Commit 107fe904 authored by Rajat Jain's avatar Rajat Jain Committed by Hans de Goede
Browse files

drm/connector: Add support for privacy-screen properties (v4) 



Add support for generic electronic privacy screen properties, that
can be added by systems that have an integrated EPS.

Changes in v2 (Hans de Goede)
- Create 2 properties, "privacy-screen sw-state" and
  "privacy-screen hw-state", to deal with devices where the OS might be
  locked out of making state changes
- Write kerneldoc explaining how the 2 properties work together, what
  happens when changes to the state are made outside of the DRM code's
  control, etc.

Changes in v3 (Hans de Goede)
- Some small tweaks to the kerneldoc describing the 2 properties

Changes in v4 (Hans de Goede)
- Change the "Enabled, locked" and "Disabled, locked" hw-state enum value
  names to "Enabled-locked" and "Disabled-locked". The xrandr command shows
  all possible enum values separated by commas in its output, so having a
  comma in an enum name is not a good idea.
- Do not add a privacy_screen_hw_state member to drm_connector_state
  since this property is immutable its value must be directly stored in the
  obj->properties->values array

Signed-off-by: default avatarRajat Jain <rajatja@google.com>
Acked-by: default avatarPekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: default avatarMario Limonciello <Mario.limonciello@dell.com>
Reviewed-by: default avatarEmil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Co-developed-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-2-hdegoede@redhat.com
parent b3ec8cdf

Documentation/gpu/drm-kms.rst

+2 −0
Original line number Diff line number Diff line
@@ -506,6 +506,8 @@ Property Types and Blob Property Support 
.. kernel-doc:: drivers/gpu/drm/drm_property.c

   :export:



.. _standard_connector_properties:



Standard Connector Properties

-----------------------------

drivers/gpu/drm/drm_atomic_uapi.c

+4 −0
Original line number Diff line number Diff line
@@ -797,6 +797,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector, 
						   fence_ptr);

	} else if (property == connector->max_bpc_property) {

		state->max_requested_bpc = val;

	} else if (property == connector->privacy_screen_sw_state_property) {

		state->privacy_screen_sw_state = val;

	} else if (connector->funcs->atomic_set_property) {

		return connector->funcs->atomic_set_property(connector,

				state, property, val);
@@ -874,6 +876,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector, 
		*val = 0;

	} else if (property == connector->max_bpc_property) {

		*val = state->max_requested_bpc;

	} else if (property == connector->privacy_screen_sw_state_property) {

		*val = state->privacy_screen_sw_state;

	} else if (connector->funcs->atomic_get_property) {

		return connector->funcs->atomic_get_property(connector,

				state, property, val);

drivers/gpu/drm/drm_connector.c

+101 −0
Original line number Diff line number Diff line
@@ -1271,6 +1271,46 @@ static const struct drm_prop_enum_list dp_colorspaces[] = { 
 *	For DVI-I and TVout there is also a matching property "select subconnector"

 *	allowing to switch between signal types.

 *	DP subconnector corresponds to a downstream port.

 *

 * privacy-screen sw-state, privacy-screen hw-state:

 *	These 2 optional properties can be used to query the state of the

 *	electronic privacy screen that is available on some displays; and in

 *	some cases also control the state. If a driver implements these

 *	properties then both properties must be present.

 *

 *	"privacy-screen hw-state" is read-only and reflects the actual state

 *	of the privacy-screen, possible values: "Enabled", "Disabled,

 *	"Enabled-locked", "Disabled-locked". The locked states indicate

 *	that the state cannot be changed through the DRM API. E.g. there

 *	might be devices where the firmware-setup options, or a hardware

 *	slider-switch, offer always on / off modes.

 *

 *	"privacy-screen sw-state" can be set to change the privacy-screen state

 *	when not locked. In this case the driver must update the hw-state

 *	property to reflect the new state on completion of the commit of the

 *	sw-state property. Setting the sw-state property when the hw-state is

 *	locked must be interpreted by the driver as a request to change the

 *	state to the set state when the hw-state becomes unlocked. E.g. if

 *	"privacy-screen hw-state" is "Enabled-locked" and the sw-state

 *	gets set to "Disabled" followed by the user unlocking the state by

 *	changing the slider-switch position, then the driver must set the

 *	state to "Disabled" upon receiving the unlock event.

 *

 *	In some cases the privacy-screen's actual state might change outside of

 *	control of the DRM code. E.g. there might be a firmware handled hotkey

 *	which toggles the actual state, or the actual state might be changed

 *	through another userspace API such as writing /proc/acpi/ibm/lcdshadow.

 *	In this case the driver must update both the hw-state and the sw-state

 *	to reflect the new value, overwriting any pending state requests in the

 *	sw-state. Any pending sw-state requests are thus discarded.

 *

 *	Note that the ability for the state to change outside of control of

 *	the DRM master process means that userspace must not cache the value

 *	of the sw-state. Caching the sw-state value and including it in later

 *	atomic commits may lead to overriding a state change done through e.g.

 *	a firmware handled hotkey. Therefor userspace must not include the

 *	privacy-screen sw-state in an atomic commit unless it wants to change

 *	its value.

 */



int drm_connector_create_standard_properties(struct drm_device *dev)
@@ -2365,6 +2405,67 @@ int drm_connector_set_panel_orientation_with_quirk( 
}

EXPORT_SYMBOL(drm_connector_set_panel_orientation_with_quirk);



static const struct drm_prop_enum_list privacy_screen_enum[] = {

	{ PRIVACY_SCREEN_DISABLED,		"Disabled" },

	{ PRIVACY_SCREEN_ENABLED,		"Enabled" },

	{ PRIVACY_SCREEN_DISABLED_LOCKED,	"Disabled-locked" },

	{ PRIVACY_SCREEN_ENABLED_LOCKED,	"Enabled-locked" },

};



/**

 * drm_connector_create_privacy_screen_properties - create the drm connecter's

 *    privacy-screen properties.

 * @connector: connector for which to create the privacy-screen properties

 *

 * This function creates the "privacy-screen sw-state" and "privacy-screen

 * hw-state" properties for the connector. They are not attached.

 */

void

drm_connector_create_privacy_screen_properties(struct drm_connector *connector)

{

	if (connector->privacy_screen_sw_state_property)

		return;



	/* Note sw-state only supports the first 2 values of the enum */

	connector->privacy_screen_sw_state_property =

		drm_property_create_enum(connector->dev, DRM_MODE_PROP_ENUM,

				"privacy-screen sw-state",

				privacy_screen_enum, 2);



	connector->privacy_screen_hw_state_property =

		drm_property_create_enum(connector->dev,

				DRM_MODE_PROP_IMMUTABLE | DRM_MODE_PROP_ENUM,

				"privacy-screen hw-state",

				privacy_screen_enum,

				ARRAY_SIZE(privacy_screen_enum));

}

EXPORT_SYMBOL(drm_connector_create_privacy_screen_properties);



/**

 * drm_connector_attach_privacy_screen_properties - attach the drm connecter's

 *    privacy-screen properties.

 * @connector: connector on which to attach the privacy-screen properties

 *

 * This function attaches the "privacy-screen sw-state" and "privacy-screen

 * hw-state" properties to the connector. The initial state of both is set

 * to "Disabled".

 */

void

drm_connector_attach_privacy_screen_properties(struct drm_connector *connector)

{

	if (!connector->privacy_screen_sw_state_property)

		return;



	drm_object_attach_property(&connector->base,

				   connector->privacy_screen_sw_state_property,

				   PRIVACY_SCREEN_DISABLED);



	drm_object_attach_property(&connector->base,

				   connector->privacy_screen_hw_state_property,

				   PRIVACY_SCREEN_DISABLED);

}

EXPORT_SYMBOL(drm_connector_attach_privacy_screen_properties);



int drm_connector_set_obj_prop(struct drm_mode_object *obj,

				    struct drm_property *property,

				    uint64_t value)

include/drm/drm_connector.h

+44 −0
Original line number Diff line number Diff line
@@ -320,6 +320,30 @@ struct drm_monitor_range_info { 
	u8 max_vfreq;

};



/**

 * enum drm_privacy_screen_status - privacy screen status

 *

 * This enum is used to track and control the state of the integrated privacy

 * screen present on some display panels, via the "privacy-screen sw-state"

 * and "privacy-screen hw-state" properties. Note the _LOCKED enum values

 * are only valid for the "privacy-screen hw-state" property.

 *

 * @PRIVACY_SCREEN_DISABLED:

 *  The privacy-screen on the panel is disabled

 * @PRIVACY_SCREEN_ENABLED:

 *  The privacy-screen on the panel is enabled

 * @PRIVACY_SCREEN_DISABLED_LOCKED:

 *  The privacy-screen on the panel is disabled and locked (cannot be changed)

 * @PRIVACY_SCREEN_ENABLED_LOCKED:

 *  The privacy-screen on the panel is enabled and locked (cannot be changed)

 */

enum drm_privacy_screen_status {

	PRIVACY_SCREEN_DISABLED = 0,

	PRIVACY_SCREEN_ENABLED,

	PRIVACY_SCREEN_DISABLED_LOCKED,

	PRIVACY_SCREEN_ENABLED_LOCKED,

};



/*

 * This is a consolidated colorimetry list supported by HDMI and

 * DP protocol standard. The respective connectors will register
@@ -781,6 +805,12 @@ struct drm_connector_state { 
	 */

	u8 max_bpc;



	/**

	 * @privacy_screen_sw_state: See :ref:`Standard Connector

	 * Properties<standard_connector_properties>`

	 */

	enum drm_privacy_screen_status privacy_screen_sw_state;



	/**

	 * @hdr_output_metadata:

	 * DRM blob property for HDR output metadata
@@ -1409,6 +1439,18 @@ struct drm_connector { 
	 */

	struct drm_property *max_bpc_property;



	/**

	 * @privacy_screen_sw_state_property: Optional atomic property for the

	 * connector to control the integrated privacy screen.

	 */

	struct drm_property *privacy_screen_sw_state_property;



	/**

	 * @privacy_screen_hw_state_property: Optional atomic property for the

	 * connector to report the actual integrated privacy screen state.

	 */

	struct drm_property *privacy_screen_hw_state_property;



#define DRM_CONNECTOR_POLL_HPD (1 << 0)

#define DRM_CONNECTOR_POLL_CONNECT (1 << 1)

#define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)
@@ -1732,6 +1774,8 @@ int drm_connector_set_panel_orientation_with_quirk( 
	int width, int height);

int drm_connector_attach_max_bpc_property(struct drm_connector *connector,

					  int min, int max);

void drm_connector_create_privacy_screen_properties(struct drm_connector *conn);

void drm_connector_attach_privacy_screen_properties(struct drm_connector *conn);



/**

 * struct drm_tile_group - Tile group metadata