drivers/input/touchscreen/w90p910_ts.c

   1 /*
   2  * Copyright (c) 2008 Nuvoton technology corporation.
   3  *
   4  * Wan ZongShun <mcuos.com@gmail.com>
   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 as published by
   8  * the Free Software Foundation;version 2 of the License.
   9  *
  10  */
  11
  12 #include <linux/delay.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/io.h>
  16 #include <linux/input.h>
  17 #include <linux/interrupt.h>
  18
  19 /* ADC controller bit defines */
  20 #define ADC_DELAY       0xf00
  21 #define ADC_DOWN        0x01
  22 #define ADC_TSC_Y       (0x01 << 8)
  23 #define ADC_TSC_X       (0x00 << 8)
  24 #define TSC_FOURWIRE    (~(0x03 << 1))
  25 #define ADC_CLK_EN      (0x01 << 28)    /* ADC clock enable */
  26 #define ADC_READ_CON    (0x01 << 12)
  27 #define ADC_CONV        (0x01 << 13)
  28 #define ADC_SEMIAUTO    (0x01 << 14)
  29 #define ADC_WAITTRIG    (0x03 << 14)
  30 #define ADC_RST1        (0x01 << 16)
  31 #define ADC_RST0        (0x00 << 16)
  32 #define ADC_EN          (0x01 << 17)
  33 #define ADC_INT         (0x01 << 18)
  34 #define WT_INT          (0x01 << 20)
  35 #define ADC_INT_EN      (0x01 << 21)
  36 #define LVD_INT_EN      (0x01 << 22)
  37 #define WT_INT_EN       (0x01 << 23)
  38 #define ADC_DIV         (0x04 << 1)     /* div = 6 */
  39
  40 enum ts_state {
  41         TS_WAIT_NEW_PACKET,     /* We are waiting next touch report */
  42         TS_WAIT_X_COORD,        /* We are waiting for ADC to report X coord */
  43         TS_WAIT_Y_COORD,        /* We are waiting for ADC to report Y coord */
  44         TS_IDLE,                /* Input device is closed, don't do anything */
  45 };
  46
  47 struct w90p910_ts {
  48         struct input_dev *input;
  49         struct timer_list timer;
  50         int irq_num;
  51         void __iomem *clocken;
  52         void __iomem *ts_reg;
  53         spinlock_t lock;
  54         enum ts_state state;
  55 };
  56
  57 static void w90p910_report_event(struct w90p910_ts *w90p910_ts, bool down)
  58 {
  59         struct input_dev *dev = w90p910_ts->input;
  60
  61         if (down) {
  62                 input_report_abs(dev, ABS_X,
  63                                  __raw_readl(w90p910_ts->ts_reg + 0x0c));
  64                 input_report_abs(dev, ABS_Y,
  65                                  __raw_readl(w90p910_ts->ts_reg + 0x10));
  66         }
  67
  68         input_report_key(dev, BTN_TOUCH, down);
  69         input_sync(dev);
  70 }
  71
  72 static void w90p910_prepare_x_reading(struct w90p910_ts *w90p910_ts)
  73 {
  74         unsigned long ctlreg;
  75
  76         __raw_writel(ADC_TSC_X, w90p910_ts->ts_reg + 0x04);
  77         ctlreg = __raw_readl(w90p910_ts->ts_reg);
  78         ctlreg &= ~(ADC_WAITTRIG | WT_INT | WT_INT_EN);
  79         ctlreg |= ADC_SEMIAUTO | ADC_INT_EN | ADC_CONV;
  80         __raw_writel(ctlreg, w90p910_ts->ts_reg);
  81
  82         w90p910_ts->state = TS_WAIT_X_COORD;
  83 }
  84
  85 static void w90p910_prepare_y_reading(struct w90p910_ts *w90p910_ts)
  86 {
  87         unsigned long ctlreg;
  88
  89         __raw_writel(ADC_TSC_Y, w90p910_ts->ts_reg + 0x04);
  90         ctlreg = __raw_readl(w90p910_ts->ts_reg);
  91         ctlreg &= ~(ADC_WAITTRIG | ADC_INT | WT_INT_EN);
  92         ctlreg |= ADC_SEMIAUTO | ADC_INT_EN | ADC_CONV;
  93         __raw_writel(ctlreg, w90p910_ts->ts_reg);
  94
  95         w90p910_ts->state = TS_WAIT_Y_COORD;
  96 }
  97
  98 static void w90p910_prepare_next_packet(struct w90p910_ts *w90p910_ts)
  99 {
 100         unsigned long ctlreg;
 101
 102         ctlreg = __raw_readl(w90p910_ts->ts_reg);
 103         ctlreg &= ~(ADC_INT | ADC_INT_EN | ADC_SEMIAUTO | ADC_CONV);
 104         ctlreg |= ADC_WAITTRIG | WT_INT_EN;
 105         __raw_writel(ctlreg, w90p910_ts->ts_reg);
 106
 107         w90p910_ts->state = TS_WAIT_NEW_PACKET;
 108 }
 109
 110 static irqreturn_t w90p910_ts_interrupt(int irq, void *dev_id)
 111 {
 112         struct w90p910_ts *w90p910_ts = dev_id;
 113         unsigned long flags;
 114
 115         spin_lock_irqsave(&w90p910_ts->lock, flags);
 116
 117         switch (w90p910_ts->state) {
 118         case TS_WAIT_NEW_PACKET:
 119                 /*
 120                  * The controller only generates interrupts when pen
 121                  * is down.
 122                  */
 123                 del_timer(&w90p910_ts->timer);
 124                 w90p910_prepare_x_reading(w90p910_ts);
 125                 break;
 126
 127
 128         case TS_WAIT_X_COORD:
 129                 w90p910_prepare_y_reading(w90p910_ts);
 130                 break;
 131
 132         case TS_WAIT_Y_COORD:
 133                 w90p910_report_event(w90p910_ts, true);
 134                 w90p910_prepare_next_packet(w90p910_ts);
 135                 mod_timer(&w90p910_ts->timer, jiffies + msecs_to_jiffies(100));
 136                 break;
 137
 138         case TS_IDLE:
 139                 break;
 140         }
 141
 142         spin_unlock_irqrestore(&w90p910_ts->lock, flags);
 143
 144         return IRQ_HANDLED;
 145 }
 146
 147 static void w90p910_check_pen_up(unsigned long data)
 148 {
 149         struct w90p910_ts *w90p910_ts = (struct w90p910_ts *) data;
 150         unsigned long flags;
 151
 152         spin_lock_irqsave(&w90p910_ts->lock, flags);
 153
 154         if (w90p910_ts->state == TS_WAIT_NEW_PACKET &&
 155             !(__raw_readl(w90p910_ts->ts_reg + 0x04) & ADC_DOWN)) {
 156
 157                 w90p910_report_event(w90p910_ts, false);
 158         }
 159
 160         spin_unlock_irqrestore(&w90p910_ts->lock, flags);
 161 }
 162
 163 static int w90p910_open(struct input_dev *dev)
 164 {
 165         struct w90p910_ts *w90p910_ts = input_get_drvdata(dev);
 166         unsigned long val;
 167
 168         /* enable the ADC clock */
 169         val = __raw_readl(w90p910_ts->clocken);
 170         __raw_writel(val | ADC_CLK_EN, w90p910_ts->clocken);
 171
 172         __raw_writel(ADC_RST1, w90p910_ts->ts_reg);
 173         msleep(1);
 174         __raw_writel(ADC_RST0, w90p910_ts->ts_reg);
 175         msleep(1);
 176
 177         /* set delay and screen type */
 178         val = __raw_readl(w90p910_ts->ts_reg + 0x04);
 179         __raw_writel(val & TSC_FOURWIRE, w90p910_ts->ts_reg + 0x04);
 180         __raw_writel(ADC_DELAY, w90p910_ts->ts_reg + 0x08);
 181
 182         w90p910_ts->state = TS_WAIT_NEW_PACKET;
 183         wmb();
 184
 185         /* set trigger mode */
 186         val = __raw_readl(w90p910_ts->ts_reg);
 187         val |= ADC_WAITTRIG | ADC_DIV | ADC_EN | WT_INT_EN;
 188         __raw_writel(val, w90p910_ts->ts_reg);
 189
 190         return 0;
 191 }
 192
 193 static void w90p910_close(struct input_dev *dev)
 194 {
 195         struct w90p910_ts *w90p910_ts = input_get_drvdata(dev);
 196         unsigned long val;
 197
 198         /* disable trigger mode */
 199
 200         spin_lock_irq(&w90p910_ts->lock);
 201
 202         w90p910_ts->state = TS_IDLE;
 203
 204         val = __raw_readl(w90p910_ts->ts_reg);
 205         val &= ~(ADC_WAITTRIG | ADC_DIV | ADC_EN | WT_INT_EN | ADC_INT_EN);
 206         __raw_writel(val, w90p910_ts->ts_reg);
 207
 208         spin_unlock_irq(&w90p910_ts->lock);
 209
 210         /* Now that interrupts are shut off we can safely delete timer */
 211         del_timer_sync(&w90p910_ts->timer);
 212
 213         /* stop the ADC clock */
 214         val = __raw_readl(w90p910_ts->clocken);
 215         __raw_writel(val & ~ADC_CLK_EN, w90p910_ts->clocken);
 216 }
 217
 218 static int __devinit w90x900ts_probe(struct platform_device *pdev)
 219 {
 220         struct w90p910_ts *w90p910_ts;
 221         struct input_dev *input_dev;
 222         struct resource *res;
 223         int err;
 224
 225         w90p910_ts = kzalloc(sizeof(struct w90p910_ts), GFP_KERNEL);
 226         input_dev = input_allocate_device();
 227         if (!w90p910_ts || !input_dev) {
 228                 err = -ENOMEM;
 229                 goto fail1;
 230         }
 231
 232         w90p910_ts->input = input_dev;
 233         w90p910_ts->state = TS_IDLE;
 234         spin_lock_init(&w90p910_ts->lock);
 235         setup_timer(&w90p910_ts->timer, w90p910_check_pen_up,
 236                     (unsigned long)&w90p910_ts);
 237
 238         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 239         if (!res) {
 240                 err = -ENXIO;
 241                 goto fail1;
 242         }
 243
 244         if (!request_mem_region(res->start, res->end - res->start + 1,
 245                                 pdev->name)) {
 246                 err = -EBUSY;
 247                 goto fail1;
 248         }
 249
 250         w90p910_ts->ts_reg = ioremap(res->start, res->end - res->start + 1);
 251         if (!w90p910_ts->ts_reg) {
 252                 err = -ENOMEM;
 253                 goto fail2;
 254         }
 255
 256         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 257         if (!res) {
 258                 err = -ENXIO;
 259                 goto fail3;
 260         }
 261
 262         w90p910_ts->clocken = (void __iomem *)res->start;
 263
 264         input_dev->name = "W90P910 TouchScreen";
 265         input_dev->phys = "w90p910ts/event0";
 266         input_dev->id.bustype = BUS_HOST;
 267         input_dev->id.vendor  = 0x0005;
 268         input_dev->id.product = 0x0001;
 269         input_dev->id.version = 0x0100;
 270         input_dev->dev.parent = &pdev->dev;
 271         input_dev->open = w90p910_open;
 272         input_dev->close = w90p910_close;
 273
 274         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 275         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 276
 277         input_set_abs_params(input_dev, ABS_X, 0, 0x400, 0, 0);
 278         input_set_abs_params(input_dev, ABS_Y, 0, 0x400, 0, 0);
 279
 280         input_set_drvdata(input_dev, w90p910_ts);
 281
 282         w90p910_ts->irq_num = platform_get_irq(pdev, 0);
 283         if (request_irq(w90p910_ts->irq_num, w90p910_ts_interrupt,
 284                         IRQF_DISABLED, "w90p910ts", w90p910_ts)) {
 285                 err = -EBUSY;
 286                 goto fail3;
 287         }
 288
 289         err = input_register_device(w90p910_ts->input);
 290         if (err)
 291                 goto fail4;
 292
 293         platform_set_drvdata(pdev, w90p910_ts);
 294
 295         return 0;
 296
 297 fail4:  free_irq(w90p910_ts->irq_num, w90p910_ts);
 298 fail3:  iounmap(w90p910_ts->ts_reg);
 299 fail2:  release_mem_region(res->start, res->end - res->start + 1);
 300 fail1:  input_free_device(input_dev);
 301         kfree(w90p910_ts);
 302         return err;
 303 }
 304
 305 static int __devexit w90x900ts_remove(struct platform_device *pdev)
 306 {
 307         struct w90p910_ts *w90p910_ts = platform_get_drvdata(pdev);
 308         struct resource *res;
 309
 310         free_irq(w90p910_ts->irq_num, w90p910_ts);
 311         del_timer_sync(&w90p910_ts->timer);
 312         iounmap(w90p910_ts->ts_reg);
 313
 314         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 315         release_mem_region(res->start, res->end - res->start + 1);
 316
 317         input_unregister_device(w90p910_ts->input);
 318         kfree(w90p910_ts);
 319
 320         platform_set_drvdata(pdev, NULL);
 321
 322         return 0;
 323 }
 324
 325 static struct platform_driver w90x900ts_driver = {
 326         .probe          = w90x900ts_probe,
 327         .remove         = __devexit_p(w90x900ts_remove),
 328         .driver         = {
 329                 .name   = "w90x900-ts",
 330                 .owner  = THIS_MODULE,
 331         },
 332 };
 333
 334 static int __init w90x900ts_init(void)
 335 {
 336         return platform_driver_register(&w90x900ts_driver);
 337 }
 338
 339 static void __exit w90x900ts_exit(void)
 340 {
 341         platform_driver_unregister(&w90x900ts_driver);
 342 }
 343
 344 module_init(w90x900ts_init);
 345 module_exit(w90x900ts_exit);
 346
 347 MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
 348 MODULE_DESCRIPTION("w90p910 touch screen driver!");
 349 MODULE_LICENSE("GPL");
 350 MODULE_ALIAS("platform:w90p910-ts");