samsung-keypad.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Samsung keypad driver
  4 *
  5 * Copyright (C) 2010 Samsung Electronics Co.Ltd
  6 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
  7 * Author: Donghwa Lee <dh09.lee@samsung.com>
  8 */
  9
 10#include <linux/bits.h>
 11#include <linux/clk.h>
 12#include <linux/delay.h>
 13#include <linux/err.h>
 14#include <linux/input.h>
 15#include <linux/interrupt.h>
 16#include <linux/io.h>
 17#include <linux/module.h>
 18#include <linux/platform_device.h>
 19#include <linux/pm.h>
 20#include <linux/pm_runtime.h>
 21#include <linux/slab.h>
 22#include <linux/of.h>
 23#include <linux/sched.h>
 24#include <linux/input/samsung-keypad.h>
 25
 26#define SAMSUNG_KEYIFCON			0x00
 27#define SAMSUNG_KEYIFSTSCLR			0x04
 28#define SAMSUNG_KEYIFCOL			0x08
 29#define SAMSUNG_KEYIFROW			0x0c
 30#define SAMSUNG_KEYIFFC				0x10
 31
 32/* SAMSUNG_KEYIFCON */
 33#define SAMSUNG_KEYIFCON_INT_F_EN		BIT(0)
 34#define SAMSUNG_KEYIFCON_INT_R_EN		BIT(1)
 35#define SAMSUNG_KEYIFCON_DF_EN			BIT(2)
 36#define SAMSUNG_KEYIFCON_FC_EN			BIT(3)
 37#define SAMSUNG_KEYIFCON_WAKEUPEN		BIT(4)
 38
 39/* SAMSUNG_KEYIFSTSCLR */
 40#define SAMSUNG_KEYIFSTSCLR_P_INT_MASK		(0xff << 0)
 41#define SAMSUNG_KEYIFSTSCLR_R_INT_MASK		(0xff << 8)
 42#define SAMSUNG_KEYIFSTSCLR_R_INT_OFFSET	8
 43#define S5PV210_KEYIFSTSCLR_P_INT_MASK		(0x3fff << 0)
 44#define S5PV210_KEYIFSTSCLR_R_INT_MASK		(0x3fff << 16)
 45#define S5PV210_KEYIFSTSCLR_R_INT_OFFSET	16
 46
 47/* SAMSUNG_KEYIFCOL */
 48#define SAMSUNG_KEYIFCOL_MASK			0xff
 49
 50/* SAMSUNG_KEYIFROW */
 51#define SAMSUNG_KEYIFROW_MASK			(0xff << 0)
 52#define S5PV210_KEYIFROW_MASK			(0x3fff << 0)
 53
 54/* SAMSUNG_KEYIFFC */
 55#define SAMSUNG_KEYIFFC_MASK			(0x3ff << 0)
 56
 57struct samsung_chip_info {
 58	unsigned int column_shift;
 59};
 60
 61struct samsung_keypad {
 62	const struct samsung_chip_info *chip;
 63	struct input_dev *input_dev;
 64	struct platform_device *pdev;
 65	struct clk *clk;
 66	void __iomem *base;
 67	wait_queue_head_t wait;
 68	bool stopped;
 69	bool wake_enabled;
 70	int irq;
 71	unsigned int row_shift;
 72	unsigned int rows;
 73	unsigned int cols;
 74	unsigned int row_state[SAMSUNG_MAX_COLS];
 75	unsigned short keycodes[];
 76};
 77
 78static void samsung_keypad_scan(struct samsung_keypad *keypad,
 79				unsigned int *row_state)
 80{
 81	unsigned int col;
 82	unsigned int val;
 83
 84	for (col = 0; col < keypad->cols; col++) {
 85		val = SAMSUNG_KEYIFCOL_MASK & ~BIT(col);
 86		val <<= keypad->chip->column_shift;
 87
 88		writel(val, keypad->base + SAMSUNG_KEYIFCOL);
 89		mdelay(1);
 90
 91		val = readl(keypad->base + SAMSUNG_KEYIFROW);
 92		row_state[col] = ~val & GENMASK(keypad->rows - 1, 0);
 93	}
 94
 95	/* KEYIFCOL reg clear */
 96	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
 97}
 98
 99static bool samsung_keypad_report(struct samsung_keypad *keypad,
100				  unsigned int *row_state)
101{
102	struct input_dev *input_dev = keypad->input_dev;
103	unsigned int changed;
104	unsigned int pressed;
105	unsigned int key_down = 0;
106	unsigned int val;
107	unsigned int col, row;
108
109	for (col = 0; col < keypad->cols; col++) {
110		changed = row_state[col] ^ keypad->row_state[col];
111		key_down |= row_state[col];
112		if (!changed)
113			continue;
114
115		for (row = 0; row < keypad->rows; row++) {
116			if (!(changed & BIT(row)))
117				continue;
118
119			pressed = row_state[col] & BIT(row);
120
121			dev_dbg(&keypad->input_dev->dev,
122				"key %s, row: %d, col: %d\n",
123				pressed ? "pressed" : "released", row, col);
124
125			val = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
126
127			input_event(input_dev, EV_MSC, MSC_SCAN, val);
128			input_report_key(input_dev,
129					keypad->keycodes[val], pressed);
130		}
131		input_sync(keypad->input_dev);
132	}
133
134	memcpy(keypad->row_state, row_state, sizeof(keypad->row_state));
135
136	return key_down;
137}
138
139static irqreturn_t samsung_keypad_irq(int irq, void *dev_id)
140{
141	struct samsung_keypad *keypad = dev_id;
142	unsigned int row_state[SAMSUNG_MAX_COLS];
143	bool key_down;
144
145	pm_runtime_get_sync(&keypad->pdev->dev);
146
147	do {
148		readl(keypad->base + SAMSUNG_KEYIFSTSCLR);
149		/* Clear interrupt. */
150		writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
151
152		samsung_keypad_scan(keypad, row_state);
153
154		key_down = samsung_keypad_report(keypad, row_state);
155		if (key_down)
156			wait_event_timeout(keypad->wait, keypad->stopped,
157					   msecs_to_jiffies(50));
158
159	} while (key_down && !keypad->stopped);
160
161	pm_runtime_put(&keypad->pdev->dev);
162
163	return IRQ_HANDLED;
164}
165
166static void samsung_keypad_start(struct samsung_keypad *keypad)
167{
168	unsigned int val;
169
170	pm_runtime_get_sync(&keypad->pdev->dev);
171
172	/* Tell IRQ thread that it may poll the device. */
173	keypad->stopped = false;
174
175	clk_enable(keypad->clk);
176
177	/* Enable interrupt bits. */
178	val = readl(keypad->base + SAMSUNG_KEYIFCON);
179	val |= SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN;
180	writel(val, keypad->base + SAMSUNG_KEYIFCON);
181
182	/* KEYIFCOL reg clear. */
183	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
184
185	pm_runtime_put(&keypad->pdev->dev);
186}
187
188static void samsung_keypad_stop(struct samsung_keypad *keypad)
189{
190	unsigned int val;
191
192	pm_runtime_get_sync(&keypad->pdev->dev);
193
194	/* Signal IRQ thread to stop polling and disable the handler. */
195	keypad->stopped = true;
196	wake_up(&keypad->wait);
197	disable_irq(keypad->irq);
198
199	/* Clear interrupt. */
200	writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
201
202	/* Disable interrupt bits. */
203	val = readl(keypad->base + SAMSUNG_KEYIFCON);
204	val &= ~(SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN);
205	writel(val, keypad->base + SAMSUNG_KEYIFCON);
206
207	clk_disable(keypad->clk);
208
209	/*
210	 * Now that chip should not generate interrupts we can safely
211	 * re-enable the handler.
212	 */
213	enable_irq(keypad->irq);
214
215	pm_runtime_put(&keypad->pdev->dev);
216}
217
218static int samsung_keypad_open(struct input_dev *input_dev)
219{
220	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
221
222	samsung_keypad_start(keypad);
223
224	return 0;
225}
226
227static void samsung_keypad_close(struct input_dev *input_dev)
228{
229	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
230
231	samsung_keypad_stop(keypad);
232}
233
234#ifdef CONFIG_OF
235static struct samsung_keypad_platdata *
236samsung_keypad_parse_dt(struct device *dev)
237{
238	struct samsung_keypad_platdata *pdata;
239	struct matrix_keymap_data *keymap_data;
240	uint32_t *keymap, num_rows = 0, num_cols = 0;
241	struct device_node *np = dev->of_node, *key_np;
242	unsigned int key_count;
243
244	if (!np) {
245		dev_err(dev, "missing device tree data\n");
246		return ERR_PTR(-EINVAL);
247	}
248
249	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
250	if (!pdata) {
251		dev_err(dev, "could not allocate memory for platform data\n");
252		return ERR_PTR(-ENOMEM);
253	}
254
255	of_property_read_u32(np, "samsung,keypad-num-rows", &num_rows);
256	of_property_read_u32(np, "samsung,keypad-num-columns", &num_cols);
257	if (!num_rows || !num_cols) {
258		dev_err(dev, "number of keypad rows/columns not specified\n");
259		return ERR_PTR(-EINVAL);
260	}
261	pdata->rows = num_rows;
262	pdata->cols = num_cols;
263
264	keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
265	if (!keymap_data) {
266		dev_err(dev, "could not allocate memory for keymap data\n");
267		return ERR_PTR(-ENOMEM);
268	}
269	pdata->keymap_data = keymap_data;
270
271	key_count = of_get_child_count(np);
272	keymap_data->keymap_size = key_count;
273	keymap = devm_kcalloc(dev, key_count, sizeof(uint32_t), GFP_KERNEL);
274	if (!keymap) {
275		dev_err(dev, "could not allocate memory for keymap\n");
276		return ERR_PTR(-ENOMEM);
277	}
278	keymap_data->keymap = keymap;
279
280	for_each_child_of_node(np, key_np) {
281		u32 row, col, key_code;
282		of_property_read_u32(key_np, "keypad,row", &row);
283		of_property_read_u32(key_np, "keypad,column", &col);
284		of_property_read_u32(key_np, "linux,code", &key_code);
285		*keymap++ = KEY(row, col, key_code);
286	}
287
288	pdata->no_autorepeat = of_property_read_bool(np, "linux,input-no-autorepeat");
289
290	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
291			/* legacy name */
292			of_property_read_bool(np, "linux,input-wakeup");
293
294
295	return pdata;
296}
297#else
298static struct samsung_keypad_platdata *
299samsung_keypad_parse_dt(struct device *dev)
300{
301	dev_err(dev, "no platform data defined\n");
302
303	return ERR_PTR(-EINVAL);
304}
305#endif
306
307static int samsung_keypad_probe(struct platform_device *pdev)
308{
309	const struct samsung_keypad_platdata *pdata;
310	const struct matrix_keymap_data *keymap_data;
311	const struct platform_device_id *id;
312	struct samsung_keypad *keypad;
313	struct resource *res;
314	struct input_dev *input_dev;
315	unsigned int row_shift;
316	int error;
317
318	pdata = dev_get_platdata(&pdev->dev);
319	if (!pdata) {
320		pdata = samsung_keypad_parse_dt(&pdev->dev);
321		if (IS_ERR(pdata))
322			return PTR_ERR(pdata);
323	}
324
325	keymap_data = pdata->keymap_data;
326	if (!keymap_data) {
327		dev_err(&pdev->dev, "no keymap data defined\n");
328		return -EINVAL;
329	}
330
331	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
332		return -EINVAL;
333
334	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
335		return -EINVAL;
336
337	/* initialize the gpio */
338	if (pdata->cfg_gpio)
339		pdata->cfg_gpio(pdata->rows, pdata->cols);
340
341	row_shift = get_count_order(pdata->cols);
342
343	keypad = devm_kzalloc(&pdev->dev,
344			      struct_size(keypad, keycodes,
345					  pdata->rows << row_shift),
346			      GFP_KERNEL);
347	if (!keypad)
348		return -ENOMEM;
349
350	input_dev = devm_input_allocate_device(&pdev->dev);
351	if (!input_dev)
352		return -ENOMEM;
353
354	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
355	if (!res)
356		return -ENODEV;
357
358	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
359	if (!keypad->base)
360		return -EBUSY;
361
362	keypad->clk = devm_clk_get_prepared(&pdev->dev, "keypad");
363	if (IS_ERR(keypad->clk)) {
364		dev_err(&pdev->dev, "failed to get keypad clk\n");
365		return PTR_ERR(keypad->clk);
366	}
367
368	keypad->input_dev = input_dev;
369	keypad->pdev = pdev;
370	keypad->row_shift = row_shift;
371	keypad->rows = pdata->rows;
372	keypad->cols = pdata->cols;
373	keypad->stopped = true;
374	init_waitqueue_head(&keypad->wait);
375
376	keypad->chip = device_get_match_data(&pdev->dev);
377	if (!keypad->chip) {
378		id = platform_get_device_id(pdev);
379		if (id)
380			keypad->chip = (const void *)id->driver_data;
381	}
382
383	if (!keypad->chip) {
384		dev_err(&pdev->dev, "Unable to determine chip type");
385		return -EINVAL;
386	}
387
388	input_dev->name = pdev->name;
389	input_dev->id.bustype = BUS_HOST;
390
391	input_dev->open = samsung_keypad_open;
392	input_dev->close = samsung_keypad_close;
393
394	error = matrix_keypad_build_keymap(keymap_data, NULL,
395					   pdata->rows, pdata->cols,
396					   keypad->keycodes, input_dev);
397	if (error) {
398		dev_err(&pdev->dev, "failed to build keymap\n");
399		return error;
400	}
401
402	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
403	if (!pdata->no_autorepeat)
404		__set_bit(EV_REP, input_dev->evbit);
405
406	input_set_drvdata(input_dev, keypad);
407
408	keypad->irq = platform_get_irq(pdev, 0);
409	if (keypad->irq < 0) {
410		error = keypad->irq;
411		return error;
412	}
413
414	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
415					  samsung_keypad_irq, IRQF_ONESHOT,
416					  dev_name(&pdev->dev), keypad);
417	if (error) {
418		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
419		return error;
420	}
421
422	device_init_wakeup(&pdev->dev, pdata->wakeup);
423	platform_set_drvdata(pdev, keypad);
424
425	error = devm_pm_runtime_enable(&pdev->dev);
426	if (error)
427		return error;
428
429	error = input_register_device(keypad->input_dev);
430	if (error)
431		return error;
432
433	if (pdev->dev.of_node) {
434		devm_kfree(&pdev->dev, (void *)pdata->keymap_data->keymap);
435		devm_kfree(&pdev->dev, (void *)pdata->keymap_data);
436		devm_kfree(&pdev->dev, (void *)pdata);
437	}
438	return 0;
439}
440
441static int samsung_keypad_runtime_suspend(struct device *dev)
442{
443	struct platform_device *pdev = to_platform_device(dev);
444	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
445	unsigned int val;
446	int error;
447
448	if (keypad->stopped)
449		return 0;
450
451	/* This may fail on some SoCs due to lack of controller support */
452	error = enable_irq_wake(keypad->irq);
453	if (!error)
454		keypad->wake_enabled = true;
455
456	val = readl(keypad->base + SAMSUNG_KEYIFCON);
457	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
458	writel(val, keypad->base + SAMSUNG_KEYIFCON);
459
460	clk_disable(keypad->clk);
461
462	return 0;
463}
464
465static int samsung_keypad_runtime_resume(struct device *dev)
466{
467	struct platform_device *pdev = to_platform_device(dev);
468	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
469	unsigned int val;
470
471	if (keypad->stopped)
472		return 0;
473
474	clk_enable(keypad->clk);
475
476	val = readl(keypad->base + SAMSUNG_KEYIFCON);
477	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
478	writel(val, keypad->base + SAMSUNG_KEYIFCON);
479
480	if (keypad->wake_enabled)
481		disable_irq_wake(keypad->irq);
482
483	return 0;
484}
485
486static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
487					 bool enable)
488{
489	unsigned int val;
490
491	clk_enable(keypad->clk);
492
493	val = readl(keypad->base + SAMSUNG_KEYIFCON);
494	if (enable) {
495		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
496		if (device_may_wakeup(&keypad->pdev->dev))
497			enable_irq_wake(keypad->irq);
498	} else {
499		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
500		if (device_may_wakeup(&keypad->pdev->dev))
501			disable_irq_wake(keypad->irq);
502	}
503	writel(val, keypad->base + SAMSUNG_KEYIFCON);
504
505	clk_disable(keypad->clk);
506}
507
508static int samsung_keypad_suspend(struct device *dev)
509{
510	struct platform_device *pdev = to_platform_device(dev);
511	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
512	struct input_dev *input_dev = keypad->input_dev;
513
514	guard(mutex)(&input_dev->mutex);
515
516	if (input_device_enabled(input_dev))
517		samsung_keypad_stop(keypad);
518
519	samsung_keypad_toggle_wakeup(keypad, true);
520
521	return 0;
522}
523
524static int samsung_keypad_resume(struct device *dev)
525{
526	struct platform_device *pdev = to_platform_device(dev);
527	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
528	struct input_dev *input_dev = keypad->input_dev;
529
530	guard(mutex)(&input_dev->mutex);
531
532	samsung_keypad_toggle_wakeup(keypad, false);
533
534	if (input_device_enabled(input_dev))
535		samsung_keypad_start(keypad);
536
537	return 0;
538}
539
540static const struct dev_pm_ops samsung_keypad_pm_ops = {
541	SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
542	RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
543		       samsung_keypad_runtime_resume, NULL)
544};
545
546static const struct samsung_chip_info samsung_s3c6410_chip_info = {
547	.column_shift = 0,
548};
549
550static const struct samsung_chip_info samsung_s5pv210_chip_info = {
551	.column_shift = 8,
552};
553
554#ifdef CONFIG_OF
555static const struct of_device_id samsung_keypad_dt_match[] = {
556	{
557		.compatible = "samsung,s3c6410-keypad",
558		.data = &samsung_s3c6410_chip_info,
559	}, {
560		.compatible = "samsung,s5pv210-keypad",
561		.data = &samsung_s5pv210_chip_info,
562	},
563	{ }
564};
565MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
566#endif
567
568static const struct platform_device_id samsung_keypad_driver_ids[] = {
569	{
570		.name		= "samsung-keypad",
571		.driver_data	= (kernel_ulong_t)&samsung_s3c6410_chip_info,
572	}, {
573		.name		= "s5pv210-keypad",
574		.driver_data	= (kernel_ulong_t)&samsung_s5pv210_chip_info,
575	},
576	{ }
577};
578MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
579
580static struct platform_driver samsung_keypad_driver = {
581	.probe		= samsung_keypad_probe,
582	.driver		= {
583		.name	= "samsung-keypad",
584		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
585		.pm	= pm_ptr(&samsung_keypad_pm_ops),
586	},
587	.id_table	= samsung_keypad_driver_ids,
588};
589module_platform_driver(samsung_keypad_driver);
590
591MODULE_DESCRIPTION("Samsung keypad driver");
592MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
593MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
594MODULE_LICENSE("GPL");