409 lines
		
	
	
		
			9.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			409 lines
		
	
	
		
			9.1 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)
 | 
						|
 | 
						|
#ifdef CONFIG_PROC_FS
 | 
						|
#include <linux/proc_fs.h>
 | 
						|
#include <linux/seq_file.h>
 | 
						|
#include <asm/uaccess.h>
 | 
						|
#endif
 | 
						|
 | 
						|
#include "videocodec.h"
 | 
						|
 | 
						|
static int debug;
 | 
						|
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', flags %lx, magic %lx\n",
 | 
						|
		master->name, 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 = kzalloc(sizeof(struct attached_list), GFP_KERNEL);
 | 
						|
				if (!ptr) {
 | 
						|
					dprintk(1,
 | 
						|
						KERN_ERR
 | 
						|
						"videocodec_attach: no memory\n");
 | 
						|
					goto out_kfree;
 | 
						|
				}
 | 
						|
				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 = kzalloc(sizeof(struct codec_list), GFP_KERNEL);
 | 
						|
	if (!ptr) {
 | 
						|
		dprintk(1, KERN_ERR "videocodec_register: no memory\n");
 | 
						|
		return -ENOMEM;
 | 
						|
	}
 | 
						|
	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
 | 
						|
static int proc_videocodecs_show(struct seq_file *m, void *v)
 | 
						|
{
 | 
						|
	struct codec_list *h = codeclist_top;
 | 
						|
	struct attached_list *a;
 | 
						|
 | 
						|
	seq_printf(m, "<S>lave or attached <M>aster name  type flags    magic    ");
 | 
						|
	seq_printf(m, "(connected as)\n");
 | 
						|
 | 
						|
	h = codeclist_top;
 | 
						|
	while (h) {
 | 
						|
		seq_printf(m, "S %32s %04x %08lx %08lx (TEMPLATE)\n",
 | 
						|
			      h->codec->name, h->codec->type,
 | 
						|
			      h->codec->flags, h->codec->magic);
 | 
						|
		a = h->list;
 | 
						|
		while (a) {
 | 
						|
			seq_printf(m, "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 0;
 | 
						|
}
 | 
						|
 | 
						|
static int proc_videocodecs_open(struct inode *inode, struct file *file)
 | 
						|
{
 | 
						|
	return single_open(file, proc_videocodecs_show, NULL);
 | 
						|
}
 | 
						|
 | 
						|
static const struct file_operations videocodecs_proc_fops = {
 | 
						|
	.owner		= THIS_MODULE,
 | 
						|
	.open		= proc_videocodecs_open,
 | 
						|
	.read		= seq_read,
 | 
						|
	.llseek		= seq_lseek,
 | 
						|
	.release	= single_release,
 | 
						|
};
 | 
						|
#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_proc_entry = proc_create("videocodecs", 0, NULL, &videocodecs_proc_fops);
 | 
						|
	if (!videocodec_proc_entry) {
 | 
						|
		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);
 | 
						|
#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");
 |