V4L/DVB (8648): ivtv: improve CC support
- change the work-queue to a single threaded high prio workqueue
- use DMA instead of PIO for the sliced VBI data.
- remove some incorrect tests
- increase the internal VBI capture queue size for sliced VBI packets
- ignore duplicate VBI lines
With these changes it should finally be possible to get reliable closed
captions.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/ivtv/ivtv-irq.c b/drivers/media/video/ivtv/ivtv-irq.c
index fba150a..34f3ab8 100644
--- a/drivers/media/video/ivtv/ivtv-irq.c
+++ b/drivers/media/video/ivtv/ivtv-irq.c
@@ -76,6 +76,13 @@
DEFINE_WAIT(wait);
+ if (test_and_clear_bit(IVTV_F_I_WORK_INITED, &itv->i_flags)) {
+ struct sched_param param = { .sched_priority = 99 };
+
+ /* This thread must use the FIFO scheduler as it
+ is realtime sensitive. */
+ sched_setscheduler(current, SCHED_FIFO, ¶m);
+ }
if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags))
ivtv_pio_work_handler(itv);
@@ -678,34 +685,14 @@
static void ivtv_irq_enc_vbi_cap(struct ivtv *itv)
{
- struct ivtv_stream *s_mpg = &itv->streams[IVTV_ENC_STREAM_TYPE_MPG];
u32 data[CX2341X_MBOX_MAX_DATA];
struct ivtv_stream *s;
IVTV_DEBUG_HI_IRQ("ENC START VBI CAP\n");
s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
- /* If more than two VBI buffers are pending, then
- clear the old ones and start with this new one.
- This can happen during transition stages when MPEG capturing is
- started, but the first interrupts haven't arrived yet. During
- that period VBI requests can accumulate without being able to
- DMA the data. Since at most four VBI DMA buffers are available,
- we just drop the old requests when there are already three
- requests queued. */
- if (s->sg_pending_size > 2) {
- struct ivtv_buffer *buf;
- list_for_each_entry(buf, &s->q_predma.list, list)
- ivtv_buf_sync_for_cpu(s, buf);
- ivtv_queue_move(s, &s->q_predma, NULL, &s->q_free, 0);
- s->sg_pending_size = 0;
- }
- /* if we can append the data, and the MPEG stream isn't capturing,
- then start a DMA request for just the VBI data. */
- if (!stream_enc_dma_append(s, data) &&
- !test_bit(IVTV_F_S_STREAMING, &s_mpg->s_flags)) {
+ if (!stream_enc_dma_append(s, data))
set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
- }
}
static void ivtv_irq_dec_vbi_reinsert(struct ivtv *itv)