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_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         keypad_data->no_autorepeat = of_property_read_bool(np, "linux,input-no-autorepeat");
 278
 279         return 0;
 280 }
 281
 282 static int omap4_keypad_check_revision(struct device *dev,
 283                                        struct omap4_keypad *keypad_data)
 284 {
 285         unsigned int rev;
 286
 287         rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
 288         rev &= 0x03 << 30;
 289         rev >>= 30;
 290         switch (rev) {
 291         case KBD_REVISION_OMAP4:
 292                 keypad_data->reg_offset = 0x00;
 293                 keypad_data->irqreg_offset = 0x00;
 294                 break;
 295         case KBD_REVISION_OMAP5:
 296                 keypad_data->reg_offset = 0x10;
 297                 keypad_data->irqreg_offset = 0x0c;
 298                 break;
 299         default:
 300                 dev_err(dev, "Keypad reports unsupported revision %d", rev);
 301                 return -EINVAL;
 302         }
 303
 304         return 0;
 305 }
 306
 307 /*
 308  * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed".
 309  * Interrupt may not happen for key-up events. We must clear stuck
 310  * key-up events after the keyboard hardware has auto-idled.
 311  */
 312 static int omap4_keypad_runtime_suspend(struct device *dev)
 313 {
 314         struct platform_device *pdev = to_platform_device(dev);
 315         struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
 316         u32 active;
 317
 318         active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE);
 319         if (active) {
 320                 pm_runtime_mark_last_busy(dev);
 321                 return -EBUSY;
 322         }
 323
 324         omap4_keypad_scan_keys(keypad_data, 0);
 325
 326         return 0;
 327 }
 328
 329 static const struct dev_pm_ops omap4_keypad_pm_ops = {
 330         RUNTIME_PM_OPS(omap4_keypad_runtime_suspend, NULL, NULL)
 331 };
 332
 333 static void omap4_disable_pm(void *d)
 334 {
 335         pm_runtime_dont_use_autosuspend(d);
 336         pm_runtime_disable(d);
 337 }
 338
 339 static int omap4_keypad_probe(struct platform_device *pdev)
 340 {
 341         struct device *dev = &pdev->dev;
 342         struct omap4_keypad *keypad_data;
 343         struct input_dev *input_dev;
 344         unsigned int max_keys;
 345         int irq;
 346         int error;
 347
 348         irq = platform_get_irq(pdev, 0);
 349         if (irq < 0)
 350                 return irq;
 351
 352         keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
 353         if (!keypad_data) {
 354                 dev_err(dev, "keypad_data memory allocation failed\n");
 355                 return -ENOMEM;
 356         }
 357
 358         keypad_data->irq = irq;
 359         mutex_init(&keypad_data->lock);
 360         platform_set_drvdata(pdev, keypad_data);
 361
 362         error = omap4_keypad_parse_dt(dev, keypad_data);
 363         if (error)
 364                 return error;
 365
 366         keypad_data->base = devm_platform_ioremap_resource(pdev, 0);
 367         if (IS_ERR(keypad_data->base))
 368                 return PTR_ERR(keypad_data->base);
 369
 370         pm_runtime_use_autosuspend(dev);
 371         pm_runtime_set_autosuspend_delay(dev, OMAP4_KEYPAD_IDLE_CHECK_MS);
 372         pm_runtime_enable(dev);
 373
 374         error = devm_add_action_or_reset(dev, omap4_disable_pm, dev);
 375         if (error) {
 376                 dev_err(dev, "unable to register cleanup action\n");
 377                 return error;
 378         }
 379
 380         /*
 381          * Enable clocks for the keypad module so that we can read
 382          * revision register.
 383          */
 384         error = pm_runtime_resume_and_get(dev);
 385         if (error) {
 386                 dev_err(dev, "pm_runtime_resume_and_get() failed\n");
 387                 return error;
 388         }
 389
 390         error = omap4_keypad_check_revision(dev, keypad_data);
 391         if (!error) {
 392                 /* Ensure device does not raise interrupts */
 393                 omap4_keypad_stop(keypad_data);
 394         }
 395
 396         pm_runtime_mark_last_busy(dev);
 397         pm_runtime_put_autosuspend(dev);
 398         if (error)
 399                 return error;
 400
 401         /* input device allocation */
 402         keypad_data->input = input_dev = devm_input_allocate_device(dev);
 403         if (!input_dev)
 404                 return -ENOMEM;
 405
 406         input_dev->name = pdev->name;
 407         input_dev->id.bustype = BUS_HOST;
 408         input_dev->id.vendor = 0x0001;
 409         input_dev->id.product = 0x0001;
 410         input_dev->id.version = 0x0001;
 411
 412         input_dev->open = omap4_keypad_open;
 413         input_dev->close = omap4_keypad_close;
 414
 415         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 416         if (!keypad_data->no_autorepeat)
 417                 __set_bit(EV_REP, input_dev->evbit);
 418
 419         input_set_drvdata(input_dev, keypad_data);
 420
 421         keypad_data->row_shift = get_count_order(keypad_data->cols);
 422         max_keys = keypad_data->rows << keypad_data->row_shift;
 423         keypad_data->keymap = devm_kcalloc(dev,
 424                                            max_keys,
 425                                            sizeof(keypad_data->keymap[0]),
 426                                            GFP_KERNEL);
 427         if (!keypad_data->keymap) {
 428                 dev_err(dev, "Not enough memory for keymap\n");
 429                 return -ENOMEM;
 430         }
 431
 432         error = matrix_keypad_build_keymap(NULL, NULL,
 433                                            keypad_data->rows, keypad_data->cols,
 434                                            keypad_data->keymap, input_dev);
 435         if (error) {
 436                 dev_err(dev, "failed to build keymap\n");
 437                 return error;
 438         }
 439
 440         error = devm_request_threaded_irq(dev, keypad_data->irq,
 441                                           omap4_keypad_irq_handler,
 442                                           omap4_keypad_irq_thread_fn,
 443                                           IRQF_ONESHOT,
 444                                           "omap4-keypad", keypad_data);
 445         if (error) {
 446                 dev_err(dev, "failed to register interrupt\n");
 447                 return error;
 448         }
 449
 450         error = input_register_device(keypad_data->input);
 451         if (error) {
 452                 dev_err(dev, "failed to register input device\n");
 453                 return error;
 454         }
 455
 456         device_init_wakeup(dev, true);
 457         error = dev_pm_set_wake_irq(dev, keypad_data->irq);
 458         if (error)
 459                 dev_warn(dev, "failed to set up wakeup irq: %d\n", error);
 460
 461         return 0;
 462 }
 463
 464 static void omap4_keypad_remove(struct platform_device *pdev)
 465 {
 466         dev_pm_clear_wake_irq(&pdev->dev);
 467 }
 468
 469 static const struct of_device_id omap_keypad_dt_match[] = {
 470         { .compatible = "ti,omap4-keypad" },
 471         {},
 472 };
 473 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
 474
 475 static struct platform_driver omap4_keypad_driver = {
 476         .probe          = omap4_keypad_probe,
 477         .remove_new     = omap4_keypad_remove,
 478         .driver         = {
 479                 .name   = "omap4-keypad",
 480                 .of_match_table = omap_keypad_dt_match,
 481                 .pm = pm_ptr(&omap4_keypad_pm_ops),
 482         },
 483 };
 484 module_platform_driver(omap4_keypad_driver);
 485
 486 MODULE_AUTHOR("Texas Instruments");
 487 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
 488 MODULE_LICENSE("GPL");
 489 MODULE_ALIAS("platform:omap4-keypad");