Sync headers with drm-next

Synchronize drm.h, drm_mode.h and drm_fourcc.h to drm-next.

Generated using make headers_install.
Generated from drm-next branch commit 52920704df878050123dfeb469aa6ab8022547c1

Signed-off-by: Simon Ser <contact@emersion.fr>

include/drm/drm.h

@@ -629,8 +629,8 @@ struct drm_gem_open {
 /**
  * DRM_CAP_VBLANK_HIGH_CRTC
  *
- * If set to 1, the kernel supports specifying a CRTC index in the high bits of
+ * If set to 1, the kernel supports specifying a :ref:`CRTC index<crtc_index>`
- * &drm_wait_vblank_request.type.
+ * in the high bits of &drm_wait_vblank_request.type.
  *
  * Starting kernel version 2.6.39, this capability is always set to 1.
  */
@@ -903,6 +903,27 @@ struct drm_syncobj_timeline_wait {
 	__u32 pad;
 };
 
+/**
+ * struct drm_syncobj_eventfd
+ * @handle: syncobj handle.
+ * @flags: Zero to wait for the point to be signalled, or
+ *         &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE to wait for a fence to be
+ *         available for the point.
+ * @point: syncobj timeline point (set to zero for binary syncobjs).
+ * @fd: Existing eventfd to sent events to.
+ * @pad: Must be zero.
+ *
+ * Register an eventfd to be signalled by a syncobj. The eventfd counter will
+ * be incremented by one.
+ */
+struct drm_syncobj_eventfd {
+	__u32 handle;
+	__u32 flags;
+	__u64 point;
+	__s32 fd;
+	__u32 pad;
+};
+
 
 struct drm_syncobj_array {
 	__u64 handles;
@@ -966,6 +987,19 @@ extern "C" {
 #define DRM_IOCTL_GET_STATS             DRM_IOR( 0x06, struct drm_stats)
 #define DRM_IOCTL_SET_VERSION		DRM_IOWR(0x07, struct drm_set_version)
 #define DRM_IOCTL_MODESET_CTL           DRM_IOW(0x08, struct drm_modeset_ctl)
+/**
+ * DRM_IOCTL_GEM_CLOSE - Close a GEM handle.
+ *
+ * GEM handles are not reference-counted by the kernel. User-space is
+ * responsible for managing their lifetime. For example, if user-space imports
+ * the same memory object twice on the same DRM file description, the same GEM
+ * handle is returned by both imports, and user-space needs to ensure
+ * &DRM_IOCTL_GEM_CLOSE is performed once only. The same situation can happen
+ * when a memory object is allocated, then exported and imported again on the
+ * same DRM file description. The &DRM_IOCTL_MODE_GETFB2 IOCTL is an exception
+ * and always returns fresh new GEM handles even if an existing GEM handle
+ * already refers to the same memory object before the IOCTL is performed.
+ */
 #define DRM_IOCTL_GEM_CLOSE		DRM_IOW (0x09, struct drm_gem_close)
 #define DRM_IOCTL_GEM_FLINK		DRM_IOWR(0x0a, struct drm_gem_flink)
 #define DRM_IOCTL_GEM_OPEN		DRM_IOWR(0x0b, struct drm_gem_open)
@@ -1006,7 +1040,37 @@ extern "C" {
 #define DRM_IOCTL_UNLOCK		DRM_IOW( 0x2b, struct drm_lock)
 #define DRM_IOCTL_FINISH		DRM_IOW( 0x2c, struct drm_lock)
 
+/**
+ * DRM_IOCTL_PRIME_HANDLE_TO_FD - Convert a GEM handle to a DMA-BUF FD.
+ *
+ * User-space sets &drm_prime_handle.handle with the GEM handle to export and
+ * &drm_prime_handle.flags, and gets back a DMA-BUF file descriptor in
+ * &drm_prime_handle.fd.
+ *
+ * The export can fail for any driver-specific reason, e.g. because export is
+ * not supported for this specific GEM handle (but might be for others).
+ *
+ * Support for exporting DMA-BUFs is advertised via &DRM_PRIME_CAP_EXPORT.
+ */
 #define DRM_IOCTL_PRIME_HANDLE_TO_FD    DRM_IOWR(0x2d, struct drm_prime_handle)
+/**
+ * DRM_IOCTL_PRIME_FD_TO_HANDLE - Convert a DMA-BUF FD to a GEM handle.
+ *
+ * User-space sets &drm_prime_handle.fd with a DMA-BUF file descriptor to
+ * import, and gets back a GEM handle in &drm_prime_handle.handle.
+ * &drm_prime_handle.flags is unused.
+ *
+ * If an existing GEM handle refers to the memory object backing the DMA-BUF,
+ * that GEM handle is returned. Therefore user-space which needs to handle
+ * arbitrary DMA-BUFs must have a user-space lookup data structure to manually
+ * reference-count duplicated GEM handles. For more information see
+ * &DRM_IOCTL_GEM_CLOSE.
+ *
+ * The import can fail for any driver-specific reason, e.g. because import is
+ * only supported for DMA-BUFs allocated on this DRM device.
+ *
+ * Support for importing DMA-BUFs is advertised via &DRM_PRIME_CAP_IMPORT.
+ */
 #define DRM_IOCTL_PRIME_FD_TO_HANDLE    DRM_IOWR(0x2e, struct drm_prime_handle)
 
 #define DRM_IOCTL_AGP_ACQUIRE		DRM_IO(  0x30)
@@ -1044,6 +1108,16 @@ extern "C" {
 #define DRM_IOCTL_MODE_GETPROPBLOB	DRM_IOWR(0xAC, struct drm_mode_get_blob)
 #define DRM_IOCTL_MODE_GETFB		DRM_IOWR(0xAD, struct drm_mode_fb_cmd)
 #define DRM_IOCTL_MODE_ADDFB		DRM_IOWR(0xAE, struct drm_mode_fb_cmd)
+/**
+ * DRM_IOCTL_MODE_RMFB - Remove a framebuffer.
+ *
+ * This removes a framebuffer previously added via ADDFB/ADDFB2. The IOCTL
+ * argument is a framebuffer object ID.
+ *
+ * Warning: removing a framebuffer currently in-use on an enabled plane will
+ * disable that plane. The CRTC the plane is linked to may also be disabled
+ * (depending on driver capabilities).
+ */
 #define DRM_IOCTL_MODE_RMFB		DRM_IOWR(0xAF, unsigned int)
 #define DRM_IOCTL_MODE_PAGE_FLIP	DRM_IOWR(0xB0, struct drm_mode_crtc_page_flip)
 #define DRM_IOCTL_MODE_DIRTYFB		DRM_IOWR(0xB1, struct drm_mode_fb_dirty_cmd)
@@ -1080,8 +1154,38 @@ extern "C" {
 #define DRM_IOCTL_SYNCOBJ_TRANSFER	DRM_IOWR(0xCC, struct drm_syncobj_transfer)
 #define DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL	DRM_IOWR(0xCD, struct drm_syncobj_timeline_array)
 
+/**
+ * DRM_IOCTL_MODE_GETFB2 - Get framebuffer metadata.
+ *
+ * This queries metadata about a framebuffer. User-space fills
+ * &drm_mode_fb_cmd2.fb_id as the input, and the kernels fills the rest of the
+ * struct as the output.
+ *
+ * If the client is DRM master or has &CAP_SYS_ADMIN, &drm_mode_fb_cmd2.handles
+ * will be filled with GEM buffer handles. Fresh new GEM handles are always
+ * returned, even if another GEM handle referring to the same memory object
+ * already exists on the DRM file description. The caller is responsible for
+ * removing the new handles, e.g. via the &DRM_IOCTL_GEM_CLOSE IOCTL. The same
+ * new handle will be returned for multiple planes in case they use the same
+ * memory object. Planes are valid until one has a zero handle -- this can be
+ * used to compute the number of planes.
+ *
+ * Otherwise, &drm_mode_fb_cmd2.handles will be zeroed and planes are valid
+ * until one has a zero &drm_mode_fb_cmd2.pitches.
+ *
+ * If the framebuffer has a format modifier, &DRM_MODE_FB_MODIFIERS will be set
+ * in &drm_mode_fb_cmd2.flags and &drm_mode_fb_cmd2.modifier will contain the
+ * modifier. Otherwise, user-space must ignore &drm_mode_fb_cmd2.modifier.
+ *
+ * To obtain DMA-BUF FDs for each plane without leaking GEM handles, user-space
+ * can export each handle via &DRM_IOCTL_PRIME_HANDLE_TO_FD, then immediately
+ * close each unique handle via &DRM_IOCTL_GEM_CLOSE, making sure to not
+ * double-close handles which are specified multiple times in the array.
+ */
 #define DRM_IOCTL_MODE_GETFB2		DRM_IOWR(0xCE, struct drm_mode_fb_cmd2)
 
+#define DRM_IOCTL_SYNCOBJ_EVENTFD	DRM_IOWR(0xCF, struct drm_syncobj_eventfd)
+
 /*
  * Device specific ioctls should only be in their respective headers
  * The device specific ioctl range is from 0x40 to 0x9f.

include/drm/drm_fourcc.h

@@ -88,6 +88,18 @@ extern "C" {
  *
  * The authoritative list of format modifier codes is found in
  * `include/uapi/drm/drm_fourcc.h`
+ *
+ * Open Source User Waiver
+ * -----------------------
+ *
+ * Because this is the authoritative source for pixel formats and modifiers
+ * referenced by GL, Vulkan extensions and other standards and hence used both
+ * by open source and closed source driver stacks, the usual requirement for an
+ * upstream in-kernel or open source userspace user does not apply.
+ *
+ * To ensure, as much as feasible, compatibility across stacks and avoid
+ * confusion with incompatible enumerations stakeholders for all relevant driver
+ * stacks should approve additions.
  */
 
 #define fourcc_code(a, b, c, d) ((__u32)(a) | ((__u32)(b) << 8) | \
@@ -645,6 +657,49 @@ extern "C" {
  */
 #define I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC fourcc_mod_code(INTEL, 12)
 
+/*
+ * Intel Color Control Surfaces (CCS) for display ver. 14 render compression.
+ *
+ * The main surface is tile4 and at plane index 0, the CCS is linear and
+ * at index 1. A 64B CCS cache line corresponds to an area of 4x1 tiles in
+ * main surface. In other words, 4 bits in CCS map to a main surface cache
+ * line pair. The main surface pitch is required to be a multiple of four
+ * tile4 widths.
+ */
+#define I915_FORMAT_MOD_4_TILED_MTL_RC_CCS fourcc_mod_code(INTEL, 13)
+
+/*
+ * Intel Color Control Surfaces (CCS) for display ver. 14 media compression
+ *
+ * The main surface is tile4 and at plane index 0, the CCS is linear and
+ * at index 1. A 64B CCS cache line corresponds to an area of 4x1 tiles in
+ * main surface. In other words, 4 bits in CCS map to a main surface cache
+ * line pair. The main surface pitch is required to be a multiple of four
+ * tile4 widths. For semi-planar formats like NV12, CCS planes follow the
+ * Y and UV planes i.e., planes 0 and 1 are used for Y and UV surfaces,
+ * planes 2 and 3 for the respective CCS.
+ */
+#define I915_FORMAT_MOD_4_TILED_MTL_MC_CCS fourcc_mod_code(INTEL, 14)
+
+/*
+ * Intel Color Control Surface with Clear Color (CCS) for display ver. 14 render
+ * compression.
+ *
+ * The main surface is tile4 and is at plane index 0 whereas CCS is linear
+ * and at index 1. The clear color is stored at index 2, and the pitch should
+ * be ignored. The clear color structure is 256 bits. The first 128 bits
+ * represents Raw Clear Color Red, Green, Blue and Alpha color each represented
+ * by 32 bits. The raw clear color is consumed by the 3d engine and generates
+ * the converted clear color of size 64 bits. The first 32 bits store the Lower
+ * Converted Clear Color value and the next 32 bits store the Higher Converted
+ * Clear Color value when applicable. The Converted Clear Color values are
+ * consumed by the DE. The last 64 bits are used to store Color Discard Enable
+ * and Depth Clear Value Valid which are ignored by the DE. A CCS cache line
+ * corresponds to an area of 4x1 tiles in the main surface. The main surface
+ * pitch is required to be a multiple of 4 tile widths.
+ */
+#define I915_FORMAT_MOD_4_TILED_MTL_RC_CCS_CC fourcc_mod_code(INTEL, 15)
+
 /*
  * Tiled, NV12MT, grouped in 64 (pixels) x 32 (lines) -sized macroblocks
  *

include/drm/drm_mode.h

@@ -312,16 +312,48 @@ struct drm_mode_set_plane {
 	__u32 src_w;
 };
 
+/**
+ * struct drm_mode_get_plane - Get plane metadata.
+ *
+ * Userspace can perform a GETPLANE ioctl to retrieve information about a
+ * plane.
+ *
+ * To retrieve the number of formats supported, set @count_format_types to zero
+ * and call the ioctl. @count_format_types will be updated with the value.
+ *
+ * To retrieve these formats, allocate an array with the memory needed to store
+ * @count_format_types formats. Point @format_type_ptr to this array and call
+ * the ioctl again (with @count_format_types still set to the value returned in
+ * the first ioctl call).
+ */
 struct drm_mode_get_plane {
+	/**
+	 * @plane_id: Object ID of the plane whose information should be
+	 * retrieved. Set by caller.
+	 */
 	__u32 plane_id;
 
+	/** @crtc_id: Object ID of the current CRTC. */
 	__u32 crtc_id;
+	/** @fb_id: Object ID of the current fb. */
 	__u32 fb_id;
 
+	/**
+	 * @possible_crtcs: Bitmask of CRTC's compatible with the plane. CRTC's
+	 * are created and they receive an index, which corresponds to their
+	 * position in the bitmask. Bit N corresponds to
+	 * :ref:`CRTC index<crtc_index>` N.
+	 */
 	__u32 possible_crtcs;
+	/** @gamma_size: Never used. */
 	__u32 gamma_size;
 
+	/** @count_format_types: Number of formats. */
 	__u32 count_format_types;
+	/**
+	 * @format_type_ptr: Pointer to ``__u32`` array of formats that are
+	 * supported by the plane. These formats do not require modifiers.
+	 */
 	__u64 format_type_ptr;
 };
 
@@ -509,22 +541,74 @@ struct drm_mode_get_connector {
  */
 #define DRM_MODE_PROP_ATOMIC        0x80000000
 
+/**
+ * struct drm_mode_property_enum - Description for an enum/bitfield entry.
+ * @value: numeric value for this enum entry.
+ * @name: symbolic name for this enum entry.
+ *
+ * See struct drm_property_enum for details.
+ */
 struct drm_mode_property_enum {
 	__u64 value;
 	char name[DRM_PROP_NAME_LEN];
 };
 
+/**
+ * struct drm_mode_get_property - Get property metadata.
+ *
+ * User-space can perform a GETPROPERTY ioctl to retrieve information about a
+ * property. The same property may be attached to multiple objects, see
+ * "Modeset Base Object Abstraction".
+ *
+ * The meaning of the @values_ptr field changes depending on the property type.
+ * See &drm_property.flags for more details.
+ *
+ * The @enum_blob_ptr and @count_enum_blobs fields are only meaningful when the
+ * property has the type &DRM_MODE_PROP_ENUM or &DRM_MODE_PROP_BITMASK. For
+ * backwards compatibility, the kernel will always set @count_enum_blobs to
+ * zero when the property has the type &DRM_MODE_PROP_BLOB. User-space must
+ * ignore these two fields if the property has a different type.
+ *
+ * User-space is expected to retrieve values and enums by performing this ioctl
+ * at least twice: the first time to retrieve the number of elements, the
+ * second time to retrieve the elements themselves.
+ *
+ * To retrieve the number of elements, set @count_values and @count_enum_blobs
+ * to zero, then call the ioctl. @count_values will be updated with the number
+ * of elements. If the property has the type &DRM_MODE_PROP_ENUM or
+ * &DRM_MODE_PROP_BITMASK, @count_enum_blobs will be updated as well.
+ *
+ * To retrieve the elements themselves, allocate an array for @values_ptr and
+ * set @count_values to its capacity. If the property has the type
+ * &DRM_MODE_PROP_ENUM or &DRM_MODE_PROP_BITMASK, allocate an array for
+ * @enum_blob_ptr and set @count_enum_blobs to its capacity. Calling the ioctl
+ * again will fill the arrays.
+ */
 struct drm_mode_get_property {
-	__u64 values_ptr; /* values and blob lengths */
+	/** @values_ptr: Pointer to a ``__u64`` array. */
-	__u64 enum_blob_ptr; /* enum and blob id ptrs */
+	__u64 values_ptr;
+	/** @enum_blob_ptr: Pointer to a struct drm_mode_property_enum array. */
+	__u64 enum_blob_ptr;
 
+	/**
+	 * @prop_id: Object ID of the property which should be retrieved. Set
+	 * by the caller.
+	 */
 	__u32 prop_id;
+	/**
+	 * @flags: ``DRM_MODE_PROP_*`` bitfield. See &drm_property.flags for
+	 * a definition of the flags.
+	 */
 	__u32 flags;
+	/**
+	 * @name: Symbolic property name. User-space should use this field to
+	 * recognize properties.
+	 */
 	char name[DRM_PROP_NAME_LEN];
 
+	/** @count_values: Number of elements in @values_ptr. */
 	__u32 count_values;
-	/* This is only used to count enum values, not blobs. The _blobs is
+	/** @count_enum_blobs: Number of elements in @enum_blob_ptr. */
-	 * simply because of a historical reason, i.e. backwards compat. */
 	__u32 count_enum_blobs;
 };
 
@@ -579,41 +663,73 @@ struct drm_mode_fb_cmd {
 #define DRM_MODE_FB_INTERLACED	(1<<0) /* for interlaced framebuffers */
 #define DRM_MODE_FB_MODIFIERS	(1<<1) /* enables ->modifer[] */
 
+/**
+ * struct drm_mode_fb_cmd2 - Frame-buffer metadata.
+ *
+ * This struct holds frame-buffer metadata. There are two ways to use it:
+ *
+ * - User-space can fill this struct and perform a &DRM_IOCTL_MODE_ADDFB2
+ *   ioctl to register a new frame-buffer. The new frame-buffer object ID will
+ *   be set by the kernel in @fb_id.
+ * - User-space can set @fb_id and perform a &DRM_IOCTL_MODE_GETFB2 ioctl to
+ *   fetch metadata about an existing frame-buffer.
+ *
+ * In case of planar formats, this struct allows up to 4 buffer objects with
+ * offsets and pitches per plane. The pitch and offset order are dictated by
+ * the format FourCC as defined by ``drm_fourcc.h``, e.g. NV12 is described as:
+ *
+ *     YUV 4:2:0 image with a plane of 8-bit Y samples followed by an
+ *     interleaved U/V plane containing 8-bit 2x2 subsampled colour difference
+ *     samples.
+ *
+ * So it would consist of a Y plane at ``offsets[0]`` and a UV plane at
+ * ``offsets[1]``.
+ *
+ * To accommodate tiled, compressed, etc formats, a modifier can be specified.
+ * For more information see the "Format Modifiers" section. Note that even
+ * though it looks like we have a modifier per-plane, we in fact do not. The
+ * modifier for each plane must be identical. Thus all combinations of
+ * different data layouts for multi-plane formats must be enumerated as
+ * separate modifiers.
+ *
+ * All of the entries in @handles, @pitches, @offsets and @modifier must be
+ * zero when unused. Warning, for @offsets and @modifier zero can't be used to
+ * figure out whether the entry is used or not since it's a valid value (a zero
+ * offset is common, and a zero modifier is &DRM_FORMAT_MOD_LINEAR).
+ */
 struct drm_mode_fb_cmd2 {
+	/** @fb_id: Object ID of the frame-buffer. */
 	__u32 fb_id;
+	/** @width: Width of the frame-buffer. */
 	__u32 width;
+	/** @height: Height of the frame-buffer. */
 	__u32 height;
-	__u32 pixel_format; /* fourcc code from drm_fourcc.h */
+	/**
-	__u32 flags; /* see above flags */
+	 * @pixel_format: FourCC format code, see ``DRM_FORMAT_*`` constants in
+	 * ``drm_fourcc.h``.
+	 */
+	__u32 pixel_format;
+	/**
+	 * @flags: Frame-buffer flags (see &DRM_MODE_FB_INTERLACED and
+	 * &DRM_MODE_FB_MODIFIERS).
+	 */
+	__u32 flags;
 
-	/*
+	/**
-	 * In case of planar formats, this ioctl allows up to 4
+	 * @handles: GEM buffer handle, one per plane. Set to 0 if the plane is
-	 * buffer objects with offsets and pitches per plane.
+	 * unused. The same handle can be used for multiple planes.
-	 * The pitch and offset order is dictated by the fourcc,
-	 * e.g. NV12 (https://fourcc.org/yuv.php#NV12) is described as:
-	 *
-	 *   YUV 4:2:0 image with a plane of 8 bit Y samples
-	 *   followed by an interleaved U/V plane containing
-	 *   8 bit 2x2 subsampled colour difference samples.
-	 *
-	 * So it would consist of Y as offsets[0] and UV as
-	 * offsets[1].  Note that offsets[0] will generally
-	 * be 0 (but this is not required).
-	 *
-	 * To accommodate tiled, compressed, etc formats, a
-	 * modifier can be specified.  The default value of zero
-	 * indicates "native" format as specified by the fourcc.
-	 * Vendor specific modifier token.  Note that even though
-	 * it looks like we have a modifier per-plane, we in fact
-	 * do not. The modifier for each plane must be identical.
-	 * Thus all combinations of different data layouts for
-	 * multi plane formats must be enumerated as separate
-	 * modifiers.
 	 */
 	__u32 handles[4];
-	__u32 pitches[4]; /* pitch for each plane */
+	/** @pitches: Pitch (aka. stride) in bytes, one per plane. */
-	__u32 offsets[4]; /* offset of each plane */
+	__u32 pitches[4];
-	__u64 modifier[4]; /* ie, tiling, compress */
+	/** @offsets: Offset into the buffer in bytes, one per plane. */
+	__u32 offsets[4];
+	/**
+	 * @modifier: Format modifier, one per plane. See ``DRM_FORMAT_MOD_*``
+	 * constants in ``drm_fourcc.h``. All planes must use the same
+	 * modifier. Ignored unless &DRM_MODE_FB_MODIFIERS is set in @flags.
+	 */
+	__u64 modifier[4];
 };
 
 #define DRM_MODE_FB_DIRTY_ANNOTATE_COPY 0x01
@@ -718,6 +834,11 @@ struct drm_color_ctm {
 	/*
 	 * Conversion matrix in S31.32 sign-magnitude
 	 * (not two's complement!) format.
+	 *
+	 * out   matrix    in
+	 * |R|   |0 1 2|   |R|
+	 * |G| = |3 4 5| x |G|
+	 * |B|   |6 7 8|   |B|
 	 */
 	__u64 matrix[9];
 };
@@ -762,7 +883,7 @@ struct hdr_metadata_infoframe {
 	 */
 	struct {
 		__u16 x, y;
-		} display_primaries[3];
+	} display_primaries[3];
 	/**
 	 * @white_point: White Point of Colorspace Data.
 	 * These are coded as unsigned 16-bit values in units of
@@ -773,7 +894,7 @@ struct hdr_metadata_infoframe {
 	 */
 	struct {
 		__u16 x, y;
-		} white_point;
+	} white_point;
 	/**
 	 * @max_display_mastering_luminance: Max Mastering Display Luminance.
 	 * This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
@@ -819,12 +940,31 @@ struct hdr_output_metadata {
 	};
 };
 
+/**
+ * DRM_MODE_PAGE_FLIP_EVENT
+ *
+ * Request that the kernel sends back a vblank event (see
+ * struct drm_event_vblank) with the &DRM_EVENT_FLIP_COMPLETE type when the
+ * page-flip is done.
+ */
 #define DRM_MODE_PAGE_FLIP_EVENT 0x01
+/**
+ * DRM_MODE_PAGE_FLIP_ASYNC
+ *
+ * Request that the page-flip is performed as soon as possible, ie. with no
+ * delay due to waiting for vblank. This may cause tearing to be visible on
+ * the screen.
+ */
 #define DRM_MODE_PAGE_FLIP_ASYNC 0x02
 #define DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE 0x4
 #define DRM_MODE_PAGE_FLIP_TARGET_RELATIVE 0x8
 #define DRM_MODE_PAGE_FLIP_TARGET (DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE | \
 				   DRM_MODE_PAGE_FLIP_TARGET_RELATIVE)
+/**
+ * DRM_MODE_PAGE_FLIP_FLAGS
+ *
+ * Bitmask of flags suitable for &drm_mode_crtc_page_flip_target.flags.
+ */
 #define DRM_MODE_PAGE_FLIP_FLAGS (DRM_MODE_PAGE_FLIP_EVENT | \
 				  DRM_MODE_PAGE_FLIP_ASYNC | \
 				  DRM_MODE_PAGE_FLIP_TARGET)
@@ -918,11 +1058,53 @@ struct drm_mode_destroy_dumb {
 	__u32 handle;
 };
 
-/* page-flip flags are valid, plus: */
+/**
+ * DRM_MODE_ATOMIC_TEST_ONLY
+ *
+ * Do not apply the atomic commit, instead check whether the hardware supports
+ * this configuration.
+ *
+ * See &drm_mode_config_funcs.atomic_check for more details on test-only
+ * commits.
+ */
 #define DRM_MODE_ATOMIC_TEST_ONLY 0x0100
+/**
+ * DRM_MODE_ATOMIC_NONBLOCK
+ *
+ * Do not block while applying the atomic commit. The &DRM_IOCTL_MODE_ATOMIC
+ * IOCTL returns immediately instead of waiting for the changes to be applied
+ * in hardware. Note, the driver will still check that the update can be
+ * applied before retuning.
+ */
 #define DRM_MODE_ATOMIC_NONBLOCK  0x0200
+/**
+ * DRM_MODE_ATOMIC_ALLOW_MODESET
+ *
+ * Allow the update to result in temporary or transient visible artifacts while
+ * the update is being applied. Applying the update may also take significantly
+ * more time than a page flip. All visual artifacts will disappear by the time
+ * the update is completed, as signalled through the vblank event's timestamp
+ * (see struct drm_event_vblank).
+ *
+ * This flag must be set when the KMS update might cause visible artifacts.
+ * Without this flag such KMS update will return a EINVAL error. What kind of
+ * update may cause visible artifacts depends on the driver and the hardware.
+ * User-space that needs to know beforehand if an update might cause visible
+ * artifacts can use &DRM_MODE_ATOMIC_TEST_ONLY without
+ * &DRM_MODE_ATOMIC_ALLOW_MODESET to see if it fails.
+ *
+ * To the best of the driver's knowledge, visual artifacts are guaranteed to
+ * not appear when this flag is not set. Some sinks might display visual
+ * artifacts outside of the driver's control.
+ */
 #define DRM_MODE_ATOMIC_ALLOW_MODESET 0x0400
 
+/**
+ * DRM_MODE_ATOMIC_FLAGS
+ *
+ * Bitfield of flags accepted by the &DRM_IOCTL_MODE_ATOMIC IOCTL in
+ * &drm_mode_atomic.flags.
+ */
 #define DRM_MODE_ATOMIC_FLAGS (\
 		DRM_MODE_PAGE_FLIP_EVENT |\
 		DRM_MODE_PAGE_FLIP_ASYNC |\
@@ -1026,6 +1208,10 @@ struct drm_mode_destroy_blob {
  * struct drm_mode_create_lease - Create lease
  *
  * Lease mode resources, creating another drm_master.
+ *
+ * The @object_ids array must reference at least one CRTC, one connector and
+ * one plane if &DRM_CLIENT_CAP_UNIVERSAL_PLANES is enabled. Alternatively,
+ * the lease can be completely empty.
  */
 struct drm_mode_create_lease {
 	/** @object_ids: Pointer to array of object ids (__u32) */