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| author | Lyude Paul <lyude@redhat.com> | 2021-05-08 00:42:09 +0300 |
|---|---|---|
| committer | Lyude Paul <lyude@redhat.com> | 2021-05-10 23:26:07 +0300 |
| commit | 208d8b9d26f5fd0f7c0fcaa460873bbd6b5bebfa (patch) | |
| tree | b8e238b66ae4cab6f34cc8feecd22755fd7d2792 /drivers/gpu/drm/drm_dp_helper.c | |
| parent | 04dfe19a5ed683e91d8285df5be1dbde2f2f39af (diff) | |
| download | linux-208d8b9d26f5fd0f7c0fcaa460873bbd6b5bebfa.tar.xz | |
drm/dp: Fix bogus DPCD version check in drm_dp_read_downstream_info()
Ville pointed this out to me when fixing some issues in
drm_dp_read_downstream_info() - the DPCD version check here is bogus as
there's no DisplayPort versions prior to 1.0. The original code from i915
that this was extracted from actually did:
dpcd[DP_DPCD_REV] == DP_DPCD_REV_10
Which is correct, and somehow got missed when extracting this function. So
let's fix this. Note that as far as I'm aware, I don't think this fixes any
actual issues users are hitting.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210507214209.554866-1-lyude@redhat.com
Diffstat (limited to 'drivers/gpu/drm/drm_dp_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 0f84df8798ab..55b53df6ce34 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -677,7 +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) + 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 |