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path: root/drivers/media/video/bttv-vbi.c
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Diffstat (limited to 'drivers/media/video/bttv-vbi.c')
-rw-r--r--drivers/media/video/bttv-vbi.c57
1 files changed, 22 insertions, 35 deletions
diff --git a/drivers/media/video/bttv-vbi.c b/drivers/media/video/bttv-vbi.c
index f4f58c60f152..72afdd64b882 100644
--- a/drivers/media/video/bttv-vbi.c
+++ b/drivers/media/video/bttv-vbi.c
@@ -31,6 +31,12 @@
#include <asm/io.h>
#include "bttvp.h"
+/* Offset from line sync pulse leading edge (0H) in 1 / sampling_rate:
+ bt8x8 /HRESET pulse starts at 0H and has length 64 / fCLKx1 (E|O_VTC
+ HSFMT = 0). VBI_HDELAY (always 0) is an offset from the trailing edge
+ of /HRESET in 1 / fCLKx1, and the sampling_rate tvnorm->Fsc is fCLKx2. */
+#define VBI_OFFSET ((64 + 0) * 2)
+
#define VBI_DEFLINES 16
#define VBI_MAXLINES 32
@@ -163,40 +169,30 @@ void bttv_vbi_setlines(struct bttv_fh *fh, struct bttv *btv, int lines)
void bttv_vbi_try_fmt(struct bttv_fh *fh, struct v4l2_format *f)
{
const struct bttv_tvnorm *tvnorm;
- u32 start0,start1;
- s32 count0,count1,count;
+ s64 count0,count1,count;
tvnorm = &bttv_tvnorms[fh->btv->tvnorm];
f->type = V4L2_BUF_TYPE_VBI_CAPTURE;
f->fmt.vbi.sampling_rate = tvnorm->Fsc;
f->fmt.vbi.samples_per_line = 2048;
f->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY;
- f->fmt.vbi.offset = 244;
+ f->fmt.vbi.offset = VBI_OFFSET;
f->fmt.vbi.flags = 0;
- switch (fh->btv->tvnorm) {
- case 1: /* NTSC */
- start0 = 10;
- start1 = 273;
- break;
- case 0: /* PAL */
- case 2: /* SECAM */
- default:
- start0 = 7;
- start1 = 320;
- }
- count0 = (f->fmt.vbi.start[0] + f->fmt.vbi.count[0]) - start0;
- count1 = (f->fmt.vbi.start[1] + f->fmt.vbi.count[1]) - start1;
- count = max(count0,count1);
- if (count > VBI_MAXLINES)
- count = VBI_MAXLINES;
- if (count < 1)
- count = 1;
+ /* s64 to prevent overflow. */
+ count0 = (s64) f->fmt.vbi.start[0] + f->fmt.vbi.count[0]
+ - tvnorm->vbistart[0];
+ count1 = (s64) f->fmt.vbi.start[1] + f->fmt.vbi.count[1]
+ - tvnorm->vbistart[1];
+ count = clamp (max (count0, count1), 1LL, (s64) VBI_MAXLINES);
- f->fmt.vbi.start[0] = start0;
- f->fmt.vbi.start[1] = start1;
+ f->fmt.vbi.start[0] = tvnorm->vbistart[0];
+ f->fmt.vbi.start[1] = tvnorm->vbistart[1];
f->fmt.vbi.count[0] = count;
f->fmt.vbi.count[1] = count;
+
+ f->fmt.vbi.reserved[0] = 0;
+ f->fmt.vbi.reserved[1] = 0;
}
void bttv_vbi_get_fmt(struct bttv_fh *fh, struct v4l2_format *f)
@@ -209,21 +205,12 @@ void bttv_vbi_get_fmt(struct bttv_fh *fh, struct v4l2_format *f)
f->fmt.vbi.sampling_rate = tvnorm->Fsc;
f->fmt.vbi.samples_per_line = 2048;
f->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY;
- f->fmt.vbi.offset = 244;
+ f->fmt.vbi.offset = VBI_OFFSET;
+ f->fmt.vbi.start[0] = tvnorm->vbistart[0];
+ f->fmt.vbi.start[1] = tvnorm->vbistart[1];
f->fmt.vbi.count[0] = fh->lines;
f->fmt.vbi.count[1] = fh->lines;
f->fmt.vbi.flags = 0;
- switch (fh->btv->tvnorm) {
- case 1: /* NTSC */
- f->fmt.vbi.start[0] = 10;
- f->fmt.vbi.start[1] = 273;
- break;
- case 0: /* PAL */
- case 2: /* SECAM */
- default:
- f->fmt.vbi.start[0] = 7;
- f->fmt.vbi.start[1] = 319;
- }
}
/* ----------------------------------------------------------------------- */