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_MAX_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              = 0x1fef00,     /* 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 /**
 103  * struct stmpe_keypad - STMPE keypad state container
 104  * @stmpe: pointer to parent STMPE device
 105  * @input: spawned input device
 106  * @variant: STMPE variant
 107  * @debounce_ms: debounce interval, in ms.  Maximum is
 108  *               %STMPE_KEYPAD_MAX_DEBOUNCE.
 109  * @scan_count: number of key scanning cycles to confirm key data.
 110  *              Maximum is %STMPE_KEYPAD_MAX_SCAN_COUNT.
 111  * @no_autorepeat: disable key autorepeat
 112  * @rows: bitmask for the rows
 113  * @cols: bitmask for the columns
 114  * @keymap: the keymap
 115  */
 116 struct stmpe_keypad {
 117         struct stmpe *stmpe;
 118         struct input_dev *input;
 119         const struct stmpe_keypad_variant *variant;
 120         unsigned int debounce_ms;
 121         unsigned int scan_count;
 122         bool no_autorepeat;
 123         unsigned int rows;
 124         unsigned int cols;
 125         unsigned short keymap[STMPE_KEYPAD_KEYMAP_MAX_SIZE];
 126 };
 127
 128 static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
 129 {
 130         const struct stmpe_keypad_variant *variant = keypad->variant;
 131         struct stmpe *stmpe = keypad->stmpe;
 132         int ret;
 133         int i;
 134
 135         if (variant->auto_increment)
 136                 return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
 137                                         variant->num_data, data);
 138
 139         for (i = 0; i < variant->num_data; i++) {
 140                 ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
 141                 if (ret < 0)
 142                         return ret;
 143
 144                 data[i] = ret;
 145         }
 146
 147         return 0;
 148 }
 149
 150 static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
 151 {
 152         struct stmpe_keypad *keypad = dev;
 153         struct input_dev *input = keypad->input;
 154         const struct stmpe_keypad_variant *variant = keypad->variant;
 155         u8 fifo[variant->num_data];
 156         int ret;
 157         int i;
 158
 159         ret = stmpe_keypad_read_data(keypad, fifo);
 160         if (ret < 0)
 161                 return IRQ_NONE;
 162
 163         for (i = 0; i < variant->num_normal_data; i++) {
 164                 u8 data = fifo[i];
 165                 int row = (data & STMPE_KPC_DATA_ROW) >> 3;
 166                 int col = data & STMPE_KPC_DATA_COL;
 167                 int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
 168                 bool up = data & STMPE_KPC_DATA_UP;
 169
 170                 if ((data & STMPE_KPC_DATA_NOKEY_MASK)
 171                         == STMPE_KPC_DATA_NOKEY_MASK)
 172                         continue;
 173
 174                 input_event(input, EV_MSC, MSC_SCAN, code);
 175                 input_report_key(input, keypad->keymap[code], !up);
 176                 input_sync(input);
 177         }
 178
 179         return IRQ_HANDLED;
 180 }
 181
 182 static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
 183 {
 184         const struct stmpe_keypad_variant *variant = keypad->variant;
 185         unsigned int col_gpios = variant->col_gpios;
 186         unsigned int row_gpios = variant->row_gpios;
 187         struct stmpe *stmpe = keypad->stmpe;
 188         unsigned int pins = 0;
 189         int i;
 190
 191         /*
 192          * Figure out which pins need to be set to the keypad alternate
 193          * function.
 194          *
 195          * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
 196          * for the keypad.
 197          *
 198          * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
 199          * for the keypad) are used on the board.
 200          */
 201
 202         for (i = 0; i < variant->max_cols; i++) {
 203                 int num = __ffs(col_gpios);
 204
 205                 if (keypad->cols & (1 << i))
 206                         pins |= 1 << num;
 207
 208                 col_gpios &= ~(1 << num);
 209         }
 210
 211         for (i = 0; i < variant->max_rows; i++) {
 212                 int num = __ffs(row_gpios);
 213
 214                 if (keypad->rows & (1 << i))
 215                         pins |= 1 << num;
 216
 217                 row_gpios &= ~(1 << num);
 218         }
 219
 220         return stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD);
 221 }
 222
 223 static int stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
 224 {
 225         const struct stmpe_keypad_variant *variant = keypad->variant;
 226         struct stmpe *stmpe = keypad->stmpe;
 227         int ret;
 228
 229         if (keypad->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
 230                 return -EINVAL;
 231
 232         if (keypad->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
 233                 return -EINVAL;
 234
 235         ret = stmpe_enable(stmpe, STMPE_BLOCK_KEYPAD);
 236         if (ret < 0)
 237                 return ret;
 238
 239         ret = stmpe_keypad_altfunc_init(keypad);
 240         if (ret < 0)
 241                 return ret;
 242
 243         ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, keypad->cols);
 244         if (ret < 0)
 245                 return ret;
 246
 247         ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, keypad->rows);
 248         if (ret < 0)
 249                 return ret;
 250
 251         if (variant->max_rows > 8) {
 252                 ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
 253                                      STMPE_KPC_ROW_MSB_ROWS,
 254                                      keypad->rows >> 8);
 255                 if (ret < 0)
 256                         return ret;
 257         }
 258
 259         ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
 260                              STMPE_KPC_CTRL_MSB_SCAN_COUNT,
 261                              keypad->scan_count << 4);
 262         if (ret < 0)
 263                 return ret;
 264
 265         return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
 266                               STMPE_KPC_CTRL_LSB_SCAN |
 267                               STMPE_KPC_CTRL_LSB_DEBOUNCE,
 268                               STMPE_KPC_CTRL_LSB_SCAN |
 269                               (keypad->debounce_ms << 1));
 270 }
 271
 272 static void stmpe_keypad_fill_used_pins(struct stmpe_keypad *keypad,
 273                                         u32 used_rows, u32 used_cols)
 274 {
 275         int row, col;
 276
 277         for (row = 0; row < used_rows; row++) {
 278                 for (col = 0; col < used_cols; col++) {
 279                         int code = MATRIX_SCAN_CODE(row, col,
 280                                                     STMPE_KEYPAD_ROW_SHIFT);
 281                         if (keypad->keymap[code] != KEY_RESERVED) {
 282                                 keypad->rows |= 1 << row;
 283                                 keypad->cols |= 1 << col;
 284                         }
 285                 }
 286         }
 287 }
 288
 289 static int stmpe_keypad_probe(struct platform_device *pdev)
 290 {
 291         struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
 292         struct device_node *np = pdev->dev.of_node;
 293         struct stmpe_keypad *keypad;
 294         struct input_dev *input;
 295         u32 rows;
 296         u32 cols;
 297         int error;
 298         int irq;
 299
 300         irq = platform_get_irq(pdev, 0);
 301         if (irq < 0)
 302                 return irq;
 303
 304         keypad = devm_kzalloc(&pdev->dev, sizeof(struct stmpe_keypad),
 305                               GFP_KERNEL);
 306         if (!keypad)
 307                 return -ENOMEM;
 308
 309         keypad->stmpe = stmpe;
 310         keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
 311
 312         of_property_read_u32(np, "debounce-interval", &keypad->debounce_ms);
 313         of_property_read_u32(np, "st,scan-count", &keypad->scan_count);
 314         keypad->no_autorepeat = of_property_read_bool(np, "st,no-autorepeat");
 315
 316         input = devm_input_allocate_device(&pdev->dev);
 317         if (!input)
 318                 return -ENOMEM;
 319
 320         input->name = "STMPE keypad";
 321         input->id.bustype = BUS_I2C;
 322         input->dev.parent = &pdev->dev;
 323
 324         error = matrix_keypad_parse_of_params(&pdev->dev, &rows, &cols);
 325         if (error)
 326                 return error;
 327
 328         error = matrix_keypad_build_keymap(NULL, NULL, rows, cols,
 329                                            keypad->keymap, input);
 330         if (error)
 331                 return error;
 332
 333         input_set_capability(input, EV_MSC, MSC_SCAN);
 334         if (!keypad->no_autorepeat)
 335                 __set_bit(EV_REP, input->evbit);
 336
 337         stmpe_keypad_fill_used_pins(keypad, rows, cols);
 338
 339         keypad->input = input;
 340
 341         error = stmpe_keypad_chip_init(keypad);
 342         if (error < 0)
 343                 return error;
 344
 345         error = devm_request_threaded_irq(&pdev->dev, irq,
 346                                           NULL, stmpe_keypad_irq,
 347                                           IRQF_ONESHOT, "stmpe-keypad", keypad);
 348         if (error) {
 349                 dev_err(&pdev->dev, "unable to get irq: %d\n", error);
 350                 return error;
 351         }
 352
 353         error = input_register_device(input);
 354         if (error) {
 355                 dev_err(&pdev->dev,
 356                         "unable to register input device: %d\n", error);
 357                 return error;
 358         }
 359
 360         platform_set_drvdata(pdev, keypad);
 361
 362         return 0;
 363 }
 364
 365 static int stmpe_keypad_remove(struct platform_device *pdev)
 366 {
 367         struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
 368
 369         stmpe_disable(keypad->stmpe, STMPE_BLOCK_KEYPAD);
 370
 371         return 0;
 372 }
 373
 374 static struct platform_driver stmpe_keypad_driver = {
 375         .driver.name    = "stmpe-keypad",
 376         .driver.owner   = THIS_MODULE,
 377         .probe          = stmpe_keypad_probe,
 378         .remove         = stmpe_keypad_remove,
 379 };
 380 module_platform_driver(stmpe_keypad_driver);
 381
 382 MODULE_LICENSE("GPL v2");
 383 MODULE_DESCRIPTION("STMPExxxx keypad driver");
 384 MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");