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 		return IRQ_WAKE_THREAD;
131 
132 	return IRQ_NONE;
133 }
134 
135 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
136 {
137 	struct omap4_keypad *keypad_data = dev_id;
138 	struct input_dev *input_dev = keypad_data->input;
139 	unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
140 	unsigned int col, row, code, changed;
141 	u32 *new_state = (u32 *) key_state;
142 
143 	*new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
144 	*(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
145 
146 	for (row = 0; row < keypad_data->rows; row++) {
147 		changed = key_state[row] ^ keypad_data->key_state[row];
148 		if (!changed)
149 			continue;
150 
151 		for (col = 0; col < keypad_data->cols; col++) {
152 			if (changed & (1 << col)) {
153 				code = MATRIX_SCAN_CODE(row, col,
154 						keypad_data->row_shift);
155 				input_event(input_dev, EV_MSC, MSC_SCAN, code);
156 				input_report_key(input_dev,
157 						 keypad_data->keymap[code],
158 						 key_state[row] & (1 << col));
159 			}
160 		}
161 	}
162 
163 	input_sync(input_dev);
164 
165 	memcpy(keypad_data->key_state, key_state,
166 		sizeof(keypad_data->key_state));
167 
168 	/* clear pending interrupts */
169 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
170 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
171 
172 	return IRQ_HANDLED;
173 }
174 
175 static int omap4_keypad_open(struct input_dev *input)
176 {
177 	struct omap4_keypad *keypad_data = input_get_drvdata(input);
178 
179 	pm_runtime_get_sync(input->dev.parent);
180 
181 	disable_irq(keypad_data->irq);
182 
183 	kbd_writel(keypad_data, OMAP4_KBD_CTRL,
184 			OMAP4_DEF_CTRL_NOSOFTMODE |
185 			(OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
186 	kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
187 			OMAP4_VAL_DEBOUNCINGTIME_16MS);
188 	/* clear pending interrupts */
189 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
190 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
191 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
192 			OMAP4_DEF_IRQENABLE_EVENTEN |
193 				OMAP4_DEF_IRQENABLE_LONGKEY);
194 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
195 			OMAP4_DEF_WUP_EVENT_ENA | OMAP4_DEF_WUP_LONG_KEY_ENA);
196 
197 	enable_irq(keypad_data->irq);
198 
199 	return 0;
200 }
201 
202 static void omap4_keypad_close(struct input_dev *input)
203 {
204 	struct omap4_keypad *keypad_data = input_get_drvdata(input);
205 
206 	disable_irq(keypad_data->irq);
207 
208 	/* Disable interrupts and wake-up events */
209 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
210 			 OMAP4_VAL_IRQDISABLE);
211 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
212 
213 	/* clear pending interrupts */
214 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
215 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
216 
217 	enable_irq(keypad_data->irq);
218 
219 	pm_runtime_put_sync(input->dev.parent);
220 }
221 
222 static int omap4_keypad_parse_dt(struct device *dev,
223 				 struct omap4_keypad *keypad_data)
224 {
225 	struct device_node *np = dev->of_node;
226 	int err;
227 
228 	err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
229 					     &keypad_data->cols);
230 	if (err)
231 		return err;
232 
233 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
234 		keypad_data->no_autorepeat = true;
235 
236 	return 0;
237 }
238 
239 static int omap4_keypad_probe(struct platform_device *pdev)
240 {
241 	struct omap4_keypad *keypad_data;
242 	struct input_dev *input_dev;
243 	struct resource *res;
244 	unsigned int max_keys;
245 	int rev;
246 	int irq;
247 	int error;
248 
249 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
250 	if (!res) {
251 		dev_err(&pdev->dev, "no base address specified\n");
252 		return -EINVAL;
253 	}
254 
255 	irq = platform_get_irq(pdev, 0);
256 	if (!irq) {
257 		dev_err(&pdev->dev, "no keyboard irq assigned\n");
258 		return -EINVAL;
259 	}
260 
261 	keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
262 	if (!keypad_data) {
263 		dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
264 		return -ENOMEM;
265 	}
266 
267 	keypad_data->irq = irq;
268 
269 	error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
270 	if (error)
271 		goto err_free_keypad;
272 
273 	res = request_mem_region(res->start, resource_size(res), pdev->name);
274 	if (!res) {
275 		dev_err(&pdev->dev, "can't request mem region\n");
276 		error = -EBUSY;
277 		goto err_free_keypad;
278 	}
279 
280 	keypad_data->base = ioremap(res->start, resource_size(res));
281 	if (!keypad_data->base) {
282 		dev_err(&pdev->dev, "can't ioremap mem resource\n");
283 		error = -ENOMEM;
284 		goto err_release_mem;
285 	}
286 
287 
288 	/*
289 	 * Enable clocks for the keypad module so that we can read
290 	 * revision register.
291 	 */
292 	pm_runtime_enable(&pdev->dev);
293 	error = pm_runtime_get_sync(&pdev->dev);
294 	if (error) {
295 		dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
296 		goto err_unmap;
297 	}
298 	rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
299 	rev &= 0x03 << 30;
300 	rev >>= 30;
301 	switch (rev) {
302 	case KBD_REVISION_OMAP4:
303 		keypad_data->reg_offset = 0x00;
304 		keypad_data->irqreg_offset = 0x00;
305 		break;
306 	case KBD_REVISION_OMAP5:
307 		keypad_data->reg_offset = 0x10;
308 		keypad_data->irqreg_offset = 0x0c;
309 		break;
310 	default:
311 		dev_err(&pdev->dev,
312 			"Keypad reports unsupported revision %d", rev);
313 		error = -EINVAL;
314 		goto err_pm_put_sync;
315 	}
316 
317 	/* input device allocation */
318 	keypad_data->input = input_dev = input_allocate_device();
319 	if (!input_dev) {
320 		error = -ENOMEM;
321 		goto err_pm_put_sync;
322 	}
323 
324 	input_dev->name = pdev->name;
325 	input_dev->dev.parent = &pdev->dev;
326 	input_dev->id.bustype = BUS_HOST;
327 	input_dev->id.vendor = 0x0001;
328 	input_dev->id.product = 0x0001;
329 	input_dev->id.version = 0x0001;
330 
331 	input_dev->open = omap4_keypad_open;
332 	input_dev->close = omap4_keypad_close;
333 
334 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
335 	if (!keypad_data->no_autorepeat)
336 		__set_bit(EV_REP, input_dev->evbit);
337 
338 	input_set_drvdata(input_dev, keypad_data);
339 
340 	keypad_data->row_shift = get_count_order(keypad_data->cols);
341 	max_keys = keypad_data->rows << keypad_data->row_shift;
342 	keypad_data->keymap = kcalloc(max_keys,
343 				      sizeof(keypad_data->keymap[0]),
344 				      GFP_KERNEL);
345 	if (!keypad_data->keymap) {
346 		dev_err(&pdev->dev, "Not enough memory for keymap\n");
347 		error = -ENOMEM;
348 		goto err_free_input;
349 	}
350 
351 	error = matrix_keypad_build_keymap(NULL, NULL,
352 					   keypad_data->rows, keypad_data->cols,
353 					   keypad_data->keymap, input_dev);
354 	if (error) {
355 		dev_err(&pdev->dev, "failed to build keymap\n");
356 		goto err_free_keymap;
357 	}
358 
359 	error = request_threaded_irq(keypad_data->irq, omap4_keypad_irq_handler,
360 				     omap4_keypad_irq_thread_fn, IRQF_ONESHOT,
361 				     "omap4-keypad", keypad_data);
362 	if (error) {
363 		dev_err(&pdev->dev, "failed to register interrupt\n");
364 		goto err_free_keymap;
365 	}
366 
367 	device_init_wakeup(&pdev->dev, true);
368 	pm_runtime_put_sync(&pdev->dev);
369 
370 	error = input_register_device(keypad_data->input);
371 	if (error < 0) {
372 		dev_err(&pdev->dev, "failed to register input device\n");
373 		goto err_pm_disable;
374 	}
375 
376 	platform_set_drvdata(pdev, keypad_data);
377 	return 0;
378 
379 err_pm_disable:
380 	pm_runtime_disable(&pdev->dev);
381 	free_irq(keypad_data->irq, keypad_data);
382 err_free_keymap:
383 	kfree(keypad_data->keymap);
384 err_free_input:
385 	input_free_device(input_dev);
386 err_pm_put_sync:
387 	pm_runtime_put_sync(&pdev->dev);
388 err_unmap:
389 	iounmap(keypad_data->base);
390 err_release_mem:
391 	release_mem_region(res->start, resource_size(res));
392 err_free_keypad:
393 	kfree(keypad_data);
394 	return error;
395 }
396 
397 static int omap4_keypad_remove(struct platform_device *pdev)
398 {
399 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
400 	struct resource *res;
401 
402 	free_irq(keypad_data->irq, keypad_data);
403 
404 	pm_runtime_disable(&pdev->dev);
405 
406 	input_unregister_device(keypad_data->input);
407 
408 	iounmap(keypad_data->base);
409 
410 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
411 	release_mem_region(res->start, resource_size(res));
412 
413 	kfree(keypad_data->keymap);
414 	kfree(keypad_data);
415 
416 	return 0;
417 }
418 
419 static const struct of_device_id omap_keypad_dt_match[] = {
420 	{ .compatible = "ti,omap4-keypad" },
421 	{},
422 };
423 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
424 
425 #ifdef CONFIG_PM_SLEEP
426 static int omap4_keypad_suspend(struct device *dev)
427 {
428 	struct platform_device *pdev = to_platform_device(dev);
429 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
430 	int error;
431 
432 	if (device_may_wakeup(&pdev->dev)) {
433 		error = enable_irq_wake(keypad_data->irq);
434 		if (!error)
435 			keypad_data->irq_wake_enabled = true;
436 	}
437 
438 	return 0;
439 }
440 
441 static int omap4_keypad_resume(struct device *dev)
442 {
443 	struct platform_device *pdev = to_platform_device(dev);
444 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
445 
446 	if (device_may_wakeup(&pdev->dev) && keypad_data->irq_wake_enabled) {
447 		disable_irq_wake(keypad_data->irq);
448 		keypad_data->irq_wake_enabled = false;
449 	}
450 
451 	return 0;
452 }
453 #endif
454 
455 static SIMPLE_DEV_PM_OPS(omap4_keypad_pm_ops,
456 			 omap4_keypad_suspend, omap4_keypad_resume);
457 
458 static struct platform_driver omap4_keypad_driver = {
459 	.probe		= omap4_keypad_probe,
460 	.remove		= omap4_keypad_remove,
461 	.driver		= {
462 		.name	= "omap4-keypad",
463 		.pm	= &omap4_keypad_pm_ops,
464 		.of_match_table = omap_keypad_dt_match,
465 	},
466 };
467 module_platform_driver(omap4_keypad_driver);
468 
469 MODULE_AUTHOR("Texas Instruments");
470 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
471 MODULE_LICENSE("GPL");
472 MODULE_ALIAS("platform:omap4-keypad");
473