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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");
v3.1
 
  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/init.h>
 18#include <linux/input.h>
 19#include <linux/irq.h>
 20#include <linux/interrupt.h>
 21#include <linux/jiffies.h>
 22#include <linux/module.h>
 23#include <linux/gpio.h>
 24#include <linux/input/matrix_keypad.h>
 25#include <linux/slab.h>
 
 
 
 26
 27struct matrix_keypad {
 28	const struct matrix_keypad_platform_data *pdata;
 29	struct input_dev *input_dev;
 30	unsigned short *keycodes;
 31	unsigned int row_shift;
 32
 33	DECLARE_BITMAP(disabled_gpios, MATRIX_MAX_ROWS);
 34
 35	uint32_t last_key_state[MATRIX_MAX_COLS];
 36	struct delayed_work work;
 37	spinlock_t lock;
 38	bool scan_pending;
 39	bool stopped;
 40	bool gpio_all_disabled;
 41};
 42
 43/*
 44 * NOTE: normally the GPIO has to be put into HiZ when de-activated to cause
 45 * minmal side effect when scanning other columns, here it is configured to
 46 * be input, and it should work on most platforms.
 
 47 */
 48static void __activate_col(const struct matrix_keypad_platform_data *pdata,
 49			   int col, bool on)
 50{
 51	bool level_on = !pdata->active_low;
 52
 53	if (on) {
 54		gpio_direction_output(pdata->col_gpios[col], level_on);
 55	} else {
 56		gpio_set_value_cansleep(pdata->col_gpios[col], !level_on);
 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 struct matrix_keypad_platform_data *pdata = keypad->pdata;
121	uint32_t new_state[MATRIX_MAX_COLS];
122	int row, col, code;
123
124	/* de-activate all columns for scanning */
125	activate_all_cols(pdata, false);
126
127	memset(new_state, 0, sizeof(new_state));
128
 
 
 
129	/* assert each column and read the row status out */
130	for (col = 0; col < pdata->num_col_gpios; col++) {
131
132		activate_col(pdata, col, true);
133
134		for (row = 0; row < pdata->num_row_gpios; row++)
135			new_state[col] |=
136				row_asserted(pdata, row) ? (1 << row) : 0;
137
138		activate_col(pdata, col, false);
139	}
140
141	for (col = 0; col < pdata->num_col_gpios; col++) {
142		uint32_t bits_changed;
143
144		bits_changed = keypad->last_key_state[col] ^ new_state[col];
145		if (bits_changed == 0)
146			continue;
147
148		for (row = 0; row < pdata->num_row_gpios; row++) {
149			if ((bits_changed & (1 << row)) == 0)
150				continue;
151
152			code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
153			input_event(input_dev, EV_MSC, MSC_SCAN, code);
154			input_report_key(input_dev,
155					 keypad->keycodes[code],
156					 new_state[col] & (1 << row));
157		}
158	}
159	input_sync(input_dev);
160
161	memcpy(keypad->last_key_state, new_state, sizeof(new_state));
162
163	activate_all_cols(pdata, true);
164
165	/* Enable IRQs again */
166	spin_lock_irq(&keypad->lock);
167	keypad->scan_pending = false;
168	enable_row_irqs(keypad);
169	spin_unlock_irq(&keypad->lock);
170}
171
172static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
173{
174	struct matrix_keypad *keypad = id;
175	unsigned long flags;
176
177	spin_lock_irqsave(&keypad->lock, flags);
178
179	/*
180	 * See if another IRQ beaten us to it and scheduled the
181	 * scan already. In that case we should not try to
182	 * disable IRQs again.
183	 */
184	if (unlikely(keypad->scan_pending || keypad->stopped))
185		goto out;
186
187	disable_row_irqs(keypad);
188	keypad->scan_pending = true;
189	schedule_delayed_work(&keypad->work,
190		msecs_to_jiffies(keypad->pdata->debounce_ms));
191
192out:
193	spin_unlock_irqrestore(&keypad->lock, flags);
194	return IRQ_HANDLED;
195}
196
197static int matrix_keypad_start(struct input_dev *dev)
198{
199	struct matrix_keypad *keypad = input_get_drvdata(dev);
200
201	keypad->stopped = false;
202	mb();
203
204	/*
205	 * Schedule an immediate key scan to capture current key state;
206	 * columns will be activated and IRQs be enabled after the scan.
207	 */
208	schedule_delayed_work(&keypad->work, 0);
209
210	return 0;
211}
212
213static void matrix_keypad_stop(struct input_dev *dev)
214{
215	struct matrix_keypad *keypad = input_get_drvdata(dev);
216
 
217	keypad->stopped = true;
218	mb();
219	flush_work(&keypad->work.work);
 
220	/*
221	 * matrix_keypad_scan() will leave IRQs enabled;
222	 * we should disable them now.
223	 */
224	disable_row_irqs(keypad);
225}
226
227#ifdef CONFIG_PM
228static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
229{
230	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
231	unsigned int gpio;
232	int i;
233
234	if (pdata->clustered_irq > 0) {
235		if (enable_irq_wake(pdata->clustered_irq) == 0)
236			keypad->gpio_all_disabled = true;
237	} else {
238
239		for (i = 0; i < pdata->num_row_gpios; i++) {
240			if (!test_bit(i, keypad->disabled_gpios)) {
241				gpio = pdata->row_gpios[i];
242
243				if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
244					__set_bit(i, keypad->disabled_gpios);
245			}
246		}
247	}
248}
249
250static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
251{
252	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
253	unsigned int gpio;
254	int i;
255
256	if (pdata->clustered_irq > 0) {
257		if (keypad->gpio_all_disabled) {
258			disable_irq_wake(pdata->clustered_irq);
259			keypad->gpio_all_disabled = false;
260		}
261	} else {
262		for (i = 0; i < pdata->num_row_gpios; i++) {
263			if (test_and_clear_bit(i, keypad->disabled_gpios)) {
264				gpio = pdata->row_gpios[i];
265				disable_irq_wake(gpio_to_irq(gpio));
266			}
267		}
268	}
269}
270
271static int matrix_keypad_suspend(struct device *dev)
272{
273	struct platform_device *pdev = to_platform_device(dev);
274	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
275
276	matrix_keypad_stop(keypad->input_dev);
277
278	if (device_may_wakeup(&pdev->dev))
279		matrix_keypad_enable_wakeup(keypad);
280
281	return 0;
282}
283
284static int matrix_keypad_resume(struct device *dev)
285{
286	struct platform_device *pdev = to_platform_device(dev);
287	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
288
289	if (device_may_wakeup(&pdev->dev))
290		matrix_keypad_disable_wakeup(keypad);
291
292	matrix_keypad_start(keypad->input_dev);
293
294	return 0;
295}
296
297static const SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
298				matrix_keypad_suspend, matrix_keypad_resume);
299#endif
300
301static int __devinit init_matrix_gpio(struct platform_device *pdev,
302					struct matrix_keypad *keypad)
303{
304	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
305	int i, err = -EINVAL;
306
307	/* initialized strobe lines as outputs, activated */
308	for (i = 0; i < pdata->num_col_gpios; i++) {
309		err = gpio_request(pdata->col_gpios[i], "matrix_kbd_col");
310		if (err) {
311			dev_err(&pdev->dev,
312				"failed to request GPIO%d for COL%d\n",
313				pdata->col_gpios[i], i);
314			goto err_free_cols;
315		}
316
317		gpio_direction_output(pdata->col_gpios[i], !pdata->active_low);
318	}
319
320	for (i = 0; i < pdata->num_row_gpios; i++) {
321		err = gpio_request(pdata->row_gpios[i], "matrix_kbd_row");
322		if (err) {
323			dev_err(&pdev->dev,
324				"failed to request GPIO%d for ROW%d\n",
325				pdata->row_gpios[i], i);
326			goto err_free_rows;
327		}
328
329		gpio_direction_input(pdata->row_gpios[i]);
330	}
331
332	if (pdata->clustered_irq > 0) {
333		err = request_irq(pdata->clustered_irq,
334				matrix_keypad_interrupt,
335				pdata->clustered_irq_flags,
336				"matrix-keypad", keypad);
337		if (err) {
338			dev_err(&pdev->dev,
339				"Unable to acquire clustered interrupt\n");
340			goto err_free_rows;
341		}
342	} else {
343		for (i = 0; i < pdata->num_row_gpios; i++) {
344			err = request_irq(gpio_to_irq(pdata->row_gpios[i]),
 
345					matrix_keypad_interrupt,
346					IRQF_DISABLED |
347					IRQF_TRIGGER_RISING |
348					IRQF_TRIGGER_FALLING,
349					"matrix-keypad", keypad);
350			if (err) {
351				dev_err(&pdev->dev,
352					"Unable to acquire interrupt "
353					"for GPIO line %i\n",
354					pdata->row_gpios[i]);
355				goto err_free_irqs;
356			}
357		}
358	}
359
360	/* initialized as disabled - enabled by input->open */
361	disable_row_irqs(keypad);
362	return 0;
363
364err_free_irqs:
365	while (--i >= 0)
366		free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
367	i = pdata->num_row_gpios;
368err_free_rows:
369	while (--i >= 0)
370		gpio_free(pdata->row_gpios[i]);
371	i = pdata->num_col_gpios;
372err_free_cols:
373	while (--i >= 0)
374		gpio_free(pdata->col_gpios[i]);
375
376	return err;
377}
378
379static int __devinit matrix_keypad_probe(struct platform_device *pdev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
380{
381	const struct matrix_keypad_platform_data *pdata;
382	const struct matrix_keymap_data *keymap_data;
383	struct matrix_keypad *keypad;
384	struct input_dev *input_dev;
385	unsigned short *keycodes;
386	unsigned int row_shift;
387	int err;
388
389	pdata = pdev->dev.platform_data;
390	if (!pdata) {
391		dev_err(&pdev->dev, "no platform data defined\n");
392		return -EINVAL;
393	}
394
395	keymap_data = pdata->keymap_data;
396	if (!keymap_data) {
397		dev_err(&pdev->dev, "no keymap data defined\n");
398		return -EINVAL;
399	}
400
401	row_shift = get_count_order(pdata->num_col_gpios);
402
403	keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
404	keycodes = kzalloc((pdata->num_row_gpios << row_shift) *
405				sizeof(*keycodes),
406			   GFP_KERNEL);
407	input_dev = input_allocate_device();
408	if (!keypad || !keycodes || !input_dev) {
409		err = -ENOMEM;
410		goto err_free_mem;
411	}
412
413	keypad->input_dev = input_dev;
414	keypad->pdata = pdata;
415	keypad->keycodes = keycodes;
416	keypad->row_shift = row_shift;
417	keypad->stopped = true;
418	INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
419	spin_lock_init(&keypad->lock);
420
421	input_dev->name		= pdev->name;
422	input_dev->id.bustype	= BUS_HOST;
423	input_dev->dev.parent	= &pdev->dev;
424	input_dev->evbit[0]	= BIT_MASK(EV_KEY);
425	if (!pdata->no_autorepeat)
426		input_dev->evbit[0] |= BIT_MASK(EV_REP);
427	input_dev->open		= matrix_keypad_start;
428	input_dev->close	= matrix_keypad_stop;
429
430	input_dev->keycode	= keycodes;
431	input_dev->keycodesize	= sizeof(*keycodes);
432	input_dev->keycodemax	= pdata->num_row_gpios << row_shift;
433
434	matrix_keypad_build_keymap(keymap_data, row_shift,
435				   input_dev->keycode, input_dev->keybit);
 
 
436
 
 
437	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
438	input_set_drvdata(input_dev, keypad);
439
440	err = init_matrix_gpio(pdev, keypad);
441	if (err)
442		goto err_free_mem;
443
444	err = input_register_device(keypad->input_dev);
445	if (err)
446		goto err_free_mem;
447
448	device_init_wakeup(&pdev->dev, pdata->wakeup);
449	platform_set_drvdata(pdev, keypad);
450
451	return 0;
452
 
 
453err_free_mem:
454	input_free_device(input_dev);
455	kfree(keycodes);
456	kfree(keypad);
457	return err;
458}
459
460static int __devexit matrix_keypad_remove(struct platform_device *pdev)
461{
462	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
463	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
464	int i;
465
466	device_init_wakeup(&pdev->dev, 0);
467
468	if (pdata->clustered_irq > 0) {
469		free_irq(pdata->clustered_irq, keypad);
470	} else {
471		for (i = 0; i < pdata->num_row_gpios; i++)
472			free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
473	}
474
475	for (i = 0; i < pdata->num_row_gpios; i++)
476		gpio_free(pdata->row_gpios[i]);
477
478	for (i = 0; i < pdata->num_col_gpios; i++)
479		gpio_free(pdata->col_gpios[i]);
480
 
481	input_unregister_device(keypad->input_dev);
482	platform_set_drvdata(pdev, NULL);
483	kfree(keypad->keycodes);
484	kfree(keypad);
485
486	return 0;
487}
488
 
 
 
 
 
 
 
 
489static struct platform_driver matrix_keypad_driver = {
490	.probe		= matrix_keypad_probe,
491	.remove		= __devexit_p(matrix_keypad_remove),
492	.driver		= {
493		.name	= "matrix-keypad",
494		.owner	= THIS_MODULE,
495#ifdef CONFIG_PM
496		.pm	= &matrix_keypad_pm_ops,
497#endif
498	},
499};
500
501static int __init matrix_keypad_init(void)
502{
503	return platform_driver_register(&matrix_keypad_driver);
504}
505
506static void __exit matrix_keypad_exit(void)
507{
508	platform_driver_unregister(&matrix_keypad_driver);
509}
510
511module_init(matrix_keypad_init);
512module_exit(matrix_keypad_exit);
513
514MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
515MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
516MODULE_LICENSE("GPL v2");
517MODULE_ALIAS("platform:matrix-keypad");