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
|
/*
* Power button driver for Intel MID platforms.
*
* Copyright (C) 2010 Intel Corp
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* 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/init.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/mfd/intel_msic.h>
#include <linux/pm_wakeirq.h>
#define DRIVER_NAME "msic_power_btn"
#define MSIC_PB_LEVEL (1 << 3) /* 1 - release, 0 - press */
/*
* MSIC document ti_datasheet defines the 1st bit reg 0x21 is used to mask
* power button interrupt
*/
#define MSIC_PWRBTNM (1 << 0)
static irqreturn_t mid_pb_isr(int irq, void *dev_id)
{
struct input_dev *input = dev_id;
int ret;
u8 pbstat;
ret = intel_msic_reg_read(INTEL_MSIC_PBSTATUS, &pbstat);
dev_dbg(input->dev.parent, "PB_INT status= %d\n", pbstat);
if (ret < 0) {
dev_err(input->dev.parent, "Read error %d while reading"
" MSIC_PB_STATUS\n", ret);
} else {
input_event(input, EV_KEY, KEY_POWER,
!(pbstat & MSIC_PB_LEVEL));
input_sync(input);
}
return IRQ_HANDLED;
}
static int mid_pb_probe(struct platform_device *pdev)
{
struct input_dev *input;
int irq = platform_get_irq(pdev, 0);
int error;
if (irq < 0)
return -EINVAL;
input = devm_input_allocate_device(&pdev->dev);
if (!input)
return -ENOMEM;
input->name = pdev->name;
input->phys = "power-button/input0";
input->id.bustype = BUS_HOST;
input->dev.parent = &pdev->dev;
input_set_capability(input, EV_KEY, KEY_POWER);
error = devm_request_threaded_irq(&pdev->dev, irq, NULL, mid_pb_isr,
IRQF_ONESHOT, DRIVER_NAME, input);
if (error) {
dev_err(&pdev->dev, "Unable to request irq %d for MID power"
"button\n", irq);
return error;
}
error = input_register_device(input);
if (error) {
dev_err(&pdev->dev, "Unable to register input dev, error "
"%d\n", error);
return error;
}
platform_set_drvdata(pdev, input);
/*
* SCU firmware might send power button interrupts to IA core before
* kernel boots and doesn't get EOI from IA core. The first bit of
* MSIC reg 0x21 is kept masked, and SCU firmware doesn't send new
* power interrupt to Android kernel. Unmask the bit when probing
* power button in kernel.
* There is a very narrow race between irq handler and power button
* initialization. The race happens rarely. So we needn't worry
* about it.
*/
error = intel_msic_reg_update(INTEL_MSIC_IRQLVL1MSK, 0, MSIC_PWRBTNM);
if (error) {
dev_err(&pdev->dev, "Unable to clear power button interrupt, "
"error: %d\n", error);
return error;
}
device_init_wakeup(&pdev->dev, true);
dev_pm_set_wake_irq(&pdev->dev, irq);
return 0;
}
static int mid_pb_remove(struct platform_device *pdev)
{
dev_pm_clear_wake_irq(&pdev->dev);
device_init_wakeup(&pdev->dev, false);
return 0;
}
static struct platform_driver mid_pb_driver = {
.driver = {
.name = DRIVER_NAME,
},
.probe = mid_pb_probe,
.remove = mid_pb_remove,
};
module_platform_driver(mid_pb_driver);
MODULE_AUTHOR("Hong Liu <hong.liu@intel.com>");
MODULE_DESCRIPTION("Intel MID Power Button Driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRIVER_NAME);
|
