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 <ly...@redhat.com>
Reviewed-by: Sean Paul <s...@poorly.run>
---
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);
--
2.26.2
