpt2046_rx_val;
 823         m->context = ts;
 824
 825         /* power down */
 826         m++;
 827         spi_message_init(m);
 828
 829         x++;
 830         packet->pwrdown = PWRDOWN;
 831         x->tx_buf = &packet->pwrdown;
 832         x->len = 1;
 833         spi_message_add_tail(x, m);
 834
 835         x++;
 836         x->rx_buf = &packet->dummy;
 837         x->len = 2;
 838         CS_CHANGE(*x);
 839         spi_message_add_tail(x, m);
 840
 841         m->complete = xpt2046_rx;
 842         m->context = ts;
 843
 844         ts->last_msg = m;
 845
 846         if (request_irq(spi->irq, xpt2046_irq, IRQF_TRIGGER_FALLING,
 847                         spi->dev.driver->name, ts)) {
 848                 printk("%s:trying pin change workaround on irq %d\n",__FUNCTION__,spi->irq);
 849                 err = request_irq(spi->irq, xpt2046_irq,
 850                                   IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 851                                   spi->dev.driver->name, ts);
 852                 if (err) {
 853                         dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
 854                         goto err_free_gpio;
 855                 }
 856         }
 857         xpt2046printk("***>%s:touchscreen irq %d\n",__FUNCTION__,spi->irq);
 858
 859         /* take a first sample, leaving nPENIRQ active and vREF off; avoid
 860          * the touchscreen, in case it's not connected.
 861          */
 862         xpt2046_read12_dfr(&spi->dev,READ_X(1));
 863
 864         err = input_register_device(input_dev);
 865         if (err)
 866                 goto err_remove_attr_group;
 867   printk("xpt2046_ts: driver initialized\n");
 868         return 0;
 869
 870  err_remove_attr_group:
 871         free_irq(spi->irq, ts);
 872  err_free_gpio:
 873         if (ts->gpio_pendown != -1)
 874                 gpio_free(ts->gpio_pendown);
 875  err_cleanup_filter:
 876         if (ts->filter_cleanup)
 877                 ts->filter_cleanup(ts->filter_data);
 878  err_free_mem:
 879         input_free_device(input_dev);
 880         kfree(packet);
 881         kfree(ts);
 882         return err;
 883 }
 884
 885 static int __devexit xpt2046_remove(struct spi_device *spi)
 886 {
 887         struct xpt2046          *ts = dev_get_drvdata(&spi->dev);
 888
 889         input_unregister_device(ts->input);
 890
 891         xpt2046_suspend(spi, PMSG_SUSPEND);
 892
 893         free_irq(ts->spi->irq, ts);
 894         /* suspend left the IRQ disabled */
 895         enable_irq(ts->spi->irq);
 896
 897         if (ts->gpio_pendown != -1)
 898                 gpio_free(ts->gpio_pendown);
 899
 900         if (ts->filter_cleanup)
 901                 ts->filter_cleanup(ts->filter_data);
 902
 903         kfree(ts->packet);
 904         kfree(ts);
 905
 906         dev_dbg(&spi->dev, "unregistered touchscreen\n");
 907         return 0;
 908 }
 909
 910 static struct spi_driver xpt2046_driver = {
 911         .driver = {
 912                 .name   = "xpt2046_ts",
 913                 .bus    = &spi_bus_type,
 914                 .owner  = THIS_MODULE,
 915         },
 916         .probe          = xpt2046_probe,
 917         .remove         = __devexit_p(xpt2046_remove),
 918         .suspend        = xpt2046_suspend,
 919         .resume         = xpt2046_resume,
 920 };
 921
 922 static int __init xpt2046_init(void)
 923 {
 924         return spi_register_driver(&xpt2046_driver);
 925 }
 926 module_init(xpt2046_init);
 927
 928 static void __exit xpt2046_exit(void)
 929 {
 930         spi_unregister_driver(&xpt2046_driver);
 931 }
 932 module_exit(xpt2046_exit);
 933
 934 MODULE_DESCRIPTION("rk2818 spi xpt2046 TouchScreen Driver");
 935 MODULE_LICENSE("GPL");
 936 MODULE_ALIAS("spi:xpt2046");