1 /*
2  * OMAP4 Keypad Driver
3  *
4  * Copyright (C) 2010 Texas Instruments
5  *
6  * Author: Abraham Arce <x0066660@ti.com>
7  * Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  */
23 
24 #include <linux/module.h>
25 #include <linux/interrupt.h>
26 #include <linux/platform_device.h>
27 #include <linux/errno.h>
28 #include <linux/io.h>
29 #include <linux/of.h>
30 #include <linux/input.h>
31 #include <linux/input/matrix_keypad.h>
32 #include <linux/slab.h>
33 #include <linux/pm_runtime.h>
34 
35 /* OMAP4 registers */
36 #define OMAP4_KBD_REVISION		0x00
37 #define OMAP4_KBD_SYSCONFIG		0x10
38 #define OMAP4_KBD_SYSSTATUS		0x14
39 #define OMAP4_KBD_IRQSTATUS		0x18
40 #define OMAP4_KBD_IRQENABLE		0x1C
41 #define OMAP4_KBD_WAKEUPENABLE		0x20
42 #define OMAP4_KBD_PENDING		0x24
43 #define OMAP4_KBD_CTRL			0x28
44 #define OMAP4_KBD_DEBOUNCINGTIME	0x2C
45 #define OMAP4_KBD_LONGKEYTIME		0x30
46 #define OMAP4_KBD_TIMEOUT		0x34
47 #define OMAP4_KBD_STATEMACHINE		0x38
48 #define OMAP4_KBD_ROWINPUTS		0x3C
49 #define OMAP4_KBD_COLUMNOUTPUTS		0x40
50 #define OMAP4_KBD_FULLCODE31_0		0x44
51 #define OMAP4_KBD_FULLCODE63_32		0x48
52 
53 /* OMAP4 bit definitions */
54 #define OMAP4_DEF_IRQENABLE_EVENTEN	BIT(0)
55 #define OMAP4_DEF_IRQENABLE_LONGKEY	BIT(1)
56 #define OMAP4_DEF_WUP_EVENT_ENA		BIT(0)
57 #define OMAP4_DEF_WUP_LONG_KEY_ENA	BIT(1)
58 #define OMAP4_DEF_CTRL_NOSOFTMODE	BIT(1)
59 #define OMAP4_DEF_CTRL_PTV_SHIFT	2
60 
61 /* OMAP4 values */
62 #define OMAP4_VAL_IRQDISABLE		0x0
63 
64 /*
65  * Errata i689: If a key is released for a time shorter than debounce time,
66  * the keyboard will idle and never detect the key release. The workaround
67  * is to use at least a 12ms debounce time. See omap5432 TRM chapter
68  * "26.4.6.2 Keyboard Controller Timer" for more information.
69  */
70 #define OMAP4_KEYPAD_PTV_DIV_128        0x6
71 #define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv)     \
72 	((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
73 #define OMAP4_VAL_DEBOUNCINGTIME_16MS					\
74 	OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)
75 
76 enum {
77 	KBD_REVISION_OMAP4 = 0,
78 	KBD_REVISION_OMAP5,
79 };
80 
81 struct omap4_keypad {
82 	struct input_dev *input;
83 
84 	void __iomem *base;
85 	bool irq_wake_enabled;
86 	unsigned int irq;
87 
88 	unsigned int rows;
89 	unsigned int cols;
90 	u32 reg_offset;
91 	u32 irqreg_offset;
92 	unsigned int row_shift;
93 	bool no_autorepeat;
94 	unsigned char key_state[8];
95 	unsigned short *keymap;
96 };
97 
98 static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
99 {
100 	return __raw_readl(keypad_data->base +
101 				keypad_data->reg_offset + offset);
102 }
103 
104 static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
105 {
106 	__raw_writel(value,
107 		     keypad_data->base + keypad_data->reg_offset + offset);
108 }
109 
110 static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
111 {
112 	return __raw_readl(keypad_data->base +
113 				keypad_data->irqreg_offset + offset);
114 }
115 
116 static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
117 			     u32 offset, u32 value)
118 {
119 	__raw_writel(value,
120 		     keypad_data->base + keypad_data->irqreg_offset + offset);
121 }
122 
123 
124 /* Interrupt handlers */
125 static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
126 {
127 	struct omap4_keypad *keypad_data = dev_id;
128 
129 	if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS)) {
130 		/* Disable interrupts */
131 		kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
132 				 OMAP4_VAL_IRQDISABLE);
133 		return IRQ_WAKE_THREAD;
134 	}
135 
136 	return IRQ_NONE;
137 }
138 
139 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
140 {
141 	struct omap4_keypad *keypad_data = dev_id;
142 	struct input_dev *input_dev = keypad_data->input;
143 	unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
144 	unsigned int col, row, code, changed;
145 	u32 *new_state = (u32 *) key_state;
146 
147 	*new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
148 	*(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
149 
150 	for (row = 0; row < keypad_data->rows; row++) {
151 		changed = key_state[row] ^ keypad_data->key_state[row];
152 		if (!changed)
153 			continue;
154 
155 		for (col = 0; col < keypad_data->cols; col++) {
156 			if (changed & (1 << col)) {
157 				code = MATRIX_SCAN_CODE(row, col,
158 						keypad_data->row_shift);
159 				input_event(input_dev, EV_MSC, MSC_SCAN, code);
160 				input_report_key(input_dev,
161 						 keypad_data->keymap[code],
162 						 key_state[row] & (1 << col));
163 			}
164 		}
165 	}
166 
167 	input_sync(input_dev);
168 
169 	memcpy(keypad_data->key_state, key_state,
170 		sizeof(keypad_data->key_state));
171 
172 	/* clear pending interrupts */
173 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
174 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
175 
176 	/* enable interrupts */
177 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
178 		OMAP4_DEF_IRQENABLE_EVENTEN |
179 				OMAP4_DEF_IRQENABLE_LONGKEY);
180 
181 	return IRQ_HANDLED;
182 }
183 
184 static int omap4_keypad_open(struct input_dev *input)
185 {
186 	struct omap4_keypad *keypad_data = input_get_drvdata(input);
187 
188 	pm_runtime_get_sync(input->dev.parent);
189 
190 	disable_irq(keypad_data->irq);
191 
192 	kbd_writel(keypad_data, OMAP4_KBD_CTRL,
193 			OMAP4_DEF_CTRL_NOSOFTMODE |
194 			(OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
195 	kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
196 			OMAP4_VAL_DEBOUNCINGTIME_16MS);
197 	/* clear pending interrupts */
198 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
199 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
200 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
201 			OMAP4_DEF_IRQENABLE_EVENTEN |
202 				OMAP4_DEF_IRQENABLE_LONGKEY);
203 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
204 			OMAP4_DEF_WUP_EVENT_ENA | OMAP4_DEF_WUP_LONG_KEY_ENA);
205 
206 	enable_irq(keypad_data->irq);
207 
208 	return 0;
209 }
210 
211 static void omap4_keypad_close(struct input_dev *input)
212 {
213 	struct omap4_keypad *keypad_data = input_get_drvdata(input);
214 
215 	disable_irq(keypad_data->irq);
216 
217 	/* Disable interrupts */
218 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
219 			 OMAP4_VAL_IRQDISABLE);
220 
221 	/* clear pending interrupts */
222 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
223 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
224 
225 	enable_irq(keypad_data->irq);
226 
227 	pm_runtime_put_sync(input->dev.parent);
228 }
229 
230 static int omap4_keypad_parse_dt(struct device *dev,
231 				 struct omap4_keypad *keypad_data)
232 {
233 	struct device_node *np = dev->of_node;
234 	int err;
235 
236 	err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
237 					     &keypad_data->cols);
238 	if (err)
239 		return err;
240 
241 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
242 		keypad_data->no_autorepeat = true;
243 
244 	return 0;
245 }
246 
247 static int omap4_keypad_probe(struct platform_device *pdev)
248 {
249 	struct omap4_keypad *keypad_data;
250 	struct input_dev *input_dev;
251 	struct resource *res;
252 	unsigned int max_keys;
253 	int rev;
254 	int irq;
255 	int error;
256 
257 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
258 	if (!res) {
259 		dev_err(&pdev->dev, "no base address specified\n");
260 		return -EINVAL;
261 	}
262 
263 	irq = platform_get_irq(pdev, 0);
264 	if (!irq) {
265 		dev_err(&pdev->dev, "no keyboard irq assigned\n");
266 		return -EINVAL;
267 	}
268 
269 	keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
270 	if (!keypad_data) {
271 		dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
272 		return -ENOMEM;
273 	}
274 
275 	keypad_data->irq = irq;
276 
277 	error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
278 	if (error)
279 		goto err_free_keypad;
280 
281 	res = request_mem_region(res->start, resource_size(res), pdev->name);
282 	if (!res) {
283 		dev_err(&pdev->dev, "can't request mem region\n");
284 		error = -EBUSY;
285 		goto err_free_keypad;
286 	}
287 
288 	keypad_data->base = ioremap(res->start, resource_size(res));
289 	if (!keypad_data->base) {
290 		dev_err(&pdev->dev, "can't ioremap mem resource\n");
291 		error = -ENOMEM;
292 		goto err_release_mem;
293 	}
294 
295 
296 	/*
297 	 * Enable clocks for the keypad module so that we can read
298 	 * revision register.
299 	 */
300 	pm_runtime_enable(&pdev->dev);
301 	error = pm_runtime_get_sync(&pdev->dev);
302 	if (error) {
303 		dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
304 		goto err_unmap;
305 	}
306 	rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
307 	rev &= 0x03 << 30;
308 	rev >>= 30;
309 	switch (rev) {
310 	case KBD_REVISION_OMAP4:
311 		keypad_data->reg_offset = 0x00;
312 		keypad_data->irqreg_offset = 0x00;
313 		break;
314 	case KBD_REVISION_OMAP5:
315 		keypad_data->reg_offset = 0x10;
316 		keypad_data->irqreg_offset = 0x0c;
317 		break;
318 	default:
319 		dev_err(&pdev->dev,
320 			"Keypad reports unsupported revision %d", rev);
321 		error = -EINVAL;
322 		goto err_pm_put_sync;
323 	}
324 
325 	/* input device allocation */
326 	keypad_data->input = input_dev = input_allocate_device();
327 	if (!input_dev) {
328 		error = -ENOMEM;
329 		goto err_pm_put_sync;
330 	}
331 
332 	input_dev->name = pdev->name;
333 	input_dev->dev.parent = &pdev->dev;
334 	input_dev->id.bustype = BUS_HOST;
335 	input_dev->id.vendor = 0x0001;
336 	input_dev->id.product = 0x0001;
337 	input_dev->id.version = 0x0001;
338 
339 	input_dev->open = omap4_keypad_open;
340 	input_dev->close = omap4_keypad_close;
341 
342 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
343 	if (!keypad_data->no_autorepeat)
344 		__set_bit(EV_REP, input_dev->evbit);
345 
346 	input_set_drvdata(input_dev, keypad_data);
347 
348 	keypad_data->row_shift = get_count_order(keypad_data->cols);
349 	max_keys = keypad_data->rows << keypad_data->row_shift;
350 	keypad_data->keymap = kcalloc(max_keys,
351 				      sizeof(keypad_data->keymap[0]),
352 				      GFP_KERNEL);
353 	if (!keypad_data->keymap) {
354 		dev_err(&pdev->dev, "Not enough memory for keymap\n");
355 		error = -ENOMEM;
356 		goto err_free_input;
357 	}
358 
359 	error = matrix_keypad_build_keymap(NULL, NULL,
360 					   keypad_data->rows, keypad_data->cols,
361 					   keypad_data->keymap, input_dev);
362 	if (error) {
363 		dev_err(&pdev->dev, "failed to build keymap\n");
364 		goto err_free_keymap;
365 	}
366 
367 	error = request_threaded_irq(keypad_data->irq, omap4_keypad_irq_handler,
368 				     omap4_keypad_irq_thread_fn, 0,
369 				     "omap4-keypad", keypad_data);
370 	if (error) {
371 		dev_err(&pdev->dev, "failed to register interrupt\n");
372 		goto err_free_keymap;
373 	}
374 
375 	device_init_wakeup(&pdev->dev, true);
376 	pm_runtime_put_sync(&pdev->dev);
377 
378 	error = input_register_device(keypad_data->input);
379 	if (error < 0) {
380 		dev_err(&pdev->dev, "failed to register input device\n");
381 		goto err_pm_disable;
382 	}
383 
384 	platform_set_drvdata(pdev, keypad_data);
385 	return 0;
386 
387 err_pm_disable:
388 	pm_runtime_disable(&pdev->dev);
389 	free_irq(keypad_data->irq, keypad_data);
390 err_free_keymap:
391 	kfree(keypad_data->keymap);
392 err_free_input:
393 	input_free_device(input_dev);
394 err_pm_put_sync:
395 	pm_runtime_put_sync(&pdev->dev);
396 err_unmap:
397 	iounmap(keypad_data->base);
398 err_release_mem:
399 	release_mem_region(res->start, resource_size(res));
400 err_free_keypad:
401 	kfree(keypad_data);
402 	return error;
403 }
404 
405 static int omap4_keypad_remove(struct platform_device *pdev)
406 {
407 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
408 	struct resource *res;
409 
410 	free_irq(keypad_data->irq, keypad_data);
411 
412 	pm_runtime_disable(&pdev->dev);
413 
414 	input_unregister_device(keypad_data->input);
415 
416 	iounmap(keypad_data->base);
417 
418 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
419 	release_mem_region(res->start, resource_size(res));
420 
421 	kfree(keypad_data->keymap);
422 	kfree(keypad_data);
423 
424 	return 0;
425 }
426 
427 static const struct of_device_id omap_keypad_dt_match[] = {
428 	{ .compatible = "ti,omap4-keypad" },
429 	{},
430 };
431 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
432 
433 #ifdef CONFIG_PM_SLEEP
434 static int omap4_keypad_suspend(struct device *dev)
435 {
436 	struct platform_device *pdev = to_platform_device(dev);
437 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
438 	int error;
439 
440 	if (device_may_wakeup(&pdev->dev)) {
441 		error = enable_irq_wake(keypad_data->irq);
442 		if (!error)
443 			keypad_data->irq_wake_enabled = true;
444 	}
445 
446 	return 0;
447 }
448 
449 static int omap4_keypad_resume(struct device *dev)
450 {
451 	struct platform_device *pdev = to_platform_device(dev);
452 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
453 
454 	if (device_may_wakeup(&pdev->dev) && keypad_data->irq_wake_enabled) {
455 		disable_irq_wake(keypad_data->irq);
456 		keypad_data->irq_wake_enabled = false;
457 	}
458 
459 	return 0;
460 }
461 #endif
462 
463 static SIMPLE_DEV_PM_OPS(omap4_keypad_pm_ops,
464 			 omap4_keypad_suspend, omap4_keypad_resume);
465 
466 static struct platform_driver omap4_keypad_driver = {
467 	.probe		= omap4_keypad_probe,
468 	.remove		= omap4_keypad_remove,
469 	.driver		= {
470 		.name	= "omap4-keypad",
471 		.pm	= &omap4_keypad_pm_ops,
472 		.of_match_table = omap_keypad_dt_match,
473 	},
474 };
475 module_platform_driver(omap4_keypad_driver);
476 
477 MODULE_AUTHOR("Texas Instruments");
478 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
479 MODULE_LICENSE("GPL");
480 MODULE_ALIAS("platform:omap4-keypad");
481