drivers/input/touchscreen/corgi_ts.c

   1 /*
   2  *  Touchscreen driver for Sharp SL-C7xx and SL-Cxx00 models
   3  *
   4  *  Copyright (c) 2004-2005 Richard Purdie
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License version 2 as
   8  *  published by the Free Software Foundation.
   9  *
  10  */
  11
  12
  13 #include <linux/delay.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/init.h>
  16 #include <linux/input.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/module.h>
  19 #include <linux/slab.h>
  20 #include <linux/irq.h>
  21
  22 #include <asm/arch/sharpsl.h>
  23 #include <asm/arch/hardware.h>
  24 #include <asm/arch/pxa-regs.h>
  25
  26
  27 #define PWR_MODE_ACTIVE         0
  28 #define PWR_MODE_SUSPEND        1
  29
  30 #define X_AXIS_MAX              3830
  31 #define X_AXIS_MIN              150
  32 #define Y_AXIS_MAX              3830
  33 #define Y_AXIS_MIN              190
  34 #define PRESSURE_MIN            0
  35 #define PRESSURE_MAX            15000
  36
  37 struct ts_event {
  38         short pressure;
  39         short x;
  40         short y;
  41 };
  42
  43 struct corgi_ts {
  44         struct input_dev *input;
  45         struct timer_list timer;
  46         struct ts_event tc;
  47         int pendown;
  48         int power_mode;
  49         int irq_gpio;
  50         struct corgits_machinfo *machinfo;
  51 };
  52
  53 #ifdef CONFIG_PXA25x
  54 #define CCNT(a)         asm volatile ("mrc p14, 0, %0, C1, C0, 0" : "=r"(a))
  55 #define PMNC_GET(x)     asm volatile ("mrc p14, 0, %0, C0, C0, 0" : "=r"(x))
  56 #define PMNC_SET(x)     asm volatile ("mcr p14, 0, %0, C0, C0, 0" : : "r"(x))
  57 #endif
  58 #ifdef CONFIG_PXA27x
  59 #define CCNT(a)         asm volatile ("mrc p14, 0, %0, C1, C1, 0" : "=r"(a))
  60 #define PMNC_GET(x)     asm volatile ("mrc p14, 0, %0, C0, C1, 0" : "=r"(x))
  61 #define PMNC_SET(x)     asm volatile ("mcr p14, 0, %0, C0, C1, 0" : : "r"(x))
  62 #endif
  63
  64 /* ADS7846 Touch Screen Controller bit definitions */
  65 #define ADSCTRL_PD0             (1u << 0)       /* PD0 */
  66 #define ADSCTRL_PD1             (1u << 1)       /* PD1 */
  67 #define ADSCTRL_DFR             (1u << 2)       /* SER/DFR */
  68 #define ADSCTRL_MOD             (1u << 3)       /* Mode */
  69 #define ADSCTRL_ADR_SH  4       /* Address setting */
  70 #define ADSCTRL_STS             (1u << 7)       /* Start Bit */
  71
  72 /* External Functions */
  73 extern unsigned int get_clk_frequency_khz(int info);
  74
  75 static unsigned long calc_waittime(struct corgi_ts *corgi_ts)
  76 {
  77         unsigned long hsync_len = corgi_ts->machinfo->get_hsync_len();
  78
  79         if (hsync_len)
  80                 return get_clk_frequency_khz(0)*1000/hsync_len;
  81         else
  82                 return 0;
  83 }
  84
  85 static int sync_receive_data_send_cmd(struct corgi_ts *corgi_ts, int doRecive, int doSend,
  86                 unsigned int address, unsigned long wait_time)
  87 {
  88         unsigned long timer1 = 0, timer2, pmnc = 0;
  89         int pos = 0;
  90
  91         if (wait_time && doSend) {
  92                 PMNC_GET(pmnc);
  93                 if (!(pmnc & 0x01))
  94                         PMNC_SET(0x01);
  95
  96                 /* polling HSync */
  97                 corgi_ts->machinfo->wait_hsync();
  98                 /* get CCNT */
  99                 CCNT(timer1);
 100         }
 101
 102         if (doRecive)
 103                 pos = corgi_ssp_ads7846_get();
 104
 105         if (doSend) {
 106                 int cmd = ADSCTRL_PD0 | ADSCTRL_PD1 | (address << ADSCTRL_ADR_SH) | ADSCTRL_STS;
 107                 /* dummy command */
 108                 corgi_ssp_ads7846_put(cmd);
 109                 corgi_ssp_ads7846_get();
 110
 111                 if (wait_time) {
 112                         /* Wait after HSync */
 113                         CCNT(timer2);
 114                         if (timer2-timer1 > wait_time) {
 115                                 /* too slow - timeout, try again */
 116                                 corgi_ts->machinfo->wait_hsync();
 117                                 /* get OSCR */
 118                                 CCNT(timer1);
 119                                 /* Wait after HSync */
 120                                 CCNT(timer2);
 121                         }
 122                         while (timer2 - timer1 < wait_time)
 123                                 CCNT(timer2);
 124                 }
 125                 corgi_ssp_ads7846_put(cmd);
 126                 if (wait_time && !(pmnc & 0x01))
 127                         PMNC_SET(pmnc);
 128         }
 129         return pos;
 130 }
 131
 132 static int read_xydata(struct corgi_ts *corgi_ts)
 133 {
 134         unsigned int x, y, z1, z2;
 135         unsigned long flags, wait_time;
 136
 137         /* critical section */
 138         local_irq_save(flags);
 139         corgi_ssp_ads7846_lock();
 140         wait_time = calc_waittime(corgi_ts);
 141
 142         /* Y-axis */
 143         sync_receive_data_send_cmd(corgi_ts, 0, 1, 1u, wait_time);
 144
 145         /* Y-axis */
 146         sync_receive_data_send_cmd(corgi_ts, 1, 1, 1u, wait_time);
 147
 148         /* X-axis */
 149         y = sync_receive_data_send_cmd(corgi_ts, 1, 1, 5u, wait_time);
 150
 151         /* Z1 */
 152         x = sync_receive_data_send_cmd(corgi_ts, 1, 1, 3u, wait_time);
 153
 154         /* Z2 */
 155         z1 = sync_receive_data_send_cmd(corgi_ts, 1, 1, 4u, wait_time);
 156         z2 = sync_receive_data_send_cmd(corgi_ts, 1, 0, 4u, wait_time);
 157
 158         /* Power-Down Enable */
 159         corgi_ssp_ads7846_put((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 160         corgi_ssp_ads7846_get();
 161
 162         corgi_ssp_ads7846_unlock();
 163         local_irq_restore(flags);
 164
 165         if (x== 0 || y == 0 || z1 == 0 || (x * (z2 - z1) / z1) >= 15000) {
 166                 corgi_ts->tc.pressure = 0;
 167                 return 0;
 168         }
 169
 170         corgi_ts->tc.x = x;
 171         corgi_ts->tc.y = y;
 172         corgi_ts->tc.pressure = (x * (z2 - z1)) / z1;
 173         return 1;
 174 }
 175
 176 static void new_data(struct corgi_ts *corgi_ts)
 177 {
 178         if (corgi_ts->power_mode != PWR_MODE_ACTIVE)
 179                 return;
 180
 181         if (!corgi_ts->tc.pressure && corgi_ts->pendown == 0)
 182                 return;
 183
 184         input_report_abs(corgi_ts->input, ABS_X, corgi_ts->tc.x);
 185         input_report_abs(corgi_ts->input, ABS_Y, corgi_ts->tc.y);
 186         input_report_abs(corgi_ts->input, ABS_PRESSURE, corgi_ts->tc.pressure);
 187         input_report_key(corgi_ts->input, BTN_TOUCH, (corgi_ts->pendown != 0));
 188         input_sync(corgi_ts->input);
 189 }
 190
 191 static void ts_interrupt_main(struct corgi_ts *corgi_ts, int isTimer)
 192 {
 193         if ((GPLR(IRQ_TO_GPIO(corgi_ts->irq_gpio)) & GPIO_bit(IRQ_TO_GPIO(corgi_ts->irq_gpio))) == 0) {
 194                 /* Disable Interrupt */
 195                 set_irq_type(corgi_ts->irq_gpio, IRQT_NOEDGE);
 196                 if (read_xydata(corgi_ts)) {
 197                         corgi_ts->pendown = 1;
 198                         new_data(corgi_ts);
 199                 }
 200                 mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
 201         } else {
 202                 if (corgi_ts->pendown == 1 || corgi_ts->pendown == 2) {
 203                         mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
 204                         corgi_ts->pendown++;
 205                         return;
 206                 }
 207
 208                 if (corgi_ts->pendown) {
 209                         corgi_ts->tc.pressure = 0;
 210                         new_data(corgi_ts);
 211                 }
 212
 213                 /* Enable Falling Edge */
 214                 set_irq_type(corgi_ts->irq_gpio, IRQT_FALLING);
 215                 corgi_ts->pendown = 0;
 216         }
 217 }
 218
 219 static void corgi_ts_timer(unsigned long data)
 220 {
 221         struct corgi_ts *corgits_data = (struct corgi_ts *) data;
 222         ts_interrupt_main(corgits_data, 1, NULL);
 223 }
 224
 225 static irqreturn_t ts_interrupt(int irq, void *dev_id)
 226 {
 227         struct corgi_ts *corgits_data = dev_id;
 228         ts_interrupt_main(corgits_data, 0);
 229         return IRQ_HANDLED;
 230 }
 231
 232 #ifdef CONFIG_PM
 233 static int corgits_suspend(struct platform_device *dev, pm_message_t state)
 234 {
 235         struct corgi_ts *corgi_ts = platform_get_drvdata(dev);
 236
 237         if (corgi_ts->pendown) {
 238                 del_timer_sync(&corgi_ts->timer);
 239                 corgi_ts->tc.pressure = 0;
 240                 new_data(corgi_ts, NULL);
 241                 corgi_ts->pendown = 0;
 242         }
 243         corgi_ts->power_mode = PWR_MODE_SUSPEND;
 244
 245         corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 246
 247         return 0;
 248 }
 249
 250 static int corgits_resume(struct platform_device *dev)
 251 {
 252         struct corgi_ts *corgi_ts = platform_get_drvdata(dev);
 253
 254         corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 255         /* Enable Falling Edge */
 256         set_irq_type(corgi_ts->irq_gpio, IRQT_FALLING);
 257         corgi_ts->power_mode = PWR_MODE_ACTIVE;
 258
 259         return 0;
 260 }
 261 #else
 262 #define corgits_suspend         NULL
 263 #define corgits_resume          NULL
 264 #endif
 265
 266 static int __init corgits_probe(struct platform_device *pdev)
 267 {
 268         struct corgi_ts *corgi_ts;
 269         struct input_dev *input_dev;
 270         int err = -ENOMEM;
 271
 272         corgi_ts = kzalloc(sizeof(struct corgi_ts), GFP_KERNEL);
 273         input_dev = input_allocate_device();
 274         if (!corgi_ts || !input_dev)
 275                 goto fail;
 276
 277         platform_set_drvdata(pdev, corgi_ts);
 278
 279         corgi_ts->machinfo = pdev->dev.platform_data;
 280         corgi_ts->irq_gpio = platform_get_irq(pdev, 0);
 281
 282         if (corgi_ts->irq_gpio < 0) {
 283                 err = -ENODEV;
 284                 goto fail;
 285         }
 286
 287         corgi_ts->input = input_dev;
 288
 289         init_timer(&corgi_ts->timer);
 290         corgi_ts->timer.data = (unsigned long) corgi_ts;
 291         corgi_ts->timer.function = corgi_ts_timer;
 292
 293         input_dev->name = "Corgi Touchscreen";
 294         input_dev->phys = "corgits/input0";
 295         input_dev->id.bustype = BUS_HOST;
 296         input_dev->id.vendor = 0x0001;
 297         input_dev->id.product = 0x0002;
 298         input_dev->id.version = 0x0100;
 299         input_dev->cdev.dev = &pdev->dev;
 300         input_dev->private = corgi_ts;
 301
 302         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 303         input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
 304         input_set_abs_params(input_dev, ABS_X, X_AXIS_MIN, X_AXIS_MAX, 0, 0);
 305         input_set_abs_params(input_dev, ABS_Y, Y_AXIS_MIN, Y_AXIS_MAX, 0, 0);
 306         input_set_abs_params(input_dev, ABS_PRESSURE, PRESSURE_MIN, PRESSURE_MAX, 0, 0);
 307
 308         pxa_gpio_mode(IRQ_TO_GPIO(corgi_ts->irq_gpio) | GPIO_IN);
 309
 310         /* Initiaize ADS7846 Difference Reference mode */
 311         corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 312         mdelay(5);
 313         corgi_ssp_ads7846_putget((3u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 314         mdelay(5);
 315         corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 316         mdelay(5);
 317         corgi_ssp_ads7846_putget((5u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 318         mdelay(5);
 319
 320         if (request_irq(corgi_ts->irq_gpio, ts_interrupt, IRQF_DISABLED, "ts", corgi_ts)) {
 321                 err = -EBUSY;
 322                 goto fail;
 323         }
 324
 325         input_register_device(corgi_ts->input);
 326
 327         corgi_ts->power_mode = PWR_MODE_ACTIVE;
 328
 329         /* Enable Falling Edge */
 330         set_irq_type(corgi_ts->irq_gpio, IRQT_FALLING);
 331
 332         return 0;
 333
 334  fail:  input_free_device(input_dev);
 335         kfree(corgi_ts);
 336         return err;
 337
 338 }
 339
 340 static int corgits_remove(struct platform_device *pdev)
 341 {
 342         struct corgi_ts *corgi_ts = platform_get_drvdata(pdev);
 343
 344         free_irq(corgi_ts->irq_gpio, NULL);
 345         del_timer_sync(&corgi_ts->timer);
 346         corgi_ts->machinfo->put_hsync();
 347         input_unregister_device(corgi_ts->input);
 348         kfree(corgi_ts);
 349         return 0;
 350 }
 351
 352 static struct platform_driver corgits_driver = {
 353         .probe          = corgits_probe,
 354         .remove         = corgits_remove,
 355         .suspend        = corgits_suspend,
 356         .resume         = corgits_resume,
 357         .driver         = {
 358                 .name   = "corgi-ts",
 359         },
 360 };
 361
 362 static int __devinit corgits_init(void)
 363 {
 364         return platform_driver_register(&corgits_driver);
 365 }
 366
 367 static void __exit corgits_exit(void)
 368 {
 369         platform_driver_unregister(&corgits_driver);
 370 }
 371
 372 module_init(corgits_init);
 373 module_exit(corgits_exit);
 374
 375 MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
 376 MODULE_DESCRIPTION("Corgi TouchScreen Driver");
 377 MODULE_LICENSE("GPL");