summaryrefslogtreecommitdiffstats
path: root/drivers/input/keyboard/pxa930_rotary.c
blob: bcad95be73aaea053eef65168a9cdcea28a350db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/*
 * Driver for the enhanced rotary controller on pxa930 and pxa935
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>

#include <linux/platform_data/keyboard-pxa930_rotary.h>

#define SBCR	(0x04)
#define ERCR	(0x0c)

#define SBCR_ERSB	(1 << 5)

struct pxa930_rotary {
	struct input_dev	*input_dev;
	void __iomem		*mmio_base;
	int			last_ercr;

	struct pxa930_rotary_platform_data *pdata;
};

static void clear_sbcr(struct pxa930_rotary *r)
{
	uint32_t sbcr = __raw_readl(r->mmio_base + SBCR);

	__raw_writel(sbcr | SBCR_ERSB, r->mmio_base + SBCR);
	__raw_writel(sbcr & ~SBCR_ERSB, r->mmio_base + SBCR);
}

static irqreturn_t rotary_irq(int irq, void *dev_id)
{
	struct pxa930_rotary *r = dev_id;
	struct pxa930_rotary_platform_data *pdata = r->pdata;
	int ercr, delta, key;

	ercr = __raw_readl(r->mmio_base + ERCR) & 0xf;
	clear_sbcr(r);

	delta = ercr - r->last_ercr;
	if (delta == 0)
		return IRQ_HANDLED;

	r->last_ercr = ercr;

	if (pdata->up_key && pdata->down_key) {
		key = (delta > 0) ? pdata->up_key : pdata->down_key;
		input_report_key(r->input_dev, key, 1);
		input_sync(r->input_dev);
		input_report_key(r->input_dev, key, 0);
	} else
		input_report_rel(r->input_dev, pdata->rel_code, delta);

	input_sync(r->input_dev);

	return IRQ_HANDLED;
}

static int pxa930_rotary_open(struct input_dev *dev)
{
	struct pxa930_rotary *r = input_get_drvdata(dev);

	clear_sbcr(r);

	return 0;
}

static void pxa930_rotary_close(struct input_dev *dev)
{
	struct pxa930_rotary *r = input_get_drvdata(dev);

	clear_sbcr(r);
}

static int pxa930_rotary_probe(struct platform_device *pdev)
{
	struct pxa930_rotary_platform_data *pdata = pdev->dev.platform_data;
	struct pxa930_rotary *r;
	struct input_dev *input_dev;
	struct resource *res;
	int irq;
	int err;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "no irq for rotary controller\n");
		return -ENXIO;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "no I/O memory defined\n");
		return -ENXIO;
	}

	if (!pdata) {
		dev_err(&pdev->dev, "no platform data defined\n");
		return -EINVAL;
	}

	r = kzalloc(sizeof(struct pxa930_rotary), GFP_KERNEL);
	if (!r)
		return -ENOMEM;

	r->mmio_base = ioremap_nocache(res->start, resource_size(res));
	if (r->mmio_base == NULL) {
		dev_err(&pdev->dev, "failed to remap IO memory\n");
		err = -ENXIO;
		goto failed_free;
	}

	r->pdata = pdata;
	platform_set_drvdata(pdev, r);

	/* allocate and register the input device */
	input_dev = input_allocate_device();
	if (!input_dev) {
		dev_err(&pdev->dev, "failed to allocate input device\n");
		err = -ENOMEM;
		goto failed_free_io;
	}

	input_dev->name = pdev->name;
	input_dev->id.bustype = BUS_HOST;
	input_dev->open = pxa930_rotary_open;
	input_dev->close = pxa930_rotary_close;
	input_dev->dev.parent = &pdev->dev;

	if (pdata->up_key && pdata->down_key) {
		__set_bit(pdata->up_key, input_dev->keybit);
		__set_bit(pdata->down_key, input_dev->keybit);
		__set_bit(EV_KEY, input_dev->evbit);
	} else {
		__set_bit(pdata->rel_code, input_dev->relbit);
		__set_bit(EV_REL, input_dev->evbit);
	}

	r->input_dev = input_dev;
	input_set_drvdata(input_dev, r);

	err = request_irq(irq, rotary_irq, 0,
			"enhanced rotary", r);
	if (err) {
		dev_err(&pdev->dev, "failed to request IRQ\n");
		goto failed_free_input;
	}

	err = input_register_device(input_dev);
	if (err) {
		dev_err(&pdev->dev, "failed to register input device\n");
		goto failed_free_irq;
	}

	return 0;

failed_free_irq:
	free_irq(irq, r);
failed_free_input:
	input_free_device(input_dev);
failed_free_io:
	iounmap(r->mmio_base);
failed_free:
	kfree(r);
	return err;
}

static int pxa930_rotary_remove(struct platform_device *pdev)
{
	struct pxa930_rotary *r = platform_get_drvdata(pdev);

	free_irq(platform_get_irq(pdev, 0), r);
	input_unregister_device(r->input_dev);
	iounmap(r->mmio_base);
	platform_set_drvdata(pdev, NULL);
	kfree(r);

	return 0;
}

static struct platform_driver pxa930_rotary_driver = {
	.driver		= {
		.name	= "pxa930-rotary",
		.owner	= THIS_MODULE,
	},
	.probe		= pxa930_rotary_probe,
	.remove		= pxa930_rotary_remove,
};
module_platform_driver(pxa930_rotary_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Driver for PXA93x Enhanced Rotary Controller");
MODULE_AUTHOR("Yao Yong <yaoyong@marvell.com>");
OpenPOWER on IntegriCloud