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 	unsigned int val;
150 	bool key_down;
151 
152 	pm_runtime_get_sync(&keypad->pdev->dev);
153 
154 	do {
155 		val = readl(keypad->base + SAMSUNG_KEYIFSTSCLR);
156 		/* Clear interrupt. */
157 		writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
158 
159 		samsung_keypad_scan(keypad, row_state);
160 
161 		key_down = samsung_keypad_report(keypad, row_state);
162 		if (key_down)
163 			wait_event_timeout(keypad->wait, keypad->stopped,
164 					   msecs_to_jiffies(50));
165 
166 	} while (key_down && !keypad->stopped);
167 
168 	pm_runtime_put(&keypad->pdev->dev);
169 
170 	return IRQ_HANDLED;
171 }
172 
173 static void samsung_keypad_start(struct samsung_keypad *keypad)
174 {
175 	unsigned int val;
176 
177 	pm_runtime_get_sync(&keypad->pdev->dev);
178 
179 	/* Tell IRQ thread that it may poll the device. */
180 	keypad->stopped = false;
181 
182 	clk_enable(keypad->clk);
183 
184 	/* Enable interrupt bits. */
185 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
186 	val |= SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN;
187 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
188 
189 	/* KEYIFCOL reg clear. */
190 	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
191 
192 	pm_runtime_put(&keypad->pdev->dev);
193 }
194 
195 static void samsung_keypad_stop(struct samsung_keypad *keypad)
196 {
197 	unsigned int val;
198 
199 	pm_runtime_get_sync(&keypad->pdev->dev);
200 
201 	/* Signal IRQ thread to stop polling and disable the handler. */
202 	keypad->stopped = true;
203 	wake_up(&keypad->wait);
204 	disable_irq(keypad->irq);
205 
206 	/* Clear interrupt. */
207 	writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
208 
209 	/* Disable interrupt bits. */
210 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
211 	val &= ~(SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN);
212 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
213 
214 	clk_disable(keypad->clk);
215 
216 	/*
217 	 * Now that chip should not generate interrupts we can safely
218 	 * re-enable the handler.
219 	 */
220 	enable_irq(keypad->irq);
221 
222 	pm_runtime_put(&keypad->pdev->dev);
223 }
224 
225 static int samsung_keypad_open(struct input_dev *input_dev)
226 {
227 	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
228 
229 	samsung_keypad_start(keypad);
230 
231 	return 0;
232 }
233 
234 static void samsung_keypad_close(struct input_dev *input_dev)
235 {
236 	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
237 
238 	samsung_keypad_stop(keypad);
239 }
240 
241 #ifdef CONFIG_OF
242 static struct samsung_keypad_platdata *
243 samsung_keypad_parse_dt(struct device *dev)
244 {
245 	struct samsung_keypad_platdata *pdata;
246 	struct matrix_keymap_data *keymap_data;
247 	uint32_t *keymap, num_rows = 0, num_cols = 0;
248 	struct device_node *np = dev->of_node, *key_np;
249 	unsigned int key_count;
250 
251 	if (!np) {
252 		dev_err(dev, "missing device tree data\n");
253 		return ERR_PTR(-EINVAL);
254 	}
255 
256 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
257 	if (!pdata) {
258 		dev_err(dev, "could not allocate memory for platform data\n");
259 		return ERR_PTR(-ENOMEM);
260 	}
261 
262 	of_property_read_u32(np, "samsung,keypad-num-rows", &num_rows);
263 	of_property_read_u32(np, "samsung,keypad-num-columns", &num_cols);
264 	if (!num_rows || !num_cols) {
265 		dev_err(dev, "number of keypad rows/columns not specified\n");
266 		return ERR_PTR(-EINVAL);
267 	}
268 	pdata->rows = num_rows;
269 	pdata->cols = num_cols;
270 
271 	keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
272 	if (!keymap_data) {
273 		dev_err(dev, "could not allocate memory for keymap data\n");
274 		return ERR_PTR(-ENOMEM);
275 	}
276 	pdata->keymap_data = keymap_data;
277 
278 	key_count = of_get_child_count(np);
279 	keymap_data->keymap_size = key_count;
280 	keymap = devm_kcalloc(dev, key_count, sizeof(uint32_t), GFP_KERNEL);
281 	if (!keymap) {
282 		dev_err(dev, "could not allocate memory for keymap\n");
283 		return ERR_PTR(-ENOMEM);
284 	}
285 	keymap_data->keymap = keymap;
286 
287 	for_each_child_of_node(np, key_np) {
288 		u32 row, col, key_code;
289 		of_property_read_u32(key_np, "keypad,row", &row);
290 		of_property_read_u32(key_np, "keypad,column", &col);
291 		of_property_read_u32(key_np, "linux,code", &key_code);
292 		*keymap++ = KEY(row, col, key_code);
293 	}
294 
295 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
296 		pdata->no_autorepeat = true;
297 
298 	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
299 			/* legacy name */
300 			of_property_read_bool(np, "linux,input-wakeup");
301 
302 
303 	return pdata;
304 }
305 #else
306 static struct samsung_keypad_platdata *
307 samsung_keypad_parse_dt(struct device *dev)
308 {
309 	dev_err(dev, "no platform data defined\n");
310 
311 	return ERR_PTR(-EINVAL);
312 }
313 #endif
314 
315 static int samsung_keypad_probe(struct platform_device *pdev)
316 {
317 	const struct samsung_keypad_platdata *pdata;
318 	const struct matrix_keymap_data *keymap_data;
319 	struct samsung_keypad *keypad;
320 	struct resource *res;
321 	struct input_dev *input_dev;
322 	unsigned int row_shift;
323 	unsigned int keymap_size;
324 	int error;
325 
326 	pdata = dev_get_platdata(&pdev->dev);
327 	if (!pdata) {
328 		pdata = samsung_keypad_parse_dt(&pdev->dev);
329 		if (IS_ERR(pdata))
330 			return PTR_ERR(pdata);
331 	}
332 
333 	keymap_data = pdata->keymap_data;
334 	if (!keymap_data) {
335 		dev_err(&pdev->dev, "no keymap data defined\n");
336 		return -EINVAL;
337 	}
338 
339 	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
340 		return -EINVAL;
341 
342 	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
343 		return -EINVAL;
344 
345 	/* initialize the gpio */
346 	if (pdata->cfg_gpio)
347 		pdata->cfg_gpio(pdata->rows, pdata->cols);
348 
349 	row_shift = get_count_order(pdata->cols);
350 	keymap_size = (pdata->rows << row_shift) * sizeof(keypad->keycodes[0]);
351 
352 	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad) + keymap_size,
353 			      GFP_KERNEL);
354 	input_dev = devm_input_allocate_device(&pdev->dev);
355 	if (!keypad || !input_dev)
356 		return -ENOMEM;
357 
358 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
359 	if (!res)
360 		return -ENODEV;
361 
362 	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
363 	if (!keypad->base)
364 		return -EBUSY;
365 
366 	keypad->clk = devm_clk_get(&pdev->dev, "keypad");
367 	if (IS_ERR(keypad->clk)) {
368 		dev_err(&pdev->dev, "failed to get keypad clk\n");
369 		return PTR_ERR(keypad->clk);
370 	}
371 
372 	error = clk_prepare(keypad->clk);
373 	if (error) {
374 		dev_err(&pdev->dev, "keypad clock prepare failed\n");
375 		return error;
376 	}
377 
378 	keypad->input_dev = input_dev;
379 	keypad->pdev = pdev;
380 	keypad->row_shift = row_shift;
381 	keypad->rows = pdata->rows;
382 	keypad->cols = pdata->cols;
383 	keypad->stopped = true;
384 	init_waitqueue_head(&keypad->wait);
385 
386 	if (pdev->dev.of_node)
387 		keypad->type = of_device_is_compatible(pdev->dev.of_node,
388 					"samsung,s5pv210-keypad");
389 	else
390 		keypad->type = platform_get_device_id(pdev)->driver_data;
391 
392 	input_dev->name = pdev->name;
393 	input_dev->id.bustype = BUS_HOST;
394 	input_dev->dev.parent = &pdev->dev;
395 
396 	input_dev->open = samsung_keypad_open;
397 	input_dev->close = samsung_keypad_close;
398 
399 	error = matrix_keypad_build_keymap(keymap_data, NULL,
400 					   pdata->rows, pdata->cols,
401 					   keypad->keycodes, input_dev);
402 	if (error) {
403 		dev_err(&pdev->dev, "failed to build keymap\n");
404 		goto err_unprepare_clk;
405 	}
406 
407 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
408 	if (!pdata->no_autorepeat)
409 		__set_bit(EV_REP, input_dev->evbit);
410 
411 	input_set_drvdata(input_dev, keypad);
412 
413 	keypad->irq = platform_get_irq(pdev, 0);
414 	if (keypad->irq < 0) {
415 		error = keypad->irq;
416 		goto err_unprepare_clk;
417 	}
418 
419 	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
420 					  samsung_keypad_irq, IRQF_ONESHOT,
421 					  dev_name(&pdev->dev), keypad);
422 	if (error) {
423 		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
424 		goto err_unprepare_clk;
425 	}
426 
427 	device_init_wakeup(&pdev->dev, pdata->wakeup);
428 	platform_set_drvdata(pdev, keypad);
429 	pm_runtime_enable(&pdev->dev);
430 
431 	error = input_register_device(keypad->input_dev);
432 	if (error)
433 		goto err_disable_runtime_pm;
434 
435 	if (pdev->dev.of_node) {
436 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data->keymap);
437 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data);
438 		devm_kfree(&pdev->dev, (void *)pdata);
439 	}
440 	return 0;
441 
442 err_disable_runtime_pm:
443 	pm_runtime_disable(&pdev->dev);
444 err_unprepare_clk:
445 	clk_unprepare(keypad->clk);
446 	return error;
447 }
448 
449 static int samsung_keypad_remove(struct platform_device *pdev)
450 {
451 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
452 
453 	pm_runtime_disable(&pdev->dev);
454 
455 	input_unregister_device(keypad->input_dev);
456 
457 	clk_unprepare(keypad->clk);
458 
459 	return 0;
460 }
461 
462 #ifdef CONFIG_PM
463 static int samsung_keypad_runtime_suspend(struct device *dev)
464 {
465 	struct platform_device *pdev = to_platform_device(dev);
466 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
467 	unsigned int val;
468 	int error;
469 
470 	if (keypad->stopped)
471 		return 0;
472 
473 	/* This may fail on some SoCs due to lack of controller support */
474 	error = enable_irq_wake(keypad->irq);
475 	if (!error)
476 		keypad->wake_enabled = true;
477 
478 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
479 	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
480 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
481 
482 	clk_disable(keypad->clk);
483 
484 	return 0;
485 }
486 
487 static int samsung_keypad_runtime_resume(struct device *dev)
488 {
489 	struct platform_device *pdev = to_platform_device(dev);
490 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
491 	unsigned int val;
492 
493 	if (keypad->stopped)
494 		return 0;
495 
496 	clk_enable(keypad->clk);
497 
498 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
499 	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
500 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
501 
502 	if (keypad->wake_enabled)
503 		disable_irq_wake(keypad->irq);
504 
505 	return 0;
506 }
507 #endif
508 
509 #ifdef CONFIG_PM_SLEEP
510 static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
511 					 bool enable)
512 {
513 	unsigned int val;
514 
515 	clk_enable(keypad->clk);
516 
517 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
518 	if (enable) {
519 		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
520 		if (device_may_wakeup(&keypad->pdev->dev))
521 			enable_irq_wake(keypad->irq);
522 	} else {
523 		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
524 		if (device_may_wakeup(&keypad->pdev->dev))
525 			disable_irq_wake(keypad->irq);
526 	}
527 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
528 
529 	clk_disable(keypad->clk);
530 }
531 
532 static int samsung_keypad_suspend(struct device *dev)
533 {
534 	struct platform_device *pdev = to_platform_device(dev);
535 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
536 	struct input_dev *input_dev = keypad->input_dev;
537 
538 	mutex_lock(&input_dev->mutex);
539 
540 	if (input_dev->users)
541 		samsung_keypad_stop(keypad);
542 
543 	samsung_keypad_toggle_wakeup(keypad, true);
544 
545 	mutex_unlock(&input_dev->mutex);
546 
547 	return 0;
548 }
549 
550 static int samsung_keypad_resume(struct device *dev)
551 {
552 	struct platform_device *pdev = to_platform_device(dev);
553 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
554 	struct input_dev *input_dev = keypad->input_dev;
555 
556 	mutex_lock(&input_dev->mutex);
557 
558 	samsung_keypad_toggle_wakeup(keypad, false);
559 
560 	if (input_dev->users)
561 		samsung_keypad_start(keypad);
562 
563 	mutex_unlock(&input_dev->mutex);
564 
565 	return 0;
566 }
567 #endif
568 
569 static const struct dev_pm_ops samsung_keypad_pm_ops = {
570 	SET_SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
571 	SET_RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
572 			   samsung_keypad_runtime_resume, NULL)
573 };
574 
575 #ifdef CONFIG_OF
576 static const struct of_device_id samsung_keypad_dt_match[] = {
577 	{ .compatible = "samsung,s3c6410-keypad" },
578 	{ .compatible = "samsung,s5pv210-keypad" },
579 	{},
580 };
581 MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
582 #endif
583 
584 static const struct platform_device_id samsung_keypad_driver_ids[] = {
585 	{
586 		.name		= "samsung-keypad",
587 		.driver_data	= KEYPAD_TYPE_SAMSUNG,
588 	}, {
589 		.name		= "s5pv210-keypad",
590 		.driver_data	= KEYPAD_TYPE_S5PV210,
591 	},
592 	{ },
593 };
594 MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
595 
596 static struct platform_driver samsung_keypad_driver = {
597 	.probe		= samsung_keypad_probe,
598 	.remove		= samsung_keypad_remove,
599 	.driver		= {
600 		.name	= "samsung-keypad",
601 		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
602 		.pm	= &samsung_keypad_pm_ops,
603 	},
604 	.id_table	= samsung_keypad_driver_ids,
605 };
606 module_platform_driver(samsung_keypad_driver);
607 
608 MODULE_DESCRIPTION("Samsung keypad driver");
609 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
610 MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
611 MODULE_LICENSE("GPL");
612