![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
491 lines
11 KiB
C
491 lines
11 KiB
C
/*
|
|
* VIDEO MOTION CODECs internal API for video devices
|
|
*
|
|
* Interface for MJPEG (and maybe later MPEG/WAVELETS) codec's
|
|
* bound to a master device.
|
|
*
|
|
* (c) 2002 Wolfgang Scherr <scherr@net4you.at>
|
|
*
|
|
* $Id: videocodec.c,v 1.1.2.8 2003/03/29 07:16:04 rbultje Exp $
|
|
*
|
|
* ------------------------------------------------------------------------
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
* ------------------------------------------------------------------------
|
|
*/
|
|
|
|
#define VIDEOCODEC_VERSION "v0.2"
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/types.h>
|
|
#include <linux/slab.h>
|
|
|
|
// kernel config is here (procfs flag)
|
|
#include <linux/config.h>
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
#include <linux/proc_fs.h>
|
|
#include <asm/uaccess.h>
|
|
#endif
|
|
|
|
#include "videocodec.h"
|
|
|
|
static int debug = 0;
|
|
module_param(debug, int, 0);
|
|
MODULE_PARM_DESC(debug, "Debug level (0-4)");
|
|
|
|
#define dprintk(num, format, args...) \
|
|
do { \
|
|
if (debug >= num) \
|
|
printk(format, ##args); \
|
|
} while (0)
|
|
|
|
struct attached_list {
|
|
struct videocodec *codec;
|
|
struct attached_list *next;
|
|
};
|
|
|
|
struct codec_list {
|
|
const struct videocodec *codec;
|
|
int attached;
|
|
struct attached_list *list;
|
|
struct codec_list *next;
|
|
};
|
|
|
|
static struct codec_list *codeclist_top = NULL;
|
|
|
|
/* ================================================= */
|
|
/* function prototypes of the master/slave interface */
|
|
/* ================================================= */
|
|
|
|
struct videocodec *
|
|
videocodec_attach (struct videocodec_master *master)
|
|
{
|
|
struct codec_list *h = codeclist_top;
|
|
struct attached_list *a, *ptr;
|
|
struct videocodec *codec;
|
|
int res;
|
|
|
|
if (!master) {
|
|
dprintk(1, KERN_ERR "videocodec_attach: no data\n");
|
|
return NULL;
|
|
}
|
|
|
|
dprintk(2,
|
|
"videocodec_attach: '%s', type: %x, flags %lx, magic %lx\n",
|
|
master->name, master->type, master->flags, master->magic);
|
|
|
|
if (!h) {
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec_attach: no device available\n");
|
|
return NULL;
|
|
}
|
|
|
|
while (h) {
|
|
// attach only if the slave has at least the flags
|
|
// expected by the master
|
|
if ((master->flags & h->codec->flags) == master->flags) {
|
|
dprintk(4, "videocodec_attach: try '%s'\n",
|
|
h->codec->name);
|
|
|
|
if (!try_module_get(h->codec->owner))
|
|
return NULL;
|
|
|
|
codec =
|
|
kmalloc(sizeof(struct videocodec), GFP_KERNEL);
|
|
if (!codec) {
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec_attach: no mem\n");
|
|
goto out_module_put;
|
|
}
|
|
memcpy(codec, h->codec, sizeof(struct videocodec));
|
|
|
|
snprintf(codec->name, sizeof(codec->name),
|
|
"%s[%d]", codec->name, h->attached);
|
|
codec->master_data = master;
|
|
res = codec->setup(codec);
|
|
if (res == 0) {
|
|
dprintk(3, "videocodec_attach '%s'\n",
|
|
codec->name);
|
|
ptr = (struct attached_list *)
|
|
kmalloc(sizeof(struct attached_list),
|
|
GFP_KERNEL);
|
|
if (!ptr) {
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec_attach: no memory\n");
|
|
goto out_kfree;
|
|
}
|
|
memset(ptr, 0,
|
|
sizeof(struct attached_list));
|
|
ptr->codec = codec;
|
|
|
|
a = h->list;
|
|
if (!a) {
|
|
h->list = ptr;
|
|
dprintk(4,
|
|
"videocodec: first element\n");
|
|
} else {
|
|
while (a->next)
|
|
a = a->next; // find end
|
|
a->next = ptr;
|
|
dprintk(4,
|
|
"videocodec: in after '%s'\n",
|
|
h->codec->name);
|
|
}
|
|
|
|
h->attached += 1;
|
|
return codec;
|
|
} else {
|
|
kfree(codec);
|
|
}
|
|
}
|
|
h = h->next;
|
|
}
|
|
|
|
dprintk(1, KERN_ERR "videocodec_attach: no codec found!\n");
|
|
return NULL;
|
|
|
|
out_module_put:
|
|
module_put(h->codec->owner);
|
|
out_kfree:
|
|
kfree(codec);
|
|
return NULL;
|
|
}
|
|
|
|
int
|
|
videocodec_detach (struct videocodec *codec)
|
|
{
|
|
struct codec_list *h = codeclist_top;
|
|
struct attached_list *a, *prev;
|
|
int res;
|
|
|
|
if (!codec) {
|
|
dprintk(1, KERN_ERR "videocodec_detach: no data\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
dprintk(2,
|
|
"videocodec_detach: '%s', type: %x, flags %lx, magic %lx\n",
|
|
codec->name, codec->type, codec->flags, codec->magic);
|
|
|
|
if (!h) {
|
|
dprintk(1,
|
|
KERN_ERR "videocodec_detach: no device left...\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
while (h) {
|
|
a = h->list;
|
|
prev = NULL;
|
|
while (a) {
|
|
if (codec == a->codec) {
|
|
res = a->codec->unset(a->codec);
|
|
if (res >= 0) {
|
|
dprintk(3,
|
|
"videocodec_detach: '%s'\n",
|
|
a->codec->name);
|
|
a->codec->master_data = NULL;
|
|
} else {
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec_detach: '%s'\n",
|
|
a->codec->name);
|
|
a->codec->master_data = NULL;
|
|
}
|
|
if (prev == NULL) {
|
|
h->list = a->next;
|
|
dprintk(4,
|
|
"videocodec: delete first\n");
|
|
} else {
|
|
prev->next = a->next;
|
|
dprintk(4,
|
|
"videocodec: delete middle\n");
|
|
}
|
|
module_put(a->codec->owner);
|
|
kfree(a->codec);
|
|
kfree(a);
|
|
h->attached -= 1;
|
|
return 0;
|
|
}
|
|
prev = a;
|
|
a = a->next;
|
|
}
|
|
h = h->next;
|
|
}
|
|
|
|
dprintk(1, KERN_ERR "videocodec_detach: given codec not found!\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
int
|
|
videocodec_register (const struct videocodec *codec)
|
|
{
|
|
struct codec_list *ptr, *h = codeclist_top;
|
|
|
|
if (!codec) {
|
|
dprintk(1, KERN_ERR "videocodec_register: no data!\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
dprintk(2,
|
|
"videocodec: register '%s', type: %x, flags %lx, magic %lx\n",
|
|
codec->name, codec->type, codec->flags, codec->magic);
|
|
|
|
ptr =
|
|
(struct codec_list *) kmalloc(sizeof(struct codec_list),
|
|
GFP_KERNEL);
|
|
if (!ptr) {
|
|
dprintk(1, KERN_ERR "videocodec_register: no memory\n");
|
|
return -ENOMEM;
|
|
}
|
|
memset(ptr, 0, sizeof(struct codec_list));
|
|
ptr->codec = codec;
|
|
|
|
if (!h) {
|
|
codeclist_top = ptr;
|
|
dprintk(4, "videocodec: hooked in as first element\n");
|
|
} else {
|
|
while (h->next)
|
|
h = h->next; // find the end
|
|
h->next = ptr;
|
|
dprintk(4, "videocodec: hooked in after '%s'\n",
|
|
h->codec->name);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
videocodec_unregister (const struct videocodec *codec)
|
|
{
|
|
struct codec_list *prev = NULL, *h = codeclist_top;
|
|
|
|
if (!codec) {
|
|
dprintk(1, KERN_ERR "videocodec_unregister: no data!\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
dprintk(2,
|
|
"videocodec: unregister '%s', type: %x, flags %lx, magic %lx\n",
|
|
codec->name, codec->type, codec->flags, codec->magic);
|
|
|
|
if (!h) {
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec_unregister: no device left...\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
while (h) {
|
|
if (codec == h->codec) {
|
|
if (h->attached) {
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec: '%s' is used\n",
|
|
h->codec->name);
|
|
return -EBUSY;
|
|
}
|
|
dprintk(3, "videocodec: unregister '%s' is ok.\n",
|
|
h->codec->name);
|
|
if (prev == NULL) {
|
|
codeclist_top = h->next;
|
|
dprintk(4,
|
|
"videocodec: delete first element\n");
|
|
} else {
|
|
prev->next = h->next;
|
|
dprintk(4,
|
|
"videocodec: delete middle element\n");
|
|
}
|
|
kfree(h);
|
|
return 0;
|
|
}
|
|
prev = h;
|
|
h = h->next;
|
|
}
|
|
|
|
dprintk(1,
|
|
KERN_ERR
|
|
"videocodec_unregister: given codec not found!\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
/* ============ */
|
|
/* procfs stuff */
|
|
/* ============ */
|
|
|
|
static char *videocodec_buf = NULL;
|
|
static int videocodec_bufsize = 0;
|
|
|
|
static int
|
|
videocodec_build_table (void)
|
|
{
|
|
struct codec_list *h = codeclist_top;
|
|
struct attached_list *a;
|
|
int i = 0, size;
|
|
|
|
// sum up amount of slaves plus their attached masters
|
|
while (h) {
|
|
i += h->attached + 1;
|
|
h = h->next;
|
|
}
|
|
#define LINESIZE 100
|
|
size = LINESIZE * (i + 1);
|
|
|
|
dprintk(3, "videocodec_build table: %d entries, %d bytes\n", i,
|
|
size);
|
|
|
|
if (videocodec_buf)
|
|
kfree(videocodec_buf);
|
|
videocodec_buf = (char *) kmalloc(size, GFP_KERNEL);
|
|
|
|
i = 0;
|
|
i += scnprintf(videocodec_buf + i, size - 1,
|
|
"<S>lave or attached <M>aster name type flags magic ");
|
|
i += scnprintf(videocodec_buf + i, size -i - 1, "(connected as)\n");
|
|
|
|
h = codeclist_top;
|
|
while (h) {
|
|
if (i > (size - LINESIZE))
|
|
break; // security check
|
|
i += scnprintf(videocodec_buf + i, size -i -1,
|
|
"S %32s %04x %08lx %08lx (TEMPLATE)\n",
|
|
h->codec->name, h->codec->type,
|
|
h->codec->flags, h->codec->magic);
|
|
a = h->list;
|
|
while (a) {
|
|
if (i > (size - LINESIZE))
|
|
break; // security check
|
|
i += scnprintf(videocodec_buf + i, size -i -1,
|
|
"M %32s %04x %08lx %08lx (%s)\n",
|
|
a->codec->master_data->name,
|
|
a->codec->master_data->type,
|
|
a->codec->master_data->flags,
|
|
a->codec->master_data->magic,
|
|
a->codec->name);
|
|
a = a->next;
|
|
}
|
|
h = h->next;
|
|
}
|
|
|
|
return i;
|
|
}
|
|
|
|
//The definition:
|
|
//typedef int (read_proc_t)(char *page, char **start, off_t off,
|
|
// int count, int *eof, void *data);
|
|
|
|
static int
|
|
videocodec_info (char *buffer,
|
|
char **buffer_location,
|
|
off_t offset,
|
|
int buffer_length,
|
|
int *eof,
|
|
void *data)
|
|
{
|
|
int size;
|
|
|
|
dprintk(3, "videocodec_info: offset: %ld, len %d / size %d\n",
|
|
offset, buffer_length, videocodec_bufsize);
|
|
|
|
if (offset == 0) {
|
|
videocodec_bufsize = videocodec_build_table();
|
|
}
|
|
if ((offset < 0) || (offset >= videocodec_bufsize)) {
|
|
dprintk(4,
|
|
"videocodec_info: call delivers no result, return 0\n");
|
|
*eof = 1;
|
|
return 0;
|
|
}
|
|
|
|
if (buffer_length < (videocodec_bufsize - offset)) {
|
|
dprintk(4, "videocodec_info: %ld needed, %d got\n",
|
|
videocodec_bufsize - offset, buffer_length);
|
|
size = buffer_length;
|
|
} else {
|
|
dprintk(4, "videocodec_info: last reading of %ld bytes\n",
|
|
videocodec_bufsize - offset);
|
|
size = videocodec_bufsize - offset;
|
|
*eof = 1;
|
|
}
|
|
|
|
memcpy(buffer, videocodec_buf + offset, size);
|
|
/* doesn't work... */
|
|
/* copy_to_user(buffer, videocodec_buf+offset, size); */
|
|
/* *buffer_location = videocodec_buf+offset; */
|
|
|
|
return size;
|
|
}
|
|
#endif
|
|
|
|
/* ===================== */
|
|
/* hook in driver module */
|
|
/* ===================== */
|
|
static int __init
|
|
videocodec_init (void)
|
|
{
|
|
#ifdef CONFIG_PROC_FS
|
|
static struct proc_dir_entry *videocodec_proc_entry;
|
|
#endif
|
|
|
|
printk(KERN_INFO "Linux video codec intermediate layer: %s\n",
|
|
VIDEOCODEC_VERSION);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
videocodec_buf = NULL;
|
|
videocodec_bufsize = 0;
|
|
|
|
videocodec_proc_entry = create_proc_entry("videocodecs", 0, NULL);
|
|
if (videocodec_proc_entry) {
|
|
videocodec_proc_entry->read_proc = videocodec_info;
|
|
videocodec_proc_entry->write_proc = NULL;
|
|
videocodec_proc_entry->data = NULL;
|
|
videocodec_proc_entry->owner = THIS_MODULE;
|
|
} else {
|
|
dprintk(1, KERN_ERR "videocodec: can't init procfs.\n");
|
|
}
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static void __exit
|
|
videocodec_exit (void)
|
|
{
|
|
#ifdef CONFIG_PROC_FS
|
|
remove_proc_entry("videocodecs", NULL);
|
|
if (videocodec_buf)
|
|
kfree(videocodec_buf);
|
|
#endif
|
|
}
|
|
|
|
EXPORT_SYMBOL(videocodec_attach);
|
|
EXPORT_SYMBOL(videocodec_detach);
|
|
EXPORT_SYMBOL(videocodec_register);
|
|
EXPORT_SYMBOL(videocodec_unregister);
|
|
|
|
module_init(videocodec_init);
|
|
module_exit(videocodec_exit);
|
|
|
|
MODULE_AUTHOR("Wolfgang Scherr <scherr@net4you.at>");
|
|
MODULE_DESCRIPTION("Intermediate API module for video codecs "
|
|
VIDEOCODEC_VERSION);
|
|
MODULE_LICENSE("GPL");
|