drivers/input/keyboard/omap4-keypad.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * OMAP4 Keypad Driver
   4  *
   5  * Copyright (C) 2010 Texas Instruments
   6  *
   7  * Author: Abraham Arce <[email protected]>
   8  * Initial Code: Syed Rafiuddin <[email protected]>
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/errno.h>
  15 #include <linux/io.h>
  16 #include <linux/of.h>
  17 #include <linux/input.h>
  18 #include <linux/input/matrix_keypad.h>
  19 #include <linux/slab.h>
  20 #include <linux/pm_runtime.h>
  21 #include <linux/pm_wakeirq.h>
  22
  23 /* OMAP4 registers */
  24 #define OMAP4_KBD_REVISION              0x00
  25 #define OMAP4_KBD_SYSCONFIG             0x10
  26 #define OMAP4_KBD_SYSSTATUS             0x14
  27 #define OMAP4_KBD_IRQSTATUS             0x18
  28 #define OMAP4_KBD_IRQENABLE             0x1C
  29 #define OMAP4_KBD_WAKEUPENABLE          0x20
  30 #define OMAP4_KBD_PENDING               0x24
  31 #define OMAP4_KBD_CTRL                  0x28
  32 #define OMAP4_KBD_DEBOUNCINGTIME        0x2C
  33 #define OMAP4_KBD_LONGKEYTIME           0x30
  34 #define OMAP4_KBD_TIMEOUT               0x34
  35 #define OMAP4_KBD_STATEMACHINE          0x38
  36 #define OMAP4_KBD_ROWINPUTS             0x3C
  37 #define OMAP4_KBD_COLUMNOUTPUTS         0x40
  38 #define OMAP4_KBD_FULLCODE31_0          0x44
  39 #define OMAP4_KBD_FULLCODE63_32         0x48
  40
  41 /* OMAP4 bit definitions */
  42 #define OMAP4_DEF_IRQENABLE_EVENTEN     BIT(0)
  43 #define OMAP4_DEF_IRQENABLE_LONGKEY     BIT(1)
  44 #define OMAP4_DEF_WUP_EVENT_ENA         BIT(0)
  45 #define OMAP4_DEF_WUP_LONG_KEY_ENA      BIT(1)
  46 #define OMAP4_DEF_CTRL_NOSOFTMODE       BIT(1)
  47 #define OMAP4_DEF_CTRL_PTV_SHIFT        2
  48
  49 /* OMAP4 values */
  50 #define OMAP4_VAL_IRQDISABLE            0x0
  51
  52 /*
  53  * Errata i689: If a key is released for a time shorter than debounce time,
  54  * the keyboard will idle and never detect the key release. The workaround
  55  * is to use at least a 12ms debounce time. See omap5432 TRM chapter
  56  * "26.4.6.2 Keyboard Controller Timer" for more information.
  57  */
  58 #define OMAP4_KEYPAD_PTV_DIV_128        0x6
  59 #define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv)     \
  60         ((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
  61 #define OMAP4_VAL_DEBOUNCINGTIME_16MS                                   \
  62         OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)
  63 #define OMAP4_KEYPAD_AUTOIDLE_MS        50      /* Approximate measured time */
  64 #define OMAP4_KEYPAD_IDLE_CHECK_MS      (OMAP4_KEYPAD_AUTOIDLE_MS / 2)
  65
  66 enum {
  67         KBD_REVISION_OMAP4 = 0,
  68         KBD_REVISION_OMAP5,
  69 };
  70
  71 struct omap4_keypad {
  72         struct input_dev *input;
  73
  74         void __iomem *base;
  75         unsigned int irq;
  76         struct mutex lock;              /* for key scan */
  77
  78         unsigned int rows;
  79         unsigned int cols;
  80         u32 reg_offset;
  81         u32 irqreg_offset;
  82         unsigned int row_shift;
  83         bool no_autorepeat;
  84         u64 keys;
  85         unsigned short *keymap;
  86 };
  87
  88 static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
  89 {
  90         return __raw_readl(keypad_data->base +
  91                                 keypad_data->reg_offset + offset);
  92 }
  93
  94 static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
  95 {
  96         __raw_writel(value,
  97                      keypad_data->base + keypad_data->reg_offset + offset);
  98 }
  99
 100 static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
 101 {
 102         return __raw_readl(keypad_data->base +
 103                                 keypad_data->irqreg_offset + offset);
 104 }
 105
 106 static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
 107                              u32 offset, u32 value)
 108 {
 109         __raw_writel(value,
 110                      keypad_data->base + keypad_data->irqreg_offset + offset);
 111 }
 112
 113 static int omap4_keypad_report_keys(struct omap4_keypad *keypad_data,
 114                                     u64 keys, bool down)
 115 {
 116         struct input_dev *input_dev = keypad_data->input;
 117         unsigned int col, row, code;
 118         DECLARE_BITMAP(mask, 64);
 119         unsigned long bit;
 120         int events = 0;
 121
 122         bitmap_from_u64(mask, keys);
 123
 124         for_each_set_bit(bit, mask, keypad_data->rows * BITS_PER_BYTE) {
 125                 row = bit / BITS_PER_BYTE;
 126                 col = bit % BITS_PER_BYTE;
 127                 code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift);
 128
 129                 input_event(input_dev, EV_MSC, MSC_SCAN, code);
 130                 input_report_key(input_dev, keypad_data->keymap[code], down);
 131
 132                 events++;
 133         }
 134
 135         if (events)
 136                 input_sync(input_dev);
 137
 138         return events;
 139 }
 140
 141 static void omap4_keypad_scan_keys(struct omap4_keypad *keypad_data, u64 keys)
 142 {
 143         u64 changed;
 144
 145         mutex_lock(&keypad_data->lock);
 146
 147         changed = keys ^ keypad_data->keys;
 148
 149         /*
 150          * Report key up events separately and first. This matters in case we
 151          * lost key-up interrupt and just now catching up.
 152          */
 153         omap4_keypad_report_keys(keypad_data, changed & ~keys, false);
 154
 155         /* Report key down events */
 156         omap4_keypad_report_keys(keypad_data, changed & keys, true);
 157
 158         keypad_data->keys = keys;
 159
 160         mutex_unlock(&keypad_data->lock);
 161 }
 162
 163 /* Interrupt handlers */
 164 static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
 165 {
 166         struct omap4_keypad *keypad_data = dev_id;
 167
 168         if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
 169                 return IRQ_WAKE_THREAD;
 170
 171         return IRQ_NONE;
 172 }
 173
 174 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
 175 {
 176         struct omap4_keypad *keypad_data = dev_id;
 177         struct device *dev = keypad_data->input->dev.parent;
 178         u32 low, high;
 179         int error;
 180         u64 keys;
 181
 182         error = pm_runtime_resume_and_get(dev);
 183         if (error)
 184                 return IRQ_NONE;
 185
 186         low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
 187         high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
 188         keys = low | (u64)high << 32;
 189
 190         omap4_keypad_scan_keys(keypad_data, keys);
 191
 192         /* clear pending interrupts */
 193         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 194                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 195
 196         pm_runtime_mark_last_busy(dev);
 197         pm_runtime_put_autosuspend(dev);
 198
 199         return IRQ_HANDLED;
 200 }
 201
 202 static int omap4_keypad_open(struct input_dev *input)
 203 {
 204         struct omap4_keypad *keypad_data = input_get_drvdata(input);
 205         struct device *dev = input->dev.parent;
 206         int error;
 207
 208         error = pm_runtime_resume_and_get(dev);
 209         if (error)
 210                 return error;
 211
 212         disable_irq(keypad_data->irq);
 213
 214         kbd_writel(keypad_data, OMAP4_KBD_CTRL,
 215                         OMAP4_DEF_CTRL_NOSOFTMODE |
 216                         (OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
 217         kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
 218                         OMAP4_VAL_DEBOUNCINGTIME_16MS);
 219         /* clear pending interrupts */
 220         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 221                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 222         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 223                         OMAP4_DEF_IRQENABLE_EVENTEN);
 224         kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
 225                         OMAP4_DEF_WUP_EVENT_ENA);
 226
 227         enable_irq(keypad_data->irq);
 228
 229         pm_runtime_mark_last_busy(dev);
 230         pm_runtime_put_autosuspend(dev);
 231
 232         return 0;
 233 }
 234
 235 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
 236 {
 237         /* Disable interrupts and wake-up events */
 238         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 239                          OMAP4_VAL_IRQDISABLE);
 240         kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
 241
 242         /* clear pending interrupts */
 243         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 244                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 245 }
 246
 247 static void omap4_keypad_close(struct input_dev *input)
 248 {
 249         struct omap4_keypad *keypad_data = input_get_drvdata(input);
 250         struct device *dev = input->dev.parent;
 251         int error;
 252
 253         error = pm_runtime_resume_and_get(dev);
 254         if (error)
 255                 dev_err(dev, "%s: pm_runtime_resume_and_get() failed: %d\n",
 256                         __func__, error);
 257
 258         disable_irq(keypad_data->irq);
 259         omap4_keypad_stop(keypad_data);
 260         enable_irq(keypad_data->irq);
 261
 262         pm_runtime_mark_last_busy(dev);
 263         pm_runtime_put_autosuspend(dev);
 264 }
 265
 266 static int omap4_keypad_parse_dt(struct device *dev,
 267                                  struct omap4_keypad *keypad_data)
 268 {
 269         struct device_node *np = dev->of_node;
 270         int err;
 271
 272         err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
 273                                              &keypad_data->cols);
 274         if (err)
 275                 return err;
 276
 277         if (of_get_property(np, "linux,input-no-autorepeat", NULL))
 278                 keypad_data->no_autorepeat = true;
 279
 280         return 0;
 281 }
 282
 283 static int omap4_keypad_check_revision(struct device *dev,
 284                                        struct omap4_keypad *keypad_data)
 285 {
 286         unsigned int rev;
 287
 288         rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
 289         rev &= 0x03 << 30;
 290         rev >>= 30;
 291         switch (rev) {
 292         case KBD_REVISION_OMAP4:
 293                 keypad_data->reg_offset = 0x00;
 294                 keypad_data->irqreg_offset = 0x00;
 295                 break;
 296         case KBD_REVISION_OMAP5:
 297                 keypad_data->reg_offset = 0x10;
 298                 keypad_data->irqreg_offset = 0x0c;
 299                 break;
 300         default:
 301                 dev_err(dev, "Keypad reports unsupported revision %d", rev);
 302                 return -EINVAL;
 303         }
 304
 305         return 0;
 306 }
 307
 308 /*
 309  * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed".
 310  * Interrupt may not happen for key-up events. We must clear stuck
 311  * key-up events after the keyboard hardware has auto-idled.
 312  */
 313 static int __maybe_unused omap4_keypad_runtime_suspend(struct device *dev)
 314 {
 315         struct platform_device *pdev = to_platform_device(dev);
 316         struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
 317         u32 active;
 318
 319         active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE);
 320         if (active) {
 321                 pm_runtime_mark_last_busy(dev);
 322                 return -EBUSY;
 323         }
 324
 325         omap4_keypad_scan_keys(keypad_data, 0);
 326
 327         return 0;
 328 }
 329
 330 static const struct dev_pm_ops omap4_keypad_pm_ops = {
 331         SET_RUNTIME_PM_OPS(omap4_keypad_runtime_suspend, NULL, NULL)
 332 };
 333
 334 static void omap4_disable_pm(void *d)
 335 {
 336         pm_runtime_dont_use_autosuspend(d);
 337         pm_runtime_disable(d);
 338 }
 339
 340 static int omap4_keypad_probe(struct platform_device *pdev)
 341 {
 342         struct device *dev = &pdev->dev;
 343         struct omap4_keypad *keypad_data;
 344         struct input_dev *input_dev;
 345         struct resource *res;
 346         unsigned int max_keys;
 347         int irq;
 348         int error;
 349
 350         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 351         if (!res) {
 352                 dev_err(&pdev->dev, "no base address specified\n");
 353                 return -EINVAL;
 354         }
 355
 356         irq = platform_get_irq(pdev, 0);
 357         if (irq < 0)
 358                 return irq;
 359
 360         keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
 361         if (!keypad_data) {
 362                 dev_err(dev, "keypad_data memory allocation failed\n");
 363                 return -ENOMEM;
 364         }
 365
 366         keypad_data->irq = irq;
 367         mutex_init(&keypad_data->lock);
 368         platform_set_drvdata(pdev, keypad_data);
 369
 370         error = omap4_keypad_parse_dt(dev, keypad_data);
 371         if (error)
 372                 return error;
 373
 374         keypad_data->base = devm_ioremap_resource(dev, res);
 375         if (IS_ERR(keypad_data->base))
 376                 return PTR_ERR(keypad_data->base);
 377
 378         pm_runtime_use_autosuspend(dev);
 379         pm_runtime_set_autosuspend_delay(dev, OMAP4_KEYPAD_IDLE_CHECK_MS);
 380         pm_runtime_enable(dev);
 381
 382         error = devm_add_action_or_reset(dev, omap4_disable_pm, dev);
 383         if (error) {
 384                 dev_err(dev, "unable to register cleanup action\n");
 385                 return error;
 386         }
 387
 388         /*
 389          * Enable clocks for the keypad module so that we can read
 390          * revision register.
 391          */
 392         error = pm_runtime_resume_and_get(dev);
 393         if (error) {
 394                 dev_err(dev, "pm_runtime_resume_and_get() failed\n");
 395                 return error;
 396         }
 397
 398         error = omap4_keypad_check_revision(dev, keypad_data);
 399         if (!error) {
 400                 /* Ensure device does not raise interrupts */
 401                 omap4_keypad_stop(keypad_data);
 402         }
 403
 404         pm_runtime_mark_last_busy(dev);
 405         pm_runtime_put_autosuspend(dev);
 406         if (error)
 407                 return error;
 408
 409         /* input device allocation */
 410         keypad_data->input = input_dev = devm_input_allocate_device(dev);
 411         if (!input_dev)
 412                 return -ENOMEM;
 413
 414         input_dev->name = pdev->name;
 415         input_dev->id.bustype = BUS_HOST;
 416         input_dev->id.vendor = 0x0001;
 417         input_dev->id.product = 0x0001;
 418         input_dev->id.version = 0x0001;
 419
 420         input_dev->open = omap4_keypad_open;
 421         input_dev->close = omap4_keypad_close;
 422
 423         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 424         if (!keypad_data->no_autorepeat)
 425                 __set_bit(EV_REP, input_dev->evbit);
 426
 427         input_set_drvdata(input_dev, keypad_data);
 428
 429         keypad_data->row_shift = get_count_order(keypad_data->cols);
 430         max_keys = keypad_data->rows << keypad_data->row_shift;
 431         keypad_data->keymap = devm_kcalloc(dev,
 432                                            max_keys,
 433                                            sizeof(keypad_data->keymap[0]),
 434                                            GFP_KERNEL);
 435         if (!keypad_data->keymap) {
 436                 dev_err(dev, "Not enough memory for keymap\n");
 437                 return -ENOMEM;
 438         }
 439
 440         error = matrix_keypad_build_keymap(NULL, NULL,
 441                                            keypad_data->rows, keypad_data->cols,
 442                                            keypad_data->keymap, input_dev);
 443         if (error) {
 444                 dev_err(dev, "failed to build keymap\n");
 445                 return error;
 446         }
 447
 448         error = devm_request_threaded_irq(dev, keypad_data->irq,
 449                                           omap4_keypad_irq_handler,
 450                                           omap4_keypad_irq_thread_fn,
 451                                           IRQF_ONESHOT,
 452                                           "omap4-keypad", keypad_data);
 453         if (error) {
 454                 dev_err(dev, "failed to register interrupt\n");
 455                 return error;
 456         }
 457
 458         error = input_register_device(keypad_data->input);
 459         if (error) {
 460                 dev_err(dev, "failed to register input device\n");
 461                 return error;
 462         }
 463
 464         device_init_wakeup(dev, true);
 465         error = dev_pm_set_wake_irq(dev, keypad_data->irq);
 466         if (error)
 467                 dev_warn(dev, "failed to set up wakeup irq: %d\n", error);
 468
 469         return 0;
 470 }
 471
 472 static int omap4_keypad_remove(struct platform_device *pdev)
 473 {
 474         dev_pm_clear_wake_irq(&pdev->dev);
 475
 476         return 0;
 477 }
 478
 479 static const struct of_device_id omap_keypad_dt_match[] = {
 480         { .compatible = "ti,omap4-keypad" },
 481         {},
 482 };
 483 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
 484
 485 static struct platform_driver omap4_keypad_driver = {
 486         .probe          = omap4_keypad_probe,
 487         .remove         = omap4_keypad_remove,
 488         .driver         = {
 489                 .name   = "omap4-keypad",
 490                 .of_match_table = omap_keypad_dt_match,
 491                 .pm = &omap4_keypad_pm_ops,
 492         },
 493 };
 494 module_platform_driver(omap4_keypad_driver);
 495
 496 MODULE_AUTHOR("Texas Instruments");
 497 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
 498 MODULE_LICENSE("GPL");
 499 MODULE_ALIAS("platform:omap4-keypad");