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 <x0066660@ti.com>
   8  * Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
   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_get_sync(dev);
 183         if (error < 0) {
 184                 pm_runtime_put_noidle(dev);
 185                 return IRQ_NONE;
 186         }
 187
 188         low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
 189         high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
 190         keys = low | (u64)high << 32;
 191
 192         omap4_keypad_scan_keys(keypad_data, keys);
 193
 194         /* clear pending interrupts */
 195         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 196                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 197
 198         pm_runtime_mark_last_busy(dev);
 199         pm_runtime_put_autosuspend(dev);
 200
 201         return IRQ_HANDLED;
 202 }
 203
 204 static int omap4_keypad_open(struct input_dev *input)
 205 {
 206         struct omap4_keypad *keypad_data = input_get_drvdata(input);
 207         struct device *dev = input->dev.parent;
 208         int error;
 209
 210         error = pm_runtime_get_sync(dev);
 211         if (error < 0) {
 212                 pm_runtime_put_noidle(dev);
 213                 return error;
 214         }
 215
 216         disable_irq(keypad_data->irq);
 217
 218         kbd_writel(keypad_data, OMAP4_KBD_CTRL,
 219                         OMAP4_DEF_CTRL_NOSOFTMODE |
 220                         (OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
 221         kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
 222                         OMAP4_VAL_DEBOUNCINGTIME_16MS);
 223         /* clear pending interrupts */
 224         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 225                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 226         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 227                         OMAP4_DEF_IRQENABLE_EVENTEN);
 228         kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
 229                         OMAP4_DEF_WUP_EVENT_ENA);
 230
 231         enable_irq(keypad_data->irq);
 232
 233         pm_runtime_mark_last_busy(dev);
 234         pm_runtime_put_autosuspend(dev);
 235
 236         return 0;
 237 }
 238
 239 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
 240 {
 241         /* Disable interrupts and wake-up events */
 242         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 243                          OMAP4_VAL_IRQDISABLE);
 244         kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
 245
 246         /* clear pending interrupts */
 247         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 248                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 249 }
 250
 251 static void omap4_keypad_close(struct input_dev *input)
 252 {
 253         struct omap4_keypad *keypad_data = input_get_drvdata(input);
 254         struct device *dev = input->dev.parent;
 255         int error;
 256
 257         error = pm_runtime_get_sync(dev);
 258         if (error < 0)
 259                 pm_runtime_put_noidle(dev);
 260
 261         disable_irq(keypad_data->irq);
 262         omap4_keypad_stop(keypad_data);
 263         enable_irq(keypad_data->irq);
 264
 265         pm_runtime_mark_last_busy(dev);
 266         pm_runtime_put_autosuspend(dev);
 267 }
 268
 269 static int omap4_keypad_parse_dt(struct device *dev,
 270                                  struct omap4_keypad *keypad_data)
 271 {
 272         struct device_node *np = dev->of_node;
 273         int err;
 274
 275         err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
 276                                              &keypad_data->cols);
 277         if (err)
 278                 return err;
 279
 280         if (of_get_property(np, "linux,input-no-autorepeat", NULL))
 281                 keypad_data->no_autorepeat = true;
 282
 283         return 0;
 284 }
 285
 286 static int omap4_keypad_check_revision(struct device *dev,
 287                                        struct omap4_keypad *keypad_data)
 288 {
 289         unsigned int rev;
 290
 291         rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
 292         rev &= 0x03 << 30;
 293         rev >>= 30;
 294         switch (rev) {
 295         case KBD_REVISION_OMAP4:
 296                 keypad_data->reg_offset = 0x00;
 297                 keypad_data->irqreg_offset = 0x00;
 298                 break;
 299         case KBD_REVISION_OMAP5:
 300                 keypad_data->reg_offset = 0x10;
 301                 keypad_data->irqreg_offset = 0x0c;
 302                 break;
 303         default:
 304                 dev_err(dev, "Keypad reports unsupported revision %d", rev);
 305                 return -EINVAL;
 306         }
 307
 308         return 0;
 309 }
 310
 311 /*
 312  * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed".
 313  * Interrupt may not happen for key-up events. We must clear stuck
 314  * key-up events after the keyboard hardware has auto-idled.
 315  */
 316 static int __maybe_unused omap4_keypad_runtime_suspend(struct device *dev)
 317 {
 318         struct platform_device *pdev = to_platform_device(dev);
 319         struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
 320         u32 active;
 321
 322         active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE);
 323         if (active) {
 324                 pm_runtime_mark_last_busy(dev);
 325                 return -EBUSY;
 326         }
 327
 328         omap4_keypad_scan_keys(keypad_data, 0);
 329
 330         return 0;
 331 }
 332
 333 static const struct dev_pm_ops omap4_keypad_pm_ops = {
 334         SET_RUNTIME_PM_OPS(omap4_keypad_runtime_suspend, NULL, NULL)
 335 };
 336
 337 static void omap4_disable_pm(void *d)
 338 {
 339         pm_runtime_dont_use_autosuspend(d);
 340         pm_runtime_disable(d);
 341 }
 342
 343 static int omap4_keypad_probe(struct platform_device *pdev)
 344 {
 345         struct device *dev = &pdev->dev;
 346         struct omap4_keypad *keypad_data;
 347         struct input_dev *input_dev;
 348         struct resource *res;
 349         unsigned int max_keys;
 350         int irq;
 351         int error;
 352
 353         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 354         if (!res) {
 355                 dev_err(&pdev->dev, "no base address specified\n");
 356                 return -EINVAL;
 357         }
 358
 359         irq = platform_get_irq(pdev, 0);
 360         if (irq < 0)
 361                 return irq;
 362
 363         keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
 364         if (!keypad_data) {
 365                 dev_err(dev, "keypad_data memory allocation failed\n");
 366                 return -ENOMEM;
 367         }
 368
 369         keypad_data->irq = irq;
 370         mutex_init(&keypad_data->lock);
 371         platform_set_drvdata(pdev, keypad_data);
 372
 373         error = omap4_keypad_parse_dt(dev, keypad_data);
 374         if (error)
 375                 return error;
 376
 377         keypad_data->base = devm_ioremap_resource(dev, res);
 378         if (IS_ERR(keypad_data->base))
 379                 return PTR_ERR(keypad_data->base);
 380
 381         pm_runtime_use_autosuspend(dev);
 382         pm_runtime_set_autosuspend_delay(dev, OMAP4_KEYPAD_IDLE_CHECK_MS);
 383         pm_runtime_enable(dev);
 384
 385         error = devm_add_action_or_reset(dev, omap4_disable_pm, dev);
 386         if (error) {
 387                 dev_err(dev, "unable to register cleanup action\n");
 388                 return error;
 389         }
 390
 391         /*
 392          * Enable clocks for the keypad module so that we can read
 393          * revision register.
 394          */
 395         error = pm_runtime_get_sync(dev);
 396         if (error) {
 397                 dev_err(dev, "pm_runtime_get_sync() failed\n");
 398                 pm_runtime_put_noidle(dev);
 399                 return error;
 400         }
 401
 402         error = omap4_keypad_check_revision(dev, keypad_data);
 403         if (!error) {
 404                 /* Ensure device does not raise interrupts */
 405                 omap4_keypad_stop(keypad_data);
 406         }
 407
 408         pm_runtime_mark_last_busy(dev);
 409         pm_runtime_put_autosuspend(dev);
 410         if (error)
 411                 return error;
 412
 413         /* input device allocation */
 414         keypad_data->input = input_dev = devm_input_allocate_device(dev);
 415         if (!input_dev)
 416                 return -ENOMEM;
 417
 418         input_dev->name = pdev->name;
 419         input_dev->id.bustype = BUS_HOST;
 420         input_dev->id.vendor = 0x0001;
 421         input_dev->id.product = 0x0001;
 422         input_dev->id.version = 0x0001;
 423
 424         input_dev->open = omap4_keypad_open;
 425         input_dev->close = omap4_keypad_close;
 426
 427         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 428         if (!keypad_data->no_autorepeat)
 429                 __set_bit(EV_REP, input_dev->evbit);
 430
 431         input_set_drvdata(input_dev, keypad_data);
 432
 433         keypad_data->row_shift = get_count_order(keypad_data->cols);
 434         max_keys = keypad_data->rows << keypad_data->row_shift;
 435         keypad_data->keymap = devm_kcalloc(dev,
 436                                            max_keys,
 437                                            sizeof(keypad_data->keymap[0]),
 438                                            GFP_KERNEL);
 439         if (!keypad_data->keymap) {
 440                 dev_err(dev, "Not enough memory for keymap\n");
 441                 return -ENOMEM;
 442         }
 443
 444         error = matrix_keypad_build_keymap(NULL, NULL,
 445                                            keypad_data->rows, keypad_data->cols,
 446                                            keypad_data->keymap, input_dev);
 447         if (error) {
 448                 dev_err(dev, "failed to build keymap\n");
 449                 return error;
 450         }
 451
 452         error = devm_request_threaded_irq(dev, keypad_data->irq,
 453                                           omap4_keypad_irq_handler,
 454                                           omap4_keypad_irq_thread_fn,
 455                                           IRQF_ONESHOT,
 456                                           "omap4-keypad", keypad_data);
 457         if (error) {
 458                 dev_err(dev, "failed to register interrupt\n");
 459                 return error;
 460         }
 461
 462         error = input_register_device(keypad_data->input);
 463         if (error) {
 464                 dev_err(dev, "failed to register input device\n");
 465                 return error;
 466         }
 467
 468         device_init_wakeup(dev, true);
 469         error = dev_pm_set_wake_irq(dev, keypad_data->irq);
 470         if (error)
 471                 dev_warn(dev, "failed to set up wakeup irq: %d\n", error);
 472
 473         return 0;
 474 }
 475
 476 static int omap4_keypad_remove(struct platform_device *pdev)
 477 {
 478         dev_pm_clear_wake_irq(&pdev->dev);
 479
 480         return 0;
 481 }
 482
 483 static const struct of_device_id omap_keypad_dt_match[] = {
 484         { .compatible = "ti,omap4-keypad" },
 485         {},
 486 };
 487 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
 488
 489 static struct platform_driver omap4_keypad_driver = {
 490         .probe          = omap4_keypad_probe,
 491         .remove         = omap4_keypad_remove,
 492         .driver         = {
 493                 .name   = "omap4-keypad",
 494                 .of_match_table = omap_keypad_dt_match,
 495                 .pm = &omap4_keypad_pm_ops,
 496         },
 497 };
 498 module_platform_driver(omap4_keypad_driver);
 499
 500 MODULE_AUTHOR("Texas Instruments");
 501 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
 502 MODULE_LICENSE("GPL");
 503 MODULE_ALIAS("platform:omap4-keypad");