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>

6 files changed, 15 insertions, 25 deletions

diff --git a/drivers/media/video/ivtv/ivtv-driver.c b/drivers/media/video/ivtv/ivtv-driver.c
index aea1664948ce..4afc7ea07e86 100644
--- a/drivers/media/video/ivtv/ivtv-driver.c
+++ b/drivers/media/video/ivtv/ivtv-driver.c
@@ -688,7 +688,7 @@ static int __devinit ivtv_init_struct1(struct ivtv *itv)
         spin_lock_init(&itv->lock);
         spin_lock_init(&itv->dma_reg_lock);
 
-        itv->irq_work_queues = create_workqueue(itv->name);
+        itv->irq_work_queues = create_singlethread_workqueue(itv->name);
         if (itv->irq_work_queues == NULL) {
                 IVTV_ERR("Could not create ivtv workqueue\n");
                 return -1;
diff --git a/drivers/media/video/ivtv/ivtv-driver.h b/drivers/media/video/ivtv/ivtv-driver.h
index ab287b48fc2b..2ceb5227637c 100644
--- a/drivers/media/video/ivtv/ivtv-driver.h
+++ b/drivers/media/video/ivtv/ivtv-driver.h
@@ -251,6 +251,7 @@ struct ivtv_mailbox_data {
 #define IVTV_F_I_DEC_PAUSED        20   /* the decoder is paused */
 #define IVTV_F_I_INITED            21   /* set after first open */
 #define IVTV_F_I_FAILED            22   /* set if first open failed */
+#define IVTV_F_I_WORK_INITED       23   /* worker thread was initialized */
 
 /* Event notifications */
 #define IVTV_F_I_EV_DEC_STOPPED    28   /* decoder stopped event */
diff --git a/drivers/media/video/ivtv/ivtv-irq.c b/drivers/media/video/ivtv/ivtv-irq.c
index fba150a6cd23..34f3ab827858 100644
--- a/drivers/media/video/ivtv/ivtv-irq.c
+++ b/drivers/media/video/ivtv/ivtv-irq.c
@@ -76,6 +76,13 @@ void ivtv_irq_work_handler(struct work_struct *work)
 
         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, &param);
+        }
         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_start_cap(struct ivtv *itv)
 
 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)
diff --git a/drivers/media/video/ivtv/ivtv-queue.h b/drivers/media/video/ivtv/ivtv-queue.h
index 7cfc0c9ab050..476556afd39a 100644
--- a/drivers/media/video/ivtv/ivtv-queue.h
+++ b/drivers/media/video/ivtv/ivtv-queue.h
@@ -23,7 +23,7 @@
 #define IVTV_QUEUE_H
 
 #define IVTV_DMA_UNMAPPED       ((u32) -1)
-#define SLICED_VBI_PIO 1
+#define SLICED_VBI_PIO 0
 
 /* ivtv_buffer utility functions */
 
diff --git a/drivers/media/video/ivtv/ivtv-streams.c b/drivers/media/video/ivtv/ivtv-streams.c
index 54d2023b26c4..730e85d86fc8 100644
--- a/drivers/media/video/ivtv/ivtv-streams.c
+++ b/drivers/media/video/ivtv/ivtv-streams.c
@@ -363,7 +363,7 @@ static void ivtv_vbi_setup(struct ivtv *itv)
         /* Every X number of frames a VBI interrupt arrives (frames as in 25 or 30 fps) */
         data[1] = 1;
         /* The VBI frames are stored in a ringbuffer with this size (with a VBI frame as unit) */
-        data[2] = raw ? 4 : 8;
+        data[2] = raw ? 4 : 4 * (itv->vbi.raw_size / itv->vbi.enc_size);
         /* The start/stop codes determine which VBI lines end up in the raw VBI data area.
            The codes are from table 24 in the saa7115 datasheet. Each raw/sliced/video line
            is framed with codes FF0000XX where XX is the SAV/EAV (Start/End of Active Video)
diff --git a/drivers/media/video/ivtv/ivtv-vbi.c b/drivers/media/video/ivtv/ivtv-vbi.c
index 71798f0da27f..1ce9deb1104f 100644
--- a/drivers/media/video/ivtv/ivtv-vbi.c
+++ b/drivers/media/video/ivtv/ivtv-vbi.c
@@ -293,6 +293,7 @@ static u32 compress_sliced_buf(struct ivtv *itv, u32 line, u8 *buf, u32 size, u8
         u32 line_size = itv->vbi.sliced_decoder_line_size;
         struct v4l2_decode_vbi_line vbi;
         int i;
+        unsigned lines = 0;
 
         /* find the first valid line */
         for (i = 0; i < size; i++, buf++) {
@@ -313,7 +314,8 @@ static u32 compress_sliced_buf(struct ivtv *itv, u32 line, u8 *buf, u32 size, u8
                 }
                 vbi.p = p + 4;
                 itv->video_dec_func(itv, VIDIOC_INT_DECODE_VBI_LINE, &vbi);
-                if (vbi.type) {
+                if (vbi.type && !(lines & (1 << vbi.line))) {
+                        lines |= 1 << vbi.line;
                         itv->vbi.sliced_data[line].id = vbi.type;
                         itv->vbi.sliced_data[line].field = vbi.is_second_field;
                         itv->vbi.sliced_data[line].line = vbi.line;