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/clk.h>
11#include <linux/delay.h>
12#include <linux/err.h>
13#include <linux/input.h>
14#include <linux/interrupt.h>
15#include <linux/io.h>
16#include <linux/module.h>
17#include <linux/platform_device.h>
18#include <linux/pm.h>
19#include <linux/pm_runtime.h>
20#include <linux/slab.h>
21#include <linux/of.h>
22#include <linux/sched.h>
23#include <linux/input/samsung-keypad.h>
24
25#define SAMSUNG_KEYIFCON			0x00
26#define SAMSUNG_KEYIFSTSCLR			0x04
27#define SAMSUNG_KEYIFCOL			0x08
28#define SAMSUNG_KEYIFROW			0x0c
29#define SAMSUNG_KEYIFFC				0x10
30
31/* SAMSUNG_KEYIFCON */
32#define SAMSUNG_KEYIFCON_INT_F_EN		(1 << 0)
33#define SAMSUNG_KEYIFCON_INT_R_EN		(1 << 1)
34#define SAMSUNG_KEYIFCON_DF_EN			(1 << 2)
35#define SAMSUNG_KEYIFCON_FC_EN			(1 << 3)
36#define SAMSUNG_KEYIFCON_WAKEUPEN		(1 << 4)
37
38/* SAMSUNG_KEYIFSTSCLR */
39#define SAMSUNG_KEYIFSTSCLR_P_INT_MASK		(0xff << 0)
40#define SAMSUNG_KEYIFSTSCLR_R_INT_MASK		(0xff << 8)
41#define SAMSUNG_KEYIFSTSCLR_R_INT_OFFSET	8
42#define S5PV210_KEYIFSTSCLR_P_INT_MASK		(0x3fff << 0)
43#define S5PV210_KEYIFSTSCLR_R_INT_MASK		(0x3fff << 16)
44#define S5PV210_KEYIFSTSCLR_R_INT_OFFSET	16
45
46/* SAMSUNG_KEYIFCOL */
47#define SAMSUNG_KEYIFCOL_MASK			(0xff << 0)
48#define S5PV210_KEYIFCOLEN_MASK			(0xff << 8)
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
57enum samsung_keypad_type {
58	KEYPAD_TYPE_SAMSUNG,
59	KEYPAD_TYPE_S5PV210,
60};
61
62struct samsung_keypad {
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	enum samsung_keypad_type type;
72	unsigned int row_shift;
73	unsigned int rows;
74	unsigned int cols;
75	unsigned int row_state[SAMSUNG_MAX_COLS];
76	unsigned short keycodes[];
77};
78
79static void samsung_keypad_scan(struct samsung_keypad *keypad,
80				unsigned int *row_state)
81{
82	unsigned int col;
83	unsigned int val;
84
85	for (col = 0; col < keypad->cols; col++) {
86		if (keypad->type == KEYPAD_TYPE_S5PV210) {
87			val = S5PV210_KEYIFCOLEN_MASK;
88			val &= ~(1 << col) << 8;
89		} else {
90			val = SAMSUNG_KEYIFCOL_MASK;
91			val &= ~(1 << col);
92		}
93
94		writel(val, keypad->base + SAMSUNG_KEYIFCOL);
95		mdelay(1);
96
97		val = readl(keypad->base + SAMSUNG_KEYIFROW);
98		row_state[col] = ~val & ((1 << keypad->rows) - 1);
99	}
100
101	/* KEYIFCOL reg clear */
102	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
103}
104
105static bool samsung_keypad_report(struct samsung_keypad *keypad,
106				  unsigned int *row_state)
107{
108	struct input_dev *input_dev = keypad->input_dev;
109	unsigned int changed;
110	unsigned int pressed;
111	unsigned int key_down = 0;
112	unsigned int val;
113	unsigned int col, row;
114
115	for (col = 0; col < keypad->cols; col++) {
116		changed = row_state[col] ^ keypad->row_state[col];
117		key_down |= row_state[col];
118		if (!changed)
119			continue;
120
121		for (row = 0; row < keypad->rows; row++) {
122			if (!(changed & (1 << row)))
123				continue;
124
125			pressed = row_state[col] & (1 << row);
126
127			dev_dbg(&keypad->input_dev->dev,
128				"key %s, row: %d, col: %d\n",
129				pressed ? "pressed" : "released", row, col);
130
131			val = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
132
133			input_event(input_dev, EV_MSC, MSC_SCAN, val);
134			input_report_key(input_dev,
135					keypad->keycodes[val], pressed);
136		}
137		input_sync(keypad->input_dev);
138	}
139
140	memcpy(keypad->row_state, row_state, sizeof(keypad->row_state));
141
142	return key_down;
143}
144
145static irqreturn_t samsung_keypad_irq(int irq, void *dev_id)
146{
147	struct samsung_keypad *keypad = dev_id;
148	unsigned int row_state[SAMSUNG_MAX_COLS];
149	bool key_down;
150
151	pm_runtime_get_sync(&keypad->pdev->dev);
152
153	do {
154		readl(keypad->base + SAMSUNG_KEYIFSTSCLR);
155		/* Clear interrupt. */
156		writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
157
158		samsung_keypad_scan(keypad, row_state);
159
160		key_down = samsung_keypad_report(keypad, row_state);
161		if (key_down)
162			wait_event_timeout(keypad->wait, keypad->stopped,
163					   msecs_to_jiffies(50));
164
165	} while (key_down && !keypad->stopped);
166
167	pm_runtime_put(&keypad->pdev->dev);
168
169	return IRQ_HANDLED;
170}
171
172static void samsung_keypad_start(struct samsung_keypad *keypad)
173{
174	unsigned int val;
175
176	pm_runtime_get_sync(&keypad->pdev->dev);
177
178	/* Tell IRQ thread that it may poll the device. */
179	keypad->stopped = false;
180
181	clk_enable(keypad->clk);
182
183	/* Enable interrupt bits. */
184	val = readl(keypad->base + SAMSUNG_KEYIFCON);
185	val |= SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN;
186	writel(val, keypad->base + SAMSUNG_KEYIFCON);
187
188	/* KEYIFCOL reg clear. */
189	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
190
191	pm_runtime_put(&keypad->pdev->dev);
192}
193
194static void samsung_keypad_stop(struct samsung_keypad *keypad)
195{
196	unsigned int val;
197
198	pm_runtime_get_sync(&keypad->pdev->dev);
199
200	/* Signal IRQ thread to stop polling and disable the handler. */
201	keypad->stopped = true;
202	wake_up(&keypad->wait);
203	disable_irq(keypad->irq);
204
205	/* Clear interrupt. */
206	writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
207
208	/* Disable interrupt bits. */
209	val = readl(keypad->base + SAMSUNG_KEYIFCON);
210	val &= ~(SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN);
211	writel(val, keypad->base + SAMSUNG_KEYIFCON);
212
213	clk_disable(keypad->clk);
214
215	/*
216	 * Now that chip should not generate interrupts we can safely
217	 * re-enable the handler.
218	 */
219	enable_irq(keypad->irq);
220
221	pm_runtime_put(&keypad->pdev->dev);
222}
223
224static int samsung_keypad_open(struct input_dev *input_dev)
225{
226	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
227
228	samsung_keypad_start(keypad);
229
230	return 0;
231}
232
233static void samsung_keypad_close(struct input_dev *input_dev)
234{
235	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
236
237	samsung_keypad_stop(keypad);
238}
239
240#ifdef CONFIG_OF
241static struct samsung_keypad_platdata *
242samsung_keypad_parse_dt(struct device *dev)
243{
244	struct samsung_keypad_platdata *pdata;
245	struct matrix_keymap_data *keymap_data;
246	uint32_t *keymap, num_rows = 0, num_cols = 0;
247	struct device_node *np = dev->of_node, *key_np;
248	unsigned int key_count;
249
250	if (!np) {
251		dev_err(dev, "missing device tree data\n");
252		return ERR_PTR(-EINVAL);
253	}
254
255	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
256	if (!pdata) {
257		dev_err(dev, "could not allocate memory for platform data\n");
258		return ERR_PTR(-ENOMEM);
259	}
260
261	of_property_read_u32(np, "samsung,keypad-num-rows", &num_rows);
262	of_property_read_u32(np, "samsung,keypad-num-columns", &num_cols);
263	if (!num_rows || !num_cols) {
264		dev_err(dev, "number of keypad rows/columns not specified\n");
265		return ERR_PTR(-EINVAL);
266	}
267	pdata->rows = num_rows;
268	pdata->cols = num_cols;
269
270	keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
271	if (!keymap_data) {
272		dev_err(dev, "could not allocate memory for keymap data\n");
273		return ERR_PTR(-ENOMEM);
274	}
275	pdata->keymap_data = keymap_data;
276
277	key_count = of_get_child_count(np);
278	keymap_data->keymap_size = key_count;
279	keymap = devm_kcalloc(dev, key_count, sizeof(uint32_t), GFP_KERNEL);
280	if (!keymap) {
281		dev_err(dev, "could not allocate memory for keymap\n");
282		return ERR_PTR(-ENOMEM);
283	}
284	keymap_data->keymap = keymap;
285
286	for_each_child_of_node(np, key_np) {
287		u32 row, col, key_code;
288		of_property_read_u32(key_np, "keypad,row", &row);
289		of_property_read_u32(key_np, "keypad,column", &col);
290		of_property_read_u32(key_np, "linux,code", &key_code);
291		*keymap++ = KEY(row, col, key_code);
292	}
293
294	pdata->no_autorepeat = of_property_read_bool(np, "linux,input-no-autorepeat");
295
296	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
297			/* legacy name */
298			of_property_read_bool(np, "linux,input-wakeup");
299
300
301	return pdata;
302}
303#else
304static struct samsung_keypad_platdata *
305samsung_keypad_parse_dt(struct device *dev)
306{
307	dev_err(dev, "no platform data defined\n");
308
309	return ERR_PTR(-EINVAL);
310}
311#endif
312
313static int samsung_keypad_probe(struct platform_device *pdev)
314{
315	const struct samsung_keypad_platdata *pdata;
316	const struct matrix_keymap_data *keymap_data;
317	struct samsung_keypad *keypad;
318	struct resource *res;
319	struct input_dev *input_dev;
320	unsigned int row_shift;
321	unsigned int keymap_size;
322	int error;
323
324	pdata = dev_get_platdata(&pdev->dev);
325	if (!pdata) {
326		pdata = samsung_keypad_parse_dt(&pdev->dev);
327		if (IS_ERR(pdata))
328			return PTR_ERR(pdata);
329	}
330
331	keymap_data = pdata->keymap_data;
332	if (!keymap_data) {
333		dev_err(&pdev->dev, "no keymap data defined\n");
334		return -EINVAL;
335	}
336
337	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
338		return -EINVAL;
339
340	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
341		return -EINVAL;
342
343	/* initialize the gpio */
344	if (pdata->cfg_gpio)
345		pdata->cfg_gpio(pdata->rows, pdata->cols);
346
347	row_shift = get_count_order(pdata->cols);
348	keymap_size = (pdata->rows << row_shift) * sizeof(keypad->keycodes[0]);
349
350	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad) + keymap_size,
351			      GFP_KERNEL);
352	input_dev = devm_input_allocate_device(&pdev->dev);
353	if (!keypad || !input_dev)
354		return -ENOMEM;
355
356	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
357	if (!res)
358		return -ENODEV;
359
360	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
361	if (!keypad->base)
362		return -EBUSY;
363
364	keypad->clk = devm_clk_get(&pdev->dev, "keypad");
365	if (IS_ERR(keypad->clk)) {
366		dev_err(&pdev->dev, "failed to get keypad clk\n");
367		return PTR_ERR(keypad->clk);
368	}
369
370	error = clk_prepare(keypad->clk);
371	if (error) {
372		dev_err(&pdev->dev, "keypad clock prepare failed\n");
373		return error;
374	}
375
376	keypad->input_dev = input_dev;
377	keypad->pdev = pdev;
378	keypad->row_shift = row_shift;
379	keypad->rows = pdata->rows;
380	keypad->cols = pdata->cols;
381	keypad->stopped = true;
382	init_waitqueue_head(&keypad->wait);
383
384	if (pdev->dev.of_node)
385		keypad->type = of_device_is_compatible(pdev->dev.of_node,
386					"samsung,s5pv210-keypad");
387	else
388		keypad->type = platform_get_device_id(pdev)->driver_data;
389
390	input_dev->name = pdev->name;
391	input_dev->id.bustype = BUS_HOST;
392	input_dev->dev.parent = &pdev->dev;
393
394	input_dev->open = samsung_keypad_open;
395	input_dev->close = samsung_keypad_close;
396
397	error = matrix_keypad_build_keymap(keymap_data, NULL,
398					   pdata->rows, pdata->cols,
399					   keypad->keycodes, input_dev);
400	if (error) {
401		dev_err(&pdev->dev, "failed to build keymap\n");
402		goto err_unprepare_clk;
403	}
404
405	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
406	if (!pdata->no_autorepeat)
407		__set_bit(EV_REP, input_dev->evbit);
408
409	input_set_drvdata(input_dev, keypad);
410
411	keypad->irq = platform_get_irq(pdev, 0);
412	if (keypad->irq < 0) {
413		error = keypad->irq;
414		goto err_unprepare_clk;
415	}
416
417	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
418					  samsung_keypad_irq, IRQF_ONESHOT,
419					  dev_name(&pdev->dev), keypad);
420	if (error) {
421		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
422		goto err_unprepare_clk;
423	}
424
425	device_init_wakeup(&pdev->dev, pdata->wakeup);
426	platform_set_drvdata(pdev, keypad);
427	pm_runtime_enable(&pdev->dev);
428
429	error = input_register_device(keypad->input_dev);
430	if (error)
431		goto err_disable_runtime_pm;
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
440err_disable_runtime_pm:
441	pm_runtime_disable(&pdev->dev);
442err_unprepare_clk:
443	clk_unprepare(keypad->clk);
444	return error;
445}
446
447static void samsung_keypad_remove(struct platform_device *pdev)
448{
449	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
450
451	pm_runtime_disable(&pdev->dev);
452
453	input_unregister_device(keypad->input_dev);
454
455	clk_unprepare(keypad->clk);
456}
457
458static int samsung_keypad_runtime_suspend(struct device *dev)
459{
460	struct platform_device *pdev = to_platform_device(dev);
461	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
462	unsigned int val;
463	int error;
464
465	if (keypad->stopped)
466		return 0;
467
468	/* This may fail on some SoCs due to lack of controller support */
469	error = enable_irq_wake(keypad->irq);
470	if (!error)
471		keypad->wake_enabled = true;
472
473	val = readl(keypad->base + SAMSUNG_KEYIFCON);
474	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
475	writel(val, keypad->base + SAMSUNG_KEYIFCON);
476
477	clk_disable(keypad->clk);
478
479	return 0;
480}
481
482static int samsung_keypad_runtime_resume(struct device *dev)
483{
484	struct platform_device *pdev = to_platform_device(dev);
485	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
486	unsigned int val;
487
488	if (keypad->stopped)
489		return 0;
490
491	clk_enable(keypad->clk);
492
493	val = readl(keypad->base + SAMSUNG_KEYIFCON);
494	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
495	writel(val, keypad->base + SAMSUNG_KEYIFCON);
496
497	if (keypad->wake_enabled)
498		disable_irq_wake(keypad->irq);
499
500	return 0;
501}
502
503static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
504					 bool enable)
505{
506	unsigned int val;
507
508	clk_enable(keypad->clk);
509
510	val = readl(keypad->base + SAMSUNG_KEYIFCON);
511	if (enable) {
512		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
513		if (device_may_wakeup(&keypad->pdev->dev))
514			enable_irq_wake(keypad->irq);
515	} else {
516		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
517		if (device_may_wakeup(&keypad->pdev->dev))
518			disable_irq_wake(keypad->irq);
519	}
520	writel(val, keypad->base + SAMSUNG_KEYIFCON);
521
522	clk_disable(keypad->clk);
523}
524
525static int samsung_keypad_suspend(struct device *dev)
526{
527	struct platform_device *pdev = to_platform_device(dev);
528	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
529	struct input_dev *input_dev = keypad->input_dev;
530
531	mutex_lock(&input_dev->mutex);
532
533	if (input_device_enabled(input_dev))
534		samsung_keypad_stop(keypad);
535
536	samsung_keypad_toggle_wakeup(keypad, true);
537
538	mutex_unlock(&input_dev->mutex);
539
540	return 0;
541}
542
543static int samsung_keypad_resume(struct device *dev)
544{
545	struct platform_device *pdev = to_platform_device(dev);
546	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
547	struct input_dev *input_dev = keypad->input_dev;
548
549	mutex_lock(&input_dev->mutex);
550
551	samsung_keypad_toggle_wakeup(keypad, false);
552
553	if (input_device_enabled(input_dev))
554		samsung_keypad_start(keypad);
555
556	mutex_unlock(&input_dev->mutex);
557
558	return 0;
559}
560
561static const struct dev_pm_ops samsung_keypad_pm_ops = {
562	SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
563	RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
564		       samsung_keypad_runtime_resume, NULL)
565};
566
567#ifdef CONFIG_OF
568static const struct of_device_id samsung_keypad_dt_match[] = {
569	{ .compatible = "samsung,s3c6410-keypad" },
570	{ .compatible = "samsung,s5pv210-keypad" },
571	{},
572};
573MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
574#endif
575
576static const struct platform_device_id samsung_keypad_driver_ids[] = {
577	{
578		.name		= "samsung-keypad",
579		.driver_data	= KEYPAD_TYPE_SAMSUNG,
580	}, {
581		.name		= "s5pv210-keypad",
582		.driver_data	= KEYPAD_TYPE_S5PV210,
583	},
584	{ },
585};
586MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
587
588static struct platform_driver samsung_keypad_driver = {
589	.probe		= samsung_keypad_probe,
590	.remove_new	= samsung_keypad_remove,
591	.driver		= {
592		.name	= "samsung-keypad",
593		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
594		.pm	= pm_ptr(&samsung_keypad_pm_ops),
595	},
596	.id_table	= samsung_keypad_driver_ids,
597};
598module_platform_driver(samsung_keypad_driver);
599
600MODULE_DESCRIPTION("Samsung keypad driver");
601MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
602MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
603MODULE_LICENSE("GPL");
604