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 short keycodes[EP93XX_MATRIX_SIZE];
  73
  74         int key1;
  75         int key2;
  76
  77         int irq;
  78
  79         bool enabled;
  80 };
  81
  82 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
  83 {
  84         struct ep93xx_keypad *keypad = dev_id;
  85         struct input_dev *input_dev = keypad->input_dev;
  86         unsigned int status;
  87         int keycode, key1, key2;
  88
  89         status = __raw_readl(keypad->mmio_base + KEY_REG);
  90
  91         keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
  92         key1 = keypad->keycodes[keycode];
  93
  94         keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
  95         key2 = keypad->keycodes[keycode];
  96
  97         if (status & KEY_REG_2KEYS) {
  98                 if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
  99                         input_report_key(input_dev, keypad->key1, 0);
 100
 101                 if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
 102                         input_report_key(input_dev, keypad->key2, 0);
 103
 104                 input_report_key(input_dev, key1, 1);
 105                 input_report_key(input_dev, key2, 1);
 106
 107                 keypad->key1 = key1;
 108                 keypad->key2 = key2;
 109
 110         } else if (status & KEY_REG_1KEY) {
 111                 if (keypad->key1 && key1 != keypad->key1)
 112                         input_report_key(input_dev, keypad->key1, 0);
 113
 114                 if (keypad->key2 && key1 != keypad->key2)
 115                         input_report_key(input_dev, keypad->key2, 0);
 116
 117                 input_report_key(input_dev, key1, 1);
 118
 119                 keypad->key1 = key1;
 120                 keypad->key2 = 0;
 121
 122         } else {
 123                 input_report_key(input_dev, keypad->key1, 0);
 124                 input_report_key(input_dev, keypad->key2, 0);
 125
 126                 keypad->key1 = keypad->key2 = 0;
 127         }
 128         input_sync(input_dev);
 129
 130         return IRQ_HANDLED;
 131 }
 132
 133 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
 134 {
 135         struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
 136         unsigned int val = 0;
 137
 138         if (pdata->flags & EP93XX_KEYPAD_KDIV)
 139                 clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV4);
 140         else
 141                 clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV16);
 142
 143         if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
 144                 val |= KEY_INIT_DIS3KY;
 145         if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
 146                 val |= KEY_INIT_DIAG;
 147         if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
 148                 val |= KEY_INIT_BACK;
 149         if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
 150                 val |= KEY_INIT_T2;
 151
 152         val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
 153
 154         val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
 155
 156         __raw_writel(val, keypad->mmio_base + KEY_INIT);
 157 }
 158
 159 static int ep93xx_keypad_open(struct input_dev *pdev)
 160 {
 161         struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
 162
 163         if (!keypad->enabled) {
 164                 ep93xx_keypad_config(keypad);
 165                 clk_enable(keypad->clk);
 166                 keypad->enabled = true;
 167         }
 168
 169         return 0;
 170 }
 171
 172 static void ep93xx_keypad_close(struct input_dev *pdev)
 173 {
 174         struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
 175
 176         if (keypad->enabled) {
 177                 clk_disable(keypad->clk);
 178                 keypad->enabled = false;
 179         }
 180 }
 181
 182
 183 #ifdef CONFIG_PM
 184 /*
 185  * NOTE: I don't know if this is correct, or will work on the ep93xx.
 186  *
 187  * None of the existing ep93xx drivers have power management support.
 188  * But, this is basically what the pxa27x_keypad driver does.
 189  */
 190 static int ep93xx_keypad_suspend(struct platform_device *pdev,
 191                                  pm_message_t state)
 192 {
 193         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 194         struct input_dev *input_dev = keypad->input_dev;
 195
 196         mutex_lock(&input_dev->mutex);
 197
 198         if (keypad->enabled) {
 199                 clk_disable(keypad->clk);
 200                 keypad->enabled = false;
 201         }
 202
 203         mutex_unlock(&input_dev->mutex);
 204
 205         if (device_may_wakeup(&pdev->dev))
 206                 enable_irq_wake(keypad->irq);
 207
 208         return 0;
 209 }
 210
 211 static int ep93xx_keypad_resume(struct platform_device *pdev)
 212 {
 213         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 214         struct input_dev *input_dev = keypad->input_dev;
 215
 216         if (device_may_wakeup(&pdev->dev))
 217                 disable_irq_wake(keypad->irq);
 218
 219         mutex_lock(&input_dev->mutex);
 220
 221         if (input_dev->users) {
 222                 if (!keypad->enabled) {
 223                         ep93xx_keypad_config(keypad);
 224                         clk_enable(keypad->clk);
 225                         keypad->enabled = true;
 226                 }
 227         }
 228
 229         mutex_unlock(&input_dev->mutex);
 230
 231         return 0;
 232 }
 233 #else   /* !CONFIG_PM */
 234 #define ep93xx_keypad_suspend   NULL
 235 #define ep93xx_keypad_resume    NULL
 236 #endif  /* !CONFIG_PM */
 237
 238 static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
 239 {
 240         struct ep93xx_keypad *keypad;
 241         const struct matrix_keymap_data *keymap_data;
 242         struct input_dev *input_dev;
 243         struct resource *res;
 244         int err;
 245
 246         keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
 247         if (!keypad)
 248                 return -ENOMEM;
 249
 250         keypad->pdata = pdev->dev.platform_data;
 251         if (!keypad->pdata) {
 252                 err = -EINVAL;
 253                 goto failed_free;
 254         }
 255
 256         keymap_data = keypad->pdata->keymap_data;
 257         if (!keymap_data) {
 258                 err = -EINVAL;
 259                 goto failed_free;
 260         }
 261
 262         keypad->irq = platform_get_irq(pdev, 0);
 263         if (!keypad->irq) {
 264                 err = -ENXIO;
 265                 goto failed_free;
 266         }
 267
 268         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 269         if (!res) {
 270                 err = -ENXIO;
 271                 goto failed_free;
 272         }
 273
 274         res = request_mem_region(res->start, resource_size(res), pdev->name);
 275         if (!res) {
 276                 err = -EBUSY;
 277                 goto failed_free;
 278         }
 279
 280         keypad->mmio_base = ioremap(res->start, resource_size(res));
 281         if (keypad->mmio_base == NULL) {
 282                 err = -ENXIO;
 283                 goto failed_free_mem;
 284         }
 285
 286         err = ep93xx_keypad_acquire_gpio(pdev);
 287         if (err)
 288                 goto failed_free_io;
 289
 290         keypad->clk = clk_get(&pdev->dev, NULL);
 291         if (IS_ERR(keypad->clk)) {
 292                 err = PTR_ERR(keypad->clk);
 293                 goto failed_free_gpio;
 294         }
 295
 296         input_dev = input_allocate_device();
 297         if (!input_dev) {
 298                 err = -ENOMEM;
 299                 goto failed_put_clk;
 300         }
 301
 302         keypad->input_dev = input_dev;
 303
 304         input_dev->name = pdev->name;
 305         input_dev->id.bustype = BUS_HOST;
 306         input_dev->open = ep93xx_keypad_open;
 307         input_dev->close = ep93xx_keypad_close;
 308         input_dev->dev.parent = &pdev->dev;
 309         input_dev->keycode = keypad->keycodes;
 310         input_dev->keycodesize = sizeof(keypad->keycodes[0]);
 311         input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
 312
 313         input_set_drvdata(input_dev, keypad);
 314
 315         input_dev->evbit[0] = BIT_MASK(EV_KEY);
 316         if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
 317                 input_dev->evbit[0] |= BIT_MASK(EV_REP);
 318
 319         matrix_keypad_build_keymap(keymap_data, 3,
 320                                    input_dev->keycode, input_dev->keybit);
 321         platform_set_drvdata(pdev, keypad);
 322
 323         err = request_irq(keypad->irq, ep93xx_keypad_irq_handler,
 324                           IRQF_DISABLED, pdev->name, keypad);
 325         if (err)
 326                 goto failed_free_dev;
 327
 328         err = input_register_device(input_dev);
 329         if (err)
 330                 goto failed_free_irq;
 331
 332         device_init_wakeup(&pdev->dev, 1);
 333
 334         return 0;
 335
 336 failed_free_irq:
 337         free_irq(keypad->irq, pdev);
 338         platform_set_drvdata(pdev, NULL);
 339 failed_free_dev:
 340         input_free_device(input_dev);
 341 failed_put_clk:
 342         clk_put(keypad->clk);
 343 failed_free_gpio:
 344         ep93xx_keypad_release_gpio(pdev);
 345 failed_free_io:
 346         iounmap(keypad->mmio_base);
 347 failed_free_mem:
 348         release_mem_region(res->start, resource_size(res));
 349 failed_free:
 350         kfree(keypad);
 351         return err;
 352 }
 353
 354 static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
 355 {
 356         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 357         struct resource *res;
 358
 359         free_irq(keypad->irq, pdev);
 360
 361         platform_set_drvdata(pdev, NULL);
 362
 363         if (keypad->enabled)
 364                 clk_disable(keypad->clk);
 365         clk_put(keypad->clk);
 366
 367         input_unregister_device(keypad->input_dev);
 368
 369         ep93xx_keypad_release_gpio(pdev);
 370
 371         iounmap(keypad->mmio_base);
 372
 373         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 374         release_mem_region(res->start, resource_size(res));
 375
 376         kfree(keypad);
 377
 378         return 0;
 379 }
 380
 381 static struct platform_driver ep93xx_keypad_driver = {
 382         .driver         = {
 383                 .name   = "ep93xx-keypad",
 384                 .owner  = THIS_MODULE,
 385         },
 386         .probe          = ep93xx_keypad_probe,
 387         .remove         = __devexit_p(ep93xx_keypad_remove),
 388         .suspend        = ep93xx_keypad_suspend,
 389         .resume         = ep93xx_keypad_resume,
 390 };
 391
 392 static int __init ep93xx_keypad_init(void)
 393 {
 394         return platform_driver_register(&ep93xx_keypad_driver);
 395 }
 396
 397 static void __exit ep93xx_keypad_exit(void)
 398 {
 399         platform_driver_unregister(&ep93xx_keypad_driver);
 400 }
 401
 402 module_init(ep93xx_keypad_init);
 403 module_exit(ep93xx_keypad_exit);
 404
 405 MODULE_LICENSE("GPL");
 406 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
 407 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
 408 MODULE_ALIAS("platform:ep93xx-keypad");