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
  64 enum {
  65         KBD_REVISION_OMAP4 = 0,
  66         KBD_REVISION_OMAP5,
  67 };
  68
  69 struct omap4_keypad {
  70         struct input_dev *input;
  71
  72         void __iomem *base;
  73         unsigned int irq;
  74
  75         unsigned int rows;
  76         unsigned int cols;
  77         u32 reg_offset;
  78         u32 irqreg_offset;
  79         unsigned int row_shift;
  80         bool no_autorepeat;
  81         unsigned char key_state[8];
  82         unsigned short *keymap;
  83 };
  84
  85 static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
  86 {
  87         return __raw_readl(keypad_data->base +
  88                                 keypad_data->reg_offset + offset);
  89 }
  90
  91 static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
  92 {
  93         __raw_writel(value,
  94                      keypad_data->base + keypad_data->reg_offset + offset);
  95 }
  96
  97 static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
  98 {
  99         return __raw_readl(keypad_data->base +
 100                                 keypad_data->irqreg_offset + offset);
 101 }
 102
 103 static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
 104                              u32 offset, u32 value)
 105 {
 106         __raw_writel(value,
 107                      keypad_data->base + keypad_data->irqreg_offset + offset);
 108 }
 109
 110
 111 /* Interrupt handlers */
 112 static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
 113 {
 114         struct omap4_keypad *keypad_data = dev_id;
 115
 116         if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
 117                 return IRQ_WAKE_THREAD;
 118
 119         return IRQ_NONE;
 120 }
 121
 122 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
 123 {
 124         struct omap4_keypad *keypad_data = dev_id;
 125         struct input_dev *input_dev = keypad_data->input;
 126         unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
 127         unsigned int col, row, code, changed;
 128         u32 *new_state = (u32 *) key_state;
 129
 130         *new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
 131         *(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
 132
 133         for (row = 0; row < keypad_data->rows; row++) {
 134                 changed = key_state[row] ^ keypad_data->key_state[row];
 135                 if (!changed)
 136                         continue;
 137
 138                 for (col = 0; col < keypad_data->cols; col++) {
 139                         if (changed & (1 << col)) {
 140                                 code = MATRIX_SCAN_CODE(row, col,
 141                                                 keypad_data->row_shift);
 142                                 input_event(input_dev, EV_MSC, MSC_SCAN, code);
 143                                 input_report_key(input_dev,
 144                                                  keypad_data->keymap[code],
 145                                                  key_state[row] & (1 << col));
 146                         }
 147                 }
 148         }
 149
 150         input_sync(input_dev);
 151
 152         memcpy(keypad_data->key_state, key_state,
 153                 sizeof(keypad_data->key_state));
 154
 155         /* clear pending interrupts */
 156         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 157                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 158
 159         return IRQ_HANDLED;
 160 }
 161
 162 static int omap4_keypad_open(struct input_dev *input)
 163 {
 164         struct omap4_keypad *keypad_data = input_get_drvdata(input);
 165
 166         pm_runtime_get_sync(input->dev.parent);
 167
 168         disable_irq(keypad_data->irq);
 169
 170         kbd_writel(keypad_data, OMAP4_KBD_CTRL,
 171                         OMAP4_DEF_CTRL_NOSOFTMODE |
 172                         (OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
 173         kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
 174                         OMAP4_VAL_DEBOUNCINGTIME_16MS);
 175         /* clear pending interrupts */
 176         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 177                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 178         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 179                         OMAP4_DEF_IRQENABLE_EVENTEN |
 180                                 OMAP4_DEF_IRQENABLE_LONGKEY);
 181         kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
 182                         OMAP4_DEF_WUP_EVENT_ENA | OMAP4_DEF_WUP_LONG_KEY_ENA);
 183
 184         enable_irq(keypad_data->irq);
 185
 186         return 0;
 187 }
 188
 189 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
 190 {
 191         /* Disable interrupts and wake-up events */
 192         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 193                          OMAP4_VAL_IRQDISABLE);
 194         kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
 195
 196         /* clear pending interrupts */
 197         kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 198                          kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 199 }
 200
 201 static void omap4_keypad_close(struct input_dev *input)
 202 {
 203         struct omap4_keypad *keypad_data;
 204
 205         keypad_data = input_get_drvdata(input);
 206         disable_irq(keypad_data->irq);
 207         omap4_keypad_stop(keypad_data);
 208         enable_irq(keypad_data->irq);
 209
 210         pm_runtime_put_sync(input->dev.parent);
 211 }
 212
 213 static int omap4_keypad_parse_dt(struct device *dev,
 214                                  struct omap4_keypad *keypad_data)
 215 {
 216         struct device_node *np = dev->of_node;
 217         int err;
 218
 219         err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
 220                                              &keypad_data->cols);
 221         if (err)
 222                 return err;
 223
 224         if (of_get_property(np, "linux,input-no-autorepeat", NULL))
 225                 keypad_data->no_autorepeat = true;
 226
 227         return 0;
 228 }
 229
 230 static int omap4_keypad_check_revision(struct device *dev,
 231                                        struct omap4_keypad *keypad_data)
 232 {
 233         unsigned int rev;
 234
 235         rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
 236         rev &= 0x03 << 30;
 237         rev >>= 30;
 238         switch (rev) {
 239         case KBD_REVISION_OMAP4:
 240                 keypad_data->reg_offset = 0x00;
 241                 keypad_data->irqreg_offset = 0x00;
 242                 break;
 243         case KBD_REVISION_OMAP5:
 244                 keypad_data->reg_offset = 0x10;
 245                 keypad_data->irqreg_offset = 0x0c;
 246                 break;
 247         default:
 248                 dev_err(dev, "Keypad reports unsupported revision %d", rev);
 249                 return -EINVAL;
 250         }
 251
 252         return 0;
 253 }
 254
 255 static int omap4_keypad_probe(struct platform_device *pdev)
 256 {
 257         struct omap4_keypad *keypad_data;
 258         struct input_dev *input_dev;
 259         struct resource *res;
 260         unsigned int max_keys;
 261         int irq;
 262         int error;
 263
 264         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 265         if (!res) {
 266                 dev_err(&pdev->dev, "no base address specified\n");
 267                 return -EINVAL;
 268         }
 269
 270         irq = platform_get_irq(pdev, 0);
 271         if (irq < 0)
 272                 return irq;
 273
 274         keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
 275         if (!keypad_data) {
 276                 dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
 277                 return -ENOMEM;
 278         }
 279
 280         keypad_data->irq = irq;
 281
 282         error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
 283         if (error)
 284                 goto err_free_keypad;
 285
 286         res = request_mem_region(res->start, resource_size(res), pdev->name);
 287         if (!res) {
 288                 dev_err(&pdev->dev, "can't request mem region\n");
 289                 error = -EBUSY;
 290                 goto err_free_keypad;
 291         }
 292
 293         keypad_data->base = ioremap(res->start, resource_size(res));
 294         if (!keypad_data->base) {
 295                 dev_err(&pdev->dev, "can't ioremap mem resource\n");
 296                 error = -ENOMEM;
 297                 goto err_release_mem;
 298         }
 299
 300         pm_runtime_enable(&pdev->dev);
 301
 302         /*
 303          * Enable clocks for the keypad module so that we can read
 304          * revision register.
 305          */
 306         error = pm_runtime_get_sync(&pdev->dev);
 307         if (error) {
 308                 dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
 309                 pm_runtime_put_noidle(&pdev->dev);
 310         } else {
 311                 error = omap4_keypad_check_revision(&pdev->dev,
 312                                                     keypad_data);
 313                 if (!error) {
 314                         /* Ensure device does not raise interrupts */
 315                         omap4_keypad_stop(keypad_data);
 316                 }
 317                 pm_runtime_put_sync(&pdev->dev);
 318         }
 319         if (error)
 320                 goto err_pm_disable;
 321
 322         /* input device allocation */
 323         keypad_data->input = input_dev = input_allocate_device();
 324         if (!input_dev) {
 325                 error = -ENOMEM;
 326                 goto err_pm_disable;
 327         }
 328
 329         input_dev->name = pdev->name;
 330         input_dev->dev.parent = &pdev->dev;
 331         input_dev->id.bustype = BUS_HOST;
 332         input_dev->id.vendor = 0x0001;
 333         input_dev->id.product = 0x0001;
 334         input_dev->id.version = 0x0001;
 335
 336         input_dev->open = omap4_keypad_open;
 337         input_dev->close = omap4_keypad_close;
 338
 339         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 340         if (!keypad_data->no_autorepeat)
 341                 __set_bit(EV_REP, input_dev->evbit);
 342
 343         input_set_drvdata(input_dev, keypad_data);
 344
 345         keypad_data->row_shift = get_count_order(keypad_data->cols);
 346         max_keys = keypad_data->rows << keypad_data->row_shift;
 347         keypad_data->keymap = kcalloc(max_keys,
 348                                       sizeof(keypad_data->keymap[0]),
 349                                       GFP_KERNEL);
 350         if (!keypad_data->keymap) {
 351                 dev_err(&pdev->dev, "Not enough memory for keymap\n");
 352                 error = -ENOMEM;
 353                 goto err_free_input;
 354         }
 355
 356         error = matrix_keypad_build_keymap(NULL, NULL,
 357                                            keypad_data->rows, keypad_data->cols,
 358                                            keypad_data->keymap, input_dev);
 359         if (error) {
 360                 dev_err(&pdev->dev, "failed to build keymap\n");
 361                 goto err_free_keymap;
 362         }
 363
 364         error = request_threaded_irq(keypad_data->irq, omap4_keypad_irq_handler,
 365                                      omap4_keypad_irq_thread_fn, IRQF_ONESHOT,
 366                                      "omap4-keypad", keypad_data);
 367         if (error) {
 368                 dev_err(&pdev->dev, "failed to register interrupt\n");
 369                 goto err_free_keymap;
 370         }
 371
 372         error = input_register_device(keypad_data->input);
 373         if (error < 0) {
 374                 dev_err(&pdev->dev, "failed to register input device\n");
 375                 goto err_free_irq;
 376         }
 377
 378         device_init_wakeup(&pdev->dev, true);
 379         error = dev_pm_set_wake_irq(&pdev->dev, keypad_data->irq);
 380         if (error)
 381                 dev_warn(&pdev->dev,
 382                          "failed to set up wakeup irq: %d\n", error);
 383
 384         platform_set_drvdata(pdev, keypad_data);
 385
 386         return 0;
 387
 388 err_free_irq:
 389         free_irq(keypad_data->irq, keypad_data);
 390 err_free_keymap:
 391         kfree(keypad_data->keymap);
 392 err_free_input:
 393         input_free_device(input_dev);
 394 err_pm_disable:
 395         pm_runtime_disable(&pdev->dev);
 396         iounmap(keypad_data->base);
 397 err_release_mem:
 398         release_mem_region(res->start, resource_size(res));
 399 err_free_keypad:
 400         kfree(keypad_data);
 401         return error;
 402 }
 403
 404 static int omap4_keypad_remove(struct platform_device *pdev)
 405 {
 406         struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
 407         struct resource *res;
 408
 409         dev_pm_clear_wake_irq(&pdev->dev);
 410
 411         free_irq(keypad_data->irq, keypad_data);
 412
 413         pm_runtime_disable(&pdev->dev);
 414
 415         input_unregister_device(keypad_data->input);
 416
 417         iounmap(keypad_data->base);
 418
 419         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 420         release_mem_region(res->start, resource_size(res));
 421
 422         kfree(keypad_data->keymap);
 423         kfree(keypad_data);
 424
 425         return 0;
 426 }
 427
 428 static const struct of_device_id omap_keypad_dt_match[] = {
 429         { .compatible = "ti,omap4-keypad" },
 430         {},
 431 };
 432 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
 433
 434 static struct platform_driver omap4_keypad_driver = {
 435         .probe          = omap4_keypad_probe,
 436         .remove         = omap4_keypad_remove,
 437         .driver         = {
 438                 .name   = "omap4-keypad",
 439                 .of_match_table = omap_keypad_dt_match,
 440         },
 441 };
 442 module_platform_driver(omap4_keypad_driver);
 443
 444 MODULE_AUTHOR("Texas Instruments");
 445 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
 446 MODULE_LICENSE("GPL");
 447 MODULE_ALIAS("platform:omap4-keypad");