tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/**
2 * wm831x-on.c - WM831X ON pin driver
3 *
4 * Copyright (C) 2009 Wolfson Microelectronics plc
5 *
6 * This file is subject to the terms and conditions of the GNU General
7 * Public License. See the file "COPYING" in the main directory of this
8 * archive for more details.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/errno.h>
24#include <linux/input.h>
25#include <linux/interrupt.h>
26#include <linux/platform_device.h>
27#include <linux/workqueue.h>
28#include <linux/mfd/wm831x/core.h>
29
30struct wm831x_on {
31 struct input_dev *dev;
32 struct delayed_work work;
33 struct wm831x *wm831x;
34};
35
36/*
37 * The chip gives us an interrupt when the ON pin is asserted but we
38 * then need to poll to see when the pin is deasserted.
39 */
40static void wm831x_poll_on(struct work_struct *work)
41{
42 struct wm831x_on *wm831x_on = container_of(work, struct wm831x_on,
43 work.work);
44 struct wm831x *wm831x = wm831x_on->wm831x;
45 int poll, ret;
46
47 ret = wm831x_reg_read(wm831x, WM831X_ON_PIN_CONTROL);
48 if (ret >= 0) {
49 poll = !(ret & WM831X_ON_PIN_STS);
50
51 input_report_key(wm831x_on->dev, KEY_POWER, poll);
52 input_sync(wm831x_on->dev);
53 } else {
54 dev_err(wm831x->dev, "Failed to read ON status: %d\n", ret);
55 poll = 1;
56 }
57
58 if (poll)
59 schedule_delayed_work(&wm831x_on->work, 100);
60}
61
62static irqreturn_t wm831x_on_irq(int irq, void *data)
63{
64 struct wm831x_on *wm831x_on = data;
65
66 schedule_delayed_work(&wm831x_on->work, 0);
67
68 return IRQ_HANDLED;
69}
70
71static int __devinit wm831x_on_probe(struct platform_device *pdev)
72{
73 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
74 struct wm831x_on *wm831x_on;
75 int irq = platform_get_irq(pdev, 0);
76 int ret;
77
78 wm831x_on = kzalloc(sizeof(struct wm831x_on), GFP_KERNEL);
79 if (!wm831x_on) {
80 dev_err(&pdev->dev, "Can't allocate data\n");
81 return -ENOMEM;
82 }
83
84 wm831x_on->wm831x = wm831x;
85 INIT_DELAYED_WORK(&wm831x_on->work, wm831x_poll_on);
86
87 wm831x_on->dev = input_allocate_device();
88 if (!wm831x_on->dev) {
89 dev_err(&pdev->dev, "Can't allocate input dev\n");
90 ret = -ENOMEM;
91 goto err;
92 }
93
94 wm831x_on->dev->evbit[0] = BIT_MASK(EV_KEY);
95 wm831x_on->dev->keybit[BIT_WORD(KEY_POWER)] = BIT_MASK(KEY_POWER);
96 wm831x_on->dev->name = "wm831x_on";
97 wm831x_on->dev->phys = "wm831x_on/input0";
98 wm831x_on->dev->dev.parent = &pdev->dev;
99
100 ret = wm831x_request_irq(wm831x, irq, wm831x_on_irq,
101 IRQF_TRIGGER_RISING, "wm831x_on", wm831x_on);
102 if (ret < 0) {
103 dev_err(&pdev->dev, "Unable to request IRQ: %d\n", ret);
104 goto err_input_dev;
105 }
106 ret = input_register_device(wm831x_on->dev);
107 if (ret) {
108 dev_dbg(&pdev->dev, "Can't register input device: %d\n", ret);
109 goto err_irq;
110 }
111
112 platform_set_drvdata(pdev, wm831x_on);
113
114 return 0;
115
116err_irq:
117 wm831x_free_irq(wm831x, irq, NULL);
118err_input_dev:
119 input_free_device(wm831x_on->dev);
120err:
121 kfree(wm831x_on);
122 return ret;
123}
124
125static int __devexit wm831x_on_remove(struct platform_device *pdev)
126{
127 struct wm831x_on *wm831x_on = platform_get_drvdata(pdev);
128 int irq = platform_get_irq(pdev, 0);
129
130 wm831x_free_irq(wm831x_on->wm831x, irq, wm831x_on);
131 cancel_delayed_work_sync(&wm831x_on->work);
132 input_unregister_device(wm831x_on->dev);
133 kfree(wm831x_on);
134
135 return 0;
136}
137
138static struct platform_driver wm831x_on_driver = {
139 .probe = wm831x_on_probe,
140 .remove = __devexit_p(wm831x_on_remove),
141 .driver = {
142 .name = "wm831x-on",
143 .owner = THIS_MODULE,
144 },
145};
146
147static int __init wm831x_on_init(void)
148{
149 return platform_driver_register(&wm831x_on_driver);
150}
151module_init(wm831x_on_init);
152
153static void __exit wm831x_on_exit(void)
154{
155 platform_driver_unregister(&wm831x_on_driver);
156}
157module_exit(wm831x_on_exit);
158
159MODULE_ALIAS("platform:wm831x-on");
160MODULE_DESCRIPTION("WM831x ON pin");
161MODULE_LICENSE("GPL");
162MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
163