On 18/02/25 - 18:08, José Expósito wrote:
> Create a default subgroup at /config/vkms/encoders to allow to create as
> many encoders as required.
>
> Co-developed-by: Louis Chauvet <[email protected]>
> Signed-off-by: Louis Chauvet <[email protected]>
> Signed-off-by: José Expósito <[email protected]>
> ---
> Documentation/gpu/vkms.rst | 6 ++
> drivers/gpu/drm/vkms/vkms_configfs.c | 99 ++++++++++++++++++++++++++++
> 2 files changed, 105 insertions(+)
>
> diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
> index 3c9d72bdb65a..24f40128e8f3 100644
> --- a/Documentation/gpu/vkms.rst
> +++ b/Documentation/gpu/vkms.rst
> @@ -76,6 +76,7 @@ And directories are created for each configurable item of
> the display pipeline::
> tree /config/vkms/my-vkms
> ├── crtcs
> ├── enabled
> + ├── encoders
> └── planes
>
> To add items to the display pipeline, create one or more directories under
> the
> @@ -97,6 +98,10 @@ CRTCs have 1 configurable attribute:
>
> - writeback: Enable or disable writeback connector support
>
> +Next, create one or more encoders::
> +
> + sudo mkdir /config/vkms/my-vkms/encoders/encoder0
> +
> 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
> @@ -118,6 +123,7 @@ And removing the top level directory and its
> subdirectories::
> sudo rm /config/vkms/my-vkms/planes/*/possible_crtcs/*
> 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
>
> Testing With IGT
> diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c
> b/drivers/gpu/drm/vkms/vkms_configfs.c
> index 7d5ebdd45d53..d7efa50a3fba 100644
> --- a/drivers/gpu/drm/vkms/vkms_configfs.c
> +++ b/drivers/gpu/drm/vkms/vkms_configfs.c
> @@ -17,6 +17,7 @@ static bool is_configfs_registered;
> * Initialized when a new directory is created under "/config/vkms/"
> * @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"
> * @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
> @@ -26,6 +27,7 @@ struct vkms_configfs_device {
> struct config_group group;
> struct config_group planes_group;
> struct config_group crtcs_group;
> + struct config_group encoders_group;
>
> struct mutex lock;
> struct vkms_config *config;
> @@ -62,6 +64,20 @@ struct vkms_configfs_crtc {
> struct vkms_config_crtc *config;
> };
>
> +/**
> + * struct vkms_configfs_encoder - Configfs representation of a encoder
> + *
> + * @group: Top level configuration group that represents a encoder.
> + * Initialized when a new directory is created under "/config/vkms/encoders"
> + * @dev: The vkms_configfs_device this encoder belongs to
> + * @config: Configuration of the VKMS encoder
> + */
> +struct vkms_configfs_encoder {
> + struct config_group group;
> + struct vkms_configfs_device *dev;
> + struct vkms_config_encoder *config;
> +};
> +
> #define device_item_to_vkms_configfs_device(item) \
> container_of(to_config_group((item)), struct vkms_configfs_device, \
> group)
> @@ -79,6 +95,10 @@ struct vkms_configfs_crtc {
> #define crtc_item_to_vkms_configfs_crtc(item) \
> container_of(to_config_group((item)), struct vkms_configfs_crtc, group)
>
> +#define encoder_item_to_vkms_configfs_encoder(item) \
> + container_of(to_config_group((item)), struct vkms_configfs_encoder, \
> + group)
> +
> static ssize_t crtc_writeback_show(struct config_item *item, char *page)
> {
> struct vkms_configfs_crtc *crtc;
> @@ -382,6 +402,81 @@ static const struct config_item_type plane_group_type = {
> .ct_owner = THIS_MODULE,
> };
>
> +static void encoder_release(struct config_item *item)
> +{
> + struct vkms_configfs_encoder *encoder;
> + struct mutex *lock;
> +
> + encoder = encoder_item_to_vkms_configfs_encoder(item);
> + lock = &encoder->dev->lock;
> +
> + mutex_lock(lock);
> + vkms_config_destroy_encoder(encoder->dev->config, encoder->config);
> + kfree(encoder);
> + mutex_unlock(lock);
> +}
> +
> +static struct configfs_item_operations encoder_item_operations = {
> + .release = &encoder_release,
> +};
> +
> +static const struct config_item_type encoder_item_type = {
> + .ct_item_ops = &encoder_item_operations,
> + .ct_owner = THIS_MODULE,
> +};
> +
> +static struct config_group *make_encoder_group(struct config_group *group,
> + const char *name)
> +{
> + struct vkms_configfs_device *dev;
> + struct vkms_configfs_encoder *encoder;
> + int ret;
> +
> + dev = child_group_to_vkms_configfs_device(group);
> +
> + mutex_lock(&dev->lock);
> +
> + if (dev->enabled) {
> + ret = -EINVAL;
-EPERM/-EBUSY?
> + goto err_unlock;
> + }
> +
> + encoder = kzalloc(sizeof(*encoder), GFP_KERNEL);
> + if (!encoder) {
> + ret = -ENOMEM;
> + goto err_unlock;
> + }
> +
> + encoder->dev = dev;
> +
> + encoder->config = vkms_config_create_encoder(dev->config);
> + if (IS_ERR(encoder->config)) {
> + ret = PTR_ERR(encoder->config);
> + goto err_free;
> + }
> +
> + config_group_init_type_name(&encoder->group, name, &encoder_item_type);
> +
> + mutex_unlock(&dev->lock);
> +
> + return &encoder->group;
> +
> +err_free:
> + kfree(encoder);
> +err_unlock:
> + mutex_unlock(&dev->lock);
> + return ERR_PTR(ret);
> +}
> +
> +static struct configfs_group_operations encoders_group_operations = {
> + .make_group = &make_encoder_group,
> +};
> +
> +static const struct config_item_type encoder_group_type = {
> + .ct_group_ops = &encoders_group_operations,
> + .ct_owner = THIS_MODULE,
> +};
> +
> static ssize_t device_enabled_show(struct config_item *item, char *page)
> {
> struct vkms_configfs_device *dev;
> @@ -495,6 +590,10 @@ static struct config_group *make_device_group(struct
> config_group *group,
> &crtc_group_type);
> configfs_add_default_group(&dev->crtcs_group, &dev->group);
>
> + config_group_init_type_name(&dev->encoders_group, "encoders",
> + &encoder_group_type);
> + configfs_add_default_group(&dev->encoders_group, &dev->group);
> +
> return &dev->group;
> }
>
> --
> 2.48.1
>
