summaryrefslogtreecommitdiffstats
path: root/arch/sh/drivers/push-switch.c
blob: 762bc561991058c82cc2e19c90d87c1fa49fb70c (plain)
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
/*
 * Generic push-switch framework
 *
 * Copyright (C) 2006  Paul Mundt
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <asm/push-switch.h>

#define DRV_NAME "push-switch"
#define DRV_VERSION "0.1.1"

static ssize_t switch_show(struct device *dev,
			   struct device_attribute *attr,
			   char *buf)
{
	struct push_switch_platform_info *psw_info = dev->platform_data;
	return sprintf(buf, "%s\n", psw_info->name);
}
static DEVICE_ATTR_RO(switch);

static void switch_timer(struct timer_list *t)
{
	struct push_switch *psw = from_timer(psw, t, debounce);

	schedule_work(&psw->work);
}

static void switch_work_handler(struct work_struct *work)
{
	struct push_switch *psw = container_of(work, struct push_switch, work);
	struct platform_device *pdev = psw->pdev;

	psw->state = 0;

	kobject_uevent(&pdev->dev.kobj, KOBJ_CHANGE);
}

static int switch_drv_probe(struct platform_device *pdev)
{
	struct push_switch_platform_info *psw_info;
	struct push_switch *psw;
	int ret, irq;

	psw = kzalloc(sizeof(struct push_switch), GFP_KERNEL);
	if (unlikely(!psw))
		return -ENOMEM;

	irq = platform_get_irq(pdev, 0);
	if (unlikely(irq < 0)) {
		ret = -ENODEV;
		goto err;
	}

	psw_info = pdev->dev.platform_data;
	BUG_ON(!psw_info);

	ret = request_irq(irq, psw_info->irq_handler,
			  psw_info->irq_flags,
			  psw_info->name ? psw_info->name : DRV_NAME, pdev);
	if (unlikely(ret < 0))
		goto err;

	if (psw_info->name) {
		ret = device_create_file(&pdev->dev, &dev_attr_switch);
		if (unlikely(ret)) {
			dev_err(&pdev->dev, "Failed creating device attrs\n");
			ret = -EINVAL;
			goto err_irq;
		}
	}

	INIT_WORK(&psw->work, switch_work_handler);
	timer_setup(&psw->debounce, switch_timer, 0);

	/* Workqueue API brain-damage */
	psw->pdev = pdev;

	platform_set_drvdata(pdev, psw);

	return 0;

err_irq:
	free_irq(irq, pdev);
err:
	kfree(psw);
	return ret;
}

static int switch_drv_remove(struct platform_device *pdev)
{
	struct push_switch *psw = platform_get_drvdata(pdev);
	struct push_switch_platform_info *psw_info = pdev->dev.platform_data;
	int irq = platform_get_irq(pdev, 0);

	if (psw_info->name)
		device_remove_file(&pdev->dev, &dev_attr_switch);

	platform_set_drvdata(pdev, NULL);
	flush_work(&psw->work);
	del_timer_sync(&psw->debounce);
	free_irq(irq, pdev);

	kfree(psw);

	return 0;
}

static struct platform_driver switch_driver = {
	.probe		= switch_drv_probe,
	.remove		= switch_drv_remove,
	.driver		= {
		.name	= DRV_NAME,
	},
};

static int __init switch_init(void)
{
	printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
	return platform_driver_register(&switch_driver);
}

static void __exit switch_exit(void)
{
	platform_driver_unregister(&switch_driver);
}
module_init(switch_init);
module_exit(switch_exit);

MODULE_VERSION(DRV_VERSION);
MODULE_AUTHOR("Paul Mundt");
MODULE_LICENSE("GPL v2");