aboutsummaryrefslogtreecommitdiff
path: root/drivers/input/misc/wm831x-on.c
blob: 1b44de265a0ad454a82a2282001f8be75a7875d7 (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
/**
 * wm831x-on.c - WM831X ON pin driver
 *
 * Copyright (C) 2009 Wolfson Microelectronics plc
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License. See the file "COPYING" in the main directory of this
 * archive for more details.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/workqueue.h>
#include <linux/mfd/wm831x/core.h>

struct wm831x_on {
	struct input_dev *dev;
	struct delayed_work work;
	struct wm831x *wm831x;
};

/*
 * The chip gives us an interrupt when the ON pin is asserted but we
 * then need to poll to see when the pin is deasserted.
 */
static void wm831x_poll_on(struct work_struct *work)
{
	struct wm831x_on *wm831x_on = container_of(work, struct wm831x_on,
						   work.work);
	struct wm831x *wm831x = wm831x_on->wm831x;
	int poll, ret;

	ret = wm831x_reg_read(wm831x, WM831X_ON_PIN_CONTROL);
	if (ret >= 0) {
		poll = !(ret & WM831X_ON_PIN_STS);

		input_report_key(wm831x_on->dev, KEY_POWER, poll);
		input_sync(wm831x_on->dev);
	} else {
		dev_err(wm831x->dev, "Failed to read ON status: %d\n", ret);
		poll = 1;
	}

	if (poll)
		schedule_delayed_work(&wm831x_on->work, 100);
}

static irqreturn_t wm831x_on_irq(int irq, void *data)
{
	struct wm831x_on *wm831x_on = data;

	schedule_delayed_work(&wm831x_on->work, 0);

	return IRQ_HANDLED;
}

static int wm831x_on_probe(struct platform_device *pdev)
{
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_on *wm831x_on;
	int irq = wm831x_irq(wm831x, platform_get_irq(pdev, 0));
	int ret;

	wm831x_on = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_on),
				 GFP_KERNEL);
	if (!wm831x_on) {
		dev_err(&pdev->dev, "Can't allocate data\n");
		return -ENOMEM;
	}

	wm831x_on->wm831x = wm831x;
	INIT_DELAYED_WORK(&wm831x_on->work, wm831x_poll_on);

	wm831x_on->dev = devm_input_allocate_device(&pdev->dev);
	if (!wm831x_on->dev) {
		dev_err(&pdev->dev, "Can't allocate input dev\n");
		ret = -ENOMEM;
		goto err;
	}

	wm831x_on->dev->evbit[0] = BIT_MASK(EV_KEY);
	wm831x_on->dev->keybit[BIT_WORD(KEY_POWER)] = BIT_MASK(KEY_POWER);
	wm831x_on->dev->name = "wm831x_on";
	wm831x_on->dev->phys = "wm831x_on/input0";
	wm831x_on->dev->dev.parent = &pdev->dev;

	ret = request_threaded_irq(irq, NULL, wm831x_on_irq,
				   IRQF_TRIGGER_RISING | IRQF_ONESHOT,
				   "wm831x_on",
				   wm831x_on);
	if (ret < 0) {
		dev_err(&pdev->dev, "Unable to request IRQ: %d\n", ret);
		goto err_input_dev;
	}
	ret = input_register_device(wm831x_on->dev);
	if (ret) {
		dev_dbg(&pdev->dev, "Can't register input device: %d\n", ret);
		goto err_irq;
	}

	platform_set_drvdata(pdev, wm831x_on);

	return 0;

err_irq:
	free_irq(irq, wm831x_on);
err_input_dev:
err:
	return ret;
}

static int wm831x_on_remove(struct platform_device *pdev)
{
	struct wm831x_on *wm831x_on = platform_get_drvdata(pdev);
	int irq = platform_get_irq(pdev, 0);

	free_irq(irq, wm831x_on);
	cancel_delayed_work_sync(&wm831x_on->work);

	return 0;
}

static struct platform_driver wm831x_on_driver = {
	.probe		= wm831x_on_probe,
	.remove		= wm831x_on_remove,
	.driver		= {
		.name	= "wm831x-on",
	},
};
module_platform_driver(wm831x_on_driver);

MODULE_ALIAS("platform:wm831x-on");
MODULE_DESCRIPTION("WM831x ON pin");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");