driver core: Return proper error code when dev_set_name() fails

[linux.git] / include / uapi / drm / drm_mode.h

/*
 * Copyright (c) 2007 Dave Airlie <[email protected]>
 * Copyright (c) 2007 Jakob Bornecrantz <[email protected]>
 * Copyright (c) 2008 Red Hat Inc.
 * Copyright (c) 2007-2008 Tungsten Graphics, Inc., Cedar Park, TX., USA
 * Copyright (c) 2007-2008 Intel Corporation
 *
 * 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
 * AUTHORS OR COPYRIGHT HOLDERS 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_MODE_H
#define _DRM_MODE_H

#include "drm.h"

#if defined(__cplusplus)
extern "C" {
#endif

/**
 * DOC: overview
 *
 * DRM exposes many UAPI and structure definition to have a consistent
 * and standardized interface with user.
 * Userspace can refer to these structure definitions and UAPI formats
 * to communicate to driver
 */

#define DRM_CONNECTOR_NAME_LEN  32
#define DRM_DISPLAY_MODE_LEN    32
#define DRM_PROP_NAME_LEN       32

#define DRM_MODE_TYPE_BUILTIN   (1<<0) /* deprecated */
#define DRM_MODE_TYPE_CLOCK_C   ((1<<1) | DRM_MODE_TYPE_BUILTIN) /* deprecated */
#define DRM_MODE_TYPE_CRTC_C    ((1<<2) | DRM_MODE_TYPE_BUILTIN) /* deprecated */
#define DRM_MODE_TYPE_PREFERRED (1<<3)
#define DRM_MODE_TYPE_DEFAULT   (1<<4) /* deprecated */
#define DRM_MODE_TYPE_USERDEF   (1<<5)
#define DRM_MODE_TYPE_DRIVER    (1<<6)

#define DRM_MODE_TYPE_ALL       (DRM_MODE_TYPE_PREFERRED |      \
                                 DRM_MODE_TYPE_USERDEF |        \
                                 DRM_MODE_TYPE_DRIVER)

/* Video mode flags */
/* bit compatible with the xrandr RR_ definitions (bits 0-13)
 *
 * ABI warning: Existing userspace really expects
 * the mode flags to match the xrandr definitions. Any
 * changes that don't match the xrandr definitions will
 * likely need a new client cap or some other mechanism
 * to avoid breaking existing userspace. This includes
 * allocating new flags in the previously unused bits!
 */
#define DRM_MODE_FLAG_PHSYNC                    (1<<0)
#define DRM_MODE_FLAG_NHSYNC                    (1<<1)
#define DRM_MODE_FLAG_PVSYNC                    (1<<2)
#define DRM_MODE_FLAG_NVSYNC                    (1<<3)
#define DRM_MODE_FLAG_INTERLACE                 (1<<4)
#define DRM_MODE_FLAG_DBLSCAN                   (1<<5)
#define DRM_MODE_FLAG_CSYNC                     (1<<6)
#define DRM_MODE_FLAG_PCSYNC                    (1<<7)
#define DRM_MODE_FLAG_NCSYNC                    (1<<8)
#define DRM_MODE_FLAG_HSKEW                     (1<<9) /* hskew provided */
#define DRM_MODE_FLAG_BCAST                     (1<<10) /* deprecated */
#define DRM_MODE_FLAG_PIXMUX                    (1<<11) /* deprecated */
#define DRM_MODE_FLAG_DBLCLK                    (1<<12)
#define DRM_MODE_FLAG_CLKDIV2                   (1<<13)
 /*
  * When adding a new stereo mode don't forget to adjust DRM_MODE_FLAGS_3D_MAX
  * (define not exposed to user space).
  */
#define DRM_MODE_FLAG_3D_MASK                   (0x1f<<14)
#define  DRM_MODE_FLAG_3D_NONE          (0<<14)
#define  DRM_MODE_FLAG_3D_FRAME_PACKING         (1<<14)
#define  DRM_MODE_FLAG_3D_FIELD_ALTERNATIVE     (2<<14)
#define  DRM_MODE_FLAG_3D_LINE_ALTERNATIVE      (3<<14)
#define  DRM_MODE_FLAG_3D_SIDE_BY_SIDE_FULL     (4<<14)
#define  DRM_MODE_FLAG_3D_L_DEPTH               (5<<14)
#define  DRM_MODE_FLAG_3D_L_DEPTH_GFX_GFX_DEPTH (6<<14)
#define  DRM_MODE_FLAG_3D_TOP_AND_BOTTOM        (7<<14)
#define  DRM_MODE_FLAG_3D_SIDE_BY_SIDE_HALF     (8<<14)

/* Picture aspect ratio options */
#define DRM_MODE_PICTURE_ASPECT_NONE            0
#define DRM_MODE_PICTURE_ASPECT_4_3             1
#define DRM_MODE_PICTURE_ASPECT_16_9            2
#define DRM_MODE_PICTURE_ASPECT_64_27           3
#define DRM_MODE_PICTURE_ASPECT_256_135         4

/* Content type options */
#define DRM_MODE_CONTENT_TYPE_NO_DATA           0
#define DRM_MODE_CONTENT_TYPE_GRAPHICS          1
#define DRM_MODE_CONTENT_TYPE_PHOTO             2
#define DRM_MODE_CONTENT_TYPE_CINEMA            3
#define DRM_MODE_CONTENT_TYPE_GAME              4

/* Aspect ratio flag bitmask (4 bits 22:19) */
#define DRM_MODE_FLAG_PIC_AR_MASK               (0x0F<<19)
#define  DRM_MODE_FLAG_PIC_AR_NONE \
                        (DRM_MODE_PICTURE_ASPECT_NONE<<19)
#define  DRM_MODE_FLAG_PIC_AR_4_3 \
                        (DRM_MODE_PICTURE_ASPECT_4_3<<19)
#define  DRM_MODE_FLAG_PIC_AR_16_9 \
                        (DRM_MODE_PICTURE_ASPECT_16_9<<19)
#define  DRM_MODE_FLAG_PIC_AR_64_27 \
                        (DRM_MODE_PICTURE_ASPECT_64_27<<19)
#define  DRM_MODE_FLAG_PIC_AR_256_135 \
                        (DRM_MODE_PICTURE_ASPECT_256_135<<19)

#define  DRM_MODE_FLAG_ALL      (DRM_MODE_FLAG_PHSYNC |         \
                                 DRM_MODE_FLAG_NHSYNC |         \
                                 DRM_MODE_FLAG_PVSYNC |         \
                                 DRM_MODE_FLAG_NVSYNC |         \
                                 DRM_MODE_FLAG_INTERLACE |      \
                                 DRM_MODE_FLAG_DBLSCAN |        \
                                 DRM_MODE_FLAG_CSYNC |          \
                                 DRM_MODE_FLAG_PCSYNC |         \
                                 DRM_MODE_FLAG_NCSYNC |         \
                                 DRM_MODE_FLAG_HSKEW |          \
                                 DRM_MODE_FLAG_DBLCLK |         \
                                 DRM_MODE_FLAG_CLKDIV2 |        \
                                 DRM_MODE_FLAG_3D_MASK)

/* DPMS flags */
/* bit compatible with the xorg definitions. */
#define DRM_MODE_DPMS_ON        0
#define DRM_MODE_DPMS_STANDBY   1
#define DRM_MODE_DPMS_SUSPEND   2
#define DRM_MODE_DPMS_OFF       3

/* Scaling mode options */
#define DRM_MODE_SCALE_NONE             0 /* Unmodified timing (display or
                                             software can still scale) */
#define DRM_MODE_SCALE_FULLSCREEN       1 /* Full screen, ignore aspect */
#define DRM_MODE_SCALE_CENTER           2 /* Centered, no scaling */
#define DRM_MODE_SCALE_ASPECT           3 /* Full screen, preserve aspect */

/* Dithering mode options */
#define DRM_MODE_DITHERING_OFF  0
#define DRM_MODE_DITHERING_ON   1
#define DRM_MODE_DITHERING_AUTO 2

/* Dirty info options */
#define DRM_MODE_DIRTY_OFF      0
#define DRM_MODE_DIRTY_ON       1
#define DRM_MODE_DIRTY_ANNOTATE 2

/* Link Status options */
#define DRM_MODE_LINK_STATUS_GOOD       0
#define DRM_MODE_LINK_STATUS_BAD        1

/*
 * DRM_MODE_ROTATE_<degrees>
 *
 * Signals that a drm plane is been rotated <degrees> degrees in counter
 * clockwise direction.
 *
 * This define is provided as a convenience, looking up the property id
 * using the name->prop id lookup is the preferred method.
 */
#define DRM_MODE_ROTATE_0       (1<<0)
#define DRM_MODE_ROTATE_90      (1<<1)
#define DRM_MODE_ROTATE_180     (1<<2)
#define DRM_MODE_ROTATE_270     (1<<3)

/*
 * DRM_MODE_ROTATE_MASK
 *
 * Bitmask used to look for drm plane rotations.
 */
#define DRM_MODE_ROTATE_MASK (\
                DRM_MODE_ROTATE_0  | \
                DRM_MODE_ROTATE_90  | \
                DRM_MODE_ROTATE_180 | \
                DRM_MODE_ROTATE_270)

/*
 * DRM_MODE_REFLECT_<axis>
 *
 * Signals that the contents of a drm plane is reflected along the <axis> axis,
 * in the same way as mirroring.
 * See kerneldoc chapter "Plane Composition Properties" for more details.
 *
 * This define is provided as a convenience, looking up the property id
 * using the name->prop id lookup is the preferred method.
 */
#define DRM_MODE_REFLECT_X      (1<<4)
#define DRM_MODE_REFLECT_Y      (1<<5)

/*
 * DRM_MODE_REFLECT_MASK
 *
 * Bitmask used to look for drm plane reflections.
 */
#define DRM_MODE_REFLECT_MASK (\
                DRM_MODE_REFLECT_X | \
                DRM_MODE_REFLECT_Y)

/* Content Protection Flags */
#define DRM_MODE_CONTENT_PROTECTION_UNDESIRED   0
#define DRM_MODE_CONTENT_PROTECTION_DESIRED     1
#define DRM_MODE_CONTENT_PROTECTION_ENABLED     2

/**
 * struct drm_mode_modeinfo - Display mode information.
 * @clock: pixel clock in kHz
 * @hdisplay: horizontal display size
 * @hsync_start: horizontal sync start
 * @hsync_end: horizontal sync end
 * @htotal: horizontal total size
 * @hskew: horizontal skew
 * @vdisplay: vertical display size
 * @vsync_start: vertical sync start
 * @vsync_end: vertical sync end
 * @vtotal: vertical total size
 * @vscan: vertical scan
 * @vrefresh: approximate vertical refresh rate in Hz
 * @flags: bitmask of misc. flags, see DRM_MODE_FLAG_* defines
 * @type: bitmask of type flags, see DRM_MODE_TYPE_* defines
 * @name: string describing the mode resolution
 *
 * This is the user-space API display mode information structure. For the
 * kernel version see struct drm_display_mode.
 */
struct drm_mode_modeinfo {
        __u32 clock;
        __u16 hdisplay;
        __u16 hsync_start;
        __u16 hsync_end;
        __u16 htotal;
        __u16 hskew;
        __u16 vdisplay;
        __u16 vsync_start;
        __u16 vsync_end;
        __u16 vtotal;
        __u16 vscan;

        __u32 vrefresh;

        __u32 flags;
        __u32 type;
        char name[DRM_DISPLAY_MODE_LEN];
};

struct drm_mode_card_res {
        __u64 fb_id_ptr;
        __u64 crtc_id_ptr;
        __u64 connector_id_ptr;
        __u64 encoder_id_ptr;
        __u32 count_fbs;
        __u32 count_crtcs;
        __u32 count_connectors;
        __u32 count_encoders;
        __u32 min_width;
        __u32 max_width;
        __u32 min_height;
        __u32 max_height;
};

struct drm_mode_crtc {
        __u64 set_connectors_ptr;
        __u32 count_connectors;

        __u32 crtc_id; /**< Id */
        __u32 fb_id; /**< Id of framebuffer */

        __u32 x; /**< x Position on the framebuffer */
        __u32 y; /**< y Position on the framebuffer */

        __u32 gamma_size;
        __u32 mode_valid;
        struct drm_mode_modeinfo mode;
};

#define DRM_MODE_PRESENT_TOP_FIELD      (1<<0)
#define DRM_MODE_PRESENT_BOTTOM_FIELD   (1<<1)

/* Planes blend with or override other bits on the CRTC */
struct drm_mode_set_plane {
        __u32 plane_id;
        __u32 crtc_id;
        __u32 fb_id; /* fb object contains surface format type */
        __u32 flags; /* see above flags */

        /* Signed dest location allows it to be partially off screen */
        __s32 crtc_x;
        __s32 crtc_y;
        __u32 crtc_w;
        __u32 crtc_h;

        /* Source values are 16.16 fixed point */
        __u32 src_x;
        __u32 src_y;
        __u32 src_h;
        __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;
};

struct drm_mode_get_plane_res {
        __u64 plane_id_ptr;
        __u32 count_planes;
};

#define DRM_MODE_ENCODER_NONE   0
#define DRM_MODE_ENCODER_DAC    1
#define DRM_MODE_ENCODER_TMDS   2
#define DRM_MODE_ENCODER_LVDS   3
#define DRM_MODE_ENCODER_TVDAC  4
#define DRM_MODE_ENCODER_VIRTUAL 5
#define DRM_MODE_ENCODER_DSI    6
#define DRM_MODE_ENCODER_DPMST  7
#define DRM_MODE_ENCODER_DPI    8

struct drm_mode_get_encoder {
        __u32 encoder_id;
        __u32 encoder_type;

        __u32 crtc_id; /**< Id of crtc */

        __u32 possible_crtcs;
        __u32 possible_clones;
};

/* This is for connectors with multiple signal types. */
/* Try to match DRM_MODE_CONNECTOR_X as closely as possible. */
enum drm_mode_subconnector {
        DRM_MODE_SUBCONNECTOR_Automatic   = 0,  /* DVI-I, TV     */
        DRM_MODE_SUBCONNECTOR_Unknown     = 0,  /* DVI-I, TV, DP */
        DRM_MODE_SUBCONNECTOR_VGA         = 1,  /*            DP */
        DRM_MODE_SUBCONNECTOR_DVID        = 3,  /* DVI-I      DP */
        DRM_MODE_SUBCONNECTOR_DVIA        = 4,  /* DVI-I         */
        DRM_MODE_SUBCONNECTOR_Composite   = 5,  /*        TV     */
        DRM_MODE_SUBCONNECTOR_SVIDEO      = 6,  /*        TV     */
        DRM_MODE_SUBCONNECTOR_Component   = 8,  /*        TV     */
        DRM_MODE_SUBCONNECTOR_SCART       = 9,  /*        TV     */
        DRM_MODE_SUBCONNECTOR_DisplayPort = 10, /*            DP */
        DRM_MODE_SUBCONNECTOR_HDMIA       = 11, /*            DP */
        DRM_MODE_SUBCONNECTOR_Native      = 15, /*            DP */
        DRM_MODE_SUBCONNECTOR_Wireless    = 18, /*            DP */
};

#define DRM_MODE_CONNECTOR_Unknown      0
#define DRM_MODE_CONNECTOR_VGA          1
#define DRM_MODE_CONNECTOR_DVII         2
#define DRM_MODE_CONNECTOR_DVID         3
#define DRM_MODE_CONNECTOR_DVIA         4
#define DRM_MODE_CONNECTOR_Composite    5
#define DRM_MODE_CONNECTOR_SVIDEO       6
#define DRM_MODE_CONNECTOR_LVDS         7
#define DRM_MODE_CONNECTOR_Component    8
#define DRM_MODE_CONNECTOR_9PinDIN      9
#define DRM_MODE_CONNECTOR_DisplayPort  10
#define DRM_MODE_CONNECTOR_HDMIA        11
#define DRM_MODE_CONNECTOR_HDMIB        12
#define DRM_MODE_CONNECTOR_TV           13
#define DRM_MODE_CONNECTOR_eDP          14
#define DRM_MODE_CONNECTOR_VIRTUAL      15
#define DRM_MODE_CONNECTOR_DSI          16
#define DRM_MODE_CONNECTOR_DPI          17
#define DRM_MODE_CONNECTOR_WRITEBACK    18
#define DRM_MODE_CONNECTOR_SPI          19
#define DRM_MODE_CONNECTOR_USB          20

/**
 * struct drm_mode_get_connector - Get connector metadata.
 *
 * User-space can perform a GETCONNECTOR ioctl to retrieve information about a
 * connector. User-space is expected to retrieve encoders, modes and properties
 * 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_props and @count_encoders to
 * zero, set @count_modes to 1, and set @modes_ptr to a temporary struct
 * drm_mode_modeinfo element.
 *
 * To retrieve the elements, allocate arrays for @encoders_ptr, @modes_ptr,
 * @props_ptr and @prop_values_ptr, then set @count_modes, @count_props and
 * @count_encoders to their capacity.
 *
 * Performing the ioctl only twice may be racy: the number of elements may have
 * changed with a hotplug event in-between the two ioctls. User-space is
 * expected to retry the last ioctl until the number of elements stabilizes.
 * The kernel won't fill any array which doesn't have the expected length.
 *
 * **Force-probing a connector**
 *
 * If the @count_modes field is set to zero and the DRM client is the current
 * DRM master, the kernel will perform a forced probe on the connector to
 * refresh the connector status, modes and EDID. A forced-probe can be slow,
 * might cause flickering and the ioctl will block.
 *
 * User-space needs to force-probe connectors to ensure their metadata is
 * up-to-date at startup and after receiving a hot-plug event. User-space
 * may perform a forced-probe when the user explicitly requests it. User-space
 * shouldn't perform a forced-probe in other situations.
 */
struct drm_mode_get_connector {
        /** @encoders_ptr: Pointer to ``__u32`` array of object IDs. */
        __u64 encoders_ptr;
        /** @modes_ptr: Pointer to struct drm_mode_modeinfo array. */
        __u64 modes_ptr;
        /** @props_ptr: Pointer to ``__u32`` array of property IDs. */
        __u64 props_ptr;
        /** @prop_values_ptr: Pointer to ``__u64`` array of property values. */
        __u64 prop_values_ptr;

        /** @count_modes: Number of modes. */
        __u32 count_modes;
        /** @count_props: Number of properties. */
        __u32 count_props;
        /** @count_encoders: Number of encoders. */
        __u32 count_encoders;

        /** @encoder_id: Object ID of the current encoder. */
        __u32 encoder_id;
        /** @connector_id: Object ID of the connector. */
        __u32 connector_id;
        /**
         * @connector_type: Type of the connector.
         *
         * See DRM_MODE_CONNECTOR_* defines.
         */
        __u32 connector_type;
        /**
         * @connector_type_id: Type-specific connector number.
         *
         * This is not an object ID. This is a per-type connector number. Each
         * (type, type_id) combination is unique across all connectors of a DRM
         * device.
         */
        __u32 connector_type_id;

        /**
         * @connection: Status of the connector.
         *
         * See enum drm_connector_status.
         */
        __u32 connection;
        /** @mm_width: Width of the connected sink in millimeters. */
        __u32 mm_width;
        /** @mm_height: Height of the connected sink in millimeters. */
        __u32 mm_height;
        /**
         * @subpixel: Subpixel order of the connected sink.
         *
         * See enum subpixel_order.
         */
        __u32 subpixel;

        /** @pad: Padding, must be zero. */
        __u32 pad;
};

#define DRM_MODE_PROP_PENDING   (1<<0) /* deprecated, do not use */
#define DRM_MODE_PROP_RANGE     (1<<1)
#define DRM_MODE_PROP_IMMUTABLE (1<<2)
#define DRM_MODE_PROP_ENUM      (1<<3) /* enumerated type with text strings */
#define DRM_MODE_PROP_BLOB      (1<<4)
#define DRM_MODE_PROP_BITMASK   (1<<5) /* bitmask of enumerated types */

/* non-extended types: legacy bitmask, one bit per type: */
#define DRM_MODE_PROP_LEGACY_TYPE  ( \
                DRM_MODE_PROP_RANGE | \
                DRM_MODE_PROP_ENUM | \
                DRM_MODE_PROP_BLOB | \
                DRM_MODE_PROP_BITMASK)

/* extended-types: rather than continue to consume a bit per type,
 * grab a chunk of the bits to use as integer type id.
 */
#define DRM_MODE_PROP_EXTENDED_TYPE     0x0000ffc0
#define DRM_MODE_PROP_TYPE(n)           ((n) << 6)
#define DRM_MODE_PROP_OBJECT            DRM_MODE_PROP_TYPE(1)
#define DRM_MODE_PROP_SIGNED_RANGE      DRM_MODE_PROP_TYPE(2)

/* the PROP_ATOMIC flag is used to hide properties from userspace that
 * is not aware of atomic properties.  This is mostly to work around
 * older userspace (DDX drivers) that read/write each prop they find,
 * witout being aware that this could be triggering a lengthy modeset.
 */
#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 {
        /** @values_ptr: Pointer to a ``__u64`` array. */
        __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;
        /** @count_enum_blobs: Number of elements in @enum_blob_ptr. */
        __u32 count_enum_blobs;
};

struct drm_mode_connector_set_property {
        __u64 value;
        __u32 prop_id;
        __u32 connector_id;
};

#define DRM_MODE_OBJECT_CRTC 0xcccccccc
#define DRM_MODE_OBJECT_CONNECTOR 0xc0c0c0c0
#define DRM_MODE_OBJECT_ENCODER 0xe0e0e0e0
#define DRM_MODE_OBJECT_MODE 0xdededede
#define DRM_MODE_OBJECT_PROPERTY 0xb0b0b0b0
#define DRM_MODE_OBJECT_FB 0xfbfbfbfb
#define DRM_MODE_OBJECT_BLOB 0xbbbbbbbb
#define DRM_MODE_OBJECT_PLANE 0xeeeeeeee
#define DRM_MODE_OBJECT_ANY 0

struct drm_mode_obj_get_properties {
        __u64 props_ptr;
        __u64 prop_values_ptr;
        __u32 count_props;
        __u32 obj_id;
        __u32 obj_type;
};

struct drm_mode_obj_set_property {
        __u64 value;
        __u32 prop_id;
        __u32 obj_id;
        __u32 obj_type;
};

struct drm_mode_get_blob {
        __u32 blob_id;
        __u32 length;
        __u64 data;
};

struct drm_mode_fb_cmd {
        __u32 fb_id;
        __u32 width;
        __u32 height;
        __u32 pitch;
        __u32 bpp;
        __u32 depth;
        /* driver specific handle */
        __u32 handle;
};

#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;
        /**
         * @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;

        /**
         * @handles: GEM buffer handle, one per plane. Set to 0 if the plane is
         * unused. The same handle can be used for multiple planes.
         */
        __u32 handles[4];
        /** @pitches: Pitch (aka. stride) in bytes, one per plane. */
        __u32 pitches[4];
        /** @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
#define DRM_MODE_FB_DIRTY_ANNOTATE_FILL 0x02
#define DRM_MODE_FB_DIRTY_FLAGS         0x03

#define DRM_MODE_FB_DIRTY_MAX_CLIPS     256

/*
 * Mark a region of a framebuffer as dirty.
 *
 * Some hardware does not automatically update display contents
 * as a hardware or software draw to a framebuffer. This ioctl
 * allows userspace to tell the kernel and the hardware what
 * regions of the framebuffer have changed.
 *
 * The kernel or hardware is free to update more then just the
 * region specified by the clip rects. The kernel or hardware
 * may also delay and/or coalesce several calls to dirty into a
 * single update.
 *
 * Userspace may annotate the updates, the annotates are a
 * promise made by the caller that the change is either a copy
 * of pixels or a fill of a single color in the region specified.
 *
 * If the DRM_MODE_FB_DIRTY_ANNOTATE_COPY flag is given then
 * the number of updated regions are half of num_clips given,
 * where the clip rects are paired in src and dst. The width and
 * height of each one of the pairs must match.
 *
 * If the DRM_MODE_FB_DIRTY_ANNOTATE_FILL flag is given the caller
 * promises that the region specified of the clip rects is filled
 * completely with a single color as given in the color argument.
 */

struct drm_mode_fb_dirty_cmd {
        __u32 fb_id;
        __u32 flags;
        __u32 color;
        __u32 num_clips;
        __u64 clips_ptr;
};

struct drm_mode_mode_cmd {
        __u32 connector_id;
        struct drm_mode_modeinfo mode;
};

#define DRM_MODE_CURSOR_BO      0x01
#define DRM_MODE_CURSOR_MOVE    0x02
#define DRM_MODE_CURSOR_FLAGS   0x03

/*
 * depending on the value in flags different members are used.
 *
 * CURSOR_BO uses
 *    crtc_id
 *    width
 *    height
 *    handle - if 0 turns the cursor off
 *
 * CURSOR_MOVE uses
 *    crtc_id
 *    x
 *    y
 */
struct drm_mode_cursor {
        __u32 flags;
        __u32 crtc_id;
        __s32 x;
        __s32 y;
        __u32 width;
        __u32 height;
        /* driver specific handle */
        __u32 handle;
};

struct drm_mode_cursor2 {
        __u32 flags;
        __u32 crtc_id;
        __s32 x;
        __s32 y;
        __u32 width;
        __u32 height;
        /* driver specific handle */
        __u32 handle;
        __s32 hot_x;
        __s32 hot_y;
};

struct drm_mode_crtc_lut {
        __u32 crtc_id;
        __u32 gamma_size;

        /* pointers to arrays */
        __u64 red;
        __u64 green;
        __u64 blue;
};

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];
};

struct drm_color_lut {
        /*
         * Values are mapped linearly to 0.0 - 1.0 range, with 0x0 == 0.0 and
         * 0xffff == 1.0.
         */
        __u16 red;
        __u16 green;
        __u16 blue;
        __u16 reserved;
};

/**
 * struct hdr_metadata_infoframe - HDR Metadata Infoframe Data.
 *
 * HDR Metadata Infoframe as per CTA 861.G spec. This is expected
 * to match exactly with the spec.
 *
 * Userspace is expected to pass the metadata information as per
 * the format described in this structure.
 */
struct hdr_metadata_infoframe {
        /**
         * @eotf: Electro-Optical Transfer Function (EOTF)
         * used in the stream.
         */
        __u8 eotf;
        /**
         * @metadata_type: Static_Metadata_Descriptor_ID.
         */
        __u8 metadata_type;
        /**
         * @display_primaries: Color Primaries of the Data.
         * These are coded as unsigned 16-bit values in units of
         * 0.00002, where 0x0000 represents zero and 0xC350
         * represents 1.0000.
         * @display_primaries.x: X cordinate of color primary.
         * @display_primaries.y: Y cordinate of color primary.
         */
        struct {
                __u16 x, y;
                } display_primaries[3];
        /**
         * @white_point: White Point of Colorspace Data.
         * These are coded as unsigned 16-bit values in units of
         * 0.00002, where 0x0000 represents zero and 0xC350
         * represents 1.0000.
         * @white_point.x: X cordinate of whitepoint of color primary.
         * @white_point.y: Y cordinate of whitepoint of color primary.
         */
        struct {
                __u16 x, y;
                } 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,
         * where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
         */
        __u16 max_display_mastering_luminance;
        /**
         * @min_display_mastering_luminance: Min Mastering Display Luminance.
         * This value is coded as an unsigned 16-bit value in units of
         * 0.0001 cd/m2, where 0x0001 represents 0.0001 cd/m2 and 0xFFFF
         * represents 6.5535 cd/m2.
         */
        __u16 min_display_mastering_luminance;
        /**
         * @max_cll: Max Content Light Level.
         * This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
         * where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
         */
        __u16 max_cll;
        /**
         * @max_fall: Max Frame Average Light Level.
         * This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
         * where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
         */
        __u16 max_fall;
};

/**
 * struct hdr_output_metadata - HDR output metadata
 *
 * Metadata Information to be passed from userspace
 */
struct hdr_output_metadata {
        /**
         * @metadata_type: Static_Metadata_Descriptor_ID.
         */
        __u32 metadata_type;
        /**
         * @hdmi_metadata_type1: HDR Metadata Infoframe.
         */
        union {
                struct hdr_metadata_infoframe hdmi_metadata_type1;
        };
};

/**
 * 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)

/*
 * Request a page flip on the specified crtc.
 *
 * This ioctl will ask KMS to schedule a page flip for the specified
 * crtc.  Once any pending rendering targeting the specified fb (as of
 * ioctl time) has completed, the crtc will be reprogrammed to display
 * that fb after the next vertical refresh.  The ioctl returns
 * immediately, but subsequent rendering to the current fb will block
 * in the execbuffer ioctl until the page flip happens.  If a page
 * flip is already pending as the ioctl is called, EBUSY will be
 * returned.
 *
 * Flag DRM_MODE_PAGE_FLIP_EVENT requests that drm sends back a vblank
 * event (see drm.h: struct drm_event_vblank) when the page flip is
 * done.  The user_data field passed in with this ioctl will be
 * returned as the user_data field in the vblank event struct.
 *
 * Flag DRM_MODE_PAGE_FLIP_ASYNC requests that the flip happen
 * 'as soon as possible', meaning that it not delay waiting for vblank.
 * This may cause tearing on the screen.
 *
 * The reserved field must be zero.
 */

struct drm_mode_crtc_page_flip {
        __u32 crtc_id;
        __u32 fb_id;
        __u32 flags;
        __u32 reserved;
        __u64 user_data;
};

/*
 * Request a page flip on the specified crtc.
 *
 * Same as struct drm_mode_crtc_page_flip, but supports new flags and
 * re-purposes the reserved field:
 *
 * The sequence field must be zero unless either of the
 * DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE/RELATIVE flags is specified. When
 * the ABSOLUTE flag is specified, the sequence field denotes the absolute
 * vblank sequence when the flip should take effect. When the RELATIVE
 * flag is specified, the sequence field denotes the relative (to the
 * current one when the ioctl is called) vblank sequence when the flip
 * should take effect. NOTE: DRM_IOCTL_WAIT_VBLANK must still be used to
 * make sure the vblank sequence before the target one has passed before
 * calling this ioctl. The purpose of the
 * DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE/RELATIVE flags is merely to clarify
 * the target for when code dealing with a page flip runs during a
 * vertical blank period.
 */

struct drm_mode_crtc_page_flip_target {
        __u32 crtc_id;
        __u32 fb_id;
        __u32 flags;
        __u32 sequence;
        __u64 user_data;
};

/* create a dumb scanout buffer */
struct drm_mode_create_dumb {
        __u32 height;
        __u32 width;
        __u32 bpp;
        __u32 flags;
        /* handle, pitch, size will be returned */
        __u32 handle;
        __u32 pitch;
        __u64 size;
};

/* set up for mmap of a dumb scanout buffer */
struct drm_mode_map_dumb {
        /** Handle for the object being mapped. */
        __u32 handle;
        __u32 pad;
        /**
         * Fake offset to use for subsequent mmap call
         *
         * This is a fixed-size type for 32/64 compatibility.
         */
        __u64 offset;
};

struct drm_mode_destroy_dumb {
        __u32 handle;
};

/**
 * 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 |\
                DRM_MODE_ATOMIC_TEST_ONLY |\
                DRM_MODE_ATOMIC_NONBLOCK |\
                DRM_MODE_ATOMIC_ALLOW_MODESET)

struct drm_mode_atomic {
        __u32 flags;
        __u32 count_objs;
        __u64 objs_ptr;
        __u64 count_props_ptr;
        __u64 props_ptr;
        __u64 prop_values_ptr;
        __u64 reserved;
        __u64 user_data;
};

struct drm_format_modifier_blob {
#define FORMAT_BLOB_CURRENT 1
        /* Version of this blob format */
        __u32 version;

        /* Flags */
        __u32 flags;

        /* Number of fourcc formats supported */
        __u32 count_formats;

        /* Where in this blob the formats exist (in bytes) */
        __u32 formats_offset;

        /* Number of drm_format_modifiers */
        __u32 count_modifiers;

        /* Where in this blob the modifiers exist (in bytes) */
        __u32 modifiers_offset;

        /* __u32 formats[] */
        /* struct drm_format_modifier modifiers[] */
};

struct drm_format_modifier {
        /* Bitmask of formats in get_plane format list this info applies to. The
         * offset allows a sliding window of which 64 formats (bits).
         *
         * Some examples:
         * In today's world with < 65 formats, and formats 0, and 2 are
         * supported
         * 0x0000000000000005
         *                ^-offset = 0, formats = 5
         *
         * If the number formats grew to 128, and formats 98-102 are
         * supported with the modifier:
         *
         * 0x0000007c00000000 0000000000000000
         *                ^
         *                |__offset = 64, formats = 0x7c00000000
         *
         */
        __u64 formats;
        __u32 offset;
        __u32 pad;

        /* The modifier that applies to the >get_plane format list bitmask. */
        __u64 modifier;
};

/**
 * struct drm_mode_create_blob - Create New blob property
 *
 * Create a new 'blob' data property, copying length bytes from data pointer,
 * and returning new blob ID.
 */
struct drm_mode_create_blob {
        /** @data: Pointer to data to copy. */
        __u64 data;
        /** @length: Length of data to copy. */
        __u32 length;
        /** @blob_id: Return: new property ID. */
        __u32 blob_id;
};

/**
 * struct drm_mode_destroy_blob - Destroy user blob
 * @blob_id: blob_id to destroy
 *
 * Destroy a user-created blob property.
 *
 * User-space can release blobs as soon as they do not need to refer to them by
 * their blob object ID.  For instance, if you are using a MODE_ID blob in an
 * atomic commit and you will not make another commit re-using the same ID, you
 * can destroy the blob as soon as the commit has been issued, without waiting
 * for it to complete.
 */
struct drm_mode_destroy_blob {
        __u32 blob_id;
};

/**
 * 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) */
        __u64 object_ids;
        /** @object_count: Number of object ids */
        __u32 object_count;
        /** @flags: flags for new FD (O_CLOEXEC, etc) */
        __u32 flags;

        /** @lessee_id: Return: unique identifier for lessee. */
        __u32 lessee_id;
        /** @fd: Return: file descriptor to new drm_master file */
        __u32 fd;
};

/**
 * struct drm_mode_list_lessees - List lessees
 *
 * List lesses from a drm_master.
 */
struct drm_mode_list_lessees {
        /**
         * @count_lessees: Number of lessees.
         *
         * On input, provides length of the array.
         * On output, provides total number. No
         * more than the input number will be written
         * back, so two calls can be used to get
         * the size and then the data.
         */
        __u32 count_lessees;
        /** @pad: Padding. */
        __u32 pad;

        /**
         * @lessees_ptr: Pointer to lessees.
         *
         * Pointer to __u64 array of lessee ids
         */
        __u64 lessees_ptr;
};

/**
 * struct drm_mode_get_lease - Get Lease
 *
 * Get leased objects.
 */
struct drm_mode_get_lease {
        /**
         * @count_objects: Number of leased objects.
         *
         * On input, provides length of the array.
         * On output, provides total number. No
         * more than the input number will be written
         * back, so two calls can be used to get
         * the size and then the data.
         */
        __u32 count_objects;
        /** @pad: Padding. */
        __u32 pad;

        /**
         * @objects_ptr: Pointer to objects.
         *
         * Pointer to __u32 array of object ids.
         */
        __u64 objects_ptr;
};

/**
 * struct drm_mode_revoke_lease - Revoke lease
 */
struct drm_mode_revoke_lease {
        /** @lessee_id: Unique ID of lessee */
        __u32 lessee_id;
};

/**
 * struct drm_mode_rect - Two dimensional rectangle.
 * @x1: Horizontal starting coordinate (inclusive).
 * @y1: Vertical starting coordinate (inclusive).
 * @x2: Horizontal ending coordinate (exclusive).
 * @y2: Vertical ending coordinate (exclusive).
 *
 * With drm subsystem using struct drm_rect to manage rectangular area this
 * export it to user-space.
 *
 * Currently used by drm_mode_atomic blob property FB_DAMAGE_CLIPS.
 */
struct drm_mode_rect {
        __s32 x1;
        __s32 y1;
        __s32 x2;
        __s32 y2;
};

#if defined(__cplusplus)
}
#endif

#endif