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authorHans Verkuil <hans.verkuil@cisco.com>2014-04-11 05:02:29 -0300
committerMauro Carvalho Chehab <m.chehab@samsung.com>2014-04-16 18:54:30 -0300
commit5f26f2501b81190b60a0b72d611668fb6a59dd24 (patch)
treea46059b71f8e277b4fcef7c5e5a0d2b2ae148159 /Documentation/video4linux
parentb050b29e071a0b11262ad513700ab073f58c45b2 (diff)
downloadkernel-5f26f2501b81190b60a0b72d611668fb6a59dd24.tar.gz
[media] v4l2-pci-skeleton.c: fix alternate field handling
For interlaced HDTV timings the correct field setting is FIELD_ALTERNATE, not INTERLACED. Update this template driver accordingly: - add check for the invalid combination of read() and FIELD_ALTERNATE. - in the interrupt handler set v4l2_buffer field to alternating TOP and BOTTOM. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Diffstat (limited to 'Documentation/video4linux')
-rw-r--r--Documentation/video4linux/v4l2-pci-skeleton.c39
1 files changed, 28 insertions, 11 deletions
diff --git a/Documentation/video4linux/v4l2-pci-skeleton.c b/Documentation/video4linux/v4l2-pci-skeleton.c
index 3a1c0d2dafce..80251dc2c6cf 100644
--- a/Documentation/video4linux/v4l2-pci-skeleton.c
+++ b/Documentation/video4linux/v4l2-pci-skeleton.c
@@ -77,7 +77,8 @@ struct skeleton {
spinlock_t qlock;
struct list_head buf_list;
- unsigned int sequence;
+ unsigned field;
+ unsigned sequence;
};
struct skel_buffer {
@@ -124,7 +125,7 @@ static const struct v4l2_dv_timings_cap skel_timings_cap = {
* Interrupt handler: typically interrupts happen after a new frame has been
* captured. It is the job of the handler to remove the new frame from the
* internal list and give it back to the vb2 framework, updating the sequence
- * counter and timestamp at the same time.
+ * counter, field and timestamp at the same time.
*/
static irqreturn_t skeleton_irq(int irq, void *dev_id)
{
@@ -139,8 +140,15 @@ static irqreturn_t skeleton_irq(int irq, void *dev_id)
spin_lock(&skel->qlock);
list_del(&new_buf->list);
spin_unlock(&skel->qlock);
- new_buf->vb.v4l2_buf.sequence = skel->sequence++;
v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp);
+ new_buf->vb.v4l2_buf.sequence = skel->sequence++;
+ new_buf->vb.v4l2_buf.field = skel->field;
+ if (skel->format.field == V4L2_FIELD_ALTERNATE) {
+ if (skel->field == V4L2_FIELD_BOTTOM)
+ skel->field = V4L2_FIELD_TOP;
+ else if (skel->field == V4L2_FIELD_TOP)
+ skel->field = V4L2_FIELD_BOTTOM;
+ }
vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_DONE);
}
#endif
@@ -160,6 +168,17 @@ static int queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
{
struct skeleton *skel = vb2_get_drv_priv(vq);
+ skel->field = skel->format.field;
+ if (skel->field == V4L2_FIELD_ALTERNATE) {
+ /*
+ * You cannot use read() with FIELD_ALTERNATE since the field
+ * information (TOP/BOTTOM) cannot be passed back to the user.
+ */
+ if (vb2_fileio_is_active(q))
+ return -EINVAL;
+ skel->field = V4L2_FIELD_TOP;
+ }
+
if (vq->num_buffers + *nbuffers < 3)
*nbuffers = 3 - vq->num_buffers;
@@ -173,10 +192,7 @@ static int queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
/*
* Prepare the buffer for queueing to the DMA engine: check and set the
- * payload size and fill in the field. Note: if the format's field is
- * V4L2_FIELD_ALTERNATE, then vb->v4l2_buf.field should be set in the
- * interrupt handler since that's usually where you know if the TOP or
- * BOTTOM field has been captured.
+ * payload size.
*/
static int buffer_prepare(struct vb2_buffer *vb)
{
@@ -190,7 +206,6 @@ static int buffer_prepare(struct vb2_buffer *vb)
}
vb2_set_plane_payload(vb, 0, size);
- vb->v4l2_buf.field = skel->format.field;
return 0;
}
@@ -319,10 +334,12 @@ static void skeleton_fill_pix_format(struct skeleton *skel,
/* HDMI input */
pix->width = skel->timings.bt.width;
pix->height = skel->timings.bt.height;
- if (skel->timings.bt.interlaced)
- pix->field = V4L2_FIELD_INTERLACED;
- else
+ if (skel->timings.bt.interlaced) {
+ pix->field = V4L2_FIELD_ALTERNATE;
+ pix->height /= 2;
+ } else {
pix->field = V4L2_FIELD_NONE;
+ }
pix->colorspace = V4L2_COLORSPACE_REC709;
}