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/clk.h>
26 #include <linux/io.h>
27 #include <linux/input/matrix_keypad.h>
28 #include <linux/slab.h>
29 
30 #include <mach/hardware.h>
31 #include <mach/ep93xx_keypad.h>
32 
33 /*
34  * Keypad Interface Register offsets
35  */
36 #define KEY_INIT		0x00	/* Key Scan Initialization register */
37 #define KEY_DIAG		0x04	/* Key Scan Diagnostic register */
38 #define KEY_REG			0x08	/* Key Value Capture register */
39 
40 /* Key Scan Initialization Register bit defines */
41 #define KEY_INIT_DBNC_MASK	(0x00ff0000)
42 #define KEY_INIT_DBNC_SHIFT	(16)
43 #define KEY_INIT_DIS3KY		(1<<15)
44 #define KEY_INIT_DIAG		(1<<14)
45 #define KEY_INIT_BACK		(1<<13)
46 #define KEY_INIT_T2		(1<<12)
47 #define KEY_INIT_PRSCL_MASK	(0x000003ff)
48 #define KEY_INIT_PRSCL_SHIFT	(0)
49 
50 /* Key Scan Diagnostic Register bit defines */
51 #define KEY_DIAG_MASK		(0x0000003f)
52 #define KEY_DIAG_SHIFT		(0)
53 
54 /* Key Value Capture Register bit defines */
55 #define KEY_REG_K		(1<<15)
56 #define KEY_REG_INT		(1<<14)
57 #define KEY_REG_2KEYS		(1<<13)
58 #define KEY_REG_1KEY		(1<<12)
59 #define KEY_REG_KEY2_MASK	(0x00000fc0)
60 #define KEY_REG_KEY2_SHIFT	(6)
61 #define KEY_REG_KEY1_MASK	(0x0000003f)
62 #define KEY_REG_KEY1_SHIFT	(0)
63 
64 #define EP93XX_MATRIX_SIZE	(EP93XX_MATRIX_ROWS * EP93XX_MATRIX_COLS)
65 
66 struct ep93xx_keypad {
67 	struct ep93xx_keypad_platform_data *pdata;
68 	struct input_dev *input_dev;
69 	struct clk *clk;
70 
71 	void __iomem *mmio_base;
72 
73 	unsigned short keycodes[EP93XX_MATRIX_SIZE];
74 
75 	int key1;
76 	int key2;
77 
78 	int irq;
79 
80 	bool enabled;
81 };
82 
ep93xx_keypad_irq_handler(int irq,void * dev_id)83 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
84 {
85 	struct ep93xx_keypad *keypad = dev_id;
86 	struct input_dev *input_dev = keypad->input_dev;
87 	unsigned int status;
88 	int keycode, key1, key2;
89 
90 	status = __raw_readl(keypad->mmio_base + KEY_REG);
91 
92 	keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
93 	key1 = keypad->keycodes[keycode];
94 
95 	keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
96 	key2 = keypad->keycodes[keycode];
97 
98 	if (status & KEY_REG_2KEYS) {
99 		if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
100 			input_report_key(input_dev, keypad->key1, 0);
101 
102 		if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
103 			input_report_key(input_dev, keypad->key2, 0);
104 
105 		input_report_key(input_dev, key1, 1);
106 		input_report_key(input_dev, key2, 1);
107 
108 		keypad->key1 = key1;
109 		keypad->key2 = key2;
110 
111 	} else if (status & KEY_REG_1KEY) {
112 		if (keypad->key1 && key1 != keypad->key1)
113 			input_report_key(input_dev, keypad->key1, 0);
114 
115 		if (keypad->key2 && key1 != keypad->key2)
116 			input_report_key(input_dev, keypad->key2, 0);
117 
118 		input_report_key(input_dev, key1, 1);
119 
120 		keypad->key1 = key1;
121 		keypad->key2 = 0;
122 
123 	} else {
124 		input_report_key(input_dev, keypad->key1, 0);
125 		input_report_key(input_dev, keypad->key2, 0);
126 
127 		keypad->key1 = keypad->key2 = 0;
128 	}
129 	input_sync(input_dev);
130 
131 	return IRQ_HANDLED;
132 }
133 
ep93xx_keypad_config(struct ep93xx_keypad * keypad)134 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
135 {
136 	struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
137 	unsigned int val = 0;
138 
139 	if (pdata->flags & EP93XX_KEYPAD_KDIV)
140 		clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV4);
141 	else
142 		clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV16);
143 
144 	if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
145 		val |= KEY_INIT_DIS3KY;
146 	if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
147 		val |= KEY_INIT_DIAG;
148 	if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
149 		val |= KEY_INIT_BACK;
150 	if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
151 		val |= KEY_INIT_T2;
152 
153 	val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
154 
155 	val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
156 
157 	__raw_writel(val, keypad->mmio_base + KEY_INIT);
158 }
159 
ep93xx_keypad_open(struct input_dev * pdev)160 static int ep93xx_keypad_open(struct input_dev *pdev)
161 {
162 	struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
163 
164 	if (!keypad->enabled) {
165 		ep93xx_keypad_config(keypad);
166 		clk_enable(keypad->clk);
167 		keypad->enabled = true;
168 	}
169 
170 	return 0;
171 }
172 
ep93xx_keypad_close(struct input_dev * pdev)173 static void ep93xx_keypad_close(struct input_dev *pdev)
174 {
175 	struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
176 
177 	if (keypad->enabled) {
178 		clk_disable(keypad->clk);
179 		keypad->enabled = false;
180 	}
181 }
182 
183 
184 #ifdef CONFIG_PM
185 /*
186  * NOTE: I don't know if this is correct, or will work on the ep93xx.
187  *
188  * None of the existing ep93xx drivers have power management support.
189  * But, this is basically what the pxa27x_keypad driver does.
190  */
ep93xx_keypad_suspend(struct platform_device * pdev,pm_message_t state)191 static int ep93xx_keypad_suspend(struct platform_device *pdev,
192 				 pm_message_t state)
193 {
194 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
195 	struct input_dev *input_dev = keypad->input_dev;
196 
197 	mutex_lock(&input_dev->mutex);
198 
199 	if (keypad->enabled) {
200 		clk_disable(keypad->clk);
201 		keypad->enabled = false;
202 	}
203 
204 	mutex_unlock(&input_dev->mutex);
205 
206 	if (device_may_wakeup(&pdev->dev))
207 		enable_irq_wake(keypad->irq);
208 
209 	return 0;
210 }
211 
ep93xx_keypad_resume(struct platform_device * pdev)212 static int ep93xx_keypad_resume(struct platform_device *pdev)
213 {
214 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
215 	struct input_dev *input_dev = keypad->input_dev;
216 
217 	if (device_may_wakeup(&pdev->dev))
218 		disable_irq_wake(keypad->irq);
219 
220 	mutex_lock(&input_dev->mutex);
221 
222 	if (input_dev->users) {
223 		if (!keypad->enabled) {
224 			ep93xx_keypad_config(keypad);
225 			clk_enable(keypad->clk);
226 			keypad->enabled = true;
227 		}
228 	}
229 
230 	mutex_unlock(&input_dev->mutex);
231 
232 	return 0;
233 }
234 #else	/* !CONFIG_PM */
235 #define ep93xx_keypad_suspend	NULL
236 #define ep93xx_keypad_resume	NULL
237 #endif	/* !CONFIG_PM */
238 
ep93xx_keypad_probe(struct platform_device * pdev)239 static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
240 {
241 	struct ep93xx_keypad *keypad;
242 	const struct matrix_keymap_data *keymap_data;
243 	struct input_dev *input_dev;
244 	struct resource *res;
245 	int err;
246 
247 	keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
248 	if (!keypad)
249 		return -ENOMEM;
250 
251 	keypad->pdata = pdev->dev.platform_data;
252 	if (!keypad->pdata) {
253 		err = -EINVAL;
254 		goto failed_free;
255 	}
256 
257 	keymap_data = keypad->pdata->keymap_data;
258 	if (!keymap_data) {
259 		err = -EINVAL;
260 		goto failed_free;
261 	}
262 
263 	keypad->irq = platform_get_irq(pdev, 0);
264 	if (!keypad->irq) {
265 		err = -ENXIO;
266 		goto failed_free;
267 	}
268 
269 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
270 	if (!res) {
271 		err = -ENXIO;
272 		goto failed_free;
273 	}
274 
275 	res = request_mem_region(res->start, resource_size(res), pdev->name);
276 	if (!res) {
277 		err = -EBUSY;
278 		goto failed_free;
279 	}
280 
281 	keypad->mmio_base = ioremap(res->start, resource_size(res));
282 	if (keypad->mmio_base == NULL) {
283 		err = -ENXIO;
284 		goto failed_free_mem;
285 	}
286 
287 	err = ep93xx_keypad_acquire_gpio(pdev);
288 	if (err)
289 		goto failed_free_io;
290 
291 	keypad->clk = clk_get(&pdev->dev, NULL);
292 	if (IS_ERR(keypad->clk)) {
293 		err = PTR_ERR(keypad->clk);
294 		goto failed_free_gpio;
295 	}
296 
297 	input_dev = input_allocate_device();
298 	if (!input_dev) {
299 		err = -ENOMEM;
300 		goto failed_put_clk;
301 	}
302 
303 	keypad->input_dev = input_dev;
304 
305 	input_dev->name = pdev->name;
306 	input_dev->id.bustype = BUS_HOST;
307 	input_dev->open = ep93xx_keypad_open;
308 	input_dev->close = ep93xx_keypad_close;
309 	input_dev->dev.parent = &pdev->dev;
310 	input_dev->keycode = keypad->keycodes;
311 	input_dev->keycodesize = sizeof(keypad->keycodes[0]);
312 	input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
313 
314 	input_set_drvdata(input_dev, keypad);
315 
316 	input_dev->evbit[0] = BIT_MASK(EV_KEY);
317 	if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
318 		input_dev->evbit[0] |= BIT_MASK(EV_REP);
319 
320 	matrix_keypad_build_keymap(keymap_data, 3,
321 				   input_dev->keycode, input_dev->keybit);
322 	platform_set_drvdata(pdev, keypad);
323 
324 	err = request_irq(keypad->irq, ep93xx_keypad_irq_handler,
325 			  IRQF_DISABLED, pdev->name, keypad);
326 	if (err)
327 		goto failed_free_dev;
328 
329 	err = input_register_device(input_dev);
330 	if (err)
331 		goto failed_free_irq;
332 
333 	device_init_wakeup(&pdev->dev, 1);
334 
335 	return 0;
336 
337 failed_free_irq:
338 	free_irq(keypad->irq, pdev);
339 	platform_set_drvdata(pdev, NULL);
340 failed_free_dev:
341 	input_free_device(input_dev);
342 failed_put_clk:
343 	clk_put(keypad->clk);
344 failed_free_gpio:
345 	ep93xx_keypad_release_gpio(pdev);
346 failed_free_io:
347 	iounmap(keypad->mmio_base);
348 failed_free_mem:
349 	release_mem_region(res->start, resource_size(res));
350 failed_free:
351 	kfree(keypad);
352 	return err;
353 }
354 
ep93xx_keypad_remove(struct platform_device * pdev)355 static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
356 {
357 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
358 	struct resource *res;
359 
360 	free_irq(keypad->irq, pdev);
361 
362 	platform_set_drvdata(pdev, NULL);
363 
364 	if (keypad->enabled)
365 		clk_disable(keypad->clk);
366 	clk_put(keypad->clk);
367 
368 	input_unregister_device(keypad->input_dev);
369 
370 	ep93xx_keypad_release_gpio(pdev);
371 
372 	iounmap(keypad->mmio_base);
373 
374 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
375 	release_mem_region(res->start, resource_size(res));
376 
377 	kfree(keypad);
378 
379 	return 0;
380 }
381 
382 static struct platform_driver ep93xx_keypad_driver = {
383 	.driver		= {
384 		.name	= "ep93xx-keypad",
385 		.owner	= THIS_MODULE,
386 	},
387 	.probe		= ep93xx_keypad_probe,
388 	.remove		= __devexit_p(ep93xx_keypad_remove),
389 	.suspend	= ep93xx_keypad_suspend,
390 	.resume		= ep93xx_keypad_resume,
391 };
392 
ep93xx_keypad_init(void)393 static int __init ep93xx_keypad_init(void)
394 {
395 	return platform_driver_register(&ep93xx_keypad_driver);
396 }
397 
ep93xx_keypad_exit(void)398 static void __exit ep93xx_keypad_exit(void)
399 {
400 	platform_driver_unregister(&ep93xx_keypad_driver);
401 }
402 
403 module_init(ep93xx_keypad_init);
404 module_exit(ep93xx_keypad_exit);
405 
406 MODULE_LICENSE("GPL");
407 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
408 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
409 MODULE_ALIAS("platform:ep93xx-keypad");
410