/*
* 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>
/**
* 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.
*/
enum mode_set_atomic;
/**
* struct drm_crtc_helper_funcs - helper operations for CRTCs
*
* These hooks are used by the legacy CRTC helpers, the transitional plane
* 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
* @enable and @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 @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 @enable should
* be used.
*/
void (*commit)(struct drm_crtc *crtc);
/**
* @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
* ->mode_fixup() functions. If the CRTC cannot support the requested
* conversion from mode to adjusted_mode it should reject the modeset.
*
* 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.
*
* Also beware that neither core nor helpers filter modes before
* passing them to the driver: While the list of modes that is
* advertised to userspace is filtered using the connector's
* ->mode_valid() callback, neither the core nor the helpers do any
* filtering on modes passed in from userspace when setting a mode. It
* is therefore possible for userspace to pass in a mode that was
* previously filtered out using ->mode_valid() or add a custom mode
* that wasn't probed from EDID or similar to begin with. Even though
* this is an advanced feature and rarely used nowadays, some users rely
* on being able to specify modes manually so drivers must be prepared
* to deal with it. Specifically this means that all drivers need not
* only validate modes in ->mode_valid() but also in ->mode_fixup() to
* make sure invalid modes passed in from userspace are rejected.
*
* 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. It is
* also used by the transitional plane helpers to implement a
* @mode_set hook in drm_helper_crtc_mode_set().
*
* 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 @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);
/**
* @load_lut:
*
* Load a LUT prepared with the @gamma_set functions from
* &drm_fb_helper_funcs.
*
* This callback is optional and is only used by the fbdev emulation
* helpers.
*
* FIXME:
*
* This callback is functionally redundant with the core gamma table
* support and simply exists because the fbdev hasn't yet been
* refactored to use the core gamma table interfaces.
*/
void (*load_lut)(struct drm_crtc *crtc);
/**
* @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 ->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 @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);
/**
* @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 ->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 @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
* @enable must be the inverse of @disable for atomic drivers.
*/
void (*enable)(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() CRTCs' ->atomic_check()
* hooks are called after the ones for planes, which allows drivers to
* assign shared resources requested by planes in the CRTC 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&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 and by the
* transitional plane 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.
*
* 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_crtc_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 and by the
* transitional plane helpers, but it is optional.
*/
void (*atomic_begin)(struct drm_crtc *crtc,
struct drm_crtc_state *old_crtc_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 and by the
* transitional plane helpers, but it is optional.
*/
void (*atomic_flush)(struct drm_crtc *crtc,
struct drm_crtc_state *old_crtc_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 ->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.
*
* Comparing to @disable, this one provides the additional input
* parameter @old_crtc_state which could be used to access the old
* state. Atomic drivers should consider to use this one instead
* of @disable.
*/
void (*atomic_disable)(struct drm_crtc *crtc,
struct drm_crtc_state *old_crtc_state);
};
/**
* 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, the transitional plane
* 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_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.
*
* 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.
*
* Also beware that neither core nor helpers filter modes before
* passing them to the driver: While the list of modes that is
* advertised to userspace is filtered using the connector's
* ->mode_valid() callback, neither the core nor the helpers do any
* filtering on modes passed in from userspace when setting a mode. It
* is therefore possible for userspace to pass in a mode that was
* previously filtered out using ->mode_valid() or add a custom mode
* that wasn't probed from EDID or similar to begin with. Even though
* this is an advanced feature and rarely used nowadays, some users rely
* on being able to specify modes manually so drivers must be prepared
* to deal with it. Specifically this means that all drivers need not
* only validate modes in ->mode_valid() but also in ->mode_fixup() to
* make sure invalid modes passed in from userspace are rejected.
*
* 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);
/**
* @get_crtc:
*
* This callback is used by the legacy CRTC helpers to work around
* deficiencies in its own book-keeping.
*
* Do not use, use atomic helpers instead, which get the book keeping
* right.
*
* FIXME:
*
* Currently only nouveau is using this, and as soon as nouveau is
* atomic we can ditch this hook.
*/
struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder);
/**
* @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);
/**
* @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 the CRTC's own ->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.
*
* 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
* the CRTC's own ->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 used only by atomic helpers, for symmetry with @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.
*
* 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.
*
* 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 connector->probed_modes list. It should also update the
* EDID property by calling drm_mode_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 driver 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 @display_info, @width_mm and @height_mm fields of the
* struct &drm_connector are filled in.
*
* 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().
*
* Finally drivers that support audio probably want to update the ELD
* data, too, using drm_edid_to_eld().
*
* 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().
*
* RETURNS:
*
* The number of modes added by calling drm_mode_probed_add().
*/
int (*get_modes)(struct drm_connector *connector);
/**
* @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().
*
* NOTE:
*
* This only filters the mode list supplied to userspace in the
* GETCONNECOTR IOCTL. Userspace is free to create modes of its own and
* ask the kernel to use them. It this case the atomic helpers or legacy
* CRTC helpers will not call this function. Drivers therefore must
* still fully validate any mode passed in in a modeset request.
*
* RETURNS:
*
* Either 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);
/**
* @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 and you are using the atomic helpers.
* In this case, the core will call drm_atomic_helper_best_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_atomic_helper_best_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 free-standing
* state objects passed-in or assembled in the overall &drm_atomic_state
* update tracking structure.
*
* 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_connector_state *connector_state);
};
/**
* 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 and by the transitional plane
* helpers.
*/
struct drm_plane_helper_funcs {
/**
* @prepare_fb:
*
* This hook is to prepare a framebuffer for scanout by e.g. pinning
* it's 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 fence member 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.
*
* 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 and by the
* transitional plane helpers, but it is optional.
*
* RETURNS:
*
* 0 on success or one of the following negative error codes allowed by
* the atomic_commit hook in &drm_mode_config_funcs. 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 and by the
* transitional plane helpers, but it is optional.
*/
void (*cleanup_fb)(struct drm_plane *plane,
struct drm_plane_state *old_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&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 and by the
* transitional plane 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.
*
* 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_plane_state *state);
/**
* @atomic_update:
*
* Drivers should use this function to update the plane state. This
* hook is called in-between the ->atomic_begin() and
* ->atomic_flush() of &drm_crtc_helper_funcs.
*
* 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 and by the
* transitional plane helpers, but it is optional.
*/
void (*atomic_update)(struct drm_plane *plane,
struct drm_plane_state *old_state);
/**
* @atomic_disable:
*
* Drivers should use this function to unconditionally disable a plane.
* This hook is called in-between the ->atomic_begin() and
* ->atomic_flush() of &drm_crtc_helper_funcs. 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
* ->disable() hook in &drm_crtc_helper_funcs.
*
* 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 and by the
* transitional plane helpers, but it is optional.
*/
void (*atomic_disable)(struct drm_plane *plane,
struct drm_plane_state *old_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 preceeding 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 upate
* to be executed by the hardware, for example using
* drm_atomic_helper_wait_for_vblanks(), 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);
};
#endif