text: /*
   * Video capture interface for Linux
   *
   *		A generic video device interface for the LINUX operating system
   *		using a set of device structures/vectors for low level operations.
   *
   *		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.
   *
   * Author:	Alan Cox, <alan@redhat.com>
   *
   * Fixes:	20000516  Claudio Matsuoka <claudio@conectiva.com>
   *		- Added procfs support
   */
  
  #include <linux/config.h>
  #include <linux/version.h>
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/smp_lock.h>
  #include <linux/mm.h>
  #include <linux/string.h>
  #include <linux/errno.h>
  #include <linux/videodev.h>
  #include <linux/init.h>
  
  #include <asm/uaccess.h>
  #include <asm/system.h>
  
  #include <linux/kmod.h>
  
  
  #define VIDEO_NUM_DEVICES	256 
  
  /*
   *	Active devices 
   */
   
  static struct video_device *video_device[VIDEO_NUM_DEVICES];
  
  
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  
  #include <linux/proc_fs.h>
  
  struct videodev_proc_data {
  	struct list_head proc_list;
  	char name[16];
  	struct video_device *vdev;
  	struct proc_dir_entry *proc_entry;
  };
  
  static struct proc_dir_entry *video_dev_proc_entry = NULL;
  struct proc_dir_entry *video_proc_entry = NULL;
  EXPORT_SYMBOL(video_proc_entry);
  LIST_HEAD(videodev_proc_list);
  
  #endif /* CONFIG_PROC_FS && CONFIG_VIDEO_PROC_FS */
  
  
  #ifdef CONFIG_VIDEO_BWQCAM
  extern int init_bw_qcams(struct video_init *);
  #endif
  #ifdef CONFIG_VIDEO_CPIA
  extern int cpia_init(struct video_init *);
  #endif
  #ifdef CONFIG_VIDEO_PLANB
  extern int init_planbs(struct video_init *);
  #endif
  #ifdef CONFIG_VIDEO_ZORAN
  extern int init_zoran_cards(struct video_init *);
  #endif
  
  static struct video_init video_init_list[]={
  #ifdef CONFIG_VIDEO_BWQCAM
  	{"bw-qcam", init_bw_qcams},
  #endif	
  #ifdef CONFIG_VIDEO_CPIA
  	{"cpia", cpia_init},
  #endif	
  #ifdef CONFIG_VIDEO_PLANB
  	{"planb", init_planbs},
  #endif
  #ifdef CONFIG_VIDEO_ZORAN
  	{"zoran", init_zoran_cards},
  #endif	
  	{"end", NULL}
  };
  
  /*
   *	Read will do some smarts later on. Buffer pin etc.
   */
   
  static ssize_t video_read(struct file *file,
  	char *buf, size_t count, loff_t *ppos)
  {
  	struct video_device *vfl=video_device[MINOR(file->f_dentry->d_inode->i_rdev)];
  	if(vfl->read)
  		return vfl->read(vfl, buf, count, file->f_flags&O_NONBLOCK);
  	else
  		return -EINVAL;
  }
  
  
  /*
   *	Write for now does nothing. No reason it shouldnt do overlay setting
   *	for some boards I guess..
   */
  
  static ssize_t video_write(struct file *file, const char *buf, 
  	size_t count, loff_t *ppos)
  {
  	struct video_device *vfl=video_device[MINOR(file->f_dentry->d_inode->i_rdev)];
  	if(vfl->write)
  		return vfl->write(vfl, buf, count, file->f_flags&O_NONBLOCK);
  	else
  		return 0;
  }
  
  /*
   *	Poll to see if we're readable, can probably be used for timing on incoming
   *  frames, etc..
   */
  
  static unsigned int video_poll(struct file *file, poll_table * wait)
  {
  	struct video_device *vfl=video_device[MINOR(file->f_dentry->d_inode->i_rdev)];
  	if(vfl->poll)
  		return vfl->poll(vfl, file, wait);
  	else
  		return 0;
  }
  
  
  /*
   *	Open a video device.
   */
  
  static int video_open(struct inode *inode, struct file *file)
  {
  	unsigned int minor = MINOR(inode->i_rdev);
  	int err, retval = 0;
  	struct video_device *vfl;
  	
  	if(minor>=VIDEO_NUM_DEVICES)
  		return -ENODEV;
  	lock_kernel();		
  	vfl=video_device[minor];
  	if(vfl==NULL) {
  		char modname[20];
  
  		sprintf (modname, "char-major-%d-%d", VIDEO_MAJOR, minor);
  		request_module(modname);
  		vfl=video_device[minor];
  		if (vfl==NULL) {
  			retval = -ENODEV;
  			goto error_out;
  		}
  	}
  	if(vfl->busy) {
  		retval = -EBUSY;
  		goto error_out;
  	}
  	vfl->busy=1;		/* In case vfl->open sleeps */
  	unlock_kernel();
  	
  	if(vfl->open)
  	{
  		err=vfl->open(vfl,0);	/* Tell the device it is open */
  		if(err)
  		{
  			vfl->busy=0;
  			return err;
  		}
  	}
  	return 0;
  error_out:
  	unlock_kernel();
  	return retval;
  }
  
  /*
   *	Last close of a video for Linux device
   */
  	
  static int video_release(struct inode *inode, struct file *file)
  {
  	struct video_device *vfl;
  	lock_kernel();
  	vfl=video_device[MINOR(inode->i_rdev)];
  	if(vfl->close)
  		vfl->close(vfl);
  	vfl->busy=0;
  	unlock_kernel();
  	return 0;
  }
  
  /*
   *	Question: Should we be able to capture and then seek around the
   *	image ?
   */
   
  static long long video_lseek(struct file * file,
  			  long long offset, int origin)
  {
  	return -ESPIPE;
  }
  
  static int video_ioctl(struct inode *inode, struct file *file,
  	unsigned int cmd, unsigned long arg)
  {
  	struct video_device *vfl=video_device[MINOR(inode->i_rdev)];
  	int err=vfl->ioctl(vfl, cmd, (void *)arg);
  
  	if(err!=-ENOIOCTLCMD)
  		return err;
  	
  	switch(cmd)
  	{
  		default:
  			return -EINVAL;
  	}
  }
  
  /*
   *	We need to do MMAP support
   */
   
   
  int video_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	int ret = -EINVAL;
  	struct video_device *vfl=video_device[MINOR(file->f_dentry->d_inode->i_rdev)];
  	if(vfl->mmap) {
  		lock_kernel();
  		ret = vfl->mmap(vfl, (char *)vma->vm_start, 
  				(unsigned long)(vma->vm_end-vma->vm_start));
  		unlock_kernel();
  	}
  	return ret;
  }
  
  /*
   *	/proc support
   */
  
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  
  /* Hmm... i'd like to see video_capability information here, but
   * how can I access it (without changing the other drivers? -claudio
   */
  static int videodev_proc_read(char *page, char **start, off_t off,
  			       int count, int *eof, void *data)
  {
  	char *out = page;
  	struct video_device *vfd = data;
  	struct videodev_proc_data *d;
  	struct list_head *tmp;
  	int len;
  	char c = ' ';
  
  	list_for_each (tmp, &videodev_proc_list) {
  		d = list_entry(tmp, struct videodev_proc_data, proc_list);
  		if (vfd == d->vdev)
  			break;
  	}
  
  	/* Sanity check */
  	if (tmp == &videodev_proc_list)
  		goto skip;
  		
  #define PRINT_VID_TYPE(x) do { if (vfd->type & x) \
  	out += sprintf (out, "%c%s", c, #x); c='|';} while (0)
  
  	out += sprintf (out, "name            : %s\n", vfd->name);
  	out += sprintf (out, "type            :");
  		PRINT_VID_TYPE(VID_TYPE_CAPTURE);
  		PRINT_VID_TYPE(VID_TYPE_TUNER);
  		PRINT_VID_TYPE(VID_TYPE_TELETEXT);
  		PRINT_VID_TYPE(VID_TYPE_OVERLAY);
  		PRINT_VID_TYPE(VID_TYPE_CHROMAKEY);
  		PRINT_VID_TYPE(VID_TYPE_CLIPPING);
  		PRINT_VID_TYPE(VID_TYPE_FRAMERAM);
  		PRINT_VID_TYPE(VID_TYPE_SCALES);
  		PRINT_VID_TYPE(VID_TYPE_MONOCHROME);
  		PRINT_VID_TYPE(VID_TYPE_SUBCAPTURE);
  		PRINT_VID_TYPE(VID_TYPE_MPEG_DECODER);
  		PRINT_VID_TYPE(VID_TYPE_MPEG_ENCODER);
  		PRINT_VID_TYPE(VID_TYPE_MJPEG_DECODER);
  		PRINT_VID_TYPE(VID_TYPE_MJPEG_ENCODER);
  	out += sprintf (out, "\n");
  	out += sprintf (out, "hardware        : 0x%x\n", vfd->hardware);
  #if 0
  	out += sprintf (out, "channels        : %d\n", d->vcap.channels);
  	out += sprintf (out, "audios          : %d\n", d->vcap.audios);
  	out += sprintf (out, "maxwidth        : %d\n", d->vcap.maxwidth);
  	out += sprintf (out, "maxheight       : %d\n", d->vcap.maxheight);
  	out += sprintf (out, "minwidth        : %d\n", d->vcap.minwidth);
  	out += sprintf (out, "minheight       : %d\n", d->vcap.minheight);
  #endif
  
  skip:
  	len = out - page;
  	len -= off;
  	if (len < count) {
  		*eof = 1;
  		if (len <= 0)
  			return 0;
  	} else
  		len = count;
  
  	*start = page + off;
  
  	return len;
  }
  
  static void videodev_proc_create(void)
  {
  	video_proc_entry = create_proc_entry("video", S_IFDIR, &proc_root);
  
  	if (video_proc_entry == NULL) {
  		printk("video_dev: unable to initialise /proc/video\n");
  		return;
  	}
  
  	video_proc_entry->owner = THIS_MODULE;
  	video_dev_proc_entry = create_proc_entry("dev", S_IFDIR, video_proc_entry);
  
  	if (video_dev_proc_entry == NULL) {
  		printk("video_dev: unable to initialise /proc/video/dev\n");
  		return;
  	}
  
  	video_dev_proc_entry->owner = THIS_MODULE;
  }
  
  #ifdef MODULE
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  static void videodev_proc_destroy(void)
  {
  	if (video_dev_proc_entry != NULL)
  		remove_proc_entry("dev", video_proc_entry);
  
  	if (video_proc_entry != NULL)
  		remove_proc_entry("video", &proc_root);
  }
  #endif
  #endif
  
  static void videodev_proc_create_dev (struct video_device *vfd, char *name)
  {
  	struct videodev_proc_data *d;
  	struct proc_dir_entry *p;
  
  	if (video_dev_proc_entry == NULL)
  		return;
  
  	d = kmalloc (sizeof (struct videodev_proc_data), GFP_KERNEL);
  	if (!d)
  		return;
  
  	p = create_proc_entry(name, S_IFREG|S_IRUGO|S_IWUSR, video_dev_proc_entry);
  	p->data = vfd;
  	p->read_proc = videodev_proc_read;
  
  	d->proc_entry = p;
  	d->vdev = vfd;
  	strcpy (d->name, name);
  
  	/* How can I get capability information ? */
  
  	list_add (&d->proc_list, &videodev_proc_list);
  }
  
  static void videodev_proc_destroy_dev (struct video_device *vfd)
  {
  	struct list_head *tmp;
  	struct videodev_proc_data *d;
  
  	list_for_each (tmp, &videodev_proc_list) {
  		d = list_entry(tmp, struct videodev_proc_data, proc_list);
  		if (vfd == d->vdev) {
  			remove_proc_entry(d->name, video_dev_proc_entry);
  			list_del (&d->proc_list);
  			kfree (d);
  			break;
  		}
  	}
  }
  
  #endif /* CONFIG_VIDEO_PROC_FS */
  
  extern struct file_operations video_fops;
  
  /**
   *	video_register_device - register video4linux devices
   *	@vfd: video device structure we want to register
   *	@type: type of device to register
   *	FIXME: needs a semaphore on 2.3.x
   *	
   *	The registration code assigns minor numbers based on the type
   *	requested. -ENFILE is returned in all the device slots for this
   *	category are full. If not then the minor field is set and the
   *	driver initialize function is called (if non %NULL).
   *
   *	Zero is returned on success.
   *
   *	Valid types are
   *
   *	%VFL_TYPE_GRABBER - A frame grabber
   *
   *	%VFL_TYPE_VTX - A teletext device
   *
   *	%VFL_TYPE_VBI - Vertical blank data (undecoded)
   *
   *	%VFL_TYPE_RADIO - A radio card	
   */
   
  int video_register_device(struct video_device *vfd, int type)
  {
  	int i=0;
  	int base;
  	int err;
  	int end;
  	char *name_base;
  	
  	switch(type)
  	{
  		case VFL_TYPE_GRABBER:
  			base=0;
  			end=64;
  			name_base = "video";
  			break;
  		case VFL_TYPE_VTX:
  			base=192;
  			end=224;
  			name_base = "vtx";
  			break;
  		case VFL_TYPE_VBI:
  			base=224;
  			end=240;
  			name_base = "vbi";
  			break;
  		case VFL_TYPE_RADIO:
  			base=64;
  			end=128;
  			name_base = "radio";
  			break;
  		default:
  			return -1;
  	}
  	
  	for(i=base;i<end;i++)
  	{
  		if(video_device[i]==NULL)
  		{
  			char name[16];
  
  			video_device[i]=vfd;
  			vfd->minor=i;
  			/* The init call may sleep so we book the slot out
  			   then call */
  			MOD_INC_USE_COUNT;
  			if(vfd->initialize)
  			{
  				err=vfd->initialize(vfd);
  				if(err<0)
  				{
  					video_device[i]=NULL;
  					MOD_DEC_USE_COUNT;
  					return err;
  				}
  			}
  			sprintf (name, "v4l/%s%d", name_base, i - base);
  			/*
  			 *	Start the device root only. Anything else
  			 *	has serious privacy issues.
  			 */
  			vfd->devfs_handle =
  			    devfs_register (NULL, name, DEVFS_FL_DEFAULT,
  					    VIDEO_MAJOR, vfd->minor,
  					    S_IFCHR | S_IRUSR | S_IWUSR,
  					    &video_fops, NULL);
  
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  			sprintf (name, "%s%d", name_base, i - base);
  			videodev_proc_create_dev (vfd, name);
  #endif
  			
  
  			return 0;
  		}
  	}
  	return -ENFILE;
  }
  
  /**
   *	video_unregister_device - unregister a video4linux device
   *	@vfd: the device to unregister
   *
   *	This unregisters the passed device and deassigns the minor
   *	number. Future open calls will be met with errors.
   */
   
  void video_unregister_device(struct video_device *vfd)
  {
  	if(video_device[vfd->minor]!=vfd)
  		panic("vfd: bad unregister");
  
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  	videodev_proc_destroy_dev (vfd);
  #endif
  
  	devfs_unregister (vfd->devfs_handle);
  	video_device[vfd->minor]=NULL;
  	MOD_DEC_USE_COUNT;
  }
  
  
  static struct file_operations video_fops=
  {
  	owner:		THIS_MODULE,
  	llseek:		video_lseek,
  	read:		video_read,
  	write:		video_write,
  	ioctl:		video_ioctl,
  	mmap:		video_mmap,
  	open:		video_open,
  	release:	video_release,
  	poll:		video_poll,
  };
  
  /*
   *	Initialise video for linux
   */
   
  int __init videodev_init(void)
  {
  	struct video_init *vfli = video_init_list;
  	
  	printk(KERN_INFO "Linux video capture interface: v1.00\n");
  	if(devfs_register_chrdev(VIDEO_MAJOR,"video_capture", &video_fops))
  	{
  		printk("video_dev: unable to get major %d\n", VIDEO_MAJOR);
  		return -EIO;
  	}
  
  	/*
  	 *	Init kernel installed video drivers
  	 */
  	 	
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  	videodev_proc_create ();
  #endif
  	
  	while(vfli->init!=NULL)
  	{
  		vfli->init(vfli);
  		vfli++;
  	}
  	return 0;
  }
  
  #ifdef MODULE		
  int init_module(void)
  {
  	return videodev_init();
  }
  
  void cleanup_module(void)
  {
  #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
  	videodev_proc_destroy ();
  #endif
  	
  	devfs_unregister_chrdev(VIDEO_MAJOR, "video_capture");
  }
  
  #endif
  
  EXPORT_SYMBOL(video_register_device);
  EXPORT_SYMBOL(video_unregister_device);
  
  MODULE_AUTHOR("Alan Cox");
  MODULE_DESCRIPTION("Device registrar for Video4Linux drivers");
  