Linux Audio

Check our new training course

Loading...
v6.2
  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");
v4.17
 
  1/*
  2 *  GPIO driven matrix keyboard driver
  3 *
  4 *  Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
  5 *
  6 *  Based on corgikbd.c
  7 *
  8 *  This program is free software; you can redistribute it and/or modify
  9 *  it under the terms of the GNU General Public License version 2 as
 10 *  published by the Free Software Foundation.
 11 *
 12 */
 13
 14#include <linux/types.h>
 15#include <linux/delay.h>
 
 16#include <linux/platform_device.h>
 17#include <linux/input.h>
 18#include <linux/irq.h>
 19#include <linux/interrupt.h>
 20#include <linux/jiffies.h>
 21#include <linux/module.h>
 22#include <linux/gpio.h>
 23#include <linux/input/matrix_keypad.h>
 24#include <linux/slab.h>
 25#include <linux/of.h>
 26#include <linux/of_gpio.h>
 27#include <linux/of_platform.h>
 28
 29struct matrix_keypad {
 30	const struct matrix_keypad_platform_data *pdata;
 31	struct input_dev *input_dev;
 32	unsigned int row_shift;
 33
 34	DECLARE_BITMAP(disabled_gpios, MATRIX_MAX_ROWS);
 35
 36	uint32_t last_key_state[MATRIX_MAX_COLS];
 37	struct delayed_work work;
 38	spinlock_t lock;
 39	bool scan_pending;
 40	bool stopped;
 41	bool gpio_all_disabled;
 42};
 43
 44/*
 45 * NOTE: If drive_inactive_cols is false, then the GPIO has to be put into
 46 * HiZ when de-activated to cause minmal side effect when scanning other
 47 * columns. In that case it is configured here to be input, otherwise it is
 48 * driven with the inactive value.
 49 */
 50static void __activate_col(const struct matrix_keypad_platform_data *pdata,
 51			   int col, bool on)
 52{
 53	bool level_on = !pdata->active_low;
 54
 55	if (on) {
 56		gpio_direction_output(pdata->col_gpios[col], level_on);
 57	} else {
 58		gpio_set_value_cansleep(pdata->col_gpios[col], !level_on);
 59		if (!pdata->drive_inactive_cols)
 60			gpio_direction_input(pdata->col_gpios[col]);
 61	}
 62}
 63
 64static void activate_col(const struct matrix_keypad_platform_data *pdata,
 65			 int col, bool on)
 66{
 67	__activate_col(pdata, col, on);
 68
 69	if (on && pdata->col_scan_delay_us)
 70		udelay(pdata->col_scan_delay_us);
 71}
 72
 73static void activate_all_cols(const struct matrix_keypad_platform_data *pdata,
 74			      bool on)
 75{
 76	int col;
 77
 78	for (col = 0; col < pdata->num_col_gpios; col++)
 79		__activate_col(pdata, col, on);
 80}
 81
 82static bool row_asserted(const struct matrix_keypad_platform_data *pdata,
 83			 int row)
 84{
 85	return gpio_get_value_cansleep(pdata->row_gpios[row]) ?
 86			!pdata->active_low : pdata->active_low;
 87}
 88
 89static void enable_row_irqs(struct matrix_keypad *keypad)
 90{
 91	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
 92	int i;
 93
 94	if (pdata->clustered_irq > 0)
 95		enable_irq(pdata->clustered_irq);
 96	else {
 97		for (i = 0; i < pdata->num_row_gpios; i++)
 98			enable_irq(gpio_to_irq(pdata->row_gpios[i]));
 99	}
100}
101
102static void disable_row_irqs(struct matrix_keypad *keypad)
103{
104	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
105	int i;
106
107	if (pdata->clustered_irq > 0)
108		disable_irq_nosync(pdata->clustered_irq);
109	else {
110		for (i = 0; i < pdata->num_row_gpios; i++)
111			disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
112	}
113}
114
115/*
116 * This gets the keys from keyboard and reports it to input subsystem
117 */
118static void matrix_keypad_scan(struct work_struct *work)
119{
120	struct matrix_keypad *keypad =
121		container_of(work, struct matrix_keypad, work.work);
122	struct input_dev *input_dev = keypad->input_dev;
123	const unsigned short *keycodes = input_dev->keycode;
124	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
125	uint32_t new_state[MATRIX_MAX_COLS];
126	int row, col, code;
127
128	/* de-activate all columns for scanning */
129	activate_all_cols(pdata, false);
130
131	memset(new_state, 0, sizeof(new_state));
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_work(&keypad->work.work);
226	/*
227	 * matrix_keypad_scan() will leave IRQs enabled;
228	 * we should disable them now.
229	 */
230	disable_row_irqs(keypad);
231}
232
233#ifdef CONFIG_PM_SLEEP
234static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
235{
236	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
237	unsigned int gpio;
238	int i;
239
240	if (pdata->clustered_irq > 0) {
241		if (enable_irq_wake(pdata->clustered_irq) == 0)
242			keypad->gpio_all_disabled = true;
243	} else {
244
245		for (i = 0; i < pdata->num_row_gpios; i++) {
246			if (!test_bit(i, keypad->disabled_gpios)) {
247				gpio = pdata->row_gpios[i];
248
249				if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
250					__set_bit(i, keypad->disabled_gpios);
251			}
252		}
253	}
254}
255
256static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
257{
258	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
259	unsigned int gpio;
260	int i;
261
262	if (pdata->clustered_irq > 0) {
263		if (keypad->gpio_all_disabled) {
264			disable_irq_wake(pdata->clustered_irq);
265			keypad->gpio_all_disabled = false;
266		}
267	} else {
268		for (i = 0; i < pdata->num_row_gpios; i++) {
269			if (test_and_clear_bit(i, keypad->disabled_gpios)) {
270				gpio = pdata->row_gpios[i];
271				disable_irq_wake(gpio_to_irq(gpio));
272			}
273		}
274	}
275}
276
277static int matrix_keypad_suspend(struct device *dev)
278{
279	struct platform_device *pdev = to_platform_device(dev);
280	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
281
282	matrix_keypad_stop(keypad->input_dev);
283
284	if (device_may_wakeup(&pdev->dev))
285		matrix_keypad_enable_wakeup(keypad);
286
287	return 0;
288}
289
290static int matrix_keypad_resume(struct device *dev)
291{
292	struct platform_device *pdev = to_platform_device(dev);
293	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
294
295	if (device_may_wakeup(&pdev->dev))
296		matrix_keypad_disable_wakeup(keypad);
297
298	matrix_keypad_start(keypad->input_dev);
299
300	return 0;
301}
302#endif
303
304static SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
305			 matrix_keypad_suspend, matrix_keypad_resume);
306
307static int matrix_keypad_init_gpio(struct platform_device *pdev,
308				   struct matrix_keypad *keypad)
309{
310	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
311	int i, err;
312
313	/* initialized strobe lines as outputs, activated */
314	for (i = 0; i < pdata->num_col_gpios; i++) {
315		err = gpio_request(pdata->col_gpios[i], "matrix_kbd_col");
316		if (err) {
317			dev_err(&pdev->dev,
318				"failed to request GPIO%d for COL%d\n",
319				pdata->col_gpios[i], i);
320			goto err_free_cols;
321		}
322
323		gpio_direction_output(pdata->col_gpios[i], !pdata->active_low);
324	}
325
326	for (i = 0; i < pdata->num_row_gpios; i++) {
327		err = gpio_request(pdata->row_gpios[i], "matrix_kbd_row");
328		if (err) {
329			dev_err(&pdev->dev,
330				"failed to request GPIO%d for ROW%d\n",
331				pdata->row_gpios[i], i);
332			goto err_free_rows;
333		}
334
335		gpio_direction_input(pdata->row_gpios[i]);
336	}
337
338	if (pdata->clustered_irq > 0) {
339		err = request_any_context_irq(pdata->clustered_irq,
340				matrix_keypad_interrupt,
341				pdata->clustered_irq_flags,
342				"matrix-keypad", keypad);
343		if (err < 0) {
344			dev_err(&pdev->dev,
345				"Unable to acquire clustered interrupt\n");
346			goto err_free_rows;
347		}
348	} else {
349		for (i = 0; i < pdata->num_row_gpios; i++) {
350			err = request_any_context_irq(
351					gpio_to_irq(pdata->row_gpios[i]),
352					matrix_keypad_interrupt,
353					IRQF_TRIGGER_RISING |
354					IRQF_TRIGGER_FALLING,
355					"matrix-keypad", keypad);
356			if (err < 0) {
357				dev_err(&pdev->dev,
358					"Unable to acquire interrupt for GPIO line %i\n",
359					pdata->row_gpios[i]);
360				goto err_free_irqs;
361			}
362		}
363	}
364
365	/* initialized as disabled - enabled by input->open */
366	disable_row_irqs(keypad);
367	return 0;
368
369err_free_irqs:
370	while (--i >= 0)
371		free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
372	i = pdata->num_row_gpios;
373err_free_rows:
374	while (--i >= 0)
375		gpio_free(pdata->row_gpios[i]);
376	i = pdata->num_col_gpios;
377err_free_cols:
378	while (--i >= 0)
379		gpio_free(pdata->col_gpios[i]);
380
381	return err;
382}
383
384static void matrix_keypad_free_gpio(struct matrix_keypad *keypad)
385{
386	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
387	int i;
388
389	if (pdata->clustered_irq > 0) {
390		free_irq(pdata->clustered_irq, keypad);
391	} else {
392		for (i = 0; i < pdata->num_row_gpios; i++)
393			free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
394	}
395
396	for (i = 0; i < pdata->num_row_gpios; i++)
397		gpio_free(pdata->row_gpios[i]);
398
399	for (i = 0; i < pdata->num_col_gpios; i++)
400		gpio_free(pdata->col_gpios[i]);
401}
402
403#ifdef CONFIG_OF
404static struct matrix_keypad_platform_data *
405matrix_keypad_parse_dt(struct device *dev)
406{
407	struct matrix_keypad_platform_data *pdata;
408	struct device_node *np = dev->of_node;
409	unsigned int *gpios;
410	int i, nrow, ncol;
411
412	if (!np) {
413		dev_err(dev, "device lacks DT data\n");
414		return ERR_PTR(-ENODEV);
415	}
416
417	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
418	if (!pdata) {
419		dev_err(dev, "could not allocate memory for platform data\n");
420		return ERR_PTR(-ENOMEM);
421	}
422
423	pdata->num_row_gpios = nrow = of_gpio_named_count(np, "row-gpios");
424	pdata->num_col_gpios = ncol = of_gpio_named_count(np, "col-gpios");
425	if (nrow <= 0 || ncol <= 0) {
426		dev_err(dev, "number of keypad rows/columns not specified\n");
427		return ERR_PTR(-EINVAL);
428	}
429
430	if (of_get_property(np, "linux,no-autorepeat", NULL))
431		pdata->no_autorepeat = true;
432
433	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
434			of_property_read_bool(np, "linux,wakeup"); /* legacy */
435
436	if (of_get_property(np, "gpio-activelow", NULL))
437		pdata->active_low = true;
438
439	pdata->drive_inactive_cols =
440		of_property_read_bool(np, "drive-inactive-cols");
441
442	of_property_read_u32(np, "debounce-delay-ms", &pdata->debounce_ms);
443	of_property_read_u32(np, "col-scan-delay-us",
444						&pdata->col_scan_delay_us);
445
446	gpios = devm_kzalloc(dev,
447			     sizeof(unsigned int) *
448				(pdata->num_row_gpios + pdata->num_col_gpios),
449			     GFP_KERNEL);
450	if (!gpios) {
451		dev_err(dev, "could not allocate memory for gpios\n");
452		return ERR_PTR(-ENOMEM);
453	}
454
455	for (i = 0; i < pdata->num_row_gpios; i++)
456		gpios[i] = of_get_named_gpio(np, "row-gpios", i);
 
 
 
 
457
458	for (i = 0; i < pdata->num_col_gpios; i++)
459		gpios[pdata->num_row_gpios + i] =
460			of_get_named_gpio(np, "col-gpios", i);
 
 
 
461
462	pdata->row_gpios = gpios;
463	pdata->col_gpios = &gpios[pdata->num_row_gpios];
464
465	return pdata;
466}
467#else
468static inline struct matrix_keypad_platform_data *
469matrix_keypad_parse_dt(struct device *dev)
470{
471	dev_err(dev, "no platform data defined\n");
472
473	return ERR_PTR(-EINVAL);
474}
475#endif
476
477static int matrix_keypad_probe(struct platform_device *pdev)
478{
479	const struct matrix_keypad_platform_data *pdata;
480	struct matrix_keypad *keypad;
481	struct input_dev *input_dev;
482	int err;
483
484	pdata = dev_get_platdata(&pdev->dev);
485	if (!pdata) {
486		pdata = matrix_keypad_parse_dt(&pdev->dev);
487		if (IS_ERR(pdata)) {
488			dev_err(&pdev->dev, "no platform data defined\n");
489			return PTR_ERR(pdata);
490		}
491	} else if (!pdata->keymap_data) {
492		dev_err(&pdev->dev, "no keymap data defined\n");
493		return -EINVAL;
494	}
495
496	keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
497	input_dev = input_allocate_device();
498	if (!keypad || !input_dev) {
499		err = -ENOMEM;
500		goto err_free_mem;
501	}
502
503	keypad->input_dev = input_dev;
504	keypad->pdata = pdata;
505	keypad->row_shift = get_count_order(pdata->num_col_gpios);
506	keypad->stopped = true;
507	INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
508	spin_lock_init(&keypad->lock);
509
510	input_dev->name		= pdev->name;
511	input_dev->id.bustype	= BUS_HOST;
512	input_dev->dev.parent	= &pdev->dev;
513	input_dev->open		= matrix_keypad_start;
514	input_dev->close	= matrix_keypad_stop;
515
516	err = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
517					 pdata->num_row_gpios,
518					 pdata->num_col_gpios,
519					 NULL, input_dev);
520	if (err) {
521		dev_err(&pdev->dev, "failed to build keymap\n");
522		goto err_free_mem;
523	}
524
525	if (!pdata->no_autorepeat)
526		__set_bit(EV_REP, input_dev->evbit);
527	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
528	input_set_drvdata(input_dev, keypad);
529
530	err = matrix_keypad_init_gpio(pdev, keypad);
531	if (err)
532		goto err_free_mem;
533
534	err = input_register_device(keypad->input_dev);
535	if (err)
536		goto err_free_gpio;
537
538	device_init_wakeup(&pdev->dev, pdata->wakeup);
539	platform_set_drvdata(pdev, keypad);
540
541	return 0;
542
543err_free_gpio:
544	matrix_keypad_free_gpio(keypad);
545err_free_mem:
546	input_free_device(input_dev);
547	kfree(keypad);
548	return err;
549}
550
551static int matrix_keypad_remove(struct platform_device *pdev)
552{
553	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
554
555	matrix_keypad_free_gpio(keypad);
556	input_unregister_device(keypad->input_dev);
557	kfree(keypad);
558
559	return 0;
560}
561
562#ifdef CONFIG_OF
563static const struct of_device_id matrix_keypad_dt_match[] = {
564	{ .compatible = "gpio-matrix-keypad" },
565	{ }
566};
567MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
568#endif
569
570static struct platform_driver matrix_keypad_driver = {
571	.probe		= matrix_keypad_probe,
572	.remove		= matrix_keypad_remove,
573	.driver		= {
574		.name	= "matrix-keypad",
575		.pm	= &matrix_keypad_pm_ops,
576		.of_match_table = of_match_ptr(matrix_keypad_dt_match),
577	},
578};
579module_platform_driver(matrix_keypad_driver);
580
581MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
582MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
583MODULE_LICENSE("GPL v2");
584MODULE_ALIAS("platform:matrix-keypad");