[PATCH 1/3] drm/i915/pps: Add helpers to lock PPS for AUX transfers

[Imre Deak]

Factor out from the DP AUX transfer function the logic to lock/unlock
the Panel Power Sequencer state and enable/disable the VDD power
required for the AUX transfer, adding these to helpers in intel_pps.c .
This prepares for a follow-up change making these steps dependent on the
platform and output type.

Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp_aux.c | 16 ++----------
 drivers/gpu/drm/i915/display/intel_pps.c    | 29 ++++++++++++++++++++-
 drivers/gpu/drm/i915/display/intel_pps.h    |  3 ++-
 3 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux.c b/drivers/gpu/drm/i915/display/intel_dp_aux.c
index ec27bbd70bcf0..bf5ccfa24ca0b 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_aux.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_aux.c
@@ -272,15 +272,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 	aux_domain = intel_aux_power_domain(dig_port);
 
 	aux_wakeref = intel_display_power_get(display, aux_domain);
-	pps_wakeref = intel_pps_lock(intel_dp);
-
-	/*
-	 * We will be called with VDD already enabled for dpcd/edid/oui reads.
-	 * In such cases we want to leave VDD enabled and it's up to upper layers
-	 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
-	 * ourselves.
-	 */
-	vdd = intel_pps_vdd_on_unlocked(intel_dp);
+	pps_wakeref = intel_pps_lock_for_aux(intel_dp, &vdd);
 
 	/*
 	 * dp aux is extremely sensitive to irq latency, hence request the
@@ -289,8 +281,6 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 	 */
 	cpu_latency_qos_update_request(&intel_dp->pm_qos, 0);
 
-	intel_pps_check_power_unlocked(intel_dp);
-
 	/*
 	 * FIXME PSR should be disabled here to prevent
 	 * it using the same AUX CH simultaneously
@@ -427,10 +417,8 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 out:
 	cpu_latency_qos_update_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
 
-	if (vdd)
-		intel_pps_vdd_off_unlocked(intel_dp, false);
+	intel_pps_unlock_for_aux(intel_dp, pps_wakeref, vdd);
 
-	intel_pps_unlock(intel_dp, pps_wakeref);
 	intel_display_power_put_async(display, aux_domain, aux_wakeref);
 out_unlock:
 	intel_digital_port_unlock(encoder);
diff --git a/drivers/gpu/drm/i915/display/intel_pps.c b/drivers/gpu/drm/i915/display/intel_pps.c
index 617ce49931726..3c078fd53fbfa 100644
--- a/drivers/gpu/drm/i915/display/intel_pps.c
+++ b/drivers/gpu/drm/i915/display/intel_pps.c
@@ -571,7 +571,7 @@ static bool edp_have_panel_vdd(struct intel_dp *intel_dp)
 	return intel_de_read(display, _pp_ctrl_reg(intel_dp)) & EDP_FORCE_VDD;
 }
 
-void intel_pps_check_power_unlocked(struct intel_dp *intel_dp)
+static void intel_pps_check_power_unlocked(struct intel_dp *intel_dp)
 {
 	struct intel_display *display = to_intel_display(intel_dp);
 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
@@ -955,6 +955,33 @@ void intel_pps_vdd_off(struct intel_dp *intel_dp)
 		intel_pps_vdd_off_unlocked(intel_dp, false);
 }
 
+intel_wakeref_t intel_pps_lock_for_aux(struct intel_dp *intel_dp, bool *vdd_ref)
+{
+	intel_wakeref_t wakeref;
+
+	wakeref = intel_pps_lock(intel_dp);
+
+	/*
+	 * We will be called with VDD already enabled for dpcd/edid/oui reads.
+	 * In such cases we want to leave VDD enabled and it's up to upper layers
+	 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
+	 * ourselves.
+	 */
+	*vdd_ref = intel_pps_vdd_on_unlocked(intel_dp);
+
+	intel_pps_check_power_unlocked(intel_dp);
+
+	return wakeref;
+}
+
+void intel_pps_unlock_for_aux(struct intel_dp *intel_dp, intel_wakeref_t wakeref, bool vdd_ref)
+{
+	if (vdd_ref)
+		intel_pps_vdd_off_unlocked(intel_dp, false);
+
+	intel_pps_unlock(intel_dp, wakeref);
+}
+
 void intel_pps_on_unlocked(struct intel_dp *intel_dp)
 {
 	struct intel_display *display = to_intel_display(intel_dp);
diff --git a/drivers/gpu/drm/i915/display/intel_pps.h b/drivers/gpu/drm/i915/display/intel_pps.h
index c83007152f07d..4390d05892325 100644
--- a/drivers/gpu/drm/i915/display/intel_pps.h
+++ b/drivers/gpu/drm/i915/display/intel_pps.h
@@ -31,10 +31,11 @@ bool intel_pps_vdd_on_unlocked(struct intel_dp *intel_dp);
 void intel_pps_vdd_off_unlocked(struct intel_dp *intel_dp, bool sync);
 void intel_pps_on_unlocked(struct intel_dp *intel_dp);
 void intel_pps_off_unlocked(struct intel_dp *intel_dp);
-void intel_pps_check_power_unlocked(struct intel_dp *intel_dp);
 
 void intel_pps_vdd_on(struct intel_dp *intel_dp);
 void intel_pps_vdd_off(struct intel_dp *intel_dp);
+intel_wakeref_t intel_pps_lock_for_aux(struct intel_dp *intel_dp, bool *vdd_ref);
+void intel_pps_unlock_for_aux(struct intel_dp *intel_dp, intel_wakeref_t wakeref, bool vdd_ref);
 void intel_pps_on(struct intel_dp *intel_dp);
 void intel_pps_off(struct intel_dp *intel_dp);
 void intel_pps_vdd_off_sync(struct intel_dp *intel_dp);
-- 
2.44.2