v4l1-compat.c

这是一个市场上常见电视卡的驱动程序源代码

/*
 *	Video for Linux Two
 *	Backward Compatibility Layer
 *
 *	Support subroutines for providing V4L2 drivers with backward
 *	compatibility with applications using the old API.
 *
 *	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:	Bill Dirks <[e-mail]>
 *		et al.
 *
 */

#ifndef __KERNEL__
#define __KERNEL__
#endif

#include <linux/config.h>

#include <linux/version.h>
#include <linux/init.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/fs.h>
#include <linux/file.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/videodev.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/pgtable.h>

#ifdef CONFIG_KMOD
#include <linux/kmod.h>
#endif

static unsigned int debug  = 0;
MODULE_PARM(debug,"i");
MODULE_PARM_DESC(debug,"enable debug messages");
MODULE_AUTHOR("Bill Dirks");
MODULE_DESCRIPTION("v4l(1) compatibility layer for v4l2 drivers.");
MODULE_LICENSE("GPL");

#define dprintk(fmt, arg...)	if (debug) \
	printk(KERN_DEBUG "v4l1-compat: " fmt , ## arg)

/*
 *	I O C T L   T R A N S L A T I O N
 *
 *	From here on down is the code for translating the numerous
 *	ioctl commands from the old API to the new API.
 */

static int
get_v4l_control(struct inode            *inode,
		struct file             *file,
		int			cid,
		v4l2_kioctl             drv)
{
	struct v4l2_queryctrl	qctrl2;
	struct v4l2_control	ctrl2;
	int			err;

	qctrl2.id = cid;
	err = drv(inode, file, VIDIOC_QUERYCTRL, &qctrl2);
	if (err < 0)
		dprintk("VIDIOC_QUERYCTRL: %d\n",err);
	if (err == 0 &&
	    !(qctrl2.flags & V4L2_CTRL_FLAG_DISABLED))
	{
		ctrl2.id = qctrl2.id;
		err = drv(inode, file, VIDIOC_G_CTRL, &ctrl2);
		if (err < 0) {
			dprintk("VIDIOC_G_CTRL: %d\n",err);
			return 0;
		}
		return ((ctrl2.value - qctrl2.minimum) * 65535
			 + (qctrl2.maximum - qctrl2.minimum) / 2)
			/ (qctrl2.maximum - qctrl2.minimum);
	}
	return 0;
}

static int
set_v4l_control(struct inode            *inode,
		struct file             *file,
		int			cid,
		int			value,
		v4l2_kioctl             drv)
{
	struct v4l2_queryctrl	qctrl2;
	struct v4l2_control	ctrl2;
	int			err;

	qctrl2.id = cid;
	err = drv(inode, file, VIDIOC_QUERYCTRL, &qctrl2);
	if (err < 0)
		dprintk("VIDIOC_QUERYCTRL: %d\n",err);
	if (err == 0 &&
	    !(qctrl2.flags & V4L2_CTRL_FLAG_DISABLED) &&
	    !(qctrl2.flags & V4L2_CTRL_FLAG_GRABBED))
	{
		if (value < 0)
			value = 0;
		if (value > 65535)
			value = 65535;
		if (value && qctrl2.type == V4L2_CTRL_TYPE_BOOLEAN)
			value = 65535;
		ctrl2.id = qctrl2.id;
		ctrl2.value = 
			(value * (qctrl2.maximum - qctrl2.minimum)
			 + 32767)
			/ 65535;
		ctrl2.value += qctrl2.minimum;
		err = drv(inode, file, VIDIOC_S_CTRL, &ctrl2);
		if (err < 0)
			dprintk("VIDIOC_S_CTRL: %d\n",err);
	}
	return 0;
}

/* ----------------------------------------------------------------- */

static int palette2pixelformat[] = {
	[VIDEO_PALETTE_GREY]    = V4L2_PIX_FMT_GREY,
	[VIDEO_PALETTE_RGB555]  = V4L2_PIX_FMT_RGB555,
	[VIDEO_PALETTE_RGB565]  = V4L2_PIX_FMT_RGB565,
	[VIDEO_PALETTE_RGB24]   = V4L2_PIX_FMT_BGR24,
	[VIDEO_PALETTE_RGB32]   = V4L2_PIX_FMT_BGR32,
	/* yuv packed pixel */
	[VIDEO_PALETTE_YUYV]    = V4L2_PIX_FMT_YUYV,
	[VIDEO_PALETTE_YUV422]  = V4L2_PIX_FMT_YUYV,
	[VIDEO_PALETTE_UYVY]    = V4L2_PIX_FMT_UYVY,
	/* yuv planar */
	[VIDEO_PALETTE_YUV410P] = V4L2_PIX_FMT_YUV410,
	[VIDEO_PALETTE_YUV420]  = V4L2_PIX_FMT_YUV420,
	[VIDEO_PALETTE_YUV420P] = V4L2_PIX_FMT_YUV420,
	[VIDEO_PALETTE_YUV411P] = V4L2_PIX_FMT_YUV411P,
	[VIDEO_PALETTE_YUV422P] = V4L2_PIX_FMT_YUV422P,
};

static unsigned int
palette_to_pixelformat(unsigned int palette)
{
	if (palette < ARRAY_SIZE(palette2pixelformat))
		return palette2pixelformat[palette];
	else
		return 0;
}

static unsigned int
pixelformat_to_palette(int pixelformat)
{
	int	palette = 0;
	switch (pixelformat)
	{
	case V4L2_PIX_FMT_GREY:
		palette = VIDEO_PALETTE_GREY;
		break;
	case V4L2_PIX_FMT_RGB555:
		palette = VIDEO_PALETTE_RGB555;
		break;
	case V4L2_PIX_FMT_RGB565:
		palette = VIDEO_PALETTE_RGB565;
		break;
	case V4L2_PIX_FMT_BGR24:
		palette = VIDEO_PALETTE_RGB24;
		break;
	case V4L2_PIX_FMT_BGR32:
		palette = VIDEO_PALETTE_RGB32;
		break;
	/* yuv packed pixel */
	case V4L2_PIX_FMT_YUYV:
		palette = VIDEO_PALETTE_YUYV;
		break;
	case V4L2_PIX_FMT_UYVY:
		palette = VIDEO_PALETTE_UYVY;
		break;
	/* yuv planar */
	case V4L2_PIX_FMT_YUV410:
		palette = VIDEO_PALETTE_YUV420;
		break;
	case V4L2_PIX_FMT_YUV420:
		palette = VIDEO_PALETTE_YUV420;
		break;
	case V4L2_PIX_FMT_YUV411P:
		palette = VIDEO_PALETTE_YUV411P;
		break;
	case V4L2_PIX_FMT_YUV422P:
		palette = VIDEO_PALETTE_YUV422P;
		break;
	}
	return palette;
}

/* ----------------------------------------------------------------- */

static int poll_one(struct file *file)
{
	int retval = 1;
	poll_table *table;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,48)
	poll_table wait_table;

	poll_initwait(&wait_table);
	table = &wait_table;
#else
	struct poll_wqueues pwq;

	poll_initwait(&pwq);
	table = &pwq.pt;
#endif
	for (;;) {
		int mask;
		set_current_state(TASK_INTERRUPTIBLE);
		mask = file->f_op->poll(file, table);
		if (mask & POLLIN)
			break;
		table = NULL;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	set_current_state(TASK_RUNNING);
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,48)
	poll_freewait(&wait_table);
#else
	poll_freewait(&pwq);
#endif
	return retval;
}

static int count_inputs(struct inode         *inode,
			struct file          *file,
			v4l2_kioctl          drv)
{
	struct v4l2_input input2;
	int i;

	for (i = 0;; i++) {
		memset(&input2,0,sizeof(input2));
		input2.index = i;
		if (0 != drv(inode,file,VIDIOC_ENUMINPUT, &input2))
			break;
	}
	return i;
}

static int check_size(struct inode         *inode,
		      struct file          *file,
		      v4l2_kioctl          drv,
		      int *maxw, int *maxh)
{
	struct v4l2_fmtdesc desc2;
	struct v4l2_format  fmt2;

	memset(&desc2,0,sizeof(desc2));
	memset(&fmt2,0,sizeof(fmt2));
	
	desc2.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
	if (0 != drv(inode,file,VIDIOC_ENUM_FMT, &desc2))
		goto done;

	fmt2.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
	fmt2.fmt.pix.width       = 10000;
	fmt2.fmt.pix.height      = 10000;
	fmt2.fmt.pix.pixelformat = desc2.pixelformat;
	if (0 != drv(inode,file,VIDIOC_TRY_FMT, &fmt2))
		goto done;

	*maxw = fmt2.fmt.pix.width;
	*maxh = fmt2.fmt.pix.height;

 done:
	return 0;
}

/* ----------------------------------------------------------------- */

/*
 *	This function is exported.
 */
int
v4l_compat_translate_ioctl(struct inode         *inode,
			   struct file		*file,
			   int			cmd,
			   void			*arg,
			   v4l2_kioctl          drv)
{
	struct v4l2_capability  *cap2 = NULL;
	struct v4l2_format	*fmt2 = NULL;

	struct v4l2_framebuffer fbuf2;
	struct v4l2_input	input2;
	struct v4l2_tuner	tun2;
	struct v4l2_standard	std2;
	struct v4l2_frequency   freq2;
	struct v4l2_audio	aud2;
	struct v4l2_queryctrl	qctrl2;
	struct v4l2_buffer	buf2;
	v4l2_std_id    		sid;
	int i, err = 0;

	switch (cmd) {
	case VIDIOCGCAP:	/* capability */
	{
		struct video_capability *cap = arg;

		cap2 = kmalloc(sizeof(*cap2),GFP_KERNEL);
		memset(cap, 0, sizeof(*cap));
		memset(cap2, 0, sizeof(*cap2));
		memset(&fbuf2, 0, sizeof(fbuf2));

		err = drv(inode, file, VIDIOC_QUERYCAP, cap2);
		if (err < 0) {
			dprintk("VIDIOCGCAP / VIDIOC_QUERYCAP: %d\n",err);
			break;
		}
		if (cap2->capabilities & V4L2_CAP_VIDEO_OVERLAY) {
			err = drv(inode, file, VIDIOC_G_FBUF, &fbuf2);
			if (err < 0) {
				dprintk("VIDIOCGCAP / VIDIOC_G_FBUF: %d\n",err);
				memset(&fbuf2, 0, sizeof(fbuf2));
			}
			err = 0;
		}

		memcpy(cap->name, cap2->card, 
		       min(sizeof(cap->name), sizeof(cap2->card)));
		cap->name[sizeof(cap->name) - 1] = 0;
		if (cap2->capabilities & V4L2_CAP_VIDEO_CAPTURE)
			cap->type |= VID_TYPE_CAPTURE;
		if (cap2->capabilities & V4L2_CAP_TUNER)
			cap->type |= VID_TYPE_TUNER;
		if (cap2->capabilities & V4L2_CAP_VBI_CAPTURE)
			cap->type |= VID_TYPE_TELETEXT;
		if (cap2->capabilities & V4L2_CAP_VIDEO_OVERLAY)
			cap->type |= VID_TYPE_OVERLAY;
		if (fbuf2.capability & V4L2_FBUF_CAP_LIST_CLIPPING)
			cap->type |= VID_TYPE_CLIPPING;

		cap->channels  = count_inputs(inode,file,drv);
		check_size(inode,file,drv,
			   &cap->maxwidth,&cap->maxheight);
		cap->audios    =  0; /* FIXME */
		cap->minwidth  = 48; /* FIXME */
		cap->minheight = 32; /* FIXME */
		break;
	}
	case VIDIOCGFBUF: /*  get frame buffer  */
	{
		struct video_buffer	*buffer = arg;

		err = drv(inode, file, VIDIOC_G_FBUF, &fbuf2);
		if (err < 0) {
			dprintk("VIDIOCGFBUF / VIDIOC_G_FBUF: %d\n",err);
			break;
		}
		buffer->base   = fbuf2.base;
		buffer->height = fbuf2.fmt.height;
		buffer->width  = fbuf2.fmt.width;

		switch (fbuf2.fmt.pixelformat) {
		case V4L2_PIX_FMT_RGB332:
			buffer->depth = 8;
				break;
		case V4L2_PIX_FMT_RGB555:
			buffer->depth = 15;
			break;
		case V4L2_PIX_FMT_RGB565:
			buffer->depth = 16;
			break;
		case V4L2_PIX_FMT_BGR24:
			buffer->depth = 24;
			break;
		case V4L2_PIX_FMT_BGR32:
			buffer->depth = 32;
			break;
		default:
			buffer->depth = 0;
		}
		if (0 != fbuf2.fmt.bytesperline)
			buffer->bytesperline = fbuf2.fmt.bytesperline;
		else {
			buffer->bytesperline = 
				(buffer->width * buffer->depth + 7) & 7;
			buffer->bytesperline >>= 3;
		}
		break;
	}
	case VIDIOCSFBUF: /*  set frame buffer  */
	{
		struct video_buffer	*buffer = arg;

		memset(&fbuf2, 0, sizeof(fbuf2));
		fbuf2.base       = buffer->base;
		fbuf2.fmt.height = buffer->height;
		fbuf2.fmt.width  = buffer->width;
		switch (buffer->depth) {
		case 8:
			fbuf2.fmt.pixelformat = V4L2_PIX_FMT_RGB332;
			break;
		case 15:
			fbuf2.fmt.pixelformat = V4L2_PIX_FMT_RGB555;
			break;
		case 16:
			fbuf2.fmt.pixelformat = V4L2_PIX_FMT_RGB565;
			break;
		case 24:
			fbuf2.fmt.pixelformat = V4L2_PIX_FMT_BGR24;
			break;
		case 32:
			fbuf2.fmt.pixelformat = V4L2_PIX_FMT_BGR32;
			break;
		}
		fbuf2.fmt.bytesperline = buffer->bytesperline;
		err = drv(inode, file, VIDIOC_S_FBUF, &fbuf2);
		if (err < 0)
			dprintk("VIDIOCSFBUF / VIDIOC_S_FBUF: %d\n",err);
		break;
	}
	case VIDIOCGWIN: /*  get window or capture dimensions  */
	{
		struct video_window	*win = arg;

		fmt2 = kmalloc(sizeof(*fmt2),GFP_KERNEL);
		memset(win,0,sizeof(*win));
		memset(fmt2,0,sizeof(*fmt2));

		fmt2->type = V4L2_BUF_TYPE_VIDEO_OVERLAY;
		err = drv(inode, file, VIDIOC_G_FMT, fmt2);
		if (err < 0)
			dprintk("VIDIOCGWIN / VIDIOC_G_WIN: %d\n",err);
		if (err == 0) {
			win->x         = fmt2->fmt.win.w.left;
			win->y         = fmt2->fmt.win.w.top;
			win->width     = fmt2->fmt.win.w.width;
			win->height    = fmt2->fmt.win.w.height;
			win->chromakey = fmt2->fmt.win.chromakey;
			win->clips     = NULL;
			win->clipcount = 0;
			break;
		}

		fmt2->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		err = drv(inode, file, VIDIOC_G_FMT, fmt2);
		if (err < 0) {
			dprintk("VIDIOCGWIN / VIDIOC_G_FMT: %d\n",err);
			break;
		}
		win->x         = 0;
		win->y         = 0;
		win->width     = fmt2->fmt.pix.width;
		win->height    = fmt2->fmt.pix.height;
		win->chromakey = 0;
		win->clips     = NULL;
		win->clipcount = 0;
		break;
	}
	case VIDIOCSWIN: /*  set window and/or capture dimensions  */
	{
		struct video_window	*win = arg;
		int err1,err2;

		fmt2 = kmalloc(sizeof(*fmt2),GFP_KERNEL);
		memset(fmt2,0,sizeof(*fmt2));
		fmt2->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		err1 = drv(inode, file, VIDIOC_G_FMT, fmt2);
		if (err1 < 0)
			dprintk("VIDIOCSWIN / VIDIOC_G_FMT: %d\n",err);
		if (err1 == 0) {
			fmt2->fmt.pix.width  = win->width;
			fmt2->fmt.pix.height = win->height;
			fmt2->fmt.pix.field  = V4L2_FIELD_ANY;
			fmt2->fmt.pix.bytesperline = 0;
			err = drv(inode, file, VIDIOC_S_FMT, fmt2);
			if (err < 0)
				dprintk("VIDIOCSWIN / VIDIOC_S_FMT #1: %d\n",
					err);
			win->width  = fmt2->fmt.pix.width;
			win->height = fmt2->fmt.pix.height;
		}

		memset(fmt2,0,sizeof(*fmt2));
		fmt2->type = V4L2_BUF_TYPE_VIDEO_OVERLAY;
		fmt2->fmt.win.w.left    = win->x;
		fmt2->fmt.win.w.top     = win->y;
		fmt2->fmt.win.w.width   = win->width;
		fmt2->fmt.win.w.height  = win->height;
		fmt2->fmt.win.chromakey = win->chromakey;
		fmt2->fmt.win.clips     = (void *)win->clips;
		fmt2->fmt.win.clipcount = win->clipcount;
		err2 = drv(inode, file, VIDIOC_S_FMT, fmt2);
		if (err2 < 0)
			dprintk("VIDIOCSWIN / VIDIOC_S_FMT #2: %d\n",err);

		if (err1 != 0 && err2 != 0)
			err = err1;
		break;
	}
	case VIDIOCCAPTURE: /*  turn on/off preview  */
	{
		int *on = arg;

		if (0 == *on) {
			/* dirty hack time.  But v4l1 has no STREAMOFF
			 * equivalent in the API, and this one at
			 * least comes close ... */