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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * GPIO driven matrix keyboard driver
4 *
5 * Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
6 *
7 * Based on corgikbd.c
8 */
9
10#include <linux/types.h>
11#include <linux/delay.h>
12#include <linux/gpio/consumer.h>
13#include <linux/platform_device.h>
14#include <linux/input.h>
15#include <linux/irq.h>
16#include <linux/interrupt.h>
17#include <linux/jiffies.h>
18#include <linux/module.h>
19#include <linux/gpio.h>
20#include <linux/input/matrix_keypad.h>
21#include <linux/slab.h>
22#include <linux/of.h>
23#include <linux/of_gpio.h>
24#include <linux/of_platform.h>
25
26struct matrix_keypad {
27 const struct matrix_keypad_platform_data *pdata;
28 struct input_dev *input_dev;
29 unsigned int row_shift;
30
31 DECLARE_BITMAP(disabled_gpios, MATRIX_MAX_ROWS);
32
33 uint32_t last_key_state[MATRIX_MAX_COLS];
34 struct delayed_work work;
35 spinlock_t lock;
36 bool scan_pending;
37 bool stopped;
38 bool gpio_all_disabled;
39};
40
41/*
42 * NOTE: If drive_inactive_cols is false, then the GPIO has to be put into
43 * HiZ when de-activated to cause minmal side effect when scanning other
44 * columns. In that case it is configured here to be input, otherwise it is
45 * driven with the inactive value.
46 */
47static void __activate_col(const struct matrix_keypad_platform_data *pdata,
48 int col, bool on)
49{
50 bool level_on = !pdata->active_low;
51
52 if (on) {
53 gpio_direction_output(pdata->col_gpios[col], level_on);
54 } else {
55 gpio_set_value_cansleep(pdata->col_gpios[col], !level_on);
56 if (!pdata->drive_inactive_cols)
57 gpio_direction_input(pdata->col_gpios[col]);
58 }
59}
60
61static void activate_col(const struct matrix_keypad_platform_data *pdata,
62 int col, bool on)
63{
64 __activate_col(pdata, col, on);
65
66 if (on && pdata->col_scan_delay_us)
67 udelay(pdata->col_scan_delay_us);
68}
69
70static void activate_all_cols(const struct matrix_keypad_platform_data *pdata,
71 bool on)
72{
73 int col;
74
75 for (col = 0; col < pdata->num_col_gpios; col++)
76 __activate_col(pdata, col, on);
77}
78
79static bool row_asserted(const struct matrix_keypad_platform_data *pdata,
80 int row)
81{
82 return gpio_get_value_cansleep(pdata->row_gpios[row]) ?
83 !pdata->active_low : pdata->active_low;
84}
85
86static void enable_row_irqs(struct matrix_keypad *keypad)
87{
88 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
89 int i;
90
91 if (pdata->clustered_irq > 0)
92 enable_irq(pdata->clustered_irq);
93 else {
94 for (i = 0; i < pdata->num_row_gpios; i++)
95 enable_irq(gpio_to_irq(pdata->row_gpios[i]));
96 }
97}
98
99static void disable_row_irqs(struct matrix_keypad *keypad)
100{
101 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
102 int i;
103
104 if (pdata->clustered_irq > 0)
105 disable_irq_nosync(pdata->clustered_irq);
106 else {
107 for (i = 0; i < pdata->num_row_gpios; i++)
108 disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
109 }
110}
111
112/*
113 * This gets the keys from keyboard and reports it to input subsystem
114 */
115static void matrix_keypad_scan(struct work_struct *work)
116{
117 struct matrix_keypad *keypad =
118 container_of(work, struct matrix_keypad, work.work);
119 struct input_dev *input_dev = keypad->input_dev;
120 const unsigned short *keycodes = input_dev->keycode;
121 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
122 uint32_t new_state[MATRIX_MAX_COLS];
123 int row, col, code;
124
125 /* de-activate all columns for scanning */
126 activate_all_cols(pdata, false);
127
128 memset(new_state, 0, sizeof(new_state));
129
130 for (row = 0; row < pdata->num_row_gpios; row++)
131 gpio_direction_input(pdata->row_gpios[row]);
132
133 /* assert each column and read the row status out */
134 for (col = 0; col < pdata->num_col_gpios; col++) {
135
136 activate_col(pdata, col, true);
137
138 for (row = 0; row < pdata->num_row_gpios; row++)
139 new_state[col] |=
140 row_asserted(pdata, row) ? (1 << row) : 0;
141
142 activate_col(pdata, col, false);
143 }
144
145 for (col = 0; col < pdata->num_col_gpios; col++) {
146 uint32_t bits_changed;
147
148 bits_changed = keypad->last_key_state[col] ^ new_state[col];
149 if (bits_changed == 0)
150 continue;
151
152 for (row = 0; row < pdata->num_row_gpios; row++) {
153 if ((bits_changed & (1 << row)) == 0)
154 continue;
155
156 code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
157 input_event(input_dev, EV_MSC, MSC_SCAN, code);
158 input_report_key(input_dev,
159 keycodes[code],
160 new_state[col] & (1 << row));
161 }
162 }
163 input_sync(input_dev);
164
165 memcpy(keypad->last_key_state, new_state, sizeof(new_state));
166
167 activate_all_cols(pdata, true);
168
169 /* Enable IRQs again */
170 spin_lock_irq(&keypad->lock);
171 keypad->scan_pending = false;
172 enable_row_irqs(keypad);
173 spin_unlock_irq(&keypad->lock);
174}
175
176static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
177{
178 struct matrix_keypad *keypad = id;
179 unsigned long flags;
180
181 spin_lock_irqsave(&keypad->lock, flags);
182
183 /*
184 * See if another IRQ beaten us to it and scheduled the
185 * scan already. In that case we should not try to
186 * disable IRQs again.
187 */
188 if (unlikely(keypad->scan_pending || keypad->stopped))
189 goto out;
190
191 disable_row_irqs(keypad);
192 keypad->scan_pending = true;
193 schedule_delayed_work(&keypad->work,
194 msecs_to_jiffies(keypad->pdata->debounce_ms));
195
196out:
197 spin_unlock_irqrestore(&keypad->lock, flags);
198 return IRQ_HANDLED;
199}
200
201static int matrix_keypad_start(struct input_dev *dev)
202{
203 struct matrix_keypad *keypad = input_get_drvdata(dev);
204
205 keypad->stopped = false;
206 mb();
207
208 /*
209 * Schedule an immediate key scan to capture current key state;
210 * columns will be activated and IRQs be enabled after the scan.
211 */
212 schedule_delayed_work(&keypad->work, 0);
213
214 return 0;
215}
216
217static void matrix_keypad_stop(struct input_dev *dev)
218{
219 struct matrix_keypad *keypad = input_get_drvdata(dev);
220
221 spin_lock_irq(&keypad->lock);
222 keypad->stopped = true;
223 spin_unlock_irq(&keypad->lock);
224
225 flush_delayed_work(&keypad->work);
226 /*
227 * matrix_keypad_scan() will leave IRQs enabled;
228 * we should disable them now.
229 */
230 disable_row_irqs(keypad);
231}
232
233static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
234{
235 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
236 unsigned int gpio;
237 int i;
238
239 if (pdata->clustered_irq > 0) {
240 if (enable_irq_wake(pdata->clustered_irq) == 0)
241 keypad->gpio_all_disabled = true;
242 } else {
243
244 for (i = 0; i < pdata->num_row_gpios; i++) {
245 if (!test_bit(i, keypad->disabled_gpios)) {
246 gpio = pdata->row_gpios[i];
247
248 if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
249 __set_bit(i, keypad->disabled_gpios);
250 }
251 }
252 }
253}
254
255static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
256{
257 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
258 unsigned int gpio;
259 int i;
260
261 if (pdata->clustered_irq > 0) {
262 if (keypad->gpio_all_disabled) {
263 disable_irq_wake(pdata->clustered_irq);
264 keypad->gpio_all_disabled = false;
265 }
266 } else {
267 for (i = 0; i < pdata->num_row_gpios; i++) {
268 if (test_and_clear_bit(i, keypad->disabled_gpios)) {
269 gpio = pdata->row_gpios[i];
270 disable_irq_wake(gpio_to_irq(gpio));
271 }
272 }
273 }
274}
275
276static int matrix_keypad_suspend(struct device *dev)
277{
278 struct platform_device *pdev = to_platform_device(dev);
279 struct matrix_keypad *keypad = platform_get_drvdata(pdev);
280
281 matrix_keypad_stop(keypad->input_dev);
282
283 if (device_may_wakeup(&pdev->dev))
284 matrix_keypad_enable_wakeup(keypad);
285
286 return 0;
287}
288
289static int matrix_keypad_resume(struct device *dev)
290{
291 struct platform_device *pdev = to_platform_device(dev);
292 struct matrix_keypad *keypad = platform_get_drvdata(pdev);
293
294 if (device_may_wakeup(&pdev->dev))
295 matrix_keypad_disable_wakeup(keypad);
296
297 matrix_keypad_start(keypad->input_dev);
298
299 return 0;
300}
301
302static DEFINE_SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
303 matrix_keypad_suspend, matrix_keypad_resume);
304
305static int matrix_keypad_init_gpio(struct platform_device *pdev,
306 struct matrix_keypad *keypad)
307{
308 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
309 int i, err;
310
311 /* initialized strobe lines as outputs, activated */
312 for (i = 0; i < pdata->num_col_gpios; i++) {
313 err = gpio_request(pdata->col_gpios[i], "matrix_kbd_col");
314 if (err) {
315 dev_err(&pdev->dev,
316 "failed to request GPIO%d for COL%d\n",
317 pdata->col_gpios[i], i);
318 goto err_free_cols;
319 }
320
321 gpio_direction_output(pdata->col_gpios[i], !pdata->active_low);
322 }
323
324 for (i = 0; i < pdata->num_row_gpios; i++) {
325 err = gpio_request(pdata->row_gpios[i], "matrix_kbd_row");
326 if (err) {
327 dev_err(&pdev->dev,
328 "failed to request GPIO%d for ROW%d\n",
329 pdata->row_gpios[i], i);
330 goto err_free_rows;
331 }
332
333 gpio_direction_input(pdata->row_gpios[i]);
334 }
335
336 if (pdata->clustered_irq > 0) {
337 err = request_any_context_irq(pdata->clustered_irq,
338 matrix_keypad_interrupt,
339 pdata->clustered_irq_flags,
340 "matrix-keypad", keypad);
341 if (err < 0) {
342 dev_err(&pdev->dev,
343 "Unable to acquire clustered interrupt\n");
344 goto err_free_rows;
345 }
346 } else {
347 for (i = 0; i < pdata->num_row_gpios; i++) {
348 err = request_any_context_irq(
349 gpio_to_irq(pdata->row_gpios[i]),
350 matrix_keypad_interrupt,
351 IRQF_TRIGGER_RISING |
352 IRQF_TRIGGER_FALLING,
353 "matrix-keypad", keypad);
354 if (err < 0) {
355 dev_err(&pdev->dev,
356 "Unable to acquire interrupt for GPIO line %i\n",
357 pdata->row_gpios[i]);
358 goto err_free_irqs;
359 }
360 }
361 }
362
363 /* initialized as disabled - enabled by input->open */
364 disable_row_irqs(keypad);
365 return 0;
366
367err_free_irqs:
368 while (--i >= 0)
369 free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
370 i = pdata->num_row_gpios;
371err_free_rows:
372 while (--i >= 0)
373 gpio_free(pdata->row_gpios[i]);
374 i = pdata->num_col_gpios;
375err_free_cols:
376 while (--i >= 0)
377 gpio_free(pdata->col_gpios[i]);
378
379 return err;
380}
381
382static void matrix_keypad_free_gpio(struct matrix_keypad *keypad)
383{
384 const struct matrix_keypad_platform_data *pdata = keypad->pdata;
385 int i;
386
387 if (pdata->clustered_irq > 0) {
388 free_irq(pdata->clustered_irq, keypad);
389 } else {
390 for (i = 0; i < pdata->num_row_gpios; i++)
391 free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
392 }
393
394 for (i = 0; i < pdata->num_row_gpios; i++)
395 gpio_free(pdata->row_gpios[i]);
396
397 for (i = 0; i < pdata->num_col_gpios; i++)
398 gpio_free(pdata->col_gpios[i]);
399}
400
401#ifdef CONFIG_OF
402static struct matrix_keypad_platform_data *
403matrix_keypad_parse_dt(struct device *dev)
404{
405 struct matrix_keypad_platform_data *pdata;
406 struct device_node *np = dev->of_node;
407 unsigned int *gpios;
408 int ret, i, nrow, ncol;
409
410 if (!np) {
411 dev_err(dev, "device lacks DT data\n");
412 return ERR_PTR(-ENODEV);
413 }
414
415 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
416 if (!pdata) {
417 dev_err(dev, "could not allocate memory for platform data\n");
418 return ERR_PTR(-ENOMEM);
419 }
420
421 pdata->num_row_gpios = nrow = gpiod_count(dev, "row");
422 pdata->num_col_gpios = ncol = gpiod_count(dev, "col");
423 if (nrow < 0 || ncol < 0) {
424 dev_err(dev, "number of keypad rows/columns not specified\n");
425 return ERR_PTR(-EINVAL);
426 }
427
428 if (of_get_property(np, "linux,no-autorepeat", NULL))
429 pdata->no_autorepeat = true;
430
431 pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
432 of_property_read_bool(np, "linux,wakeup"); /* legacy */
433
434 if (of_get_property(np, "gpio-activelow", NULL))
435 pdata->active_low = true;
436
437 pdata->drive_inactive_cols =
438 of_property_read_bool(np, "drive-inactive-cols");
439
440 of_property_read_u32(np, "debounce-delay-ms", &pdata->debounce_ms);
441 of_property_read_u32(np, "col-scan-delay-us",
442 &pdata->col_scan_delay_us);
443
444 gpios = devm_kcalloc(dev,
445 pdata->num_row_gpios + pdata->num_col_gpios,
446 sizeof(unsigned int),
447 GFP_KERNEL);
448 if (!gpios) {
449 dev_err(dev, "could not allocate memory for gpios\n");
450 return ERR_PTR(-ENOMEM);
451 }
452
453 for (i = 0; i < nrow; i++) {
454 ret = of_get_named_gpio(np, "row-gpios", i);
455 if (ret < 0)
456 return ERR_PTR(ret);
457 gpios[i] = ret;
458 }
459
460 for (i = 0; i < ncol; i++) {
461 ret = of_get_named_gpio(np, "col-gpios", i);
462 if (ret < 0)
463 return ERR_PTR(ret);
464 gpios[nrow + i] = ret;
465 }
466
467 pdata->row_gpios = gpios;
468 pdata->col_gpios = &gpios[pdata->num_row_gpios];
469
470 return pdata;
471}
472#else
473static inline struct matrix_keypad_platform_data *
474matrix_keypad_parse_dt(struct device *dev)
475{
476 dev_err(dev, "no platform data defined\n");
477
478 return ERR_PTR(-EINVAL);
479}
480#endif
481
482static int matrix_keypad_probe(struct platform_device *pdev)
483{
484 const struct matrix_keypad_platform_data *pdata;
485 struct matrix_keypad *keypad;
486 struct input_dev *input_dev;
487 int err;
488
489 pdata = dev_get_platdata(&pdev->dev);
490 if (!pdata) {
491 pdata = matrix_keypad_parse_dt(&pdev->dev);
492 if (IS_ERR(pdata))
493 return PTR_ERR(pdata);
494 } else if (!pdata->keymap_data) {
495 dev_err(&pdev->dev, "no keymap data defined\n");
496 return -EINVAL;
497 }
498
499 keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
500 input_dev = input_allocate_device();
501 if (!keypad || !input_dev) {
502 err = -ENOMEM;
503 goto err_free_mem;
504 }
505
506 keypad->input_dev = input_dev;
507 keypad->pdata = pdata;
508 keypad->row_shift = get_count_order(pdata->num_col_gpios);
509 keypad->stopped = true;
510 INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
511 spin_lock_init(&keypad->lock);
512
513 input_dev->name = pdev->name;
514 input_dev->id.bustype = BUS_HOST;
515 input_dev->dev.parent = &pdev->dev;
516 input_dev->open = matrix_keypad_start;
517 input_dev->close = matrix_keypad_stop;
518
519 err = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
520 pdata->num_row_gpios,
521 pdata->num_col_gpios,
522 NULL, input_dev);
523 if (err) {
524 dev_err(&pdev->dev, "failed to build keymap\n");
525 goto err_free_mem;
526 }
527
528 if (!pdata->no_autorepeat)
529 __set_bit(EV_REP, input_dev->evbit);
530 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
531 input_set_drvdata(input_dev, keypad);
532
533 err = matrix_keypad_init_gpio(pdev, keypad);
534 if (err)
535 goto err_free_mem;
536
537 err = input_register_device(keypad->input_dev);
538 if (err)
539 goto err_free_gpio;
540
541 device_init_wakeup(&pdev->dev, pdata->wakeup);
542 platform_set_drvdata(pdev, keypad);
543
544 return 0;
545
546err_free_gpio:
547 matrix_keypad_free_gpio(keypad);
548err_free_mem:
549 input_free_device(input_dev);
550 kfree(keypad);
551 return err;
552}
553
554static int matrix_keypad_remove(struct platform_device *pdev)
555{
556 struct matrix_keypad *keypad = platform_get_drvdata(pdev);
557
558 matrix_keypad_free_gpio(keypad);
559 input_unregister_device(keypad->input_dev);
560 kfree(keypad);
561
562 return 0;
563}
564
565#ifdef CONFIG_OF
566static const struct of_device_id matrix_keypad_dt_match[] = {
567 { .compatible = "gpio-matrix-keypad" },
568 { }
569};
570MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
571#endif
572
573static struct platform_driver matrix_keypad_driver = {
574 .probe = matrix_keypad_probe,
575 .remove = matrix_keypad_remove,
576 .driver = {
577 .name = "matrix-keypad",
578 .pm = pm_sleep_ptr(&matrix_keypad_pm_ops),
579 .of_match_table = of_match_ptr(matrix_keypad_dt_match),
580 },
581};
582module_platform_driver(matrix_keypad_driver);
583
584MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
585MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
586MODULE_LICENSE("GPL v2");
587MODULE_ALIAS("platform:matrix-keypad");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * GPIO driven matrix keyboard driver
4 *
5 * Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
6 *
7 * Based on corgikbd.c
8 */
9
10#include <linux/types.h>
11#include <linux/delay.h>
12#include <linux/gpio/consumer.h>
13#include <linux/platform_device.h>
14#include <linux/input.h>
15#include <linux/irq.h>
16#include <linux/interrupt.h>
17#include <linux/jiffies.h>
18#include <linux/module.h>
19#include <linux/gpio.h>
20#include <linux/input/matrix_keypad.h>
21#include <linux/slab.h>
22#include <linux/of.h>
23
24struct matrix_keypad {
25 struct input_dev *input_dev;
26 unsigned int row_shift;
27
28 unsigned int col_scan_delay_us;
29 /* key debounce interval in milli-second */
30 unsigned int debounce_ms;
31 bool drive_inactive_cols;
32
33 struct gpio_desc *row_gpios[MATRIX_MAX_ROWS];
34 unsigned int num_row_gpios;
35
36 struct gpio_desc *col_gpios[MATRIX_MAX_ROWS];
37 unsigned int num_col_gpios;
38
39 unsigned int row_irqs[MATRIX_MAX_ROWS];
40 DECLARE_BITMAP(wakeup_enabled_irqs, MATRIX_MAX_ROWS);
41
42 uint32_t last_key_state[MATRIX_MAX_COLS];
43 struct delayed_work work;
44 spinlock_t lock;
45 bool scan_pending;
46 bool stopped;
47};
48
49/*
50 * NOTE: If drive_inactive_cols is false, then the GPIO has to be put into
51 * HiZ when de-activated to cause minmal side effect when scanning other
52 * columns. In that case it is configured here to be input, otherwise it is
53 * driven with the inactive value.
54 */
55static void __activate_col(struct matrix_keypad *keypad, int col, bool on)
56{
57 if (on) {
58 gpiod_direction_output(keypad->col_gpios[col], 1);
59 } else {
60 gpiod_set_value_cansleep(keypad->col_gpios[col], 0);
61 if (!keypad->drive_inactive_cols)
62 gpiod_direction_input(keypad->col_gpios[col]);
63 }
64}
65
66static void activate_col(struct matrix_keypad *keypad, int col, bool on)
67{
68 __activate_col(keypad, col, on);
69
70 if (on && keypad->col_scan_delay_us)
71 udelay(keypad->col_scan_delay_us);
72}
73
74static void activate_all_cols(struct matrix_keypad *keypad, bool on)
75{
76 int col;
77
78 for (col = 0; col < keypad->num_col_gpios; col++)
79 __activate_col(keypad, col, on);
80}
81
82static bool row_asserted(struct matrix_keypad *keypad, int row)
83{
84 return gpiod_get_value_cansleep(keypad->row_gpios[row]);
85}
86
87static void enable_row_irqs(struct matrix_keypad *keypad)
88{
89 int i;
90
91 for (i = 0; i < keypad->num_row_gpios; i++)
92 enable_irq(keypad->row_irqs[i]);
93}
94
95static void disable_row_irqs(struct matrix_keypad *keypad)
96{
97 int i;
98
99 for (i = 0; i < keypad->num_row_gpios; i++)
100 disable_irq_nosync(keypad->row_irqs[i]);
101}
102
103/*
104 * This gets the keys from keyboard and reports it to input subsystem
105 */
106static void matrix_keypad_scan(struct work_struct *work)
107{
108 struct matrix_keypad *keypad =
109 container_of(work, struct matrix_keypad, work.work);
110 struct input_dev *input_dev = keypad->input_dev;
111 const unsigned short *keycodes = input_dev->keycode;
112 uint32_t new_state[MATRIX_MAX_COLS];
113 int row, col, code;
114
115 /* de-activate all columns for scanning */
116 activate_all_cols(keypad, false);
117
118 memset(new_state, 0, sizeof(new_state));
119
120 for (row = 0; row < keypad->num_row_gpios; row++)
121 gpiod_direction_input(keypad->row_gpios[row]);
122
123 /* assert each column and read the row status out */
124 for (col = 0; col < keypad->num_col_gpios; col++) {
125
126 activate_col(keypad, col, true);
127
128 for (row = 0; row < keypad->num_row_gpios; row++)
129 new_state[col] |=
130 row_asserted(keypad, row) ? BIT(row) : 0;
131
132 activate_col(keypad, col, false);
133 }
134
135 for (col = 0; col < keypad->num_col_gpios; col++) {
136 uint32_t bits_changed;
137
138 bits_changed = keypad->last_key_state[col] ^ new_state[col];
139 if (bits_changed == 0)
140 continue;
141
142 for (row = 0; row < keypad->num_row_gpios; row++) {
143 if (!(bits_changed & BIT(row)))
144 continue;
145
146 code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
147 input_event(input_dev, EV_MSC, MSC_SCAN, code);
148 input_report_key(input_dev,
149 keycodes[code],
150 new_state[col] & (1 << row));
151 }
152 }
153 input_sync(input_dev);
154
155 memcpy(keypad->last_key_state, new_state, sizeof(new_state));
156
157 activate_all_cols(keypad, true);
158
159 /* Enable IRQs again */
160 scoped_guard(spinlock_irq, &keypad->lock) {
161 keypad->scan_pending = false;
162 enable_row_irqs(keypad);
163 }
164}
165
166static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
167{
168 struct matrix_keypad *keypad = id;
169
170 guard(spinlock_irqsave)(&keypad->lock);
171
172 /*
173 * See if another IRQ beaten us to it and scheduled the
174 * scan already. In that case we should not try to
175 * disable IRQs again.
176 */
177 if (unlikely(keypad->scan_pending || keypad->stopped))
178 goto out;
179
180 disable_row_irqs(keypad);
181 keypad->scan_pending = true;
182 schedule_delayed_work(&keypad->work,
183 msecs_to_jiffies(keypad->debounce_ms));
184
185out:
186 return IRQ_HANDLED;
187}
188
189static int matrix_keypad_start(struct input_dev *dev)
190{
191 struct matrix_keypad *keypad = input_get_drvdata(dev);
192
193 keypad->stopped = false;
194 mb();
195
196 /*
197 * Schedule an immediate key scan to capture current key state;
198 * columns will be activated and IRQs be enabled after the scan.
199 */
200 schedule_delayed_work(&keypad->work, 0);
201
202 return 0;
203}
204
205static void matrix_keypad_stop(struct input_dev *dev)
206{
207 struct matrix_keypad *keypad = input_get_drvdata(dev);
208
209 scoped_guard(spinlock_irq, &keypad->lock) {
210 keypad->stopped = true;
211 }
212
213 flush_delayed_work(&keypad->work);
214 /*
215 * matrix_keypad_scan() will leave IRQs enabled;
216 * we should disable them now.
217 */
218 disable_row_irqs(keypad);
219}
220
221static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
222{
223 int i;
224
225 for_each_clear_bit(i, keypad->wakeup_enabled_irqs,
226 keypad->num_row_gpios)
227 if (enable_irq_wake(keypad->row_irqs[i]) == 0)
228 __set_bit(i, keypad->wakeup_enabled_irqs);
229}
230
231static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
232{
233 int i;
234
235 for_each_set_bit(i, keypad->wakeup_enabled_irqs,
236 keypad->num_row_gpios) {
237 disable_irq_wake(keypad->row_irqs[i]);
238 __clear_bit(i, keypad->wakeup_enabled_irqs);
239 }
240}
241
242static int matrix_keypad_suspend(struct device *dev)
243{
244 struct platform_device *pdev = to_platform_device(dev);
245 struct matrix_keypad *keypad = platform_get_drvdata(pdev);
246
247 matrix_keypad_stop(keypad->input_dev);
248
249 if (device_may_wakeup(&pdev->dev))
250 matrix_keypad_enable_wakeup(keypad);
251
252 return 0;
253}
254
255static int matrix_keypad_resume(struct device *dev)
256{
257 struct platform_device *pdev = to_platform_device(dev);
258 struct matrix_keypad *keypad = platform_get_drvdata(pdev);
259
260 if (device_may_wakeup(&pdev->dev))
261 matrix_keypad_disable_wakeup(keypad);
262
263 matrix_keypad_start(keypad->input_dev);
264
265 return 0;
266}
267
268static DEFINE_SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
269 matrix_keypad_suspend, matrix_keypad_resume);
270
271static int matrix_keypad_init_gpio(struct platform_device *pdev,
272 struct matrix_keypad *keypad)
273{
274 bool active_low;
275 int nrow, ncol;
276 int err;
277 int i;
278
279 nrow = gpiod_count(&pdev->dev, "row");
280 ncol = gpiod_count(&pdev->dev, "col");
281 if (nrow < 0 || ncol < 0) {
282 dev_err(&pdev->dev, "missing row or column GPIOs\n");
283 return -EINVAL;
284 }
285
286 keypad->num_row_gpios = nrow;
287 keypad->num_col_gpios = ncol;
288
289 active_low = device_property_read_bool(&pdev->dev, "gpio-activelow");
290
291 /* initialize strobe lines as outputs, activated */
292 for (i = 0; i < keypad->num_col_gpios; i++) {
293 keypad->col_gpios[i] = devm_gpiod_get_index(&pdev->dev, "col",
294 i, GPIOD_ASIS);
295 err = PTR_ERR_OR_ZERO(keypad->col_gpios[i]);
296 if (err) {
297 dev_err(&pdev->dev,
298 "failed to request GPIO for COL%d: %d\n",
299 i, err);
300 return err;
301 }
302
303 gpiod_set_consumer_name(keypad->col_gpios[i], "matrix_kbd_col");
304
305 if (active_low ^ gpiod_is_active_low(keypad->col_gpios[i]))
306 gpiod_toggle_active_low(keypad->col_gpios[i]);
307
308 gpiod_direction_output(keypad->col_gpios[i], 1);
309 }
310
311 for (i = 0; i < keypad->num_row_gpios; i++) {
312 keypad->row_gpios[i] = devm_gpiod_get_index(&pdev->dev, "row",
313 i, GPIOD_IN);
314 err = PTR_ERR_OR_ZERO(keypad->row_gpios[i]);
315 if (err) {
316 dev_err(&pdev->dev,
317 "failed to request GPIO for ROW%d: %d\n",
318 i, err);
319 return err;
320 }
321
322 gpiod_set_consumer_name(keypad->row_gpios[i], "matrix_kbd_row");
323
324 if (active_low ^ gpiod_is_active_low(keypad->row_gpios[i]))
325 gpiod_toggle_active_low(keypad->row_gpios[i]);
326 }
327
328 return 0;
329}
330
331static int matrix_keypad_setup_interrupts(struct platform_device *pdev,
332 struct matrix_keypad *keypad)
333{
334 int err;
335 int irq;
336 int i;
337
338 for (i = 0; i < keypad->num_row_gpios; i++) {
339 irq = gpiod_to_irq(keypad->row_gpios[i]);
340 if (irq < 0) {
341 err = irq;
342 dev_err(&pdev->dev,
343 "Unable to convert GPIO line %i to irq: %d\n",
344 i, err);
345 return err;
346 }
347
348 err = devm_request_any_context_irq(&pdev->dev, irq,
349 matrix_keypad_interrupt,
350 IRQF_TRIGGER_RISING |
351 IRQF_TRIGGER_FALLING,
352 "matrix-keypad", keypad);
353 if (err < 0) {
354 dev_err(&pdev->dev,
355 "Unable to acquire interrupt for row %i: %d\n",
356 i, err);
357 return err;
358 }
359
360 keypad->row_irqs[i] = irq;
361 }
362
363 /* initialized as disabled - enabled by input->open */
364 disable_row_irqs(keypad);
365
366 return 0;
367}
368
369static int matrix_keypad_probe(struct platform_device *pdev)
370{
371 struct matrix_keypad *keypad;
372 struct input_dev *input_dev;
373 bool wakeup;
374 int err;
375
376 keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
377 if (!keypad)
378 return -ENOMEM;
379
380 input_dev = devm_input_allocate_device(&pdev->dev);
381 if (!input_dev)
382 return -ENOMEM;
383
384 keypad->input_dev = input_dev;
385 keypad->stopped = true;
386 INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
387 spin_lock_init(&keypad->lock);
388
389 keypad->drive_inactive_cols =
390 device_property_read_bool(&pdev->dev, "drive-inactive-cols");
391 device_property_read_u32(&pdev->dev, "debounce-delay-ms",
392 &keypad->debounce_ms);
393 device_property_read_u32(&pdev->dev, "col-scan-delay-us",
394 &keypad->col_scan_delay_us);
395
396 err = matrix_keypad_init_gpio(pdev, keypad);
397 if (err)
398 return err;
399
400 keypad->row_shift = get_count_order(keypad->num_col_gpios);
401
402 err = matrix_keypad_setup_interrupts(pdev, keypad);
403 if (err)
404 return err;
405
406 input_dev->name = pdev->name;
407 input_dev->id.bustype = BUS_HOST;
408 input_dev->open = matrix_keypad_start;
409 input_dev->close = matrix_keypad_stop;
410
411 err = matrix_keypad_build_keymap(NULL, NULL,
412 keypad->num_row_gpios,
413 keypad->num_col_gpios,
414 NULL, input_dev);
415 if (err) {
416 dev_err(&pdev->dev, "failed to build keymap\n");
417 return -ENOMEM;
418 }
419
420 if (!device_property_read_bool(&pdev->dev, "linux,no-autorepeat"))
421 __set_bit(EV_REP, input_dev->evbit);
422
423 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
424 input_set_drvdata(input_dev, keypad);
425
426 err = input_register_device(keypad->input_dev);
427 if (err)
428 return err;
429
430 wakeup = device_property_read_bool(&pdev->dev, "wakeup-source") ||
431 /* legacy */
432 device_property_read_bool(&pdev->dev, "linux,wakeup");
433 device_init_wakeup(&pdev->dev, wakeup);
434
435 platform_set_drvdata(pdev, keypad);
436
437 return 0;
438}
439
440#ifdef CONFIG_OF
441static const struct of_device_id matrix_keypad_dt_match[] = {
442 { .compatible = "gpio-matrix-keypad" },
443 { }
444};
445MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
446#endif
447
448static struct platform_driver matrix_keypad_driver = {
449 .probe = matrix_keypad_probe,
450 .driver = {
451 .name = "matrix-keypad",
452 .pm = pm_sleep_ptr(&matrix_keypad_pm_ops),
453 .of_match_table = of_match_ptr(matrix_keypad_dt_match),
454 },
455};
456module_platform_driver(matrix_keypad_driver);
457
458MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
459MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
460MODULE_LICENSE("GPL v2");
461MODULE_ALIAS("platform:matrix-keypad");