diff options
Diffstat (limited to 'include/drm/drm_bridge.h')
| -rw-r--r-- | include/drm/drm_bridge.h | 533 |
1 files changed, 492 insertions, 41 deletions
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index c0a2286a81e9..ea2aa5ebae34 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -23,14 +23,32 @@ #ifndef __DRM_BRIDGE_H__ #define __DRM_BRIDGE_H__ -#include <linux/list.h> #include <linux/ctype.h> +#include <linux/list.h> +#include <linux/mutex.h> + +#include <drm/drm_atomic.h> +#include <drm/drm_encoder.h> #include <drm/drm_mode_object.h> #include <drm/drm_modes.h> struct drm_bridge; struct drm_bridge_timings; +struct drm_connector; struct drm_panel; +struct edid; +struct i2c_adapter; + +/** + * enum drm_bridge_attach_flags - Flags for &drm_bridge_funcs.attach + */ +enum drm_bridge_attach_flags { + /** + * @DRM_BRIDGE_ATTACH_NO_CONNECTOR: When this flag is set the bridge + * shall not create a drm_connector. + */ + DRM_BRIDGE_ATTACH_NO_CONNECTOR = BIT(0), +}; /** * struct drm_bridge_funcs - drm_bridge control functions @@ -40,7 +58,8 @@ struct drm_bridge_funcs { * @attach: * * This callback is invoked whenever our bridge is being attached to a - * &drm_encoder. + * &drm_encoder. The flags argument tunes the behaviour of the attach + * operation (see DRM_BRIDGE_ATTACH_*). * * The @attach callback is optional. * @@ -48,7 +67,8 @@ struct drm_bridge_funcs { * * Zero on success, error code on failure. */ - int (*attach)(struct drm_bridge *bridge); + int (*attach)(struct drm_bridge *bridge, + enum drm_bridge_attach_flags flags); /** * @detach: @@ -108,7 +128,9 @@ struct drm_bridge_funcs { * this function passes all other callbacks must succeed for this * configuration. * - * The @mode_fixup callback is optional. + * The mode_fixup callback is optional. &drm_bridge_funcs.mode_fixup() + * is not called when &drm_bridge_funcs.atomic_check() is implemented, + * so only one of them should be provided. * * NOTE: * @@ -254,14 +276,15 @@ struct drm_bridge_funcs { * there is one) when this callback is called. * * Note that this function will only be invoked in the context of an - * atomic commit. It will not be invoked from &drm_bridge_pre_enable. It - * would be prudent to also provide an implementation of @pre_enable if - * you are expecting driver calls into &drm_bridge_pre_enable. + * atomic commit. It will not be invoked from + * &drm_bridge_chain_pre_enable. It would be prudent to also provide an + * implementation of @pre_enable if you are expecting driver calls into + * &drm_bridge_chain_pre_enable. * * The @atomic_pre_enable callback is optional. */ void (*atomic_pre_enable)(struct drm_bridge *bridge, - struct drm_atomic_state *state); + struct drm_bridge_state *old_bridge_state); /** * @atomic_enable: @@ -279,14 +302,14 @@ struct drm_bridge_funcs { * chain if there is one. * * Note that this function will only be invoked in the context of an - * atomic commit. It will not be invoked from &drm_bridge_enable. It - * would be prudent to also provide an implementation of @enable if - * you are expecting driver calls into &drm_bridge_enable. + * atomic commit. It will not be invoked from &drm_bridge_chain_enable. + * It would be prudent to also provide an implementation of @enable if + * you are expecting driver calls into &drm_bridge_chain_enable. * * The @atomic_enable callback is optional. */ void (*atomic_enable)(struct drm_bridge *bridge, - struct drm_atomic_state *state); + struct drm_bridge_state *old_bridge_state); /** * @atomic_disable: * @@ -301,14 +324,15 @@ struct drm_bridge_funcs { * signals) feeding it is still running when this callback is called. * * Note that this function will only be invoked in the context of an - * atomic commit. It will not be invoked from &drm_bridge_disable. It - * would be prudent to also provide an implementation of @disable if - * you are expecting driver calls into &drm_bridge_disable. + * atomic commit. It will not be invoked from + * &drm_bridge_chain_disable. It would be prudent to also provide an + * implementation of @disable if you are expecting driver calls into + * &drm_bridge_chain_disable. * * The @atomic_disable callback is optional. */ void (*atomic_disable)(struct drm_bridge *bridge, - struct drm_atomic_state *state); + struct drm_bridge_state *old_bridge_state); /** * @atomic_post_disable: @@ -325,15 +349,284 @@ struct drm_bridge_funcs { * called. * * Note that this function will only be invoked in the context of an - * atomic commit. It will not be invoked from &drm_bridge_post_disable. + * atomic commit. It will not be invoked from + * &drm_bridge_chain_post_disable. * It would be prudent to also provide an implementation of * @post_disable if you are expecting driver calls into - * &drm_bridge_post_disable. + * &drm_bridge_chain_post_disable. * * The @atomic_post_disable callback is optional. */ void (*atomic_post_disable)(struct drm_bridge *bridge, - struct drm_atomic_state *state); + struct drm_bridge_state *old_bridge_state); + + /** + * @atomic_duplicate_state: + * + * Duplicate the current bridge state object (which is guaranteed to be + * non-NULL). + * + * The atomic_duplicate_state hook is mandatory if the bridge + * implements any of the atomic hooks, and should be left unassigned + * otherwise. For bridges that don't subclass &drm_bridge_state, the + * drm_atomic_helper_bridge_duplicate_state() helper function shall be + * used to implement this hook. + * + * 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 mandatory if the bridge implements + * any of the atomic hooks, and should be left unassigned otherwise. + * For bridges that don't subclass &drm_bridge_state, the + * drm_atomic_helper_bridge_destroy_state() helper function shall be + * used to implement this hook. + */ + void (*atomic_destroy_state)(struct drm_bridge *bridge, + struct drm_bridge_state *state); + + /** + * @atomic_get_output_bus_fmts: + * + * Return the supported bus formats on the output end of a bridge. + * The returned array must be allocated with kmalloc() and will be + * freed by the caller. If the allocation fails, NULL should be + * returned. num_output_fmts must be set to the returned array size. + * Formats listed in the returned array should be listed in decreasing + * preference order (the core will try all formats until it finds one + * that works). + * + * This method is only called on the last element of the bridge chain + * as part of the bus format negotiation process that happens in + * &drm_atomic_bridge_chain_select_bus_fmts(). + * This method is optional. When not implemented, the core will + * fall back to &drm_connector.display_info.bus_formats[0] if + * &drm_connector.display_info.num_bus_formats > 0, + * or to MEDIA_BUS_FMT_FIXED otherwise. + */ + u32 *(*atomic_get_output_bus_fmts)(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + unsigned int *num_output_fmts); + + /** + * @atomic_get_input_bus_fmts: + * + * Return the supported bus formats on the input end of a bridge for + * a specific output bus format. + * + * The returned array must be allocated with kmalloc() and will be + * freed by the caller. If the allocation fails, NULL should be + * returned. num_output_fmts must be set to the returned array size. + * Formats listed in the returned array should be listed in decreasing + * preference order (the core will try all formats until it finds one + * that works). When the format is not supported NULL should be + * returned and num_output_fmts should be set to 0. + * + * This method is called on all elements of the bridge chain as part of + * the bus format negotiation process that happens in + * drm_atomic_bridge_chain_select_bus_fmts(). + * This method is optional. When not implemented, the core will bypass + * bus format negotiation on this element of the bridge without + * failing, and the previous element in the chain will be passed + * MEDIA_BUS_FMT_FIXED as its output bus format. + * + * Bridge drivers that need to support being linked to bridges that are + * not supporting bus format negotiation should handle the + * output_fmt == MEDIA_BUS_FMT_FIXED case appropriately, by selecting a + * sensible default value or extracting this information from somewhere + * else (FW property, &drm_display_mode, &drm_display_info, ...) + * + * Note: Even if input format selection on the first bridge has no + * impact on the negotiation process (bus format negotiation stops once + * we reach the first element of the chain), drivers are expected to + * return accurate input formats as the input format may be used to + * configure the CRTC output appropriately. + */ + u32 *(*atomic_get_input_bus_fmts)(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + u32 output_fmt, + unsigned int *num_input_fmts); + + /** + * @atomic_check: + * + * This method is responsible for checking bridge state correctness. + * It can also check the state of the surrounding components in chain + * to make sure the whole pipeline can work properly. + * + * &drm_bridge_funcs.atomic_check() hooks are called in reverse + * order (from the last to the first bridge). + * + * This method is optional. &drm_bridge_funcs.mode_fixup() is not + * called when &drm_bridge_funcs.atomic_check() is implemented, so only + * one of them should be provided. + * + * If drivers need to tweak &drm_bridge_state.input_bus_cfg.flags or + * &drm_bridge_state.output_bus_cfg.flags it should should happen in + * this function. By default the &drm_bridge_state.output_bus_cfg.flags + * field is set to the next bridge + * &drm_bridge_state.input_bus_cfg.flags value or + * &drm_connector.display_info.bus_flags if the bridge is the last + * element in the chain. + * + * RETURNS: + * zero if the check passed, a negative error code otherwise. + */ + int (*atomic_check)(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_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 mandatory if the bridge implements any of + * the atomic hooks, and should be left unassigned otherwise. For + * bridges that don't subclass &drm_bridge_state, the + * drm_atomic_helper_bridge_reset() helper function shall be used to + * implement this hook. + * + * Note that the atomic_reset() semantics is not exactly matching the + * reset() semantics found on other components (connector, plane, ...). + * + * 1. The reset operation happens when the bridge is attached, not when + * drm_mode_config_reset() is called + * 2. It's meant to be used exclusively on bridges that have been + * converted to the ATOMIC API + * + * 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); + + /** + * @detect: + * + * Check if anything is attached to the bridge output. + * + * This callback is optional, if not implemented the bridge will be + * considered as always having a component attached to its output. + * Bridges that implement this callback shall set the + * DRM_BRIDGE_OP_DETECT flag in their &drm_bridge->ops. + * + * RETURNS: + * + * drm_connector_status indicating the bridge output status. + */ + enum drm_connector_status (*detect)(struct drm_bridge *bridge); + + /** + * @get_modes: + * + * Fill all modes currently valid for the sink into the &drm_connector + * with drm_mode_probed_add(). + * + * The @get_modes callback is mostly intended to support non-probeable + * displays such as many fixed panels. Bridges that support reading + * EDID shall leave @get_modes unimplemented and implement the + * &drm_bridge_funcs->get_edid callback instead. + * + * This callback is optional. Bridges that implement it shall set the + * DRM_BRIDGE_OP_MODES flag in their &drm_bridge->ops. + * + * The connector parameter shall be used for the sole purpose of + * filling modes, and shall not be stored internally by bridge drivers + * for future usage. + * + * RETURNS: + * + * The number of modes added by calling drm_mode_probed_add(). + */ + int (*get_modes)(struct drm_bridge *bridge, + struct drm_connector *connector); + + /** + * @get_edid: + * + * Read and parse the EDID data of the connected display. + * + * The @get_edid callback is the preferred way of reporting mode + * information for a display connected to the bridge output. Bridges + * that support reading EDID shall implement this callback and leave + * the @get_modes callback unimplemented. + * + * The caller of this operation shall first verify the output + * connection status and refrain from reading EDID from a disconnected + * output. + * + * This callback is optional. Bridges that implement it shall set the + * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops. + * + * The connector parameter shall be used for the sole purpose of EDID + * retrieval and parsing, and shall not be stored internally by bridge + * drivers for future usage. + * + * RETURNS: + * + * An edid structure newly allocated with kmalloc() (or similar) on + * success, or NULL otherwise. The caller is responsible for freeing + * the returned edid structure with kfree(). + */ + struct edid *(*get_edid)(struct drm_bridge *bridge, + struct drm_connector *connector); + + /** + * @hpd_notify: + * + * Notify the bridge of hot plug detection. + * + * This callback is optional, it may be implemented by bridges that + * need to be notified of display connection or disconnection for + * internal reasons. One use case is to reset the internal state of CEC + * controllers for HDMI bridges. + */ + void (*hpd_notify)(struct drm_bridge *bridge, + enum drm_connector_status status); + + /** + * @hpd_enable: + * + * Enable hot plug detection. From now on the bridge shall call + * drm_bridge_hpd_notify() each time a change is detected in the output + * connection status, until hot plug detection gets disabled with + * @hpd_disable. + * + * This callback is optional and shall only be implemented by bridges + * that support hot-plug notification without polling. Bridges that + * implement it shall also implement the @hpd_disable callback and set + * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. + */ + void (*hpd_enable)(struct drm_bridge *bridge); + + /** + * @hpd_disable: + * + * Disable hot plug detection. Once this function returns the bridge + * shall not call drm_bridge_hpd_notify() when a change in the output + * connection status occurs. + * + * This callback is optional and shall only be implemented by bridges + * that support hot-plug notification without polling. Bridges that + * implement it shall also implement the @hpd_enable callback and set + * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. + */ + void (*hpd_disable)(struct drm_bridge *bridge); }; /** @@ -373,15 +666,50 @@ struct drm_bridge_timings { }; /** + * enum drm_bridge_ops - Bitmask of operations supported by the bridge + */ +enum drm_bridge_ops { + /** + * @DRM_BRIDGE_OP_DETECT: The bridge can detect displays connected to + * its output. Bridges that set this flag shall implement the + * &drm_bridge_funcs->detect callback. + */ + DRM_BRIDGE_OP_DETECT = BIT(0), + /** + * @DRM_BRIDGE_OP_EDID: The bridge can retrieve the EDID of the display + * connected to its output. Bridges that set this flag shall implement + * the &drm_bridge_funcs->get_edid callback. + */ + DRM_BRIDGE_OP_EDID = BIT(1), + /** + * @DRM_BRIDGE_OP_HPD: The bridge can detect hot-plug and hot-unplug + * without requiring polling. Bridges that set this flag shall + * implement the &drm_bridge_funcs->hpd_enable and + * &drm_bridge_funcs->hpd_disable callbacks if they support enabling + * and disabling hot-plug detection dynamically. + */ + DRM_BRIDGE_OP_HPD = BIT(2), + /** + * @DRM_BRIDGE_OP_MODES: The bridge can retrieve the modes supported + * by the display at its output. This does not include reading EDID + * which is separately covered by @DRM_BRIDGE_OP_EDID. Bridges that set + * this flag shall implement the &drm_bridge_funcs->get_modes callback. + */ + DRM_BRIDGE_OP_MODES = BIT(3), +}; + +/** * 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 */ struct drm_encoder *encoder; - /** @next: the next bridge in the encoder chain */ - struct drm_bridge *next; + /** @chain_node: used to form a bridge chain */ + struct list_head chain_node; #ifdef CONFIG_OF /** @of_node: device node pointer to the bridge */ struct device_node *of_node; @@ -398,35 +726,157 @@ struct drm_bridge { const struct drm_bridge_funcs *funcs; /** @driver_private: pointer to the bridge driver's internal context */ void *driver_private; + /** @ops: bitmask of operations supported by the bridge */ + enum drm_bridge_ops ops; + /** + * @type: Type of the connection at the bridge output + * (DRM_MODE_CONNECTOR_*). For bridges at the end of this chain this + * identifies the type of connected display. + */ + int type; + /** + * @interlace_allowed: Indicate that the bridge can handle interlaced + * modes. + */ + bool interlace_allowed; + /** + * @ddc: Associated I2C adapter for DDC access, if any. + */ + struct i2c_adapter *ddc; + /** private: */ + /** + * @hpd_mutex: Protects the @hpd_cb and @hpd_data fields. + */ + struct mutex hpd_mutex; + /** + * @hpd_cb: Hot plug detection callback, registered with + * drm_bridge_hpd_enable(). + */ + void (*hpd_cb)(void *data, enum drm_connector_status status); + /** + * @hpd_data: Private data passed to the Hot plug detection callback + * @hpd_cb. + */ + void *hpd_data; }; +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); int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, - struct drm_bridge *previous); + struct drm_bridge *previous, + enum drm_bridge_attach_flags flags); -bool drm_bridge_mode_fixup(struct drm_bridge *bridge, - const struct drm_display_mode *mode, - struct drm_display_mode *adjusted_mode); -enum drm_mode_status drm_bridge_mode_valid(struct drm_bridge *bridge, - const struct drm_display_mode *mode); -void drm_bridge_disable(struct drm_bridge *bridge); -void drm_bridge_post_disable(struct drm_bridge *bridge); -void drm_bridge_mode_set(struct drm_bridge *bridge, - const struct drm_display_mode *mode, - const struct drm_display_mode *adjusted_mode); -void drm_bridge_pre_enable(struct drm_bridge *bridge); -void drm_bridge_enable(struct drm_bridge *bridge); +/** + * drm_bridge_get_next_bridge() - Get the next bridge in the chain + * @bridge: bridge object + * + * RETURNS: + * the next bridge in the chain after @bridge, or NULL if @bridge is the last. + */ +static inline struct drm_bridge * +drm_bridge_get_next_bridge(struct drm_bridge *bridge) +{ + if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain)) + return NULL; -void drm_atomic_bridge_disable(struct drm_bridge *bridge, - struct drm_atomic_state *state); -void drm_atomic_bridge_post_disable(struct drm_bridge *bridge, + return list_next_entry(bridge, chain_node); +} + +/** + * drm_bridge_get_prev_bridge() - Get the previous bridge in the chain + * @bridge: bridge object + * + * RETURNS: + * the previous bridge in the chain, or NULL if @bridge is the first. + */ +static inline struct drm_bridge * +drm_bridge_get_prev_bridge(struct drm_bridge *bridge) +{ + if (list_is_first(&bridge->chain_node, &bridge->encoder->bridge_chain)) + return NULL; + + return list_prev_entry(bridge, chain_node); +} + +/** + * drm_bridge_chain_get_first_bridge() - Get the first bridge in the chain + * @encoder: encoder object + * + * RETURNS: + * the first bridge in the chain, or NULL if @encoder has no bridge attached + * to it. + */ +static inline struct drm_bridge * +drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder) +{ + return list_first_entry_or_null(&encoder->bridge_chain, + struct drm_bridge, chain_node); +} + +/** + * drm_for_each_bridge_in_chain() - Iterate over all bridges present in a chain + * @encoder: the encoder to iterate bridges on + * @bridge: a bridge pointer updated to point to the current bridge at each + * iteration + * + * Iterate over all bridges present in the bridge chain attached to @encoder. + */ +#define drm_for_each_bridge_in_chain(encoder, bridge) \ + list_for_each_entry(bridge, &(encoder)->bridge_chain, chain_node) + +bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode); +enum drm_mode_status +drm_bridge_chain_mode_valid(struct drm_bridge *bridge, + const struct drm_display_mode *mode); +void drm_bridge_chain_disable(struct drm_bridge *bridge); +void drm_bridge_chain_post_disable(struct drm_bridge *bridge); +void drm_bridge_chain_mode_set(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + const struct drm_display_mode *adjusted_mode); +void drm_bridge_chain_pre_enable(struct drm_bridge *bridge); +void drm_bridge_chain_enable(struct drm_bridge *bridge); + +int drm_atomic_bridge_chain_check(struct drm_bridge *bridge, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state); +void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge, + struct drm_atomic_state *state); +void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge, + struct drm_atomic_state *state); +void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge, + struct drm_atomic_state *state); +void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, struct drm_atomic_state *state); -void drm_atomic_bridge_pre_enable(struct drm_bridge *bridge, - struct drm_atomic_state *state); -void drm_atomic_bridge_enable(struct drm_bridge *bridge, - struct drm_atomic_state *state); + +u32 * +drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + u32 output_fmt, + unsigned int *num_input_fmts); + +enum drm_connector_status drm_bridge_detect(struct drm_bridge *bridge); +int drm_bridge_get_modes(struct drm_bridge *bridge, + struct drm_connector *connector); +struct edid *drm_bridge_get_edid(struct drm_bridge *bridge, + struct drm_connector *connector); +void drm_bridge_hpd_enable(struct drm_bridge *bridge, + void (*cb)(void *data, + enum drm_connector_status status), + void *data); +void drm_bridge_hpd_disable(struct drm_bridge *bridge); +void drm_bridge_hpd_notify(struct drm_bridge *bridge, + enum drm_connector_status status); #ifdef CONFIG_DRM_PANEL_BRIDGE struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel); @@ -438,6 +888,7 @@ struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev, struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev, struct drm_panel *panel, u32 connector_type); +struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge); #endif #endif |