[RFC PATCH 11/13] staging: mmal-vchiq: Reset buffers_with_vpu on port_enable

From: Maarten Vanraes <maarten@rmail.be>
To: Raspberry Pi Kernel Maintenance <kernel-list@raspberrypi.com>,
	linux-media@vger.kernel.org
Cc: Kieran Bingham <kbingham@kernel.org>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Umang Jain <umang.jain@ideasonboard.com>,
	Dave Stevenson <dave.stevenson@raspberrypi.com>,
	Maarten Vanraes <maarten@rmail.be>
Subject: [RFC PATCH 11/13] staging: mmal-vchiq: Reset buffers_with_vpu on port_enable
Date: Sun,  3 Mar 2024 16:10:06 +0100	[thread overview]
Message-ID: <20240303152635.2762696-12-maarten@rmail.be> (raw)
In-Reply-To: <20240303152635.2762696-1-maarten@rmail.be>

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.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maarten Vanraes <maarten@rmail.be>
---
 drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
index 479b8114dcdb..14ecb8e5e2ee 100644
--- a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
+++ b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
@@ -1483,6 +1483,8 @@ 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;
-- 
2.41.0

