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/slab.h>
  10 #include <linux/input.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/input/matrix_keypad.h>
  14 #include <linux/mfd/stmpe.h>
  15
  16 /* These are at the same addresses in all STMPE variants */
  17 #define STMPE_KPC_COL                   0x60
  18 #define STMPE_KPC_ROW_MSB               0x61
  19 #define STMPE_KPC_ROW_LSB               0x62
  20 #define STMPE_KPC_CTRL_MSB              0x63
  21 #define STMPE_KPC_CTRL_LSB              0x64
  22 #define STMPE_KPC_COMBI_KEY_0           0x65
  23 #define STMPE_KPC_COMBI_KEY_1           0x66
  24 #define STMPE_KPC_COMBI_KEY_2           0x67
  25 #define STMPE_KPC_DATA_BYTE0            0x68
  26 #define STMPE_KPC_DATA_BYTE1            0x69
  27 #define STMPE_KPC_DATA_BYTE2            0x6a
  28 #define STMPE_KPC_DATA_BYTE3            0x6b
  29 #define STMPE_KPC_DATA_BYTE4            0x6c
  30
  31 #define STMPE_KPC_CTRL_LSB_SCAN         (0x1 << 0)
  32 #define STMPE_KPC_CTRL_LSB_DEBOUNCE     (0x7f << 1)
  33 #define STMPE_KPC_CTRL_MSB_SCAN_COUNT   (0xf << 4)
  34
  35 #define STMPE_KPC_ROW_MSB_ROWS          0xff
  36
  37 #define STMPE_KPC_DATA_UP               (0x1 << 7)
  38 #define STMPE_KPC_DATA_ROW              (0xf << 3)
  39 #define STMPE_KPC_DATA_COL              (0x7 << 0)
  40 #define STMPE_KPC_DATA_NOKEY_MASK       0x78
  41
  42 #define STMPE_KEYPAD_MAX_DEBOUNCE       127
  43 #define STMPE_KEYPAD_MAX_SCAN_COUNT     15
  44
  45 #define STMPE_KEYPAD_MAX_ROWS           8
  46 #define STMPE_KEYPAD_MAX_COLS           8
  47 #define STMPE_KEYPAD_ROW_SHIFT          3
  48 #define STMPE_KEYPAD_KEYMAP_SIZE        \
  49         (STMPE_KEYPAD_MAX_ROWS * STMPE_KEYPAD_MAX_COLS)
  50
  51 /**
  52  * struct stmpe_keypad_variant - model-specific attributes
  53  * @auto_increment: whether the KPC_DATA_BYTE register address
  54  *                  auto-increments on multiple read
  55  * @num_data: number of data bytes
  56  * @num_normal_data: number of normal keys' data bytes
  57  * @max_cols: maximum number of columns supported
  58  * @max_rows: maximum number of rows supported
  59  * @col_gpios: bitmask of gpios which can be used for columns
  60  * @row_gpios: bitmask of gpios which can be used for rows
  61  */
  62 struct stmpe_keypad_variant {
  63         bool            auto_increment;
  64         int             num_data;
  65         int             num_normal_data;
  66         int             max_cols;
  67         int             max_rows;
  68         unsigned int    col_gpios;
  69         unsigned int    row_gpios;
  70 };
  71
  72 static const struct stmpe_keypad_variant stmpe_keypad_variants[] = {
  73         [STMPE1601] = {
  74                 .auto_increment         = true,
  75                 .num_data               = 5,
  76                 .num_normal_data        = 3,
  77                 .max_cols               = 8,
  78                 .max_rows               = 8,
  79                 .col_gpios              = 0x000ff,      /* GPIO 0 - 7 */
  80                 .row_gpios              = 0x0ff00,      /* GPIO 8 - 15 */
  81         },
  82         [STMPE2401] = {
  83                 .auto_increment         = false,
  84                 .num_data               = 3,
  85                 .num_normal_data        = 2,
  86                 .max_cols               = 8,
  87                 .max_rows               = 12,
  88                 .col_gpios              = 0x0000ff,     /* GPIO 0 - 7*/
  89                 .row_gpios              = 0x1f7f00,     /* GPIO 8-14, 16-20 */
  90         },
  91         [STMPE2403] = {
  92                 .auto_increment         = true,
  93                 .num_data               = 5,
  94                 .num_normal_data        = 3,
  95                 .max_cols               = 8,
  96                 .max_rows               = 12,
  97                 .col_gpios              = 0x0000ff,     /* GPIO 0 - 7*/
  98                 .row_gpios              = 0x1fef00,     /* GPIO 8-14, 16-20 */
  99         },
 100 };
 101
 102 struct stmpe_keypad {
 103         struct stmpe *stmpe;
 104         struct input_dev *input;
 105         const struct stmpe_keypad_variant *variant;
 106         const struct stmpe_keypad_platform_data *plat;
 107
 108         unsigned int rows;
 109         unsigned int cols;
 110
 111         unsigned short keymap[STMPE_KEYPAD_KEYMAP_SIZE];
 112 };
 113
 114 static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
 115 {
 116         const struct stmpe_keypad_variant *variant = keypad->variant;
 117         struct stmpe *stmpe = keypad->stmpe;
 118         int ret;
 119         int i;
 120
 121         if (variant->auto_increment)
 122                 return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
 123                                         variant->num_data, data);
 124
 125         for (i = 0; i < variant->num_data; i++) {
 126                 ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
 127                 if (ret < 0)
 128                         return ret;
 129
 130                 data[i] = ret;
 131         }
 132
 133         return 0;
 134 }
 135
 136 static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
 137 {
 138         struct stmpe_keypad *keypad = dev;
 139         struct input_dev *input = keypad->input;
 140         const struct stmpe_keypad_variant *variant = keypad->variant;
 141         u8 fifo[variant->num_data];
 142         int ret;
 143         int i;
 144
 145         ret = stmpe_keypad_read_data(keypad, fifo);
 146         if (ret < 0)
 147                 return IRQ_NONE;
 148
 149         for (i = 0; i < variant->num_normal_data; i++) {
 150                 u8 data = fifo[i];
 151                 int row = (data & STMPE_KPC_DATA_ROW) >> 3;
 152                 int col = data & STMPE_KPC_DATA_COL;
 153                 int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
 154                 bool up = data & STMPE_KPC_DATA_UP;
 155
 156                 if ((data & STMPE_KPC_DATA_NOKEY_MASK)
 157                         == STMPE_KPC_DATA_NOKEY_MASK)
 158                         continue;
 159
 160                 input_event(input, EV_MSC, MSC_SCAN, code);
 161                 input_report_key(input, keypad->keymap[code], !up);
 162                 input_sync(input);
 163         }
 164
 165         return IRQ_HANDLED;
 166 }
 167
 168 static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
 169 {
 170         const struct stmpe_keypad_variant *variant = keypad->variant;
 171         unsigned int col_gpios = variant->col_gpios;
 172         unsigned int row_gpios = variant->row_gpios;
 173         struct stmpe *stmpe = keypad->stmpe;
 174         unsigned int pins = 0;
 175         int i;
 176
 177         /*
 178          * Figure out which pins need to be set to the keypad alternate
 179          * function.
 180          *
 181          * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
 182          * for the keypad.
 183          *
 184          * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
 185          * for the keypad) are used on the board.
 186          */
 187
 188         for (i = 0; i < variant->max_cols; i++) {
 189                 int num = __ffs(col_gpios);
 190
 191                 if (keypad->cols & (1 << i))
 192                         pins |= 1 << num;
 193
 194                 col_gpios &= ~(1 << num);
 195         }
 196
 197         for (i = 0; i < variant->max_rows; i++) {
 198                 int num = __ffs(row_gpios);
 199
 200                 if (keypad->rows & (1 << i))
 201                         pins |= 1 << num;
 202
 203                 row_gpios &= ~(1 << num);
 204         }
 205
 206         return stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD);
 207 }
 208
 209 static int stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
 210 {
 211         const struct stmpe_keypad_platform_data *plat = keypad->plat;
 212         const struct stmpe_keypad_variant *variant = keypad->variant;
 213         struct stmpe *stmpe = keypad->stmpe;
 214         int ret;
 215
 216         if (plat->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
 217                 return -EINVAL;
 218
 219         if (plat->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
 220                 return -EINVAL;
 221
 222         ret = stmpe_enable(stmpe, STMPE_BLOCK_KEYPAD);
 223         if (ret < 0)
 224                 return ret;
 225
 226         ret = stmpe_keypad_altfunc_init(keypad);
 227         if (ret < 0)
 228                 return ret;
 229
 230         ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, keypad->cols);
 231         if (ret < 0)
 232                 return ret;
 233
 234         ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, keypad->rows);
 235         if (ret < 0)
 236                 return ret;
 237
 238         if (variant->max_rows > 8) {
 239                 ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
 240                                      STMPE_KPC_ROW_MSB_ROWS,
 241                                      keypad->rows >> 8);
 242                 if (ret < 0)
 243                         return ret;
 244         }
 245
 246         ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
 247                              STMPE_KPC_CTRL_MSB_SCAN_COUNT,
 248                              plat->scan_count << 4);
 249         if (ret < 0)
 250                 return ret;
 251
 252         return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
 253                               STMPE_KPC_CTRL_LSB_SCAN |
 254                               STMPE_KPC_CTRL_LSB_DEBOUNCE,
 255                               STMPE_KPC_CTRL_LSB_SCAN |
 256                               (plat->debounce_ms << 1));
 257 }
 258
 259 static void stmpe_keypad_fill_used_pins(struct stmpe_keypad *keypad)
 260 {
 261         int row, col;
 262
 263         for (row = 0; row < STMPE_KEYPAD_MAX_ROWS; row++) {
 264                 for (col = 0; col < STMPE_KEYPAD_MAX_COLS; col++) {
 265                         int code = MATRIX_SCAN_CODE(row, col,
 266                                                 STMPE_KEYPAD_ROW_SHIFT);
 267                         if (keypad->keymap[code] != KEY_RESERVED) {
 268                                 keypad->rows |= 1 << row;
 269                                 keypad->cols |= 1 << col;
 270                         }
 271                 }
 272         }
 273 }
 274
 275 #ifdef CONFIG_OF
 276 static const struct stmpe_keypad_platform_data *
 277 stmpe_keypad_of_probe(struct device *dev)
 278 {
 279         struct device_node *np = dev->of_node;
 280         struct stmpe_keypad_platform_data *plat;
 281
 282         if (!np)
 283                 return ERR_PTR(-ENODEV);
 284
 285         plat = devm_kzalloc(dev, sizeof(*plat), GFP_KERNEL);
 286         if (!plat)
 287                 return ERR_PTR(-ENOMEM);
 288
 289         of_property_read_u32(np, "debounce-interval", &plat->debounce_ms);
 290         of_property_read_u32(np, "st,scan-count", &plat->scan_count);
 291
 292         plat->no_autorepeat = of_property_read_bool(np, "st,no-autorepeat");
 293
 294         return plat;
 295 }
 296 #else
 297 static inline const struct stmpe_keypad_platform_data *
 298 stmpe_keypad_of_probe(struct device *dev)
 299 {
 300         return ERR_PTR(-EINVAL);
 301 }
 302 #endif
 303
 304 static int stmpe_keypad_probe(struct platform_device *pdev)
 305 {
 306         struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
 307         const struct stmpe_keypad_platform_data *plat;
 308         struct stmpe_keypad *keypad;
 309         struct input_dev *input;
 310         int error;
 311         int irq;
 312
 313         plat = stmpe->pdata->keypad;
 314         if (!plat) {
 315                 plat = stmpe_keypad_of_probe(&pdev->dev);
 316                 if (IS_ERR(plat))
 317                         return PTR_ERR(plat);
 318         }
 319
 320         irq = platform_get_irq(pdev, 0);
 321         if (irq < 0)
 322                 return irq;
 323
 324         keypad = devm_kzalloc(&pdev->dev, sizeof(struct stmpe_keypad),
 325                               GFP_KERNEL);
 326         if (!keypad)
 327                 return -ENOMEM;
 328
 329         input = devm_input_allocate_device(&pdev->dev);
 330         if (!input)
 331                 return -ENOMEM;
 332
 333         input->name = "STMPE keypad";
 334         input->id.bustype = BUS_I2C;
 335         input->dev.parent = &pdev->dev;
 336
 337         error = matrix_keypad_build_keymap(plat->keymap_data, NULL,
 338                                            STMPE_KEYPAD_MAX_ROWS,
 339                                            STMPE_KEYPAD_MAX_COLS,
 340                                            keypad->keymap, input);
 341         if (error)
 342                 return error;
 343
 344         input_set_capability(input, EV_MSC, MSC_SCAN);
 345         if (!plat->no_autorepeat)
 346                 __set_bit(EV_REP, input->evbit);
 347
 348         stmpe_keypad_fill_used_pins(keypad);
 349
 350         keypad->stmpe = stmpe;
 351         keypad->plat = plat;
 352         keypad->input = input;
 353         keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
 354
 355         error = stmpe_keypad_chip_init(keypad);
 356         if (error < 0)
 357                 return error;
 358
 359         error = devm_request_threaded_irq(&pdev->dev, irq,
 360                                           NULL, stmpe_keypad_irq,
 361                                           IRQF_ONESHOT, "stmpe-keypad", keypad);
 362         if (error) {
 363                 dev_err(&pdev->dev, "unable to get irq: %d\n", error);
 364                 return error;
 365         }
 366
 367         error = input_register_device(input);
 368         if (error) {
 369                 dev_err(&pdev->dev,
 370                         "unable to register input device: %d\n", error);
 371                 return error;
 372         }
 373
 374         platform_set_drvdata(pdev, keypad);
 375
 376         return 0;
 377 }
 378
 379 static int stmpe_keypad_remove(struct platform_device *pdev)
 380 {
 381         struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
 382
 383         stmpe_disable(keypad->stmpe, STMPE_BLOCK_KEYPAD);
 384
 385         return 0;
 386 }
 387
 388 static struct platform_driver stmpe_keypad_driver = {
 389         .driver.name    = "stmpe-keypad",
 390         .driver.owner   = THIS_MODULE,
 391         .probe          = stmpe_keypad_probe,
 392         .remove         = stmpe_keypad_remove,
 393 };
 394 module_platform_driver(stmpe_keypad_driver);
 395
 396 MODULE_LICENSE("GPL v2");
 397 MODULE_DESCRIPTION("STMPExxxx keypad driver");
 398 MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");