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20#include <linux/compiler.h>
21#include <linux/init.h>
22#include <linux/module.h>
23#include <linux/sched.h>
24#include <linux/wait.h>
25#include <linux/poll.h>
26#include <linux/interrupt.h>
27#include <linux/platform_device.h>
28#include <linux/miscdevice.h>
29
30#include "excite_iodev.h"
31
32
33
34static const struct resource *iodev_get_resource(struct platform_device *, const char *, unsigned int);
35static int __init iodev_probe(struct device *);
36static int __exit iodev_remove(struct device *);
37static int iodev_open(struct inode *, struct file *);
38static int iodev_release(struct inode *, struct file *);
39static ssize_t iodev_read(struct file *, char __user *, size_t s, loff_t *);
40static unsigned int iodev_poll(struct file *, struct poll_table_struct *);
41static irqreturn_t iodev_irqhdl(int, void *);
42
43
44
45static const char iodev_name[] = "iodev";
46static unsigned int iodev_irq;
47static DECLARE_WAIT_QUEUE_HEAD(wq);
48
49
50
51static struct file_operations fops =
52{
53 .owner = THIS_MODULE,
54 .open = iodev_open,
55 .release = iodev_release,
56 .read = iodev_read,
57 .poll = iodev_poll
58};
59
60static struct miscdevice miscdev =
61{
62 .minor = MISC_DYNAMIC_MINOR,
63 .name = iodev_name,
64 .fops = &fops
65};
66
67static struct device_driver iodev_driver =
68{
69 .name = (char *) iodev_name,
70 .bus = &platform_bus_type,
71 .owner = THIS_MODULE,
72 .probe = iodev_probe,
73 .remove = __exit_p(iodev_remove)
74};
75
76
77
78static const struct resource *
79iodev_get_resource(struct platform_device *pdv, const char *name,
80 unsigned int type)
81{
82 char buf[80];
83 if (snprintf(buf, sizeof buf, "%s_0", name) >= sizeof buf)
84 return NULL;
85 return platform_get_resource_byname(pdv, type, buf);
86}
87
88
89
90
91static int __init iodev_probe(struct device *dev)
92{
93 struct platform_device * const pdv = to_platform_device(dev);
94 const struct resource * const ri =
95 iodev_get_resource(pdv, IODEV_RESOURCE_IRQ, IORESOURCE_IRQ);
96
97 if (unlikely(!ri))
98 return -ENXIO;
99
100 iodev_irq = ri->start;
101 return misc_register(&miscdev);
102}
103
104
105
106static int __exit iodev_remove(struct device *dev)
107{
108 return misc_deregister(&miscdev);
109}
110
111static int iodev_open(struct inode *i, struct file *f)
112{
113 return request_irq(iodev_irq, iodev_irqhdl, IRQF_DISABLED,
114 iodev_name, &miscdev);
115}
116
117static int iodev_release(struct inode *i, struct file *f)
118{
119 free_irq(iodev_irq, &miscdev);
120 return 0;
121}
122
123
124
125
126static ssize_t
127iodev_read(struct file *f, char __user *d, size_t s, loff_t *o)
128{
129 ssize_t ret;
130 DEFINE_WAIT(w);
131
132 prepare_to_wait(&wq, &w, TASK_INTERRUPTIBLE);
133 if (!signal_pending(current))
134 schedule();
135 ret = signal_pending(current) ? -ERESTARTSYS : 0;
136 finish_wait(&wq, &w);
137 return ret;
138}
139
140
141static unsigned int iodev_poll(struct file *f, struct poll_table_struct *p)
142{
143 poll_wait(f, &wq, p);
144 return POLLOUT | POLLWRNORM;
145}
146
147static irqreturn_t iodev_irqhdl(int irq, void *ctxt)
148{
149 wake_up(&wq);
150
151 return IRQ_HANDLED;
152}
153
154static int __init iodev_init_module(void)
155{
156 return driver_register(&iodev_driver);
157}
158
159
160
161static void __exit iodev_cleanup_module(void)
162{
163 driver_unregister(&iodev_driver);
164}
165
166module_init(iodev_init_module);
167module_exit(iodev_cleanup_module);
168
169
170
171MODULE_AUTHOR("Thomas Koeller <thomas.koeller@baslerweb.com>");
172MODULE_DESCRIPTION("Basler eXcite i/o interrupt handler");
173MODULE_VERSION("0.0");
174MODULE_LICENSE("GPL");
175
