drivers/input/keyboard/nomadik-ske-keypad.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2010
   3  *
   4  * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
   5  * Author: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson
   6  *
   7  * License terms:GNU General Public License (GPL) version 2
   8  *
   9  * Keypad controller driver for the SKE (Scroll Key Encoder) module used in
  10  * the Nomadik 8815 and Ux500 platforms.
  11  */
  12
  13 #include <linux/platform_device.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/io.h>
  17 #include <linux/delay.h>
  18 #include <linux/input.h>
  19 #include <linux/slab.h>
  20 #include <linux/clk.h>
  21 #include <linux/module.h>
  22
  23 #include <linux/platform_data/keypad-nomadik-ske.h>
  24
  25 /* SKE_CR bits */
  26 #define SKE_KPMLT       (0x1 << 6)
  27 #define SKE_KPCN        (0x7 << 3)
  28 #define SKE_KPASEN      (0x1 << 2)
  29 #define SKE_KPASON      (0x1 << 7)
  30
  31 /* SKE_IMSC bits */
  32 #define SKE_KPIMA       (0x1 << 2)
  33
  34 /* SKE_ICR bits */
  35 #define SKE_KPICS       (0x1 << 3)
  36 #define SKE_KPICA       (0x1 << 2)
  37
  38 /* SKE_RIS bits */
  39 #define SKE_KPRISA      (0x1 << 2)
  40
  41 #define SKE_KEYPAD_ROW_SHIFT    3
  42 #define SKE_KPD_NUM_ROWS        8
  43 #define SKE_KPD_NUM_COLS        8
  44
  45 /* keypad auto scan registers */
  46 #define SKE_ASR0        0x20
  47 #define SKE_ASR1        0x24
  48 #define SKE_ASR2        0x28
  49 #define SKE_ASR3        0x2C
  50
  51 #define SKE_NUM_ASRX_REGISTERS  (4)
  52 #define KEY_PRESSED_DELAY       10
  53
  54 /**
  55  * struct ske_keypad  - data structure used by keypad driver
  56  * @irq:        irq no
  57  * @reg_base:   ske registers base address
  58  * @input:      pointer to input device object
  59  * @board:      keypad platform device
  60  * @keymap:     matrix scan code table for keycodes
  61  * @clk:        clock structure pointer
  62  */
  63 struct ske_keypad {
  64         int irq;
  65         void __iomem *reg_base;
  66         struct input_dev *input;
  67         const struct ske_keypad_platform_data *board;
  68         unsigned short keymap[SKE_KPD_NUM_ROWS * SKE_KPD_NUM_COLS];
  69         struct clk *clk;
  70         struct clk *pclk;
  71         spinlock_t ske_keypad_lock;
  72 };
  73
  74 static void ske_keypad_set_bits(struct ske_keypad *keypad, u16 addr,
  75                 u8 mask, u8 data)
  76 {
  77         u32 ret;
  78
  79         spin_lock(&keypad->ske_keypad_lock);
  80
  81         ret = readl(keypad->reg_base + addr);
  82         ret &= ~mask;
  83         ret |= data;
  84         writel(ret, keypad->reg_base + addr);
  85
  86         spin_unlock(&keypad->ske_keypad_lock);
  87 }
  88
  89 /*
  90  * ske_keypad_chip_init: init keypad controller configuration
  91  *
  92  * Enable Multi key press detection, auto scan mode
  93  */
  94 static int __init ske_keypad_chip_init(struct ske_keypad *keypad)
  95 {
  96         u32 value;
  97         int timeout = keypad->board->debounce_ms;
  98
  99         /* check SKE_RIS to be 0 */
 100         while ((readl(keypad->reg_base + SKE_RIS) != 0x00000000) && timeout--)
 101                 cpu_relax();
 102
 103         if (!timeout)
 104                 return -EINVAL;
 105
 106         /*
 107          * set debounce value
 108          * keypad dbounce is configured in DBCR[15:8]
 109          * dbounce value in steps of 32/32.768 ms
 110          */
 111         spin_lock(&keypad->ske_keypad_lock);
 112         value = readl(keypad->reg_base + SKE_DBCR);
 113         value = value & 0xff;
 114         value |= ((keypad->board->debounce_ms * 32000)/32768) << 8;
 115         writel(value, keypad->reg_base + SKE_DBCR);
 116         spin_unlock(&keypad->ske_keypad_lock);
 117
 118         /* enable multi key detection */
 119         ske_keypad_set_bits(keypad, SKE_CR, 0x0, SKE_KPMLT);
 120
 121         /*
 122          * set up the number of columns
 123          * KPCN[5:3] defines no. of keypad columns to be auto scanned
 124          */
 125         value = (keypad->board->kcol - 1) << 3;
 126         ske_keypad_set_bits(keypad, SKE_CR, SKE_KPCN, value);
 127
 128         /* clear keypad interrupt for auto(and pending SW) scans */
 129         ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA | SKE_KPICS);
 130
 131         /* un-mask keypad interrupts */
 132         ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 133
 134         /* enable automatic scan */
 135         ske_keypad_set_bits(keypad, SKE_CR, 0x0, SKE_KPASEN);
 136
 137         return 0;
 138 }
 139
 140 static void ske_keypad_report(struct ske_keypad *keypad, u8 status, int col)
 141 {
 142         int row = 0, code, pos;
 143         struct input_dev *input = keypad->input;
 144         u32 ske_ris;
 145         int key_pressed;
 146         int num_of_rows;
 147
 148         /* find out the row */
 149         num_of_rows = hweight8(status);
 150         do {
 151                 pos = __ffs(status);
 152                 row = pos;
 153                 status &= ~(1 << pos);
 154
 155                 code = MATRIX_SCAN_CODE(row, col, SKE_KEYPAD_ROW_SHIFT);
 156                 ske_ris = readl(keypad->reg_base + SKE_RIS);
 157                 key_pressed = ske_ris & SKE_KPRISA;
 158
 159                 input_event(input, EV_MSC, MSC_SCAN, code);
 160                 input_report_key(input, keypad->keymap[code], key_pressed);
 161                 input_sync(input);
 162                 num_of_rows--;
 163         } while (num_of_rows);
 164 }
 165
 166 static void ske_keypad_read_data(struct ske_keypad *keypad)
 167 {
 168         u8 status;
 169         int col = 0;
 170         int ske_asr, i;
 171
 172         /*
 173          * Read the auto scan registers
 174          *
 175          * Each SKE_ASRx (x=0 to x=3) contains two row values.
 176          * lower byte contains row value for column 2*x,
 177          * upper byte contains row value for column 2*x + 1
 178          */
 179         for (i = 0; i < SKE_NUM_ASRX_REGISTERS; i++) {
 180                 ske_asr = readl(keypad->reg_base + SKE_ASR0 + (4 * i));
 181                 if (!ske_asr)
 182                         continue;
 183
 184                 /* now that ASRx is zero, find out the coloumn x and row y */
 185                 status = ske_asr & 0xff;
 186                 if (status) {
 187                         col = i * 2;
 188                         ske_keypad_report(keypad, status, col);
 189                 }
 190                 status = (ske_asr & 0xff00) >> 8;
 191                 if (status) {
 192                         col = (i * 2) + 1;
 193                         ske_keypad_report(keypad, status, col);
 194                 }
 195         }
 196 }
 197
 198 static irqreturn_t ske_keypad_irq(int irq, void *dev_id)
 199 {
 200         struct ske_keypad *keypad = dev_id;
 201         int timeout = keypad->board->debounce_ms;
 202
 203         /* disable auto scan interrupt; mask the interrupt generated */
 204         ske_keypad_set_bits(keypad, SKE_IMSC, ~SKE_KPIMA, 0x0);
 205         ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA);
 206
 207         while ((readl(keypad->reg_base + SKE_CR) & SKE_KPASON) && --timeout)
 208                 cpu_relax();
 209
 210         /* SKEx registers are stable and can be read */
 211         ske_keypad_read_data(keypad);
 212
 213         /* wait until raw interrupt is clear */
 214         while ((readl(keypad->reg_base + SKE_RIS)) && --timeout)
 215                 msleep(KEY_PRESSED_DELAY);
 216
 217         /* enable auto scan interrupts */
 218         ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 219
 220         return IRQ_HANDLED;
 221 }
 222
 223 static int __init ske_keypad_probe(struct platform_device *pdev)
 224 {
 225         const struct ske_keypad_platform_data *plat =
 226                         dev_get_platdata(&pdev->dev);
 227         struct ske_keypad *keypad;
 228         struct input_dev *input;
 229         struct resource *res;
 230         int irq;
 231         int error;
 232
 233         if (!plat) {
 234                 dev_err(&pdev->dev, "invalid keypad platform data\n");
 235                 return -EINVAL;
 236         }
 237
 238         irq = platform_get_irq(pdev, 0);
 239         if (irq < 0) {
 240                 dev_err(&pdev->dev, "failed to get keypad irq\n");
 241                 return -EINVAL;
 242         }
 243
 244         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 245         if (!res) {
 246                 dev_err(&pdev->dev, "missing platform resources\n");
 247                 return -EINVAL;
 248         }
 249
 250         keypad = kzalloc(sizeof(struct ske_keypad), GFP_KERNEL);
 251         input = input_allocate_device();
 252         if (!keypad || !input) {
 253                 dev_err(&pdev->dev, "failed to allocate keypad memory\n");
 254                 error = -ENOMEM;
 255                 goto err_free_mem;
 256         }
 257
 258         keypad->irq = irq;
 259         keypad->board = plat;
 260         keypad->input = input;
 261         spin_lock_init(&keypad->ske_keypad_lock);
 262
 263         if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
 264                 dev_err(&pdev->dev, "failed to request I/O memory\n");
 265                 error = -EBUSY;
 266                 goto err_free_mem;
 267         }
 268
 269         keypad->reg_base = ioremap(res->start, resource_size(res));
 270         if (!keypad->reg_base) {
 271                 dev_err(&pdev->dev, "failed to remap I/O memory\n");
 272                 error = -ENXIO;
 273                 goto err_free_mem_region;
 274         }
 275
 276         keypad->pclk = clk_get(&pdev->dev, "apb_pclk");
 277         if (IS_ERR(keypad->pclk)) {
 278                 dev_err(&pdev->dev, "failed to get pclk\n");
 279                 error = PTR_ERR(keypad->pclk);
 280                 goto err_iounmap;
 281         }
 282
 283         keypad->clk = clk_get(&pdev->dev, NULL);
 284         if (IS_ERR(keypad->clk)) {
 285                 dev_err(&pdev->dev, "failed to get clk\n");
 286                 error = PTR_ERR(keypad->clk);
 287                 goto err_pclk;
 288         }
 289
 290         input->id.bustype = BUS_HOST;
 291         input->name = "ux500-ske-keypad";
 292         input->dev.parent = &pdev->dev;
 293
 294         error = matrix_keypad_build_keymap(plat->keymap_data, NULL,
 295                                            SKE_KPD_NUM_ROWS, SKE_KPD_NUM_COLS,
 296                                            keypad->keymap, input);
 297         if (error) {
 298                 dev_err(&pdev->dev, "Failed to build keymap\n");
 299                 goto err_clk;
 300         }
 301
 302         input_set_capability(input, EV_MSC, MSC_SCAN);
 303         if (!plat->no_autorepeat)
 304                 __set_bit(EV_REP, input->evbit);
 305
 306         error = clk_prepare_enable(keypad->pclk);
 307         if (error) {
 308                 dev_err(&pdev->dev, "Failed to prepare/enable pclk\n");
 309                 goto err_clk;
 310         }
 311
 312         error = clk_prepare_enable(keypad->clk);
 313         if (error) {
 314                 dev_err(&pdev->dev, "Failed to prepare/enable clk\n");
 315                 goto err_pclk_disable;
 316         }
 317
 318
 319         /* go through board initialization helpers */
 320         if (keypad->board->init)
 321                 keypad->board->init();
 322
 323         error = ske_keypad_chip_init(keypad);
 324         if (error) {
 325                 dev_err(&pdev->dev, "unable to init keypad hardware\n");
 326                 goto err_clk_disable;
 327         }
 328
 329         error = request_threaded_irq(keypad->irq, NULL, ske_keypad_irq,
 330                                      IRQF_ONESHOT, "ske-keypad", keypad);
 331         if (error) {
 332                 dev_err(&pdev->dev, "allocate irq %d failed\n", keypad->irq);
 333                 goto err_clk_disable;
 334         }
 335
 336         error = input_register_device(input);
 337         if (error) {
 338                 dev_err(&pdev->dev,
 339                                 "unable to register input device: %d\n", error);
 340                 goto err_free_irq;
 341         }
 342
 343         if (plat->wakeup_enable)
 344                 device_init_wakeup(&pdev->dev, true);
 345
 346         platform_set_drvdata(pdev, keypad);
 347
 348         return 0;
 349
 350 err_free_irq:
 351         free_irq(keypad->irq, keypad);
 352 err_clk_disable:
 353         clk_disable_unprepare(keypad->clk);
 354 err_pclk_disable:
 355         clk_disable_unprepare(keypad->pclk);
 356 err_clk:
 357         clk_put(keypad->clk);
 358 err_pclk:
 359         clk_put(keypad->pclk);
 360 err_iounmap:
 361         iounmap(keypad->reg_base);
 362 err_free_mem_region:
 363         release_mem_region(res->start, resource_size(res));
 364 err_free_mem:
 365         input_free_device(input);
 366         kfree(keypad);
 367         return error;
 368 }
 369
 370 static int ske_keypad_remove(struct platform_device *pdev)
 371 {
 372         struct ske_keypad *keypad = platform_get_drvdata(pdev);
 373         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 374
 375         free_irq(keypad->irq, keypad);
 376
 377         input_unregister_device(keypad->input);
 378
 379         clk_disable_unprepare(keypad->clk);
 380         clk_put(keypad->clk);
 381
 382         if (keypad->board->exit)
 383                 keypad->board->exit();
 384
 385         iounmap(keypad->reg_base);
 386         release_mem_region(res->start, resource_size(res));
 387         kfree(keypad);
 388
 389         return 0;
 390 }
 391
 392 #ifdef CONFIG_PM_SLEEP
 393 static int ske_keypad_suspend(struct device *dev)
 394 {
 395         struct platform_device *pdev = to_platform_device(dev);
 396         struct ske_keypad *keypad = platform_get_drvdata(pdev);
 397         int irq = platform_get_irq(pdev, 0);
 398
 399         if (device_may_wakeup(dev))
 400                 enable_irq_wake(irq);
 401         else
 402                 ske_keypad_set_bits(keypad, SKE_IMSC, ~SKE_KPIMA, 0x0);
 403
 404         return 0;
 405 }
 406
 407 static int ske_keypad_resume(struct device *dev)
 408 {
 409         struct platform_device *pdev = to_platform_device(dev);
 410         struct ske_keypad *keypad = platform_get_drvdata(pdev);
 411         int irq = platform_get_irq(pdev, 0);
 412
 413         if (device_may_wakeup(dev))
 414                 disable_irq_wake(irq);
 415         else
 416                 ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 417
 418         return 0;
 419 }
 420 #endif
 421
 422 static SIMPLE_DEV_PM_OPS(ske_keypad_dev_pm_ops,
 423                          ske_keypad_suspend, ske_keypad_resume);
 424
 425 static struct platform_driver ske_keypad_driver = {
 426         .driver = {
 427                 .name = "nmk-ske-keypad",
 428                 .pm = &ske_keypad_dev_pm_ops,
 429         },
 430         .remove = ske_keypad_remove,
 431 };
 432
 433 module_platform_driver_probe(ske_keypad_driver, ske_keypad_probe);
 434
 435 MODULE_LICENSE("GPL v2");
 436 MODULE_AUTHOR("Naveen Kumar <naveen.gaddipati@stericsson.com> / Sundar Iyer <sundar.iyer@stericsson.com>");
 437 MODULE_DESCRIPTION("Nomadik Scroll-Key-Encoder Keypad Driver");
 438 MODULE_ALIAS("platform:nomadik-ske-keypad");