drm/i915/debugfs: hdcp capability of a sink

Add a debugfs entry for providing the hdcp capabilities of the sink
connected to the HDCP capable connectors.

v2:
  Squashed the sink's hdcp capability into this patch. [Daniel]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1540286550-20399-4-git-send-email-ramalingam.c@intel.com

drivers/gpu/drm/i915/i915_debugfs.c

@@ -4977,6 +4977,28 @@ static int i915_panel_show(struct seq_file *m, void *data)
 }
 DEFINE_SHOW_ATTRIBUTE(i915_panel);
 
+static int i915_hdcp_sink_capability_show(struct seq_file *m, void *data)
+{
+	struct drm_connector *connector = m->private;
+	struct intel_connector *intel_connector = to_intel_connector(connector);
+
+	if (connector->status != connector_status_connected)
+		return -ENODEV;
+
+	/* HDCP is supported by connector */
+	if (!intel_connector->hdcp_shim)
+		return -EINVAL;
+
+	seq_printf(m, "%s:%d HDCP version: ", connector->name,
+		   connector->base.id);
+	seq_printf(m, "%s ", !intel_hdcp_capable(intel_connector) ?
+		   "None" : "HDCP1.4");
+	seq_puts(m, "\n");
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability);
+
 /**
  * i915_debugfs_connector_add - add i915 specific connector debugfs files
  * @connector: pointer to a registered drm_connector
@@ -5006,5 +5028,12 @@ int i915_debugfs_connector_add(struct drm_connector *connector)
 				    connector, &i915_psr_sink_status_fops);
 	}
 
+	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
+	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
+	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
+		debugfs_create_file("i915_hdcp_sink_capability", S_IRUGO, root,
+				    connector, &i915_hdcp_sink_capability_fops);
+	}
+
 	return 0;
 }

drivers/gpu/drm/i915/intel_drv.h

@@ -1296,6 +1296,12 @@ enc_to_dig_port(struct drm_encoder *encoder)
 		return NULL;
 }
 
+static inline struct intel_digital_port *
+conn_to_dig_port(struct intel_connector *connector)
+{
+	return enc_to_dig_port(&intel_attached_encoder(&connector->base)->base);
+}
+
 static inline struct intel_dp_mst_encoder *
 enc_to_mst(struct drm_encoder *encoder)
 {
@@ -1955,6 +1961,7 @@ 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);
+bool intel_hdcp_capable(struct intel_connector *connector);
 
 /* intel_psr.c */
 #define CAN_PSR(dev_priv) (HAS_PSR(dev_priv) && dev_priv->psr.sink_support)

drivers/gpu/drm/i915/intel_hdcp.c

@@ -51,6 +51,27 @@ int intel_hdcp_read_valid_bksv(struct intel_digital_port *intel_dig_port,
 	return 0;
 }
 
+/* Is HDCP1.4 capable on Platform and Sink */
+bool intel_hdcp_capable(struct intel_connector *connector)
+{
+	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
+	const struct intel_hdcp_shim *shim = connector->hdcp_shim;
+	bool capable = false;
+	u8 bksv[5];
+
+	if (!shim)
+		return capable;
+
+	if (shim->hdcp_capable) {
+		shim->hdcp_capable(intel_dig_port, &capable);
+	} else {
+		if (!intel_hdcp_read_valid_bksv(intel_dig_port, shim, bksv))
+			capable = true;
+	}
+
+	return capable;
+}
+
 static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
 				    const struct intel_hdcp_shim *shim)
 {
@@ -632,12 +653,6 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
 	return 0;
 }
 
-static
-struct intel_digital_port *conn_to_dig_port(struct intel_connector *connector)
-{
-	return enc_to_dig_port(&intel_attached_encoder(&connector->base)->base);
-}
-
 static int _intel_hdcp_disable(struct intel_connector *connector)
 {
 	struct drm_i915_private *dev_priv = connector->base.dev->dev_private;

drivers/gpu/drm/i915/intel_hdmi.c

@@ -2072,6 +2072,20 @@ static void chv_hdmi_pre_enable(struct intel_encoder *encoder,
 	chv_phy_release_cl2_override(encoder);
 }
 
+static int
+intel_hdmi_connector_register(struct drm_connector *connector)
+{
+	int ret;
+
+	ret = intel_connector_register(connector);
+	if (ret)
+		return ret;
+
+	i915_debugfs_connector_add(connector);
+
+	return ret;
+}
+
 static void intel_hdmi_destroy(struct drm_connector *connector)
 {
 	if (intel_attached_hdmi(connector)->cec_notifier)
@@ -2086,7 +2100,7 @@ static const struct drm_connector_funcs intel_hdmi_connector_funcs = {
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.atomic_get_property = intel_digital_connector_atomic_get_property,
 	.atomic_set_property = intel_digital_connector_atomic_set_property,
-	.late_register = intel_connector_register,
+	.late_register = intel_hdmi_connector_register,
 	.early_unregister = intel_connector_unregister,
 	.destroy = intel_hdmi_destroy,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,