drm: Add Content protection type property

This patch adds a DRM ENUM property to the selected connectors.
This property is used for mentioning the protected content's type
from userspace to kernel HDCP authentication.

Type of the stream is decided by the protected content providers.
Type 0 content can be rendered on any HDCP protected display wires.
But Type 1 content can be rendered only on HDCP2.2 protected paths.

So when a userspace sets this property to Type 1 and starts the HDCP
enable, kernel will honour it only if HDCP2.2 authentication is through
for type 1. Else HDCP enable will be failed.

Pekka have completed the Weston DRM-backend review in
https://gitlab.freedesktop.org/wayland/weston/merge_requests/48
and the UAPI for HDCP 2.2 looks good.

The userspace is accepted in Weston.

v2:
  cp_content_type is replaced with content_protection_type [daniel]
  check at atomic_set_property is removed [Maarten]
v3:
  %s/content_protection_type/hdcp_content_type [Pekka]
v4:
  property is created for the first requested connector and then reused.
	[Danvet]
v5:
  kernel doc nits addressed [Daniel]
  Rebased as part of patch reordering.
v6:
  Kernel docs are modified [pekka]
v7:
  More details in Kernel docs. [pekka]
v8:
  Few more clarification into kernel doc of content type [pekka]
v9:
  Small fixes in coding style.
v10:
  Moving DRM_MODE_HDCP_CONTENT_TYPEx definition to drm_hdcp.h [pekka]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/320957/?series=57232&rev=14

1 files changed, 35 insertions, 1 deletions

diff --git a/drivers/gpu/drm/drm_hdcp.c b/drivers/gpu/drm/drm_hdcp.c
index cd837bd409f7..ce235fd1c844 100644
--- a/drivers/gpu/drm/drm_hdcp.c
+++ b/drivers/gpu/drm/drm_hdcp.c
@@ -344,23 +344,41 @@ static struct drm_prop_enum_list drm_cp_enum_list[] = {
 };
 DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
 
+static struct drm_prop_enum_list drm_hdcp_content_type_enum_list[] = {
+	{ DRM_MODE_HDCP_CONTENT_TYPE0, "HDCP Type0" },
+	{ DRM_MODE_HDCP_CONTENT_TYPE1, "HDCP Type1" },
+};
+DRM_ENUM_NAME_FN(drm_get_hdcp_content_type_name,
+		 drm_hdcp_content_type_enum_list)
+
 /**
  * drm_connector_attach_content_protection_property - attach content protection
  * property
  *
  * @connector: connector to attach CP property on.
+ * @hdcp_content_type: is HDCP Content Type property needed for connector
  *
  * This is used to add support for content protection on select connectors.
  * Content Protection is intentionally vague to allow for different underlying
  * technologies, however it is most implemented by HDCP.
  *
+ * When hdcp_content_type is true enum property called HDCP Content Type is
+ * created (if it is not already) and attached to the connector.
+ *
+ * This property is used for sending the protected content's stream type
+ * from userspace to kernel on selected connectors. Protected content provider
+ * will decide their type of their content and declare the same to kernel.
+ *
+ * Content type will be used during the HDCP 2.2 authentication.
+ * Content type will be set to &drm_connector_state.hdcp_content_type.
+ *
  * The content protection will be set to &drm_connector_state.content_protection
  *
  * Returns:
  * Zero on success, negative errno on failure.
  */
 int drm_connector_attach_content_protection_property(
-		struct drm_connector *connector)
+		struct drm_connector *connector, bool hdcp_content_type)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_property *prop =
@@ -377,6 +395,22 @@ int drm_connector_attach_content_protection_property(
 				   DRM_MODE_CONTENT_PROTECTION_UNDESIRED);
 	dev->mode_config.content_protection_property = prop;
 
+	if (!hdcp_content_type)
+		return 0;
+
+	prop = dev->mode_config.hdcp_content_type_property;
+	if (!prop)
+		prop = drm_property_create_enum(dev, 0, "HDCP Content Type",
+					drm_hdcp_content_type_enum_list,
+					ARRAY_SIZE(
+					drm_hdcp_content_type_enum_list));
+	if (!prop)
+		return -ENOMEM;
+
+	drm_object_attach_property(&connector->base, prop,
+				   DRM_MODE_HDCP_CONTENT_TYPE0);
+	dev->mode_config.hdcp_content_type_property = prop;
+
 	return 0;
 }
 EXPORT_SYMBOL(drm_connector_attach_content_protection_property);