drivers/media/video/cx25840/cx25840-vbi.c - maze/linux - Git at Google

 /* cx25840 VBI functions
  *
  * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  */


 #include <linux/videodev2.h>
 #include <linux/i2c.h>
 #include <media/v4l2-common.h>

 #include "cx25840.h"

 static inline int odd_parity(u8 c)
 {
 	c ^= (c >> 4);
 	c ^= (c >> 2);
 	c ^= (c >> 1);

 	return c & 1;
 }

 static inline int decode_vps(u8 * dst, u8 * p)
 {
 	static const u8 biphase_tbl[] = {
 		0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
 		0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
 		0xd2, 0x5a, 0x52, 0xd2, 0x96, 0x1e, 0x16, 0x96,
 		0x92, 0x1a, 0x12, 0x92, 0xd2, 0x5a, 0x52, 0xd2,
 		0xd0, 0x58, 0x50, 0xd0, 0x94, 0x1c, 0x14, 0x94,
 		0x90, 0x18, 0x10, 0x90, 0xd0, 0x58, 0x50, 0xd0,
 		0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
 		0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
 		0xe1, 0x69, 0x61, 0xe1, 0xa5, 0x2d, 0x25, 0xa5,
 		0xa1, 0x29, 0x21, 0xa1, 0xe1, 0x69, 0x61, 0xe1,
 		0xc3, 0x4b, 0x43, 0xc3, 0x87, 0x0f, 0x07, 0x87,
 		0x83, 0x0b, 0x03, 0x83, 0xc3, 0x4b, 0x43, 0xc3,
 		0xc1, 0x49, 0x41, 0xc1, 0x85, 0x0d, 0x05, 0x85,
 		0x81, 0x09, 0x01, 0x81, 0xc1, 0x49, 0x41, 0xc1,
 		0xe1, 0x69, 0x61, 0xe1, 0xa5, 0x2d, 0x25, 0xa5,
 		0xa1, 0x29, 0x21, 0xa1, 0xe1, 0x69, 0x61, 0xe1,
 		0xe0, 0x68, 0x60, 0xe0, 0xa4, 0x2c, 0x24, 0xa4,
 		0xa0, 0x28, 0x20, 0xa0, 0xe0, 0x68, 0x60, 0xe0,
 		0xc2, 0x4a, 0x42, 0xc2, 0x86, 0x0e, 0x06, 0x86,
 		0x82, 0x0a, 0x02, 0x82, 0xc2, 0x4a, 0x42, 0xc2,
 		0xc0, 0x48, 0x40, 0xc0, 0x84, 0x0c, 0x04, 0x84,
 		0x80, 0x08, 0x00, 0x80, 0xc0, 0x48, 0x40, 0xc0,
 		0xe0, 0x68, 0x60, 0xe0, 0xa4, 0x2c, 0x24, 0xa4,
 		0xa0, 0x28, 0x20, 0xa0, 0xe0, 0x68, 0x60, 0xe0,
 		0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
 		0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
 		0xd2, 0x5a, 0x52, 0xd2, 0x96, 0x1e, 0x16, 0x96,
 		0x92, 0x1a, 0x12, 0x92, 0xd2, 0x5a, 0x52, 0xd2,
 		0xd0, 0x58, 0x50, 0xd0, 0x94, 0x1c, 0x14, 0x94,
 		0x90, 0x18, 0x10, 0x90, 0xd0, 0x58, 0x50, 0xd0,
 		0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
 		0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
 	};

 	u8 c, err = 0;
 	int i;

 	for (i = 0; i < 2 * 13; i += 2) {
 		err |= biphase_tbl[p[i]] | biphase_tbl[p[i + 1]];
 		c = (biphase_tbl[p[i + 1]] & 0xf) |
 		    ((biphase_tbl[p[i]] & 0xf) << 4);
 		dst[i / 2] = c;
 	}

 	return err & 0xf0;
 }

 void cx25840_vbi_setup(struct i2c_client *client)
 {
 	v4l2_std_id std = cx25840_get_v4lstd(client);

 	if (std & ~V4L2_STD_NTSC) {
 		/* datasheet startup, step 8d */
 		cx25840_write(client, 0x49f, 0x11);

 		cx25840_write(client, 0x470, 0x84);
 		cx25840_write(client, 0x471, 0x00);
 		cx25840_write(client, 0x472, 0x2d);
 		cx25840_write(client, 0x473, 0x5d);

 		cx25840_write(client, 0x474, 0x24);
 		cx25840_write(client, 0x475, 0x40);
 		cx25840_write(client, 0x476, 0x24);
 		cx25840_write(client, 0x477, 0x28);

 		cx25840_write(client, 0x478, 0x1f);
 		cx25840_write(client, 0x479, 0x02);

 		if (std & V4L2_STD_SECAM) {
 			cx25840_write(client, 0x47a, 0x80);
 			cx25840_write(client, 0x47b, 0x00);
 			cx25840_write(client, 0x47c, 0x5f);
 			cx25840_write(client, 0x47d, 0x42);
 		} else {
 			cx25840_write(client, 0x47a, 0x90);
 			cx25840_write(client, 0x47b, 0x20);
 			cx25840_write(client, 0x47c, 0x63);
 			cx25840_write(client, 0x47d, 0x82);
 		}

 		cx25840_write(client, 0x47e, 0x0a);
 		cx25840_write(client, 0x47f, 0x01);
 	} else {
 		/* datasheet startup, step 8d */
 		cx25840_write(client, 0x49f, 0x14);

 		cx25840_write(client, 0x470, 0x7a);
 		cx25840_write(client, 0x471, 0x00);
 		cx25840_write(client, 0x472, 0x2d);
 		cx25840_write(client, 0x473, 0x5b);

 		cx25840_write(client, 0x474, 0x1a);
 		cx25840_write(client, 0x475, 0x70);
 		cx25840_write(client, 0x476, 0x1e);
 		cx25840_write(client, 0x477, 0x1e);

 		cx25840_write(client, 0x478, 0x1f);
 		cx25840_write(client, 0x479, 0x02);
 		cx25840_write(client, 0x47a, 0x50);
 		cx25840_write(client, 0x47b, 0x66);

 		cx25840_write(client, 0x47c, 0x1f);
 		cx25840_write(client, 0x47d, 0x7c);
 		cx25840_write(client, 0x47e, 0x08);
 		cx25840_write(client, 0x47f, 0x00);
 	}
 }

 int cx25840_vbi(struct i2c_client *client, unsigned int cmd, void *arg)
 {
 	struct v4l2_format *fmt;
 	struct v4l2_sliced_vbi_format *svbi;

 	switch (cmd) {
 	case VIDIOC_G_FMT:
 	{
 		static u16 lcr2vbi[] = {
 			0, V4L2_SLICED_TELETEXT_B, 0,	/* 1 */
 			0, V4L2_SLICED_WSS_625, 0,	/* 4 */
 			V4L2_SLICED_CAPTION_525,	/* 6 */
 			0, 0, V4L2_SLICED_VPS, 0, 0,	/* 9 */
 			0, 0, 0, 0
 		};
 		int i;

 		fmt = arg;
 		if (fmt->type != V4L2_BUF_TYPE_SLICED_VBI_CAPTURE)
 			return -EINVAL;
 		svbi = &fmt->fmt.sliced;
 		memset(svbi, 0, sizeof(*svbi));
 		/* we're done if raw VBI is active */
 		if ((cx25840_read(client, 0x404) & 0x10) == 0)
 			break;

 		for (i = 7; i <= 23; i++) {
 			u8 v = cx25840_read(client, 0x424 + i - 7);

 			svbi->service_lines[0][i] = lcr2vbi[v >> 4];
 			svbi->service_lines[1][i] = lcr2vbi[v & 0xf];
 			svbi->service_set |=
 				 svbi->service_lines[0][i] | svbi->service_lines[1][i];
 		}
 		break;
 	}

 	case VIDIOC_S_FMT:
 	{
 		int is_pal = !(cx25840_get_v4lstd(client) & V4L2_STD_NTSC);
 		int vbi_offset = is_pal ? 1 : 0;
 		int i, x;
 		u8 lcr[24];

 		fmt = arg;
 		if (fmt->type != V4L2_BUF_TYPE_SLICED_VBI_CAPTURE)
 			return -EINVAL;
 		svbi = &fmt->fmt.sliced;
 		if (svbi->service_set == 0) {
 			/* raw VBI */
 			memset(svbi, 0, sizeof(*svbi));

 			/* Setup VBI */
 			cx25840_vbi_setup(client);

 			/* VBI Offset */
 			cx25840_write(client, 0x47f, vbi_offset);
 			cx25840_write(client, 0x404, 0x2e);
 			break;
 		}

 		for (x = 0; x <= 23; x++)
 			lcr[x] = 0x00;

 		/* Setup VBI */
 		cx25840_vbi_setup(client);

 		/* Sliced VBI */
 		cx25840_write(client, 0x404, 0x36);	/* Ancillery data */
 		cx25840_write(client, 0x406, 0x13);
 		cx25840_write(client, 0x47f, vbi_offset);

 		if (is_pal) {
 			for (i = 0; i <= 6; i++)
 				svbi->service_lines[0][i] =
 					svbi->service_lines[1][i] = 0;
 		} else {
 			for (i = 0; i <= 9; i++)
 				svbi->service_lines[0][i] =
 					svbi->service_lines[1][i] = 0;

 			for (i = 22; i <= 23; i++)
 				svbi->service_lines[0][i] =
 					svbi->service_lines[1][i] = 0;
 		}

 		for (i = 7; i <= 23; i++) {
 			for (x = 0; x <= 1; x++) {
 				switch (svbi->service_lines[1-x][i]) {
 				case V4L2_SLICED_TELETEXT_B:
 					lcr[i] |= 1 << (4 * x);
 					break;
 				case V4L2_SLICED_WSS_625:
 					lcr[i] |= 4 << (4 * x);
 					break;
 				case V4L2_SLICED_CAPTION_525:
 					lcr[i] |= 6 << (4 * x);
 					break;
 				case V4L2_SLICED_VPS:
 					lcr[i] |= 9 << (4 * x);
 					break;
 				}
 			}
 		}

 		for (x = 1, i = 0x424; i <= 0x434; i++, x++) {
 			cx25840_write(client, i, lcr[6 + x]);
 		}

 		cx25840_write(client, 0x43c, 0x16);

 		if (is_pal) {
 			cx25840_write(client, 0x474, 0x2a);
 		} else {
 			cx25840_write(client, 0x474, 0x1a + 6);
 		}
 		break;
 	}

 	case VIDIOC_INT_DECODE_VBI_LINE:
 	{
 		struct v4l2_decode_vbi_line *vbi = arg;
 		u8 *p = vbi->p;
 		int id1, id2, l, err = 0;

 		if (p[0] || p[1] != 0xff || p[2] != 0xff ||
 		    (p[3] != 0x55 && p[3] != 0x91)) {
 			vbi->line = vbi->type = 0;
 			break;
 		}

 		p += 4;
 		id1 = p[-1];
 		id2 = p[0] & 0xf;
 		l = p[2] & 0x3f;
 		l += 5;
 		p += 4;

 		switch (id2) {
 		case 1:
 			id2 = V4L2_SLICED_TELETEXT_B;
 			break;
 		case 4:
 			id2 = V4L2_SLICED_WSS_625;
 			break;
 		case 6:
 			id2 = V4L2_SLICED_CAPTION_525;
 			err = !odd_parity(p[0]) || !odd_parity(p[1]);
 			break;
 		case 9:
 			id2 = V4L2_SLICED_VPS;
 			if (decode_vps(p, p) != 0) {
 				err = 1;
 			}
 			break;
 		default:
 			id2 = 0;
 			err = 1;
 			break;
 		}

 		vbi->type = err ? 0 : id2;
 		vbi->line = err ? 0 : l;
 		vbi->is_second_field = err ? 0 : (id1 == 0x55);
 		vbi->p = p;
 		break;
 	}
 	}

 	return 0;
 }
	/* cx25840 VBI functions
	*
	* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	*/


	#include <linux/videodev2.h>
	#include <linux/i2c.h>
	#include <media/v4l2-common.h>

	#include "cx25840.h"

	static inline int odd_parity(u8 c)
	{
	c ^= (c >> 4);
	c ^= (c >> 2);
	c ^= (c >> 1);

	return c & 1;
	}

	static inline int decode_vps(u8 * dst, u8 * p)
	{
	static const u8 biphase_tbl[] = {
	0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
	0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
	0xd2, 0x5a, 0x52, 0xd2, 0x96, 0x1e, 0x16, 0x96,
	0x92, 0x1a, 0x12, 0x92, 0xd2, 0x5a, 0x52, 0xd2,
	0xd0, 0x58, 0x50, 0xd0, 0x94, 0x1c, 0x14, 0x94,
	0x90, 0x18, 0x10, 0x90, 0xd0, 0x58, 0x50, 0xd0,
	0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
	0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
	0xe1, 0x69, 0x61, 0xe1, 0xa5, 0x2d, 0x25, 0xa5,
	0xa1, 0x29, 0x21, 0xa1, 0xe1, 0x69, 0x61, 0xe1,
	0xc3, 0x4b, 0x43, 0xc3, 0x87, 0x0f, 0x07, 0x87,
	0x83, 0x0b, 0x03, 0x83, 0xc3, 0x4b, 0x43, 0xc3,
	0xc1, 0x49, 0x41, 0xc1, 0x85, 0x0d, 0x05, 0x85,
	0x81, 0x09, 0x01, 0x81, 0xc1, 0x49, 0x41, 0xc1,
	0xe1, 0x69, 0x61, 0xe1, 0xa5, 0x2d, 0x25, 0xa5,
	0xa1, 0x29, 0x21, 0xa1, 0xe1, 0x69, 0x61, 0xe1,
	0xe0, 0x68, 0x60, 0xe0, 0xa4, 0x2c, 0x24, 0xa4,
	0xa0, 0x28, 0x20, 0xa0, 0xe0, 0x68, 0x60, 0xe0,
	0xc2, 0x4a, 0x42, 0xc2, 0x86, 0x0e, 0x06, 0x86,
	0x82, 0x0a, 0x02, 0x82, 0xc2, 0x4a, 0x42, 0xc2,
	0xc0, 0x48, 0x40, 0xc0, 0x84, 0x0c, 0x04, 0x84,
	0x80, 0x08, 0x00, 0x80, 0xc0, 0x48, 0x40, 0xc0,
	0xe0, 0x68, 0x60, 0xe0, 0xa4, 0x2c, 0x24, 0xa4,
	0xa0, 0x28, 0x20, 0xa0, 0xe0, 0x68, 0x60, 0xe0,
	0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
	0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
	0xd2, 0x5a, 0x52, 0xd2, 0x96, 0x1e, 0x16, 0x96,
	0x92, 0x1a, 0x12, 0x92, 0xd2, 0x5a, 0x52, 0xd2,
	0xd0, 0x58, 0x50, 0xd0, 0x94, 0x1c, 0x14, 0x94,
	0x90, 0x18, 0x10, 0x90, 0xd0, 0x58, 0x50, 0xd0,
	0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
	0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
	};

	u8 c, err = 0;
	int i;

	for (i = 0; i < 2 * 13; i += 2) {
	err \|= biphase_tbl[p[i]] \| biphase_tbl[p[i + 1]];
	c = (biphase_tbl[p[i + 1]] & 0xf) \|
	((biphase_tbl[p[i]] & 0xf) << 4);
	dst[i / 2] = c;
	}

	return err & 0xf0;
	}

	void cx25840_vbi_setup(struct i2c_client *client)
	{
	v4l2_std_id std = cx25840_get_v4lstd(client);

	if (std & ~V4L2_STD_NTSC) {
	/* datasheet startup, step 8d */
	cx25840_write(client, 0x49f, 0x11);

	cx25840_write(client, 0x470, 0x84);
	cx25840_write(client, 0x471, 0x00);
	cx25840_write(client, 0x472, 0x2d);
	cx25840_write(client, 0x473, 0x5d);

	cx25840_write(client, 0x474, 0x24);
	cx25840_write(client, 0x475, 0x40);
	cx25840_write(client, 0x476, 0x24);
	cx25840_write(client, 0x477, 0x28);

	cx25840_write(client, 0x478, 0x1f);
	cx25840_write(client, 0x479, 0x02);

	if (std & V4L2_STD_SECAM) {
	cx25840_write(client, 0x47a, 0x80);
	cx25840_write(client, 0x47b, 0x00);
	cx25840_write(client, 0x47c, 0x5f);
	cx25840_write(client, 0x47d, 0x42);
	} else {
	cx25840_write(client, 0x47a, 0x90);
	cx25840_write(client, 0x47b, 0x20);
	cx25840_write(client, 0x47c, 0x63);
	cx25840_write(client, 0x47d, 0x82);
	}

	cx25840_write(client, 0x47e, 0x0a);
	cx25840_write(client, 0x47f, 0x01);
	} else {
	/* datasheet startup, step 8d */
	cx25840_write(client, 0x49f, 0x14);

	cx25840_write(client, 0x470, 0x7a);
	cx25840_write(client, 0x471, 0x00);
	cx25840_write(client, 0x472, 0x2d);
	cx25840_write(client, 0x473, 0x5b);

	cx25840_write(client, 0x474, 0x1a);
	cx25840_write(client, 0x475, 0x70);
	cx25840_write(client, 0x476, 0x1e);
	cx25840_write(client, 0x477, 0x1e);

	cx25840_write(client, 0x478, 0x1f);
	cx25840_write(client, 0x479, 0x02);
	cx25840_write(client, 0x47a, 0x50);
	cx25840_write(client, 0x47b, 0x66);

	cx25840_write(client, 0x47c, 0x1f);
	cx25840_write(client, 0x47d, 0x7c);
	cx25840_write(client, 0x47e, 0x08);
	cx25840_write(client, 0x47f, 0x00);
	}
	}

	int cx25840_vbi(struct i2c_client client, unsigned int cmd, void arg)
	{
	struct v4l2_format *fmt;
	struct v4l2_sliced_vbi_format *svbi;

	switch (cmd) {
	case VIDIOC_G_FMT:
	{
	static u16 lcr2vbi[] = {
	0, V4L2_SLICED_TELETEXT_B, 0, /* 1 */
	0, V4L2_SLICED_WSS_625, 0, /* 4 */
	V4L2_SLICED_CAPTION_525, /* 6 */
	0, 0, V4L2_SLICED_VPS, 0, 0, /* 9 */
	0, 0, 0, 0
	};
	int i;

	fmt = arg;
	if (fmt->type != V4L2_BUF_TYPE_SLICED_VBI_CAPTURE)
	return -EINVAL;
	svbi = &fmt->fmt.sliced;
	memset(svbi, 0, sizeof(*svbi));
	/* we're done if raw VBI is active */
	if ((cx25840_read(client, 0x404) & 0x10) == 0)
	break;

	for (i = 7; i <= 23; i++) {
	u8 v = cx25840_read(client, 0x424 + i - 7);

	svbi->service_lines[0][i] = lcr2vbi[v >> 4];
	svbi->service_lines[1][i] = lcr2vbi[v & 0xf];
	svbi->service_set \|=
	svbi->service_lines[0][i] \| svbi->service_lines[1][i];
	}
	break;
	}

	case VIDIOC_S_FMT:
	{
	int is_pal = !(cx25840_get_v4lstd(client) & V4L2_STD_NTSC);
	int vbi_offset = is_pal ? 1 : 0;
	int i, x;
	u8 lcr[24];

	fmt = arg;
	if (fmt->type != V4L2_BUF_TYPE_SLICED_VBI_CAPTURE)
	return -EINVAL;
	svbi = &fmt->fmt.sliced;
	if (svbi->service_set == 0) {
	/* raw VBI */
	memset(svbi, 0, sizeof(*svbi));

	/* Setup VBI */
	cx25840_vbi_setup(client);

	/* VBI Offset */
	cx25840_write(client, 0x47f, vbi_offset);
	cx25840_write(client, 0x404, 0x2e);
	break;
	}

	for (x = 0; x <= 23; x++)
	lcr[x] = 0x00;

	/* Setup VBI */
	cx25840_vbi_setup(client);

	/* Sliced VBI */
	cx25840_write(client, 0x404, 0x36); /* Ancillery data */
	cx25840_write(client, 0x406, 0x13);
	cx25840_write(client, 0x47f, vbi_offset);

	if (is_pal) {
	for (i = 0; i <= 6; i++)
	svbi->service_lines[0][i] =
	svbi->service_lines[1][i] = 0;
	} else {
	for (i = 0; i <= 9; i++)
	svbi->service_lines[0][i] =
	svbi->service_lines[1][i] = 0;

	for (i = 22; i <= 23; i++)
	svbi->service_lines[0][i] =
	svbi->service_lines[1][i] = 0;
	}

	for (i = 7; i <= 23; i++) {
	for (x = 0; x <= 1; x++) {
	switch (svbi->service_lines[1-x][i]) {
	case V4L2_SLICED_TELETEXT_B:
	lcr[i] \|= 1 << (4 * x);
	break;
	case V4L2_SLICED_WSS_625:
	lcr[i] \|= 4 << (4 * x);
	break;
	case V4L2_SLICED_CAPTION_525:
	lcr[i] \|= 6 << (4 * x);
	break;
	case V4L2_SLICED_VPS:
	lcr[i] \|= 9 << (4 * x);
	break;
	}
	}
	}

	for (x = 1, i = 0x424; i <= 0x434; i++, x++) {
	cx25840_write(client, i, lcr[6 + x]);
	}

	cx25840_write(client, 0x43c, 0x16);

	if (is_pal) {
	cx25840_write(client, 0x474, 0x2a);
	} else {
	cx25840_write(client, 0x474, 0x1a + 6);
	}
	break;
	}

	case VIDIOC_INT_DECODE_VBI_LINE:
	{
	struct v4l2_decode_vbi_line *vbi = arg;
	u8 *p = vbi->p;
	int id1, id2, l, err = 0;

	if (p[0] \|\| p[1] != 0xff \|\| p[2] != 0xff \|\|
	(p[3] != 0x55 && p[3] != 0x91)) {
	vbi->line = vbi->type = 0;
	break;
	}

	p += 4;
	id1 = p[-1];
	id2 = p[0] & 0xf;
	l = p[2] & 0x3f;
	l += 5;
	p += 4;

	switch (id2) {
	case 1:
	id2 = V4L2_SLICED_TELETEXT_B;
	break;
	case 4:
	id2 = V4L2_SLICED_WSS_625;
	break;
	case 6:
	id2 = V4L2_SLICED_CAPTION_525;
	err = !odd_parity(p[0]) \|\| !odd_parity(p[1]);
	break;
	case 9:
	id2 = V4L2_SLICED_VPS;
	if (decode_vps(p, p) != 0) {
	err = 1;
	}
	break;
	default:
	id2 = 0;
	err = 1;
	break;
	}

	vbi->type = err ? 0 : id2;
	vbi->line = err ? 0 : l;
	vbi->is_second_field = err ? 0 : (id1 == 0x55);
	vbi->p = p;
	break;
	}
	}

	return 0;
	}