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| author | Mika Kahola <mika.kahola@intel.com> | 2016-09-09 14:10:51 +0300 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2016-09-15 14:50:11 +0300 |
| commit | 266d783baaf5f34a5bea3b56489f091451a89767 (patch) | |
| tree | 759ed36c1c0d179c820d39b03b0eb5975bde3be1 /drivers/gpu/drm/drm_dp_helper.c | |
| parent | 7529d6af1cd16b0ecd286a1bf6ceee5328ab9809 (diff) | |
| download | linux-266d783baaf5f34a5bea3b56489f091451a89767.tar.bz2 | |
drm: Read DP branch device id
Read DisplayPort branch device id string.
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473419458-17080-6-git-send-email-mika.kahola@intel.com
Diffstat (limited to 'drivers/gpu/drm/drm_dp_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 57c61d126a56..7b3a638725d9 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -513,6 +513,18 @@ int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE], } EXPORT_SYMBOL(drm_dp_downstream_max_bpc); +/** + * drm_dp_downstream_id() - identify branch device + * @aux: DisplayPort AUX channel + * + * Returns branch device id on success or NULL on failure + */ +int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]) +{ + return drm_dp_dpcd_read(aux, DP_BRANCH_ID, id, 6); +} +EXPORT_SYMBOL(drm_dp_downstream_id); + /* * I2C-over-AUX implementation */ |