1 /*
2  * SuperH KEYSC Keypad Driver
3  *
4  * Copyright (C) 2008 Magnus Damm
5  *
6  * Based on gpio_keys.c, Copyright 2005 Phil Blundell
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 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/irq.h>
18 #include <linux/delay.h>
19 #include <linux/platform_device.h>
20 #include <linux/input.h>
21 #include <linux/input/sh_keysc.h>
22 #include <linux/bitmap.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/io.h>
25 #include <linux/slab.h>
26 
27 static const struct {
28 	unsigned char kymd, keyout, keyin;
29 } sh_keysc_mode[] = {
30 	[SH_KEYSC_MODE_1] = { 0, 6, 5 },
31 	[SH_KEYSC_MODE_2] = { 1, 5, 6 },
32 	[SH_KEYSC_MODE_3] = { 2, 4, 7 },
33 	[SH_KEYSC_MODE_4] = { 3, 6, 6 },
34 	[SH_KEYSC_MODE_5] = { 4, 6, 7 },
35 	[SH_KEYSC_MODE_6] = { 5, 8, 8 },
36 };
37 
38 struct sh_keysc_priv {
39 	void __iomem *iomem_base;
40 	DECLARE_BITMAP(last_keys, SH_KEYSC_MAXKEYS);
41 	struct input_dev *input;
42 	struct sh_keysc_info pdata;
43 };
44 
45 #define KYCR1 0
46 #define KYCR2 1
47 #define KYINDR 2
48 #define KYOUTDR 3
49 
50 #define KYCR2_IRQ_LEVEL    0x10
51 #define KYCR2_IRQ_DISABLED 0x00
52 
53 static unsigned long sh_keysc_read(struct sh_keysc_priv *p, int reg_nr)
54 {
55 	return ioread16(p->iomem_base + (reg_nr << 2));
56 }
57 
58 static void sh_keysc_write(struct sh_keysc_priv *p, int reg_nr,
59 			   unsigned long value)
60 {
61 	iowrite16(value, p->iomem_base + (reg_nr << 2));
62 }
63 
64 static void sh_keysc_level_mode(struct sh_keysc_priv *p,
65 				unsigned long keys_set)
66 {
67 	struct sh_keysc_info *pdata = &p->pdata;
68 
69 	sh_keysc_write(p, KYOUTDR, 0);
70 	sh_keysc_write(p, KYCR2, KYCR2_IRQ_LEVEL | (keys_set << 8));
71 
72 	if (pdata->kycr2_delay)
73 		udelay(pdata->kycr2_delay);
74 }
75 
76 static void sh_keysc_map_dbg(struct device *dev, unsigned long *map,
77 			     const char *str)
78 {
79 	int k;
80 
81 	for (k = 0; k < BITS_TO_LONGS(SH_KEYSC_MAXKEYS); k++)
82 		dev_dbg(dev, "%s[%d] 0x%lx\n", str, k, map[k]);
83 }
84 
85 static irqreturn_t sh_keysc_isr(int irq, void *dev_id)
86 {
87 	struct platform_device *pdev = dev_id;
88 	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
89 	struct sh_keysc_info *pdata = &priv->pdata;
90 	int keyout_nr = sh_keysc_mode[pdata->mode].keyout;
91 	int keyin_nr = sh_keysc_mode[pdata->mode].keyin;
92 	DECLARE_BITMAP(keys, SH_KEYSC_MAXKEYS);
93 	DECLARE_BITMAP(keys0, SH_KEYSC_MAXKEYS);
94 	DECLARE_BITMAP(keys1, SH_KEYSC_MAXKEYS);
95 	unsigned char keyin_set, tmp;
96 	int i, k, n;
97 
98 	dev_dbg(&pdev->dev, "isr!\n");
99 
100 	bitmap_fill(keys1, SH_KEYSC_MAXKEYS);
101 	bitmap_zero(keys0, SH_KEYSC_MAXKEYS);
102 
103 	do {
104 		bitmap_zero(keys, SH_KEYSC_MAXKEYS);
105 		keyin_set = 0;
106 
107 		sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
108 
109 		for (i = 0; i < keyout_nr; i++) {
110 			n = keyin_nr * i;
111 
112 			/* drive one KEYOUT pin low, read KEYIN pins */
113 			sh_keysc_write(priv, KYOUTDR, 0xffff ^ (3 << (i * 2)));
114 			udelay(pdata->delay);
115 			tmp = sh_keysc_read(priv, KYINDR);
116 
117 			/* set bit if key press has been detected */
118 			for (k = 0; k < keyin_nr; k++) {
119 				if (tmp & (1 << k))
120 					__set_bit(n + k, keys);
121 			}
122 
123 			/* keep track of which KEYIN bits that have been set */
124 			keyin_set |= tmp ^ ((1 << keyin_nr) - 1);
125 		}
126 
127 		sh_keysc_level_mode(priv, keyin_set);
128 
129 		bitmap_complement(keys, keys, SH_KEYSC_MAXKEYS);
130 		bitmap_and(keys1, keys1, keys, SH_KEYSC_MAXKEYS);
131 		bitmap_or(keys0, keys0, keys, SH_KEYSC_MAXKEYS);
132 
133 		sh_keysc_map_dbg(&pdev->dev, keys, "keys");
134 
135 	} while (sh_keysc_read(priv, KYCR2) & 0x01);
136 
137 	sh_keysc_map_dbg(&pdev->dev, priv->last_keys, "last_keys");
138 	sh_keysc_map_dbg(&pdev->dev, keys0, "keys0");
139 	sh_keysc_map_dbg(&pdev->dev, keys1, "keys1");
140 
141 	for (i = 0; i < SH_KEYSC_MAXKEYS; i++) {
142 		k = pdata->keycodes[i];
143 		if (!k)
144 			continue;
145 
146 		if (test_bit(i, keys0) == test_bit(i, priv->last_keys))
147 			continue;
148 
149 		if (test_bit(i, keys1) || test_bit(i, keys0)) {
150 			input_event(priv->input, EV_KEY, k, 1);
151 			__set_bit(i, priv->last_keys);
152 		}
153 
154 		if (!test_bit(i, keys1)) {
155 			input_event(priv->input, EV_KEY, k, 0);
156 			__clear_bit(i, priv->last_keys);
157 		}
158 
159 	}
160 	input_sync(priv->input);
161 
162 	return IRQ_HANDLED;
163 }
164 
165 static int __devinit sh_keysc_probe(struct platform_device *pdev)
166 {
167 	struct sh_keysc_priv *priv;
168 	struct sh_keysc_info *pdata;
169 	struct resource *res;
170 	struct input_dev *input;
171 	int i;
172 	int irq, error;
173 
174 	if (!pdev->dev.platform_data) {
175 		dev_err(&pdev->dev, "no platform data defined\n");
176 		error = -EINVAL;
177 		goto err0;
178 	}
179 
180 	error = -ENXIO;
181 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
182 	if (res == NULL) {
183 		dev_err(&pdev->dev, "failed to get I/O memory\n");
184 		goto err0;
185 	}
186 
187 	irq = platform_get_irq(pdev, 0);
188 	if (irq < 0) {
189 		dev_err(&pdev->dev, "failed to get irq\n");
190 		goto err0;
191 	}
192 
193 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
194 	if (priv == NULL) {
195 		dev_err(&pdev->dev, "failed to allocate driver data\n");
196 		error = -ENOMEM;
197 		goto err0;
198 	}
199 
200 	platform_set_drvdata(pdev, priv);
201 	memcpy(&priv->pdata, pdev->dev.platform_data, sizeof(priv->pdata));
202 	pdata = &priv->pdata;
203 
204 	priv->iomem_base = ioremap_nocache(res->start, resource_size(res));
205 	if (priv->iomem_base == NULL) {
206 		dev_err(&pdev->dev, "failed to remap I/O memory\n");
207 		error = -ENXIO;
208 		goto err1;
209 	}
210 
211 	priv->input = input_allocate_device();
212 	if (!priv->input) {
213 		dev_err(&pdev->dev, "failed to allocate input device\n");
214 		error = -ENOMEM;
215 		goto err2;
216 	}
217 
218 	input = priv->input;
219 	input->evbit[0] = BIT_MASK(EV_KEY);
220 
221 	input->name = pdev->name;
222 	input->phys = "sh-keysc-keys/input0";
223 	input->dev.parent = &pdev->dev;
224 
225 	input->id.bustype = BUS_HOST;
226 	input->id.vendor = 0x0001;
227 	input->id.product = 0x0001;
228 	input->id.version = 0x0100;
229 
230 	input->keycode = pdata->keycodes;
231 	input->keycodesize = sizeof(pdata->keycodes[0]);
232 	input->keycodemax = ARRAY_SIZE(pdata->keycodes);
233 
234 	error = request_threaded_irq(irq, NULL, sh_keysc_isr, IRQF_ONESHOT,
235 				     dev_name(&pdev->dev), pdev);
236 	if (error) {
237 		dev_err(&pdev->dev, "failed to request IRQ\n");
238 		goto err3;
239 	}
240 
241 	for (i = 0; i < SH_KEYSC_MAXKEYS; i++)
242 		__set_bit(pdata->keycodes[i], input->keybit);
243 	__clear_bit(KEY_RESERVED, input->keybit);
244 
245 	error = input_register_device(input);
246 	if (error) {
247 		dev_err(&pdev->dev, "failed to register input device\n");
248 		goto err4;
249 	}
250 
251 	pm_runtime_enable(&pdev->dev);
252 	pm_runtime_get_sync(&pdev->dev);
253 
254 	sh_keysc_write(priv, KYCR1, (sh_keysc_mode[pdata->mode].kymd << 8) |
255 		       pdata->scan_timing);
256 	sh_keysc_level_mode(priv, 0);
257 
258 	device_init_wakeup(&pdev->dev, 1);
259 
260 	return 0;
261 
262  err4:
263 	free_irq(irq, pdev);
264  err3:
265 	input_free_device(input);
266  err2:
267 	iounmap(priv->iomem_base);
268  err1:
269 	platform_set_drvdata(pdev, NULL);
270 	kfree(priv);
271  err0:
272 	return error;
273 }
274 
275 static int __devexit sh_keysc_remove(struct platform_device *pdev)
276 {
277 	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
278 
279 	sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
280 
281 	input_unregister_device(priv->input);
282 	free_irq(platform_get_irq(pdev, 0), pdev);
283 	iounmap(priv->iomem_base);
284 
285 	pm_runtime_put_sync(&pdev->dev);
286 	pm_runtime_disable(&pdev->dev);
287 
288 	platform_set_drvdata(pdev, NULL);
289 	kfree(priv);
290 
291 	return 0;
292 }
293 
294 #ifdef CONFIG_PM_SLEEP
295 static int sh_keysc_suspend(struct device *dev)
296 {
297 	struct platform_device *pdev = to_platform_device(dev);
298 	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
299 	int irq = platform_get_irq(pdev, 0);
300 	unsigned short value;
301 
302 	value = sh_keysc_read(priv, KYCR1);
303 
304 	if (device_may_wakeup(dev)) {
305 		sh_keysc_write(priv, KYCR1, value | 0x80);
306 		enable_irq_wake(irq);
307 	} else {
308 		sh_keysc_write(priv, KYCR1, value & ~0x80);
309 		pm_runtime_put_sync(dev);
310 	}
311 
312 	return 0;
313 }
314 
315 static int sh_keysc_resume(struct device *dev)
316 {
317 	struct platform_device *pdev = to_platform_device(dev);
318 	int irq = platform_get_irq(pdev, 0);
319 
320 	if (device_may_wakeup(dev))
321 		disable_irq_wake(irq);
322 	else
323 		pm_runtime_get_sync(dev);
324 
325 	return 0;
326 }
327 #endif
328 
329 static SIMPLE_DEV_PM_OPS(sh_keysc_dev_pm_ops,
330 			 sh_keysc_suspend, sh_keysc_resume);
331 
332 static struct platform_driver sh_keysc_device_driver = {
333 	.probe		= sh_keysc_probe,
334 	.remove		= __devexit_p(sh_keysc_remove),
335 	.driver		= {
336 		.name	= "sh_keysc",
337 		.pm	= &sh_keysc_dev_pm_ops,
338 	}
339 };
340 module_platform_driver(sh_keysc_device_driver);
341 
342 MODULE_AUTHOR("Magnus Damm");
343 MODULE_DESCRIPTION("SuperH KEYSC Keypad Driver");
344 MODULE_LICENSE("GPL");
345