From 751465913f045a1120188ec91ed46d90ea5fd539 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 28 Jan 2020 14:55:03 +0100 Subject: drm/bridge: Add a drm_bridge_state object 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. v10: * Add changelog to the commit message v9: * Clarify the fact that the bridge->atomic_reset() and {connector,plane,crtc,...}->reset() semantics are different * Move the drm_atomic_private_obj_init() call back to drm_bridge_attach() * Check the presence of ->atomic_duplicate_state instead of ->atomic_reset in drm_atomic_add_encoder_bridges() * Fix copy&paste errors in the atomic bridge state helpers doc * Add A-b/R-b tags v8: * Move bridge state helpers out of the CONFIG_DEBUGFS section v7: * Move helpers, struct-defs, ... to atomic helper files to avoid the drm -> drm_kms_helper -> drm circular dep * Stop providing default implementation for atomic state reset, duplicate and destroy hooks (has to do with the helper/core split) * Drop all R-b/T-b as helpers have now be moved to other places v6: * Made helpers private, removed doc and moved them to satisfy dependencies * Renamed helpers to _default_ v5: * Re-introduced the helpers from v4 v4: * Fix the doc * Kill default helpers (inlined) * Fix drm_atomic_get_bridge_state() to check for an ERR_PTR() * Add Neil's R-b v3: * No changes 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 Signed-off-by: Boris Brezillon Signed-off-by: Neil Armstrong Reviewed-by: Neil Armstrong Acked-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-2-boris.brezillon@collabora.com --- drivers/gpu/drm/drm_atomic_state_helper.c | 103 ++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) (limited to 'drivers/gpu/drm/drm_atomic_state_helper.c') diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c index 7cf3cf936547..33141d2cdad4 100644 --- a/drivers/gpu/drm/drm_atomic_state_helper.c +++ b/drivers/gpu/drm/drm_atomic_state_helper.c @@ -26,6 +26,7 @@ #include #include +#include #include #include #include @@ -551,3 +552,105 @@ void __drm_atomic_helper_private_obj_duplicate_state(struct drm_private_obj *obj memcpy(state, obj->state, sizeof(*state)); } EXPORT_SYMBOL(__drm_atomic_helper_private_obj_duplicate_state); + +/** + * __drm_atomic_helper_bridge_duplicate_state() - Copy atomic bridge state + * @bridge: bridge object + * @state: atomic bridge state + * + * Copies atomic state from a bridge's current state and resets inferred values. + * This is useful for drivers that subclass the bridge state. + */ +void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge, + struct drm_bridge_state *state) +{ + __drm_atomic_helper_private_obj_duplicate_state(&bridge->base, + &state->base); + state->bridge = bridge; +} +EXPORT_SYMBOL(__drm_atomic_helper_bridge_duplicate_state); + +/** + * drm_atomic_helper_bridge_duplicate_state() - Duplicate a bridge state object + * @bridge: bridge object + * + * Allocates a new bridge state and initializes it with the current bridge + * state values. This helper is meant to be used as a bridge + * &drm_bridge_funcs.atomic_duplicate_state hook for bridges that don't + * subclass the bridge state. + */ +struct drm_bridge_state * +drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge) +{ + struct drm_bridge_state *new; + + if (WARN_ON(!bridge->base.state)) + return NULL; + + new = kzalloc(sizeof(*new), GFP_KERNEL); + if (new) + __drm_atomic_helper_bridge_duplicate_state(bridge, new); + + return new; +} +EXPORT_SYMBOL(drm_atomic_helper_bridge_duplicate_state); + +/** + * drm_atomic_helper_bridge_destroy_state() - Destroy a bridge state object + * @bridge: the bridge this state refers to + * @state: bridge state to destroy + * + * Destroys a bridge state previously created by + * &drm_atomic_helper_bridge_reset() or + * &drm_atomic_helper_bridge_duplicate_state(). This helper is meant to be + * used as a bridge &drm_bridge_funcs.atomic_destroy_state hook for bridges + * that don't subclass the bridge state. + */ +void drm_atomic_helper_bridge_destroy_state(struct drm_bridge *bridge, + struct drm_bridge_state *state) +{ + kfree(state); +} +EXPORT_SYMBOL(drm_atomic_helper_bridge_destroy_state); + +/** + * __drm_atomic_helper_bridge_reset() - Initialize a bridge state to its + * default + * @bridge: the bridge this state refers to + * @state: bridge state to initialize + * + * Initializes the bridge state to default values. This is meant to be called + * by the bridge &drm_bridge_funcs.atomic_reset hook for bridges that subclass + * the bridge state. + */ +void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge, + struct drm_bridge_state *state) +{ + memset(state, 0, sizeof(*state)); + state->bridge = bridge; +} +EXPORT_SYMBOL(__drm_atomic_helper_bridge_reset); + +/** + * drm_atomic_helper_bridge_reset() - Allocate and initialize a bridge state + * to its default + * @bridge: the bridge this state refers to + * @state: bridge state to initialize + * + * Allocates the bridge state and initializes it to default values. This helper + * is meant to be used as a bridge &drm_bridge_funcs.atomic_reset hook for + * bridges that don't subclass the bridge state. + */ +struct drm_bridge_state * +drm_atomic_helper_bridge_reset(struct drm_bridge *bridge) +{ + struct drm_bridge_state *bridge_state; + + bridge_state = kzalloc(sizeof(*bridge_state), GFP_KERNEL); + if (!bridge_state) + return ERR_PTR(-ENOMEM); + + __drm_atomic_helper_bridge_reset(bridge, bridge_state); + return bridge_state; +} +EXPORT_SYMBOL(drm_atomic_helper_bridge_reset); -- cgit v1.2.3