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
66enum tegra_pin_type {
67 PIN_CFG_IGNORE,
68 PIN_CFG_COL,
69 PIN_CFG_ROW,
70};
71
72/* Tegra KBC hw support */
73struct tegra_kbc_hw_support {
74 int max_rows;
75 int max_columns;
76};
77
78struct tegra_kbc_pin_cfg {
79 enum tegra_pin_type type;
80 unsigned char num;
81};
82
83struct 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
112static 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(dev: input, code: old_keycodes[i], value: 0);
127 }
128}
129
130static 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(dev: input, EV_MSC, MSC_SCAN, value: scancodes[i]);
139 input_report_key(dev: input, code: keycodes[i], value: 1);
140 }
141}
142
143static 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(addr: 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(input: kbc->idev,
220 old_keycodes: kbc->current_keys, old_num_keys: kbc->num_pressed_keys,
221 new_keycodes: keycodes, new_num_keys: num_down);
222 tegra_kbc_report_pressed_keys(input: kbc->idev, scancodes, keycodes, num_pressed_keys: num_down);
223 input_sync(dev: kbc->idev);
224
225 memcpy(kbc->current_keys, keycodes, sizeof(kbc->current_keys));
226 kbc->num_pressed_keys = num_down;
227}
228
229static void tegra_kbc_set_fifo_interrupt(struct tegra_kbc *kbc, bool enable)
230{
231 u32 val;
232
233 val = readl(addr: 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, addr: kbc->mmio + KBC_CONTROL_0);
239}
240
241static 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(addr: 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(timer: &kbc->timer, expires: jiffies + msecs_to_jiffies(m: 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(dev: kbc->idev, code: kbc->current_keys[i], value: 0);
266 input_sync(dev: 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, enable: true);
272 }
273
274 spin_unlock_irqrestore(lock: &kbc->lock, flags);
275}
276
277static 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(addr: kbc->mmio + KBC_INT_0);
290 writel(val, addr: 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, enable: false);
298 mod_timer(timer: &kbc->timer, expires: 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(lock: &kbc->lock, flags);
305
306 return IRQ_HANDLED;
307}
308
309static 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(val: rst_val, addr: kbc->mmio + KBC_ROW0_MASK_0 + i * 4);
319}
320
321static 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(addr: kbc->mmio + r_offs);
333 u32 col_cfg = readl(addr: 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(val: row_cfg, addr: kbc->mmio + r_offs);
352 writel(val: col_cfg, addr: kbc->mmio + c_offs);
353 }
354}
355
356static 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(clk: kbc->clk);
363 if (ret)
364 return ret;
365
366 /* Reset the KBC controller to clear all previous status.*/
367 reset_control_assert(rstc: kbc->rst);
368 udelay(100);
369 reset_control_deassert(rstc: kbc->rst);
370 udelay(100);
371
372 tegra_kbc_config_pins(kbc);
373 tegra_kbc_setup_wakekeys(kbc, filter: false);
374
375 writel(val: kbc->repeat_cnt, addr: 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, addr: 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(addr: kbc->mmio + KBC_INIT_DLY_0);
390 kbc->cp_dly_jiffies = usecs_to_jiffies(u: (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(addr: kbc->mmio + KBC_INT_0);
400 val >>= 4;
401 if (!val)
402 break;
403
404 val = readl(addr: kbc->mmio + KBC_KP_ENT0_0);
405 val = readl(addr: kbc->mmio + KBC_KP_ENT1_0);
406 }
407 writel(val: 0x7, addr: kbc->mmio + KBC_INT_0);
408
409 enable_irq(irq: kbc->irq);
410
411 return 0;
412}
413
414static 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(addr: kbc->mmio + KBC_CONTROL_0);
421 val &= ~1;
422 writel(val, addr: kbc->mmio + KBC_CONTROL_0);
423 spin_unlock_irqrestore(lock: &kbc->lock, flags);
424
425 disable_irq(irq: kbc->irq);
426 del_timer_sync(timer: &kbc->timer);
427
428 clk_disable_unprepare(clk: kbc->clk);
429}
430
431static 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
438static 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
445static 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
489static 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, propname: "nvidia,debounce-delay-ms", out_value: &prop))
502 kbc->debounce_cnt = prop;
503
504 if (!of_property_read_u32(np, propname: "nvidia,repeat-delay-ms", out_value: &prop))
505 kbc->repeat_cnt = prop;
506
507 kbc->use_ghost_filter = of_property_present(np, propname: "nvidia,needs-ghost-filter");
508
509 if (of_property_read_bool(np, propname: "wakeup-source") ||
510 of_property_read_bool(np, propname: "nvidia,wakeup-source")) /* legacy */
511 kbc->wakeup = true;
512
513 if (!of_get_property(node: np, name: "nvidia,kbc-row-pins", lenp: &proplen)) {
514 dev_err(kbc->dev, "property nvidia,kbc-row-pins not found\n");
515 return -ENOENT;
516 }
517 num_rows = proplen / sizeof(u32);
518
519 if (!of_get_property(node: np, name: "nvidia,kbc-col-pins", lenp: &proplen)) {
520 dev_err(kbc->dev, "property nvidia,kbc-col-pins not found\n");
521 return -ENOENT;
522 }
523 num_cols = proplen / sizeof(u32);
524
525 if (num_rows > kbc->hw_support->max_rows) {
526 dev_err(kbc->dev,
527 "Number of rows is more than supported by hardware\n");
528 return -EINVAL;
529 }
530
531 if (num_cols > kbc->hw_support->max_columns) {
532 dev_err(kbc->dev,
533 "Number of cols is more than supported by hardware\n");
534 return -EINVAL;
535 }
536
537 if (!of_get_property(node: np, name: "linux,keymap", lenp: &proplen)) {
538 dev_err(kbc->dev, "property linux,keymap not found\n");
539 return -ENOENT;
540 }
541
542 if (!num_rows || !num_cols || ((num_rows + num_cols) > KBC_MAX_GPIO)) {
543 dev_err(kbc->dev,
544 "keypad rows/columns not properly specified\n");
545 return -EINVAL;
546 }
547
548 /* Set all pins as non-configured */
549 for (i = 0; i < kbc->num_rows_and_columns; i++)
550 kbc->pin_cfg[i].type = PIN_CFG_IGNORE;
551
552 ret = of_property_read_u32_array(np, propname: "nvidia,kbc-row-pins",
553 out_values: rows_cfg, sz: num_rows);
554 if (ret < 0) {
555 dev_err(kbc->dev, "Rows configurations are not proper\n");
556 return -EINVAL;
557 }
558
559 ret = of_property_read_u32_array(np, propname: "nvidia,kbc-col-pins",
560 out_values: cols_cfg, sz: num_cols);
561 if (ret < 0) {
562 dev_err(kbc->dev, "Cols configurations are not proper\n");
563 return -EINVAL;
564 }
565
566 for (i = 0; i < num_rows; i++) {
567 kbc->pin_cfg[rows_cfg[i]].type = PIN_CFG_ROW;
568 kbc->pin_cfg[rows_cfg[i]].num = i;
569 }
570
571 for (i = 0; i < num_cols; i++) {
572 kbc->pin_cfg[cols_cfg[i]].type = PIN_CFG_COL;
573 kbc->pin_cfg[cols_cfg[i]].num = i;
574 }
575
576 return 0;
577}
578
579static const struct tegra_kbc_hw_support tegra20_kbc_hw_support = {
580 .max_rows = 16,
581 .max_columns = 8,
582};
583
584static const struct tegra_kbc_hw_support tegra11_kbc_hw_support = {
585 .max_rows = 11,
586 .max_columns = 8,
587};
588
589static const struct of_device_id tegra_kbc_of_match[] = {
590 { .compatible = "nvidia,tegra114-kbc", .data = &tegra11_kbc_hw_support},
591 { .compatible = "nvidia,tegra30-kbc", .data = &tegra20_kbc_hw_support},
592 { .compatible = "nvidia,tegra20-kbc", .data = &tegra20_kbc_hw_support},
593 { },
594};
595MODULE_DEVICE_TABLE(of, tegra_kbc_of_match);
596
597static int tegra_kbc_probe(struct platform_device *pdev)
598{
599 struct tegra_kbc *kbc;
600 int err;
601 int num_rows = 0;
602 unsigned int debounce_cnt;
603 unsigned int scan_time_rows;
604 unsigned int keymap_rows;
605 const struct of_device_id *match;
606
607 match = of_match_device(matches: tegra_kbc_of_match, dev: &pdev->dev);
608
609 kbc = devm_kzalloc(dev: &pdev->dev, size: sizeof(*kbc), GFP_KERNEL);
610 if (!kbc) {
611 dev_err(&pdev->dev, "failed to alloc memory for kbc\n");
612 return -ENOMEM;
613 }
614
615 kbc->dev = &pdev->dev;
616 kbc->hw_support = match->data;
617 kbc->max_keys = kbc->hw_support->max_rows *
618 kbc->hw_support->max_columns;
619 kbc->num_rows_and_columns = kbc->hw_support->max_rows +
620 kbc->hw_support->max_columns;
621 keymap_rows = kbc->max_keys;
622 spin_lock_init(&kbc->lock);
623
624 err = tegra_kbc_parse_dt(kbc);
625 if (err)
626 return err;
627
628 if (!tegra_kbc_check_pin_cfg(kbc, num_rows: &num_rows))
629 return -EINVAL;
630
631 kbc->irq = platform_get_irq(pdev, 0);
632 if (kbc->irq < 0)
633 return -ENXIO;
634
635 kbc->idev = devm_input_allocate_device(&pdev->dev);
636 if (!kbc->idev) {
637 dev_err(&pdev->dev, "failed to allocate input device\n");
638 return -ENOMEM;
639 }
640
641 timer_setup(&kbc->timer, tegra_kbc_keypress_timer, 0);
642
643 kbc->mmio = devm_platform_ioremap_resource(pdev, index: 0);
644 if (IS_ERR(ptr: kbc->mmio))
645 return PTR_ERR(ptr: kbc->mmio);
646
647 kbc->clk = devm_clk_get(dev: &pdev->dev, NULL);
648 if (IS_ERR(ptr: kbc->clk)) {
649 dev_err(&pdev->dev, "failed to get keyboard clock\n");
650 return PTR_ERR(ptr: kbc->clk);
651 }
652
653 kbc->rst = devm_reset_control_get(dev: &pdev->dev, id: "kbc");
654 if (IS_ERR(ptr: kbc->rst)) {
655 dev_err(&pdev->dev, "failed to get keyboard reset\n");
656 return PTR_ERR(ptr: kbc->rst);
657 }
658
659 /*
660 * The time delay between two consecutive reads of the FIFO is
661 * the sum of the repeat time and the time taken for scanning
662 * the rows. There is an additional delay before the row scanning
663 * starts. The repoll delay is computed in milliseconds.
664 */
665 debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
666 scan_time_rows = (KBC_ROW_SCAN_TIME + debounce_cnt) * num_rows;
667 kbc->repoll_dly = KBC_ROW_SCAN_DLY + scan_time_rows + kbc->repeat_cnt;
668 kbc->repoll_dly = DIV_ROUND_UP(kbc->repoll_dly, KBC_CYCLE_MS);
669
670 kbc->idev->name = pdev->name;
671 kbc->idev->id.bustype = BUS_HOST;
672 kbc->idev->dev.parent = &pdev->dev;
673 kbc->idev->open = tegra_kbc_open;
674 kbc->idev->close = tegra_kbc_close;
675
676 if (kbc->keymap_data && kbc->use_fn_map)
677 keymap_rows *= 2;
678
679 err = matrix_keypad_build_keymap(keymap_data: kbc->keymap_data, NULL,
680 rows: keymap_rows,
681 cols: kbc->hw_support->max_columns,
682 keymap: kbc->keycode, input_dev: kbc->idev);
683 if (err) {
684 dev_err(&pdev->dev, "failed to setup keymap\n");
685 return err;
686 }
687
688 __set_bit(EV_REP, kbc->idev->evbit);
689 input_set_capability(dev: kbc->idev, EV_MSC, MSC_SCAN);
690
691 input_set_drvdata(dev: kbc->idev, data: kbc);
692
693 err = devm_request_irq(dev: &pdev->dev, irq: kbc->irq, handler: tegra_kbc_isr,
694 IRQF_TRIGGER_HIGH | IRQF_NO_AUTOEN,
695 devname: pdev->name, dev_id: kbc);
696 if (err) {
697 dev_err(&pdev->dev, "failed to request keyboard IRQ\n");
698 return err;
699 }
700
701 err = input_register_device(kbc->idev);
702 if (err) {
703 dev_err(&pdev->dev, "failed to register input device\n");
704 return err;
705 }
706
707 platform_set_drvdata(pdev, data: kbc);
708 device_init_wakeup(dev: &pdev->dev, enable: kbc->wakeup);
709
710 return 0;
711}
712
713static void tegra_kbc_set_keypress_interrupt(struct tegra_kbc *kbc, bool enable)
714{
715 u32 val;
716
717 val = readl(addr: kbc->mmio + KBC_CONTROL_0);
718 if (enable)
719 val |= KBC_CONTROL_KEYPRESS_INT_EN;
720 else
721 val &= ~KBC_CONTROL_KEYPRESS_INT_EN;
722 writel(val, addr: kbc->mmio + KBC_CONTROL_0);
723}
724
725static int tegra_kbc_suspend(struct device *dev)
726{
727 struct platform_device *pdev = to_platform_device(dev);
728 struct tegra_kbc *kbc = platform_get_drvdata(pdev);
729
730 mutex_lock(&kbc->idev->mutex);
731 if (device_may_wakeup(dev: &pdev->dev)) {
732 disable_irq(irq: kbc->irq);
733 del_timer_sync(timer: &kbc->timer);
734 tegra_kbc_set_fifo_interrupt(kbc, enable: false);
735
736 /* Forcefully clear the interrupt status */
737 writel(val: 0x7, addr: kbc->mmio + KBC_INT_0);
738 /*
739 * Store the previous resident time of continuous polling mode.
740 * Force the keyboard into interrupt mode.
741 */
742 kbc->cp_to_wkup_dly = readl(addr: kbc->mmio + KBC_TO_CNT_0);
743 writel(val: 0, addr: kbc->mmio + KBC_TO_CNT_0);
744
745 tegra_kbc_setup_wakekeys(kbc, filter: true);
746 msleep(msecs: 30);
747
748 kbc->keypress_caused_wake = false;
749 /* Enable keypress interrupt before going into suspend. */
750 tegra_kbc_set_keypress_interrupt(kbc, enable: true);
751 enable_irq(irq: kbc->irq);
752 enable_irq_wake(irq: kbc->irq);
753 } else {
754 if (input_device_enabled(dev: kbc->idev))
755 tegra_kbc_stop(kbc);
756 }
757 mutex_unlock(lock: &kbc->idev->mutex);
758
759 return 0;
760}
761
762static int tegra_kbc_resume(struct device *dev)
763{
764 struct platform_device *pdev = to_platform_device(dev);
765 struct tegra_kbc *kbc = platform_get_drvdata(pdev);
766 int err = 0;
767
768 mutex_lock(&kbc->idev->mutex);
769 if (device_may_wakeup(dev: &pdev->dev)) {
770 disable_irq_wake(irq: kbc->irq);
771 tegra_kbc_setup_wakekeys(kbc, filter: false);
772 /* We will use fifo interrupts for key detection. */
773 tegra_kbc_set_keypress_interrupt(kbc, enable: false);
774
775 /* Restore the resident time of continuous polling mode. */
776 writel(val: kbc->cp_to_wkup_dly, addr: kbc->mmio + KBC_TO_CNT_0);
777
778 tegra_kbc_set_fifo_interrupt(kbc, enable: true);
779
780 if (kbc->keypress_caused_wake && kbc->wakeup_key) {
781 /*
782 * We can't report events directly from the ISR
783 * because timekeeping is stopped when processing
784 * wakeup request and we get a nasty warning when
785 * we try to call do_gettimeofday() in evdev
786 * handler.
787 */
788 input_report_key(dev: kbc->idev, code: kbc->wakeup_key, value: 1);
789 input_sync(dev: kbc->idev);
790 input_report_key(dev: kbc->idev, code: kbc->wakeup_key, value: 0);
791 input_sync(dev: kbc->idev);
792 }
793 } else {
794 if (input_device_enabled(dev: kbc->idev))
795 err = tegra_kbc_start(kbc);
796 }
797 mutex_unlock(lock: &kbc->idev->mutex);
798
799 return err;
800}
801
802static DEFINE_SIMPLE_DEV_PM_OPS(tegra_kbc_pm_ops,
803 tegra_kbc_suspend, tegra_kbc_resume);
804
805static struct platform_driver tegra_kbc_driver = {
806 .probe = tegra_kbc_probe,
807 .driver = {
808 .name = "tegra-kbc",
809 .pm = pm_sleep_ptr(&tegra_kbc_pm_ops),
810 .of_match_table = tegra_kbc_of_match,
811 },
812};
813module_platform_driver(tegra_kbc_driver);
814
815MODULE_LICENSE("GPL");
816MODULE_AUTHOR("Rakesh Iyer <riyer@nvidia.com>");
817MODULE_DESCRIPTION("Tegra matrix keyboard controller driver");
818MODULE_ALIAS("platform:tegra-kbc");
819

source code of linux/drivers/input/keyboard/tegra-kbc.c