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