v4.19.13 snapshot.
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
new file mode 100644
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--- /dev/null
+++ b/include/drm/drm_crtc.h
@@ -0,0 +1,1141 @@
+/*
+ * Copyright © 2006 Keith Packard
+ * Copyright © 2007-2008 Dave Airlie
+ * Copyright © 2007-2008 Intel Corporation
+ *   Jesse Barnes <jesse.barnes@intel.com>
+ *
+ * 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_CRTC_H__
+#define __DRM_CRTC_H__
+
+#include <linux/i2c.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/fb.h>
+#include <linux/hdmi.h>
+#include <linux/media-bus-format.h>
+#include <uapi/drm/drm_mode.h>
+#include <uapi/drm/drm_fourcc.h>
+#include <drm/drm_modeset_lock.h>
+#include <drm/drm_rect.h>
+#include <drm/drm_mode_object.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_connector.h>
+#include <drm/drm_property.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_plane.h>
+#include <drm/drm_blend.h>
+#include <drm/drm_color_mgmt.h>
+#include <drm/drm_debugfs_crc.h>
+#include <drm/drm_mode_config.h>
+
+struct drm_device;
+struct drm_mode_set;
+struct drm_file;
+struct drm_clip_rect;
+struct drm_printer;
+struct device_node;
+struct dma_fence;
+struct edid;
+
+static inline int64_t U642I64(uint64_t val)
+{
+	return (int64_t)*((int64_t *)&val);
+}
+static inline uint64_t I642U64(int64_t val)
+{
+	return (uint64_t)*((uint64_t *)&val);
+}
+
+struct drm_crtc;
+struct drm_pending_vblank_event;
+struct drm_plane;
+struct drm_bridge;
+struct drm_atomic_state;
+
+struct drm_crtc_helper_funcs;
+struct drm_plane_helper_funcs;
+
+/**
+ * struct drm_crtc_state - mutable CRTC state
+ *
+ * Note that the distinction between @enable and @active is rather subtile:
+ * Flipping @active while @enable is set without changing anything else may
+ * never return in a failure from the &drm_mode_config_funcs.atomic_check
+ * callback. Userspace assumes that a DPMS On will always succeed. In other
+ * words: @enable controls resource assignment, @active controls the actual
+ * hardware state.
+ *
+ * The three booleans active_changed, connectors_changed and mode_changed are
+ * intended to indicate whether a full modeset is needed, rather than strictly
+ * describing what has changed in a commit. See also:
+ * drm_atomic_crtc_needs_modeset()
+ *
+ * WARNING: Transitional helpers (like drm_helper_crtc_mode_set() or
+ * drm_helper_crtc_mode_set_base()) do not maintain many of the derived control
+ * state like @plane_mask so drivers not converted over to atomic helpers should
+ * not rely on these being accurate!
+ */
+struct drm_crtc_state {
+	/** @crtc: backpointer to the CRTC */
+	struct drm_crtc *crtc;
+
+	/**
+	 * @enable: Whether the CRTC should be enabled, gates all other state.
+	 * This controls reservations of shared resources. Actual hardware state
+	 * is controlled by @active.
+	 */
+	bool enable;
+
+	/**
+	 * @active: Whether the CRTC is actively displaying (used for DPMS).
+	 * Implies that @enable is set. The driver must not release any shared
+	 * resources if @active is set to false but @enable still true, because
+	 * userspace expects that a DPMS ON always succeeds.
+	 *
+	 * Hence drivers must not consult @active in their various
+	 * &drm_mode_config_funcs.atomic_check callback to reject an atomic
+	 * commit. They can consult it to aid in the computation of derived
+	 * hardware state, since even in the DPMS OFF state the display hardware
+	 * should be as much powered down as when the CRTC is completely
+	 * disabled through setting @enable to false.
+	 */
+	bool active;
+
+	/**
+	 * @planes_changed: Planes on this crtc are updated. Used by the atomic
+	 * helpers and drivers to steer the atomic commit control flow.
+	 */
+	bool planes_changed : 1;
+
+	/**
+	 * @mode_changed: @mode or @enable has been changed. Used by the atomic
+	 * helpers and drivers to steer the atomic commit control flow. See also
+	 * drm_atomic_crtc_needs_modeset().
+	 *
+	 * Drivers are supposed to set this for any CRTC state changes that
+	 * require a full modeset. They can also reset it to false if e.g. a
+	 * @mode change can be done without a full modeset by only changing
+	 * scaler settings.
+	 */
+	bool mode_changed : 1;
+
+	/**
+	 * @active_changed: @active has been toggled. Used by the atomic
+	 * helpers and drivers to steer the atomic commit control flow. See also
+	 * drm_atomic_crtc_needs_modeset().
+	 */
+	bool active_changed : 1;
+
+	/**
+	 * @connectors_changed: Connectors to this crtc have been updated,
+	 * either in their state or routing. Used by the atomic
+	 * helpers and drivers to steer the atomic commit control flow. See also
+	 * drm_atomic_crtc_needs_modeset().
+	 *
+	 * Drivers are supposed to set this as-needed from their own atomic
+	 * check code, e.g. from &drm_encoder_helper_funcs.atomic_check
+	 */
+	bool connectors_changed : 1;
+	/**
+	 * @zpos_changed: zpos values of planes on this crtc have been updated.
+	 * Used by the atomic helpers and drivers to steer the atomic commit
+	 * control flow.
+	 */
+	bool zpos_changed : 1;
+	/**
+	 * @color_mgmt_changed: Color management properties have changed
+	 * (@gamma_lut, @degamma_lut or @ctm). Used by the atomic helpers and
+	 * drivers to steer the atomic commit control flow.
+	 */
+	bool color_mgmt_changed : 1;
+
+	/**
+	 * @no_vblank:
+	 *
+	 * Reflects the ability of a CRTC to send VBLANK events. This state
+	 * usually depends on the pipeline configuration, and the main usuage
+	 * is CRTCs feeding a writeback connector operating in oneshot mode.
+	 * In this case the VBLANK event is only generated when a job is queued
+	 * to the writeback connector, and we want the core to fake VBLANK
+	 * events when this part of the pipeline hasn't changed but others had
+	 * or when the CRTC and connectors are being disabled.
+	 *
+	 * __drm_atomic_helper_crtc_duplicate_state() will not reset the value
+	 * from the current state, the CRTC driver is then responsible for
+	 * updating this field when needed.
+	 *
+	 * Note that the combination of &drm_crtc_state.event == NULL and
+	 * &drm_crtc_state.no_blank == true is valid and usually used when the
+	 * writeback connector attached to the CRTC has a new job queued. In
+	 * this case the driver will send the VBLANK event on its own when the
+	 * writeback job is complete.
+	 */
+	bool no_vblank : 1;
+
+	/**
+	 * @plane_mask: Bitmask of drm_plane_mask(plane) of planes attached to
+	 * this CRTC.
+	 */
+	u32 plane_mask;
+
+	/**
+	 * @connector_mask: Bitmask of drm_connector_mask(connector) of
+	 * connectors attached to this CRTC.
+	 */
+	u32 connector_mask;
+
+	/**
+	 * @encoder_mask: Bitmask of drm_encoder_mask(encoder) of encoders
+	 * attached to this CRTC.
+	 */
+	u32 encoder_mask;
+
+	/**
+	 * @adjusted_mode:
+	 *
+	 * Internal display timings which can be used by the driver to handle
+	 * differences between the mode requested by userspace in @mode and what
+	 * is actually programmed into the hardware.
+	 *
+	 * For drivers using &drm_bridge, this stores hardware display timings
+	 * used between the CRTC and the first bridge. For other drivers, the
+	 * meaning of the adjusted_mode field is purely driver implementation
+	 * defined information, and will usually be used to store the hardware
+	 * display timings used between the CRTC and encoder blocks.
+	 */
+	struct drm_display_mode adjusted_mode;
+
+	/**
+	 * @mode:
+	 *
+	 * Display timings requested by userspace. The driver should try to
+	 * match the refresh rate as close as possible (but note that it's
+	 * undefined what exactly is close enough, e.g. some of the HDMI modes
+	 * only differ in less than 1% of the refresh rate). The active width
+	 * and height as observed by userspace for positioning planes must match
+	 * exactly.
+	 *
+	 * For external connectors where the sink isn't fixed (like with a
+	 * built-in panel), this mode here should match the physical mode on the
+	 * wire to the last details (i.e. including sync polarities and
+	 * everything).
+	 */
+	struct drm_display_mode mode;
+
+	/**
+	 * @mode_blob: &drm_property_blob for @mode, for exposing the mode to
+	 * atomic userspace.
+	 */
+	struct drm_property_blob *mode_blob;
+
+	/**
+	 * @degamma_lut:
+	 *
+	 * Lookup table for converting framebuffer pixel data before apply the
+	 * color conversion matrix @ctm. See drm_crtc_enable_color_mgmt(). The
+	 * blob (if not NULL) is an array of &struct drm_color_lut.
+	 */
+	struct drm_property_blob *degamma_lut;
+
+	/**
+	 * @ctm:
+	 *
+	 * Color transformation matrix. See drm_crtc_enable_color_mgmt(). The
+	 * blob (if not NULL) is a &struct drm_color_ctm.
+	 */
+	struct drm_property_blob *ctm;
+
+	/**
+	 * @gamma_lut:
+	 *
+	 * Lookup table for converting pixel data after the color conversion
+	 * matrix @ctm.  See drm_crtc_enable_color_mgmt(). The blob (if not
+	 * NULL) is an array of &struct drm_color_lut.
+	 */
+	struct drm_property_blob *gamma_lut;
+
+	/**
+	 * @target_vblank:
+	 *
+	 * Target vertical blank period when a page flip
+	 * should take effect.
+	 */
+	u32 target_vblank;
+
+	/**
+	 * @pageflip_flags:
+	 *
+	 * DRM_MODE_PAGE_FLIP_* flags, as passed to the page flip ioctl.
+	 * Zero in any other case.
+	 */
+	u32 pageflip_flags;
+
+	/**
+	 * @event:
+	 *
+	 * Optional pointer to a DRM event to signal upon completion of the
+	 * state update. The driver must send out the event when the atomic
+	 * commit operation completes. There are two cases:
+	 *
+	 *  - The event is for a CRTC which is being disabled through this
+	 *    atomic commit. In that case the event can be send out any time
+	 *    after the hardware has stopped scanning out the current
+	 *    framebuffers. It should contain the timestamp and counter for the
+	 *    last vblank before the display pipeline was shut off. The simplest
+	 *    way to achieve that is calling drm_crtc_send_vblank_event()
+	 *    somewhen after drm_crtc_vblank_off() has been called.
+	 *
+	 *  - For a CRTC which is enabled at the end of the commit (even when it
+	 *    undergoes an full modeset) the vblank timestamp and counter must
+	 *    be for the vblank right before the first frame that scans out the
+	 *    new set of buffers. Again the event can only be sent out after the
+	 *    hardware has stopped scanning out the old buffers.
+	 *
+	 *  - Events for disabled CRTCs are not allowed, and drivers can ignore
+	 *    that case.
+	 *
+	 * This can be handled by the drm_crtc_send_vblank_event() function,
+	 * which the driver should call on the provided event upon completion of
+	 * the atomic commit. Note that if the driver supports vblank signalling
+	 * and timestamping the vblank counters and timestamps must agree with
+	 * the ones returned from page flip events. With the current vblank
+	 * helper infrastructure this can be achieved by holding a vblank
+	 * reference while the page flip is pending, acquired through
+	 * drm_crtc_vblank_get() and released with drm_crtc_vblank_put().
+	 * Drivers are free to implement their own vblank counter and timestamp
+	 * tracking though, e.g. if they have accurate timestamp registers in
+	 * hardware.
+	 *
+	 * For hardware which supports some means to synchronize vblank
+	 * interrupt delivery with committing display state there's also
+	 * drm_crtc_arm_vblank_event(). See the documentation of that function
+	 * for a detailed discussion of the constraints it needs to be used
+	 * safely.
+	 *
+	 * If the device can't notify of flip completion in a race-free way
+	 * at all, then the event should be armed just after the page flip is
+	 * committed. In the worst case the driver will send the event to
+	 * userspace one frame too late. This doesn't allow for a real atomic
+	 * update, but it should avoid tearing.
+	 */
+	struct drm_pending_vblank_event *event;
+
+	/**
+	 * @commit:
+	 *
+	 * This tracks how the commit for this update proceeds through the
+	 * various phases. This is never cleared, except when we destroy the
+	 * state, so that subsequent commits can synchronize with previous ones.
+	 */
+	struct drm_crtc_commit *commit;
+
+	/** @state: backpointer to global drm_atomic_state */
+	struct drm_atomic_state *state;
+};
+
+/**
+ * struct drm_crtc_funcs - control CRTCs for a given device
+ *
+ * The drm_crtc_funcs structure is the central CRTC management structure
+ * in the DRM.  Each CRTC controls one or more connectors (note that the name
+ * CRTC is simply historical, a CRTC may control LVDS, VGA, DVI, TV out, etc.
+ * connectors, not just CRTs).
+ *
+ * Each driver is responsible for filling out this structure at startup time,
+ * in addition to providing other modesetting features, like i2c and DDC
+ * bus accessors.
+ */
+struct drm_crtc_funcs {
+	/**
+	 * @reset:
+	 *
+	 * Reset CRTC hardware and software state to off. This function isn't
+	 * called by the core directly, only through drm_mode_config_reset().
+	 * It's not a helper hook only for historical reasons.
+	 *
+	 * Atomic drivers can use drm_atomic_helper_crtc_reset() to reset
+	 * atomic state using this hook.
+	 */
+	void (*reset)(struct drm_crtc *crtc);
+
+	/**
+	 * @cursor_set:
+	 *
+	 * Update the cursor image. The cursor position is relative to the CRTC
+	 * and can be partially or fully outside of the visible area.
+	 *
+	 * Note that contrary to all other KMS functions the legacy cursor entry
+	 * points don't take a framebuffer object, but instead take directly a
+	 * raw buffer object id from the driver's buffer manager (which is
+	 * either GEM or TTM for current drivers).
+	 *
+	 * This entry point is deprecated, drivers should instead implement
+	 * universal plane support and register a proper cursor plane using
+	 * drm_crtc_init_with_planes().
+	 *
+	 * This callback is optional
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*cursor_set)(struct drm_crtc *crtc, struct drm_file *file_priv,
+			  uint32_t handle, uint32_t width, uint32_t height);
+
+	/**
+	 * @cursor_set2:
+	 *
+	 * Update the cursor image, including hotspot information. The hotspot
+	 * must not affect the cursor position in CRTC coordinates, but is only
+	 * meant as a hint for virtualized display hardware to coordinate the
+	 * guests and hosts cursor position. The cursor hotspot is relative to
+	 * the cursor image. Otherwise this works exactly like @cursor_set.
+	 *
+	 * This entry point is deprecated, drivers should instead implement
+	 * universal plane support and register a proper cursor plane using
+	 * drm_crtc_init_with_planes().
+	 *
+	 * This callback is optional.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*cursor_set2)(struct drm_crtc *crtc, struct drm_file *file_priv,
+			   uint32_t handle, uint32_t width, uint32_t height,
+			   int32_t hot_x, int32_t hot_y);
+
+	/**
+	 * @cursor_move:
+	 *
+	 * Update the cursor position. The cursor does not need to be visible
+	 * when this hook is called.
+	 *
+	 * This entry point is deprecated, drivers should instead implement
+	 * universal plane support and register a proper cursor plane using
+	 * drm_crtc_init_with_planes().
+	 *
+	 * This callback is optional.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*cursor_move)(struct drm_crtc *crtc, int x, int y);
+
+	/**
+	 * @gamma_set:
+	 *
+	 * Set gamma on the CRTC.
+	 *
+	 * This callback is optional.
+	 *
+	 * Atomic drivers who want to support gamma tables should implement the
+	 * atomic color management support, enabled by calling
+	 * drm_crtc_enable_color_mgmt(), which then supports the legacy gamma
+	 * interface through the drm_atomic_helper_legacy_gamma_set()
+	 * compatibility implementation.
+	 */
+	int (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
+			 uint32_t size,
+			 struct drm_modeset_acquire_ctx *ctx);
+
+	/**
+	 * @destroy:
+	 *
+	 * Clean up plane resources. This is only called at driver unload time
+	 * through drm_mode_config_cleanup() since a CRTC cannot be hotplugged
+	 * in DRM.
+	 */
+	void (*destroy)(struct drm_crtc *crtc);
+
+	/**
+	 * @set_config:
+	 *
+	 * This is the main legacy entry point to change the modeset state on a
+	 * CRTC. All the details of the desired configuration are passed in a
+	 * &struct drm_mode_set - see there for details.
+	 *
+	 * Drivers implementing atomic modeset should use
+	 * drm_atomic_helper_set_config() to implement this hook.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*set_config)(struct drm_mode_set *set,
+			  struct drm_modeset_acquire_ctx *ctx);
+
+	/**
+	 * @page_flip:
+	 *
+	 * Legacy entry point to schedule a flip to the given framebuffer.
+	 *
+	 * Page flipping is a synchronization mechanism that replaces the frame
+	 * buffer being scanned out by the CRTC with a new frame buffer during
+	 * vertical blanking, avoiding tearing (except when requested otherwise
+	 * through the DRM_MODE_PAGE_FLIP_ASYNC flag). When an application
+	 * requests a page flip the DRM core verifies that the new frame buffer
+	 * is large enough to be scanned out by the CRTC in the currently
+	 * configured mode and then calls this hook with a pointer to the new
+	 * frame buffer.
+	 *
+	 * The driver must wait for any pending rendering to the new framebuffer
+	 * to complete before executing the flip. It should also wait for any
+	 * pending rendering from other drivers if the underlying buffer is a
+	 * shared dma-buf.
+	 *
+	 * An application can request to be notified when the page flip has
+	 * completed. The drm core will supply a &struct drm_event in the event
+	 * parameter in this case. This can be handled by the
+	 * drm_crtc_send_vblank_event() function, which the driver should call on
+	 * the provided event upon completion of the flip. Note that if
+	 * the driver supports vblank signalling and timestamping the vblank
+	 * counters and timestamps must agree with the ones returned from page
+	 * flip events. With the current vblank helper infrastructure this can
+	 * be achieved by holding a vblank reference while the page flip is
+	 * pending, acquired through drm_crtc_vblank_get() and released with
+	 * drm_crtc_vblank_put(). Drivers are free to implement their own vblank
+	 * counter and timestamp tracking though, e.g. if they have accurate
+	 * timestamp registers in hardware.
+	 *
+	 * This callback is optional.
+	 *
+	 * NOTE:
+	 *
+	 * Very early versions of the KMS ABI mandated that the driver must
+	 * block (but not reject) any rendering to the old framebuffer until the
+	 * flip operation has completed and the old framebuffer is no longer
+	 * visible. This requirement has been lifted, and userspace is instead
+	 * expected to request delivery of an event and wait with recycling old
+	 * buffers until such has been received.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure. Note that if a
+	 * page flip operation is already pending the callback should return
+	 * -EBUSY. Pageflips on a disabled CRTC (either by setting a NULL mode
+	 * or just runtime disabled through DPMS respectively the new atomic
+	 * "ACTIVE" state) should result in an -EINVAL error code. Note that
+	 * drm_atomic_helper_page_flip() checks this already for atomic drivers.
+	 */
+	int (*page_flip)(struct drm_crtc *crtc,
+			 struct drm_framebuffer *fb,
+			 struct drm_pending_vblank_event *event,
+			 uint32_t flags,
+			 struct drm_modeset_acquire_ctx *ctx);
+
+	/**
+	 * @page_flip_target:
+	 *
+	 * Same as @page_flip but with an additional parameter specifying the
+	 * absolute target vertical blank period (as reported by
+	 * drm_crtc_vblank_count()) when the flip should take effect.
+	 *
+	 * Note that the core code calls drm_crtc_vblank_get before this entry
+	 * point, and will call drm_crtc_vblank_put if this entry point returns
+	 * any non-0 error code. It's the driver's responsibility to call
+	 * drm_crtc_vblank_put after this entry point returns 0, typically when
+	 * the flip completes.
+	 */
+	int (*page_flip_target)(struct drm_crtc *crtc,
+				struct drm_framebuffer *fb,
+				struct drm_pending_vblank_event *event,
+				uint32_t flags, uint32_t target,
+				struct drm_modeset_acquire_ctx *ctx);
+
+	/**
+	 * @set_property:
+	 *
+	 * This is the legacy entry point to update a property attached to the
+	 * CRTC.
+	 *
+	 * This callback is optional if the driver does not support any legacy
+	 * driver-private properties. For atomic drivers it is not used because
+	 * property handling is done entirely in the DRM core.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*set_property)(struct drm_crtc *crtc,
+			    struct drm_property *property, uint64_t val);
+
+	/**
+	 * @atomic_duplicate_state:
+	 *
+	 * Duplicate the current atomic state for this CRTC and return it.
+	 * The core and helpers guarantee that any atomic state duplicated with
+	 * this hook and still owned by the caller (i.e. not transferred to the
+	 * driver by calling &drm_mode_config_funcs.atomic_commit) will be
+	 * cleaned up by calling the @atomic_destroy_state hook in this
+	 * structure.
+	 *
+	 * This callback is mandatory for atomic drivers.
+	 *
+	 * Atomic drivers which don't subclass &struct drm_crtc_state should use
+	 * drm_atomic_helper_crtc_duplicate_state(). Drivers that subclass the
+	 * state structure to extend it with driver-private state should use
+	 * __drm_atomic_helper_crtc_duplicate_state() to make sure shared state is
+	 * duplicated in a consistent fashion across drivers.
+	 *
+	 * It is an error to call this hook before &drm_crtc.state has been
+	 * initialized correctly.
+	 *
+	 * NOTE:
+	 *
+	 * If the duplicate state references refcounted resources this hook must
+	 * acquire a reference for each of them. The driver must release these
+	 * references again in @atomic_destroy_state.
+	 *
+	 * RETURNS:
+	 *
+	 * Duplicated atomic state or NULL when the allocation failed.
+	 */
+	struct drm_crtc_state *(*atomic_duplicate_state)(struct drm_crtc *crtc);
+
+	/**
+	 * @atomic_destroy_state:
+	 *
+	 * Destroy a state duplicated with @atomic_duplicate_state and release
+	 * or unreference all resources it references
+	 *
+	 * This callback is mandatory for atomic drivers.
+	 */
+	void (*atomic_destroy_state)(struct drm_crtc *crtc,
+				     struct drm_crtc_state *state);
+
+	/**
+	 * @atomic_set_property:
+	 *
+	 * Decode a driver-private property value and store the decoded value
+	 * into the passed-in state structure. Since the atomic core decodes all
+	 * standardized properties (even for extensions beyond the core set of
+	 * properties which might not be implemented by all drivers) this
+	 * requires drivers to subclass the state structure.
+	 *
+	 * Such driver-private properties should really only be implemented for
+	 * truly hardware/vendor specific state. Instead it is preferred to
+	 * standardize atomic extension and decode the properties used to expose
+	 * such an extension in the core.
+	 *
+	 * Do not call this function directly, use
+	 * drm_atomic_crtc_set_property() instead.
+	 *
+	 * This callback is optional if the driver does not support any
+	 * driver-private atomic properties.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the state assembly 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). Drivers MUST NOT touch any persistent state (hardware or
+	 * software) or data structures except the passed in @state parameter.
+	 *
+	 * Also since userspace controls in which order properties are set this
+	 * function must not do any input validation (since the state update is
+	 * incomplete and hence likely inconsistent). Instead any such input
+	 * validation must be done in the various atomic_check callbacks.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 if the property has been found, -EINVAL if the property isn't
+	 * implemented by the driver (which should never happen, the core only
+	 * asks for properties attached to this CRTC). No other validation is
+	 * allowed by the driver. The core already checks that the property
+	 * value is within the range (integer, valid enum value, ...) the driver
+	 * set when registering the property.
+	 */
+	int (*atomic_set_property)(struct drm_crtc *crtc,
+				   struct drm_crtc_state *state,
+				   struct drm_property *property,
+				   uint64_t val);
+	/**
+	 * @atomic_get_property:
+	 *
+	 * Reads out the decoded driver-private property. This is used to
+	 * implement the GETCRTC IOCTL.
+	 *
+	 * Do not call this function directly, use
+	 * drm_atomic_crtc_get_property() instead.
+	 *
+	 * This callback is optional if the driver does not support any
+	 * driver-private atomic properties.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success, -EINVAL if the property isn't implemented by the
+	 * driver (which should never happen, the core only asks for
+	 * properties attached to this CRTC).
+	 */
+	int (*atomic_get_property)(struct drm_crtc *crtc,
+				   const struct drm_crtc_state *state,
+				   struct drm_property *property,
+				   uint64_t *val);
+
+	/**
+	 * @late_register:
+	 *
+	 * This optional hook can be used to register additional userspace
+	 * interfaces attached to the crtc like debugfs interfaces.
+	 * It is called late in the driver load sequence from drm_dev_register().
+	 * Everything added from this callback should be unregistered in
+	 * the early_unregister callback.
+	 *
+	 * Returns:
+	 *
+	 * 0 on success, or a negative error code on failure.
+	 */
+	int (*late_register)(struct drm_crtc *crtc);
+
+	/**
+	 * @early_unregister:
+	 *
+	 * This optional hook should be used to unregister the additional
+	 * userspace interfaces attached to the crtc from
+	 * @late_register. It is called from drm_dev_unregister(),
+	 * early in the driver unload sequence to disable userspace access
+	 * before data structures are torndown.
+	 */
+	void (*early_unregister)(struct drm_crtc *crtc);
+
+	/**
+	 * @set_crc_source:
+	 *
+	 * Changes the source of CRC checksums of frames at the request of
+	 * userspace, typically for testing purposes. The sources available are
+	 * specific of each driver and a %NULL value indicates that CRC
+	 * generation is to be switched off.
+	 *
+	 * When CRC generation is enabled, the driver should call
+	 * drm_crtc_add_crc_entry() at each frame, providing any information
+	 * that characterizes the frame contents in the crcN arguments, as
+	 * provided from the configured source. Drivers must accept an "auto"
+	 * source name that will select a default source for this CRTC.
+	 *
+	 * Note that "auto" can depend upon the current modeset configuration,
+	 * e.g. it could pick an encoder or output specific CRC sampling point.
+	 *
+	 * This callback is optional if the driver does not support any CRC
+	 * generation functionality.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*set_crc_source)(struct drm_crtc *crtc, const char *source,
+			      size_t *values_cnt);
+
+	/**
+	 * @atomic_print_state:
+	 *
+	 * If driver subclasses &struct drm_crtc_state, it should implement
+	 * this optional hook for printing additional driver specific state.
+	 *
+	 * Do not call this directly, use drm_atomic_crtc_print_state()
+	 * instead.
+	 */
+	void (*atomic_print_state)(struct drm_printer *p,
+				   const struct drm_crtc_state *state);
+
+	/**
+	 * @get_vblank_counter:
+	 *
+	 * Driver callback for fetching a raw hardware vblank counter for the
+	 * CRTC. It's meant to be used by new drivers as the replacement of
+	 * &drm_driver.get_vblank_counter hook.
+	 *
+	 * This callback is optional. If a device doesn't have a hardware
+	 * counter, the driver can simply leave the hook as NULL. The DRM core
+	 * will account for missed vblank events while interrupts where disabled
+	 * based on system timestamps.
+	 *
+	 * Wraparound handling and loss of events due to modesetting is dealt
+	 * with in the DRM core code, as long as drivers call
+	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
+	 * enabling a CRTC.
+	 *
+	 * See also &drm_device.vblank_disable_immediate and
+	 * &drm_device.max_vblank_count.
+	 *
+	 * Returns:
+	 *
+	 * Raw vblank counter value.
+	 */
+	u32 (*get_vblank_counter)(struct drm_crtc *crtc);
+
+	/**
+	 * @enable_vblank:
+	 *
+	 * Enable vblank interrupts for the CRTC. It's meant to be used by
+	 * new drivers as the replacement of &drm_driver.enable_vblank hook.
+	 *
+	 * Returns:
+	 *
+	 * Zero on success, appropriate errno if the vblank interrupt cannot
+	 * be enabled.
+	 */
+	int (*enable_vblank)(struct drm_crtc *crtc);
+
+	/**
+	 * @disable_vblank:
+	 *
+	 * Disable vblank interrupts for the CRTC. It's meant to be used by
+	 * new drivers as the replacement of &drm_driver.disable_vblank hook.
+	 */
+	void (*disable_vblank)(struct drm_crtc *crtc);
+};
+
+/**
+ * struct drm_crtc - central CRTC control structure
+ *
+ * Each CRTC may have one or more connectors associated with it.  This structure
+ * allows the CRTC to be controlled.
+ */
+struct drm_crtc {
+	/** @dev: parent DRM device */
+	struct drm_device *dev;
+	/** @port: OF node used by drm_of_find_possible_crtcs(). */
+	struct device_node *port;
+	/**
+	 * @head:
+	 *
+	 * List of all CRTCs on @dev, linked from &drm_mode_config.crtc_list.
+	 * Invariant over the lifetime of @dev and therefore does not need
+	 * locking.
+	 */
+	struct list_head head;
+
+	/** @name: human readable name, can be overwritten by the driver */
+	char *name;
+
+	/**
+	 * @mutex:
+	 *
+	 * This provides a read lock for the overall CRTC state (mode, dpms
+	 * state, ...) and a write lock for everything which can be update
+	 * without a full modeset (fb, cursor data, CRTC properties ...). A full
+	 * modeset also need to grab &drm_mode_config.connection_mutex.
+	 *
+	 * For atomic drivers specifically this protects @state.
+	 */
+	struct drm_modeset_lock mutex;
+
+	/** @base: base KMS object for ID tracking etc. */
+	struct drm_mode_object base;
+
+	/**
+	 * @primary:
+	 * Primary plane for this CRTC. Note that this is only
+	 * relevant for legacy IOCTL, it specifies the plane implicitly used by
+	 * the SETCRTC and PAGE_FLIP IOCTLs. It does not have any significance
+	 * beyond that.
+	 */
+	struct drm_plane *primary;
+
+	/**
+	 * @cursor:
+	 * Cursor plane for this CRTC. Note that this is only relevant for
+	 * legacy IOCTL, it specifies the plane implicitly used by the SETCURSOR
+	 * and SETCURSOR2 IOCTLs. It does not have any significance
+	 * beyond that.
+	 */
+	struct drm_plane *cursor;
+
+	/**
+	 * @index: Position inside the mode_config.list, can be used as an array
+	 * index. It is invariant over the lifetime of the CRTC.
+	 */
+	unsigned index;
+
+	/**
+	 * @cursor_x: Current x position of the cursor, used for universal
+	 * cursor planes because the SETCURSOR IOCTL only can update the
+	 * framebuffer without supplying the coordinates. Drivers should not use
+	 * this directly, atomic drivers should look at &drm_plane_state.crtc_x
+	 * of the cursor plane instead.
+	 */
+	int cursor_x;
+	/**
+	 * @cursor_y: Current y position of the cursor, used for universal
+	 * cursor planes because the SETCURSOR IOCTL only can update the
+	 * framebuffer without supplying the coordinates. Drivers should not use
+	 * this directly, atomic drivers should look at &drm_plane_state.crtc_y
+	 * of the cursor plane instead.
+	 */
+	int cursor_y;
+
+	/**
+	 * @enabled:
+	 *
+	 * Is this CRTC enabled? Should only be used by legacy drivers, atomic
+	 * drivers should instead consult &drm_crtc_state.enable and
+	 * &drm_crtc_state.active. Atomic drivers can update this by calling
+	 * drm_atomic_helper_update_legacy_modeset_state().
+	 */
+	bool enabled;
+
+	/**
+	 * @mode:
+	 *
+	 * Current mode timings. Should only be used by legacy drivers, atomic
+	 * drivers should instead consult &drm_crtc_state.mode. Atomic drivers
+	 * can update this by calling
+	 * drm_atomic_helper_update_legacy_modeset_state().
+	 */
+	struct drm_display_mode mode;
+
+	/**
+	 * @hwmode:
+	 *
+	 * Programmed mode in hw, after adjustments for encoders, crtc, panel
+	 * scaling etc. Should only be used by legacy drivers, for high
+	 * precision vblank timestamps in
+	 * drm_calc_vbltimestamp_from_scanoutpos().
+	 *
+	 * Note that atomic drivers should not use this, but instead use
+	 * &drm_crtc_state.adjusted_mode. And for high-precision timestamps
+	 * drm_calc_vbltimestamp_from_scanoutpos() used &drm_vblank_crtc.hwmode,
+	 * which is filled out by calling drm_calc_timestamping_constants().
+	 */
+	struct drm_display_mode hwmode;
+
+	/**
+	 * @x:
+	 * x position on screen. Should only be used by legacy drivers, atomic
+	 * drivers should look at &drm_plane_state.crtc_x of the primary plane
+	 * instead. Updated by calling
+	 * drm_atomic_helper_update_legacy_modeset_state().
+	 */
+	int x;
+	/**
+	 * @y:
+	 * y position on screen. Should only be used by legacy drivers, atomic
+	 * drivers should look at &drm_plane_state.crtc_y of the primary plane
+	 * instead. Updated by calling
+	 * drm_atomic_helper_update_legacy_modeset_state().
+	 */
+	int y;
+
+	/** @funcs: CRTC control functions */
+	const struct drm_crtc_funcs *funcs;
+
+	/**
+	 * @gamma_size: Size of legacy gamma ramp reported to userspace. Set up
+	 * by calling drm_mode_crtc_set_gamma_size().
+	 */
+	uint32_t gamma_size;
+
+	/**
+	 * @gamma_store: Gamma ramp values used by the legacy SETGAMMA and
+	 * GETGAMMA IOCTls. Set up by calling drm_mode_crtc_set_gamma_size().
+	 */
+	uint16_t *gamma_store;
+
+	/** @helper_private: mid-layer private data */
+	const struct drm_crtc_helper_funcs *helper_private;
+
+	/** @properties: property tracking for this CRTC */
+	struct drm_object_properties properties;
+
+	/**
+	 * @state:
+	 *
+	 * Current atomic state for this CRTC.
+	 *
+	 * This is protected by @mutex. Note that nonblocking atomic commits
+	 * access the current CRTC state without taking locks. Either by going
+	 * through the &struct drm_atomic_state pointers, see
+	 * for_each_oldnew_crtc_in_state(), for_each_old_crtc_in_state() and
+	 * for_each_new_crtc_in_state(). Or through careful ordering of atomic
+	 * commit operations as implemented in the atomic helpers, see
+	 * &struct drm_crtc_commit.
+	 */
+	struct drm_crtc_state *state;
+
+	/**
+	 * @commit_list:
+	 *
+	 * List of &drm_crtc_commit structures tracking pending commits.
+	 * Protected by @commit_lock. This list holds its own full reference,
+	 * as does the ongoing commit.
+	 *
+	 * "Note that the commit for a state change is also tracked in
+	 * &drm_crtc_state.commit. For accessing the immediately preceding
+	 * commit in an atomic update it is recommended to just use that
+	 * pointer in the old CRTC state, since accessing that doesn't need
+	 * any locking or list-walking. @commit_list should only be used to
+	 * stall for framebuffer cleanup that's signalled through
+	 * &drm_crtc_commit.cleanup_done."
+	 */
+	struct list_head commit_list;
+
+	/**
+	 * @commit_lock:
+	 *
+	 * Spinlock to protect @commit_list.
+	 */
+	spinlock_t commit_lock;
+
+#ifdef CONFIG_DEBUG_FS
+	/**
+	 * @debugfs_entry:
+	 *
+	 * Debugfs directory for this CRTC.
+	 */
+	struct dentry *debugfs_entry;
+#endif
+
+	/**
+	 * @crc:
+	 *
+	 * Configuration settings of CRC capture.
+	 */
+	struct drm_crtc_crc crc;
+
+	/**
+	 * @fence_context:
+	 *
+	 * timeline context used for fence operations.
+	 */
+	unsigned int fence_context;
+
+	/**
+	 * @fence_lock:
+	 *
+	 * spinlock to protect the fences in the fence_context.
+	 */
+	spinlock_t fence_lock;
+	/**
+	 * @fence_seqno:
+	 *
+	 * Seqno variable used as monotonic counter for the fences
+	 * created on the CRTC's timeline.
+	 */
+	unsigned long fence_seqno;
+
+	/**
+	 * @timeline_name:
+	 *
+	 * The name of the CRTC's fence timeline.
+	 */
+	char timeline_name[32];
+};
+
+/**
+ * struct drm_mode_set - new values for a CRTC config change
+ * @fb: framebuffer to use for new config
+ * @crtc: CRTC whose configuration we're about to change
+ * @mode: mode timings to use
+ * @x: position of this CRTC relative to @fb
+ * @y: position of this CRTC relative to @fb
+ * @connectors: array of connectors to drive with this CRTC if possible
+ * @num_connectors: size of @connectors array
+ *
+ * This represents a modeset configuration for the legacy SETCRTC ioctl and is
+ * also used internally. Atomic drivers instead use &drm_atomic_state.
+ */
+struct drm_mode_set {
+	struct drm_framebuffer *fb;
+	struct drm_crtc *crtc;
+	struct drm_display_mode *mode;
+
+	uint32_t x;
+	uint32_t y;
+
+	struct drm_connector **connectors;
+	size_t num_connectors;
+};
+
+#define obj_to_crtc(x) container_of(x, struct drm_crtc, base)
+
+__printf(6, 7)
+int drm_crtc_init_with_planes(struct drm_device *dev,
+			      struct drm_crtc *crtc,
+			      struct drm_plane *primary,
+			      struct drm_plane *cursor,
+			      const struct drm_crtc_funcs *funcs,
+			      const char *name, ...);
+void drm_crtc_cleanup(struct drm_crtc *crtc);
+
+/**
+ * drm_crtc_index - find the index of a registered CRTC
+ * @crtc: CRTC to find index for
+ *
+ * Given a registered CRTC, return the index of that CRTC within a DRM
+ * device's list of CRTCs.
+ */
+static inline unsigned int drm_crtc_index(const struct drm_crtc *crtc)
+{
+	return crtc->index;
+}
+
+/**
+ * drm_crtc_mask - find the mask of a registered CRTC
+ * @crtc: CRTC to find mask for
+ *
+ * Given a registered CRTC, return the mask bit of that CRTC for the
+ * &drm_encoder.possible_crtcs and &drm_plane.possible_crtcs fields.
+ */
+static inline uint32_t drm_crtc_mask(const struct drm_crtc *crtc)
+{
+	return 1 << drm_crtc_index(crtc);
+}
+
+int drm_crtc_force_disable(struct drm_crtc *crtc);
+int drm_crtc_force_disable_all(struct drm_device *dev);
+
+int drm_mode_set_config_internal(struct drm_mode_set *set);
+struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx);
+
+/**
+ * drm_crtc_find - look up a CRTC object from its ID
+ * @dev: DRM device
+ * @file_priv: drm file to check for lease against.
+ * @id: &drm_mode_object ID
+ *
+ * This can be used to look up a CRTC from its userspace ID. Only used by
+ * drivers for legacy IOCTLs and interface, nowadays extensions to the KMS
+ * userspace interface should be done using &drm_property.
+ */
+static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
+		struct drm_file *file_priv,
+		uint32_t id)
+{
+	struct drm_mode_object *mo;
+	mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_CRTC);
+	return mo ? obj_to_crtc(mo) : NULL;
+}
+
+/**
+ * drm_for_each_crtc - iterate over all CRTCs
+ * @crtc: a &struct drm_crtc as the loop cursor
+ * @dev: the &struct drm_device
+ *
+ * Iterate over all CRTCs of @dev.
+ */
+#define drm_for_each_crtc(crtc, dev) \
+	list_for_each_entry(crtc, &(dev)->mode_config.crtc_list, head)
+
+#endif /* __DRM_CRTC_H__ */