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
23static 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
34struct 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
49static 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
54static 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
60static 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
72static 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
81static 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
161static 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		goto err0;
186
187	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
188	if (priv == NULL) {
189		dev_err(&pdev->dev, "failed to allocate driver data\n");
190		error = -ENOMEM;
191		goto err0;
192	}
193
194	platform_set_drvdata(pdev, priv);
195	memcpy(&priv->pdata, dev_get_platdata(&pdev->dev), sizeof(priv->pdata));
196	pdata = &priv->pdata;
197
198	priv->iomem_base = ioremap(res->start, resource_size(res));
199	if (priv->iomem_base == NULL) {
200		dev_err(&pdev->dev, "failed to remap I/O memory\n");
201		error = -ENXIO;
202		goto err1;
203	}
204
205	priv->input = input_allocate_device();
206	if (!priv->input) {
207		dev_err(&pdev->dev, "failed to allocate input device\n");
208		error = -ENOMEM;
209		goto err2;
210	}
211
212	input = priv->input;
213	input->evbit[0] = BIT_MASK(EV_KEY);
214
215	input->name = pdev->name;
216	input->phys = "sh-keysc-keys/input0";
217	input->dev.parent = &pdev->dev;
218
219	input->id.bustype = BUS_HOST;
220	input->id.vendor = 0x0001;
221	input->id.product = 0x0001;
222	input->id.version = 0x0100;
223
224	input->keycode = pdata->keycodes;
225	input->keycodesize = sizeof(pdata->keycodes[0]);
226	input->keycodemax = ARRAY_SIZE(pdata->keycodes);
227
228	error = request_threaded_irq(irq, NULL, sh_keysc_isr, IRQF_ONESHOT,
229				     dev_name(&pdev->dev), pdev);
230	if (error) {
231		dev_err(&pdev->dev, "failed to request IRQ\n");
232		goto err3;
233	}
234
235	for (i = 0; i < SH_KEYSC_MAXKEYS; i++)
236		__set_bit(pdata->keycodes[i], input->keybit);
237	__clear_bit(KEY_RESERVED, input->keybit);
238
239	error = input_register_device(input);
240	if (error) {
241		dev_err(&pdev->dev, "failed to register input device\n");
242		goto err4;
243	}
244
245	pm_runtime_enable(&pdev->dev);
246	pm_runtime_get_sync(&pdev->dev);
247
248	sh_keysc_write(priv, KYCR1, (sh_keysc_mode[pdata->mode].kymd << 8) |
249		       pdata->scan_timing);
250	sh_keysc_level_mode(priv, 0);
251
252	device_init_wakeup(&pdev->dev, 1);
253
254	return 0;
255
256 err4:
257	free_irq(irq, pdev);
258 err3:
259	input_free_device(input);
260 err2:
261	iounmap(priv->iomem_base);
262 err1:
263	kfree(priv);
264 err0:
265	return error;
266}
267
268static void sh_keysc_remove(struct platform_device *pdev)
269{
270	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
271
272	sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
273
274	input_unregister_device(priv->input);
275	free_irq(platform_get_irq(pdev, 0), pdev);
276	iounmap(priv->iomem_base);
277
278	pm_runtime_put_sync(&pdev->dev);
279	pm_runtime_disable(&pdev->dev);
280
281	kfree(priv);
282}
283
284static int sh_keysc_suspend(struct device *dev)
285{
286	struct platform_device *pdev = to_platform_device(dev);
287	struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
288	int irq = platform_get_irq(pdev, 0);
289	unsigned short value;
290
291	value = sh_keysc_read(priv, KYCR1);
292
293	if (device_may_wakeup(dev)) {
294		sh_keysc_write(priv, KYCR1, value | 0x80);
295		enable_irq_wake(irq);
296	} else {
297		sh_keysc_write(priv, KYCR1, value & ~0x80);
298		pm_runtime_put_sync(dev);
299	}
300
301	return 0;
302}
303
304static int sh_keysc_resume(struct device *dev)
305{
306	struct platform_device *pdev = to_platform_device(dev);
307	int irq = platform_get_irq(pdev, 0);
308
309	if (device_may_wakeup(dev))
310		disable_irq_wake(irq);
311	else
312		pm_runtime_get_sync(dev);
313
314	return 0;
315}
316
317static DEFINE_SIMPLE_DEV_PM_OPS(sh_keysc_dev_pm_ops,
318				sh_keysc_suspend, sh_keysc_resume);
319
320static struct platform_driver sh_keysc_device_driver = {
321	.probe		= sh_keysc_probe,
322	.remove_new	= sh_keysc_remove,
323	.driver		= {
324		.name	= "sh_keysc",
325		.pm	= pm_sleep_ptr(&sh_keysc_dev_pm_ops),
326	}
327};
328module_platform_driver(sh_keysc_device_driver);
329
330MODULE_AUTHOR("Magnus Damm");
331MODULE_DESCRIPTION("SuperH KEYSC Keypad Driver");
332MODULE_LICENSE("GPL");
333