1 /*
2  * Samsung keypad driver
3  *
4  * Copyright (C) 2010 Samsung Electronics Co.Ltd
5  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
6  * Author: Donghwa Lee <dh09.lee@samsung.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/input.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/slab.h>
25 #include <linux/of.h>
26 #include <linux/sched.h>
27 #include <linux/input/samsung-keypad.h>
28 
29 #define SAMSUNG_KEYIFCON			0x00
30 #define SAMSUNG_KEYIFSTSCLR			0x04
31 #define SAMSUNG_KEYIFCOL			0x08
32 #define SAMSUNG_KEYIFROW			0x0c
33 #define SAMSUNG_KEYIFFC				0x10
34 
35 /* SAMSUNG_KEYIFCON */
36 #define SAMSUNG_KEYIFCON_INT_F_EN		(1 << 0)
37 #define SAMSUNG_KEYIFCON_INT_R_EN		(1 << 1)
38 #define SAMSUNG_KEYIFCON_DF_EN			(1 << 2)
39 #define SAMSUNG_KEYIFCON_FC_EN			(1 << 3)
40 #define SAMSUNG_KEYIFCON_WAKEUPEN		(1 << 4)
41 
42 /* SAMSUNG_KEYIFSTSCLR */
43 #define SAMSUNG_KEYIFSTSCLR_P_INT_MASK		(0xff << 0)
44 #define SAMSUNG_KEYIFSTSCLR_R_INT_MASK		(0xff << 8)
45 #define SAMSUNG_KEYIFSTSCLR_R_INT_OFFSET	8
46 #define S5PV210_KEYIFSTSCLR_P_INT_MASK		(0x3fff << 0)
47 #define S5PV210_KEYIFSTSCLR_R_INT_MASK		(0x3fff << 16)
48 #define S5PV210_KEYIFSTSCLR_R_INT_OFFSET	16
49 
50 /* SAMSUNG_KEYIFCOL */
51 #define SAMSUNG_KEYIFCOL_MASK			(0xff << 0)
52 #define S5PV210_KEYIFCOLEN_MASK			(0xff << 8)
53 
54 /* SAMSUNG_KEYIFROW */
55 #define SAMSUNG_KEYIFROW_MASK			(0xff << 0)
56 #define S5PV210_KEYIFROW_MASK			(0x3fff << 0)
57 
58 /* SAMSUNG_KEYIFFC */
59 #define SAMSUNG_KEYIFFC_MASK			(0x3ff << 0)
60 
61 enum samsung_keypad_type {
62 	KEYPAD_TYPE_SAMSUNG,
63 	KEYPAD_TYPE_S5PV210,
64 };
65 
66 struct samsung_keypad {
67 	struct input_dev *input_dev;
68 	struct platform_device *pdev;
69 	struct clk *clk;
70 	void __iomem *base;
71 	wait_queue_head_t wait;
72 	bool stopped;
73 	bool wake_enabled;
74 	int irq;
75 	enum samsung_keypad_type type;
76 	unsigned int row_shift;
77 	unsigned int rows;
78 	unsigned int cols;
79 	unsigned int row_state[SAMSUNG_MAX_COLS];
80 	unsigned short keycodes[];
81 };
82 
83 static void samsung_keypad_scan(struct samsung_keypad *keypad,
84 				unsigned int *row_state)
85 {
86 	unsigned int col;
87 	unsigned int val;
88 
89 	for (col = 0; col < keypad->cols; col++) {
90 		if (keypad->type == KEYPAD_TYPE_S5PV210) {
91 			val = S5PV210_KEYIFCOLEN_MASK;
92 			val &= ~(1 << col) << 8;
93 		} else {
94 			val = SAMSUNG_KEYIFCOL_MASK;
95 			val &= ~(1 << col);
96 		}
97 
98 		writel(val, keypad->base + SAMSUNG_KEYIFCOL);
99 		mdelay(1);
100 
101 		val = readl(keypad->base + SAMSUNG_KEYIFROW);
102 		row_state[col] = ~val & ((1 << keypad->rows) - 1);
103 	}
104 
105 	/* KEYIFCOL reg clear */
106 	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
107 }
108 
109 static bool samsung_keypad_report(struct samsung_keypad *keypad,
110 				  unsigned int *row_state)
111 {
112 	struct input_dev *input_dev = keypad->input_dev;
113 	unsigned int changed;
114 	unsigned int pressed;
115 	unsigned int key_down = 0;
116 	unsigned int val;
117 	unsigned int col, row;
118 
119 	for (col = 0; col < keypad->cols; col++) {
120 		changed = row_state[col] ^ keypad->row_state[col];
121 		key_down |= row_state[col];
122 		if (!changed)
123 			continue;
124 
125 		for (row = 0; row < keypad->rows; row++) {
126 			if (!(changed & (1 << row)))
127 				continue;
128 
129 			pressed = row_state[col] & (1 << row);
130 
131 			dev_dbg(&keypad->input_dev->dev,
132 				"key %s, row: %d, col: %d\n",
133 				pressed ? "pressed" : "released", row, col);
134 
135 			val = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
136 
137 			input_event(input_dev, EV_MSC, MSC_SCAN, val);
138 			input_report_key(input_dev,
139 					keypad->keycodes[val], pressed);
140 		}
141 		input_sync(keypad->input_dev);
142 	}
143 
144 	memcpy(keypad->row_state, row_state, sizeof(keypad->row_state));
145 
146 	return key_down;
147 }
148 
149 static irqreturn_t samsung_keypad_irq(int irq, void *dev_id)
150 {
151 	struct samsung_keypad *keypad = dev_id;
152 	unsigned int row_state[SAMSUNG_MAX_COLS];
153 	unsigned int val;
154 	bool key_down;
155 
156 	pm_runtime_get_sync(&keypad->pdev->dev);
157 
158 	do {
159 		val = readl(keypad->base + SAMSUNG_KEYIFSTSCLR);
160 		/* Clear interrupt. */
161 		writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
162 
163 		samsung_keypad_scan(keypad, row_state);
164 
165 		key_down = samsung_keypad_report(keypad, row_state);
166 		if (key_down)
167 			wait_event_timeout(keypad->wait, keypad->stopped,
168 					   msecs_to_jiffies(50));
169 
170 	} while (key_down && !keypad->stopped);
171 
172 	pm_runtime_put(&keypad->pdev->dev);
173 
174 	return IRQ_HANDLED;
175 }
176 
177 static void samsung_keypad_start(struct samsung_keypad *keypad)
178 {
179 	unsigned int val;
180 
181 	pm_runtime_get_sync(&keypad->pdev->dev);
182 
183 	/* Tell IRQ thread that it may poll the device. */
184 	keypad->stopped = false;
185 
186 	clk_enable(keypad->clk);
187 
188 	/* Enable interrupt bits. */
189 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
190 	val |= SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN;
191 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
192 
193 	/* KEYIFCOL reg clear. */
194 	writel(0, keypad->base + SAMSUNG_KEYIFCOL);
195 
196 	pm_runtime_put(&keypad->pdev->dev);
197 }
198 
199 static void samsung_keypad_stop(struct samsung_keypad *keypad)
200 {
201 	unsigned int val;
202 
203 	pm_runtime_get_sync(&keypad->pdev->dev);
204 
205 	/* Signal IRQ thread to stop polling and disable the handler. */
206 	keypad->stopped = true;
207 	wake_up(&keypad->wait);
208 	disable_irq(keypad->irq);
209 
210 	/* Clear interrupt. */
211 	writel(~0x0, keypad->base + SAMSUNG_KEYIFSTSCLR);
212 
213 	/* Disable interrupt bits. */
214 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
215 	val &= ~(SAMSUNG_KEYIFCON_INT_F_EN | SAMSUNG_KEYIFCON_INT_R_EN);
216 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
217 
218 	clk_disable(keypad->clk);
219 
220 	/*
221 	 * Now that chip should not generate interrupts we can safely
222 	 * re-enable the handler.
223 	 */
224 	enable_irq(keypad->irq);
225 
226 	pm_runtime_put(&keypad->pdev->dev);
227 }
228 
229 static int samsung_keypad_open(struct input_dev *input_dev)
230 {
231 	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
232 
233 	samsung_keypad_start(keypad);
234 
235 	return 0;
236 }
237 
238 static void samsung_keypad_close(struct input_dev *input_dev)
239 {
240 	struct samsung_keypad *keypad = input_get_drvdata(input_dev);
241 
242 	samsung_keypad_stop(keypad);
243 }
244 
245 #ifdef CONFIG_OF
246 static struct samsung_keypad_platdata *
247 samsung_keypad_parse_dt(struct device *dev)
248 {
249 	struct samsung_keypad_platdata *pdata;
250 	struct matrix_keymap_data *keymap_data;
251 	uint32_t *keymap, num_rows = 0, num_cols = 0;
252 	struct device_node *np = dev->of_node, *key_np;
253 	unsigned int key_count;
254 
255 	if (!np) {
256 		dev_err(dev, "missing device tree data\n");
257 		return ERR_PTR(-EINVAL);
258 	}
259 
260 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
261 	if (!pdata) {
262 		dev_err(dev, "could not allocate memory for platform data\n");
263 		return ERR_PTR(-ENOMEM);
264 	}
265 
266 	of_property_read_u32(np, "samsung,keypad-num-rows", &num_rows);
267 	of_property_read_u32(np, "samsung,keypad-num-columns", &num_cols);
268 	if (!num_rows || !num_cols) {
269 		dev_err(dev, "number of keypad rows/columns not specified\n");
270 		return ERR_PTR(-EINVAL);
271 	}
272 	pdata->rows = num_rows;
273 	pdata->cols = num_cols;
274 
275 	keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
276 	if (!keymap_data) {
277 		dev_err(dev, "could not allocate memory for keymap data\n");
278 		return ERR_PTR(-ENOMEM);
279 	}
280 	pdata->keymap_data = keymap_data;
281 
282 	key_count = of_get_child_count(np);
283 	keymap_data->keymap_size = key_count;
284 	keymap = devm_kzalloc(dev, sizeof(uint32_t) * key_count, GFP_KERNEL);
285 	if (!keymap) {
286 		dev_err(dev, "could not allocate memory for keymap\n");
287 		return ERR_PTR(-ENOMEM);
288 	}
289 	keymap_data->keymap = keymap;
290 
291 	for_each_child_of_node(np, key_np) {
292 		u32 row, col, key_code;
293 		of_property_read_u32(key_np, "keypad,row", &row);
294 		of_property_read_u32(key_np, "keypad,column", &col);
295 		of_property_read_u32(key_np, "linux,code", &key_code);
296 		*keymap++ = KEY(row, col, key_code);
297 	}
298 
299 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
300 		pdata->no_autorepeat = true;
301 
302 	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
303 			/* legacy name */
304 			of_property_read_bool(np, "linux,input-wakeup");
305 
306 
307 	return pdata;
308 }
309 #else
310 static struct samsung_keypad_platdata *
311 samsung_keypad_parse_dt(struct device *dev)
312 {
313 	dev_err(dev, "no platform data defined\n");
314 
315 	return ERR_PTR(-EINVAL);
316 }
317 #endif
318 
319 static int samsung_keypad_probe(struct platform_device *pdev)
320 {
321 	const struct samsung_keypad_platdata *pdata;
322 	const struct matrix_keymap_data *keymap_data;
323 	struct samsung_keypad *keypad;
324 	struct resource *res;
325 	struct input_dev *input_dev;
326 	unsigned int row_shift;
327 	unsigned int keymap_size;
328 	int error;
329 
330 	pdata = dev_get_platdata(&pdev->dev);
331 	if (!pdata) {
332 		pdata = samsung_keypad_parse_dt(&pdev->dev);
333 		if (IS_ERR(pdata))
334 			return PTR_ERR(pdata);
335 	}
336 
337 	keymap_data = pdata->keymap_data;
338 	if (!keymap_data) {
339 		dev_err(&pdev->dev, "no keymap data defined\n");
340 		return -EINVAL;
341 	}
342 
343 	if (!pdata->rows || pdata->rows > SAMSUNG_MAX_ROWS)
344 		return -EINVAL;
345 
346 	if (!pdata->cols || pdata->cols > SAMSUNG_MAX_COLS)
347 		return -EINVAL;
348 
349 	/* initialize the gpio */
350 	if (pdata->cfg_gpio)
351 		pdata->cfg_gpio(pdata->rows, pdata->cols);
352 
353 	row_shift = get_count_order(pdata->cols);
354 	keymap_size = (pdata->rows << row_shift) * sizeof(keypad->keycodes[0]);
355 
356 	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad) + keymap_size,
357 			      GFP_KERNEL);
358 	input_dev = devm_input_allocate_device(&pdev->dev);
359 	if (!keypad || !input_dev)
360 		return -ENOMEM;
361 
362 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
363 	if (!res)
364 		return -ENODEV;
365 
366 	keypad->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
367 	if (!keypad->base)
368 		return -EBUSY;
369 
370 	keypad->clk = devm_clk_get(&pdev->dev, "keypad");
371 	if (IS_ERR(keypad->clk)) {
372 		dev_err(&pdev->dev, "failed to get keypad clk\n");
373 		return PTR_ERR(keypad->clk);
374 	}
375 
376 	error = clk_prepare(keypad->clk);
377 	if (error) {
378 		dev_err(&pdev->dev, "keypad clock prepare failed\n");
379 		return error;
380 	}
381 
382 	keypad->input_dev = input_dev;
383 	keypad->pdev = pdev;
384 	keypad->row_shift = row_shift;
385 	keypad->rows = pdata->rows;
386 	keypad->cols = pdata->cols;
387 	keypad->stopped = true;
388 	init_waitqueue_head(&keypad->wait);
389 
390 	if (pdev->dev.of_node)
391 		keypad->type = of_device_is_compatible(pdev->dev.of_node,
392 					"samsung,s5pv210-keypad");
393 	else
394 		keypad->type = platform_get_device_id(pdev)->driver_data;
395 
396 	input_dev->name = pdev->name;
397 	input_dev->id.bustype = BUS_HOST;
398 	input_dev->dev.parent = &pdev->dev;
399 
400 	input_dev->open = samsung_keypad_open;
401 	input_dev->close = samsung_keypad_close;
402 
403 	error = matrix_keypad_build_keymap(keymap_data, NULL,
404 					   pdata->rows, pdata->cols,
405 					   keypad->keycodes, input_dev);
406 	if (error) {
407 		dev_err(&pdev->dev, "failed to build keymap\n");
408 		goto err_unprepare_clk;
409 	}
410 
411 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
412 	if (!pdata->no_autorepeat)
413 		__set_bit(EV_REP, input_dev->evbit);
414 
415 	input_set_drvdata(input_dev, keypad);
416 
417 	keypad->irq = platform_get_irq(pdev, 0);
418 	if (keypad->irq < 0) {
419 		error = keypad->irq;
420 		goto err_unprepare_clk;
421 	}
422 
423 	error = devm_request_threaded_irq(&pdev->dev, keypad->irq, NULL,
424 					  samsung_keypad_irq, IRQF_ONESHOT,
425 					  dev_name(&pdev->dev), keypad);
426 	if (error) {
427 		dev_err(&pdev->dev, "failed to register keypad interrupt\n");
428 		goto err_unprepare_clk;
429 	}
430 
431 	device_init_wakeup(&pdev->dev, pdata->wakeup);
432 	platform_set_drvdata(pdev, keypad);
433 	pm_runtime_enable(&pdev->dev);
434 
435 	error = input_register_device(keypad->input_dev);
436 	if (error)
437 		goto err_disable_runtime_pm;
438 
439 	if (pdev->dev.of_node) {
440 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data->keymap);
441 		devm_kfree(&pdev->dev, (void *)pdata->keymap_data);
442 		devm_kfree(&pdev->dev, (void *)pdata);
443 	}
444 	return 0;
445 
446 err_disable_runtime_pm:
447 	pm_runtime_disable(&pdev->dev);
448 err_unprepare_clk:
449 	clk_unprepare(keypad->clk);
450 	return error;
451 }
452 
453 static int samsung_keypad_remove(struct platform_device *pdev)
454 {
455 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
456 
457 	pm_runtime_disable(&pdev->dev);
458 
459 	input_unregister_device(keypad->input_dev);
460 
461 	clk_unprepare(keypad->clk);
462 
463 	return 0;
464 }
465 
466 #ifdef CONFIG_PM
467 static int samsung_keypad_runtime_suspend(struct device *dev)
468 {
469 	struct platform_device *pdev = to_platform_device(dev);
470 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
471 	unsigned int val;
472 	int error;
473 
474 	if (keypad->stopped)
475 		return 0;
476 
477 	/* This may fail on some SoCs due to lack of controller support */
478 	error = enable_irq_wake(keypad->irq);
479 	if (!error)
480 		keypad->wake_enabled = true;
481 
482 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
483 	val |= SAMSUNG_KEYIFCON_WAKEUPEN;
484 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
485 
486 	clk_disable(keypad->clk);
487 
488 	return 0;
489 }
490 
491 static int samsung_keypad_runtime_resume(struct device *dev)
492 {
493 	struct platform_device *pdev = to_platform_device(dev);
494 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
495 	unsigned int val;
496 
497 	if (keypad->stopped)
498 		return 0;
499 
500 	clk_enable(keypad->clk);
501 
502 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
503 	val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
504 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
505 
506 	if (keypad->wake_enabled)
507 		disable_irq_wake(keypad->irq);
508 
509 	return 0;
510 }
511 #endif
512 
513 #ifdef CONFIG_PM_SLEEP
514 static void samsung_keypad_toggle_wakeup(struct samsung_keypad *keypad,
515 					 bool enable)
516 {
517 	unsigned int val;
518 
519 	clk_enable(keypad->clk);
520 
521 	val = readl(keypad->base + SAMSUNG_KEYIFCON);
522 	if (enable) {
523 		val |= SAMSUNG_KEYIFCON_WAKEUPEN;
524 		if (device_may_wakeup(&keypad->pdev->dev))
525 			enable_irq_wake(keypad->irq);
526 	} else {
527 		val &= ~SAMSUNG_KEYIFCON_WAKEUPEN;
528 		if (device_may_wakeup(&keypad->pdev->dev))
529 			disable_irq_wake(keypad->irq);
530 	}
531 	writel(val, keypad->base + SAMSUNG_KEYIFCON);
532 
533 	clk_disable(keypad->clk);
534 }
535 
536 static int samsung_keypad_suspend(struct device *dev)
537 {
538 	struct platform_device *pdev = to_platform_device(dev);
539 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
540 	struct input_dev *input_dev = keypad->input_dev;
541 
542 	mutex_lock(&input_dev->mutex);
543 
544 	if (input_dev->users)
545 		samsung_keypad_stop(keypad);
546 
547 	samsung_keypad_toggle_wakeup(keypad, true);
548 
549 	mutex_unlock(&input_dev->mutex);
550 
551 	return 0;
552 }
553 
554 static int samsung_keypad_resume(struct device *dev)
555 {
556 	struct platform_device *pdev = to_platform_device(dev);
557 	struct samsung_keypad *keypad = platform_get_drvdata(pdev);
558 	struct input_dev *input_dev = keypad->input_dev;
559 
560 	mutex_lock(&input_dev->mutex);
561 
562 	samsung_keypad_toggle_wakeup(keypad, false);
563 
564 	if (input_dev->users)
565 		samsung_keypad_start(keypad);
566 
567 	mutex_unlock(&input_dev->mutex);
568 
569 	return 0;
570 }
571 #endif
572 
573 static const struct dev_pm_ops samsung_keypad_pm_ops = {
574 	SET_SYSTEM_SLEEP_PM_OPS(samsung_keypad_suspend, samsung_keypad_resume)
575 	SET_RUNTIME_PM_OPS(samsung_keypad_runtime_suspend,
576 			   samsung_keypad_runtime_resume, NULL)
577 };
578 
579 #ifdef CONFIG_OF
580 static const struct of_device_id samsung_keypad_dt_match[] = {
581 	{ .compatible = "samsung,s3c6410-keypad" },
582 	{ .compatible = "samsung,s5pv210-keypad" },
583 	{},
584 };
585 MODULE_DEVICE_TABLE(of, samsung_keypad_dt_match);
586 #endif
587 
588 static const struct platform_device_id samsung_keypad_driver_ids[] = {
589 	{
590 		.name		= "samsung-keypad",
591 		.driver_data	= KEYPAD_TYPE_SAMSUNG,
592 	}, {
593 		.name		= "s5pv210-keypad",
594 		.driver_data	= KEYPAD_TYPE_S5PV210,
595 	},
596 	{ },
597 };
598 MODULE_DEVICE_TABLE(platform, samsung_keypad_driver_ids);
599 
600 static struct platform_driver samsung_keypad_driver = {
601 	.probe		= samsung_keypad_probe,
602 	.remove		= samsung_keypad_remove,
603 	.driver		= {
604 		.name	= "samsung-keypad",
605 		.of_match_table = of_match_ptr(samsung_keypad_dt_match),
606 		.pm	= &samsung_keypad_pm_ops,
607 	},
608 	.id_table	= samsung_keypad_driver_ids,
609 };
610 module_platform_driver(samsung_keypad_driver);
611 
612 MODULE_DESCRIPTION("Samsung keypad driver");
613 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
614 MODULE_AUTHOR("Donghwa Lee <dh09.lee@samsung.com>");
615 MODULE_LICENSE("GPL");
616