[PATCH 4.14 145/165] media: v4l: vsp1: Fix display stalls when requesting too many inputs

From: Greg Kroah-Hartman
Date: Thu May 24 2018 - 05:52:42 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>

[ Upstream commit 5e3e4cb5e24b92773b194aa90066170b12133bc6 ]

Make sure we don't accept more inputs than the hardware can handle. This
is a temporary fix to avoid display stall, we need to instead allocate
the BRU or BRS to display pipelines dynamically based on the number of
planes they each use.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/media/platform/vsp1/vsp1_drm.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/drivers/media/platform/vsp1/vsp1_drm.c
+++ b/drivers/media/platform/vsp1/vsp1_drm.c
@@ -504,6 +504,15 @@ void vsp1_du_atomic_flush(struct device
struct vsp1_rwpf *rpf = vsp1->rpf[i];
unsigned int j;

+ /*
+ * Make sure we don't accept more inputs than the hardware can
+ * handle. This is a temporary fix to avoid display stall, we
+ * need to instead allocate the BRU or BRS to display pipelines
+ * dynamically based on the number of planes they each use.
+ */
+ if (pipe->num_inputs >= pipe->bru->source_pad)
+ pipe->inputs[i] = NULL;
+
if (!pipe->inputs[i])
continue;