drivers/input/keyboard/tegra-kbc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Keyboard class input driver for the NVIDIA Tegra SoC internal matrix
   4  * keyboard controller
   5  *
   6  * Copyright (c) 2009-2011, NVIDIA Corporation.
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/input.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/delay.h>
  14 #include <linux/io.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/of.h>
  17 #include <linux/of_device.h>
  18 #include <linux/clk.h>
  19 #include <linux/slab.h>
  20 #include <linux/input/matrix_keypad.h>
  21 #include <linux/reset.h>
  22 #include <linux/err.h>
  23
  24 #define KBC_MAX_KPENT   8
  25
  26 /* Maximum row/column supported by Tegra KBC yet  is 16x8 */
  27 #define KBC_MAX_GPIO    24
  28 /* Maximum keys supported by Tegra KBC yet is 16 x 8*/
  29 #define KBC_MAX_KEY     (16 * 8)
  30
  31 #define KBC_MAX_DEBOUNCE_CNT    0x3ffu
  32
  33 /* KBC row scan time and delay for beginning the row scan. */
  34 #define KBC_ROW_SCAN_TIME       16
  35 #define KBC_ROW_SCAN_DLY        5
  36
  37 /* KBC uses a 32KHz clock so a cycle = 1/32Khz */
  38 #define KBC_CYCLE_MS    32
  39
  40 /* KBC Registers */
  41
  42 /* KBC Control Register */
  43 #define KBC_CONTROL_0   0x0
  44 #define KBC_FIFO_TH_CNT_SHIFT(cnt)      (cnt << 14)
  45 #define KBC_DEBOUNCE_CNT_SHIFT(cnt)     (cnt << 4)
  46 #define KBC_CONTROL_FIFO_CNT_INT_EN     (1 << 3)
  47 #define KBC_CONTROL_KEYPRESS_INT_EN     (1 << 1)
  48 #define KBC_CONTROL_KBC_EN              (1 << 0)
  49
  50 /* KBC Interrupt Register */
  51 #define KBC_INT_0       0x4
  52 #define KBC_INT_FIFO_CNT_INT_STATUS     (1 << 2)
  53 #define KBC_INT_KEYPRESS_INT_STATUS     (1 << 0)
  54
  55 #define KBC_ROW_CFG0_0  0x8
  56 #define KBC_COL_CFG0_0  0x18
  57 #define KBC_TO_CNT_0    0x24
  58 #define KBC_INIT_DLY_0  0x28
  59 #define KBC_RPT_DLY_0   0x2c
  60 #define KBC_KP_ENT0_0   0x30
  61 #define KBC_KP_ENT1_0   0x34
  62 #define KBC_ROW0_MASK_0 0x38
  63
  64 #define KBC_ROW_SHIFT   3
  65
  66 enum tegra_pin_type {
  67         PIN_CFG_IGNORE,
  68         PIN_CFG_COL,
  69         PIN_CFG_ROW,
  70 };
  71
  72 /* Tegra KBC hw support */
  73 struct tegra_kbc_hw_support {
  74         int max_rows;
  75         int max_columns;
  76 };
  77
  78 struct tegra_kbc_pin_cfg {
  79         enum tegra_pin_type type;
  80         unsigned char num;
  81 };
  82
  83 struct tegra_kbc {
  84         struct device *dev;
  85         unsigned int debounce_cnt;
  86         unsigned int repeat_cnt;
  87         struct tegra_kbc_pin_cfg pin_cfg[KBC_MAX_GPIO];
  88         const struct matrix_keymap_data *keymap_data;
  89         bool wakeup;
  90         void __iomem *mmio;
  91         struct input_dev *idev;
  92         int irq;
  93         spinlock_t lock;
  94         unsigned int repoll_dly;
  95         unsigned long cp_dly_jiffies;
  96         unsigned int cp_to_wkup_dly;
  97         bool use_fn_map;
  98         bool use_ghost_filter;
  99         bool keypress_caused_wake;
 100         unsigned short keycode[KBC_MAX_KEY * 2];
 101         unsigned short current_keys[KBC_MAX_KPENT];
 102         unsigned int num_pressed_keys;
 103         u32 wakeup_key;
 104         struct timer_list timer;
 105         struct clk *clk;
 106         struct reset_control *rst;
 107         const struct tegra_kbc_hw_support *hw_support;
 108         int max_keys;
 109         int num_rows_and_columns;
 110 };
 111
 112 static void tegra_kbc_report_released_keys(struct input_dev *input,
 113                                            unsigned short old_keycodes[],
 114                                            unsigned int old_num_keys,
 115                                            unsigned short new_keycodes[],
 116                                            unsigned int new_num_keys)
 117 {
 118         unsigned int i, j;
 119
 120         for (i = 0; i < old_num_keys; i++) {
 121                 for (j = 0; j < new_num_keys; j++)
 122                         if (old_keycodes[i] == new_keycodes[j])
 123                                 break;
 124
 125                 if (j == new_num_keys)
 126                         input_report_key(input, old_keycodes[i], 0);
 127         }
 128 }
 129
 130 static void tegra_kbc_report_pressed_keys(struct input_dev *input,
 131                                           unsigned char scancodes[],
 132                                           unsigned short keycodes[],
 133                                           unsigned int num_pressed_keys)
 134 {
 135         unsigned int i;
 136
 137         for (i = 0; i < num_pressed_keys; i++) {
 138                 input_event(input, EV_MSC, MSC_SCAN, scancodes[i]);
 139                 input_report_key(input, keycodes[i], 1);
 140         }
 141 }
 142
 143 static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
 144 {
 145         unsigned char scancodes[KBC_MAX_KPENT];
 146         unsigned short keycodes[KBC_MAX_KPENT];
 147         u32 val = 0;
 148         unsigned int i;
 149         unsigned int num_down = 0;
 150         bool fn_keypress = false;
 151         bool key_in_same_row = false;
 152         bool key_in_same_col = false;
 153
 154         for (i = 0; i < KBC_MAX_KPENT; i++) {
 155                 if ((i % 4) == 0)
 156                         val = readl(kbc->mmio + KBC_KP_ENT0_0 + i);
 157
 158                 if (val & 0x80) {
 159                         unsigned int col = val & 0x07;
 160                         unsigned int row = (val >> 3) & 0x0f;
 161                         unsigned char scancode =
 162                                 MATRIX_SCAN_CODE(row, col, KBC_ROW_SHIFT);
 163
 164                         scancodes[num_down] = scancode;
 165                         keycodes[num_down] = kbc->keycode[scancode];
 166                         /* If driver uses Fn map, do not report the Fn key. */
 167                         if ((keycodes[num_down] == KEY_FN) && kbc->use_fn_map)
 168                                 fn_keypress = true;
 169                         else
 170                                 num_down++;
 171                 }
 172
 173                 val >>= 8;
 174         }
 175
 176         /*
 177          * Matrix keyboard designs are prone to keyboard ghosting.
 178          * Ghosting occurs if there are 3 keys such that -
 179          * any 2 of the 3 keys share a row, and any 2 of them share a column.
 180          * If so ignore the key presses for this iteration.
 181          */
 182         if (kbc->use_ghost_filter && num_down >= 3) {
 183                 for (i = 0; i < num_down; i++) {
 184                         unsigned int j;
 185                         u8 curr_col = scancodes[i] & 0x07;
 186                         u8 curr_row = scancodes[i] >> KBC_ROW_SHIFT;
 187
 188                         /*
 189                          * Find 2 keys such that one key is in the same row
 190                          * and the other is in the same column as the i-th key.
 191                          */
 192                         for (j = i + 1; j < num_down; j++) {
 193                                 u8 col = scancodes[j] & 0x07;
 194                                 u8 row = scancodes[j] >> KBC_ROW_SHIFT;
 195
 196                                 if (col == curr_col)
 197                                         key_in_same_col = true;
 198                                 if (row == curr_row)
 199                                         key_in_same_row = true;
 200                         }
 201                 }
 202         }
 203
 204         /*
 205          * If the platform uses Fn keymaps, translate keys on a Fn keypress.
 206          * Function keycodes are max_keys apart from the plain keycodes.
 207          */
 208         if (fn_keypress) {
 209                 for (i = 0; i < num_down; i++) {
 210                         scancodes[i] += kbc->max_keys;
 211                         keycodes[i] = kbc->keycode[scancodes[i]];
 212                 }
 213         }
 214
 215         /* Ignore the key presses for this iteration? */
 216         if (key_in_same_col && key_in_same_row)
 217                 return;
 218
 219         tegra_kbc_report_released_keys(kbc->idev,
 220                                        kbc->current_keys, kbc->num_pressed_keys,
 221                                        keycodes, num_down);
 222         tegra_kbc_report_pressed_keys(kbc->idev, scancodes, keycodes, num_down);
 223         input_sync(kbc->idev);
 224
 225         memcpy(kbc->current_keys, keycodes, sizeof(kbc->current_keys));
 226         kbc->num_pressed_keys = num_down;
 227 }
 228
 229 static void tegra_kbc_set_fifo_interrupt(struct tegra_kbc *kbc, bool enable)
 230 {
 231         u32 val;
 232
 233         val = readl(kbc->mmio + KBC_CONTROL_0);
 234         if (enable)
 235                 val |= KBC_CONTROL_FIFO_CNT_INT_EN;
 236         else
 237                 val &= ~KBC_CONTROL_FIFO_CNT_INT_EN;
 238         writel(val, kbc->mmio + KBC_CONTROL_0);
 239 }
 240
 241 static void tegra_kbc_keypress_timer(struct timer_list *t)
 242 {
 243         struct tegra_kbc *kbc = from_timer(kbc, t, timer);
 244         unsigned long flags;
 245         u32 val;
 246         unsigned int i;
 247
 248         spin_lock_irqsave(&kbc->lock, flags);
 249
 250         val = (readl(kbc->mmio + KBC_INT_0) >> 4) & 0xf;
 251         if (val) {
 252                 unsigned long dly;
 253
 254                 tegra_kbc_report_keys(kbc);
 255
 256                 /*
 257                  * If more than one keys are pressed we need not wait
 258                  * for the repoll delay.
 259                  */
 260                 dly = (val == 1) ? kbc->repoll_dly : 1;
 261                 mod_timer(&kbc->timer, jiffies + msecs_to_jiffies(dly));
 262         } else {
 263                 /* Release any pressed keys and exit the polling loop */
 264                 for (i = 0; i < kbc->num_pressed_keys; i++)
 265                         input_report_key(kbc->idev, kbc->current_keys[i], 0);
 266                 input_sync(kbc->idev);
 267
 268                 kbc->num_pressed_keys = 0;
 269
 270                 /* All keys are released so enable the keypress interrupt */
 271                 tegra_kbc_set_fifo_interrupt(kbc, true);
 272         }
 273
 274         spin_unlock_irqrestore(&kbc->lock, flags);
 275 }
 276
 277 static irqreturn_t tegra_kbc_isr(int irq, void *args)
 278 {
 279         struct tegra_kbc *kbc = args;
 280         unsigned long flags;
 281         u32 val;
 282
 283         spin_lock_irqsave(&kbc->lock, flags);
 284
 285         /*
 286          * Quickly bail out & reenable interrupts if the fifo threshold
 287          * count interrupt wasn't the interrupt source
 288          */
 289         val = readl(kbc->mmio + KBC_INT_0);
 290         writel(val, kbc->mmio + KBC_INT_0);
 291
 292         if (val & KBC_INT_FIFO_CNT_INT_STATUS) {
 293                 /*
 294                  * Until all keys are released, defer further processing to
 295                  * the polling loop in tegra_kbc_keypress_timer.
 296                  */
 297                 tegra_kbc_set_fifo_interrupt(kbc, false);
 298                 mod_timer(&kbc->timer, jiffies + kbc->cp_dly_jiffies);
 299         } else if (val & KBC_INT_KEYPRESS_INT_STATUS) {
 300                 /* We can be here only through system resume path */
 301                 kbc->keypress_caused_wake = true;
 302         }
 303
 304         spin_unlock_irqrestore(&kbc->lock, flags);
 305
 306         return IRQ_HANDLED;
 307 }
 308
 309 static void tegra_kbc_setup_wakekeys(struct tegra_kbc *kbc, bool filter)
 310 {
 311         int i;
 312         unsigned int rst_val;
 313
 314         /* Either mask all keys or none. */
 315         rst_val = (filter && !kbc->wakeup) ? ~0 : 0;
 316
 317         for (i = 0; i < kbc->hw_support->max_rows; i++)
 318                 writel(rst_val, kbc->mmio + KBC_ROW0_MASK_0 + i * 4);
 319 }
 320
 321 static void tegra_kbc_config_pins(struct tegra_kbc *kbc)
 322 {
 323         int i;
 324
 325         for (i = 0; i < KBC_MAX_GPIO; i++) {
 326                 u32 r_shft = 5 * (i % 6);
 327                 u32 c_shft = 4 * (i % 8);
 328                 u32 r_mask = 0x1f << r_shft;
 329                 u32 c_mask = 0x0f << c_shft;
 330                 u32 r_offs = (i / 6) * 4 + KBC_ROW_CFG0_0;
 331                 u32 c_offs = (i / 8) * 4 + KBC_COL_CFG0_0;
 332                 u32 row_cfg = readl(kbc->mmio + r_offs);
 333                 u32 col_cfg = readl(kbc->mmio + c_offs);
 334
 335                 row_cfg &= ~r_mask;
 336                 col_cfg &= ~c_mask;
 337
 338                 switch (kbc->pin_cfg[i].type) {
 339                 case PIN_CFG_ROW:
 340                         row_cfg |= ((kbc->pin_cfg[i].num << 1) | 1) << r_shft;
 341                         break;
 342
 343                 case PIN_CFG_COL:
 344                         col_cfg |= ((kbc->pin_cfg[i].num << 1) | 1) << c_shft;
 345                         break;
 346
 347                 case PIN_CFG_IGNORE:
 348                         break;
 349                 }
 350
 351                 writel(row_cfg, kbc->mmio + r_offs);
 352                 writel(col_cfg, kbc->mmio + c_offs);
 353         }
 354 }
 355
 356 static int tegra_kbc_start(struct tegra_kbc *kbc)
 357 {
 358         unsigned int debounce_cnt;
 359         u32 val = 0;
 360         int ret;
 361
 362         ret = clk_prepare_enable(kbc->clk);
 363         if (ret)
 364                 return ret;
 365
 366         /* Reset the KBC controller to clear all previous status.*/
 367         reset_control_assert(kbc->rst);
 368         udelay(100);
 369         reset_control_deassert(kbc->rst);
 370         udelay(100);
 371
 372         tegra_kbc_config_pins(kbc);
 373         tegra_kbc_setup_wakekeys(kbc, false);
 374
 375         writel(kbc->repeat_cnt, kbc->mmio + KBC_RPT_DLY_0);
 376
 377         /* Keyboard debounce count is maximum of 12 bits. */
 378         debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
 379         val = KBC_DEBOUNCE_CNT_SHIFT(debounce_cnt);
 380         val |= KBC_FIFO_TH_CNT_SHIFT(1); /* set fifo interrupt threshold to 1 */
 381         val |= KBC_CONTROL_FIFO_CNT_INT_EN;  /* interrupt on FIFO threshold */
 382         val |= KBC_CONTROL_KBC_EN;     /* enable */
 383         writel(val, kbc->mmio + KBC_CONTROL_0);
 384
 385         /*
 386          * Compute the delay(ns) from interrupt mode to continuous polling
 387          * mode so the timer routine is scheduled appropriately.
 388          */
 389         val = readl(kbc->mmio + KBC_INIT_DLY_0);
 390         kbc->cp_dly_jiffies = usecs_to_jiffies((val & 0xfffff) * 32);
 391
 392         kbc->num_pressed_keys = 0;
 393
 394         /*
 395          * Atomically clear out any remaining entries in the key FIFO
 396          * and enable keyboard interrupts.
 397          */
 398         while (1) {
 399                 val = readl(kbc->mmio + KBC_INT_0);
 400                 val >>= 4;
 401                 if (!val)
 402                         break;
 403
 404                 val = readl(kbc->mmio + KBC_KP_ENT0_0);
 405                 val = readl(kbc->mmio + KBC_KP_ENT1_0);
 406         }
 407         writel(0x7, kbc->mmio + KBC_INT_0);
 408
 409         enable_irq(kbc->irq);
 410
 411         return 0;
 412 }
 413
 414 static void tegra_kbc_stop(struct tegra_kbc *kbc)
 415 {
 416         unsigned long flags;
 417         u32 val;
 418
 419         spin_lock_irqsave(&kbc->lock, flags);
 420         val = readl(kbc->mmio + KBC_CONTROL_0);
 421         val &= ~1;
 422         writel(val, kbc->mmio + KBC_CONTROL_0);
 423         spin_unlock_irqrestore(&kbc->lock, flags);
 424
 425         disable_irq(kbc->irq);
 426         del_timer_sync(&kbc->timer);
 427
 428         clk_disable_unprepare(kbc->clk);
 429 }
 430
 431 static int tegra_kbc_open(struct input_dev *dev)
 432 {
 433         struct tegra_kbc *kbc = input_get_drvdata(dev);
 434
 435         return tegra_kbc_start(kbc);
 436 }
 437
 438 static void tegra_kbc_close(struct input_dev *dev)
 439 {
 440         struct tegra_kbc *kbc = input_get_drvdata(dev);
 441
 442         return tegra_kbc_stop(kbc);
 443 }
 444
 445 static bool tegra_kbc_check_pin_cfg(const struct tegra_kbc *kbc,
 446                                         unsigned int *num_rows)
 447 {
 448         int i;
 449
 450         *num_rows = 0;
 451
 452         for (i = 0; i < KBC_MAX_GPIO; i++) {
 453                 const struct tegra_kbc_pin_cfg *pin_cfg = &kbc->pin_cfg[i];
 454
 455                 switch (pin_cfg->type) {
 456                 case PIN_CFG_ROW:
 457                         if (pin_cfg->num >= kbc->hw_support->max_rows) {
 458                                 dev_err(kbc->dev,
 459                                         "pin_cfg[%d]: invalid row number %d\n",
 460                                         i, pin_cfg->num);
 461                                 return false;
 462                         }
 463                         (*num_rows)++;
 464                         break;
 465
 466                 case PIN_CFG_COL:
 467                         if (pin_cfg->num >= kbc->hw_support->max_columns) {
 468                                 dev_err(kbc->dev,
 469                                         "pin_cfg[%d]: invalid column number %d\n",
 470                                         i, pin_cfg->num);
 471                                 return false;
 472                         }
 473                         break;
 474
 475                 case PIN_CFG_IGNORE:
 476                         break;
 477
 478                 default:
 479                         dev_err(kbc->dev,
 480                                 "pin_cfg[%d]: invalid entry type %d\n",
 481                                 pin_cfg->type, pin_cfg->num);
 482                         return false;
 483                 }
 484         }
 485
 486         return true;
 487 }
 488
 489 static int tegra_kbc_parse_dt(struct tegra_kbc *kbc)
 490 {
 491         struct device_node *np = kbc->dev->of_node;
 492         u32 prop;
 493         int i;
 494         u32 num_rows = 0;
 495         u32 num_cols = 0;
 496         u32 cols_cfg[KBC_MAX_GPIO];
 497         u32 rows_cfg[KBC_MAX_GPIO];
 498         int proplen;
 499         int ret;
 500
 501         if (!of_property_read_u32(np, "nvidia,debounce-delay-ms", &prop))
 502                 kbc->debounce_cnt = prop;
 503
 504         if (!of_property_read_u32(np, "nvidia,repeat-delay-ms", &prop))
 505                 kbc->repeat_cnt = prop;
 506
 507         if (of_find_property(np, "nvidia,needs-ghost-filter", NULL))
 508                 kbc->use_ghost_filter = true;
 509
 510         if (of_property_read_bool(np, "wakeup-source") ||
 511             of_property_read_bool(np, "nvidia,wakeup-source")) /* legacy */
 512                 kbc->wakeup = true;
 513
 514         if (!of_get_property(np, "nvidia,kbc-row-pins", &proplen)) {
 515                 dev_err(kbc->dev, "property nvidia,kbc-row-pins not found\n");
 516                 return -ENOENT;
 517         }
 518         num_rows = proplen / sizeof(u32);
 519
 520         if (!of_get_property(np, "nvidia,kbc-col-pins", &proplen)) {
 521                 dev_err(kbc->dev, "property nvidia,kbc-col-pins not found\n");
 522                 return -ENOENT;
 523         }
 524         num_cols = proplen / sizeof(u32);
 525
 526         if (num_rows > kbc->hw_support->max_rows) {
 527                 dev_err(kbc->dev,
 528                         "Number of rows is more than supported by hardware\n");
 529                 return -EINVAL;
 530         }
 531
 532         if (num_cols > kbc->hw_support->max_columns) {
 533                 dev_err(kbc->dev,
 534                         "Number of cols is more than supported by hardware\n");
 535                 return -EINVAL;
 536         }
 537
 538         if (!of_get_property(np, "linux,keymap", &proplen)) {
 539                 dev_err(kbc->dev, "property linux,keymap not found\n");
 540                 return -ENOENT;
 541         }
 542
 543         if (!num_rows || !num_cols || ((num_rows + num_cols) > KBC_MAX_GPIO)) {
 544                 dev_err(kbc->dev,
 545                         "keypad rows/columns not properly specified\n");
 546                 return -EINVAL;
 547         }
 548
 549         /* Set all pins as non-configured */
 550         for (i = 0; i < kbc->num_rows_and_columns; i++)
 551                 kbc->pin_cfg[i].type = PIN_CFG_IGNORE;
 552
 553         ret = of_property_read_u32_array(np, "nvidia,kbc-row-pins",
 554                                 rows_cfg, num_rows);
 555         if (ret < 0) {
 556                 dev_err(kbc->dev, "Rows configurations are not proper\n");
 557                 return -EINVAL;
 558         }
 559
 560         ret = of_property_read_u32_array(np, "nvidia,kbc-col-pins",
 561                                 cols_cfg, num_cols);
 562         if (ret < 0) {
 563                 dev_err(kbc->dev, "Cols configurations are not proper\n");
 564                 return -EINVAL;
 565         }
 566
 567         for (i = 0; i < num_rows; i++) {
 568                 kbc->pin_cfg[rows_cfg[i]].type = PIN_CFG_ROW;
 569                 kbc->pin_cfg[rows_cfg[i]].num = i;
 570         }
 571
 572         for (i = 0; i < num_cols; i++) {
 573                 kbc->pin_cfg[cols_cfg[i]].type = PIN_CFG_COL;
 574                 kbc->pin_cfg[cols_cfg[i]].num = i;
 575         }
 576
 577         return 0;
 578 }
 579
 580 static const struct tegra_kbc_hw_support tegra20_kbc_hw_support = {
 581         .max_rows       = 16,
 582         .max_columns    = 8,
 583 };
 584
 585 static const struct tegra_kbc_hw_support tegra11_kbc_hw_support = {
 586         .max_rows       = 11,
 587         .max_columns    = 8,
 588 };
 589
 590 static const struct of_device_id tegra_kbc_of_match[] = {
 591         { .compatible = "nvidia,tegra114-kbc", .data = &tegra11_kbc_hw_support},
 592         { .compatible = "nvidia,tegra30-kbc", .data = &tegra20_kbc_hw_support},
 593         { .compatible = "nvidia,tegra20-kbc", .data = &tegra20_kbc_hw_support},
 594         { },
 595 };
 596 MODULE_DEVICE_TABLE(of, tegra_kbc_of_match);
 597
 598 static int tegra_kbc_probe(struct platform_device *pdev)
 599 {
 600         struct tegra_kbc *kbc;
 601         struct resource *res;
 602         int err;
 603         int num_rows = 0;
 604         unsigned int debounce_cnt;
 605         unsigned int scan_time_rows;
 606         unsigned int keymap_rows;
 607         const struct of_device_id *match;
 608
 609         match = of_match_device(tegra_kbc_of_match, &pdev->dev);
 610
 611         kbc = devm_kzalloc(&pdev->dev, sizeof(*kbc), GFP_KERNEL);
 612         if (!kbc) {
 613                 dev_err(&pdev->dev, "failed to alloc memory for kbc\n");
 614                 return -ENOMEM;
 615         }
 616
 617         kbc->dev = &pdev->dev;
 618         kbc->hw_support = match->data;
 619         kbc->max_keys = kbc->hw_support->max_rows *
 620                                 kbc->hw_support->max_columns;
 621         kbc->num_rows_and_columns = kbc->hw_support->max_rows +
 622                                         kbc->hw_support->max_columns;
 623         keymap_rows = kbc->max_keys;
 624         spin_lock_init(&kbc->lock);
 625
 626         err = tegra_kbc_parse_dt(kbc);
 627         if (err)
 628                 return err;
 629
 630         if (!tegra_kbc_check_pin_cfg(kbc, &num_rows))
 631                 return -EINVAL;
 632
 633         kbc->irq = platform_get_irq(pdev, 0);
 634         if (kbc->irq < 0)
 635                 return -ENXIO;
 636
 637         kbc->idev = devm_input_allocate_device(&pdev->dev);
 638         if (!kbc->idev) {
 639                 dev_err(&pdev->dev, "failed to allocate input device\n");
 640                 return -ENOMEM;
 641         }
 642
 643         timer_setup(&kbc->timer, tegra_kbc_keypress_timer, 0);
 644
 645         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 646         kbc->mmio = devm_ioremap_resource(&pdev->dev, res);
 647         if (IS_ERR(kbc->mmio))
 648                 return PTR_ERR(kbc->mmio);
 649
 650         kbc->clk = devm_clk_get(&pdev->dev, NULL);
 651         if (IS_ERR(kbc->clk)) {
 652                 dev_err(&pdev->dev, "failed to get keyboard clock\n");
 653                 return PTR_ERR(kbc->clk);
 654         }
 655
 656         kbc->rst = devm_reset_control_get(&pdev->dev, "kbc");
 657         if (IS_ERR(kbc->rst)) {
 658                 dev_err(&pdev->dev, "failed to get keyboard reset\n");
 659                 return PTR_ERR(kbc->rst);
 660         }
 661
 662         /*
 663          * The time delay between two consecutive reads of the FIFO is
 664          * the sum of the repeat time and the time taken for scanning
 665          * the rows. There is an additional delay before the row scanning
 666          * starts. The repoll delay is computed in milliseconds.
 667          */
 668         debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
 669         scan_time_rows = (KBC_ROW_SCAN_TIME + debounce_cnt) * num_rows;
 670         kbc->repoll_dly = KBC_ROW_SCAN_DLY + scan_time_rows + kbc->repeat_cnt;
 671         kbc->repoll_dly = DIV_ROUND_UP(kbc->repoll_dly, KBC_CYCLE_MS);
 672
 673         kbc->idev->name = pdev->name;
 674         kbc->idev->id.bustype = BUS_HOST;
 675         kbc->idev->dev.parent = &pdev->dev;
 676         kbc->idev->open = tegra_kbc_open;
 677         kbc->idev->close = tegra_kbc_close;
 678
 679         if (kbc->keymap_data && kbc->use_fn_map)
 680                 keymap_rows *= 2;
 681
 682         err = matrix_keypad_build_keymap(kbc->keymap_data, NULL,
 683                                          keymap_rows,
 684                                          kbc->hw_support->max_columns,
 685                                          kbc->keycode, kbc->idev);
 686         if (err) {
 687                 dev_err(&pdev->dev, "failed to setup keymap\n");
 688                 return err;
 689         }
 690
 691         __set_bit(EV_REP, kbc->idev->evbit);
 692         input_set_capability(kbc->idev, EV_MSC, MSC_SCAN);
 693
 694         input_set_drvdata(kbc->idev, kbc);
 695
 696         err = devm_request_irq(&pdev->dev, kbc->irq, tegra_kbc_isr,
 697                                IRQF_TRIGGER_HIGH, pdev->name, kbc);
 698         if (err) {
 699                 dev_err(&pdev->dev, "failed to request keyboard IRQ\n");
 700                 return err;
 701         }
 702
 703         disable_irq(kbc->irq);
 704
 705         err = input_register_device(kbc->idev);
 706         if (err) {
 707                 dev_err(&pdev->dev, "failed to register input device\n");
 708                 return err;
 709         }
 710
 711         platform_set_drvdata(pdev, kbc);
 712         device_init_wakeup(&pdev->dev, kbc->wakeup);
 713
 714         return 0;
 715 }
 716
 717 #ifdef CONFIG_PM_SLEEP
 718 static void tegra_kbc_set_keypress_interrupt(struct tegra_kbc *kbc, bool enable)
 719 {
 720         u32 val;
 721
 722         val = readl(kbc->mmio + KBC_CONTROL_0);
 723         if (enable)
 724                 val |= KBC_CONTROL_KEYPRESS_INT_EN;
 725         else
 726                 val &= ~KBC_CONTROL_KEYPRESS_INT_EN;
 727         writel(val, kbc->mmio + KBC_CONTROL_0);
 728 }
 729
 730 static int tegra_kbc_suspend(struct device *dev)
 731 {
 732         struct platform_device *pdev = to_platform_device(dev);
 733         struct tegra_kbc *kbc = platform_get_drvdata(pdev);
 734
 735         mutex_lock(&kbc->idev->mutex);
 736         if (device_may_wakeup(&pdev->dev)) {
 737                 disable_irq(kbc->irq);
 738                 del_timer_sync(&kbc->timer);
 739                 tegra_kbc_set_fifo_interrupt(kbc, false);
 740
 741                 /* Forcefully clear the interrupt status */
 742                 writel(0x7, kbc->mmio + KBC_INT_0);
 743                 /*
 744                  * Store the previous resident time of continuous polling mode.
 745                  * Force the keyboard into interrupt mode.
 746                  */
 747                 kbc->cp_to_wkup_dly = readl(kbc->mmio + KBC_TO_CNT_0);
 748                 writel(0, kbc->mmio + KBC_TO_CNT_0);
 749
 750                 tegra_kbc_setup_wakekeys(kbc, true);
 751                 msleep(30);
 752
 753                 kbc->keypress_caused_wake = false;
 754                 /* Enable keypress interrupt before going into suspend. */
 755                 tegra_kbc_set_keypress_interrupt(kbc, true);
 756                 enable_irq(kbc->irq);
 757                 enable_irq_wake(kbc->irq);
 758         } else {
 759                 if (input_device_enabled(kbc->idev))
 760                         tegra_kbc_stop(kbc);
 761         }
 762         mutex_unlock(&kbc->idev->mutex);
 763
 764         return 0;
 765 }
 766
 767 static int tegra_kbc_resume(struct device *dev)
 768 {
 769         struct platform_device *pdev = to_platform_device(dev);
 770         struct tegra_kbc *kbc = platform_get_drvdata(pdev);
 771         int err = 0;
 772
 773         mutex_lock(&kbc->idev->mutex);
 774         if (device_may_wakeup(&pdev->dev)) {
 775                 disable_irq_wake(kbc->irq);
 776                 tegra_kbc_setup_wakekeys(kbc, false);
 777                 /* We will use fifo interrupts for key detection. */
 778                 tegra_kbc_set_keypress_interrupt(kbc, false);
 779
 780                 /* Restore the resident time of continuous polling mode. */
 781                 writel(kbc->cp_to_wkup_dly, kbc->mmio + KBC_TO_CNT_0);
 782
 783                 tegra_kbc_set_fifo_interrupt(kbc, true);
 784
 785                 if (kbc->keypress_caused_wake && kbc->wakeup_key) {
 786                         /*
 787                          * We can't report events directly from the ISR
 788                          * because timekeeping is stopped when processing
 789                          * wakeup request and we get a nasty warning when
 790                          * we try to call do_gettimeofday() in evdev
 791                          * handler.
 792                          */
 793                         input_report_key(kbc->idev, kbc->wakeup_key, 1);
 794                         input_sync(kbc->idev);
 795                         input_report_key(kbc->idev, kbc->wakeup_key, 0);
 796                         input_sync(kbc->idev);
 797                 }
 798         } else {
 799                 if (input_device_enabled(kbc->idev))
 800                         err = tegra_kbc_start(kbc);
 801         }
 802         mutex_unlock(&kbc->idev->mutex);
 803
 804         return err;
 805 }
 806 #endif
 807
 808 static SIMPLE_DEV_PM_OPS(tegra_kbc_pm_ops, tegra_kbc_suspend, tegra_kbc_resume);
 809
 810 static struct platform_driver tegra_kbc_driver = {
 811         .probe          = tegra_kbc_probe,
 812         .driver = {
 813                 .name   = "tegra-kbc",
 814                 .pm     = &tegra_kbc_pm_ops,
 815                 .of_match_table = tegra_kbc_of_match,
 816         },
 817 };
 818 module_platform_driver(tegra_kbc_driver);
 819
 820 MODULE_LICENSE("GPL");
 821 MODULE_AUTHOR("Rakesh Iyer <riyer@nvidia.com>");
 822 MODULE_DESCRIPTION("Tegra matrix keyboard controller driver");
 823 MODULE_ALIAS("platform:tegra-kbc");