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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#include <linux/mfd/intel_msic.h>
27#include <linux/pm_wakeirq.h>
28
29#define DRIVER_NAME "msic_power_btn"
30
31#define MSIC_PB_LEVEL (1 << 3) /* 1 - release, 0 - press */
32
33/*
34 * MSIC document ti_datasheet defines the 1st bit reg 0x21 is used to mask
35 * power button interrupt
36 */
37#define MSIC_PWRBTNM (1 << 0)
38
39static irqreturn_t mfld_pb_isr(int irq, void *dev_id)
40{
41 struct input_dev *input = dev_id;
42 int ret;
43 u8 pbstat;
44
45 ret = intel_msic_reg_read(INTEL_MSIC_PBSTATUS, &pbstat);
46 dev_dbg(input->dev.parent, "PB_INT status= %d\n", pbstat);
47
48 if (ret < 0) {
49 dev_err(input->dev.parent, "Read error %d while reading"
50 " MSIC_PB_STATUS\n", ret);
51 } else {
52 input_event(input, EV_KEY, KEY_POWER,
53 !(pbstat & MSIC_PB_LEVEL));
54 input_sync(input);
55 }
56
57 return IRQ_HANDLED;
58}
59
60static int mfld_pb_probe(struct platform_device *pdev)
61{
62 struct input_dev *input;
63 int irq = platform_get_irq(pdev, 0);
64 int error;
65
66 if (irq < 0)
67 return -EINVAL;
68
69 input = input_allocate_device();
70 if (!input)
71 return -ENOMEM;
72
73 input->name = pdev->name;
74 input->phys = "power-button/input0";
75 input->id.bustype = BUS_HOST;
76 input->dev.parent = &pdev->dev;
77
78 input_set_capability(input, EV_KEY, KEY_POWER);
79
80 error = request_threaded_irq(irq, NULL, mfld_pb_isr, 0,
81 DRIVER_NAME, input);
82 if (error) {
83 dev_err(&pdev->dev, "Unable to request irq %d for mfld power"
84 "button\n", irq);
85 goto err_free_input;
86 }
87
88 device_init_wakeup(&pdev->dev, true);
89 dev_pm_set_wake_irq(&pdev->dev, irq);
90
91 error = input_register_device(input);
92 if (error) {
93 dev_err(&pdev->dev, "Unable to register input dev, error "
94 "%d\n", error);
95 goto err_free_irq;
96 }
97
98 platform_set_drvdata(pdev, input);
99
100 /*
101 * SCU firmware might send power button interrupts to IA core before
102 * kernel boots and doesn't get EOI from IA core. The first bit of
103 * MSIC reg 0x21 is kept masked, and SCU firmware doesn't send new
104 * power interrupt to Android kernel. Unmask the bit when probing
105 * power button in kernel.
106 * There is a very narrow race between irq handler and power button
107 * initialization. The race happens rarely. So we needn't worry
108 * about it.
109 */
110 error = intel_msic_reg_update(INTEL_MSIC_IRQLVL1MSK, 0, MSIC_PWRBTNM);
111 if (error) {
112 dev_err(&pdev->dev, "Unable to clear power button interrupt, "
113 "error: %d\n", error);
114 goto err_free_irq;
115 }
116
117 return 0;
118
119err_free_irq:
120 free_irq(irq, input);
121err_free_input:
122 input_free_device(input);
123 return error;
124}
125
126static int mfld_pb_remove(struct platform_device *pdev)
127{
128 struct input_dev *input = platform_get_drvdata(pdev);
129 int irq = platform_get_irq(pdev, 0);
130
131 dev_pm_clear_wake_irq(&pdev->dev);
132 device_init_wakeup(&pdev->dev, false);
133 free_irq(irq, input);
134 input_unregister_device(input);
135
136 return 0;
137}
138
139static struct platform_driver mfld_pb_driver = {
140 .driver = {
141 .name = DRIVER_NAME,
142 },
143 .probe = mfld_pb_probe,
144 .remove = mfld_pb_remove,
145};
146
147module_platform_driver(mfld_pb_driver);
148
149MODULE_AUTHOR("Hong Liu <hong.liu@intel.com>");
150MODULE_DESCRIPTION("Intel Medfield Power Button Driver");
151MODULE_LICENSE("GPL v2");
152MODULE_ALIAS("platform:" DRIVER_NAME);
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);