1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * OMAP4 Keypad Driver
4 *
5 * Copyright (C) 2010 Texas Instruments
6 *
7 * Author: Abraham Arce <x0066660@ti.com>
8 * Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
9 */
10
11#include <linux/module.h>
12#include <linux/interrupt.h>
13#include <linux/platform_device.h>
14#include <linux/errno.h>
15#include <linux/io.h>
16#include <linux/of.h>
17#include <linux/input.h>
18#include <linux/input/matrix_keypad.h>
19#include <linux/slab.h>
20#include <linux/pm_runtime.h>
21
22/* OMAP4 registers */
23#define OMAP4_KBD_REVISION		0x00
24#define OMAP4_KBD_SYSCONFIG		0x10
25#define OMAP4_KBD_SYSSTATUS		0x14
26#define OMAP4_KBD_IRQSTATUS		0x18
27#define OMAP4_KBD_IRQENABLE		0x1C
28#define OMAP4_KBD_WAKEUPENABLE		0x20
29#define OMAP4_KBD_PENDING		0x24
30#define OMAP4_KBD_CTRL			0x28
31#define OMAP4_KBD_DEBOUNCINGTIME	0x2C
32#define OMAP4_KBD_LONGKEYTIME		0x30
33#define OMAP4_KBD_TIMEOUT		0x34
34#define OMAP4_KBD_STATEMACHINE		0x38
35#define OMAP4_KBD_ROWINPUTS		0x3C
36#define OMAP4_KBD_COLUMNOUTPUTS		0x40
37#define OMAP4_KBD_FULLCODE31_0		0x44
38#define OMAP4_KBD_FULLCODE63_32		0x48
39
40/* OMAP4 bit definitions */
41#define OMAP4_DEF_IRQENABLE_EVENTEN	BIT(0)
42#define OMAP4_DEF_IRQENABLE_LONGKEY	BIT(1)
43#define OMAP4_DEF_WUP_EVENT_ENA		BIT(0)
44#define OMAP4_DEF_WUP_LONG_KEY_ENA	BIT(1)
45#define OMAP4_DEF_CTRL_NOSOFTMODE	BIT(1)
46#define OMAP4_DEF_CTRL_PTV_SHIFT	2
47
48/* OMAP4 values */
49#define OMAP4_VAL_IRQDISABLE		0x0
50
51/*
52 * Errata i689: If a key is released for a time shorter than debounce time,
53 * the keyboard will idle and never detect the key release. The workaround
54 * is to use at least a 12ms debounce time. See omap5432 TRM chapter
55 * "26.4.6.2 Keyboard Controller Timer" for more information.
56 */
57#define OMAP4_KEYPAD_PTV_DIV_128        0x6
58#define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv)     \
59	((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
60#define OMAP4_VAL_DEBOUNCINGTIME_16MS					\
61	OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)
62
63enum {
64	KBD_REVISION_OMAP4 = 0,
65	KBD_REVISION_OMAP5,
66};
67
68struct omap4_keypad {
69	struct input_dev *input;
70
71	void __iomem *base;
72	bool irq_wake_enabled;
73	unsigned int irq;
74
75	unsigned int rows;
76	unsigned int cols;
77	u32 reg_offset;
78	u32 irqreg_offset;
79	unsigned int row_shift;
80	bool no_autorepeat;
81	unsigned char key_state[8];
82	unsigned short *keymap;
83};
84
85static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
86{
87	return __raw_readl(keypad_data->base +
88				keypad_data->reg_offset + offset);
89}
90
91static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
92{
93	__raw_writel(value,
94		     keypad_data->base + keypad_data->reg_offset + offset);
95}
96
97static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
98{
99	return __raw_readl(keypad_data->base +
100				keypad_data->irqreg_offset + offset);
101}
102
103static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
104			     u32 offset, u32 value)
105{
106	__raw_writel(value,
107		     keypad_data->base + keypad_data->irqreg_offset + offset);
108}
109
110
111/* Interrupt handlers */
112static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
113{
114	struct omap4_keypad *keypad_data = dev_id;
115
116	if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
117		return IRQ_WAKE_THREAD;
118
119	return IRQ_NONE;
120}
121
122static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
123{
124	struct omap4_keypad *keypad_data = dev_id;
125	struct input_dev *input_dev = keypad_data->input;
126	unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
127	unsigned int col, row, code, changed;
128	u32 *new_state = (u32 *) key_state;
129
130	*new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
131	*(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
132
133	for (row = 0; row < keypad_data->rows; row++) {
134		changed = key_state[row] ^ keypad_data->key_state[row];
135		if (!changed)
136			continue;
137
138		for (col = 0; col < keypad_data->cols; col++) {
139			if (changed & (1 << col)) {
140				code = MATRIX_SCAN_CODE(row, col,
141						keypad_data->row_shift);
142				input_event(input_dev, EV_MSC, MSC_SCAN, code);
143				input_report_key(input_dev,
144						 keypad_data->keymap[code],
145						 key_state[row] & (1 << col));
146			}
147		}
148	}
149
150	input_sync(input_dev);
151
152	memcpy(keypad_data->key_state, key_state,
153		sizeof(keypad_data->key_state));
154
155	/* clear pending interrupts */
156	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
157			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
158
159	return IRQ_HANDLED;
160}
161
162static int omap4_keypad_open(struct input_dev *input)
163{
164	struct omap4_keypad *keypad_data = input_get_drvdata(input);
165
166	pm_runtime_get_sync(input->dev.parent);
167
168	disable_irq(keypad_data->irq);
169
170	kbd_writel(keypad_data, OMAP4_KBD_CTRL,
171			OMAP4_DEF_CTRL_NOSOFTMODE |
172			(OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
173	kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
174			OMAP4_VAL_DEBOUNCINGTIME_16MS);
175	/* clear pending interrupts */
176	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
177			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
178	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
179			OMAP4_DEF_IRQENABLE_EVENTEN |
180				OMAP4_DEF_IRQENABLE_LONGKEY);
181	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
182			OMAP4_DEF_WUP_EVENT_ENA | OMAP4_DEF_WUP_LONG_KEY_ENA);
183
184	enable_irq(keypad_data->irq);
185
186	return 0;
187}
188
189static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
190{
191	/* Disable interrupts and wake-up events */
192	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
193			 OMAP4_VAL_IRQDISABLE);
194	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
195
196	/* clear pending interrupts */
197	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
198			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
199}
200
201static void omap4_keypad_close(struct input_dev *input)
202{
203	struct omap4_keypad *keypad_data;
204
205	keypad_data = input_get_drvdata(input);
206	disable_irq(keypad_data->irq);
207	omap4_keypad_stop(keypad_data);
208	enable_irq(keypad_data->irq);
209
210	pm_runtime_put_sync(input->dev.parent);
211}
212
213static int omap4_keypad_parse_dt(struct device *dev,
214				 struct omap4_keypad *keypad_data)
215{
216	struct device_node *np = dev->of_node;
217	int err;
218
219	err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
220					     &keypad_data->cols);
221	if (err)
222		return err;
223
224	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
225		keypad_data->no_autorepeat = true;
226
227	return 0;
228}
229
230static int omap4_keypad_check_revision(struct device *dev,
231				       struct omap4_keypad *keypad_data)
232{
233	unsigned int rev;
234
235	rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
236	rev &= 0x03 << 30;
237	rev >>= 30;
238	switch (rev) {
239	case KBD_REVISION_OMAP4:
240		keypad_data->reg_offset = 0x00;
241		keypad_data->irqreg_offset = 0x00;
242		break;
243	case KBD_REVISION_OMAP5:
244		keypad_data->reg_offset = 0x10;
245		keypad_data->irqreg_offset = 0x0c;
246		break;
247	default:
248		dev_err(dev, "Keypad reports unsupported revision %d", rev);
249		return -EINVAL;
250	}
251
252	return 0;
253}
254
255static int omap4_keypad_probe(struct platform_device *pdev)
256{
257	struct omap4_keypad *keypad_data;
258	struct input_dev *input_dev;
259	struct resource *res;
260	unsigned int max_keys;
261	int irq;
262	int error;
263
264	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
265	if (!res) {
266		dev_err(&pdev->dev, "no base address specified\n");
267		return -EINVAL;
268	}
269
270	irq = platform_get_irq(pdev, 0);
271	if (irq < 0)
272		return irq;
273
274	keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
275	if (!keypad_data) {
276		dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
277		return -ENOMEM;
278	}
279
280	keypad_data->irq = irq;
281
282	error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
283	if (error)
284		goto err_free_keypad;
285
286	res = request_mem_region(res->start, resource_size(res), pdev->name);
287	if (!res) {
288		dev_err(&pdev->dev, "can't request mem region\n");
289		error = -EBUSY;
290		goto err_free_keypad;
291	}
292
293	keypad_data->base = ioremap(res->start, resource_size(res));
294	if (!keypad_data->base) {
295		dev_err(&pdev->dev, "can't ioremap mem resource\n");
296		error = -ENOMEM;
297		goto err_release_mem;
298	}
299
300	pm_runtime_enable(&pdev->dev);
301
302	/*
303	 * Enable clocks for the keypad module so that we can read
304	 * revision register.
305	 */
306	error = pm_runtime_get_sync(&pdev->dev);
307	if (error) {
308		dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
309		pm_runtime_put_noidle(&pdev->dev);
310	} else {
311		error = omap4_keypad_check_revision(&pdev->dev,
312						    keypad_data);
313		if (!error) {
314			/* Ensure device does not raise interrupts */
315			omap4_keypad_stop(keypad_data);
316		}
317		pm_runtime_put_sync(&pdev->dev);
318	}
319	if (error)
320		goto err_pm_disable;
321
322	/* input device allocation */
323	keypad_data->input = input_dev = input_allocate_device();
324	if (!input_dev) {
325		error = -ENOMEM;
326		goto err_pm_disable;
327	}
328
329	input_dev->name = pdev->name;
330	input_dev->dev.parent = &pdev->dev;
331	input_dev->id.bustype = BUS_HOST;
332	input_dev->id.vendor = 0x0001;
333	input_dev->id.product = 0x0001;
334	input_dev->id.version = 0x0001;
335
336	input_dev->open = omap4_keypad_open;
337	input_dev->close = omap4_keypad_close;
338
339	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
340	if (!keypad_data->no_autorepeat)
341		__set_bit(EV_REP, input_dev->evbit);
342
343	input_set_drvdata(input_dev, keypad_data);
344
345	keypad_data->row_shift = get_count_order(keypad_data->cols);
346	max_keys = keypad_data->rows << keypad_data->row_shift;
347	keypad_data->keymap = kcalloc(max_keys,
348				      sizeof(keypad_data->keymap[0]),
349				      GFP_KERNEL);
350	if (!keypad_data->keymap) {
351		dev_err(&pdev->dev, "Not enough memory for keymap\n");
352		error = -ENOMEM;
353		goto err_free_input;
354	}
355
356	error = matrix_keypad_build_keymap(NULL, NULL,
357					   keypad_data->rows, keypad_data->cols,
358					   keypad_data->keymap, input_dev);
359	if (error) {
360		dev_err(&pdev->dev, "failed to build keymap\n");
361		goto err_free_keymap;
362	}
363
364	error = request_threaded_irq(keypad_data->irq, omap4_keypad_irq_handler,
365				     omap4_keypad_irq_thread_fn, IRQF_ONESHOT,
366				     "omap4-keypad", keypad_data);
367	if (error) {
368		dev_err(&pdev->dev, "failed to register interrupt\n");
369		goto err_free_keymap;
370	}
371
372	error = input_register_device(keypad_data->input);
373	if (error < 0) {
374		dev_err(&pdev->dev, "failed to register input device\n");
375		goto err_free_irq;
376	}
377
378	device_init_wakeup(&pdev->dev, true);
379	platform_set_drvdata(pdev, keypad_data);
380
381	return 0;
382
383err_free_irq:
384	free_irq(keypad_data->irq, keypad_data);
385err_free_keymap:
386	kfree(keypad_data->keymap);
387err_free_input:
388	input_free_device(input_dev);
389err_pm_disable:
390	pm_runtime_disable(&pdev->dev);
391	iounmap(keypad_data->base);
392err_release_mem:
393	release_mem_region(res->start, resource_size(res));
394err_free_keypad:
395	kfree(keypad_data);
396	return error;
397}
398
399static int omap4_keypad_remove(struct platform_device *pdev)
400{
401	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
402	struct resource *res;
403
404	free_irq(keypad_data->irq, keypad_data);
405
406	pm_runtime_disable(&pdev->dev);
407
408	input_unregister_device(keypad_data->input);
409
410	iounmap(keypad_data->base);
411
412	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
413	release_mem_region(res->start, resource_size(res));
414
415	kfree(keypad_data->keymap);
416	kfree(keypad_data);
417
418	return 0;
419}
420
421static const struct of_device_id omap_keypad_dt_match[] = {
422	{ .compatible = "ti,omap4-keypad" },
423	{},
424};
425MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
426
427#ifdef CONFIG_PM_SLEEP
428static int omap4_keypad_suspend(struct device *dev)
429{
430	struct platform_device *pdev = to_platform_device(dev);
431	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
432	int error;
433
434	if (device_may_wakeup(&pdev->dev)) {
435		error = enable_irq_wake(keypad_data->irq);
436		if (!error)
437			keypad_data->irq_wake_enabled = true;
438	}
439
440	return 0;
441}
442
443static int omap4_keypad_resume(struct device *dev)
444{
445	struct platform_device *pdev = to_platform_device(dev);
446	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
447
448	if (device_may_wakeup(&pdev->dev) && keypad_data->irq_wake_enabled) {
449		disable_irq_wake(keypad_data->irq);
450		keypad_data->irq_wake_enabled = false;
451	}
452
453	return 0;
454}
455#endif
456
457static SIMPLE_DEV_PM_OPS(omap4_keypad_pm_ops,
458			 omap4_keypad_suspend, omap4_keypad_resume);
459
460static struct platform_driver omap4_keypad_driver = {
461	.probe		= omap4_keypad_probe,
462	.remove		= omap4_keypad_remove,
463	.driver		= {
464		.name	= "omap4-keypad",
465		.pm	= &omap4_keypad_pm_ops,
466		.of_match_table = omap_keypad_dt_match,
467	},
468};
469module_platform_driver(omap4_keypad_driver);
470
471MODULE_AUTHOR("Texas Instruments");
472MODULE_DESCRIPTION("OMAP4 Keypad Driver");
473MODULE_LICENSE("GPL");
474MODULE_ALIAS("platform:omap4-keypad");
475