On 23/10/2019 17:45, Boris Brezillon wrote:
> One of the last remaining objects to not have its atomic state.
>
> This is being motivated by our attempt to support runtime bus-format
> negotiation between elements of the bridge chain.
> This patch just paves the road for such a feature by adding a new
> drm_bridge_state object inheriting from drm_private_obj so we can
> re-use some of the existing state initialization/tracking logic.
>
> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
> ---
> Changes in v3:
> * None
>
> Changes in v2:
> * Use drm_for_each_bridge_in_chain()
> * Rename helpers to be more consistent with the rest of the DRM API
> * Improve/fix the doc
> ---
> drivers/gpu/drm/drm_atomic.c | 39 +++++++
> drivers/gpu/drm/drm_atomic_helper.c | 20 ++++
> drivers/gpu/drm/drm_bridge.c | 168 +++++++++++++++++++++++++++-
> include/drm/drm_atomic.h | 3 +
> include/drm/drm_bridge.h | 118 +++++++++++++++++++
> 5 files changed, 343 insertions(+), 5 deletions(-)
>
[...]
> --- a/include/drm/drm_atomic.h
> +++ b/include/drm/drm_atomic.h
> @@ -660,6 +660,9 @@ __drm_atomic_get_current_plane_state(struct drm_atomic_state *state,
> return plane->state;
> }
>
> +int __must_check
> +drm_atomic_add_encoder_bridges(struct drm_atomic_state *state,
> + struct drm_encoder *encoder);
> int __must_check
> drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
> struct drm_crtc *crtc);
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index 238e84ab63a3..a608c47d1de5 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -25,6 +25,7 @@
>
> #include <linux/list.h>
> #include <linux/ctype.h>
> +#include <drm/drm_atomic.h>
> #include <drm/drm_encoder.h>
> #include <drm/drm_mode_object.h>
> #include <drm/drm_modes.h>
> @@ -33,6 +34,23 @@ struct drm_bridge;
> struct drm_bridge_timings;
> struct drm_panel;
>
> +/**
> + * struct drm_bridge_state - Atomic bridge state object
> + * @base: inherit from &drm_private_state
> + * @bridge: the bridge this state refers to
> + */
> +struct drm_bridge_state {
> + struct drm_private_state base;
> +
> + struct drm_bridge *bridge;
> +};
> +
> +static inline struct drm_bridge_state *
> +drm_priv_to_bridge_state(struct drm_private_state *priv)
> +{
> + return container_of(priv, struct drm_bridge_state, base);
> +}
> +
> /**
> * struct drm_bridge_funcs - drm_bridge control functions
> */
> @@ -338,6 +356,48 @@ struct drm_bridge_funcs {
> */
> void (*atomic_post_disable)(struct drm_bridge *bridge,
> struct drm_atomic_state *state);
> +
> + /**
> + * @atomic_duplicate_state:
> + *
> + * Duplicate the current bridge state object (which is guaranteed to be
> + * non-NULL).
> + *
> + * The atomic_duplicate_state() is optional, the core falls back on
> + * &drm_atomic_helper_bridge_duplicate_state() when not implemented.
> + *
> + * RETURNS:
> + * A valid drm_bridge_state object or NULL if the allocation fails.
> + */
> + struct drm_bridge_state *(*atomic_duplicate_state)(struct drm_bridge *bridge);
> +
> + /**
> + * @atomic_destroy_state:
> + *
> + * Destroy a bridge state object previously allocated by
> + * &drm_bridge_funcs.atomic_duplicate_state().
> + *
> + * The atomic_destroy_state hook is optional, the coref falls back on
> + * &drm_atomic_helper_bridge_destroy_state() when not implemented.
> + */
> + void (*atomic_destroy_state)(struct drm_bridge *bridge,
> + struct drm_bridge_state *state);
> +
> + /**
> + * @atomic_reset:
> + *
> + * Reset the bridge to a predefined state (or retrieve its current
> + * state) and return a &drm_bridge_state object matching this state.
> + * This function is called at attach time.
> + *
> + * The atomic_reset hook is optional, the core falls back on
> + * &drm_atomic_helper_bridge_reset() when not implemented.
> + *
> + * RETURNS:
> + * A valid drm_bridge_state object in case of success, an ERR_PTR()
> + * giving the reaon of the failure otherwise.
> + */
> + struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge);
> };
>
> /**
> @@ -380,6 +440,8 @@ struct drm_bridge_timings {
> * struct drm_bridge - central DRM bridge control structure
> */
> struct drm_bridge {
> + /** @base: inherit from &drm_private_object */
> + struct drm_private_obj base;
> /** @dev: DRM device this bridge belongs to */
> struct drm_device *dev;
> /** @encoder: encoder to which this bridge is connected */
> @@ -404,6 +466,12 @@ struct drm_bridge {
> void *driver_private;
> };
>
> +static inline struct drm_bridge *
> +drm_priv_to_bridge(struct drm_private_obj *priv)
> +{
> + return container_of(priv, struct drm_bridge, base);
> +}
> +
> void drm_bridge_add(struct drm_bridge *bridge);
> void drm_bridge_remove(struct drm_bridge *bridge);
> struct drm_bridge *of_drm_find_bridge(struct device_node *np);
> @@ -475,6 +543,56 @@ void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
> void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge,
> struct drm_atomic_state *state);
>
> +void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge,
> + struct drm_bridge_state *state);
> +struct drm_bridge_state *
> +drm_atomic_helper_bridge_reset(struct drm_bridge *bridge);
> +void drm_atomic_helper_bridge_destroy_state(struct drm_bridge *bridge,
> + struct drm_bridge_state *state);
> +void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge,
> + struct drm_bridge_state *new);
> +struct drm_bridge_state *
> +drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge);
> +
> +static inline struct drm_bridge_state *
> +drm_atomic_get_bridge_state(struct drm_atomic_state *state,
> + struct drm_bridge *bridge)
> +{
> + struct drm_private_state *obj_state;
> +
> + obj_state = drm_atomic_get_private_obj_state(state, &bridge->base);
> + if (!obj_state)
> + return NULL;
drm_atomic_get_private_obj_state will return an error object on error, so should be:
if (IS_ERR(obj_state))
return ERR_CAST(obj_state);
> +
> + return drm_priv_to_bridge_state(obj_state);
> +}
> +
> +static inline struct drm_bridge_state *
> +drm_atomic_get_old_bridge_state(struct drm_atomic_state *state,
> + struct drm_bridge *bridge)
> +{
> + struct drm_private_state *obj_state;
> +
> + obj_state = drm_atomic_get_old_private_obj_state(state, &bridge->base);
> + if (!obj_state)
> + return NULL;
> +
> + return drm_priv_to_bridge_state(obj_state);
> +}
> +
> +static inline struct drm_bridge_state *
> +drm_atomic_get_new_bridge_state(struct drm_atomic_state *state,
> + struct drm_bridge *bridge)
> +{
> + struct drm_private_state *obj_state;
> +
> + obj_state = drm_atomic_get_new_private_obj_state(state, &bridge->base);
> + if (!obj_state)
> + return NULL;
> +
> + return drm_priv_to_bridge_state(obj_state);
> +}
> +
> #ifdef CONFIG_DRM_PANEL_BRIDGE
> struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel);
> struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
>
With this fixed, you can keep my Reviewed-by
Neil
