xref: /linux/drivers/input/keyboard/omap4-keypad.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a) 
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 #include <linux/pm_wakeirq.h>
22 
23 /* OMAP4 registers */
24 #define OMAP4_KBD_REVISION		0x00
25 #define OMAP4_KBD_SYSCONFIG		0x10
26 #define OMAP4_KBD_SYSSTATUS		0x14
27 #define OMAP4_KBD_IRQSTATUS		0x18
28 #define OMAP4_KBD_IRQENABLE		0x1C
29 #define OMAP4_KBD_WAKEUPENABLE		0x20
30 #define OMAP4_KBD_PENDING		0x24
31 #define OMAP4_KBD_CTRL			0x28
32 #define OMAP4_KBD_DEBOUNCINGTIME	0x2C
33 #define OMAP4_KBD_LONGKEYTIME		0x30
34 #define OMAP4_KBD_TIMEOUT		0x34
35 #define OMAP4_KBD_STATEMACHINE		0x38
36 #define OMAP4_KBD_ROWINPUTS		0x3C
37 #define OMAP4_KBD_COLUMNOUTPUTS		0x40
38 #define OMAP4_KBD_FULLCODE31_0		0x44
39 #define OMAP4_KBD_FULLCODE63_32		0x48
40 
41 /* OMAP4 bit definitions */
42 #define OMAP4_DEF_IRQENABLE_EVENTEN	BIT(0)
43 #define OMAP4_DEF_IRQENABLE_LONGKEY	BIT(1)
44 #define OMAP4_DEF_WUP_EVENT_ENA		BIT(0)
45 #define OMAP4_DEF_WUP_LONG_KEY_ENA	BIT(1)
46 #define OMAP4_DEF_CTRL_NOSOFTMODE	BIT(1)
47 #define OMAP4_DEF_CTRL_PTV_SHIFT	2
48 
49 /* OMAP4 values */
50 #define OMAP4_VAL_IRQDISABLE		0x0
51 
52 /*
53  * Errata i689: If a key is released for a time shorter than debounce time,
54  * the keyboard will idle and never detect the key release. The workaround
55  * is to use at least a 12ms debounce time. See omap5432 TRM chapter
56  * "26.4.6.2 Keyboard Controller Timer" for more information.
57  */
58 #define OMAP4_KEYPAD_PTV_DIV_128        0x6
59 #define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv)     \
60 	((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
61 #define OMAP4_VAL_DEBOUNCINGTIME_16MS					\
62 	OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)
63 #define OMAP4_KEYPAD_AUTOIDLE_MS	50	/* Approximate measured time */
64 #define OMAP4_KEYPAD_IDLE_CHECK_MS	(OMAP4_KEYPAD_AUTOIDLE_MS / 2)
65 
66 enum {
67 	KBD_REVISION_OMAP4 = 0,
68 	KBD_REVISION_OMAP5,
69 };
70 
71 struct omap4_keypad {
72 	struct input_dev *input;
73 
74 	void __iomem *base;
75 	unsigned int irq;
76 	struct mutex lock;		/* for key scan */
77 
78 	unsigned int rows;
79 	unsigned int cols;
80 	u32 reg_offset;
81 	u32 irqreg_offset;
82 	unsigned int row_shift;
83 	bool no_autorepeat;
84 	u64 keys;
85 	unsigned short *keymap;
86 };
87 
88 static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
89 {
90 	return __raw_readl(keypad_data->base +
91 				keypad_data->reg_offset + offset);
92 }
93 
94 static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
95 {
96 	__raw_writel(value,
97 		     keypad_data->base + keypad_data->reg_offset + offset);
98 }
99 
100 static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
101 {
102 	return __raw_readl(keypad_data->base +
103 				keypad_data->irqreg_offset + offset);
104 }
105 
106 static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
107 			     u32 offset, u32 value)
108 {
109 	__raw_writel(value,
110 		     keypad_data->base + keypad_data->irqreg_offset + offset);
111 }
112 
113 static int omap4_keypad_report_keys(struct omap4_keypad *keypad_data,
114 				    u64 keys, bool down)
115 {
116 	struct input_dev *input_dev = keypad_data->input;
117 	unsigned int col, row, code;
118 	DECLARE_BITMAP(mask, 64);
119 	unsigned long bit;
120 	int events = 0;
121 
122 	bitmap_from_u64(mask, keys);
123 
124 	for_each_set_bit(bit, mask, keypad_data->rows * BITS_PER_BYTE) {
125 		row = bit / BITS_PER_BYTE;
126 		col = bit % BITS_PER_BYTE;
127 		code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift);
128 
129 		input_event(input_dev, EV_MSC, MSC_SCAN, code);
130 		input_report_key(input_dev, keypad_data->keymap[code], down);
131 
132 		events++;
133 	}
134 
135 	if (events)
136 		input_sync(input_dev);
137 
138 	return events;
139 }
140 
141 static void omap4_keypad_scan_keys(struct omap4_keypad *keypad_data, u64 keys)
142 {
143 	u64 changed;
144 
145 	mutex_lock(&keypad_data->lock);
146 
147 	changed = keys ^ keypad_data->keys;
148 
149 	/*
150 	 * Report key up events separately and first. This matters in case we
151 	 * lost key-up interrupt and just now catching up.
152 	 */
153 	omap4_keypad_report_keys(keypad_data, changed & ~keys, false);
154 
155 	/* Report key down events */
156 	omap4_keypad_report_keys(keypad_data, changed & keys, true);
157 
158 	keypad_data->keys = keys;
159 
160 	mutex_unlock(&keypad_data->lock);
161 }
162 
163 /* Interrupt handlers */
164 static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
165 {
166 	struct omap4_keypad *keypad_data = dev_id;
167 
168 	if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
169 		return IRQ_WAKE_THREAD;
170 
171 	return IRQ_NONE;
172 }
173 
174 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
175 {
176 	struct omap4_keypad *keypad_data = dev_id;
177 	struct device *dev = keypad_data->input->dev.parent;
178 	u32 low, high;
179 	int error;
180 	u64 keys;
181 
182 	error = pm_runtime_get_sync(dev);
183 	if (error < 0) {
184 		pm_runtime_put_noidle(dev);
185 		return IRQ_NONE;
186 	}
187 
188 	low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
189 	high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
190 	keys = low | (u64)high << 32;
191 
192 	omap4_keypad_scan_keys(keypad_data, keys);
193 
194 	/* clear pending interrupts */
195 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
196 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
197 
198 	pm_runtime_mark_last_busy(dev);
199 	pm_runtime_put_autosuspend(dev);
200 
201 	return IRQ_HANDLED;
202 }
203 
204 static int omap4_keypad_open(struct input_dev *input)
205 {
206 	struct omap4_keypad *keypad_data = input_get_drvdata(input);
207 	struct device *dev = input->dev.parent;
208 	int error;
209 
210 	error = pm_runtime_get_sync(dev);
211 	if (error < 0) {
212 		pm_runtime_put_noidle(dev);
213 		return error;
214 	}
215 
216 	disable_irq(keypad_data->irq);
217 
218 	kbd_writel(keypad_data, OMAP4_KBD_CTRL,
219 			OMAP4_DEF_CTRL_NOSOFTMODE |
220 			(OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
221 	kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
222 			OMAP4_VAL_DEBOUNCINGTIME_16MS);
223 	/* clear pending interrupts */
224 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
225 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
226 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
227 			OMAP4_DEF_IRQENABLE_EVENTEN);
228 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
229 			OMAP4_DEF_WUP_EVENT_ENA);
230 
231 	enable_irq(keypad_data->irq);
232 
233 	pm_runtime_mark_last_busy(dev);
234 	pm_runtime_put_autosuspend(dev);
235 
236 	return 0;
237 }
238 
239 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
240 {
241 	/* Disable interrupts and wake-up events */
242 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
243 			 OMAP4_VAL_IRQDISABLE);
244 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
245 
246 	/* clear pending interrupts */
247 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
248 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
249 }
250 
251 static void omap4_keypad_close(struct input_dev *input)
252 {
253 	struct omap4_keypad *keypad_data = input_get_drvdata(input);
254 	struct device *dev = input->dev.parent;
255 	int error;
256 
257 	error = pm_runtime_get_sync(dev);
258 	if (error < 0)
259 		pm_runtime_put_noidle(dev);
260 
261 	disable_irq(keypad_data->irq);
262 	omap4_keypad_stop(keypad_data);
263 	enable_irq(keypad_data->irq);
264 
265 	pm_runtime_mark_last_busy(dev);
266 	pm_runtime_put_autosuspend(dev);
267 }
268 
269 static int omap4_keypad_parse_dt(struct device *dev,
270 				 struct omap4_keypad *keypad_data)
271 {
272 	struct device_node *np = dev->of_node;
273 	int err;
274 
275 	err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
276 					     &keypad_data->cols);
277 	if (err)
278 		return err;
279 
280 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
281 		keypad_data->no_autorepeat = true;
282 
283 	return 0;
284 }
285 
286 static int omap4_keypad_check_revision(struct device *dev,
287 				       struct omap4_keypad *keypad_data)
288 {
289 	unsigned int rev;
290 
291 	rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
292 	rev &= 0x03 << 30;
293 	rev >>= 30;
294 	switch (rev) {
295 	case KBD_REVISION_OMAP4:
296 		keypad_data->reg_offset = 0x00;
297 		keypad_data->irqreg_offset = 0x00;
298 		break;
299 	case KBD_REVISION_OMAP5:
300 		keypad_data->reg_offset = 0x10;
301 		keypad_data->irqreg_offset = 0x0c;
302 		break;
303 	default:
304 		dev_err(dev, "Keypad reports unsupported revision %d", rev);
305 		return -EINVAL;
306 	}
307 
308 	return 0;
309 }
310 
311 /*
312  * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed".
313  * Interrupt may not happen for key-up events. We must clear stuck
314  * key-up events after the keyboard hardware has auto-idled.
315  */
316 static int __maybe_unused omap4_keypad_runtime_suspend(struct device *dev)
317 {
318 	struct platform_device *pdev = to_platform_device(dev);
319 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
320 	u32 active;
321 
322 	active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE);
323 	if (active) {
324 		pm_runtime_mark_last_busy(dev);
325 		return -EBUSY;
326 	}
327 
328 	omap4_keypad_scan_keys(keypad_data, 0);
329 
330 	return 0;
331 }
332 
333 static const struct dev_pm_ops omap4_keypad_pm_ops = {
334 	SET_RUNTIME_PM_OPS(omap4_keypad_runtime_suspend, NULL, NULL)
335 };
336 
337 static void omap4_disable_pm(void *d)
338 {
339 	pm_runtime_dont_use_autosuspend(d);
340 	pm_runtime_disable(d);
341 }
342 
343 static int omap4_keypad_probe(struct platform_device *pdev)
344 {
345 	struct device *dev = &pdev->dev;
346 	struct omap4_keypad *keypad_data;
347 	struct input_dev *input_dev;
348 	struct resource *res;
349 	unsigned int max_keys;
350 	int irq;
351 	int error;
352 
353 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
354 	if (!res) {
355 		dev_err(&pdev->dev, "no base address specified\n");
356 		return -EINVAL;
357 	}
358 
359 	irq = platform_get_irq(pdev, 0);
360 	if (irq < 0)
361 		return irq;
362 
363 	keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
364 	if (!keypad_data) {
365 		dev_err(dev, "keypad_data memory allocation failed\n");
366 		return -ENOMEM;
367 	}
368 
369 	keypad_data->irq = irq;
370 	mutex_init(&keypad_data->lock);
371 	platform_set_drvdata(pdev, keypad_data);
372 
373 	error = omap4_keypad_parse_dt(dev, keypad_data);
374 	if (error)
375 		return error;
376 
377 	keypad_data->base = devm_ioremap_resource(dev, res);
378 	if (IS_ERR(keypad_data->base))
379 		return PTR_ERR(keypad_data->base);
380 
381 	pm_runtime_use_autosuspend(dev);
382 	pm_runtime_set_autosuspend_delay(dev, OMAP4_KEYPAD_IDLE_CHECK_MS);
383 	pm_runtime_enable(dev);
384 
385 	error = devm_add_action_or_reset(dev, omap4_disable_pm, dev);
386 	if (error) {
387 		dev_err(dev, "unable to register cleanup action\n");
388 		return error;
389 	}
390 
391 	/*
392 	 * Enable clocks for the keypad module so that we can read
393 	 * revision register.
394 	 */
395 	error = pm_runtime_get_sync(dev);
396 	if (error) {
397 		dev_err(dev, "pm_runtime_get_sync() failed\n");
398 		pm_runtime_put_noidle(dev);
399 		return error;
400 	}
401 
402 	error = omap4_keypad_check_revision(dev, keypad_data);
403 	if (!error) {
404 		/* Ensure device does not raise interrupts */
405 		omap4_keypad_stop(keypad_data);
406 	}
407 
408 	pm_runtime_mark_last_busy(dev);
409 	pm_runtime_put_autosuspend(dev);
410 	if (error)
411 		return error;
412 
413 	/* input device allocation */
414 	keypad_data->input = input_dev = devm_input_allocate_device(dev);
415 	if (!input_dev)
416 		return -ENOMEM;
417 
418 	input_dev->name = pdev->name;
419 	input_dev->id.bustype = BUS_HOST;
420 	input_dev->id.vendor = 0x0001;
421 	input_dev->id.product = 0x0001;
422 	input_dev->id.version = 0x0001;
423 
424 	input_dev->open = omap4_keypad_open;
425 	input_dev->close = omap4_keypad_close;
426 
427 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
428 	if (!keypad_data->no_autorepeat)
429 		__set_bit(EV_REP, input_dev->evbit);
430 
431 	input_set_drvdata(input_dev, keypad_data);
432 
433 	keypad_data->row_shift = get_count_order(keypad_data->cols);
434 	max_keys = keypad_data->rows << keypad_data->row_shift;
435 	keypad_data->keymap = devm_kcalloc(dev,
436 					   max_keys,
437 					   sizeof(keypad_data->keymap[0]),
438 					   GFP_KERNEL);
439 	if (!keypad_data->keymap) {
440 		dev_err(dev, "Not enough memory for keymap\n");
441 		return -ENOMEM;
442 	}
443 
444 	error = matrix_keypad_build_keymap(NULL, NULL,
445 					   keypad_data->rows, keypad_data->cols,
446 					   keypad_data->keymap, input_dev);
447 	if (error) {
448 		dev_err(dev, "failed to build keymap\n");
449 		return error;
450 	}
451 
452 	error = devm_request_threaded_irq(dev, keypad_data->irq,
453 					  omap4_keypad_irq_handler,
454 					  omap4_keypad_irq_thread_fn,
455 					  IRQF_ONESHOT,
456 					  "omap4-keypad", keypad_data);
457 	if (error) {
458 		dev_err(dev, "failed to register interrupt\n");
459 		return error;
460 	}
461 
462 	error = input_register_device(keypad_data->input);
463 	if (error) {
464 		dev_err(dev, "failed to register input device\n");
465 		return error;
466 	}
467 
468 	device_init_wakeup(dev, true);
469 	error = dev_pm_set_wake_irq(dev, keypad_data->irq);
470 	if (error)
471 		dev_warn(dev, "failed to set up wakeup irq: %d\n", error);
472 
473 	return 0;
474 }
475 
476 static int omap4_keypad_remove(struct platform_device *pdev)
477 {
478 	dev_pm_clear_wake_irq(&pdev->dev);
479 
480 	return 0;
481 }
482 
483 static const struct of_device_id omap_keypad_dt_match[] = {
484 	{ .compatible = "ti,omap4-keypad" },
485 	{},
486 };
487 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
488 
489 static struct platform_driver omap4_keypad_driver = {
490 	.probe		= omap4_keypad_probe,
491 	.remove		= omap4_keypad_remove,
492 	.driver		= {
493 		.name	= "omap4-keypad",
494 		.of_match_table = omap_keypad_dt_match,
495 		.pm = &omap4_keypad_pm_ops,
496 	},
497 };
498 module_platform_driver(omap4_keypad_driver);
499 
500 MODULE_AUTHOR("Texas Instruments");
501 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
502 MODULE_LICENSE("GPL");
503 MODULE_ALIAS("platform:omap4-keypad");
504