Re: [PATCH v5 09/20] drm/i915/dp: Extract drm_dp_read_mst_cap()

On Wed, 26 Aug 2020, Lyude Paul lyude@redhat.com wrote:

Just a tiny drive-by cleanup, we can consolidate i915's code for checking for MST support into a helper to be shared across drivers.

v5:

• Drop !!()
• Move drm_dp_has_mst() out of header
• Change name from drm_dp_has_mst() to drm_dp_read_mst_cap()

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Sean Paul sean@poorly.run

Reviewed-by: Jani Nikula jani.nikula@intel.com

---

drivers/gpu/drm/drm_dp_mst_topology.c | 22 ++++++++++++++++++++++ drivers/gpu/drm/i915/display/intel_dp.c | 18 ++---------------- include/drm/drm_dp_mst_helper.h | 3 +-- 3 files changed, 25 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 67dd72ea200e0..17dbed0a9800d 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -3486,6 +3486,28 @@ static int drm_dp_get_vc_payload_bw(u8 dp_link_bw, u8 dp_link_count) return dp_link_bw * dp_link_count / 2; }

+/**

• • drm_dp_read_mst_cap() - check whether or not a sink supports MST
• • @aux: The DP AUX channel to use
• • @dpcd: A cached copy of the DPCD capabilities for this sink
• • Returns: %True if the sink supports MST, %false otherwise
• */

+bool drm_dp_read_mst_cap(struct drm_dp_aux *aux,

• 	 const u8 dpcd[DP_RECEIVER_CAP_SIZE])
  

+{

• u8 mstm_cap;
• if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_12)

• return false;
  

• if (drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &mstm_cap) != 1)

• return false;
  

• return mstm_cap & DP_MST_CAP;

+} +EXPORT_SYMBOL(drm_dp_read_mst_cap);

/**

• drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
• @mgr: manager to set state for

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 79c27f91f42c0..4c7314b7a84e4 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -4699,20 +4699,6 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp) return true; }

-static bool -intel_dp_sink_can_mst(struct intel_dp *intel_dp) -{

• u8 mstm_cap;
• if (intel_dp->dpcd[DP_DPCD_REV] < 0x12)

• return false;
  

• if (drm_dp_dpcd_readb(&intel_dp->aux, DP_MSTM_CAP, &mstm_cap) != 1)

• return false;
  

• return mstm_cap & DP_MST_CAP;

-}

static bool intel_dp_can_mst(struct intel_dp *intel_dp) { @@ -4720,7 +4706,7 @@ intel_dp_can_mst(struct intel_dp *intel_dp)

return i915->params.enable_dp_mst && intel_dp->can_mst &&

• intel_dp_sink_can_mst(intel_dp);
  

• drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd);
  

}

static void @@ -4729,7 +4715,7 @@ intel_dp_configure_mst(struct intel_dp *intel_dp) struct drm_i915_private *i915 = dp_to_i915(intel_dp); struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;

• bool sink_can_mst = intel_dp_sink_can_mst(intel_dp);

• bool sink_can_mst = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd);

  drm_dbg_kms(&i915->drm, "[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam: %s\n",

diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h index 8b9eb4db3381c..6ae5860d8644e 100644 --- a/include/drm/drm_dp_mst_helper.h +++ b/include/drm/drm_dp_mst_helper.h @@ -728,10 +728,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,

void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr);

+bool drm_dp_read_mst_cap(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE]); int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state);

int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled);