1/*
2 * Samsung keypad driver
3 *
4 * Copyright (C) 2010 Samsung Electronics Co.Ltd
5 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
6 * Author: Donghwa Lee <dh09.lee@samsung.com>
7 *
8 * This program is free software; you can redistribute  it and/or modify it
9 * under  the terms of  the GNU General  Public License as published by the
10 * Free Software Foundation;  either version 2 of the  License, or (at your
11 * option) any later version.
12 */
13
14#include <linux/clk.h>
15#include <linux/delay.h>
16#include <linux/err.h>
17#include <linux/input.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/module.h>
21#include <linux/platform_device.h>
22#include <linux/pm.h>
23#include <linux/pm_runtime.h>
24#include <linux/slab.h>
25#include <linux/of.h>
26#include <linux/sched.h>
27#include <linux/input/samsung-keypad.h>
28
29#define SAMSUNG_KEYIFCON			0x00
30#define SAMSUNG_KEYIFSTSCLR			0x04
31#define SAMSUNG_KEYIFCOL			0x08
32#define SAMSUNG_KEYIFROW			0x0c
33#define SAMSUNG_KEYIFFC				0x10
34
35/* SAMSUNG_KEYIFCON */
36#define SAMSUNG_KEYIFCON_INT_F_EN		(1 << 0)
37#define SAMSUNG_KEYIFCON_INT_R_EN		(1 << 1)
38#define SAMSUNG_KEYIFCON_DF_EN			(1 << 2)
39#define SAMSUNG_KEYIFCON_FC_EN			(1 << 3)
40#define SAMSUNG_KEYIFCON_WAKEUPEN		(1 << 4)
41
42/* SAMSUNG_KEYIFSTSCLR */
43#define SAMSUNG_KEYIFSTSCLR_P_INT_MASK		(0xff << 0)
44#define SAMSUNG_KEYIFSTSCLR_R_INT_MASK		(0xff << 8)
45#define SAMSUNG_KEYIFSTSCLR_R_INT_OFFSET	8
46#define S5PV210_KEYIFSTSCLR_P_INT_MASK		(0x3fff << 0)
47#define S5PV210_KEYIFSTSCLR_R_INT_MASK		(0x3fff << 16)
48#define S5PV210_KEYIFSTSCLR_R_INT_OFFSET	16
49
50/* SAMSUNG_KEYIFCOL */
51#define SAMSUNG_KEYIFCOL_MASK			(0xff << 0)
52#define S5PV210_KEYIFCOLEN_MASK			(0xff << 8)
53
54/* SAMSUNG_KEYIFROW */
55#define SAMSUNG_KEYIFROW_MASK			(0xff << 0)
56#define S5PV210_KEYIFROW_MASK			(0x3fff << 0)
57
58/* SAMSUNG_KEYIFFC */
59#define SAMSUNG_KEYIFFC_MASK			(0x3ff << 0)
60
61enum samsung_keypad_type {
62	KEYPAD_TYPE_SAMSUNG,
63	KEYPAD_TYPE_S5PV210,
64};
65
66struct samsung_keypad {
67	struct input_dev *input_dev;
68	struct platform_device *pdev;
69	struct clk *clk;
70	void __iomem *base;
71	wait_queue_head_t wait;
72	bool stopped;
73	bool wake_enabled;
74	int irq;
75	enum samsung_keypad_type type;
76	unsigned int row_shift;
77	unsigned int rows;
78	unsigned int cols;
79	unsigned int row_state[SAMSUNG_MAX_COLS];
80	unsigned short keycodes[];
81};
82
83static void samsung_keypad_scan(struct samsung_keypad *keypad,
84				unsigned int *row_state)
85{
86	unsigned int col;
87	unsigned int val;
88
89	for (col = 0; col < keypad->cols; col++) {
90		if (keypad->type == KEYPAD_TYPE_S5PV210) {
91			val = S5PV210_KEYIFCOLEN_MASK;
92			val &= ~(1 << col) << 8;
93		} else {
94			val = SAMSUNG_KEYIFCOL_MASK;
95			val &= ~(1 << col);
96		}
97
98		writel(val, keypad->base + SAMSUNG_KEYIFCOL);
99		mdelay(1);
100
101		val = readl(keypad->base + SAMSUNG_KEYIFROW);
102		row_state[col] = ~val & ((1 << keypad->rows) - 1);
103	}
104
105	/* KEYIFCOL reg clear */
106	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
107}
108
109static bool samsung_keypad_report(struct samsung_keypad *keypad,
110				  unsigned int *row_state)
111{
112	struct input_dev *input_dev = keypad->input_dev;
113	unsigned int changed;
114	unsigned int pressed;
115	unsigned int key_down = 0;
116	unsigned int val;
117	unsigned int col, row;
118
119	for (col = 0; col < keypad->cols; col++) {
120		changed = row_state[col] ^ keypad->row_state[col];
121		key_down |= row_state[col];
122		if (!changed)
123			continue;
124
125		for (row = 0; row < keypad->rows; row++) {
126			if (!(changed & (1 << row)))
127				continue;
128
129			pressed = row_state[col] & (1 << row);
130
131			dev_dbg(&keypad->input_dev->dev,
132				"key %s, row: %d, col: %d\n",
133				pressed ? "pressed" : "released", row, col);
134
135			val = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
136
137			input_event(input_dev, EV_MSC, MSC_SCAN, val);
138			input_report_key(input_dev,
139					keypad->keycodes[val], pressed);
140		}
141		input_sync(keypad->input_dev);
142	}
143
144	memcpy(keypad->row_state, row_state, sizeof(keypad->row_state));
145
146	return key_down;
147}
148
149static irqreturn_t samsung_keypad_irq(int irq, void *dev_id)
150{
151	struct samsung_keypad *keypad = dev_id;
152	unsigned int row_state[SAMSUNG_MAX_COLS];
153	unsigned int val;
154	bool key_down;
155
156	pm_runtime_get_sync(&keypad->pdev->dev);
157
158	do {
159		val = readl(keypad->base + SAMSUNG_KEYIFSTSCLR);
160		/* Clear interrupt. */
161		writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
162
163		samsung_keypad_scan(keypad, row_state);
164
165		key_down = samsung_keypad_report(keypad, row_state);
166		if (key_down)
167			wait_event_timeout(keypad->wait, keypad->stopped,
168					   msecs_to_jiffies(50));
169
170	} while (key_down && !keypad->stopped);
171
172	pm_runtime_put(&keypad->pdev->dev);
173
174	return IRQ_HANDLED;
175}
176
177static void samsung_keypad_start(struct samsung_keypad *keypad)
178{
179	unsigned int val;
180
181	pm_runtime_get_sync(&keypad->pdev->dev);
182
183	/* Tell IRQ thread that it may poll the device. */
184	keypad->stopped = false;
185
186	clk_enable(keypad->clk);
187
188	/* Enable interrupt bits. */
189	val = readl(keypad->base + SAMSUNG_KEYIFCON);
190	val |= SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN;
191	writel(val, keypad->base + SAMSUNG_KEYIFCON);
192
193	/* KEYIFCOL reg clear. */
194	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
195
196	pm_runtime_put(&keypad->pdev->dev);
197}
198
199static void samsung_keypad_stop(struct samsung_keypad *keypad)
200{
201	unsigned int val;
202
203	pm_runtime_get_sync(&keypad->pdev->dev);
204
205	/* Signal IRQ thread to stop polling and disable the handler. */
206	keypad->stopped = true;
207	wake_up(&keypad->wait);
208	disable_irq(keypad->irq);
209
210	/* Clear interrupt. */
211	writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
212
213	/* Disable interrupt bits. */
214	val = readl(keypad->base + SAMSUNG_KEYIFCON);
215	val &= ~(SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN);
216	writel(val, keypad->base + SAMSUNG_KEYIFCON);
217
218	clk_disable(keypad->clk);
219
220	/*
221	 * Now that chip should not generate interrupts we can safely
222	 * re-enable the handler.
223	 */
224	enable_irq(keypad->irq);
225
226	pm_runtime_put(&keypad->pdev->dev);
227}
228
229static int samsung_keypad_open(struct input_dev *input_dev)
230{
231	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
232
233	samsung_keypad_start(keypad);
234
235	return 0;
236}
237
238static void samsung_keypad_close(struct input_dev *input_dev)
239{
240	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
241
242	samsung_keypad_stop(keypad);
243}
244
245#ifdef CONFIG_OF
246static struct samsung_keypad_platdata *
247samsung_keypad_parse_dt(struct device *dev)
248{
249	struct samsung_keypad_platdata *pdata;
250	struct matrix_keymap_data *keymap_data;
251	uint32_t *keymap, num_rows = 0, num_cols = 0;
252	struct device_node *np = dev->of_node, *key_np;
253	unsigned int key_count;
254
255	if (!np) {
256		dev_err(dev, "missing device tree data\n");
257		return ERR_PTR(-EINVAL);
258	}
259
260	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
261	if (!pdata) {
262		dev_err(dev, "could not allocate memory for platform data\n");
263		return ERR_PTR(-ENOMEM);
264	}
265
266	of_property_read_u32(np, "samsung,keypad-num-rows", &num_rows);
267	of_property_read_u32(np, "samsung,keypad-num-columns", &num_cols);
268	if (!num_rows || !num_cols) {
269		dev_err(dev, "number of keypad rows/columns not specified\n");
270		return ERR_PTR(-EINVAL);
271	}
272	pdata->rows = num_rows;
273	pdata->cols = num_cols;
274
275	keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
276	if (!keymap_data) {
277		dev_err(dev, "could not allocate memory for keymap data\n");
278		return ERR_PTR(-ENOMEM);
279	}
280	pdata->keymap_data = keymap_data;
281
282	key_count = of_get_child_count(np);
283	keymap_data->keymap_size = key_count;
284	keymap = devm_kzalloc(dev, sizeof(uint32_t) * key_count, GFP_KERNEL);
285	if (!keymap) {
286		dev_err(dev, "could not allocate memory for keymap\n");
287		return ERR_PTR(-ENOMEM);
288	}
289	keymap_data->keymap = keymap;
290
291	for_each_child_of_node(np, key_np) {
292		u32 row, col, key_code;
293		of_property_read_u32(key_np, "keypad,row", &row);
294		of_property_read_u32(key_np, "keypad,column", &col);
295		of_property_read_u32(key_np, "linux,code", &key_code);
296		*keymap++ = KEY(row, col, key_code);
297	}
298
299	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
300		pdata->no_autorepeat = true;
301
302	if (of_get_property(np, "linux,input-wakeup", NULL))
303		pdata->wakeup = true;
304
305	return pdata;
306}
307#else
308static struct samsung_keypad_platdata *
309samsung_keypad_parse_dt(struct device *dev)
310{
311	dev_err(dev, "no platform data defined\n");
312
313	return ERR_PTR(-EINVAL);
314}
315#endif
316
317static int samsung_keypad_probe(struct platform_device *pdev)
318{
319	const struct samsung_keypad_platdata *pdata;
320	const struct matrix_keymap_data *keymap_data;
321	struct samsung_keypad *keypad;
322	struct resource *res;
323	struct input_dev *input_dev;
324	unsigned int row_shift;
325	unsigned int keymap_size;
326	int error;
327
328	pdata = dev_get_platdata(&pdev->dev);
329	if (!pdata) {
330		pdata = samsung_keypad_parse_dt(&pdev->dev);
331		if (IS_ERR(pdata))
332			return PTR_ERR(pdata);
333	}
334
335	keymap_data = pdata->keymap_data;
336	if (!keymap_data) {
337		dev_err(&pdev->dev, "no keymap data defined\n");
338		return -EINVAL;
339	}
340
341	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
342		return -EINVAL;
343
344	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
345		return -EINVAL;
346
347	/* initialize the gpio */
348	if (pdata->cfg_gpio)
349		pdata->cfg_gpio(pdata->rows, pdata->cols);
350
351	row_shift = get_count_order(pdata->cols);
352	keymap_size = (pdata->rows << row_shift) * sizeof(keypad->keycodes[0]);
353
354	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad) + keymap_size,
355			      GFP_KERNEL);
356	input_dev = devm_input_allocate_device(&pdev->dev);
357	if (!keypad || !input_dev)
358		return -ENOMEM;
359
360	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
361	if (!res)
362		return -ENODEV;
363
364	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
365	if (!keypad->base)
366		return -EBUSY;
367
368	keypad->clk = devm_clk_get(&pdev->dev, "keypad");
369	if (IS_ERR(keypad->clk)) {
370		dev_err(&pdev->dev, "failed to get keypad clk\n");
371		return PTR_ERR(keypad->clk);
372	}
373
374	error = clk_prepare(keypad->clk);
375	if (error) {
376		dev_err(&pdev->dev, "keypad clock prepare failed\n");
377		return error;
378	}
379
380	keypad->input_dev = input_dev;
381	keypad->pdev = pdev;
382	keypad->row_shift = row_shift;
383	keypad->rows = pdata->rows;
384	keypad->cols = pdata->cols;
385	keypad->stopped = true;
386	init_waitqueue_head(&keypad->wait);
387
388	if (pdev->dev.of_node)
389		keypad->type = of_device_is_compatible(pdev->dev.of_node,
390					"samsung,s5pv210-keypad");
391	else
392		keypad->type = platform_get_device_id(pdev)->driver_data;
393
394	input_dev->name = pdev->name;
395	input_dev->id.bustype = BUS_HOST;
396	input_dev->dev.parent = &pdev->dev;
397
398	input_dev->open = samsung_keypad_open;
399	input_dev->close = samsung_keypad_close;
400
401	error = matrix_keypad_build_keymap(keymap_data, NULL,
402					   pdata->rows, pdata->cols,
403					   keypad->keycodes, input_dev);
404	if (error) {
405		dev_err(&pdev->dev, "failed to build keymap\n");
406		goto err_unprepare_clk;
407	}
408
409	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
410	if (!pdata->no_autorepeat)
411		__set_bit(EV_REP, input_dev->evbit);
412
413	input_set_drvdata(input_dev, keypad);
414
415	keypad->irq = platform_get_irq(pdev, 0);
416	if (keypad->irq < 0) {
417		error = keypad->irq;
418		goto err_unprepare_clk;
419	}
420
421	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
422					  samsung_keypad_irq, IRQF_ONESHOT,
423					  dev_name(&pdev->dev), keypad);
424	if (error) {
425		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
426		goto err_unprepare_clk;
427	}
428
429	device_init_wakeup(&pdev->dev, pdata->wakeup);
430	platform_set_drvdata(pdev, keypad);
431	pm_runtime_enable(&pdev->dev);
432
433	error = input_register_device(keypad->input_dev);
434	if (error)
435		goto err_disable_runtime_pm;
436
437	if (pdev->dev.of_node) {
438		devm_kfree(&pdev->dev, (void *)pdata->keymap_data->keymap);
439		devm_kfree(&pdev->dev, (void *)pdata->keymap_data);
440		devm_kfree(&pdev->dev, (void *)pdata);
441	}
442	return 0;
443
444err_disable_runtime_pm:
445	pm_runtime_disable(&pdev->dev);
446	device_init_wakeup(&pdev->dev, 0);
447err_unprepare_clk:
448	clk_unprepare(keypad->clk);
449	return error;
450}
451
452static int samsung_keypad_remove(struct platform_device *pdev)
453{
454	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
455
456	pm_runtime_disable(&pdev->dev);
457	device_init_wakeup(&pdev->dev, 0);
458
459	input_unregister_device(keypad->input_dev);
460
461	clk_unprepare(keypad->clk);
462
463	return 0;
464}
465
466#ifdef CONFIG_PM
467static int samsung_keypad_runtime_suspend(struct device *dev)
468{
469	struct platform_device *pdev = to_platform_device(dev);
470	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
471	unsigned int val;
472	int error;
473
474	if (keypad->stopped)
475		return 0;
476
477	/* This may fail on some SoCs due to lack of controller support */
478	error = enable_irq_wake(keypad->irq);
479	if (!error)
480		keypad->wake_enabled = true;
481
482	val = readl(keypad->base + SAMSUNG_KEYIFCON);
483	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
484	writel(val, keypad->base + SAMSUNG_KEYIFCON);
485
486	clk_disable(keypad->clk);
487
488	return 0;
489}
490
491static int samsung_keypad_runtime_resume(struct device *dev)
492{
493	struct platform_device *pdev = to_platform_device(dev);
494	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
495	unsigned int val;
496
497	if (keypad->stopped)
498		return 0;
499
500	clk_enable(keypad->clk);
501
502	val = readl(keypad->base + SAMSUNG_KEYIFCON);
503	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
504	writel(val, keypad->base + SAMSUNG_KEYIFCON);
505
506	if (keypad->wake_enabled)
507		disable_irq_wake(keypad->irq);
508
509	return 0;
510}
511#endif
512
513#ifdef CONFIG_PM_SLEEP
514static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
515					 bool enable)
516{
517	unsigned int val;
518
519	clk_enable(keypad->clk);
520
521	val = readl(keypad->base + SAMSUNG_KEYIFCON);
522	if (enable) {
523		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
524		if (device_may_wakeup(&keypad->pdev->dev))
525			enable_irq_wake(keypad->irq);
526	} else {
527		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
528		if (device_may_wakeup(&keypad->pdev->dev))
529			disable_irq_wake(keypad->irq);
530	}
531	writel(val, keypad->base + SAMSUNG_KEYIFCON);
532
533	clk_disable(keypad->clk);
534}
535
536static int samsung_keypad_suspend(struct device *dev)
537{
538	struct platform_device *pdev = to_platform_device(dev);
539	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
540	struct input_dev *input_dev = keypad->input_dev;
541
542	mutex_lock(&input_dev->mutex);
543
544	if (input_dev->users)
545		samsung_keypad_stop(keypad);
546
547	samsung_keypad_toggle_wakeup(keypad, true);
548
549	mutex_unlock(&input_dev->mutex);
550
551	return 0;
552}
553
554static int samsung_keypad_resume(struct device *dev)
555{
556	struct platform_device *pdev = to_platform_device(dev);
557	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
558	struct input_dev *input_dev = keypad->input_dev;
559
560	mutex_lock(&input_dev->mutex);
561
562	samsung_keypad_toggle_wakeup(keypad, false);
563
564	if (input_dev->users)
565		samsung_keypad_start(keypad);
566
567	mutex_unlock(&input_dev->mutex);
568
569	return 0;
570}
571#endif
572
573static const struct dev_pm_ops samsung_keypad_pm_ops = {
574	SET_SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
575	SET_RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
576			   samsung_keypad_runtime_resume, NULL)
577};
578
579#ifdef CONFIG_OF
580static const struct of_device_id samsung_keypad_dt_match[] = {
581	{ .compatible = "samsung,s3c6410-keypad" },
582	{ .compatible = "samsung,s5pv210-keypad" },
583	{},
584};
585MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
586#endif
587
588static struct platform_device_id samsung_keypad_driver_ids[] = {
589	{
590		.name		= "samsung-keypad",
591		.driver_data	= KEYPAD_TYPE_SAMSUNG,
592	}, {
593		.name		= "s5pv210-keypad",
594		.driver_data	= KEYPAD_TYPE_S5PV210,
595	},
596	{ },
597};
598MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
599
600static struct platform_driver samsung_keypad_driver = {
601	.probe		= samsung_keypad_probe,
602	.remove		= samsung_keypad_remove,
603	.driver		= {
604		.name	= "samsung-keypad",
605		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
606		.pm	= &samsung_keypad_pm_ops,
607	},
608	.id_table	= samsung_keypad_driver_ids,
609};
610module_platform_driver(samsung_keypad_driver);
611
612MODULE_DESCRIPTION("Samsung keypad driver");
613MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
614MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
615MODULE_LICENSE("GPL");
616