misc: MAX1749 vibrator motor driver
[linux-2.6.git] / drivers / misc / max1749.c
1 /*
2  * drivers/misc/max1749.c
3  *
4  * Driver for MAX1749, vibrator motor driver.
5  *
6  * Copyright (c) 2011, NVIDIA Corporation.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but WITHOUT
14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16  * more details.
17  *
18  * You should have received a copy of the GNU General Public License along
19  * with this program; if not, write to the Free Software Foundation, Inc.,
20  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
21  */
22
23 #include <linux/regulator/consumer.h>
24 #include <linux/kernel.h>
25 #include <linux/platform_device.h>
26 #include <linux/err.h>
27 #include <linux/hrtimer.h>
28 #include <linux/delay.h>
29
30 #include <../staging/android/timed_output.h>
31
32 static struct regulator *regulator;
33 static int timeout;
34
35 static void vibrator_start(void)
36 {
37         regulator_enable(regulator);
38 }
39
40 static void vibrator_stop(void)
41 {
42         int ret;
43
44         ret = regulator_is_enabled(regulator);
45         if (ret > 0)
46                 regulator_disable(regulator);
47 }
48
49 /*
50  * Timeout value can be changed from sysfs entry
51  * created by timed_output_dev.
52  * echo 100 > /sys/class/timed_output/vibrator/enable
53  */
54 static void vibrator_enable(struct timed_output_dev *dev, int value)
55 {
56         timeout = value;
57         if (!regulator)
58                 return;
59
60         if (value) {
61                 vibrator_start();
62                 msleep(value);
63                 vibrator_stop();
64         } else {
65                 vibrator_stop();
66         }
67 }
68
69 /*
70  * Timeout value can be read from sysfs entry
71  * created by timed_output_dev.
72  * cat /sys/class/timed_output/vibrator/enable
73  */
74 static int vibrator_get_time(struct timed_output_dev *dev)
75 {
76         return timeout;
77 }
78
79 static struct timed_output_dev vibrator_dev = {
80         .name           = "vibrator",
81         .get_time       = vibrator_get_time,
82         .enable         = vibrator_enable,
83 };
84
85 static int __init vibrator_init(void)
86 {
87         int status;
88
89         regulator = regulator_get(NULL, "vdd_vbrtr");
90         if (IS_ERR_OR_NULL(regulator)) {
91                 pr_err("vibrator_init:Couldn't get regulator vdd_vbrtr\n");
92                 regulator = NULL;
93                 return PTR_ERR(regulator);
94         }
95
96         status = timed_output_dev_register(&vibrator_dev);
97
98         if (status) {
99                 regulator_put(regulator);
100                 regulator = NULL;
101         }
102         return status;
103 }
104
105 static void __exit vibrator_exit(void)
106 {
107         if (regulator) {
108                 timed_output_dev_unregister(&vibrator_dev);
109                 regulator_put(regulator);
110                 regulator = NULL;
111         }
112 }
113
114 MODULE_DESCRIPTION("timed output vibrator device");
115 MODULE_AUTHOR("GPL");
116
117 module_init(vibrator_init);
118 module_exit(vibrator_exit);