xref: /linux/drivers/input/keyboard/samsung-keypad.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d) 
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/bits.h>
11 #include <linux/clk.h>
12 #include <linux/delay.h>
13 #include <linux/err.h>
14 #include <linux/input.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <linux/sched.h>
24 #include <linux/input/samsung-keypad.h>
25 
26 #define SAMSUNG_KEYIFCON			0x00
27 #define SAMSUNG_KEYIFSTSCLR			0x04
28 #define SAMSUNG_KEYIFCOL			0x08
29 #define SAMSUNG_KEYIFROW			0x0c
30 #define SAMSUNG_KEYIFFC				0x10
31 
32 /* SAMSUNG_KEYIFCON */
33 #define SAMSUNG_KEYIFCON_INT_F_EN		BIT(0)
34 #define SAMSUNG_KEYIFCON_INT_R_EN		BIT(1)
35 #define SAMSUNG_KEYIFCON_DF_EN			BIT(2)
36 #define SAMSUNG_KEYIFCON_FC_EN			BIT(3)
37 #define SAMSUNG_KEYIFCON_WAKEUPEN		BIT(4)
38 
39 /* SAMSUNG_KEYIFSTSCLR */
40 #define SAMSUNG_KEYIFSTSCLR_P_INT_MASK		(0xff << 0)
41 #define SAMSUNG_KEYIFSTSCLR_R_INT_MASK		(0xff << 8)
42 #define SAMSUNG_KEYIFSTSCLR_R_INT_OFFSET	8
43 #define S5PV210_KEYIFSTSCLR_P_INT_MASK		(0x3fff << 0)
44 #define S5PV210_KEYIFSTSCLR_R_INT_MASK		(0x3fff << 16)
45 #define S5PV210_KEYIFSTSCLR_R_INT_OFFSET	16
46 
47 /* SAMSUNG_KEYIFCOL */
48 #define SAMSUNG_KEYIFCOL_MASK			0xff
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 struct samsung_chip_info {
58 	unsigned int column_shift;
59 };
60 
61 struct samsung_keypad {
62 	const struct samsung_chip_info *chip;
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 	unsigned int row_shift;
72 	unsigned int rows;
73 	unsigned int cols;
74 	unsigned int row_state[SAMSUNG_MAX_COLS];
75 	unsigned short keycodes[];
76 };
77 
78 static void samsung_keypad_scan(struct samsung_keypad *keypad,
79 				unsigned int *row_state)
80 {
81 	unsigned int col;
82 	unsigned int val;
83 
84 	for (col = 0; col < keypad->cols; col++) {
85 		val = SAMSUNG_KEYIFCOL_MASK & ~BIT(col);
86 		val <<= keypad->chip->column_shift;
87 
88 		writel(val, keypad->base + SAMSUNG_KEYIFCOL);
89 		mdelay(1);
90 
91 		val = readl(keypad->base + SAMSUNG_KEYIFROW);
92 		row_state[col] = ~val & GENMASK(keypad->rows - 1, 0);
93 	}
94 
95 	/* KEYIFCOL reg clear */
96 	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
97 }
98 
99 static bool samsung_keypad_report(struct samsung_keypad *keypad,
100 				  unsigned int *row_state)
101 {
102 	struct input_dev *input_dev = keypad->input_dev;
103 	unsigned int changed;
104 	unsigned int pressed;
105 	unsigned int key_down = 0;
106 	unsigned int val;
107 	unsigned int col, row;
108 
109 	for (col = 0; col < keypad->cols; col++) {
110 		changed = row_state[col] ^ keypad->row_state[col];
111 		key_down |= row_state[col];
112 		if (!changed)
113 			continue;
114 
115 		for (row = 0; row < keypad->rows; row++) {
116 			if (!(changed & BIT(row)))
117 				continue;
118 
119 			pressed = row_state[col] & BIT(row);
120 
121 			dev_dbg(&keypad->input_dev->dev,
122 				"key %s, row: %d, col: %d\n",
123 				pressed ? "pressed" : "released", row, col);
124 
125 			val = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
126 
127 			input_event(input_dev, EV_MSC, MSC_SCAN, val);
128 			input_report_key(input_dev,
129 					keypad->keycodes[val], pressed);
130 		}
131 		input_sync(keypad->input_dev);
132 	}
133 
134 	memcpy(keypad->row_state, row_state, sizeof(keypad->row_state));
135 
136 	return key_down;
137 }
138 
139 static irqreturn_t samsung_keypad_irq(int irq, void *dev_id)
140 {
141 	struct samsung_keypad *keypad = dev_id;
142 	unsigned int row_state[SAMSUNG_MAX_COLS];
143 	bool key_down;
144 
145 	guard(pm_runtime_active)(&keypad->pdev->dev);
146 
147 	do {
148 		readl(keypad->base + SAMSUNG_KEYIFSTSCLR);
149 		/* Clear interrupt. */
150 		writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
151 
152 		samsung_keypad_scan(keypad, row_state);
153 
154 		key_down = samsung_keypad_report(keypad, row_state);
155 		if (key_down)
156 			wait_event_timeout(keypad->wait, keypad->stopped,
157 					   msecs_to_jiffies(50));
158 
159 	} while (key_down && !keypad->stopped);
160 
161 	return IRQ_HANDLED;
162 }
163 
164 static void samsung_keypad_start(struct samsung_keypad *keypad)
165 {
166 	unsigned int val;
167 
168 	guard(pm_runtime_active)(&keypad->pdev->dev);
169 
170 	/* Tell IRQ thread that it may poll the device. */
171 	keypad->stopped = false;
172 
173 	clk_enable(keypad->clk);
174 
175 	/* Enable interrupt bits. */
176 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
177 	val |= SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN;
178 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
179 
180 	/* KEYIFCOL reg clear. */
181 	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
182 
183 	enable_irq(keypad->irq);
184 }
185 
186 static void samsung_keypad_stop(struct samsung_keypad *keypad)
187 {
188 	unsigned int val;
189 
190 	guard(pm_runtime_active)(&keypad->pdev->dev);
191 
192 	/* Signal IRQ thread to stop polling and disable the handler. */
193 	keypad->stopped = true;
194 	wake_up(&keypad->wait);
195 	disable_irq(keypad->irq);
196 
197 	/* Clear interrupt. */
198 	writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
199 
200 	/* Disable interrupt bits. */
201 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
202 	val &= ~(SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN);
203 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
204 
205 	clk_disable(keypad->clk);
206 }
207 
208 static int samsung_keypad_open(struct input_dev *input_dev)
209 {
210 	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
211 
212 	samsung_keypad_start(keypad);
213 
214 	return 0;
215 }
216 
217 static void samsung_keypad_close(struct input_dev *input_dev)
218 {
219 	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
220 
221 	samsung_keypad_stop(keypad);
222 }
223 
224 #ifdef CONFIG_OF
225 static struct samsung_keypad_platdata *
226 samsung_keypad_parse_dt(struct device *dev)
227 {
228 	struct samsung_keypad_platdata *pdata;
229 	struct matrix_keymap_data *keymap_data;
230 	uint32_t *keymap, num_rows = 0, num_cols = 0;
231 	struct device_node *np = dev->of_node, *key_np;
232 	unsigned int key_count;
233 
234 	if (!np) {
235 		dev_err(dev, "missing device tree data\n");
236 		return ERR_PTR(-EINVAL);
237 	}
238 
239 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
240 	if (!pdata) {
241 		dev_err(dev, "could not allocate memory for platform data\n");
242 		return ERR_PTR(-ENOMEM);
243 	}
244 
245 	of_property_read_u32(np, "samsung,keypad-num-rows", &num_rows);
246 	of_property_read_u32(np, "samsung,keypad-num-columns", &num_cols);
247 	if (!num_rows || !num_cols) {
248 		dev_err(dev, "number of keypad rows/columns not specified\n");
249 		return ERR_PTR(-EINVAL);
250 	}
251 	pdata->rows = num_rows;
252 	pdata->cols = num_cols;
253 
254 	keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
255 	if (!keymap_data) {
256 		dev_err(dev, "could not allocate memory for keymap data\n");
257 		return ERR_PTR(-ENOMEM);
258 	}
259 	pdata->keymap_data = keymap_data;
260 
261 	key_count = of_get_child_count(np);
262 	keymap_data->keymap_size = key_count;
263 	keymap = devm_kcalloc(dev, key_count, sizeof(uint32_t), GFP_KERNEL);
264 	if (!keymap) {
265 		dev_err(dev, "could not allocate memory for keymap\n");
266 		return ERR_PTR(-ENOMEM);
267 	}
268 	keymap_data->keymap = keymap;
269 
270 	for_each_child_of_node(np, key_np) {
271 		u32 row, col, key_code;
272 		of_property_read_u32(key_np, "keypad,row", &row);
273 		of_property_read_u32(key_np, "keypad,column", &col);
274 		of_property_read_u32(key_np, "linux,code", &key_code);
275 		*keymap++ = KEY(row, col, key_code);
276 	}
277 
278 	pdata->no_autorepeat = of_property_read_bool(np, "linux,input-no-autorepeat");
279 
280 	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
281 			/* legacy name */
282 			of_property_read_bool(np, "linux,input-wakeup");
283 
284 
285 	return pdata;
286 }
287 #else
288 static struct samsung_keypad_platdata *
289 samsung_keypad_parse_dt(struct device *dev)
290 {
291 	dev_err(dev, "no platform data defined\n");
292 
293 	return ERR_PTR(-EINVAL);
294 }
295 #endif
296 
297 static int samsung_keypad_probe(struct platform_device *pdev)
298 {
299 	const struct samsung_keypad_platdata *pdata;
300 	const struct matrix_keymap_data *keymap_data;
301 	const struct platform_device_id *id;
302 	struct samsung_keypad *keypad;
303 	struct resource *res;
304 	struct input_dev *input_dev;
305 	unsigned int row_shift;
306 	int error;
307 
308 	pdata = dev_get_platdata(&pdev->dev);
309 	if (!pdata) {
310 		pdata = samsung_keypad_parse_dt(&pdev->dev);
311 		if (IS_ERR(pdata))
312 			return PTR_ERR(pdata);
313 	}
314 
315 	keymap_data = pdata->keymap_data;
316 	if (!keymap_data) {
317 		dev_err(&pdev->dev, "no keymap data defined\n");
318 		return -EINVAL;
319 	}
320 
321 	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
322 		return -EINVAL;
323 
324 	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
325 		return -EINVAL;
326 
327 	/* initialize the gpio */
328 	if (pdata->cfg_gpio)
329 		pdata->cfg_gpio(pdata->rows, pdata->cols);
330 
331 	row_shift = get_count_order(pdata->cols);
332 
333 	keypad = devm_kzalloc(&pdev->dev,
334 			      struct_size(keypad, keycodes,
335 					  pdata->rows << row_shift),
336 			      GFP_KERNEL);
337 	if (!keypad)
338 		return -ENOMEM;
339 
340 	input_dev = devm_input_allocate_device(&pdev->dev);
341 	if (!input_dev)
342 		return -ENOMEM;
343 
344 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
345 	if (!res)
346 		return -ENODEV;
347 
348 	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
349 	if (!keypad->base)
350 		return -EBUSY;
351 
352 	keypad->clk = devm_clk_get_prepared(&pdev->dev, "keypad");
353 	if (IS_ERR(keypad->clk)) {
354 		dev_err(&pdev->dev, "failed to get keypad clk\n");
355 		return PTR_ERR(keypad->clk);
356 	}
357 
358 	keypad->input_dev = input_dev;
359 	keypad->pdev = pdev;
360 	keypad->row_shift = row_shift;
361 	keypad->rows = pdata->rows;
362 	keypad->cols = pdata->cols;
363 	keypad->stopped = true;
364 	init_waitqueue_head(&keypad->wait);
365 
366 	keypad->chip = device_get_match_data(&pdev->dev);
367 	if (!keypad->chip) {
368 		id = platform_get_device_id(pdev);
369 		if (id)
370 			keypad->chip = (const void *)id->driver_data;
371 	}
372 
373 	if (!keypad->chip) {
374 		dev_err(&pdev->dev, "Unable to determine chip type");
375 		return -EINVAL;
376 	}
377 
378 	input_dev->name = pdev->name;
379 	input_dev->id.bustype = BUS_HOST;
380 
381 	input_dev->open = samsung_keypad_open;
382 	input_dev->close = samsung_keypad_close;
383 
384 	error = matrix_keypad_build_keymap(keymap_data, NULL,
385 					   pdata->rows, pdata->cols,
386 					   keypad->keycodes, input_dev);
387 	if (error) {
388 		dev_err(&pdev->dev, "failed to build keymap\n");
389 		return error;
390 	}
391 
392 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
393 	if (!pdata->no_autorepeat)
394 		__set_bit(EV_REP, input_dev->evbit);
395 
396 	input_set_drvdata(input_dev, keypad);
397 
398 	keypad->irq = platform_get_irq(pdev, 0);
399 	if (keypad->irq < 0) {
400 		error = keypad->irq;
401 		return error;
402 	}
403 
404 	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
405 					  samsung_keypad_irq,
406 					  IRQF_ONESHOT | IRQF_NO_AUTOEN,
407 					  dev_name(&pdev->dev), keypad);
408 	if (error) {
409 		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
410 		return error;
411 	}
412 
413 	device_init_wakeup(&pdev->dev, pdata->wakeup);
414 	platform_set_drvdata(pdev, keypad);
415 
416 	error = devm_pm_runtime_enable(&pdev->dev);
417 	if (error)
418 		return error;
419 
420 	error = input_register_device(keypad->input_dev);
421 	if (error)
422 		return error;
423 
424 	if (pdev->dev.of_node) {
425 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data->keymap);
426 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data);
427 		devm_kfree(&pdev->dev, (void *)pdata);
428 	}
429 	return 0;
430 }
431 
432 static int samsung_keypad_runtime_suspend(struct device *dev)
433 {
434 	struct platform_device *pdev = to_platform_device(dev);
435 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
436 	unsigned int val;
437 	int error;
438 
439 	if (keypad->stopped)
440 		return 0;
441 
442 	/* This may fail on some SoCs due to lack of controller support */
443 	error = enable_irq_wake(keypad->irq);
444 	if (!error)
445 		keypad->wake_enabled = true;
446 
447 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
448 	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
449 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
450 
451 	clk_disable(keypad->clk);
452 
453 	return 0;
454 }
455 
456 static int samsung_keypad_runtime_resume(struct device *dev)
457 {
458 	struct platform_device *pdev = to_platform_device(dev);
459 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
460 	unsigned int val;
461 
462 	if (keypad->stopped)
463 		return 0;
464 
465 	clk_enable(keypad->clk);
466 
467 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
468 	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
469 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
470 
471 	if (keypad->wake_enabled)
472 		disable_irq_wake(keypad->irq);
473 
474 	return 0;
475 }
476 
477 static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
478 					 bool enable)
479 {
480 	unsigned int val;
481 
482 	clk_enable(keypad->clk);
483 
484 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
485 	if (enable) {
486 		enable_irq_wake(keypad->irq);
487 		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
488 		writel(val, keypad->base + SAMSUNG_KEYIFCON);
489 	} else {
490 		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
491 		writel(val, keypad->base + SAMSUNG_KEYIFCON);
492 		disable_irq_wake(keypad->irq);
493 
494 		if (!input_device_enabled(keypad->input_dev))
495 			writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
496 	}
497 
498 	clk_disable(keypad->clk);
499 }
500 
501 static int samsung_keypad_suspend(struct device *dev)
502 {
503 	struct platform_device *pdev = to_platform_device(dev);
504 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
505 	struct input_dev *input_dev = keypad->input_dev;
506 
507 	guard(mutex)(&input_dev->mutex);
508 
509 	if (input_device_enabled(input_dev))
510 		samsung_keypad_stop(keypad);
511 
512 	if (device_may_wakeup(dev))
513 		samsung_keypad_toggle_wakeup(keypad, true);
514 
515 	return 0;
516 }
517 
518 static int samsung_keypad_resume(struct device *dev)
519 {
520 	struct platform_device *pdev = to_platform_device(dev);
521 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
522 	struct input_dev *input_dev = keypad->input_dev;
523 
524 	guard(mutex)(&input_dev->mutex);
525 
526 	if (device_may_wakeup(dev))
527 		samsung_keypad_toggle_wakeup(keypad, false);
528 
529 	if (input_device_enabled(input_dev))
530 		samsung_keypad_start(keypad);
531 
532 	return 0;
533 }
534 
535 static const struct dev_pm_ops samsung_keypad_pm_ops = {
536 	SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
537 	RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
538 		       samsung_keypad_runtime_resume, NULL)
539 };
540 
541 static const struct samsung_chip_info samsung_s3c6410_chip_info = {
542 	.column_shift = 0,
543 };
544 
545 static const struct samsung_chip_info samsung_s5pv210_chip_info = {
546 	.column_shift = 8,
547 };
548 
549 #ifdef CONFIG_OF
550 static const struct of_device_id samsung_keypad_dt_match[] = {
551 	{
552 		.compatible = "samsung,s3c6410-keypad",
553 		.data = &samsung_s3c6410_chip_info,
554 	}, {
555 		.compatible = "samsung,s5pv210-keypad",
556 		.data = &samsung_s5pv210_chip_info,
557 	},
558 	{ }
559 };
560 MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
561 #endif
562 
563 static const struct platform_device_id samsung_keypad_driver_ids[] = {
564 	{
565 		.name		= "samsung-keypad",
566 		.driver_data	= (kernel_ulong_t)&samsung_s3c6410_chip_info,
567 	}, {
568 		.name		= "s5pv210-keypad",
569 		.driver_data	= (kernel_ulong_t)&samsung_s5pv210_chip_info,
570 	},
571 	{ }
572 };
573 MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
574 
575 static struct platform_driver samsung_keypad_driver = {
576 	.probe		= samsung_keypad_probe,
577 	.driver		= {
578 		.name	= "samsung-keypad",
579 		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
580 		.pm	= pm_ptr(&samsung_keypad_pm_ops),
581 	},
582 	.id_table	= samsung_keypad_driver_ids,
583 };
584 module_platform_driver(samsung_keypad_driver);
585 
586 MODULE_DESCRIPTION("Samsung keypad driver");
587 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
588 MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
589 MODULE_LICENSE("GPL");
590