On Tue, Oct 11, 2016 at 03:54:04PM +0100, Brian Starkey wrote:
> So that userspace can determine what pixel formats are supported for a
> writeback connector's framebuffer, add a pixel format list to writeback
> connectors. This is in the form of an immutable blob containing an array
> of formats, and an immutable uint holding the array size.
>
> Signed-off-by: Brian Starkey
I think we should have a dedicated writeback property registration
function, e.g. drm_writeback_connector_init(). That would then take the
pixel format list and everything else and make sure it's set up correctly.
For safety we might want to put a WARN_ON(type == WRITEBACK) into
drm_connector_init, to make sure no one botches this up.
Maybe even put all that into a new drm_writeback.c file, that then also
gives you a nice place to group all the documentation (including the DOC:
overview comment).
> ---
> drivers/gpu/drm/drm_connector.c | 73
> ++-
> include/drm/drm_connector.h | 12 +++
> include/drm/drm_crtc.h | 12 +++
> 3 files changed, 96 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index fb83870..2f1f61d 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -249,9 +249,14 @@ int drm_connector_init(struct drm_device *dev,
> drm_object_attach_property(&connector->base,
> config->prop_crtc_id, 0);
> }
>
> - if (connector_type == DRM_MODE_CONNECTOR_WRITEBACK)
> + if (connector_type == DRM_MODE_CONNECTOR_WRITEBACK) {
> drm_object_attach_property(&connector->base,
> config->prop_fb_id, 0);
> + drm_object_attach_property(&connector->base,
> +config->pixel_formats_property, 0);
> + drm_object_attach_property(&connector->base,
> +config->pixel_formats_size_property,
> 0);
> + }
>
> connector->debugfs_entry = NULL;
> out_put_type_id:
> @@ -851,6 +856,45 @@ int drm_mode_create_suggested_offset_properties(struct
> drm_device *dev)
> EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);
>
> /**
> + * drm_mode_create_writeback_connector_properties - create writeback
> connector properties
> + * @dev: DRM device
> + *
> + * Create the properties specific to writeback connectors. These will be
> attached
> + * to writeback connectors by drm_connector_init. Drivers can set these
> + * properties using drm_mode_connector_set_writeback_formats().
> + *
> + * "PIXEL_FORMATS":
> + * Immutable blob property to store the supported pixel formats table. The
> + * data is an array of u32 DRM_FORMAT_* fourcc values.
> + * Userspace can use this blob to find out what pixel formats are supported
> + * by the connector's writeback engine.
> + *
> + * "PIXEL_FORMATS_SIZE":
> + * Immutable unsigned range property storing the number of entries in
> the
> + * PIXEL_FORMATS array.
> + */
> +int drm_mode_create_writeback_connector_properties(struct drm_device *dev)
> +{
> + if (dev->mode_config.pixel_formats_property &&
> + dev->mode_config.pixel_formats_size_property)
> + return 0;
> +
> + dev->mode_config.pixel_formats_property =
> + drm_property_create(dev, DRM_MODE_PROP_BLOB |
> DRM_MODE_PROP_IMMUTABLE,
> + "PIXEL_FORMATS", 0);
> +
> + dev->mode_config.pixel_formats_size_property =
> + drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE,
> + "PIXEL_FORMATS_SIZE", 0, UINT_MAX);
> +
> + if (dev->mode_config.pixel_formats_property == NULL ||
> + dev->mode_config.pixel_formats_size_property == NULL)
> + return -ENOMEM;
> + return 0;
> +}
> +EXPORT_SYMBOL(drm_mode_create_writeback_connector_properties);
> +
> +/**
> * drm_mode_connector_set_path_property - set tile property on connector
> * @connector: connector to set property on.
> * @path: path to use for property; must not be NULL.
> @@ -957,6 +1001,33 @@ int drm_mode_connector_update_edid_property(struct
> drm_connector *connector,
> }
> EXPORT_SYMBOL(drm_mode_connector_update_edid_property);
>
> +int drm_mode_connector_set_writeback_formats(struct drm_connector *connector,
> + u32 *formats,
> + unsigned int n_formats)
> +{
> + struct drm_device *dev = connector->dev;
> + size_t size = n_formats * sizeof(*formats);
> + int ret;
> +
> + if (connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
> + return -EINVAL;
> +
> + ret = drm_property_replace_global_blob(dev,
> +
> &connector->pixel_formats_blob_ptr,
> +size,
> +forma
