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