[PATCH v4 1/6] platform/raspberrypi: vchiq-mmal: Reset buffers_with_vpu on port_enable

From: Dave Stevenson <dave.stevenson@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@vger.kernel.org
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Jai Luthra <jai.luthra@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;

-- 
2.55.0