1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * SuperH KEYSC Keypad Driver
4  *
5  * Copyright (C) 2008 Magnus Damm
6  *
7  * Based on gpio_keys.c, Copyright 2005 Phil Blundell
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/delay.h>
15 #include <linux/platform_device.h>
16 #include <linux/input.h>
17 #include <linux/input/sh_keysc.h>
18 #include <linux/bitmap.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/io.h>
21 #include <linux/slab.h>
22 
23 static const struct {
24 	unsigned char kymd, keyout, keyin;
25 } sh_keysc_mode[] = {
26 	[SH_KEYSC_MODE_1] = { 0, 6, 5 },
27 	[SH_KEYSC_MODE_2] = { 1, 5, 6 },
28 	[SH_KEYSC_MODE_3] = { 2, 4, 7 },
29 	[SH_KEYSC_MODE_4] = { 3, 6, 6 },
30 	[SH_KEYSC_MODE_5] = { 4, 6, 7 },
31 	[SH_KEYSC_MODE_6] = { 5, 8, 8 },
32 };
33 
34 struct sh_keysc_priv {
35 	void __iomem *iomem_base;
36 	DECLARE_BITMAP(last_keys, SH_KEYSC_MAXKEYS);
37 	struct input_dev *input;
38 	struct sh_keysc_info pdata;
39 };
40 
41 #define KYCR1 0
42 #define KYCR2 1
43 #define KYINDR 2
44 #define KYOUTDR 3
45 
46 #define KYCR2_IRQ_LEVEL    0x10
47 #define KYCR2_IRQ_DISABLED 0x00
48 
49 static unsigned long sh_keysc_read(struct sh_keysc_priv *p, int reg_nr)
50 {
51 	return ioread16(p->iomem_base + (reg_nr << 2));
52 }
53 
54 static void sh_keysc_write(struct sh_keysc_priv *p, int reg_nr,
55 			   unsigned long value)
56 {
57 	iowrite16(value, p->iomem_base + (reg_nr << 2));
58 }
59 
60 static void sh_keysc_level_mode(struct sh_keysc_priv *p,
61 				unsigned long keys_set)
62 {
63 	struct sh_keysc_info *pdata = &p->pdata;
64 
65 	sh_keysc_write(p, KYOUTDR, 0);
66 	sh_keysc_write(p, KYCR2, KYCR2_IRQ_LEVEL | (keys_set << 8));
67 
68 	if (pdata->kycr2_delay)
69 		udelay(pdata->kycr2_delay);
70 }
71 
72 static void sh_keysc_map_dbg(struct device *dev, unsigned long *map,
73 			     const char *str)
74 {
75 	int k;
76 
77 	for (k = 0; k < BITS_TO_LONGS(SH_KEYSC_MAXKEYS); k++)
78 		dev_dbg(dev, "%s[%d] 0x%lx\n", str, k, map[k]);
79 }
80 
81 static irqreturn_t sh_keysc_isr(int irq, void *dev_id)
82 {
83 	struct platform_device *pdev = dev_id;
84 	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
85 	struct sh_keysc_info *pdata = &priv->pdata;
86 	int keyout_nr = sh_keysc_mode[pdata->mode].keyout;
87 	int keyin_nr = sh_keysc_mode[pdata->mode].keyin;
88 	DECLARE_BITMAP(keys, SH_KEYSC_MAXKEYS);
89 	DECLARE_BITMAP(keys0, SH_KEYSC_MAXKEYS);
90 	DECLARE_BITMAP(keys1, SH_KEYSC_MAXKEYS);
91 	unsigned char keyin_set, tmp;
92 	int i, k, n;
93 
94 	dev_dbg(&pdev->dev, "isr!\n");
95 
96 	bitmap_fill(keys1, SH_KEYSC_MAXKEYS);
97 	bitmap_zero(keys0, SH_KEYSC_MAXKEYS);
98 
99 	do {
100 		bitmap_zero(keys, SH_KEYSC_MAXKEYS);
101 		keyin_set = 0;
102 
103 		sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
104 
105 		for (i = 0; i < keyout_nr; i++) {
106 			n = keyin_nr * i;
107 
108 			/* drive one KEYOUT pin low, read KEYIN pins */
109 			sh_keysc_write(priv, KYOUTDR, 0xffff ^ (3 << (i * 2)));
110 			udelay(pdata->delay);
111 			tmp = sh_keysc_read(priv, KYINDR);
112 
113 			/* set bit if key press has been detected */
114 			for (k = 0; k < keyin_nr; k++) {
115 				if (tmp & (1 << k))
116 					__set_bit(n + k, keys);
117 			}
118 
119 			/* keep track of which KEYIN bits that have been set */
120 			keyin_set |= tmp ^ ((1 << keyin_nr) - 1);
121 		}
122 
123 		sh_keysc_level_mode(priv, keyin_set);
124 
125 		bitmap_complement(keys, keys, SH_KEYSC_MAXKEYS);
126 		bitmap_and(keys1, keys1, keys, SH_KEYSC_MAXKEYS);
127 		bitmap_or(keys0, keys0, keys, SH_KEYSC_MAXKEYS);
128 
129 		sh_keysc_map_dbg(&pdev->dev, keys, "keys");
130 
131 	} while (sh_keysc_read(priv, KYCR2) & 0x01);
132 
133 	sh_keysc_map_dbg(&pdev->dev, priv->last_keys, "last_keys");
134 	sh_keysc_map_dbg(&pdev->dev, keys0, "keys0");
135 	sh_keysc_map_dbg(&pdev->dev, keys1, "keys1");
136 
137 	for (i = 0; i < SH_KEYSC_MAXKEYS; i++) {
138 		k = pdata->keycodes[i];
139 		if (!k)
140 			continue;
141 
142 		if (test_bit(i, keys0) == test_bit(i, priv->last_keys))
143 			continue;
144 
145 		if (test_bit(i, keys1) || test_bit(i, keys0)) {
146 			input_event(priv->input, EV_KEY, k, 1);
147 			__set_bit(i, priv->last_keys);
148 		}
149 
150 		if (!test_bit(i, keys1)) {
151 			input_event(priv->input, EV_KEY, k, 0);
152 			__clear_bit(i, priv->last_keys);
153 		}
154 
155 	}
156 	input_sync(priv->input);
157 
158 	return IRQ_HANDLED;
159 }
160 
161 static int sh_keysc_probe(struct platform_device *pdev)
162 {
163 	struct sh_keysc_priv *priv;
164 	struct sh_keysc_info *pdata;
165 	struct resource *res;
166 	struct input_dev *input;
167 	int i;
168 	int irq, error;
169 
170 	if (!dev_get_platdata(&pdev->dev)) {
171 		dev_err(&pdev->dev, "no platform data defined\n");
172 		error = -EINVAL;
173 		goto err0;
174 	}
175 
176 	error = -ENXIO;
177 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
178 	if (res == NULL) {
179 		dev_err(&pdev->dev, "failed to get I/O memory\n");
180 		goto err0;
181 	}
182 
183 	irq = platform_get_irq(pdev, 0);
184 	if (irq < 0) {
185 		dev_err(&pdev->dev, "failed to get irq\n");
186 		goto err0;
187 	}
188 
189 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
190 	if (priv == NULL) {
191 		dev_err(&pdev->dev, "failed to allocate driver data\n");
192 		error = -ENOMEM;
193 		goto err0;
194 	}
195 
196 	platform_set_drvdata(pdev, priv);
197 	memcpy(&priv->pdata, dev_get_platdata(&pdev->dev), sizeof(priv->pdata));
198 	pdata = &priv->pdata;
199 
200 	priv->iomem_base = ioremap_nocache(res->start, resource_size(res));
201 	if (priv->iomem_base == NULL) {
202 		dev_err(&pdev->dev, "failed to remap I/O memory\n");
203 		error = -ENXIO;
204 		goto err1;
205 	}
206 
207 	priv->input = input_allocate_device();
208 	if (!priv->input) {
209 		dev_err(&pdev->dev, "failed to allocate input device\n");
210 		error = -ENOMEM;
211 		goto err2;
212 	}
213 
214 	input = priv->input;
215 	input->evbit[0] = BIT_MASK(EV_KEY);
216 
217 	input->name = pdev->name;
218 	input->phys = "sh-keysc-keys/input0";
219 	input->dev.parent = &pdev->dev;
220 
221 	input->id.bustype = BUS_HOST;
222 	input->id.vendor = 0x0001;
223 	input->id.product = 0x0001;
224 	input->id.version = 0x0100;
225 
226 	input->keycode = pdata->keycodes;
227 	input->keycodesize = sizeof(pdata->keycodes[0]);
228 	input->keycodemax = ARRAY_SIZE(pdata->keycodes);
229 
230 	error = request_threaded_irq(irq, NULL, sh_keysc_isr, IRQF_ONESHOT,
231 				     dev_name(&pdev->dev), pdev);
232 	if (error) {
233 		dev_err(&pdev->dev, "failed to request IRQ\n");
234 		goto err3;
235 	}
236 
237 	for (i = 0; i < SH_KEYSC_MAXKEYS; i++)
238 		__set_bit(pdata->keycodes[i], input->keybit);
239 	__clear_bit(KEY_RESERVED, input->keybit);
240 
241 	error = input_register_device(input);
242 	if (error) {
243 		dev_err(&pdev->dev, "failed to register input device\n");
244 		goto err4;
245 	}
246 
247 	pm_runtime_enable(&pdev->dev);
248 	pm_runtime_get_sync(&pdev->dev);
249 
250 	sh_keysc_write(priv, KYCR1, (sh_keysc_mode[pdata->mode].kymd << 8) |
251 		       pdata->scan_timing);
252 	sh_keysc_level_mode(priv, 0);
253 
254 	device_init_wakeup(&pdev->dev, 1);
255 
256 	return 0;
257 
258  err4:
259 	free_irq(irq, pdev);
260  err3:
261 	input_free_device(input);
262  err2:
263 	iounmap(priv->iomem_base);
264  err1:
265 	kfree(priv);
266  err0:
267 	return error;
268 }
269 
270 static int sh_keysc_remove(struct platform_device *pdev)
271 {
272 	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
273 
274 	sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
275 
276 	input_unregister_device(priv->input);
277 	free_irq(platform_get_irq(pdev, 0), pdev);
278 	iounmap(priv->iomem_base);
279 
280 	pm_runtime_put_sync(&pdev->dev);
281 	pm_runtime_disable(&pdev->dev);
282 
283 	kfree(priv);
284 
285 	return 0;
286 }
287 
288 #ifdef CONFIG_PM_SLEEP
289 static int sh_keysc_suspend(struct device *dev)
290 {
291 	struct platform_device *pdev = to_platform_device(dev);
292 	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
293 	int irq = platform_get_irq(pdev, 0);
294 	unsigned short value;
295 
296 	value = sh_keysc_read(priv, KYCR1);
297 
298 	if (device_may_wakeup(dev)) {
299 		sh_keysc_write(priv, KYCR1, value | 0x80);
300 		enable_irq_wake(irq);
301 	} else {
302 		sh_keysc_write(priv, KYCR1, value & ~0x80);
303 		pm_runtime_put_sync(dev);
304 	}
305 
306 	return 0;
307 }
308 
309 static int sh_keysc_resume(struct device *dev)
310 {
311 	struct platform_device *pdev = to_platform_device(dev);
312 	int irq = platform_get_irq(pdev, 0);
313 
314 	if (device_may_wakeup(dev))
315 		disable_irq_wake(irq);
316 	else
317 		pm_runtime_get_sync(dev);
318 
319 	return 0;
320 }
321 #endif
322 
323 static SIMPLE_DEV_PM_OPS(sh_keysc_dev_pm_ops,
324 			 sh_keysc_suspend, sh_keysc_resume);
325 
326 static struct platform_driver sh_keysc_device_driver = {
327 	.probe		= sh_keysc_probe,
328 	.remove		= sh_keysc_remove,
329 	.driver		= {
330 		.name	= "sh_keysc",
331 		.pm	= &sh_keysc_dev_pm_ops,
332 	}
333 };
334 module_platform_driver(sh_keysc_device_driver);
335 
336 MODULE_AUTHOR("Magnus Damm");
337 MODULE_DESCRIPTION("SuperH KEYSC Keypad Driver");
338 MODULE_LICENSE("GPL");
339