Re: [PATCH 03/42] drm/drm_dp_mst_topology: Remove set but never used variable 'len'

From: Daniel Vetter
Date: Tue Nov 17 2020 - 12:29:31 EST


On Mon, Nov 16, 2020 at 05:40:33PM +0000, Lee Jones wrote:
> Fixes the following W=1 kernel build warning(s):
>
> drivers/gpu/drm/drm_dp_mst_topology.c: In function ‘drm_dp_send_query_stream_enc_status’:
> drivers/gpu/drm/drm_dp_mst_topology.c:3263:6: warning: variable ‘len’ set but not used [-Wunused-but-set-variable]
>
> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
> Cc: Maxime Ripard <mripard@xxxxxxxxxx>
> Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
> Cc: David Airlie <airlied@xxxxxxxx>
> Cc: Daniel Vetter <daniel@xxxxxxxx>
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>

Going to apply this, but I noticed that the return value of the
build_query_stream_enc_status() is pointless. Can you pls follow up with
an additional patch to change that to void?

Thanks, Daniel

> ---
> drivers/gpu/drm/drm_dp_mst_topology.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> index e875425336406..0401b2f475002 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -3260,7 +3260,7 @@ int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr,
> {
> struct drm_dp_sideband_msg_tx *txmsg;
> u8 nonce[7];
> - int len, ret;
> + int ret;
>
> txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
> if (!txmsg)
> @@ -3281,7 +3281,7 @@ int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr,
> */
> txmsg->dst = mgr->mst_primary;
>
> - len = build_query_stream_enc_status(txmsg, port->vcpi.vcpi, nonce);
> + build_query_stream_enc_status(txmsg, port->vcpi.vcpi, nonce);
>
> drm_dp_queue_down_tx(mgr, txmsg);
>
> --
> 2.25.1
>

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch