On Wednesday, July 19th, 2023 at 03:42, Zack Rusin <zack@xxxxxxx> wrote:
> From: Zack Rusin <zackr@xxxxxxxxxx>
>
> Atomic modesetting code lacked support for specifying mouse cursor
> hotspots. The legacy kms DRM_IOCTL_MODE_CURSOR2 had support for setting
> the hotspot but the functionality was not implemented in the new atomic
> paths.
>
> Due to the lack of hotspots in the atomic paths userspace compositors
> completely disable atomic modesetting for drivers that require it (i.e.
> all paravirtualized drivers).
>
> This change adds hotspot properties to the atomic codepaths throughtout
> the DRM core and will allow enabling atomic modesetting for virtualized
> drivers in the userspace.
>
> Signed-off-by: Zack Rusin <zackr@xxxxxxxxxx>
> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
> Cc: Maxime Ripard <mripard@xxxxxxxxxx>
> Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
> Cc: David Airlie <airlied@xxxxxxxx>
> Cc: Daniel Vetter <daniel@xxxxxxxx>
> Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_atomic_state_helper.c | 14 +++++++
> drivers/gpu/drm/drm_atomic_uapi.c | 20 +++++++++
> drivers/gpu/drm/drm_plane.c | 50 +++++++++++++++++++++++
> include/drm/drm_plane.h | 14 +++++++
> 4 files changed, 98 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
> index 784e63d70a42..54975de44a0e 100644
> --- a/drivers/gpu/drm/drm_atomic_state_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_state_helper.c
> @@ -275,6 +275,20 @@ void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state,
> plane_state->normalized_zpos = val;
> }
> }
> +
> + if (plane->hotspot_x_property) {
> + if (!drm_object_property_get_default_value(&plane->base,
> + plane->hotspot_x_property,
> + &val))
> + plane_state->hotspot_x = val;
> + }
> +
> + if (plane->hotspot_y_property) {
> + if (!drm_object_property_get_default_value(&plane->base,
> + plane->hotspot_y_property,
> + &val))
> + plane_state->hotspot_y = val;
> + }
> }
> EXPORT_SYMBOL(__drm_atomic_helper_plane_state_reset);
>
> diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> index 98d3b10c08ae..07a7b3f18df2 100644
> --- a/drivers/gpu/drm/drm_atomic_uapi.c
> +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> @@ -593,6 +593,22 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
> } else if (plane->funcs->atomic_set_property) {
> return plane->funcs->atomic_set_property(plane, state,
> property, val);
> + } else if (property == plane->hotspot_x_property) {
> + if (plane->type != DRM_PLANE_TYPE_CURSOR) {
> + drm_dbg_atomic(plane->dev,
> + "[PLANE:%d:%s] is not a cursor plane: 0x%llx\n",
> + plane->base.id, plane->name, val);
> + return -EINVAL;
> + }
Hm, it sounds a bit weird to catch this case here. Wouldn't it be a driver bug
to attach the hotspot props to a plane which isn't a cursor? Wouldn't it make
more sense to WARN in drm_plane_create_hotspot_properties() if a driver
attempts to do so?
> + state->hotspot_x = val;
> + } else if (property == plane->hotspot_y_property) {
> + if (plane->type != DRM_PLANE_TYPE_CURSOR) {
> + drm_dbg_atomic(plane->dev,
> + "[PLANE:%d:%s] is not a cursor plane: 0x%llx\n",
> + plane->base.id, plane->name, val);
> + return -EINVAL;
> + }
> + state->hotspot_y = val;
> } else {
> drm_dbg_atomic(plane->dev,
> "[PLANE:%d:%s] unknown property [PROP:%d:%s]\n",
> @@ -653,6 +669,10 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
> *val = state->scaling_filter;
> } else if (plane->funcs->atomic_get_property) {
> return plane->funcs->atomic_get_property(plane, state, property, val);
> + } else if (property == plane->hotspot_x_property) {
> + *val = state->hotspot_x;
> + } else if (property == plane->hotspot_y_property) {
> + *val = state->hotspot_y;
> } else {
> drm_dbg_atomic(dev,
> "[PLANE:%d:%s] unknown property [PROP:%d:%s]\n",
> diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
> index c6bbb0c209f4..eaca367bdc7e 100644
> --- a/drivers/gpu/drm/drm_plane.c
> +++ b/drivers/gpu/drm/drm_plane.c
> @@ -230,6 +230,47 @@ static int create_in_format_blob(struct drm_device *dev, struct drm_plane *plane
> return 0;
> }
>
> +/**
> + * drm_plane_create_hotspot_properties - creates the mouse hotspot
> + * properties and attaches them to the given cursor plane
> + *
> + * @plane: drm cursor plane
> + *
> + * This function enables the mouse hotspot property on a given
> + * cursor plane.
> + *
> + * RETURNS:
> + * Zero for success or -errno
> + */
> +static int drm_plane_create_hotspot_properties(struct drm_plane *plane)
> +{
> + struct drm_property *prop_x;
> + struct drm_property *prop_y;
> +
> + drm_WARN_ON(plane->dev,
> + !drm_core_check_feature(plane->dev,
> + DRIVER_CURSOR_HOTSPOT));
> +
> + prop_x = drm_property_create_signed_range(plane->dev, 0, "HOTSPOT_X",
> + INT_MIN, INT_MAX);
This is an atomic-only property, the DRM_MODE_PROP_ATOMIC flag should be passed.
> + if (IS_ERR(prop_x))
> + return PTR_ERR(prop_x);
> +
> + prop_y = drm_property_create_signed_range(plane->dev, 0, "HOTSPOT_Y",
> + INT_MIN, INT_MAX);
> + if (IS_ERR(prop_y)) {
> + drm_property_destroy(plane->dev, prop_x);
> + return PTR_ERR(prop_y);
> + }
> +
> + drm_object_attach_property(&plane->base, prop_x, 0);
> + drm_object_attach_property(&plane->base, prop_y, 0);
> + plane->hotspot_x_property = prop_x;
> + plane->hotspot_y_property = prop_y;
> +
> + return 0;
> +}
