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