drivers/input/keyboard/stmpe-keypad.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2010
   3  *
   4  * License Terms: GNU General Public License, version 2
   5  * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/input.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/input/matrix_keypad.h>
  15 #include <linux/mfd/stmpe.h>
  16
  17 /* These are at the same addresses in all STMPE variants */
  18 #define STMPE_KPC_COL                   0x60
  19 #define STMPE_KPC_ROW_MSB               0x61
  20 #define STMPE_KPC_ROW_LSB               0x62
  21 #define STMPE_KPC_CTRL_MSB              0x63
  22 #define STMPE_KPC_CTRL_LSB              0x64
  23 #define STMPE_KPC_COMBI_KEY_0           0x65
  24 #define STMPE_KPC_COMBI_KEY_1           0x66
  25 #define STMPE_KPC_COMBI_KEY_2           0x67
  26 #define STMPE_KPC_DATA_BYTE0            0x68
  27 #define STMPE_KPC_DATA_BYTE1            0x69
  28 #define STMPE_KPC_DATA_BYTE2            0x6a
  29 #define STMPE_KPC_DATA_BYTE3            0x6b
  30 #define STMPE_KPC_DATA_BYTE4            0x6c
  31
  32 #define STMPE_KPC_CTRL_LSB_SCAN         (0x1 << 0)
  33 #define STMPE_KPC_CTRL_LSB_DEBOUNCE     (0x7f << 1)
  34 #define STMPE_KPC_CTRL_MSB_SCAN_COUNT   (0xf << 4)
  35
  36 #define STMPE_KPC_ROW_MSB_ROWS          0xff
  37
  38 #define STMPE_KPC_DATA_UP               (0x1 << 7)
  39 #define STMPE_KPC_DATA_ROW              (0xf << 3)
  40 #define STMPE_KPC_DATA_COL              (0x7 << 0)
  41 #define STMPE_KPC_DATA_NOKEY_MASK       0x78
  42
  43 #define STMPE_KEYPAD_MAX_DEBOUNCE       127
  44 #define STMPE_KEYPAD_MAX_SCAN_COUNT     15
  45
  46 #define STMPE_KEYPAD_MAX_ROWS           8
  47 #define STMPE_KEYPAD_MAX_COLS           8
  48 #define STMPE_KEYPAD_ROW_SHIFT          3
  49 #define STMPE_KEYPAD_KEYMAP_SIZE        \
  50         (STMPE_KEYPAD_MAX_ROWS * STMPE_KEYPAD_MAX_COLS)
  51
  52 /**
  53  * struct stmpe_keypad_variant - model-specific attributes
  54  * @auto_increment: whether the KPC_DATA_BYTE register address
  55  *                  auto-increments on multiple read
  56  * @num_data: number of data bytes
  57  * @num_normal_data: number of normal keys' data bytes
  58  * @max_cols: maximum number of columns supported
  59  * @max_rows: maximum number of rows supported
  60  * @col_gpios: bitmask of gpios which can be used for columns
  61  * @row_gpios: bitmask of gpios which can be used for rows
  62  */
  63 struct stmpe_keypad_variant {
  64         bool            auto_increment;
  65         int             num_data;
  66         int             num_normal_data;
  67         int             max_cols;
  68         int             max_rows;
  69         unsigned int    col_gpios;
  70         unsigned int    row_gpios;
  71 };
  72
  73 static const struct stmpe_keypad_variant stmpe_keypad_variants[] = {
  74         [STMPE1601] = {
  75                 .auto_increment         = true,
  76                 .num_data               = 5,
  77                 .num_normal_data        = 3,
  78                 .max_cols               = 8,
  79                 .max_rows               = 8,
  80                 .col_gpios              = 0x000ff,      /* GPIO 0 - 7 */
  81                 .row_gpios              = 0x0ff00,      /* GPIO 8 - 15 */
  82         },
  83         [STMPE2401] = {
  84                 .auto_increment         = false,
  85                 .num_data               = 3,
  86                 .num_normal_data        = 2,
  87                 .max_cols               = 8,
  88                 .max_rows               = 12,
  89                 .col_gpios              = 0x0000ff,     /* GPIO 0 - 7*/
  90                 .row_gpios              = 0x1fef00,     /* GPIO 8-14, 16-20 */
  91         },
  92         [STMPE2403] = {
  93                 .auto_increment         = true,
  94                 .num_data               = 5,
  95                 .num_normal_data        = 3,
  96                 .max_cols               = 8,
  97                 .max_rows               = 12,
  98                 .col_gpios              = 0x0000ff,     /* GPIO 0 - 7*/
  99                 .row_gpios              = 0x1fef00,     /* GPIO 8-14, 16-20 */
 100         },
 101 };
 102
 103 struct stmpe_keypad {
 104         struct stmpe *stmpe;
 105         struct input_dev *input;
 106         const struct stmpe_keypad_variant *variant;
 107         const struct stmpe_keypad_platform_data *plat;
 108
 109         unsigned int rows;
 110         unsigned int cols;
 111
 112         unsigned short keymap[STMPE_KEYPAD_KEYMAP_SIZE];
 113 };
 114
 115 static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
 116 {
 117         const struct stmpe_keypad_variant *variant = keypad->variant;
 118         struct stmpe *stmpe = keypad->stmpe;
 119         int ret;
 120         int i;
 121
 122         if (variant->auto_increment)
 123                 return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
 124                                         variant->num_data, data);
 125
 126         for (i = 0; i < variant->num_data; i++) {
 127                 ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
 128                 if (ret < 0)
 129                         return ret;
 130
 131                 data[i] = ret;
 132         }
 133
 134         return 0;
 135 }
 136
 137 static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
 138 {
 139         struct stmpe_keypad *keypad = dev;
 140         struct input_dev *input = keypad->input;
 141         const struct stmpe_keypad_variant *variant = keypad->variant;
 142         u8 fifo[variant->num_data];
 143         int ret;
 144         int i;
 145
 146         ret = stmpe_keypad_read_data(keypad, fifo);
 147         if (ret < 0)
 148                 return IRQ_NONE;
 149
 150         for (i = 0; i < variant->num_normal_data; i++) {
 151                 u8 data = fifo[i];
 152                 int row = (data & STMPE_KPC_DATA_ROW) >> 3;
 153                 int col = data & STMPE_KPC_DATA_COL;
 154                 int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
 155                 bool up = data & STMPE_KPC_DATA_UP;
 156
 157                 if ((data & STMPE_KPC_DATA_NOKEY_MASK)
 158                         == STMPE_KPC_DATA_NOKEY_MASK)
 159                         continue;
 160
 161                 input_event(input, EV_MSC, MSC_SCAN, code);
 162                 input_report_key(input, keypad->keymap[code], !up);
 163                 input_sync(input);
 164         }
 165
 166         return IRQ_HANDLED;
 167 }
 168
 169 static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
 170 {
 171         const struct stmpe_keypad_variant *variant = keypad->variant;
 172         unsigned int col_gpios = variant->col_gpios;
 173         unsigned int row_gpios = variant->row_gpios;
 174         struct stmpe *stmpe = keypad->stmpe;
 175         unsigned int pins = 0;
 176         int i;
 177
 178         /*
 179          * Figure out which pins need to be set to the keypad alternate
 180          * function.
 181          *
 182          * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
 183          * for the keypad.
 184          *
 185          * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
 186          * for the keypad) are used on the board.
 187          */
 188
 189         for (i = 0; i < variant->max_cols; i++) {
 190                 int num = __ffs(col_gpios);
 191
 192                 if (keypad->cols & (1 << i))
 193                         pins |= 1 << num;
 194
 195                 col_gpios &= ~(1 << num);
 196         }
 197
 198         for (i = 0; i < variant->max_rows; i++) {
 199                 int num = __ffs(row_gpios);
 200
 201                 if (keypad->rows & (1 << i))
 202                         pins |= 1 << num;
 203
 204                 row_gpios &= ~(1 << num);
 205         }
 206
 207         return stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD);
 208 }
 209
 210 static int stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
 211 {
 212         const struct stmpe_keypad_platform_data *plat = keypad->plat;
 213         const struct stmpe_keypad_variant *variant = keypad->variant;
 214         struct stmpe *stmpe = keypad->stmpe;
 215         int ret;
 216
 217         if (plat->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
 218                 return -EINVAL;
 219
 220         if (plat->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
 221                 return -EINVAL;
 222
 223         ret = stmpe_enable(stmpe, STMPE_BLOCK_KEYPAD);
 224         if (ret < 0)
 225                 return ret;
 226
 227         ret = stmpe_keypad_altfunc_init(keypad);
 228         if (ret < 0)
 229                 return ret;
 230
 231         ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, keypad->cols);
 232         if (ret < 0)
 233                 return ret;
 234
 235         ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, keypad->rows);
 236         if (ret < 0)
 237                 return ret;
 238
 239         if (variant->max_rows > 8) {
 240                 ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
 241                                      STMPE_KPC_ROW_MSB_ROWS,
 242                                      keypad->rows >> 8);
 243                 if (ret < 0)
 244                         return ret;
 245         }
 246
 247         ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
 248                              STMPE_KPC_CTRL_MSB_SCAN_COUNT,
 249                              plat->scan_count << 4);
 250         if (ret < 0)
 251                 return ret;
 252
 253         return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
 254                               STMPE_KPC_CTRL_LSB_SCAN |
 255                               STMPE_KPC_CTRL_LSB_DEBOUNCE,
 256                               STMPE_KPC_CTRL_LSB_SCAN |
 257                               (plat->debounce_ms << 1));
 258 }
 259
 260 static void stmpe_keypad_fill_used_pins(struct stmpe_keypad *keypad)
 261 {
 262         int row, col;
 263
 264         for (row = 0; row < STMPE_KEYPAD_MAX_ROWS; row++) {
 265                 for (col = 0; col < STMPE_KEYPAD_MAX_COLS; col++) {
 266                         int code = MATRIX_SCAN_CODE(row, col,
 267                                                 STMPE_KEYPAD_ROW_SHIFT);
 268                         if (keypad->keymap[code] != KEY_RESERVED) {
 269                                 keypad->rows |= 1 << row;
 270                                 keypad->cols |= 1 << col;
 271                         }
 272                 }
 273         }
 274 }
 275
 276 #ifdef CONFIG_OF
 277 static const struct stmpe_keypad_platform_data *
 278 stmpe_keypad_of_probe(struct device *dev)
 279 {
 280         struct device_node *np = dev->of_node;
 281         struct stmpe_keypad_platform_data *plat;
 282
 283         if (!np)
 284                 return ERR_PTR(-ENODEV);
 285
 286         plat = devm_kzalloc(dev, sizeof(*plat), GFP_KERNEL);
 287         if (!plat)
 288                 return ERR_PTR(-ENOMEM);
 289
 290         of_property_read_u32(np, "debounce-interval", &plat->debounce_ms);
 291         of_property_read_u32(np, "st,scan-count", &plat->scan_count);
 292
 293         plat->no_autorepeat = of_property_read_bool(np, "st,no-autorepeat");
 294
 295         return plat;
 296 }
 297 #else
 298 static inline const struct stmpe_keypad_platform_data *
 299 stmpe_keypad_of_probe(struct device *dev)
 300 {
 301         return ERR_PTR(-EINVAL);
 302 }
 303 #endif
 304
 305 static int stmpe_keypad_probe(struct platform_device *pdev)
 306 {
 307         struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
 308         const struct stmpe_keypad_platform_data *plat;
 309         struct stmpe_keypad *keypad;
 310         struct input_dev *input;
 311         int error;
 312         int irq;
 313
 314         plat = stmpe->pdata->keypad;
 315         if (!plat) {
 316                 plat = stmpe_keypad_of_probe(&pdev->dev);
 317                 if (IS_ERR(plat))
 318                         return PTR_ERR(plat);
 319         }
 320
 321         irq = platform_get_irq(pdev, 0);
 322         if (irq < 0)
 323                 return irq;
 324
 325         keypad = devm_kzalloc(&pdev->dev, sizeof(struct stmpe_keypad),
 326                               GFP_KERNEL);
 327         if (!keypad)
 328                 return -ENOMEM;
 329
 330         input = devm_input_allocate_device(&pdev->dev);
 331         if (!input)
 332                 return -ENOMEM;
 333
 334         input->name = "STMPE keypad";
 335         input->id.bustype = BUS_I2C;
 336         input->dev.parent = &pdev->dev;
 337
 338         error = matrix_keypad_build_keymap(plat->keymap_data, NULL,
 339                                            STMPE_KEYPAD_MAX_ROWS,
 340                                            STMPE_KEYPAD_MAX_COLS,
 341                                            keypad->keymap, input);
 342         if (error)
 343                 return error;
 344
 345         input_set_capability(input, EV_MSC, MSC_SCAN);
 346         if (!plat->no_autorepeat)
 347                 __set_bit(EV_REP, input->evbit);
 348
 349         stmpe_keypad_fill_used_pins(keypad);
 350
 351         keypad->stmpe = stmpe;
 352         keypad->plat = plat;
 353         keypad->input = input;
 354         keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
 355
 356         error = stmpe_keypad_chip_init(keypad);
 357         if (error < 0)
 358                 return error;
 359
 360         error = devm_request_threaded_irq(&pdev->dev, irq,
 361                                           NULL, stmpe_keypad_irq,
 362                                           IRQF_ONESHOT, "stmpe-keypad", keypad);
 363         if (error) {
 364                 dev_err(&pdev->dev, "unable to get irq: %d\n", error);
 365                 return error;
 366         }
 367
 368         error = input_register_device(input);
 369         if (error) {
 370                 dev_err(&pdev->dev,
 371                         "unable to register input device: %d\n", error);
 372                 return error;
 373         }
 374
 375         platform_set_drvdata(pdev, keypad);
 376
 377         return 0;
 378 }
 379
 380 static int stmpe_keypad_remove(struct platform_device *pdev)
 381 {
 382         struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
 383
 384         stmpe_disable(keypad->stmpe, STMPE_BLOCK_KEYPAD);
 385
 386         return 0;
 387 }
 388
 389 static struct platform_driver stmpe_keypad_driver = {
 390         .driver.name    = "stmpe-keypad",
 391         .driver.owner   = THIS_MODULE,
 392         .probe          = stmpe_keypad_probe,
 393         .remove         = stmpe_keypad_remove,
 394 };
 395 module_platform_driver(stmpe_keypad_driver);
 396
 397 MODULE_LICENSE("GPL v2");
 398 MODULE_DESCRIPTION("STMPExxxx keypad driver");
 399 MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");