HW revision is mandatory field for DisplayPort branch devices. This is defined in DPCD register field 0x509. v2: move drm_dp_ds_revision structure to be part of drm_dp_link structure (Daniel) Signed-off-by: Mika Kahola <mika.kahola@xxxxxxxxx> --- drivers/gpu/drm/drm_dp_helper.c | 27 +++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_drv.h | 1 + include/drm/drm_dp_helper.h | 9 +++++++++ 3 files changed, 37 insertions(+) diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 75b2873..5fecdc1 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -514,6 +514,33 @@ int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE], EXPORT_SYMBOL(drm_dp_downstream_max_bpc); /** + * drm_dp_downstream_hw_rev() - read DP branch device HW revision + * @aux: DisplayPort AUX channel + * + * Returns 0 on succes or negative error code on failure + */ +int drm_dp_downstream_hw_rev(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + struct drm_dp_aux *aux, struct drm_dp_link *link) +{ + uint8_t tmp; + int err; + + if (!(dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT)) + return -EINVAL; + + err = drm_dp_dpcd_read(aux, DP_BRANCH_HW_REV, &tmp, 1); + + if (err < 0) + return err; + + link->ds_hw_rev.major = (tmp & 0xf0) >> 4; + link->ds_hw_rev.minor = tmp & 0xf; + + return 0; +} +EXPORT_SYMBOL(drm_dp_downstream_hw_rev); + +/** * drm_dp_downstream_id() - identify branch device * @aux: DisplayPort AUX channel * diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index e74d851..a6eccf5 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -865,6 +865,7 @@ struct intel_dp { uint8_t num_sink_rates; int sink_rates[DP_MAX_SUPPORTED_RATES]; struct drm_dp_aux aux; + struct drm_dp_link link; uint8_t train_set[4]; int panel_power_up_delay; int panel_power_down_delay; diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 8e1fe58..1127948 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -446,6 +446,7 @@ #define DP_SINK_OUI 0x400 #define DP_BRANCH_OUI 0x500 #define DP_BRANCH_ID 0x503 +#define DP_BRANCH_HW_REV 0x509 #define DP_SET_POWER 0x600 # define DP_SET_POWER_D0 0x1 @@ -803,11 +804,17 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, */ #define DP_LINK_CAP_ENHANCED_FRAMING (1 << 0) +struct drm_dp_ds_revision { + int major; + int minor; +}; + struct drm_dp_link { unsigned char revision; unsigned int rate; unsigned int num_lanes; unsigned long capabilities; + struct drm_dp_ds_revision ds_hw_rev; }; int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link); @@ -819,6 +826,8 @@ int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE], const u8 port_cap[4]); int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]); +int drm_dp_downstream_hw_rev(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + struct drm_dp_aux *aux, struct drm_dp_link *link); void drm_dp_aux_init(struct drm_dp_aux *aux); int drm_dp_aux_register(struct drm_dp_aux *aux); -- 1.9.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel