[PATCH v3 1/6] platform/raspberrypi: vchiq-mmal: Reset buffers_with_vpu on port_enable

[Jai Luthra]

From: Dave Stevenson <dave.stevenson at raspberrypi.com>

Should we go through the timeout failure case with port_disable
not returning all buffers for whatever reason, the
buffers_with_vpu counter gets left at a non-zero value, which
will cause reference counting issues should the instance be
reused.

Reset the count when the port is enabled again, but before
any buffers have been sent to the VPU.

Fixes: 70ec64ccdaac ("staging: bcm2835-camera: Ensure all buffers are returned on disable")
Cc: stable at vger.kernel.org
Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
Signed-off-by: Jai Luthra <jai.luthra at ideasonboard.com>
---
 drivers/platform/raspberrypi/vchiq-mmal/mmal-vchiq.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/platform/raspberrypi/vchiq-mmal/mmal-vchiq.c b/drivers/platform/raspberrypi/vchiq-mmal/mmal-vchiq.c
index c89c16fb8b33..918c30d84ba0 100644
--- a/drivers/platform/raspberrypi/vchiq-mmal/mmal-vchiq.c
+++ b/drivers/platform/raspberrypi/vchiq-mmal/mmal-vchiq.c
@@ -1364,6 +1364,8 @@ static int port_enable(struct vchiq_mmal_instance *instance,
 
 	port->enabled = true;
 
+	atomic_set(&port->buffers_with_vpu, 0);
+
 	if (port->buffer_cb) {
 		/* send buffer headers to videocore */
 		hdr_count = 1;

-- 
2.54.0