Merge branch 'linus' into timers/nohz
[linux-2.6] / arch / sh / drivers / push-switch.c
1 /*
2  * Generic push-switch framework
3  *
4  * Copyright (C) 2006  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <asm/push-switch.h>
15
16 #define DRV_NAME "push-switch"
17 #define DRV_VERSION "0.1.1"
18
19 static ssize_t switch_show(struct device *dev,
20                            struct device_attribute *attr,
21                            char *buf)
22 {
23         struct push_switch_platform_info *psw_info = dev->platform_data;
24         return sprintf(buf, "%s\n", psw_info->name);
25 }
26 static DEVICE_ATTR(switch, S_IRUGO, switch_show, NULL);
27
28 static void switch_timer(unsigned long data)
29 {
30         struct push_switch *psw = (struct push_switch *)data;
31
32         schedule_work(&psw->work);
33 }
34
35 static void switch_work_handler(struct work_struct *work)
36 {
37         struct push_switch *psw = container_of(work, struct push_switch, work);
38         struct platform_device *pdev = psw->pdev;
39
40         psw->state = 0;
41
42         kobject_uevent(&pdev->dev.kobj, KOBJ_CHANGE);
43 }
44
45 static int switch_drv_probe(struct platform_device *pdev)
46 {
47         struct push_switch_platform_info *psw_info;
48         struct push_switch *psw;
49         int ret, irq;
50
51         psw = kzalloc(sizeof(struct push_switch), GFP_KERNEL);
52         if (unlikely(!psw))
53                 return -ENOMEM;
54
55         irq = platform_get_irq(pdev, 0);
56         if (unlikely(irq < 0)) {
57                 ret = -ENODEV;
58                 goto err;
59         }
60
61         psw_info = pdev->dev.platform_data;
62         BUG_ON(!psw_info);
63
64         ret = request_irq(irq, psw_info->irq_handler,
65                           IRQF_DISABLED | psw_info->irq_flags,
66                           psw_info->name ? psw_info->name : DRV_NAME, pdev);
67         if (unlikely(ret < 0))
68                 goto err;
69
70         if (psw_info->name) {
71                 ret = device_create_file(&pdev->dev, &dev_attr_switch);
72                 if (unlikely(ret)) {
73                         dev_err(&pdev->dev, "Failed creating device attrs\n");
74                         ret = -EINVAL;
75                         goto err_irq;
76                 }
77         }
78
79         INIT_WORK(&psw->work, switch_work_handler);
80         init_timer(&psw->debounce);
81
82         psw->debounce.function = switch_timer;
83         psw->debounce.data = (unsigned long)psw;
84
85         /* Workqueue API brain-damage */
86         psw->pdev = pdev;
87
88         platform_set_drvdata(pdev, psw);
89
90         return 0;
91
92 err_irq:
93         free_irq(irq, pdev);
94 err:
95         kfree(psw);
96         return ret;
97 }
98
99 static int switch_drv_remove(struct platform_device *pdev)
100 {
101         struct push_switch *psw = platform_get_drvdata(pdev);
102         struct push_switch_platform_info *psw_info = pdev->dev.platform_data;
103         int irq = platform_get_irq(pdev, 0);
104
105         if (psw_info->name)
106                 device_remove_file(&pdev->dev, &dev_attr_switch);
107
108         platform_set_drvdata(pdev, NULL);
109         flush_scheduled_work();
110         del_timer_sync(&psw->debounce);
111         free_irq(irq, pdev);
112
113         kfree(psw);
114
115         return 0;
116 }
117
118 static struct platform_driver switch_driver = {
119         .probe          = switch_drv_probe,
120         .remove         = switch_drv_remove,
121         .driver         = {
122                 .name   = DRV_NAME,
123         },
124 };
125
126 static int __init switch_init(void)
127 {
128         printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
129         return platform_driver_register(&switch_driver);
130 }
131
132 static void __exit switch_exit(void)
133 {
134         platform_driver_unregister(&switch_driver);
135 }
136 module_init(switch_init);
137 module_exit(switch_exit);
138
139 MODULE_VERSION(DRV_VERSION);
140 MODULE_AUTHOR("Paul Mundt");
141 MODULE_LICENSE("GPL v2");