tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Power button driver for Medfield.
3 *
4 * Copyright (C) 2010 Intel Corp
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 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/interrupt.h>
23#include <linux/slab.h>
24#include <linux/platform_device.h>
25#include <linux/input.h>
26
27#include <asm/intel_scu_ipc.h>
28
29#define DRIVER_NAME "msic_power_btn"
30
31#define MSIC_PB_STATUS 0x3f
32#define MSIC_PB_LEVEL (1 << 3) /* 1 - release, 0 - press */
33
34static irqreturn_t mfld_pb_isr(int irq, void *dev_id)
35{
36 struct input_dev *input = dev_id;
37 int ret;
38 u8 pbstat;
39
40 ret = intel_scu_ipc_ioread8(MSIC_PB_STATUS, &pbstat);
41 if (ret < 0) {
42 dev_err(input->dev.parent, "Read error %d while reading"
43 " MSIC_PB_STATUS\n", ret);
44 } else {
45 input_event(input, EV_KEY, KEY_POWER,
46 !(pbstat & MSIC_PB_LEVEL));
47 input_sync(input);
48 }
49
50 return IRQ_HANDLED;
51}
52
53static int __devinit mfld_pb_probe(struct platform_device *pdev)
54{
55 struct input_dev *input;
56 int irq = platform_get_irq(pdev, 0);
57 int error;
58
59 if (irq < 0)
60 return -EINVAL;
61
62 input = input_allocate_device();
63 if (!input) {
64 dev_err(&pdev->dev, "Input device allocation error\n");
65 return -ENOMEM;
66 }
67
68 input->name = pdev->name;
69 input->phys = "power-button/input0";
70 input->id.bustype = BUS_HOST;
71 input->dev.parent = &pdev->dev;
72
73 input_set_capability(input, EV_KEY, KEY_POWER);
74
75 error = request_threaded_irq(irq, NULL, mfld_pb_isr, 0,
76 DRIVER_NAME, input);
77 if (error) {
78 dev_err(&pdev->dev, "Unable to request irq %d for mfld power"
79 "button\n", irq);
80 goto err_free_input;
81 }
82
83 error = input_register_device(input);
84 if (error) {
85 dev_err(&pdev->dev, "Unable to register input dev, error "
86 "%d\n", error);
87 goto err_free_irq;
88 }
89
90 platform_set_drvdata(pdev, input);
91 return 0;
92
93err_free_irq:
94 free_irq(irq, input);
95err_free_input:
96 input_free_device(input);
97 return error;
98}
99
100static int __devexit mfld_pb_remove(struct platform_device *pdev)
101{
102 struct input_dev *input = platform_get_drvdata(pdev);
103 int irq = platform_get_irq(pdev, 0);
104
105 free_irq(irq, input);
106 input_unregister_device(input);
107 platform_set_drvdata(pdev, NULL);
108
109 return 0;
110}
111
112static struct platform_driver mfld_pb_driver = {
113 .driver = {
114 .name = DRIVER_NAME,
115 .owner = THIS_MODULE,
116 },
117 .probe = mfld_pb_probe,
118 .remove = __devexit_p(mfld_pb_remove),
119};
120
121static int __init mfld_pb_init(void)
122{
123 return platform_driver_register(&mfld_pb_driver);
124}
125module_init(mfld_pb_init);
126
127static void __exit mfld_pb_exit(void)
128{
129 platform_driver_unregister(&mfld_pb_driver);
130}
131module_exit(mfld_pb_exit);
132
133MODULE_AUTHOR("Hong Liu <hong.liu@intel.com>");
134MODULE_DESCRIPTION("Intel Medfield Power Button Driver");
135MODULE_LICENSE("GPL v2");
136MODULE_ALIAS("platform:" DRIVER_NAME);