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