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@collabora.com Reviewed-by: Neil Armstrong narmstrong@baylibre.com --- Changes in 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
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 | 118 ++++++++++++++++++++++++++-- include/drm/drm_atomic.h | 3 + include/drm/drm_bridge.h | 116 +++++++++++++++++++++++++++ 5 files changed, 290 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 14aeaf736321..02f8034f5240 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -30,6 +30,7 @@
#include <drm/drm_atomic.h> #include <drm/drm_atomic_uapi.h> +#include <drm/drm_bridge.h> #include <drm/drm_debugfs.h> #include <drm/drm_device.h> #include <drm/drm_drv.h> @@ -1015,6 +1016,44 @@ static void drm_atomic_connector_print_state(struct drm_printer *p, connector->funcs->atomic_print_state(p, state); }
+/** + * drm_atomic_add_encoder_bridges - add bridges attached to an encoder + * @state: atomic state + * @encoder: DRM encoder + * + * This function adds all bridges attached to @encoder. This is needed to add + * bridge states to @state and make them available when + * &bridge_funcs.atomic_{check,pre_enable,enable,disable_post_disable}() are + * called + * + * Returns: + * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK + * then the w/w mutex code has detected a deadlock and the entire atomic + * sequence must be restarted. All other errors are fatal. + */ +int +drm_atomic_add_encoder_bridges(struct drm_atomic_state *state, + struct drm_encoder *encoder) +{ + struct drm_bridge_state *bridge_state; + struct drm_bridge *bridge; + + if (!encoder) + return 0; + + DRM_DEBUG_ATOMIC("Adding all bridges for [encoder:%d:%s] to %p\n", + encoder->base.id, encoder->name, state); + + drm_for_each_bridge_in_chain(encoder, bridge) { + bridge_state = drm_atomic_get_bridge_state(state, bridge); + if (IS_ERR(bridge_state)) + return PTR_ERR(bridge_state); + } + + return 0; +} +EXPORT_SYMBOL(drm_atomic_add_encoder_bridges); + /** * drm_atomic_add_affected_connectors - add connectors for crtc * @state: atomic state diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 29c3115bf9e2..e2f7f336a2d2 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -730,6 +730,26 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, return ret; }
+ /* + * Iterate over all connectors again, and add all affected bridges to + * the state. + */ + for_each_oldnew_connector_in_state(state, connector, + old_connector_state, + new_connector_state, i) { + struct drm_encoder *encoder; + + encoder = old_connector_state->best_encoder; + ret = drm_atomic_add_encoder_bridges(state, encoder); + if (ret) + return ret; + + encoder = new_connector_state->best_encoder; + ret = drm_atomic_add_encoder_bridges(state, encoder); + if (ret) + return ret; + } + ret = mode_valid(state); if (ret) return ret; diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index b6517b4fa3d1..bf5a2243a115 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -25,6 +25,7 @@ #include <linux/module.h> #include <linux/mutex.h>
+#include <drm/drm_atomic_state_helper.h> #include <drm/drm_bridge.h> #include <drm/drm_encoder.h>
@@ -89,6 +90,48 @@ void drm_bridge_remove(struct drm_bridge *bridge) } EXPORT_SYMBOL(drm_bridge_remove);
+static struct drm_private_state * +drm_bridge_atomic_duplicate_priv_state(struct drm_private_obj *obj) +{ + struct drm_bridge *bridge = drm_priv_to_bridge(obj); + struct drm_bridge_state *state; + + if (bridge->funcs->atomic_duplicate_state) { + state = bridge->funcs->atomic_duplicate_state(bridge); + + return state ? &state->base : NULL; + } + + if (WARN_ON(!bridge->base.state)) + return NULL; + + state = kzalloc(sizeof(*state), GFP_KERNEL); + if (!state) + return NULL; + + __drm_atomic_helper_bridge_duplicate_state(bridge, state); + + return &state->base; +} + +static void +drm_bridge_atomic_destroy_priv_state(struct drm_private_obj *obj, + struct drm_private_state *s) +{ + struct drm_bridge_state *state = drm_priv_to_bridge_state(s); + struct drm_bridge *bridge = drm_priv_to_bridge(obj); + + if (bridge->funcs->atomic_destroy_state) + bridge->funcs->atomic_destroy_state(bridge, state); + else + kfree(state); +} + +static const struct drm_private_state_funcs drm_bridge_priv_state_funcs = { + .atomic_duplicate_state = drm_bridge_atomic_duplicate_priv_state, + .atomic_destroy_state = drm_bridge_atomic_destroy_priv_state, +}; + /** * drm_bridge_attach - attach the bridge to an encoder's chain * @@ -114,6 +157,7 @@ EXPORT_SYMBOL(drm_bridge_remove); int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, struct drm_bridge *previous) { + struct drm_bridge_state *state; int ret;
if (!encoder || !bridge) @@ -135,15 +179,40 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
if (bridge->funcs->attach) { ret = bridge->funcs->attach(bridge); - if (ret < 0) { - list_del(&bridge->chain_node); - bridge->dev = NULL; - bridge->encoder = NULL; - return ret; - } + if (ret < 0) + goto err_reset_bridge; }
+ if (bridge->funcs->atomic_reset) { + state = bridge->funcs->atomic_reset(bridge); + } else { + state = kzalloc(sizeof(*state), GFP_KERNEL); + if (state) + __drm_atomic_helper_bridge_reset(bridge, state); + else + state = ERR_PTR(-ENOMEM); + } + + if (IS_ERR(state)) { + ret = PTR_ERR(state); + goto err_detach_bridge; + } + + drm_atomic_private_obj_init(bridge->dev, &bridge->base, + &state->base, + &drm_bridge_priv_state_funcs); + return 0; + +err_detach_bridge: + if (bridge->funcs->detach) + bridge->funcs->detach(bridge); + +err_reset_bridge: + bridge->dev = NULL; + bridge->encoder = NULL; + list_del(&bridge->chain_node); + return ret; } EXPORT_SYMBOL(drm_bridge_attach);
@@ -155,6 +224,8 @@ void drm_bridge_detach(struct drm_bridge *bridge) if (WARN_ON(!bridge->dev)) return;
+ drm_atomic_private_obj_fini(&bridge->base); + if (bridge->funcs->detach) bridge->funcs->detach(bridge);
@@ -516,6 +587,41 @@ void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, } EXPORT_SYMBOL(drm_atomic_bridge_chain_enable);
+/** + * __drm_atomic_helper_bridge_reset() - Initialize a bridge state to its + * default + * @bridge: the bridge this state is refers to + * @state: bridge state to initialize + * + * Initialize the bridge state to default values. This is meant to be* called + * by the bridge &drm_plane_funcs.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_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); + #ifdef CONFIG_OF /** * of_drm_find_bridge - find the bridge corresponding to the device node in diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h index b6c73fd9f55a..e08582773d6c 100644 --- 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 d7d714023050..db5fc18d49bd 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -25,6 +25,8 @@
#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 +35,23 @@ 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 +357,49 @@ struct drm_bridge_funcs { */ void (*atomic_post_disable)(struct drm_bridge *bridge, struct drm_atomic_state *old_state); + + /** + * @atomic_duplicate_state: + * + * Duplicate the current bridge state object (which is guaranteed to be + * non-NULL). + * + * The atomic_duplicate_state() is optional. When not implemented the + * core allocates a drm_bridge_state object and calls + * &__drm_atomic_helper_bridge_duplicate_state() to initialize it. + * + * 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. When not implemented the + * core calls kfree() on the state. + */ + 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. When not implemented the core + * allocates a new state and calls &__drm_atomic_helper_bridge_reset(). + * + * RETURNS: + * A valid drm_bridge_state object in case of success, an ERR_PTR() + * giving the reason of the failure otherwise. + */ + struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge); };
/** @@ -380,6 +442,8 @@ 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 +468,12 @@ 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); @@ -491,6 +561,52 @@ 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_duplicate_state(struct drm_bridge *bridge, + struct drm_bridge_state *new); + +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 (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,