Commit bb5a45d4 authored by Ramalingam C's avatar Ramalingam C
Browse files

drm/hdcp: update content protection property with uevent 

drm function is defined and exported to update a connector's
content protection property state and to generate a uevent along
with it.

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:
  Update only when state is different from old one.
v3:
  KDoc is added [Daniel]
v4:
  KDoc is extended bit more [pekka]
v5:
  Uevent usage is documented at kdoc of "Content Protection" also
  [pekka]

Signed-off-by: default avatarRamalingam C <ramalingam.c@intel.com>
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: default avatarPekka Paalanen <pekka.paalanen@collabora.com>
Acked-by: default avatarJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/320963/?series=57232&rev=14
parent 6fe2ce06

drivers/gpu/drm/drm_connector.c

+13 −4
Original line number Diff line number Diff line
@@ -983,10 +983,19 @@ static const struct drm_prop_enum_list hdmi_colorspaces[] = { 
 *	- If the state is DESIRED, kernel should attempt to re-authenticate the

 *	  link whenever possible. This includes across disable/enable, dpms,

 *	  hotplug, downstream device changes, link status failures, etc..

 *	- Userspace is responsible for polling the property to determine when

 *	  the value transitions from ENABLED to DESIRED. This signifies the link

 *	  is no longer protected and userspace should take appropriate action

 *	  (whatever that might be).

 *	- Kernel sends uevent with the connector id and property id through

 *	  @drm_hdcp_update_content_protection, upon below kernel triggered

 *	  scenarios:

 *		DESIRED -> ENABLED	(authentication success)

 *		ENABLED -> DESIRED	(termination of authentication)

 *	- Please note no uevents for userspace triggered property state changes,

 *	  which can't fail such as

 *		DESIRED/ENABLED -> UNDESIRED

 *		UNDESIRED -> DESIRED

 *	- Userspace is responsible for polling the property or listen to uevents

 *	  to determine when the value transitions from ENABLED to DESIRED.

 *	  This signifies the link is no longer protected and userspace should

 *	  take appropriate action (whatever that might be).

 *

 * HDCP Content Type:

 *	This Enum property is used by the userspace to declare the content type

drivers/gpu/drm/drm_hdcp.c

+34 −0
Original line number Diff line number Diff line
@@ -374,6 +374,10 @@ DRM_ENUM_NAME_FN(drm_get_hdcp_content_type_name, 
 *

 * The content protection will be set to &drm_connector_state.content_protection

 *

 * When kernel triggered content protection state change like DESIRED->ENABLED

 * and ENABLED->DESIRED, will use drm_hdcp_update_content_protection() to update

 * the content protection state of a connector.

 *

 * Returns:

 * Zero on success, negative errno on failure.

 */
@@ -414,3 +418,33 @@ int drm_connector_attach_content_protection_property( 
	return 0;

}

EXPORT_SYMBOL(drm_connector_attach_content_protection_property);



/**

 * drm_hdcp_update_content_protection - Updates the content protection state

 * of a connector

 *

 * @connector: drm_connector on which content protection state needs an update

 * @val: New state of the content protection property

 *

 * This function can be used by display drivers, to update the kernel triggered

 * content protection state changes of a drm_connector such as DESIRED->ENABLED

 * and ENABLED->DESIRED. No uevent for DESIRED->UNDESIRED or ENABLED->UNDESIRED,

 * as userspace is triggering such state change and kernel performs it without

 * fail.This function update the new state of the property into the connector's

 * state and generate an uevent to notify the userspace.

 */

void drm_hdcp_update_content_protection(struct drm_connector *connector,

					u64 val)

{

	struct drm_device *dev = connector->dev;

	struct drm_connector_state *state = connector->state;



	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));

	if (state->content_protection == val)

		return;



	state->content_protection = val;

	drm_sysfs_connector_status_event(connector,

				 dev->mode_config.content_protection_property);

}

EXPORT_SYMBOL(drm_hdcp_update_content_protection);

include/drm/drm_hdcp.h

+2 −0
Original line number Diff line number Diff line
@@ -292,6 +292,8 @@ bool drm_hdcp_check_ksvs_revoked(struct drm_device *dev, 
				 u8 *ksvs, u32 ksv_count);

int drm_connector_attach_content_protection_property(

		struct drm_connector *connector, bool hdcp_content_type);

void drm_hdcp_update_content_protection(struct drm_connector *connector,

					u64 val);



/* Content Type classification for HDCP2.2 vs others */

#define DRM_MODE_HDCP_CONTENT_TYPE0		0

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