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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/*
* LIRC base driver
*
* by Artur Lipowski <alipowski@interia.pl>
* This code is licensed under GNU GPL
*
*/
#ifndef _LINUX_LIRC_DEV_H
#define _LINUX_LIRC_DEV_H
#define MAX_IRCTL_DEVICES 4
#define BUFLEN 16
#define mod(n, div) ((n) % (div))
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/ioctl.h>
#include <linux/poll.h>
#include <linux/kfifo.h>
#include <media/lirc.h>
struct lirc_buffer {
wait_queue_head_t wait_poll;
spinlock_t fifo_lock;
unsigned int chunk_size;
unsigned int size; /* in chunks */
/* Using chunks instead of bytes pretends to simplify boundary checking
* And should allow for some performance fine tunning later */
struct kfifo fifo;
u8 fifo_initialized;
};
static inline void lirc_buffer_clear(struct lirc_buffer *buf)
{
unsigned long flags;
if (buf->fifo_initialized) {
spin_lock_irqsave(&buf->fifo_lock, flags);
kfifo_reset(&buf->fifo);
spin_unlock_irqrestore(&buf->fifo_lock, flags);
} else
WARN(1, "calling %s on an uninitialized lirc_buffer\n",
__func__);
}
static inline int lirc_buffer_init(struct lirc_buffer *buf,
unsigned int chunk_size,
unsigned int size)
{
int ret;
init_waitqueue_head(&buf->wait_poll);
spin_lock_init(&buf->fifo_lock);
buf->chunk_size = chunk_size;
buf->size = size;
ret = kfifo_alloc(&buf->fifo, size * chunk_size, GFP_KERNEL);
if (ret == 0)
buf->fifo_initialized = 1;
return ret;
}
static inline void lirc_buffer_free(struct lirc_buffer *buf)
{
if (buf->fifo_initialized) {
kfifo_free(&buf->fifo);
buf->fifo_initialized = 0;
} else
WARN(1, "calling %s on an uninitialized lirc_buffer\n",
__func__);
}
static inline int lirc_buffer_len(struct lirc_buffer *buf)
{
int len;
unsigned long flags;
spin_lock_irqsave(&buf->fifo_lock, flags);
len = kfifo_len(&buf->fifo);
spin_unlock_irqrestore(&buf->fifo_lock, flags);
return len;
}
static inline int lirc_buffer_full(struct lirc_buffer *buf)
{
return lirc_buffer_len(buf) == buf->size * buf->chunk_size;
}
static inline int lirc_buffer_empty(struct lirc_buffer *buf)
{
return !lirc_buffer_len(buf);
}
static inline int lirc_buffer_available(struct lirc_buffer *buf)
{
return buf->size - (lirc_buffer_len(buf) / buf->chunk_size);
}
static inline unsigned int lirc_buffer_read(struct lirc_buffer *buf,
unsigned char *dest)
{
unsigned int ret = 0;
if (lirc_buffer_len(buf) >= buf->chunk_size)
ret = kfifo_out_locked(&buf->fifo, dest, buf->chunk_size,
&buf->fifo_lock);
return ret;
}
static inline unsigned int lirc_buffer_write(struct lirc_buffer *buf,
unsigned char *orig)
{
unsigned int ret;
ret = kfifo_in_locked(&buf->fifo, orig, buf->chunk_size,
&buf->fifo_lock);
return ret;
}
struct lirc_driver {
char name[40];
int minor;
__u32 code_length;
unsigned int buffer_size; /* in chunks holding one code each */
int sample_rate;
__u32 features;
unsigned int chunk_size;
void *data;
int min_timeout;
int max_timeout;
int (*add_to_buf) (void *data, struct lirc_buffer *buf);
struct lirc_buffer *rbuf;
int (*set_use_inc) (void *data);
void (*set_use_dec) (void *data);
const struct file_operations *fops;
struct device *dev;
struct module *owner;
};
/* name:
* this string will be used for logs
*
* minor:
* indicates minor device (/dev/lirc) number for registered driver
* if caller fills it with negative value, then the first free minor
* number will be used (if available)
*
* code_length:
* length of the remote control key code expressed in bits
*
* sample_rate:
*
* data:
* it may point to any driver data and this pointer will be passed to
* all callback functions
*
* add_to_buf:
* add_to_buf will be called after specified period of the time or
* triggered by the external event, this behavior depends on value of
* the sample_rate this function will be called in user context. This
* routine should return 0 if data was added to the buffer and
* -ENODATA if none was available. This should add some number of bits
* evenly divisible by code_length to the buffer
*
* rbuf:
* if not NULL, it will be used as a read buffer, you will have to
* write to the buffer by other means, like irq's (see also
* lirc_serial.c).
*
* set_use_inc:
* set_use_inc will be called after device is opened
*
* set_use_dec:
* set_use_dec will be called after device is closed
*
* fops:
* file_operations for drivers which don't fit the current driver model.
*
* Some ioctl's can be directly handled by lirc_dev if the driver's
* ioctl function is NULL or if it returns -ENOIOCTLCMD (see also
* lirc_serial.c).
*
* owner:
* the module owning this struct
*
*/
/* following functions can be called ONLY from user context
*
* returns negative value on error or minor number
* of the registered device if success
* contents of the structure pointed by p is copied
*/
extern int lirc_register_driver(struct lirc_driver *d);
/* returns negative value on error or 0 if success
*/
extern int lirc_unregister_driver(int minor);
/* Returns the private data stored in the lirc_driver
* associated with the given device file pointer.
*/
void *lirc_get_pdata(struct file *file);
/* default file operations
* used by drivers if they override only some operations
*/
int lirc_dev_fop_open(struct inode *inode, struct file *file);
int lirc_dev_fop_close(struct inode *inode, struct file *file);
unsigned int lirc_dev_fop_poll(struct file *file, poll_table *wait);
long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
ssize_t lirc_dev_fop_read(struct file *file, char *buffer, size_t length,
loff_t *ppos);
ssize_t lirc_dev_fop_write(struct file *file, const char *buffer, size_t length,
loff_t *ppos);
#endif
|
