linux/drivers/input/touchscreen/corgi_ts.c
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   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 <mach/sharpsl.h>
  23#include <mach/hardware.h>
  24#include <mach/pxa2xx-gpio.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
  37struct ts_event {
  38        short pressure;
  39        short x;
  40        short y;
  41};
  42
  43struct 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 */
  73extern unsigned int get_clk_frequency_khz(int info);
  74
  75static unsigned long calc_waittime(struct corgi_ts *corgi_ts)
  76{
  77        unsigned long hsync_invperiod = corgi_ts->machinfo->get_hsync_invperiod();
  78
  79        if (hsync_invperiod)
  80                return get_clk_frequency_khz(0)*1000/hsync_invperiod;
  81        else
  82                return 0;
  83}
  84
  85static 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 CCNT */
 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
 132static 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
 176static void new_data(struct corgi_ts *corgi_ts)
 177{
 178        struct input_dev *dev = corgi_ts->input;
 179
 180        if (corgi_ts->power_mode != PWR_MODE_ACTIVE)
 181                return;
 182
 183        if (!corgi_ts->tc.pressure && corgi_ts->pendown == 0)
 184                return;
 185
 186        input_report_abs(dev, ABS_X, corgi_ts->tc.x);
 187        input_report_abs(dev, ABS_Y, corgi_ts->tc.y);
 188        input_report_abs(dev, ABS_PRESSURE, corgi_ts->tc.pressure);
 189        input_report_key(dev, BTN_TOUCH, corgi_ts->pendown);
 190        input_sync(dev);
 191}
 192
 193static void ts_interrupt_main(struct corgi_ts *corgi_ts, int isTimer)
 194{
 195        if ((GPLR(IRQ_TO_GPIO(corgi_ts->irq_gpio)) & GPIO_bit(IRQ_TO_GPIO(corgi_ts->irq_gpio))) == 0) {
 196                /* Disable Interrupt */
 197                set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_NONE);
 198                if (read_xydata(corgi_ts)) {
 199                        corgi_ts->pendown = 1;
 200                        new_data(corgi_ts);
 201                }
 202                mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
 203        } else {
 204                if (corgi_ts->pendown == 1 || corgi_ts->pendown == 2) {
 205                        mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
 206                        corgi_ts->pendown++;
 207                        return;
 208                }
 209
 210                if (corgi_ts->pendown) {
 211                        corgi_ts->tc.pressure = 0;
 212                        new_data(corgi_ts);
 213                }
 214
 215                /* Enable Falling Edge */
 216                set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_EDGE_FALLING);
 217                corgi_ts->pendown = 0;
 218        }
 219}
 220
 221static void corgi_ts_timer(unsigned long data)
 222{
 223        struct corgi_ts *corgits_data = (struct corgi_ts *) data;
 224
 225        ts_interrupt_main(corgits_data, 1);
 226}
 227
 228static irqreturn_t ts_interrupt(int irq, void *dev_id)
 229{
 230        struct corgi_ts *corgits_data = dev_id;
 231
 232        ts_interrupt_main(corgits_data, 0);
 233        return IRQ_HANDLED;
 234}
 235
 236#ifdef CONFIG_PM
 237static int corgits_suspend(struct platform_device *dev, pm_message_t state)
 238{
 239        struct corgi_ts *corgi_ts = platform_get_drvdata(dev);
 240
 241        if (corgi_ts->pendown) {
 242                del_timer_sync(&corgi_ts->timer);
 243                corgi_ts->tc.pressure = 0;
 244                new_data(corgi_ts);
 245                corgi_ts->pendown = 0;
 246        }
 247        corgi_ts->power_mode = PWR_MODE_SUSPEND;
 248
 249        corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 250
 251        return 0;
 252}
 253
 254static int corgits_resume(struct platform_device *dev)
 255{
 256        struct corgi_ts *corgi_ts = platform_get_drvdata(dev);
 257
 258        corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 259        /* Enable Falling Edge */
 260        set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_EDGE_FALLING);
 261        corgi_ts->power_mode = PWR_MODE_ACTIVE;
 262
 263        return 0;
 264}
 265#else
 266#define corgits_suspend         NULL
 267#define corgits_resume          NULL
 268#endif
 269
 270static int __devinit corgits_probe(struct platform_device *pdev)
 271{
 272        struct corgi_ts *corgi_ts;
 273        struct input_dev *input_dev;
 274        int err = -ENOMEM;
 275
 276        corgi_ts = kzalloc(sizeof(struct corgi_ts), GFP_KERNEL);
 277        input_dev = input_allocate_device();
 278        if (!corgi_ts || !input_dev)
 279                goto fail1;
 280
 281        platform_set_drvdata(pdev, corgi_ts);
 282
 283        corgi_ts->machinfo = pdev->dev.platform_data;
 284        corgi_ts->irq_gpio = platform_get_irq(pdev, 0);
 285
 286        if (corgi_ts->irq_gpio < 0) {
 287                err = -ENODEV;
 288                goto fail1;
 289        }
 290
 291        corgi_ts->input = input_dev;
 292
 293        init_timer(&corgi_ts->timer);
 294        corgi_ts->timer.data = (unsigned long) corgi_ts;
 295        corgi_ts->timer.function = corgi_ts_timer;
 296
 297        input_dev->name = "Corgi Touchscreen";
 298        input_dev->phys = "corgits/input0";
 299        input_dev->id.bustype = BUS_HOST;
 300        input_dev->id.vendor = 0x0001;
 301        input_dev->id.product = 0x0002;
 302        input_dev->id.version = 0x0100;
 303        input_dev->dev.parent = &pdev->dev;
 304
 305        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 306        input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 307        input_set_abs_params(input_dev, ABS_X, X_AXIS_MIN, X_AXIS_MAX, 0, 0);
 308        input_set_abs_params(input_dev, ABS_Y, Y_AXIS_MIN, Y_AXIS_MAX, 0, 0);
 309        input_set_abs_params(input_dev, ABS_PRESSURE, PRESSURE_MIN, PRESSURE_MAX, 0, 0);
 310
 311        pxa_gpio_mode(IRQ_TO_GPIO(corgi_ts->irq_gpio) | GPIO_IN);
 312
 313        /* Initiaize ADS7846 Difference Reference mode */
 314        corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 315        mdelay(5);
 316        corgi_ssp_ads7846_putget((3u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 317        mdelay(5);
 318        corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 319        mdelay(5);
 320        corgi_ssp_ads7846_putget((5u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
 321        mdelay(5);
 322
 323        if (request_irq(corgi_ts->irq_gpio, ts_interrupt, IRQF_DISABLED, "ts", corgi_ts)) {
 324                err = -EBUSY;
 325                goto fail1;
 326        }
 327
 328        err = input_register_device(corgi_ts->input);
 329        if (err)
 330                goto fail2;
 331
 332        corgi_ts->power_mode = PWR_MODE_ACTIVE;
 333
 334        /* Enable Falling Edge */
 335        set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_EDGE_FALLING);
 336
 337        return 0;
 338
 339 fail2: free_irq(corgi_ts->irq_gpio, corgi_ts);
 340 fail1: input_free_device(input_dev);
 341        kfree(corgi_ts);
 342        return err;
 343}
 344
 345static int __devexit corgits_remove(struct platform_device *pdev)
 346{
 347        struct corgi_ts *corgi_ts = platform_get_drvdata(pdev);
 348
 349        free_irq(corgi_ts->irq_gpio, corgi_ts);
 350        del_timer_sync(&corgi_ts->timer);
 351        corgi_ts->machinfo->put_hsync();
 352        input_unregister_device(corgi_ts->input);
 353        kfree(corgi_ts);
 354
 355        return 0;
 356}
 357
 358static struct platform_driver corgits_driver = {
 359        .probe          = corgits_probe,
 360        .remove         = __devexit_p(corgits_remove),
 361        .suspend        = corgits_suspend,
 362        .resume         = corgits_resume,
 363        .driver         = {
 364                .name   = "corgi-ts",
 365                .owner  = THIS_MODULE,
 366        },
 367};
 368
 369static int __init corgits_init(void)
 370{
 371        return platform_driver_register(&corgits_driver);
 372}
 373
 374static void __exit corgits_exit(void)
 375{
 376        platform_driver_unregister(&corgits_driver);
 377}
 378
 379module_init(corgits_init);
 380module_exit(corgits_exit);
 381
 382MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
 383MODULE_DESCRIPTION("Corgi TouchScreen Driver");
 384MODULE_LICENSE("GPL");
 385MODULE_ALIAS("platform:corgi-ts");
 386