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 <asm/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, struct pt_regs *regs)
 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_regs(corgi_ts->input, regs);
 185         input_report_abs(corgi_ts->input, ABS_X, corgi_ts->tc.x);
 186         input_report_abs(corgi_ts->input, ABS_Y, corgi_ts->tc.y);
 187         input_report_abs(corgi_ts->input, ABS_PRESSURE, corgi_ts->tc.pressure);
 188         input_report_key(corgi_ts->input, BTN_TOUCH, (corgi_ts->pendown != 0));
 189         input_sync(corgi_ts->input);
 190 }
 191
 192 static void ts_interrupt_main(struct corgi_ts *corgi_ts, int isTimer, struct pt_regs *regs)
 193 {
 194         if ((GPLR(IRQ_TO_GPIO(corgi_ts->irq_gpio)) & GPIO_bit(IRQ_TO_GPIO(corgi_ts->irq_gpio))) == 0) {
 195                 /* Disable Interrupt */
 196                 set_irq_type(corgi_ts->irq_gpio, IRQT_NOEDGE);
 197                 if (read_xydata(corgi_ts)) {
 198                         corgi_ts->pendown = 1;
 199                         new_data(corgi_ts, regs);
 200                 }
 201                 mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
 202         } else {
 203                 if (corgi_ts->pendown == 1 || corgi_ts->pendown == 2) {
 204                         mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
 205                         corgi_ts->pendown++;
 206                         return;
 207                 }
 208
 209                 if (corgi_ts->pendown) {
 210                         corgi_ts->tc.pressure = 0;
 211                         new_data(corgi_ts, regs);
 212                 }
 213
 214                 /* Enable Falling Edge */
 215                 set_irq_type(corgi_ts->irq_gpio, IRQT_FALLING);
 216                 corgi_ts->pendown = 0;
 217         }
 218 }
 219
 220 static void corgi_ts_timer(unsigned long data)
 221 {
 222         struct corgi_ts *corgits_data = (struct corgi_ts *) data;
 223         ts_interrupt_main(corgits_data, 1, NULL);
 224 }
 225
 226 static irqreturn_t ts_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 227 {
 228         struct corgi_ts *corgits_data = dev_id;
 229         ts_interrupt_main(corgits_data, 0, regs);
 230         return IRQ_HANDLED;
 231 }
 232
 233 #ifdef CONFIG_PM
 234 static int corgits_suspend(struct device *dev, pm_message_t state)
 235 {
 236         struct corgi_ts *corgi_ts = dev_get_drvdata(dev);
 237
 238         if (corgi_ts->pendown) {
 239                 del_timer_sync(&corgi_ts->timer);
 240                 corgi_ts->tc.pressure = 0;
 241                 new_data(corgi_ts, NULL);
 242                 corgi_ts->pendown = 0;
 243         }
 244         corgi_ts->power_mode = PWR_MODE_SUSPEND;
 245
 246         corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 247
 248         return 0;
 249 }
 250
 251 static int corgits_resume(struct device *dev)
 252 {
 253         struct corgi_ts *corgi_ts = dev_get_drvdata(dev);
 254
 255         corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 256         /* Enable Falling Edge */
 257         set_irq_type(corgi_ts->irq_gpio, IRQT_FALLING);
 258         corgi_ts->power_mode = PWR_MODE_ACTIVE;
 259
 260         return 0;
 261 }
 262 #else
 263 #define corgits_suspend         NULL
 264 #define corgits_resume          NULL
 265 #endif
 266
 267 static int __init corgits_probe(struct device *dev)
 268 {
 269         struct corgi_ts *corgi_ts;
 270         struct platform_device *pdev = to_platform_device(dev);
 271         struct input_dev *input_dev;
 272         int err = -ENOMEM;
 273
 274         corgi_ts = kzalloc(sizeof(struct corgi_ts), GFP_KERNEL);
 275         input_dev = input_allocate_device();
 276         if (!corgi_ts || !input_dev)
 277                 goto fail;
 278
 279         dev_set_drvdata(dev, corgi_ts);
 280
 281         corgi_ts->machinfo = dev->platform_data;
 282         corgi_ts->irq_gpio = platform_get_irq(pdev, 0);
 283
 284         if (corgi_ts->irq_gpio < 0) {
 285                 err = -ENODEV;
 286                 goto fail;
 287         }
 288
 289         corgi_ts->input = input_dev;
 290
 291         init_timer(&corgi_ts->timer);
 292         corgi_ts->timer.data = (unsigned long) corgi_ts;
 293         corgi_ts->timer.function = corgi_ts_timer;
 294
 295         input_dev->name = "Corgi Touchscreen";
 296         input_dev->phys = "corgits/input0";
 297         input_dev->id.bustype = BUS_HOST;
 298         input_dev->id.vendor = 0x0001;
 299         input_dev->id.product = 0x0002;
 300         input_dev->id.version = 0x0100;
 301         input_dev->cdev.dev = dev;
 302         input_dev->private = corgi_ts;
 303
 304         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 305         input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
 306         input_set_abs_params(input_dev, ABS_X, X_AXIS_MIN, X_AXIS_MAX, 0, 0);
 307         input_set_abs_params(input_dev, ABS_Y, Y_AXIS_MIN, Y_AXIS_MAX, 0, 0);
 308         input_set_abs_params(input_dev, ABS_PRESSURE, PRESSURE_MIN, PRESSURE_MAX, 0, 0);
 309
 310         pxa_gpio_mode(IRQ_TO_GPIO(corgi_ts->irq_gpio) | GPIO_IN);
 311
 312         /* Initiaize ADS7846 Difference Reference mode */
 313         corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 314         mdelay(5);
 315         corgi_ssp_ads7846_putget((3u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 316         mdelay(5);
 317         corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 318         mdelay(5);
 319         corgi_ssp_ads7846_putget((5u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 320         mdelay(5);
 321
 322         if (request_irq(corgi_ts->irq_gpio, ts_interrupt, SA_INTERRUPT, "ts", corgi_ts)) {
 323                 err = -EBUSY;
 324                 goto fail;
 325         }
 326
 327         input_register_device(corgi_ts->input);
 328
 329         corgi_ts->power_mode = PWR_MODE_ACTIVE;
 330
 331         /* Enable Falling Edge */
 332         set_irq_type(corgi_ts->irq_gpio, IRQT_FALLING);
 333
 334         return 0;
 335
 336  fail:  input_free_device(input_dev);
 337         kfree(corgi_ts);
 338         return err;
 339
 340 }
 341
 342 static int corgits_remove(struct device *dev)
 343 {
 344         struct corgi_ts *corgi_ts = dev_get_drvdata(dev);
 345
 346         free_irq(corgi_ts->irq_gpio, NULL);
 347         del_timer_sync(&corgi_ts->timer);
 348         corgi_ts->machinfo->put_hsync();
 349         input_unregister_device(corgi_ts->input);
 350         kfree(corgi_ts);
 351         return 0;
 352 }
 353
 354 static struct device_driver corgits_driver = {
 355         .name           = "corgi-ts",
 356         .bus            = &platform_bus_type,
 357         .probe          = corgits_probe,
 358         .remove         = corgits_remove,
 359         .suspend        = corgits_suspend,
 360         .resume         = corgits_resume,
 361 };
 362
 363 static int __devinit corgits_init(void)
 364 {
 365         return driver_register(&corgits_driver);
 366 }
 367
 368 static void __exit corgits_exit(void)
 369 {
 370         driver_unregister(&corgits_driver);
 371 }
 372
 373 module_init(corgits_init);
 374 module_exit(corgits_exit);
 375
 376 MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
 377 MODULE_DESCRIPTION("Corgi TouchScreen Driver");
 378 MODULE_LICENSE("GPL");