[PATCH v5 20/40] drm/i915: Check HDCP 1.4 and 2.2 link on CP_IRQ

[Ramalingam C]

On DP HDCP1.4 and 2.2, when CP_IRQ is received, start the link
integrity check for the HDCP version that is enabled.

v2:
  Rebased. Function name is changed.
v3:
  No Changes.
v4:
  No Changes.
v5:
  No Changes.

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
cc: Sean Paul <seanpaul at chromium.org>
---
 drivers/gpu/drm/i915/intel_dp.c   |  2 +-
 drivers/gpu/drm/i915/intel_drv.h  |  2 +-
 drivers/gpu/drm/i915/intel_hdcp.c | 31 ++++++++++++++++++++++++++++++-
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 7467e7b3f2df..a6ba27ef20ae 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4484,7 +4484,7 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
 		if (sink_irq_vector & DP_AUTOMATED_TEST_REQUEST)
 			intel_dp_handle_test_request(intel_dp);
 		if (sink_irq_vector & DP_CP_IRQ)
-			intel_hdcp_check_link(intel_dp->attached_connector);
+			intel_hdcp_handle_cp_irq(intel_dp->attached_connector);
 		if (sink_irq_vector & DP_SINK_SPECIFIC_IRQ)
 			DRM_DEBUG_DRIVER("Sink specific irq unhandled\n");
 	}
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 7624388eecd5..875657fd7d3c 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1965,8 +1965,8 @@ int intel_hdcp_init(struct intel_connector *connector,
 		    bool hdcp2_supported);
 int intel_hdcp_enable(struct intel_connector *connector);
 int intel_hdcp_disable(struct intel_connector *connector);
-int intel_hdcp_check_link(struct intel_connector *connector);
 bool is_hdcp_supported(struct drm_i915_private *dev_priv, enum port port);
+void intel_hdcp_handle_cp_irq(struct intel_connector *connector);
 
 /* intel_psr.c */
 #define CAN_PSR(dev_priv) (HAS_PSR(dev_priv) && dev_priv->psr.sink_support)
diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
index 790f4a9f4793..b035274785c8 100644
--- a/drivers/gpu/drm/i915/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/intel_hdcp.c
@@ -32,6 +32,7 @@ int intel_hdcp_read_valid_bksv(struct intel_digital_port *intel_dig_port,
 			       const struct intel_hdcp_shim *shim, u8 *bksv);
 static
 struct intel_digital_port *conn_to_dig_port(struct intel_connector *connector);
+static int intel_hdcp_check_link(struct intel_connector *connector);
 
 static bool panel_supports_hdcp(struct intel_connector *connector)
 {
@@ -80,6 +81,26 @@ static inline bool intel_hdcp2_capable(struct intel_connector *connector)
 		panel_supports_hdcp2(connector));
 }
 
+static inline bool intel_hdcp_in_force(struct intel_connector *connector)
+{
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	enum port port = connector->encoder->port;
+	u32 reg;
+
+	reg = I915_READ(PORT_HDCP_STATUS(port));
+	return reg & (HDCP_STATUS_AUTH | HDCP_STATUS_ENC);
+}
+
+static inline bool intel_hdcp2_in_force(struct intel_connector *connector)
+{
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	enum port port = connector->encoder->port;
+	u32 reg;
+
+	reg = I915_READ(HDCP2_STATUS_DDI(port));
+	return reg & (LINK_ENCRYPTION_STATUS | LINK_AUTH_STATUS);
+}
+
 static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
 				    const struct intel_hdcp_shim *shim)
 {
@@ -939,7 +960,7 @@ void intel_hdcp_atomic_check(struct drm_connector *connector,
 }
 
 /* Implements Part 3 of the HDCP authorization procedure */
-int intel_hdcp_check_link(struct intel_connector *connector)
+static int intel_hdcp_check_link(struct intel_connector *connector)
 {
 	struct intel_hdcp *hdcp = &connector->hdcp;
 	struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
@@ -2011,3 +2032,11 @@ static void intel_hdcp2_check_work(struct work_struct *work)
 		schedule_delayed_work(&hdcp->hdcp2_check_work,
 				      DRM_HDCP2_CHECK_PERIOD_MS);
 }
+
+void intel_hdcp_handle_cp_irq(struct intel_connector *connector)
+{
+	if (intel_hdcp_in_force(connector))
+		intel_hdcp_check_link(connector);
+	else if (intel_hdcp2_in_force(connector))
+		intel_hdcp2_check_link(connector);
+}
-- 
2.7.4