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| author | Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> | 2018-03-14 05:49:09 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2018-03-22 13:22:39 +0300 |
| commit | 6a8ffa8b4c519419f7b926904f02c8d1fec5b488 (patch) | |
| tree | 31bc8ee1491cfc91d0f0952f27a6432d4648fa7f /drivers/media/platform/rcar-vin/rcar-dma.c | |
| parent | 579260a5ef48703570acf56c0ceb63aea720784b (diff) | |
| download | linux-6a8ffa8b4c519419f7b926904f02c8d1fec5b488.tar.xz | |
media: rcar-vin: allocate a scratch buffer at stream start
Before starting a capture, allocate a scratch buffer which can be used
by the driver to give to the hardware if no buffers are available from
userspace. The buffer is not used in this patch but prepares for future
refactoring where the scratch buffer can be used to avoid the need to
fallback on single capture mode if userspace can't queue buffers as fast
as the VIN driver consumes them.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media/platform/rcar-vin/rcar-dma.c')
| -rw-r--r-- | drivers/media/platform/rcar-vin/rcar-dma.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c index 23fdff7a7370..1f91b056188e 100644 --- a/drivers/media/platform/rcar-vin/rcar-dma.c +++ b/drivers/media/platform/rcar-vin/rcar-dma.c @@ -1076,6 +1076,17 @@ static int rvin_start_streaming(struct vb2_queue *vq, unsigned int count) unsigned long flags; int ret; + /* Allocate scratch buffer. */ + vin->scratch = dma_alloc_coherent(vin->dev, vin->format.sizeimage, + &vin->scratch_phys, GFP_KERNEL); + if (!vin->scratch) { + spin_lock_irqsave(&vin->qlock, flags); + return_all_buffers(vin, VB2_BUF_STATE_QUEUED); + spin_unlock_irqrestore(&vin->qlock, flags); + vin_err(vin, "Failed to allocate scratch buffer\n"); + return -ENOMEM; + } + sd = vin_to_source(vin); v4l2_subdev_call(sd, video, s_stream, 1); @@ -1091,6 +1102,10 @@ static int rvin_start_streaming(struct vb2_queue *vq, unsigned int count) spin_unlock_irqrestore(&vin->qlock, flags); + if (ret) + dma_free_coherent(vin->dev, vin->format.sizeimage, vin->scratch, + vin->scratch_phys); + return ret; } @@ -1141,6 +1156,10 @@ static void rvin_stop_streaming(struct vb2_queue *vq) /* disable interrupts */ rvin_disable_interrupts(vin); + + /* Free scratch buffer. */ + dma_free_coherent(vin->dev, vin->format.sizeimage, vin->scratch, + vin->scratch_phys); } static const struct vb2_ops rvin_qops = { |