name : drm_modeset_helper_vtables.h /* * Copyright © 2006 Keith Packard * Copyright © 2007-2008 Dave Airlie * Copyright © 2007-2008 Intel Corporation * Jesse Barnes <jesse.barnes@intel.com> * Copyright © 2011-2013 Intel Corporation * Copyright © 2015 Intel Corporation * Daniel Vetter <daniel.vetter@ffwll.ch> * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. */ #ifndef __DRM_MODESET_HELPER_VTABLES_H__ #define __DRM_MODESET_HELPER_VTABLES_H__ #include <drm/drm_crtc.h> #include <drm/drm_encoder.h> /** * DOC: overview * * The DRM mode setting helper functions are common code for drivers to use if * they wish. Drivers are not forced to use this code in their * implementations but it would be useful if the code they do use at least * provides a consistent interface and operation to userspace. Therefore it is * highly recommended to use the provided helpers as much as possible. * * Because there is only one pointer per modeset object to hold a vfunc table * for helper libraries they are by necessity shared among the different * helpers. * * To make this clear all the helper vtables are pulled together in this location here. */ struct drm_writeback_connector; struct drm_writeback_job; enum mode_set_atomic { LEAVE_ATOMIC_MODE_SET, ENTER_ATOMIC_MODE_SET, }; /** * struct drm_crtc_helper_funcs - helper operations for CRTCs * * These hooks are used by the legacy CRTC helpers and the new atomic * modesetting helpers. */ struct drm_crtc_helper_funcs { /** * @dpms: * * Callback to control power levels on the CRTC. If the mode passed in * is unsupported, the provider must use the next lowest power level. * This is used by the legacy CRTC helpers to implement DPMS * functionality in drm_helper_connector_dpms(). * * This callback is also used to disable a CRTC by calling it with * DRM_MODE_DPMS_OFF if the @disable hook isn't used. * * This callback is used by the legacy CRTC helpers. Atomic helpers * also support using this hook for enabling and disabling a CRTC to * facilitate transitions to atomic, but it is deprecated. Instead * @atomic_enable and @atomic_disable should be used. */ void (*dpms)(struct drm_crtc *crtc, int mode); /** * @prepare: * * This callback should prepare the CRTC for a subsequent modeset, which * in practice means the driver should disable the CRTC if it is * running. Most drivers ended up implementing this by calling their * @dpms hook with DRM_MODE_DPMS_OFF. * * This callback is used by the legacy CRTC helpers. Atomic helpers * also support using this hook for disabling a CRTC to facilitate * transitions to atomic, but it is deprecated. Instead @atomic_disable * should be used. */ void (*prepare)(struct drm_crtc *crtc); /** * @commit: * * This callback should commit the new mode on the CRTC after a modeset, * which in practice means the driver should enable the CRTC. Most * drivers ended up implementing this by calling their @dpms hook with * DRM_MODE_DPMS_ON. * * This callback is used by the legacy CRTC helpers. Atomic helpers * also support using this hook for enabling a CRTC to facilitate * transitions to atomic, but it is deprecated. Instead @atomic_enable * should be used. */ void (*commit)(struct drm_crtc *crtc); /** * @mode_valid: * * This callback is used to check if a specific mode is valid in this * crtc. This should be implemented if the crtc has some sort of * restriction in the modes it can display. For example, a given crtc * may be responsible to set a clock value. If the clock can not * produce all the values for the available modes then this callback * can be used to restrict the number of modes to only the ones that * can be displayed. * * This hook is used by the probe helpers to filter the mode list in * drm_helper_probe_single_connector_modes(), and it is used by the * atomic helpers to validate modes supplied by userspace in * drm_atomic_helper_check_modeset(). * * This function is optional. * * NOTE: * * Since this function is both called from the check phase of an atomic * commit, and the mode validation in the probe paths it is not allowed * to look at anything else but the passed-in mode, and validate it * against configuration-invariant hardware constraints. Any further * limits which depend upon the configuration can only be checked in * @mode_fixup or @atomic_check. * * RETURNS: * * drm_mode_status Enum */ enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc, const struct drm_display_mode *mode); /** * @mode_fixup: * * This callback is used to validate a mode. The parameter mode is the * display mode that userspace requested, adjusted_mode is the mode the * encoders need to be fed with. Note that this is the inverse semantics * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup * vfunc. If the CRTC cannot support the requested conversion from mode * to adjusted_mode it should reject the modeset. See also * &drm_crtc_state.adjusted_mode for more details. * * This function is used by both legacy CRTC helpers and atomic helpers. * With atomic helpers it is optional. * * NOTE: * * This function is called in the check phase of atomic modesets, which * can be aborted for any reason (including on userspace's request to * just check whether a configuration would be possible). Atomic drivers * MUST NOT touch any persistent state (hardware or software) or data * structures except the passed in adjusted_mode parameter. * * This is in contrast to the legacy CRTC helpers where this was * allowed. * * Atomic drivers which need to inspect and adjust more state should * instead use the @atomic_check callback, but note that they're not * perfectly equivalent: @mode_valid is called from * drm_atomic_helper_check_modeset(), but @atomic_check is called from * drm_atomic_helper_check_planes(), because originally it was meant for * plane update checks only. * * Also beware that userspace can request its own custom modes, neither * core nor helpers filter modes to the list of probe modes reported by * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure * that modes are filtered consistently put any CRTC constraints and * limits checks into @mode_valid. * * RETURNS: * * True if an acceptable configuration is possible, false if the modeset * operation should be rejected. */ bool (*mode_fixup)(struct drm_crtc *crtc, const struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); /** * @mode_set: * * This callback is used by the legacy CRTC helpers to set a new mode, * position and framebuffer. Since it ties the primary plane to every * mode change it is incompatible with universal plane support. And * since it can't update other planes it's incompatible with atomic * modeset support. * * This callback is only used by CRTC helpers and deprecated. * * RETURNS: * * 0 on success or a negative error code on failure. */ int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode, int x, int y, struct drm_framebuffer *old_fb); /** * @mode_set_nofb: * * This callback is used to update the display mode of a CRTC without * changing anything of the primary plane configuration. This fits the * requirement of atomic and hence is used by the atomic helpers. * * Note that the display pipe is completely off when this function is * called. Atomic drivers which need hardware to be running before they * program the new display mode (e.g. because they implement runtime PM) * should not use this hook. This is because the helper library calls * this hook only once per mode change and not every time the display * pipeline is suspended using either DPMS or the new "ACTIVE" property. * Which means register values set in this callback might get reset when * the CRTC is suspended, but not restored. Such drivers should instead * move all their CRTC setup into the @atomic_enable callback. * * This callback is optional. */ void (*mode_set_nofb)(struct drm_crtc *crtc); /** * @mode_set_base: * * This callback is used by the legacy CRTC helpers to set a new * framebuffer and scanout position. It is optional and used as an * optimized fast-path instead of a full mode set operation with all the * resulting flickering. If it is not present * drm_crtc_helper_set_config() will fall back to a full modeset, using * the @mode_set callback. Since it can't update other planes it's * incompatible with atomic modeset support. * * This callback is only used by the CRTC helpers and deprecated. * * RETURNS: * * 0 on success or a negative error code on failure. */ int (*mode_set_base)(struct drm_crtc *crtc, int x, int y, struct drm_framebuffer *old_fb); /** * @mode_set_base_atomic: * * This callback is used by the fbdev helpers to set a new framebuffer * and scanout without sleeping, i.e. from an atomic calling context. It * is only used to implement kgdb support. * * This callback is optional and only needed for kgdb support in the fbdev * helpers. * * RETURNS: * * 0 on success or a negative error code on failure. */ int (*mode_set_base_atomic)(struct drm_crtc *crtc, struct drm_framebuffer *fb, int x, int y, enum mode_set_atomic); /** * @disable: * * This callback should be used to disable the CRTC. With the atomic * drivers it is called after all encoders connected to this CRTC have * been shut off already using their own * &drm_encoder_helper_funcs.disable hook. If that sequence is too * simple drivers can just add their own hooks and call it from this * CRTC callback here by looping over all encoders connected to it using * for_each_encoder_on_crtc(). * * This hook is used both by legacy CRTC helpers and atomic helpers. * Atomic drivers don't need to implement it if there's no need to * disable anything at the CRTC level. To ensure that runtime PM * handling (using either DPMS or the new "ACTIVE" property) works * @disable must be the inverse of @atomic_enable for atomic drivers. * Atomic drivers should consider to use @atomic_disable instead of * this one. * * NOTE: * * With legacy CRTC helpers there's a big semantic difference between * @disable and other hooks (like @prepare or @dpms) used to shut down a * CRTC: @disable is only called when also logically disabling the * display pipeline and needs to release any resources acquired in * @mode_set (like shared PLLs, or again release pinned framebuffers). * * Therefore @disable must be the inverse of @mode_set plus @commit for * drivers still using legacy CRTC helpers, which is different from the * rules under atomic. */ void (*disable)(struct drm_crtc *crtc); /** * @atomic_check: * * Drivers should check plane-update related CRTC constraints in this * hook. They can also check mode related limitations but need to be * aware of the calling order, since this hook is used by * drm_atomic_helper_check_planes() whereas the preparations needed to * check output routing and the display mode is done in * drm_atomic_helper_check_modeset(). Therefore drivers that want to * check output routing and display mode constraints in this callback * must ensure that drm_atomic_helper_check_modeset() has been called * beforehand. This is calling order used by the default helper * implementation in drm_atomic_helper_check(). * * When using drm_atomic_helper_check_planes() this hook is called * after the &drm_plane_helper_funcs.atomic_check hook for planes, which * allows drivers to assign shared resources requested by planes in this * callback here. For more complicated dependencies the driver can call * the provided check helpers multiple times until the computed state * has a final configuration and everything has been checked. * * This function is also allowed to inspect any other object's state and * can add more state objects to the atomic commit if needed. Care must * be taken though to ensure that state check and compute functions for * these added states are all called, and derived state in other objects * all updated. Again the recommendation is to just call check helpers * until a maximal configuration is reached. * * This callback is used by the atomic modeset helpers, but it is * optional. * * NOTE: * * This function is called in the check phase of an atomic update. The * driver is not allowed to change anything outside of the free-standing * state object passed-in. * * Also beware that userspace can request its own custom modes, neither * core nor helpers filter modes to the list of probe modes reported by * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure * that modes are filtered consistently put any CRTC constraints and * limits checks into @mode_valid. * * RETURNS: * * 0 on success, -EINVAL if the state or the transition can't be * supported, -ENOMEM on memory allocation failure and -EDEADLK if an * attempt to obtain another state object ran into a &drm_modeset_lock * deadlock. */ int (*atomic_check)(struct drm_crtc *crtc, struct drm_atomic_state *state); /** * @atomic_begin: * * Drivers should prepare for an atomic update of multiple planes on * a CRTC in this hook. Depending upon hardware this might be vblank * evasion, blocking updates by setting bits or doing preparatory work * for e.g. manual update display. * * This hook is called before any plane commit functions are called. * * Note that the power state of the display pipe when this function is * called depends upon the exact helpers and calling sequence the driver * has picked. See drm_atomic_helper_commit_planes() for a discussion of * the tradeoffs and variants of plane commit helpers. * * This callback is used by the atomic modeset helpers, but it is * optional. */ void (*atomic_begin)(struct drm_crtc *crtc, struct drm_atomic_state *state); /** * @atomic_flush: * * Drivers should finalize an atomic update of multiple planes on * a CRTC in this hook. Depending upon hardware this might include * checking that vblank evasion was successful, unblocking updates by * setting bits or setting the GO bit to flush out all updates. * * Simple hardware or hardware with special requirements can commit and * flush out all updates for all planes from this hook and forgo all the * other commit hooks for plane updates. * * This hook is called after any plane commit functions are called. * * Note that the power state of the display pipe when this function is * called depends upon the exact helpers and calling sequence the driver * has picked. See drm_atomic_helper_commit_planes() for a discussion of * the tradeoffs and variants of plane commit helpers. * * This callback is used by the atomic modeset helpers, but it is * optional. */ void (*atomic_flush)(struct drm_crtc *crtc, struct drm_atomic_state *state); /** * @atomic_enable: * * This callback should be used to enable the CRTC. With the atomic * drivers it is called before all encoders connected to this CRTC are * enabled through the encoder's own &drm_encoder_helper_funcs.enable * hook. If that sequence is too simple drivers can just add their own * hooks and call it from this CRTC callback here by looping over all * encoders connected to it using for_each_encoder_on_crtc(). * * This hook is used only by atomic helpers, for symmetry with * @atomic_disable. Atomic drivers don't need to implement it if there's * no need to enable anything at the CRTC level. To ensure that runtime * PM handling (using either DPMS or the new "ACTIVE" property) works * @atomic_enable must be the inverse of @atomic_disable for atomic * drivers. * * This function is optional. */ void (*atomic_enable)(struct drm_crtc *crtc, struct drm_atomic_state *state); /** * @atomic_disable: * * This callback should be used to disable the CRTC. With the atomic * drivers it is called after all encoders connected to this CRTC have * been shut off already using their own * &drm_encoder_helper_funcs.disable hook. If that sequence is too * simple drivers can just add their own hooks and call it from this * CRTC callback here by looping over all encoders connected to it using * for_each_encoder_on_crtc(). * * This hook is used only by atomic helpers. Atomic drivers don't * need to implement it if there's no need to disable anything at the * CRTC level. * * This function is optional. */ void (*atomic_disable)(struct drm_crtc *crtc, struct drm_atomic_state *state); /** * @get_scanout_position: * * Called by vblank timestamping code. * * Returns the current display scanout position from a CRTC and an * optional accurate ktime_get() timestamp of when the position was * measured. Note that this is a helper callback which is only used * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp() * for the @drm_crtc_funcs.get_vblank_timestamp callback. * * Parameters: * * crtc: * The CRTC. * in_vblank_irq: * True when called from drm_crtc_handle_vblank(). Some drivers * need to apply some workarounds for gpu-specific vblank irq * quirks if the flag is set. * vpos: * Target location for current vertical scanout position. * hpos: * Target location for current horizontal scanout position. * stime: * Target location for timestamp taken immediately before * scanout position query. Can be NULL to skip timestamp. * etime: * Target location for timestamp taken immediately after * scanout position query. Can be NULL to skip timestamp. * mode: * Current display timings. * * Returns vpos as a positive number while in active scanout area. * Returns vpos as a negative number inside vblank, counting the number * of scanlines to go until end of vblank, e.g., -1 means "one scanline * until start of active scanout / end of vblank." * * Returns: * * True on success, false if a reliable scanout position counter could * not be read out. */ bool (*get_scanout_position)(struct drm_crtc *crtc, bool in_vblank_irq, int *vpos, int *hpos, ktime_t *stime, ktime_t *etime, const struct drm_display_mode *mode); }; /** * drm_crtc_helper_add - sets the helper vtable for a crtc * @crtc: DRM CRTC * @funcs: helper vtable to set for @crtc */ static inline void drm_crtc_helper_add(struct drm_crtc *crtc, const struct drm_crtc_helper_funcs *funcs) { crtc->helper_private = funcs; } /** * struct drm_encoder_helper_funcs - helper operations for encoders * * These hooks are used by the legacy CRTC helpers and the new atomic * modesetting helpers. */ struct drm_encoder_helper_funcs { /** * @dpms: * * Callback to control power levels on the encoder. If the mode passed in * is unsupported, the provider must use the next lowest power level. * This is used by the legacy encoder helpers to implement DPMS * functionality in drm_helper_connector_dpms(). * * This callback is also used to disable an encoder by calling it with * DRM_MODE_DPMS_OFF if the @disable hook isn't used. * * This callback is used by the legacy CRTC helpers. Atomic helpers * also support using this hook for enabling and disabling an encoder to * facilitate transitions to atomic, but it is deprecated. Instead * @enable and @disable should be used. */ void (*dpms)(struct drm_encoder *encoder, int mode); /** * @mode_valid: * * This callback is used to check if a specific mode is valid in this * encoder. This should be implemented if the encoder has some sort * of restriction in the modes it can display. For example, a given * encoder may be responsible to set a clock value. If the clock can * not produce all the values for the available modes then this callback * can be used to restrict the number of modes to only the ones that * can be displayed. * * This hook is used by the probe helpers to filter the mode list in * drm_helper_probe_single_connector_modes(), and it is used by the * atomic helpers to validate modes supplied by userspace in * drm_atomic_helper_check_modeset(). * * This function is optional. * * NOTE: * * Since this function is both called from the check phase of an atomic * commit, and the mode validation in the probe paths it is not allowed * to look at anything else but the passed-in mode, and validate it * against configuration-invariant hardware constraints. Any further * limits which depend upon the configuration can only be checked in * @mode_fixup or @atomic_check. * * RETURNS: * * drm_mode_status Enum */ enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc, const struct drm_display_mode *mode); /** * @mode_fixup: * * This callback is used to validate and adjust a mode. The parameter * mode is the display mode that should be fed to the next element in * the display chain, either the final &drm_connector or a &drm_bridge. * The parameter adjusted_mode is the input mode the encoder requires. It * can be modified by this callback and does not need to match mode. See * also &drm_crtc_state.adjusted_mode for more details. * * This function is used by both legacy CRTC helpers and atomic helpers. * This hook is optional. * * NOTE: * * This function is called in the check phase of atomic modesets, which * can be aborted for any reason (including on userspace's request to * just check whether a configuration would be possible). Atomic drivers * MUST NOT touch any persistent state (hardware or software) or data * structures except the passed in adjusted_mode parameter. * * This is in contrast to the legacy CRTC helpers where this was * allowed. * * Atomic drivers which need to inspect and adjust more state should * instead use the @atomic_check callback. If @atomic_check is used, * this hook isn't called since @atomic_check allows a strict superset * of the functionality of @mode_fixup. * * Also beware that userspace can request its own custom modes, neither * core nor helpers filter modes to the list of probe modes reported by * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure * that modes are filtered consistently put any encoder constraints and * limits checks into @mode_valid. * * RETURNS: * * True if an acceptable configuration is possible, false if the modeset * operation should be rejected. */ bool (*mode_fixup)(struct drm_encoder *encoder, const struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); /** * @prepare: * * This callback should prepare the encoder for a subsequent modeset, * which in practice means the driver should disable the encoder if it * is running. Most drivers ended up implementing this by calling their * @dpms hook with DRM_MODE_DPMS_OFF. * * This callback is used by the legacy CRTC helpers. Atomic helpers * also support using this hook for disabling an encoder to facilitate * transitions to atomic, but it is deprecated. Instead @disable should * be used. */ void (*prepare)(struct drm_encoder *encoder); /** * @commit: * * This callback should commit the new mode on the encoder after a modeset, * which in practice means the driver should enable the encoder. Most * drivers ended up implementing this by calling their @dpms hook with * DRM_MODE_DPMS_ON. * * This callback is used by the legacy CRTC helpers. Atomic helpers * also support using this hook for enabling an encoder to facilitate * transitions to atomic, but it is deprecated. Instead @enable should * be used. */ void (*commit)(struct drm_encoder *encoder); /** * @mode_set: * * This callback is used to update the display mode of an encoder. * * Note that the display pipe is completely off when this function is * called. Drivers which need hardware to be running before they program * the new display mode (because they implement runtime PM) should not * use this hook, because the helper library calls it only once and not * every time the display pipeline is suspend using either DPMS or the * new "ACTIVE" property. Such drivers should instead move all their * encoder setup into the @enable callback. * * This callback is used both by the legacy CRTC helpers and the atomic * modeset helpers. It is optional in the atomic helpers. * * NOTE: * * If the driver uses the atomic modeset helpers and needs to inspect * the connector state or connector display info during mode setting, * @atomic_mode_set can be used instead. */ void (*mode_set)(struct drm_encoder *encoder, struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); /** * @atomic_mode_set: * * This callback is used to update the display mode of an encoder. * * Note that the display pipe is completely off when this function is * called. Drivers which need hardware to be running before they program * the new display mode (because they implement runtime PM) should not * use this hook, because the helper library calls it only once and not * every time the display pipeline is suspended using either DPMS or the * new "ACTIVE" property. Such drivers should instead move all their * encoder setup into the @enable callback. * * This callback is used by the atomic modeset helpers in place of the * @mode_set callback, if set by the driver. It is optional and should * be used instead of @mode_set if the driver needs to inspect the * connector state or display info, since there is no direct way to * go from the encoder to the current connector. */ void (*atomic_mode_set)(struct drm_encoder *encoder, struct drm_crtc_state *crtc_state, struct drm_connector_state *conn_state); /** * @detect: * * This callback can be used by drivers who want to do detection on the * encoder object instead of in connector functions. * * It is not used by any helper and therefore has purely driver-specific * semantics. New drivers shouldn't use this and instead just implement * their own private callbacks. * * FIXME: * * This should just be converted into a pile of driver vfuncs. * Currently radeon, amdgpu and nouveau are using it. */ enum drm_connector_status (*detect)(struct drm_encoder *encoder, struct drm_connector *connector); /** * @atomic_disable: * * This callback should be used to disable the encoder. With the atomic * drivers it is called before this encoder's CRTC has been shut off * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that * sequence is too simple drivers can just add their own driver private * encoder hooks and call them from CRTC's callback by looping over all * encoders connected to it using for_each_encoder_on_crtc(). * * This callback is a variant of @disable that provides the atomic state * to the driver. If @atomic_disable is implemented, @disable is not * called by the helpers. * * This hook is only used by atomic helpers. Atomic drivers don't need * to implement it if there's no need to disable anything at the encoder * level. To ensure that runtime PM handling (using either DPMS or the * new "ACTIVE" property) works @atomic_disable must be the inverse of * @atomic_enable. */ void (*atomic_disable)(struct drm_encoder *encoder, struct drm_atomic_state *state); /** * @atomic_enable: * * This callback should be used to enable the encoder. It is called * after this encoder's CRTC has been enabled using their own * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is * too simple drivers can just add their own driver private encoder * hooks and call them from CRTC's callback by looping over all encoders * connected to it using for_each_encoder_on_crtc(). * * This callback is a variant of @enable that provides the atomic state * to the driver. If @atomic_enable is implemented, @enable is not * called by the helpers. * * This hook is only used by atomic helpers, it is the opposite of * @atomic_disable. Atomic drivers don't need to implement it if there's * no need to enable anything at the encoder level. To ensure that * runtime PM handling works @atomic_enable must be the inverse of * @atomic_disable. */ void (*atomic_enable)(struct drm_encoder *encoder, struct drm_atomic_state *state); /** * @disable: * * This callback should be used to disable the encoder. With the atomic * drivers it is called before this encoder's CRTC has been shut off * using their own &drm_crtc_helper_funcs.disable hook. If that * sequence is too simple drivers can just add their own driver private * encoder hooks and call them from CRTC's callback by looping over all * encoders connected to it using for_each_encoder_on_crtc(). * * This hook is used both by legacy CRTC helpers and atomic helpers. * Atomic drivers don't need to implement it if there's no need to * disable anything at the encoder level. To ensure that runtime PM * handling (using either DPMS or the new "ACTIVE" property) works * @disable must be the inverse of @enable for atomic drivers. * * For atomic drivers also consider @atomic_disable and save yourself * from having to read the NOTE below! * * NOTE: * * With legacy CRTC helpers there's a big semantic difference between * @disable and other hooks (like @prepare or @dpms) used to shut down a * encoder: @disable is only called when also logically disabling the * display pipeline and needs to release any resources acquired in * @mode_set (like shared PLLs, or again release pinned framebuffers). * * Therefore @disable must be the inverse of @mode_set plus @commit for * drivers still using legacy CRTC helpers, which is different from the * rules under atomic. */ void (*disable)(struct drm_encoder *encoder); /** * @enable: * * This callback should be used to enable the encoder. With the atomic * drivers it is called after this encoder's CRTC has been enabled using * their own &drm_crtc_helper_funcs.enable hook. If that sequence is * too simple drivers can just add their own driver private encoder * hooks and call them from CRTC's callback by looping over all encoders * connected to it using for_each_encoder_on_crtc(). * * This hook is only used by atomic helpers, it is the opposite of * @disable. Atomic drivers don't need to implement it if there's no * need to enable anything at the encoder level. To ensure that * runtime PM handling (using either DPMS or the new "ACTIVE" property) * works @enable must be the inverse of @disable for atomic drivers. */ void (*enable)(struct drm_encoder *encoder); /** * @atomic_check: * * This callback is used to validate encoder state for atomic drivers. * Since the encoder is the object connecting the CRTC and connector it * gets passed both states, to be able to validate interactions and * update the CRTC to match what the encoder needs for the requested * connector. * * Since this provides a strict superset of the functionality of * @mode_fixup (the requested and adjusted modes are both available * through the passed in &struct drm_crtc_state) @mode_fixup is not * called when @atomic_check is implemented. * * This function is used by the atomic helpers, but it is optional. * * NOTE: * * This function is called in the check phase of an atomic update. The * driver is not allowed to change anything outside of the free-standing * state objects passed-in or assembled in the overall &drm_atomic_state * update tracking structure. * * Also beware that userspace can request its own custom modes, neither * core nor helpers filter modes to the list of probe modes reported by * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure * that modes are filtered consistently put any encoder constraints and * limits checks into @mode_valid. * * RETURNS: * * 0 on success, -EINVAL if the state or the transition can't be * supported, -ENOMEM on memory allocation failure and -EDEADLK if an * attempt to obtain another state object ran into a &drm_modeset_lock * deadlock. */ int (*atomic_check)(struct drm_encoder *encoder, struct drm_crtc_state *crtc_state, struct drm_connector_state *conn_state); }; /** * drm_encoder_helper_add - sets the helper vtable for an encoder * @encoder: DRM encoder * @funcs: helper vtable to set for @encoder */ static inline void drm_encoder_helper_add(struct drm_encoder *encoder, const struct drm_encoder_helper_funcs *funcs) { encoder->helper_private = funcs; } /** * struct drm_connector_helper_funcs - helper operations for connectors * * These functions are used by the atomic and legacy modeset helpers and by the * probe helpers. */ struct drm_connector_helper_funcs { /** * @get_modes: * * This function should fill in all modes currently valid for the sink * into the &drm_connector.probed_modes list. It should also update the * EDID property by calling drm_connector_update_edid_property(). * * The usual way to implement this is to cache the EDID retrieved in the * probe callback somewhere in the driver-private connector structure. * In this function drivers then parse the modes in the EDID and add * them by calling drm_add_edid_modes(). But connectors that drive a * fixed panel can also manually add specific modes using * drm_mode_probed_add(). Drivers which manually add modes should also * make sure that the &drm_connector.display_info, * &drm_connector.width_mm and &drm_connector.height_mm fields are * filled in. * * Note that the caller function will automatically add standard VESA * DMT modes up to 1024x768 if the .get_modes() helper operation returns * no mode and if the connector status is connector_status_connected or * connector_status_unknown. There is no need to call * drm_add_modes_noedid() manually in that case. * * Virtual drivers that just want some standard VESA mode with a given * resolution can call drm_add_modes_noedid(), and mark the preferred * one using drm_set_preferred_mode(). * * This function is only called after the @detect hook has indicated * that a sink is connected and when the EDID isn't overridden through * sysfs or the kernel commandline. * * This callback is used by the probe helpers in e.g. * drm_helper_probe_single_connector_modes(). * * To avoid races with concurrent connector state updates, the helper * libraries always call this with the &drm_mode_config.connection_mutex * held. Because of this it's safe to inspect &drm_connector->state. * * RETURNS: * * The number of modes added by calling drm_mode_probed_add(). Return 0 * on failures (no modes) instead of negative error codes. */ int (*get_modes)(struct drm_connector *connector); /** * @detect_ctx: * * Check to see if anything is attached to the connector. The parameter * force is set to false whilst polling, true when checking the * connector due to a user request. force can be used by the driver to * avoid expensive, destructive operations during automated probing. * * This callback is optional, if not implemented the connector will be * considered as always being attached. * * This is the atomic version of &drm_connector_funcs.detect. * * To avoid races against concurrent connector state updates, the * helper libraries always call this with ctx set to a valid context, * and &drm_mode_config.connection_mutex will always be locked with * the ctx parameter set to this ctx. This allows taking additional * locks as required. * * RETURNS: * * &drm_connector_status indicating the connector's status, * or the error code returned by drm_modeset_lock(), -EDEADLK. */ int (*detect_ctx)(struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, bool force); /** * @mode_valid: * * Callback to validate a mode for a connector, irrespective of the * specific display configuration. * * This callback is used by the probe helpers to filter the mode list * (which is usually derived from the EDID data block from the sink). * See e.g. drm_helper_probe_single_connector_modes(). * * This function is optional. * * NOTE: * * This only filters the mode list supplied to userspace in the * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid, * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid, * which are also called by the atomic helpers from * drm_atomic_helper_check_modeset(). This allows userspace to force and * ignore sink constraint (like the pixel clock limits in the screen's * EDID), which is useful for e.g. testing, or working around a broken * EDID. Any source hardware constraint (which always need to be * enforced) therefore should be checked in one of the above callbacks, * and not this one here. * * To avoid races with concurrent connector state updates, the helper * libraries always call this with the &drm_mode_config.connection_mutex * held. Because of this it's safe to inspect &drm_connector->state. * * RETURNS: * * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum * drm_mode_status. */ enum drm_mode_status (*mode_valid)(struct drm_connector *connector, struct drm_display_mode *mode); /** * @mode_valid_ctx: * * Callback to validate a mode for a connector, irrespective of the * specific display configuration. * * This callback is used by the probe helpers to filter the mode list * (which is usually derived from the EDID data block from the sink). * See e.g. drm_helper_probe_single_connector_modes(). * * This function is optional, and is the atomic version of * &drm_connector_helper_funcs.mode_valid. * * To allow for accessing the atomic state of modesetting objects, the * helper libraries always call this with ctx set to a valid context, * and &drm_mode_config.connection_mutex will always be locked with * the ctx parameter set to @ctx. This allows for taking additional * locks as required. * * Even though additional locks may be acquired, this callback is * still expected not to take any constraints into account which would * be influenced by the currently set display state - such constraints * should be handled in the driver's atomic check. For example, if a * connector shares display bandwidth with other connectors then it * would be ok to validate the minimum bandwidth requirement of a mode * against the maximum possible bandwidth of the connector. But it * wouldn't be ok to take the current bandwidth usage of other * connectors into account, as this would change depending on the * display state. * * Returns: * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote * the &enum drm_mode_status value to @status, or a negative error * code otherwise. * */ int (*mode_valid_ctx)(struct drm_connector *connector, struct drm_display_mode *mode, struct drm_modeset_acquire_ctx *ctx, enum drm_mode_status *status); /** * @best_encoder: * * This function should select the best encoder for the given connector. * * This function is used by both the atomic helpers (in the * drm_atomic_helper_check_modeset() function) and in the legacy CRTC * helpers. * * NOTE: * * In atomic drivers this function is called in the check phase of an * atomic update. The driver is not allowed to change or inspect * anything outside of arguments passed-in. Atomic drivers which need to * inspect dynamic configuration state should instead use * @atomic_best_encoder. * * You can leave this function to NULL if the connector is only * attached to a single encoder. In this case, the core will call * drm_connector_get_single_encoder() for you. * * RETURNS: * * Encoder that should be used for the given connector and connector * state, or NULL if no suitable encoder exists. Note that the helpers * will ensure that encoders aren't used twice, drivers should not check * for this. */ struct drm_encoder *(*best_encoder)(struct drm_connector *connector); /** * @atomic_best_encoder: * * This is the atomic version of @best_encoder for atomic drivers which * need to select the best encoder depending upon the desired * configuration and can't select it statically. * * This function is used by drm_atomic_helper_check_modeset(). * If it is not implemented, the core will fallback to @best_encoder * (or drm_connector_get_single_encoder() if @best_encoder is NULL). * * NOTE: * * This function is called in the check phase of an atomic update. The * driver is not allowed to change anything outside of the * &drm_atomic_state update tracking structure passed in. * * RETURNS: * * Encoder that should be used for the given connector and connector * state, or NULL if no suitable encoder exists. Note that the helpers * will ensure that encoders aren't used twice, drivers should not check * for this. */ struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, struct drm_atomic_state *state); /** * @atomic_check: * * This hook is used to validate connector state. This function is * called from &drm_atomic_helper_check_modeset, and is called when * a connector property is set, or a modeset on the crtc is forced. * * Because &drm_atomic_helper_check_modeset may be called multiple times, * this function should handle being called multiple times as well. * * This function is also allowed to inspect any other object's state and * can add more state objects to the atomic commit if needed. Care must * be taken though to ensure that state check and compute functions for * these added states are all called, and derived state in other objects * all updated. Again the recommendation is to just call check helpers * until a maximal configuration is reached. * * NOTE: * * This function is called in the check phase of an atomic update. The * driver is not allowed to change anything outside of the free-standing * state objects passed-in or assembled in the overall &drm_atomic_state * update tracking structure. * * RETURNS: * * 0 on success, -EINVAL if the state or the transition can't be * supported, -ENOMEM on memory allocation failure and -EDEADLK if an * attempt to obtain another state object ran into a &drm_modeset_lock * deadlock. */ int (*atomic_check)(struct drm_connector *connector, struct drm_atomic_state *state); /** * @atomic_commit: * * This hook is to be used by drivers implementing writeback connectors * that need a point when to commit the writeback job to the hardware. * The writeback_job to commit is available in the new connector state, * in &drm_connector_state.writeback_job. * * This hook is optional. * * This callback is used by the atomic modeset helpers. */ void (*atomic_commit)(struct drm_connector *connector, struct drm_atomic_state *state); /** * @prepare_writeback_job: * * As writeback jobs contain a framebuffer, drivers may need to * prepare and clean them up the same way they can prepare and * clean up framebuffers for planes. This optional connector operation * is used to support the preparation of writeback jobs. The job * prepare operation is called from drm_atomic_helper_prepare_planes() * for struct &drm_writeback_connector connectors only. * * This operation is optional. * * This callback is used by the atomic modeset helpers. */ int (*prepare_writeback_job)(struct drm_writeback_connector *connector, struct drm_writeback_job *job); /** * @cleanup_writeback_job: * * This optional connector operation is used to support the * cleanup of writeback jobs. The job cleanup operation is called * from the existing drm_writeback_cleanup_job() function, invoked * both when destroying the job as part of an aborted commit, or when * the job completes. * * This operation is optional. * * This callback is used by the atomic modeset helpers. */ void (*cleanup_writeback_job)(struct drm_writeback_connector *connector, struct drm_writeback_job *job); /** * @enable_hpd: * * Enable hot-plug detection for the connector. * * This operation is optional. * * This callback is used by the drm_kms_helper_poll_enable() helpers. * * This operation does not need to perform any hpd state tracking as * the DRM core handles that maintenance and ensures the calls to enable * and disable hpd are balanced. * */ void (*enable_hpd)(struct drm_connector *connector); /** * @disable_hpd: * * Disable hot-plug detection for the connector. * * This operation is optional. * * This callback is used by the drm_kms_helper_poll_disable() helpers. * * This operation does not need to perform any hpd state tracking as * the DRM core handles that maintenance and ensures the calls to enable * and disable hpd are balanced. * */ void (*disable_hpd)(struct drm_connector *connector); }; /** * drm_connector_helper_add - sets the helper vtable for a connector * @connector: DRM connector * @funcs: helper vtable to set for @connector */ static inline void drm_connector_helper_add(struct drm_connector *connector, const struct drm_connector_helper_funcs *funcs) { connector->helper_private = funcs; } /** * struct drm_plane_helper_funcs - helper operations for planes * * These functions are used by the atomic helpers. */ struct drm_plane_helper_funcs { /** * @prepare_fb: * * This hook is to prepare a framebuffer for scanout by e.g. pinning * its backing storage or relocating it into a contiguous block of * VRAM. Other possible preparatory work includes flushing caches. * * This function must not block for outstanding rendering, since it is * called in the context of the atomic IOCTL even for async commits to * be able to return any errors to userspace. Instead the recommended * way is to fill out the &drm_plane_state.fence of the passed-in * &drm_plane_state. If the driver doesn't support native fences then * equivalent functionality should be implemented through private * members in the plane structure. * * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook * set drm_gem_plane_helper_prepare_fb() is called automatically to * implement this. Other drivers which need additional plane processing * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb * hook. * * The resources acquired in @prepare_fb persist after the end of * the atomic commit. Resources that can be release at the commit's end * should be acquired in @begin_fb_access and released in @end_fb_access. * For example, a GEM buffer's pin operation belongs into @prepare_fb to * keep the buffer pinned after the commit. But a vmap operation for * shadow-plane helpers belongs into @begin_fb_access, so that atomic * helpers remove the mapping at the end of the commit. * * The helpers will call @cleanup_fb with matching arguments for every * successful call to this hook. * * This callback is used by the atomic modeset helpers, but it is * optional. See @begin_fb_access for preparing per-commit resources. * * RETURNS: * * 0 on success or one of the following negative error codes allowed by * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers * this callback is the only one which can fail an atomic commit, * everything else must complete successfully. */ int (*prepare_fb)(struct drm_plane *plane, struct drm_plane_state *new_state); /** * @cleanup_fb: * * This hook is called to clean up any resources allocated for the given * framebuffer and plane configuration in @prepare_fb. * * This callback is used by the atomic modeset helpers, but it is * optional. */ void (*cleanup_fb)(struct drm_plane *plane, struct drm_plane_state *old_state); /** * @begin_fb_access: * * This hook prepares the plane for access during an atomic commit. * In contrast to @prepare_fb, resources acquired in @begin_fb_access, * are released at the end of the atomic commit in @end_fb_access. * * For example, with shadow-plane helpers, the GEM buffer's vmap * operation belongs into @begin_fb_access, so that the buffer's * memory will be unmapped at the end of the commit in @end_fb_access. * But a GEM buffer's pin operation belongs into @prepare_fb * to keep the buffer pinned after the commit. * * The callback is used by the atomic modeset helpers, but it is optional. * See @end_fb_cleanup for undoing the effects of @begin_fb_access and * @prepare_fb for acquiring resources until the next pageflip. * * Returns: * 0 on success, or a negative errno code otherwise. */ int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state); /** * @end_fb_access: * * This hook cleans up resources allocated by @begin_fb_access. It it called * at the end of a commit for the new plane state. */ void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state); /** * @atomic_check: * * Drivers should check plane specific constraints in this hook. * * When using drm_atomic_helper_check_planes() plane's @atomic_check * hooks are called before the ones for CRTCs, which allows drivers to * request shared resources that the CRTC controls here. For more * complicated dependencies the driver can call the provided check helpers * multiple times until the computed state has a final configuration and * everything has been checked. * * This function is also allowed to inspect any other object's state and * can add more state objects to the atomic commit if needed. Care must * be taken though to ensure that state check and compute functions for * these added states are all called, and derived state in other objects * all updated. Again the recommendation is to just call check helpers * until a maximal configuration is reached. * * This callback is used by the atomic modeset helpers, but it is * optional. * * NOTE: * * This function is called in the check phase of an atomic update. The * driver is not allowed to change anything outside of the * &drm_atomic_state update tracking structure. * * RETURNS: * * 0 on success, -EINVAL if the state or the transition can't be * supported, -ENOMEM on memory allocation failure and -EDEADLK if an * attempt to obtain another state object ran into a &drm_modeset_lock * deadlock. */ int (*atomic_check)(struct drm_plane *plane, struct drm_atomic_state *state); /** * @atomic_update: * * Drivers should use this function to update the plane state. This * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and * drm_crtc_helper_funcs.atomic_flush callbacks. * * Note that the power state of the display pipe when this function is * called depends upon the exact helpers and calling sequence the driver * has picked. See drm_atomic_helper_commit_planes() for a discussion of * the tradeoffs and variants of plane commit helpers. * * This callback is used by the atomic modeset helpers, but it is optional. */ void (*atomic_update)(struct drm_plane *plane, struct drm_atomic_state *state); /** * @atomic_enable: * * Drivers should use this function to unconditionally enable a plane. * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after * @atomic_update, which will be called for all enabled planes. Drivers * that use @atomic_enable should set up a plane in @atomic_update and * afterwards enable the plane in @atomic_enable. If a plane needs to be * enabled before installing the scanout buffer, drivers can still do * so in @atomic_update. * * Note that the power state of the display pipe when this function is * called depends upon the exact helpers and calling sequence the driver * has picked. See drm_atomic_helper_commit_planes() for a discussion of * the tradeoffs and variants of plane commit helpers. * * This callback is used by the atomic modeset helpers, but it is * optional. If implemented, @atomic_enable should be the inverse of * @atomic_disable. Drivers that don't want to use either can still * implement the complete plane update in @atomic_update. */ void (*atomic_enable)(struct drm_plane *plane, struct drm_atomic_state *state); /** * @atomic_disable: * * Drivers should use this function to unconditionally disable a plane. * This hook is called in-between the * &drm_crtc_helper_funcs.atomic_begin and * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to * @atomic_update, which will be called for disabling planes, too, if * the @atomic_disable hook isn't implemented. * * This hook is also useful to disable planes in preparation of a modeset, * by calling drm_atomic_helper_disable_planes_on_crtc() from the * &drm_crtc_helper_funcs.disable hook. * * Note that the power state of the display pipe when this function is * called depends upon the exact helpers and calling sequence the driver * has picked. See drm_atomic_helper_commit_planes() for a discussion of * the tradeoffs and variants of plane commit helpers. * * This callback is used by the atomic modeset helpers, but it is * optional. It's intended to reverse the effects of @atomic_enable. */ void (*atomic_disable)(struct drm_plane *plane, struct drm_atomic_state *state); /** * @atomic_async_check: * * Drivers should set this function pointer to check if the plane's * atomic state can be updated in a async fashion. Here async means * "not vblank synchronized". * * This hook is called by drm_atomic_async_check() to establish if a * given update can be committed asynchronously, that is, if it can * jump ahead of the state currently queued for update. * * RETURNS: * * Return 0 on success and any error returned indicates that the update * can not be applied in asynchronous manner. */ int (*atomic_async_check)(struct drm_plane *plane, struct drm_atomic_state *state); /** * @atomic_async_update: * * Drivers should set this function pointer to perform asynchronous * updates of planes, that is, jump ahead of the currently queued * state and update the plane. Here async means "not vblank * synchronized". * * This hook is called by drm_atomic_helper_async_commit(). * * An async update will happen on legacy cursor updates. An async * update won't happen if there is an outstanding commit modifying * the same plane. * * When doing async_update drivers shouldn't replace the * &drm_plane_state but update the current one with the new plane * configurations in the new plane_state. * * Drivers should also swap the framebuffers between current plane * state (&drm_plane.state) and new_state. * This is required since cleanup for async commits is performed on * the new state, rather than old state like for traditional commits. * Since we want to give up the reference on the current (old) fb * instead of our brand new one, swap them in the driver during the * async commit. * * FIXME: * - It only works for single plane updates * - Async Pageflips are not supported yet * - Some hw might still scan out the old buffer until the next * vblank, however we let go of the fb references as soon as * we run this hook. For now drivers must implement their own workers * for deferring if needed, until a common solution is created. */ void (*atomic_async_update)(struct drm_plane *plane, struct drm_atomic_state *state); }; /** * drm_plane_helper_add - sets the helper vtable for a plane * @plane: DRM plane * @funcs: helper vtable to set for @plane */ static inline void drm_plane_helper_add(struct drm_plane *plane, const struct drm_plane_helper_funcs *funcs) { plane->helper_private = funcs; } /** * struct drm_mode_config_helper_funcs - global modeset helper operations * * These helper functions are used by the atomic helpers. */ struct drm_mode_config_helper_funcs { /** * @atomic_commit_tail: * * This hook is used by the default atomic_commit() hook implemented in * drm_atomic_helper_commit() together with the nonblocking commit * helpers (see drm_atomic_helper_setup_commit() for a starting point) * to implement blocking and nonblocking commits easily. It is not used * by the atomic helpers * * This function is called when the new atomic state has already been * swapped into the various state pointers. The passed in state * therefore contains copies of the old/previous state. This hook should * commit the new state into hardware. Note that the helpers have * already waited for preceding atomic commits and fences, but drivers * can add more waiting calls at the start of their implementation, e.g. * to wait for driver-internal request for implicit syncing, before * starting to commit the update to the hardware. * * After the atomic update is committed to the hardware this hook needs * to call drm_atomic_helper_commit_hw_done(). Then wait for the update * to be executed by the hardware, for example using * drm_atomic_helper_wait_for_vblanks() or * drm_atomic_helper_wait_for_flip_done(), and then clean up the old * framebuffers using drm_atomic_helper_cleanup_planes(). * * When disabling a CRTC this hook _must_ stall for the commit to * complete. Vblank waits don't work on disabled CRTC, hence the core * can't take care of this. And it also can't rely on the vblank event, * since that can be signalled already when the screen shows black, * which can happen much earlier than the last hardware access needed to * shut off the display pipeline completely. * * This hook is optional, the default implementation is * drm_atomic_helper_commit_tail(). */ void (*atomic_commit_tail)(struct drm_atomic_state *state); /** * @atomic_commit_setup: * * This hook is used by the default atomic_commit() hook implemented in * drm_atomic_helper_commit() together with the nonblocking helpers (see * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It * is not used by the atomic helpers. * * This function is called at the end of * drm_atomic_helper_setup_commit(), so once the commit has been * properly setup across the generic DRM object states. It allows * drivers to do some additional commit tracking that isn't related to a * CRTC, plane or connector, tracked in a &drm_private_obj structure. * * Note that the documentation of &drm_private_obj has more details on * how one should implement this. * * This hook is optional. */ int (*atomic_commit_setup)(struct drm_atomic_state *state); }; #endif