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