Commit 272acbca authored by Louis Chauvet's avatar Louis Chauvet Committed by Luca Ceresoli
Browse files

drm/vkms: Allow to configure multiple connectors via configfs 



Create a default subgroup at
/config/vkms/connectors to allow to create as many connectors as
required.

Tested-by: default avatarMark Yacoub <markyacoub@google.com>
Reviewed-by: default avatarLouis Chauvet <louis.chauvet@bootlin.com>
Reviewed-by: default avatarHarry Wentland <harry.wentland@amd.com>
Reviewed-by: default avatarLuca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: default avatarLouis Chauvet <louis.chauvet@bootlin.com>
Co-developed-by: default avatarJosé Expósito <jose.exposito89@gmail.com>
Signed-off-by: default avatarJosé Expósito <jose.exposito89@gmail.com>
Link: https://lore.kernel.org/r/20251016175618.10051-11-jose.exposito89@gmail.com


Signed-off-by: default avatarLuca Ceresoli <luca.ceresoli@bootlin.com>
parent fad1138b

Documentation/gpu/vkms.rst

+6 −0
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ By default, the instance is disabled:: 
And directories are created for each configurable item of the display pipeline::



  tree /config/vkms/my-vkms

  ├── connectors

  ├── crtcs

  ├── enabled

  ├── encoders
@@ -103,6 +104,10 @@ Next, create one or more encoders:: 


  sudo mkdir /config/vkms/my-vkms/encoders/encoder0



Last but not least, create one or more connectors::



  sudo mkdir /config/vkms/my-vkms/connectors/connector0



To finish the configuration, link the different pipeline items::



  sudo ln -s /config/vkms/my-vkms/crtcs/crtc0 /config/vkms/my-vkms/planes/plane0/possible_crtcs
@@ -127,6 +132,7 @@ And removing the top level directory and its subdirectories:: 
  sudo rmdir /config/vkms/my-vkms/planes/*

  sudo rmdir /config/vkms/my-vkms/crtcs/*

  sudo rmdir /config/vkms/my-vkms/encoders/*

  sudo rmdir /config/vkms/my-vkms/connectors/*

  sudo rmdir /config/vkms/my-vkms



Testing With IGT

drivers/gpu/drm/vkms/vkms_configfs.c

+87 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ static bool is_configfs_registered; 
 * @planes_group: Default subgroup of @group at "/config/vkms/planes"

 * @crtcs_group: Default subgroup of @group at "/config/vkms/crtcs"

 * @encoders_group: Default subgroup of @group at "/config/vkms/encoders"

 * @connectors_group: Default subgroup of @group at "/config/vkms/connectors"

 * @lock: Lock used to project concurrent access to the configuration attributes

 * @config: Protected by @lock. Configuration of the VKMS device

 * @enabled: Protected by @lock. The device is created or destroyed when this
@@ -29,6 +30,7 @@ struct vkms_configfs_device { 
	struct config_group planes_group;

	struct config_group crtcs_group;

	struct config_group encoders_group;

	struct config_group connectors_group;



	struct mutex lock;

	struct vkms_config *config;
@@ -81,6 +83,20 @@ struct vkms_configfs_encoder { 
	struct vkms_config_encoder *config;

};



/**

 * struct vkms_configfs_connector - Configfs representation of a connector

 *

 * @group: Top level configuration group that represents a connector.

 * Initialized when a new directory is created under "/config/vkms/connectors"

 * @dev: The vkms_configfs_device this connector belongs to

 * @config: Configuration of the VKMS connector

 */

struct vkms_configfs_connector {

	struct config_group group;

	struct vkms_configfs_device *dev;

	struct vkms_config_connector *config;

};



#define device_item_to_vkms_configfs_device(item) \

	container_of(to_config_group((item)), struct vkms_configfs_device, \

		     group)
@@ -106,6 +122,10 @@ struct vkms_configfs_encoder { 
	container_of(to_config_group((item)), struct vkms_configfs_encoder, \

		     possible_crtcs_group)



#define connector_item_to_vkms_configfs_connector(item) \

	container_of(to_config_group((item)), struct vkms_configfs_connector, \

		     group)



static ssize_t crtc_writeback_show(struct config_item *item, char *page)

{

	struct vkms_configfs_crtc *crtc;
@@ -485,6 +505,69 @@ static const struct config_item_type encoder_group_type = { 
	.ct_owner	= THIS_MODULE,

};



static void connector_release(struct config_item *item)

{

	struct vkms_configfs_connector *connector;

	struct mutex *lock;



	connector = connector_item_to_vkms_configfs_connector(item);

	lock = &connector->dev->lock;



	scoped_guard(mutex, lock) {

		vkms_config_destroy_connector(connector->config);

		kfree(connector);

	}

}



static struct configfs_item_operations connector_item_operations = {

	.release	= &connector_release,

};



static const struct config_item_type connector_item_type = {

	.ct_item_ops	= &connector_item_operations,

	.ct_owner	= THIS_MODULE,

};



static struct config_group *make_connector_group(struct config_group *group,

						 const char *name)

{

	struct vkms_configfs_device *dev;

	struct vkms_configfs_connector *connector;



	dev = child_group_to_vkms_configfs_device(group);



	scoped_guard(mutex, &dev->lock) {

		if (dev->enabled)

			return ERR_PTR(-EBUSY);



		connector = kzalloc(sizeof(*connector), GFP_KERNEL);

		if (!connector)

			return ERR_PTR(-ENOMEM);



		connector->dev = dev;



		connector->config = vkms_config_create_connector(dev->config);

		if (IS_ERR(connector->config)) {

			kfree(connector);

			return ERR_CAST(connector->config);

		}



		config_group_init_type_name(&connector->group, name,

					    &connector_item_type);

	}



	return &connector->group;

}



static struct configfs_group_operations connectors_group_operations = {

	.make_group	= &make_connector_group,

};



static const struct config_item_type connector_group_type = {

	.ct_group_ops	= &connectors_group_operations,

	.ct_owner	= THIS_MODULE,

};



static ssize_t device_enabled_show(struct config_item *item, char *page)

{

	struct vkms_configfs_device *dev;
@@ -592,6 +675,10 @@ static struct config_group *make_device_group(struct config_group *group, 
				    &encoder_group_type);

	configfs_add_default_group(&dev->encoders_group, &dev->group);



	config_group_init_type_name(&dev->connectors_group, "connectors",

				    &connector_group_type);

	configfs_add_default_group(&dev->connectors_group, &dev->group);



	return &dev->group;

}