drivers/input/keyboard/tnetv107x-keypad.c

   1 /*
   2  * Texas Instruments TNETV107X Keypad Driver
   3  *
   4  * Copyright (C) 2010 Texas Instruments
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation version 2.
   9  *
  10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  11  * kind, whether express or implied; without even the implied warranty
  12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/err.h>
  18 #include <linux/errno.h>
  19 #include <linux/input.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/slab.h>
  23 #include <linux/delay.h>
  24 #include <linux/io.h>
  25 #include <linux/clk.h>
  26 #include <linux/input/matrix_keypad.h>
  27
  28 #define BITS(x)                 (BIT(x) - 1)
  29
  30 #define KEYPAD_ROWS             9
  31 #define KEYPAD_COLS             9
  32
  33 #define DEBOUNCE_MIN            0x400ul
  34 #define DEBOUNCE_MAX            0x3ffffffful
  35
  36 struct keypad_regs {
  37         u32     rev;
  38         u32     mode;
  39         u32     mask;
  40         u32     pol;
  41         u32     dclock;
  42         u32     rclock;
  43         u32     stable_cnt;
  44         u32     in_en;
  45         u32     out;
  46         u32     out_en;
  47         u32     in;
  48         u32     lock;
  49         u32     pres[3];
  50 };
  51
  52 #define keypad_read(kp, reg)            __raw_readl(&(kp)->regs->reg)
  53 #define keypad_write(kp, reg, val)      __raw_writel(val, &(kp)->regs->reg)
  54
  55 struct keypad_data {
  56         struct input_dev                *input_dev;
  57         struct resource                 *res;
  58         struct keypad_regs __iomem      *regs;
  59         struct clk                      *clk;
  60         struct device                   *dev;
  61         spinlock_t                      lock;
  62         u32                             irq_press;
  63         u32                             irq_release;
  64         int                             rows, cols, row_shift;
  65         int                             debounce_ms, active_low;
  66         u32                             prev_keys[3];
  67         unsigned short                  keycodes[];
  68 };
  69
  70 static irqreturn_t keypad_irq(int irq, void *data)
  71 {
  72         struct keypad_data *kp = data;
  73         int i, bit, val, row, col, code;
  74         unsigned long flags;
  75         u32 curr_keys[3];
  76         u32 change;
  77
  78         spin_lock_irqsave(&kp->lock, flags);
  79
  80         memset(curr_keys, 0, sizeof(curr_keys));
  81         if (irq == kp->irq_press)
  82                 for (i = 0; i < 3; i++)
  83                         curr_keys[i] = keypad_read(kp, pres[i]);
  84
  85         for (i = 0; i < 3; i++) {
  86                 change = curr_keys[i] ^ kp->prev_keys[i];
  87
  88                 while (change) {
  89                         bit     = fls(change) - 1;
  90                         change ^= BIT(bit);
  91                         val     = curr_keys[i] & BIT(bit);
  92                         bit    += i * 32;
  93                         row     = bit / KEYPAD_COLS;
  94                         col     = bit % KEYPAD_COLS;
  95
  96                         code = MATRIX_SCAN_CODE(row, col, kp->row_shift);
  97                         input_event(kp->input_dev, EV_MSC, MSC_SCAN, code);
  98                         input_report_key(kp->input_dev, kp->keycodes[code],
  99                                          val);
 100                 }
 101         }
 102         input_sync(kp->input_dev);
 103         memcpy(kp->prev_keys, curr_keys, sizeof(curr_keys));
 104
 105         if (irq == kp->irq_press)
 106                 keypad_write(kp, lock, 0); /* Allow hardware updates */
 107
 108         spin_unlock_irqrestore(&kp->lock, flags);
 109
 110         return IRQ_HANDLED;
 111 }
 112
 113 static int keypad_start(struct input_dev *dev)
 114 {
 115         struct keypad_data *kp = input_get_drvdata(dev);
 116         unsigned long mask, debounce, clk_rate_khz;
 117         unsigned long flags;
 118
 119         clk_enable(kp->clk);
 120         clk_rate_khz = clk_get_rate(kp->clk) / 1000;
 121
 122         spin_lock_irqsave(&kp->lock, flags);
 123
 124         /* Initialize device registers */
 125         keypad_write(kp, mode, 0);
 126
 127         mask  = BITS(kp->rows) << KEYPAD_COLS;
 128         mask |= BITS(kp->cols);
 129         keypad_write(kp, mask, ~mask);
 130
 131         keypad_write(kp, pol, kp->active_low ? 0 : 0x3ffff);
 132         keypad_write(kp, stable_cnt, 3);
 133
 134         debounce = kp->debounce_ms * clk_rate_khz;
 135         debounce = clamp(debounce, DEBOUNCE_MIN, DEBOUNCE_MAX);
 136         keypad_write(kp, dclock, debounce);
 137         keypad_write(kp, rclock, 4 * debounce);
 138
 139         keypad_write(kp, in_en, 1);
 140
 141         spin_unlock_irqrestore(&kp->lock, flags);
 142
 143         return 0;
 144 }
 145
 146 static void keypad_stop(struct input_dev *dev)
 147 {
 148         struct keypad_data *kp = input_get_drvdata(dev);
 149
 150         synchronize_irq(kp->irq_press);
 151         synchronize_irq(kp->irq_release);
 152         clk_disable(kp->clk);
 153 }
 154
 155 static int __devinit keypad_probe(struct platform_device *pdev)
 156 {
 157         const struct matrix_keypad_platform_data *pdata;
 158         const struct matrix_keymap_data *keymap_data;
 159         struct device *dev = &pdev->dev;
 160         struct keypad_data *kp;
 161         int error = 0, sz, row_shift;
 162         u32 rev = 0;
 163
 164         pdata = pdev->dev.platform_data;
 165         if (!pdata) {
 166                 dev_err(dev, "cannot find device data\n");
 167                 return -EINVAL;
 168         }
 169
 170         keymap_data = pdata->keymap_data;
 171         if (!keymap_data) {
 172                 dev_err(dev, "cannot find keymap data\n");
 173                 return -EINVAL;
 174         }
 175
 176         row_shift = get_count_order(pdata->num_col_gpios);
 177         sz  = offsetof(struct keypad_data, keycodes);
 178         sz += (pdata->num_row_gpios << row_shift) * sizeof(kp->keycodes[0]);
 179         kp = kzalloc(sz, GFP_KERNEL);
 180         if (!kp) {
 181                 dev_err(dev, "cannot allocate device info\n");
 182                 return -ENOMEM;
 183         }
 184
 185         kp->dev  = dev;
 186         kp->rows = pdata->num_row_gpios;
 187         kp->cols = pdata->num_col_gpios;
 188         kp->row_shift = row_shift;
 189         platform_set_drvdata(pdev, kp);
 190         spin_lock_init(&kp->lock);
 191
 192         kp->irq_press   = platform_get_irq_byname(pdev, "press");
 193         kp->irq_release = platform_get_irq_byname(pdev, "release");
 194         if (kp->irq_press < 0 || kp->irq_release < 0) {
 195                 dev_err(dev, "cannot determine device interrupts\n");
 196                 error = -ENODEV;
 197                 goto error_res;
 198         }
 199
 200         kp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 201         if (!kp->res) {
 202                 dev_err(dev, "cannot determine register area\n");
 203                 error = -ENODEV;
 204                 goto error_res;
 205         }
 206
 207         if (!request_mem_region(kp->res->start, resource_size(kp->res),
 208                                 pdev->name)) {
 209                 dev_err(dev, "cannot claim register memory\n");
 210                 kp->res = NULL;
 211                 error = -EINVAL;
 212                 goto error_res;
 213         }
 214
 215         kp->regs = ioremap(kp->res->start, resource_size(kp->res));
 216         if (!kp->regs) {
 217                 dev_err(dev, "cannot map register memory\n");
 218                 error = -ENOMEM;
 219                 goto error_map;
 220         }
 221
 222         kp->clk = clk_get(dev, NULL);
 223         if (IS_ERR(kp->clk)) {
 224                 dev_err(dev, "cannot claim device clock\n");
 225                 error = PTR_ERR(kp->clk);
 226                 goto error_clk;
 227         }
 228
 229         error = request_threaded_irq(kp->irq_press, NULL, keypad_irq, 0,
 230                                      dev_name(dev), kp);
 231         if (error < 0) {
 232                 dev_err(kp->dev, "Could not allocate keypad press key irq\n");
 233                 goto error_irq_press;
 234         }
 235
 236         error = request_threaded_irq(kp->irq_release, NULL, keypad_irq, 0,
 237                                      dev_name(dev), kp);
 238         if (error < 0) {
 239                 dev_err(kp->dev, "Could not allocate keypad release key irq\n");
 240                 goto error_irq_release;
 241         }
 242
 243         kp->input_dev = input_allocate_device();
 244         if (!kp->input_dev) {
 245                 dev_err(dev, "cannot allocate input device\n");
 246                 error = -ENOMEM;
 247                 goto error_input;
 248         }
 249         input_set_drvdata(kp->input_dev, kp);
 250
 251         kp->input_dev->name       = pdev->name;
 252         kp->input_dev->dev.parent = &pdev->dev;
 253         kp->input_dev->open       = keypad_start;
 254         kp->input_dev->close      = keypad_stop;
 255         kp->input_dev->evbit[0]   = BIT_MASK(EV_KEY);
 256         if (!pdata->no_autorepeat)
 257                 kp->input_dev->evbit[0] |= BIT_MASK(EV_REP);
 258
 259         clk_enable(kp->clk);
 260         rev = keypad_read(kp, rev);
 261         kp->input_dev->id.bustype = BUS_HOST;
 262         kp->input_dev->id.product = ((rev >>  8) & 0x07);
 263         kp->input_dev->id.version = ((rev >> 16) & 0xfff);
 264         clk_disable(kp->clk);
 265
 266         kp->input_dev->keycode     = kp->keycodes;
 267         kp->input_dev->keycodesize = sizeof(kp->keycodes[0]);
 268         kp->input_dev->keycodemax  = kp->rows << kp->row_shift;
 269
 270         matrix_keypad_build_keymap(keymap_data, kp->row_shift, kp->keycodes,
 271                                    kp->input_dev->keybit);
 272
 273         input_set_capability(kp->input_dev, EV_MSC, MSC_SCAN);
 274
 275         error = input_register_device(kp->input_dev);
 276         if (error < 0) {
 277                 dev_err(dev, "Could not register input device\n");
 278                 goto error_reg;
 279         }
 280
 281         return 0;
 282
 283
 284 error_reg:
 285         input_free_device(kp->input_dev);
 286 error_input:
 287         free_irq(kp->irq_release, kp);
 288 error_irq_release:
 289         free_irq(kp->irq_press, kp);
 290 error_irq_press:
 291         clk_put(kp->clk);
 292 error_clk:
 293         iounmap(kp->regs);
 294 error_map:
 295         release_mem_region(kp->res->start, resource_size(kp->res));
 296 error_res:
 297         platform_set_drvdata(pdev, NULL);
 298         kfree(kp);
 299         return error;
 300 }
 301
 302 static int __devexit keypad_remove(struct platform_device *pdev)
 303 {
 304         struct keypad_data *kp = platform_get_drvdata(pdev);
 305
 306         free_irq(kp->irq_press, kp);
 307         free_irq(kp->irq_release, kp);
 308         input_unregister_device(kp->input_dev);
 309         clk_put(kp->clk);
 310         iounmap(kp->regs);
 311         release_mem_region(kp->res->start, resource_size(kp->res));
 312         platform_set_drvdata(pdev, NULL);
 313         kfree(kp);
 314
 315         return 0;
 316 }
 317
 318 static struct platform_driver keypad_driver = {
 319         .probe          = keypad_probe,
 320         .remove         = __devexit_p(keypad_remove),
 321         .driver.name    = "tnetv107x-keypad",
 322         .driver.owner   = THIS_MODULE,
 323 };
 324
 325 static int __init keypad_init(void)
 326 {
 327         return platform_driver_register(&keypad_driver);
 328 }
 329
 330 static void __exit keypad_exit(void)
 331 {
 332         platform_driver_unregister(&keypad_driver);
 333 }
 334
 335 module_init(keypad_init);
 336 module_exit(keypad_exit);
 337
 338 MODULE_AUTHOR("Cyril Chemparathy");
 339 MODULE_DESCRIPTION("TNETV107X Keypad Driver");
 340 MODULE_ALIAS("platform: tnetv107x-keypad");
 341 MODULE_LICENSE("GPL");