drivers/input/keyboard/ep93xx_keypad.c

   1 /*
   2  * Driver for the Cirrus EP93xx matrix keypad controller.
   3  *
   4  * Copyright (c) 2008 H Hartley Sweeten <hsweeten@visionengravers.com>
   5  *
   6  * Based on the pxa27x matrix keypad controller by Rodolfo Giometti.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * NOTE:
  13  *
  14  * The 3-key reset is triggered by pressing the 3 keys in
  15  * Row 0, Columns 2, 4, and 7 at the same time.  This action can
  16  * be disabled by setting the EP93XX_KEYPAD_DISABLE_3_KEY flag.
  17  *
  18  * Normal operation for the matrix does not autorepeat the key press.
  19  * This action can be enabled by setting the EP93XX_KEYPAD_AUTOREPEAT
  20  * flag.
  21  */
  22
  23 #include <linux/platform_device.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/clk.h>
  26 #include <linux/io.h>
  27 #include <linux/input/matrix_keypad.h>
  28
  29 #include <mach/hardware.h>
  30 #include <mach/ep93xx_keypad.h>
  31
  32 /*
  33  * Keypad Interface Register offsets
  34  */
  35 #define KEY_INIT                0x00    /* Key Scan Initialization register */
  36 #define KEY_DIAG                0x04    /* Key Scan Diagnostic register */
  37 #define KEY_REG                 0x08    /* Key Value Capture register */
  38
  39 /* Key Scan Initialization Register bit defines */
  40 #define KEY_INIT_DBNC_MASK      (0x00ff0000)
  41 #define KEY_INIT_DBNC_SHIFT     (16)
  42 #define KEY_INIT_DIS3KY         (1<<15)
  43 #define KEY_INIT_DIAG           (1<<14)
  44 #define KEY_INIT_BACK           (1<<13)
  45 #define KEY_INIT_T2             (1<<12)
  46 #define KEY_INIT_PRSCL_MASK     (0x000003ff)
  47 #define KEY_INIT_PRSCL_SHIFT    (0)
  48
  49 /* Key Scan Diagnostic Register bit defines */
  50 #define KEY_DIAG_MASK           (0x0000003f)
  51 #define KEY_DIAG_SHIFT          (0)
  52
  53 /* Key Value Capture Register bit defines */
  54 #define KEY_REG_K               (1<<15)
  55 #define KEY_REG_INT             (1<<14)
  56 #define KEY_REG_2KEYS           (1<<13)
  57 #define KEY_REG_1KEY            (1<<12)
  58 #define KEY_REG_KEY2_MASK       (0x00000fc0)
  59 #define KEY_REG_KEY2_SHIFT      (6)
  60 #define KEY_REG_KEY1_MASK       (0x0000003f)
  61 #define KEY_REG_KEY1_SHIFT      (0)
  62
  63 #define EP93XX_MATRIX_SIZE      (EP93XX_MATRIX_ROWS * EP93XX_MATRIX_COLS)
  64
  65 struct ep93xx_keypad {
  66         struct ep93xx_keypad_platform_data *pdata;
  67         struct input_dev *input_dev;
  68         struct clk *clk;
  69
  70         void __iomem *mmio_base;
  71
  72         unsigned int matrix_keycodes[EP93XX_MATRIX_SIZE];
  73
  74         int key1;
  75         int key2;
  76
  77         int irq;
  78
  79         bool enabled;
  80 };
  81
  82 static void ep93xx_keypad_build_keycode(struct ep93xx_keypad *keypad)
  83 {
  84         struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
  85         struct input_dev *input_dev = keypad->input_dev;
  86         unsigned int *key;
  87         int i;
  88
  89         key = &pdata->matrix_key_map[0];
  90         for (i = 0; i < pdata->matrix_key_map_size; i++, key++) {
  91                 int row = KEY_ROW(*key);
  92                 int col = KEY_COL(*key);
  93                 int code = KEY_VAL(*key);
  94
  95                 keypad->matrix_keycodes[(row << 3) + col] = code;
  96                 __set_bit(code, input_dev->keybit);
  97         }
  98 }
  99
 100 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
 101 {
 102         struct ep93xx_keypad *keypad = dev_id;
 103         struct input_dev *input_dev = keypad->input_dev;
 104         unsigned int status;
 105         int keycode, key1, key2;
 106
 107         status = __raw_readl(keypad->mmio_base + KEY_REG);
 108
 109         keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
 110         key1 = keypad->matrix_keycodes[keycode];
 111
 112         keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
 113         key2 = keypad->matrix_keycodes[keycode];
 114
 115         if (status & KEY_REG_2KEYS) {
 116                 if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
 117                         input_report_key(input_dev, keypad->key1, 0);
 118
 119                 if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
 120                         input_report_key(input_dev, keypad->key2, 0);
 121
 122                 input_report_key(input_dev, key1, 1);
 123                 input_report_key(input_dev, key2, 1);
 124
 125                 keypad->key1 = key1;
 126                 keypad->key2 = key2;
 127
 128         } else if (status & KEY_REG_1KEY) {
 129                 if (keypad->key1 && key1 != keypad->key1)
 130                         input_report_key(input_dev, keypad->key1, 0);
 131
 132                 if (keypad->key2 && key1 != keypad->key2)
 133                         input_report_key(input_dev, keypad->key2, 0);
 134
 135                 input_report_key(input_dev, key1, 1);
 136
 137                 keypad->key1 = key1;
 138                 keypad->key2 = 0;
 139
 140         } else {
 141                 input_report_key(input_dev, keypad->key1, 0);
 142                 input_report_key(input_dev, keypad->key2, 0);
 143
 144                 keypad->key1 = keypad->key2 = 0;
 145         }
 146         input_sync(input_dev);
 147
 148         return IRQ_HANDLED;
 149 }
 150
 151 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
 152 {
 153         struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
 154         unsigned int val = 0;
 155
 156         if (pdata->flags & EP93XX_KEYPAD_KDIV)
 157                 clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV4);
 158         else
 159                 clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV16);
 160
 161         if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
 162                 val |= KEY_INIT_DIS3KY;
 163         if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
 164                 val |= KEY_INIT_DIAG;
 165         if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
 166                 val |= KEY_INIT_BACK;
 167         if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
 168                 val |= KEY_INIT_T2;
 169
 170         val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
 171
 172         val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
 173
 174         __raw_writel(val, keypad->mmio_base + KEY_INIT);
 175 }
 176
 177 static int ep93xx_keypad_open(struct input_dev *pdev)
 178 {
 179         struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
 180
 181         if (!keypad->enabled) {
 182                 ep93xx_keypad_config(keypad);
 183                 clk_enable(keypad->clk);
 184                 keypad->enabled = true;
 185         }
 186
 187         return 0;
 188 }
 189
 190 static void ep93xx_keypad_close(struct input_dev *pdev)
 191 {
 192         struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
 193
 194         if (keypad->enabled) {
 195                 clk_disable(keypad->clk);
 196                 keypad->enabled = false;
 197         }
 198 }
 199
 200
 201 #ifdef CONFIG_PM
 202 /*
 203  * NOTE: I don't know if this is correct, or will work on the ep93xx.
 204  *
 205  * None of the existing ep93xx drivers have power management support.
 206  * But, this is basically what the pxa27x_keypad driver does.
 207  */
 208 static int ep93xx_keypad_suspend(struct platform_device *pdev,
 209                                  pm_message_t state)
 210 {
 211         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 212         struct input_dev *input_dev = keypad->input_dev;
 213
 214         mutex_lock(&input_dev->mutex);
 215
 216         if (keypad->enabled) {
 217                 clk_disable(keypad->clk);
 218                 keypad->enabled = false;
 219         }
 220
 221         mutex_unlock(&input_dev->mutex);
 222
 223         if (device_may_wakeup(&pdev->dev))
 224                 enable_irq_wake(keypad->irq);
 225
 226         return 0;
 227 }
 228
 229 static int ep93xx_keypad_resume(struct platform_device *pdev)
 230 {
 231         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 232         struct input_dev *input_dev = keypad->input_dev;
 233
 234         if (device_may_wakeup(&pdev->dev))
 235                 disable_irq_wake(keypad->irq);
 236
 237         mutex_lock(&input_dev->mutex);
 238
 239         if (input_dev->users) {
 240                 if (!keypad->enabled) {
 241                         ep93xx_keypad_config(keypad);
 242                         clk_enable(keypad->clk);
 243                         keypad->enabled = true;
 244                 }
 245         }
 246
 247         mutex_unlock(&input_dev->mutex);
 248
 249         return 0;
 250 }
 251 #else   /* !CONFIG_PM */
 252 #define ep93xx_keypad_suspend   NULL
 253 #define ep93xx_keypad_resume    NULL
 254 #endif  /* !CONFIG_PM */
 255
 256 static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
 257 {
 258         struct ep93xx_keypad *keypad;
 259         struct input_dev *input_dev;
 260         struct resource *res;
 261         int err;
 262
 263         keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
 264         if (!keypad)
 265                 return -ENOMEM;
 266
 267         keypad->pdata = pdev->dev.platform_data;
 268         if (!keypad->pdata) {
 269                 err = -EINVAL;
 270                 goto failed_free;
 271         }
 272
 273         keypad->irq = platform_get_irq(pdev, 0);
 274         if (!keypad->irq) {
 275                 err = -ENXIO;
 276                 goto failed_free;
 277         }
 278
 279         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 280         if (!res) {
 281                 err = -ENXIO;
 282                 goto failed_free;
 283         }
 284
 285         res = request_mem_region(res->start, resource_size(res), pdev->name);
 286         if (!res) {
 287                 err = -EBUSY;
 288                 goto failed_free;
 289         }
 290
 291         keypad->mmio_base = ioremap(res->start, resource_size(res));
 292         if (keypad->mmio_base == NULL) {
 293                 err = -ENXIO;
 294                 goto failed_free_mem;
 295         }
 296
 297         err = ep93xx_keypad_acquire_gpio(pdev);
 298         if (err)
 299                 goto failed_free_io;
 300
 301         keypad->clk = clk_get(&pdev->dev, NULL);
 302         if (IS_ERR(keypad->clk)) {
 303                 err = PTR_ERR(keypad->clk);
 304                 goto failed_free_gpio;
 305         }
 306
 307         input_dev = input_allocate_device();
 308         if (!input_dev) {
 309                 err = -ENOMEM;
 310                 goto failed_put_clk;
 311         }
 312
 313         keypad->input_dev = input_dev;
 314
 315         input_dev->name = pdev->name;
 316         input_dev->id.bustype = BUS_HOST;
 317         input_dev->open = ep93xx_keypad_open;
 318         input_dev->close = ep93xx_keypad_close;
 319         input_dev->dev.parent = &pdev->dev;
 320         input_dev->keycode = keypad->matrix_keycodes;
 321         input_dev->keycodesize = sizeof(keypad->matrix_keycodes[0]);
 322         input_dev->keycodemax = ARRAY_SIZE(keypad->matrix_keycodes);
 323
 324         input_set_drvdata(input_dev, keypad);
 325
 326         input_dev->evbit[0] = BIT_MASK(EV_KEY);
 327         if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
 328                 input_dev->evbit[0] |= BIT_MASK(EV_REP);
 329
 330         ep93xx_keypad_build_keycode(keypad);
 331         platform_set_drvdata(pdev, keypad);
 332
 333         err = request_irq(keypad->irq, ep93xx_keypad_irq_handler,
 334                           IRQF_DISABLED, pdev->name, keypad);
 335         if (err)
 336                 goto failed_free_dev;
 337
 338         err = input_register_device(input_dev);
 339         if (err)
 340                 goto failed_free_irq;
 341
 342         device_init_wakeup(&pdev->dev, 1);
 343
 344         return 0;
 345
 346 failed_free_irq:
 347         free_irq(keypad->irq, pdev);
 348         platform_set_drvdata(pdev, NULL);
 349 failed_free_dev:
 350         input_free_device(input_dev);
 351 failed_put_clk:
 352         clk_put(keypad->clk);
 353 failed_free_gpio:
 354         ep93xx_keypad_release_gpio(pdev);
 355 failed_free_io:
 356         iounmap(keypad->mmio_base);
 357 failed_free_mem:
 358         release_mem_region(res->start, resource_size(res));
 359 failed_free:
 360         kfree(keypad);
 361         return err;
 362 }
 363
 364 static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
 365 {
 366         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 367         struct resource *res;
 368
 369         free_irq(keypad->irq, pdev);
 370
 371         platform_set_drvdata(pdev, NULL);
 372
 373         if (keypad->enabled)
 374                 clk_disable(keypad->clk);
 375         clk_put(keypad->clk);
 376
 377         input_unregister_device(keypad->input_dev);
 378
 379         ep93xx_keypad_release_gpio(pdev);
 380
 381         iounmap(keypad->mmio_base);
 382
 383         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 384         release_mem_region(res->start, resource_size(res));
 385
 386         kfree(keypad);
 387
 388         return 0;
 389 }
 390
 391 static struct platform_driver ep93xx_keypad_driver = {
 392         .driver         = {
 393                 .name   = "ep93xx-keypad",
 394                 .owner  = THIS_MODULE,
 395         },
 396         .probe          = ep93xx_keypad_probe,
 397         .remove         = __devexit_p(ep93xx_keypad_remove),
 398         .suspend        = ep93xx_keypad_suspend,
 399         .resume         = ep93xx_keypad_resume,
 400 };
 401
 402 static int __init ep93xx_keypad_init(void)
 403 {
 404         return platform_driver_register(&ep93xx_keypad_driver);
 405 }
 406
 407 static void __exit ep93xx_keypad_exit(void)
 408 {
 409         platform_driver_unregister(&ep93xx_keypad_driver);
 410 }
 411
 412 module_init(ep93xx_keypad_init);
 413 module_exit(ep93xx_keypad_exit);
 414
 415 MODULE_LICENSE("GPL");
 416 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
 417 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
 418 MODULE_ALIAS("platform:ep93xx-keypad");