linux-kernel - [PATCH 2/2] drm/dp: Drop open-coded drm_dp_is_branch() in drm_dp_read_downstream

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Date:   Fri, 30 Apr 2021 18:34:28 -0400
From:   Lyude Paul <lyude@...hat.com>
To:     intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org
Cc:     Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        linux-kernel@...r.kernel.org (open list)
Subject: [PATCH 2/2] drm/dp: Drop open-coded drm_dp_is_branch() in drm_dp_read_downstream_info()

Noticed this while fixing another issue in drm_dp_read_downstream_info(),
the open coded DP_DOWNSTREAMPORT_PRESENT check here just duplicates what we
already do in drm_dp_is_branch(), so just get rid of it.

Signed-off-by: Lyude Paul <lyude@...hat.com>
---
 drivers/gpu/drm/drm_dp_helper.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 27c8c5bdf7d9..0f84df8798ab 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -677,9 +677,7 @@ int drm_dp_read_downstream_info(struct drm_dp_aux *aux,
 	memset(downstream_ports, 0, DP_MAX_DOWNSTREAM_PORTS);
 
 	/* No downstream info to read */
-	if (!drm_dp_is_branch(dpcd) ||
-	    dpcd[DP_DPCD_REV] < DP_DPCD_REV_10 ||
-	    !(dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT))
+	if (!drm_dp_is_branch(dpcd) || dpcd[DP_DPCD_REV] < DP_DPCD_REV_10)
 		return 0;
 
 	/* Some branches advertise having 0 downstream ports, despite also advertising they have a
-- 
2.30.2