1 /*
2  * Driver for the Cirrus EP93xx matrix keypad controller.
3  *
4  * Copyright (c) 2008 H Hartley Sweeten <hsweeten@visionengravers.com>
5  *
6  * Based on the pxa27x matrix keypad controller by Rodolfo Giometti.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * NOTE:
13  *
14  * The 3-key reset is triggered by pressing the 3 keys in
15  * Row 0, Columns 2, 4, and 7 at the same time.  This action can
16  * be disabled by setting the EP93XX_KEYPAD_DISABLE_3_KEY flag.
17  *
18  * Normal operation for the matrix does not autorepeat the key press.
19  * This action can be enabled by setting the EP93XX_KEYPAD_AUTOREPEAT
20  * flag.
21  */
22 
23 #include <linux/platform_device.h>
24 #include <linux/interrupt.h>
25 #include <linux/input.h>
26 #include <linux/clk.h>
27 
28 #include <mach/hardware.h>
29 #include <mach/gpio.h>
30 #include <mach/ep93xx_keypad.h>
31 
32 /*
33  * Keypad Interface Register offsets
34  */
35 #define KEY_INIT		0x00	/* Key Scan Initialization register */
36 #define KEY_DIAG		0x04	/* Key Scan Diagnostic register */
37 #define KEY_REG			0x08	/* Key Value Capture register */
38 
39 /* Key Scan Initialization Register bit defines */
40 #define KEY_INIT_DBNC_MASK	(0x00ff0000)
41 #define KEY_INIT_DBNC_SHIFT	(16)
42 #define KEY_INIT_DIS3KY		(1<<15)
43 #define KEY_INIT_DIAG		(1<<14)
44 #define KEY_INIT_BACK		(1<<13)
45 #define KEY_INIT_T2		(1<<12)
46 #define KEY_INIT_PRSCL_MASK	(0x000003ff)
47 #define KEY_INIT_PRSCL_SHIFT	(0)
48 
49 /* Key Scan Diagnostic Register bit defines */
50 #define KEY_DIAG_MASK		(0x0000003f)
51 #define KEY_DIAG_SHIFT		(0)
52 
53 /* Key Value Capture Register bit defines */
54 #define KEY_REG_K		(1<<15)
55 #define KEY_REG_INT		(1<<14)
56 #define KEY_REG_2KEYS		(1<<13)
57 #define KEY_REG_1KEY		(1<<12)
58 #define KEY_REG_KEY2_MASK	(0x00000fc0)
59 #define KEY_REG_KEY2_SHIFT	(6)
60 #define KEY_REG_KEY1_MASK	(0x0000003f)
61 #define KEY_REG_KEY1_SHIFT	(0)
62 
63 #define keypad_readl(off)	__raw_readl(keypad->mmio_base + (off))
64 #define keypad_writel(v, off)	__raw_writel((v), keypad->mmio_base + (off))
65 
66 #define MAX_MATRIX_KEY_NUM	(MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
67 
68 struct ep93xx_keypad {
69 	struct ep93xx_keypad_platform_data *pdata;
70 
71 	struct clk *clk;
72 	struct input_dev *input_dev;
73 	void __iomem *mmio_base;
74 
75 	int irq;
76 	int enabled;
77 
78 	int key1;
79 	int key2;
80 
81 	unsigned int matrix_keycodes[MAX_MATRIX_KEY_NUM];
82 };
83 
84 static void ep93xx_keypad_build_keycode(struct ep93xx_keypad *keypad)
85 {
86 	struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
87 	struct input_dev *input_dev = keypad->input_dev;
88 	int i;
89 
90 	for (i = 0; i < pdata->matrix_key_map_size; i++) {
91 		unsigned int key = pdata->matrix_key_map[i];
92 		int row = (key >> 28) & 0xf;
93 		int col = (key >> 24) & 0xf;
94 		int code = key & 0xffffff;
95 
96 		keypad->matrix_keycodes[(row << 3) + col] = code;
97 		__set_bit(code, input_dev->keybit);
98 	}
99 }
100 
101 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
102 {
103 	struct ep93xx_keypad *keypad = dev_id;
104 	struct input_dev *input_dev = keypad->input_dev;
105 	unsigned int status = keypad_readl(KEY_REG);
106 	int keycode, key1, key2;
107 
108 	keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
109 	key1 = keypad->matrix_keycodes[keycode];
110 
111 	keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
112 	key2 = keypad->matrix_keycodes[keycode];
113 
114 	if (status & KEY_REG_2KEYS) {
115 		if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
116 			input_report_key(input_dev, keypad->key1, 0);
117 
118 		if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
119 			input_report_key(input_dev, keypad->key2, 0);
120 
121 		input_report_key(input_dev, key1, 1);
122 		input_report_key(input_dev, key2, 1);
123 
124 		keypad->key1 = key1;
125 		keypad->key2 = key2;
126 
127 	} else if (status & KEY_REG_1KEY) {
128 		if (keypad->key1 && key1 != keypad->key1)
129 			input_report_key(input_dev, keypad->key1, 0);
130 
131 		if (keypad->key2 && key1 != keypad->key2)
132 			input_report_key(input_dev, keypad->key2, 0);
133 
134 		input_report_key(input_dev, key1, 1);
135 
136 		keypad->key1 = key1;
137 		keypad->key2 = 0;
138 
139 	} else {
140 		input_report_key(input_dev, keypad->key1, 0);
141 		input_report_key(input_dev, keypad->key2, 0);
142 
143 		keypad->key1 = keypad->key2 = 0;
144 	}
145 	input_sync(input_dev);
146 
147 	return IRQ_HANDLED;
148 }
149 
150 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
151 {
152 	struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
153 	unsigned int val = 0;
154 
155 	clk_set_rate(keypad->clk, pdata->flags & EP93XX_KEYPAD_KDIV);
156 
157 	if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
158 		val |= KEY_INIT_DIS3KY;
159 	if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
160 		val |= KEY_INIT_DIAG;
161 	if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
162 		val |= KEY_INIT_BACK;
163 	if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
164 		val |= KEY_INIT_T2;
165 
166 	val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
167 
168 	val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
169 
170 	keypad_writel(val, KEY_INIT);
171 }
172 
173 static int ep93xx_keypad_open(struct input_dev *pdev)
174 {
175 	struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
176 
177 	if (!keypad->enabled) {
178 		ep93xx_keypad_config(keypad);
179 		clk_enable(keypad->clk);
180 		keypad->enabled = 1;
181 	}
182 
183 	return 0;
184 }
185 
186 static void ep93xx_keypad_close(struct input_dev *pdev)
187 {
188 	struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
189 
190 	if (keypad->enabled) {
191 		clk_disable(keypad->clk);
192 		keypad->enabled = 0;
193 	}
194 }
195 
196 
197 #ifdef CONFIG_PM
198 /*
199  * NOTE: I don't know if this is correct, or will work on the ep93xx.
200  *
201  * None of the existing ep93xx drivers have power management support.
202  * But, this is basically what the pxa27x_keypad driver does.
203  */
204 static int ep93xx_keypad_suspend(struct platform_device *pdev,
205 				 pm_message_t state)
206 {
207 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
208 	struct input_dev *input_dev = keypad->input_dev;
209 
210 	mutex_lock(&input_dev->mutex);
211 
212 	if (keypad->enabled) {
213 		clk_disable(keypad->clk);
214 		keypad->enabled = 0;
215 	}
216 
217 	mutex_unlock(&input_dev->mutex);
218 
219 	if (device_may_wakeup(&pdev->dev))
220 		enable_irq_wake(keypad->irq);
221 
222 	return 0;
223 }
224 
225 static int ep93xx_keypad_resume(struct platform_device *pdev)
226 {
227 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
228 	struct input_dev *input_dev = keypad->input_dev;
229 
230 	if (device_may_wakeup(&pdev->dev))
231 		disable_irq_wake(keypad->irq);
232 
233 	mutex_lock(&input_dev->mutex);
234 
235 	if (input_dev->users) {
236 		if (!keypad->enabled) {
237 			ep93xx_keypad_config(keypad);
238 			clk_enable(keypad->clk);
239 			keypad->enabled = 1;
240 		}
241 	}
242 
243 	mutex_unlock(&input_dev->mutex);
244 
245 	return 0;
246 }
247 #else	/* !CONFIG_PM */
248 #define ep93xx_keypad_suspend	NULL
249 #define ep93xx_keypad_resume	NULL
250 #endif	/* !CONFIG_PM */
251 
252 static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
253 {
254 	struct ep93xx_keypad *keypad;
255 	struct ep93xx_keypad_platform_data *pdata = pdev->dev.platform_data;
256 	struct input_dev *input_dev;
257 	struct resource *res;
258 	int irq, err, i, gpio;
259 
260 	if (!pdata ||
261 	    !pdata->matrix_key_rows ||
262 	    pdata->matrix_key_rows > MAX_MATRIX_KEY_ROWS ||
263 	    !pdata->matrix_key_cols ||
264 	    pdata->matrix_key_cols > MAX_MATRIX_KEY_COLS) {
265 		dev_err(&pdev->dev, "invalid or missing platform data\n");
266 		return -EINVAL;
267 	}
268 
269 	keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
270 	if (!keypad) {
271 		dev_err(&pdev->dev, "failed to allocate driver data\n");
272 		return -ENOMEM;
273 	}
274 
275 	keypad->pdata = pdata;
276 
277 	irq = platform_get_irq(pdev, 0);
278 	if (irq < 0) {
279 		dev_err(&pdev->dev, "failed to get keypad irq\n");
280 		err = -ENXIO;
281 		goto failed_free;
282 	}
283 
284 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
285 	if (!res) {
286 		dev_err(&pdev->dev, "failed to get I/O memory\n");
287 		err = -ENXIO;
288 		goto failed_free;
289 	}
290 
291 	res = request_mem_region(res->start, resource_size(res), pdev->name);
292 	if (!res) {
293 		dev_err(&pdev->dev, "failed to request I/O memory\n");
294 		err = -EBUSY;
295 		goto failed_free;
296 	}
297 
298 	keypad->mmio_base = ioremap(res->start, resource_size(res));
299 	if (keypad->mmio_base == NULL) {
300 		dev_err(&pdev->dev, "failed to remap I/O memory\n");
301 		err = -ENXIO;
302 		goto failed_free_mem;
303 	}
304 
305 	/* Request the needed GPIO's */
306 	gpio = EP93XX_GPIO_LINE_ROW0;
307 	for (i = 0; i < keypad->pdata->matrix_key_rows; i++, gpio++) {
308 		err = gpio_request(gpio, pdev->name);
309 		if (err) {
310 			dev_err(&pdev->dev, "failed to request gpio-%d\n",
311 				gpio);
312 			goto failed_free_rows;
313 		}
314 	}
315 
316 	gpio = EP93XX_GPIO_LINE_COL0;
317 	for (i = 0; i < keypad->pdata->matrix_key_cols; i++, gpio++) {
318 		err = gpio_request(gpio, pdev->name);
319 		if (err) {
320 			dev_err(&pdev->dev, "failed to request gpio-%d\n",
321 				gpio);
322 			goto failed_free_cols;
323 		}
324 	}
325 
326 	keypad->clk = clk_get(&pdev->dev, "key_clk");
327 	if (IS_ERR(keypad->clk)) {
328 		dev_err(&pdev->dev, "failed to get keypad clock\n");
329 		err = PTR_ERR(keypad->clk);
330 		goto failed_free_io;
331 	}
332 
333 	/* Create and register the input driver */
334 	input_dev = input_allocate_device();
335 	if (!input_dev) {
336 		dev_err(&pdev->dev, "failed to allocate input device\n");
337 		err = -ENOMEM;
338 		goto failed_put_clk;
339 	}
340 
341 	keypad->input_dev = input_dev;
342 
343 	input_dev->name = pdev->name;
344 	input_dev->id.bustype = BUS_HOST;
345 	input_dev->open = ep93xx_keypad_open;
346 	input_dev->close = ep93xx_keypad_close;
347 	input_dev->dev.parent = &pdev->dev;
348 	input_dev->keycode = keypad->matrix_keycodes;
349 	input_dev->keycodesize = sizeof(keypad->matrix_keycodes[0]);
350 	input_dev->keycodemax = ARRAY_SIZE(keypad->matrix_keycodes);
351 
352 	input_set_drvdata(input_dev, keypad);
353 
354 	input_dev->evbit[0] = BIT_MASK(EV_KEY);
355 	if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
356 		input_dev->evbit[0] |= BIT_MASK(EV_REP);
357 
358 	ep93xx_keypad_build_keycode(keypad);
359 	platform_set_drvdata(pdev, keypad);
360 
361 	err = request_irq(irq, ep93xx_keypad_irq_handler, IRQF_DISABLED,
362 				pdev->name, keypad);
363 	if (err) {
364 		dev_err(&pdev->dev, "failed to request IRQ\n");
365 		goto failed_free_dev;
366 	}
367 
368 	keypad->irq = irq;
369 
370 	/* Register the input device */
371 	err = input_register_device(input_dev);
372 	if (err) {
373 		dev_err(&pdev->dev, "failed to register input device\n");
374 		goto failed_free_irq;
375 	}
376 
377 	device_init_wakeup(&pdev->dev, 1);
378 
379 	return 0;
380 
381 failed_free_irq:
382 	free_irq(irq, pdev);
383 	platform_set_drvdata(pdev, NULL);
384 failed_free_dev:
385 	input_free_device(input_dev);
386 failed_put_clk:
387 	clk_put(keypad->clk);
388 failed_free_io:
389 	i = keypad->pdata->matrix_key_cols - 1;
390 	gpio = EP93XX_GPIO_LINE_COL0 + i;
391 failed_free_cols:
392 	for ( ; i >= 0; i--, gpio--)
393 		gpio_free(gpio);
394 	i = keypad->pdata->matrix_key_rows - 1;
395 	gpio = EP93XX_GPIO_LINE_ROW0 + i;
396 failed_free_rows:
397 	for ( ; i >= 0; i--, gpio--)
398 		gpio_free(gpio);
399 	iounmap(keypad->mmio_base);
400 failed_free_mem:
401 	release_mem_region(res->start, resource_size(res));
402 failed_free:
403 	kfree(keypad);
404 	return err;
405 }
406 
407 static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
408 {
409 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
410 	struct resource *res;
411 	int i, gpio;
412 
413 	free_irq(keypad->irq, pdev);
414 
415 	platform_set_drvdata(pdev, NULL);
416 
417 	if (keypad->enabled)
418 		clk_disable(keypad->clk);
419 	clk_put(keypad->clk);
420 
421 	input_unregister_device(keypad->input_dev);
422 
423 	i = keypad->pdata->matrix_key_cols - 1;
424 	gpio = EP93XX_GPIO_LINE_COL0 + i;
425 	for ( ; i >= 0; i--, gpio--)
426 		gpio_free(gpio);
427 
428 	i = keypad->pdata->matrix_key_rows - 1;
429 	gpio = EP93XX_GPIO_LINE_ROW0 + i;
430 	for ( ; i >= 0; i--, gpio--)
431 		gpio_free(gpio);
432 
433 	iounmap(keypad->mmio_base);
434 
435 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
436 	release_mem_region(res->start, resource_size(res));
437 
438 	kfree(keypad);
439 
440 	return 0;
441 }
442 
443 static struct platform_driver ep93xx_keypad_driver = {
444 	.driver		= {
445 		.name	= "ep93xx-keypad",
446 		.owner	= THIS_MODULE,
447 	},
448 	.probe		= ep93xx_keypad_probe,
449 	.remove		= __devexit_p(ep93xx_keypad_remove),
450 	.suspend	= ep93xx_keypad_suspend,
451 	.resume		= ep93xx_keypad_resume,
452 };
453 
454 static int __init ep93xx_keypad_init(void)
455 {
456 	return platform_driver_register(&ep93xx_keypad_driver);
457 }
458 
459 static void __exit ep93xx_keypad_exit(void)
460 {
461 	platform_driver_unregister(&ep93xx_keypad_driver);
462 }
463 
464 module_init(ep93xx_keypad_init);
465 module_exit(ep93xx_keypad_exit);
466 
467 MODULE_LICENSE("GPL");
468 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
469 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
470 MODULE_ALIAS("platform:ep93xx-keypad");
471