xref: /linux/drivers/input/keyboard/samsung-keypad.c (revision 0e9b70c1e3623fa110fb6be553e644524228ef60) 
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 
57 enum samsung_keypad_type {
58 	KEYPAD_TYPE_SAMSUNG,
59 	KEYPAD_TYPE_S5PV210,
60 };
61 
62 struct 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 
79 static 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 
105 static 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 
145 static 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 
172 static 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 
194 static 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 
224 static 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 
233 static 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
241 static struct samsung_keypad_platdata *
242 samsung_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 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
295 		pdata->no_autorepeat = true;
296 
297 	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
298 			/* legacy name */
299 			of_property_read_bool(np, "linux,input-wakeup");
300 
301 
302 	return pdata;
303 }
304 #else
305 static struct samsung_keypad_platdata *
306 samsung_keypad_parse_dt(struct device *dev)
307 {
308 	dev_err(dev, "no platform data defined\n");
309 
310 	return ERR_PTR(-EINVAL);
311 }
312 #endif
313 
314 static int samsung_keypad_probe(struct platform_device *pdev)
315 {
316 	const struct samsung_keypad_platdata *pdata;
317 	const struct matrix_keymap_data *keymap_data;
318 	struct samsung_keypad *keypad;
319 	struct resource *res;
320 	struct input_dev *input_dev;
321 	unsigned int row_shift;
322 	unsigned int keymap_size;
323 	int error;
324 
325 	pdata = dev_get_platdata(&pdev->dev);
326 	if (!pdata) {
327 		pdata = samsung_keypad_parse_dt(&pdev->dev);
328 		if (IS_ERR(pdata))
329 			return PTR_ERR(pdata);
330 	}
331 
332 	keymap_data = pdata->keymap_data;
333 	if (!keymap_data) {
334 		dev_err(&pdev->dev, "no keymap data defined\n");
335 		return -EINVAL;
336 	}
337 
338 	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
339 		return -EINVAL;
340 
341 	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
342 		return -EINVAL;
343 
344 	/* initialize the gpio */
345 	if (pdata->cfg_gpio)
346 		pdata->cfg_gpio(pdata->rows, pdata->cols);
347 
348 	row_shift = get_count_order(pdata->cols);
349 	keymap_size = (pdata->rows << row_shift) * sizeof(keypad->keycodes[0]);
350 
351 	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad) + keymap_size,
352 			      GFP_KERNEL);
353 	input_dev = devm_input_allocate_device(&pdev->dev);
354 	if (!keypad || !input_dev)
355 		return -ENOMEM;
356 
357 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
358 	if (!res)
359 		return -ENODEV;
360 
361 	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
362 	if (!keypad->base)
363 		return -EBUSY;
364 
365 	keypad->clk = devm_clk_get(&pdev->dev, "keypad");
366 	if (IS_ERR(keypad->clk)) {
367 		dev_err(&pdev->dev, "failed to get keypad clk\n");
368 		return PTR_ERR(keypad->clk);
369 	}
370 
371 	error = clk_prepare(keypad->clk);
372 	if (error) {
373 		dev_err(&pdev->dev, "keypad clock prepare failed\n");
374 		return error;
375 	}
376 
377 	keypad->input_dev = input_dev;
378 	keypad->pdev = pdev;
379 	keypad->row_shift = row_shift;
380 	keypad->rows = pdata->rows;
381 	keypad->cols = pdata->cols;
382 	keypad->stopped = true;
383 	init_waitqueue_head(&keypad->wait);
384 
385 	if (pdev->dev.of_node)
386 		keypad->type = of_device_is_compatible(pdev->dev.of_node,
387 					"samsung,s5pv210-keypad");
388 	else
389 		keypad->type = platform_get_device_id(pdev)->driver_data;
390 
391 	input_dev->name = pdev->name;
392 	input_dev->id.bustype = BUS_HOST;
393 	input_dev->dev.parent = &pdev->dev;
394 
395 	input_dev->open = samsung_keypad_open;
396 	input_dev->close = samsung_keypad_close;
397 
398 	error = matrix_keypad_build_keymap(keymap_data, NULL,
399 					   pdata->rows, pdata->cols,
400 					   keypad->keycodes, input_dev);
401 	if (error) {
402 		dev_err(&pdev->dev, "failed to build keymap\n");
403 		goto err_unprepare_clk;
404 	}
405 
406 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
407 	if (!pdata->no_autorepeat)
408 		__set_bit(EV_REP, input_dev->evbit);
409 
410 	input_set_drvdata(input_dev, keypad);
411 
412 	keypad->irq = platform_get_irq(pdev, 0);
413 	if (keypad->irq < 0) {
414 		error = keypad->irq;
415 		goto err_unprepare_clk;
416 	}
417 
418 	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
419 					  samsung_keypad_irq, IRQF_ONESHOT,
420 					  dev_name(&pdev->dev), keypad);
421 	if (error) {
422 		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
423 		goto err_unprepare_clk;
424 	}
425 
426 	device_init_wakeup(&pdev->dev, pdata->wakeup);
427 	platform_set_drvdata(pdev, keypad);
428 	pm_runtime_enable(&pdev->dev);
429 
430 	error = input_register_device(keypad->input_dev);
431 	if (error)
432 		goto err_disable_runtime_pm;
433 
434 	if (pdev->dev.of_node) {
435 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data->keymap);
436 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data);
437 		devm_kfree(&pdev->dev, (void *)pdata);
438 	}
439 	return 0;
440 
441 err_disable_runtime_pm:
442 	pm_runtime_disable(&pdev->dev);
443 err_unprepare_clk:
444 	clk_unprepare(keypad->clk);
445 	return error;
446 }
447 
448 static int samsung_keypad_remove(struct platform_device *pdev)
449 {
450 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
451 
452 	pm_runtime_disable(&pdev->dev);
453 
454 	input_unregister_device(keypad->input_dev);
455 
456 	clk_unprepare(keypad->clk);
457 
458 	return 0;
459 }
460 
461 static int samsung_keypad_runtime_suspend(struct device *dev)
462 {
463 	struct platform_device *pdev = to_platform_device(dev);
464 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
465 	unsigned int val;
466 	int error;
467 
468 	if (keypad->stopped)
469 		return 0;
470 
471 	/* This may fail on some SoCs due to lack of controller support */
472 	error = enable_irq_wake(keypad->irq);
473 	if (!error)
474 		keypad->wake_enabled = true;
475 
476 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
477 	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
478 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
479 
480 	clk_disable(keypad->clk);
481 
482 	return 0;
483 }
484 
485 static int samsung_keypad_runtime_resume(struct device *dev)
486 {
487 	struct platform_device *pdev = to_platform_device(dev);
488 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
489 	unsigned int val;
490 
491 	if (keypad->stopped)
492 		return 0;
493 
494 	clk_enable(keypad->clk);
495 
496 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
497 	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
498 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
499 
500 	if (keypad->wake_enabled)
501 		disable_irq_wake(keypad->irq);
502 
503 	return 0;
504 }
505 
506 static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
507 					 bool enable)
508 {
509 	unsigned int val;
510 
511 	clk_enable(keypad->clk);
512 
513 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
514 	if (enable) {
515 		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
516 		if (device_may_wakeup(&keypad->pdev->dev))
517 			enable_irq_wake(keypad->irq);
518 	} else {
519 		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
520 		if (device_may_wakeup(&keypad->pdev->dev))
521 			disable_irq_wake(keypad->irq);
522 	}
523 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
524 
525 	clk_disable(keypad->clk);
526 }
527 
528 static int samsung_keypad_suspend(struct device *dev)
529 {
530 	struct platform_device *pdev = to_platform_device(dev);
531 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
532 	struct input_dev *input_dev = keypad->input_dev;
533 
534 	mutex_lock(&input_dev->mutex);
535 
536 	if (input_device_enabled(input_dev))
537 		samsung_keypad_stop(keypad);
538 
539 	samsung_keypad_toggle_wakeup(keypad, true);
540 
541 	mutex_unlock(&input_dev->mutex);
542 
543 	return 0;
544 }
545 
546 static int samsung_keypad_resume(struct device *dev)
547 {
548 	struct platform_device *pdev = to_platform_device(dev);
549 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
550 	struct input_dev *input_dev = keypad->input_dev;
551 
552 	mutex_lock(&input_dev->mutex);
553 
554 	samsung_keypad_toggle_wakeup(keypad, false);
555 
556 	if (input_device_enabled(input_dev))
557 		samsung_keypad_start(keypad);
558 
559 	mutex_unlock(&input_dev->mutex);
560 
561 	return 0;
562 }
563 
564 static const struct dev_pm_ops samsung_keypad_pm_ops = {
565 	SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
566 	RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
567 		       samsung_keypad_runtime_resume, NULL)
568 };
569 
570 #ifdef CONFIG_OF
571 static const struct of_device_id samsung_keypad_dt_match[] = {
572 	{ .compatible = "samsung,s3c6410-keypad" },
573 	{ .compatible = "samsung,s5pv210-keypad" },
574 	{},
575 };
576 MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
577 #endif
578 
579 static const struct platform_device_id samsung_keypad_driver_ids[] = {
580 	{
581 		.name		= "samsung-keypad",
582 		.driver_data	= KEYPAD_TYPE_SAMSUNG,
583 	}, {
584 		.name		= "s5pv210-keypad",
585 		.driver_data	= KEYPAD_TYPE_S5PV210,
586 	},
587 	{ },
588 };
589 MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
590 
591 static struct platform_driver samsung_keypad_driver = {
592 	.probe		= samsung_keypad_probe,
593 	.remove		= samsung_keypad_remove,
594 	.driver		= {
595 		.name	= "samsung-keypad",
596 		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
597 		.pm	= pm_ptr(&samsung_keypad_pm_ops),
598 	},
599 	.id_table	= samsung_keypad_driver_ids,
600 };
601 module_platform_driver(samsung_keypad_driver);
602 
603 MODULE_DESCRIPTION("Samsung keypad driver");
604 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
605 MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
606 MODULE_LICENSE("GPL");
607