/*
 * Copyright © 1997-2003 by The XFree86 Project, Inc.
 * Copyright © 2007 Dave Airlie
 * Copyright © 2007-2008 Intel Corporation
 *   Jesse Barnes <jesse.barnes@intel.com>
 * Copyright 2005-2006 Luc Verhaegen
 * Copyright (c) 2001, Andy Ritger  aritger@nvidia.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.
 *
 * Except as contained in this notice, the name of the copyright holder(s)
 * and author(s) shall not be used in advertising or otherwise to promote
 * the sale, use or other dealings in this Software without prior written
 * authorization from the copyright holder(s) and author(s).
 */

#include <linux/ctype.h>
#include <linux/export.h>
#include <linux/fb.h> /* for KHZ2PICOS() */
#include <linux/list.h>
#include <linux/list_sort.h>
#include <linux/of.h>

#include <video/of_display_timing.h>
#include <video/of_videomode.h>
#include <video/videomode.h>

#include <drm/drm_crtc.h>
#include <drm/drm_device.h>
#include <drm/drm_edid.h>
#include <drm/drm_modes.h>
#include <drm/drm_print.h>

#include "drm_crtc_internal.h"

/**
 * drm_mode_debug_printmodeline - print a mode to dmesg
 * @mode: mode to print
 *
 * Describe @mode using DRM_DEBUG.
 */
void drm_mode_debug_printmodeline(const struct drm_display_mode *mode)
{
        DRM_DEBUG_KMS("Modeline " DRM_MODE_FMT "\n", DRM_MODE_ARG(mode));
}
EXPORT_SYMBOL(drm_mode_debug_printmodeline);

/**
 * drm_mode_create - create a new display mode
 * @dev: DRM device
 *
 * Create a new, cleared drm_display_mode with kzalloc, allocate an ID for it
 * and return it.
 *
 * Returns:
 * Pointer to new mode on success, NULL on error.
 */
struct drm_display_mode *drm_mode_create(struct drm_device *dev)
{
        struct drm_display_mode *nmode;

        nmode = kzalloc_obj(struct drm_display_mode);
        if (!nmode)
                return NULL;

        return nmode;
}
EXPORT_SYMBOL(drm_mode_create);

/**
 * drm_mode_destroy - remove a mode
 * @dev: DRM device
 * @mode: mode to remove
 *
 * Release @mode's unique ID, then free it @mode structure itself using kfree.
 */
void drm_mode_destroy(struct drm_device *dev, struct drm_display_mode *mode)
{
        if (!mode)
                return;

        kfree(mode);
}
EXPORT_SYMBOL(drm_mode_destroy);

/**
 * drm_mode_probed_add - add a mode to a connector's probed_mode list
 * @connector: connector the new mode
 * @mode: mode data
 *
 * Add @mode to @connector's probed_mode list for later use. This list should
 * then in a second step get filtered and all the modes actually supported by
 * the hardware moved to the @connector's modes list.
 */
void drm_mode_probed_add(struct drm_connector *connector,
                         struct drm_display_mode *mode)
{
        WARN_ON(!mutex_is_locked(&connector->dev->mode_config.mutex));

        list_add_tail(&mode->head, &connector->probed_modes);
}
EXPORT_SYMBOL(drm_mode_probed_add);

enum drm_mode_analog {
        DRM_MODE_ANALOG_NTSC, /* 525 lines, 60Hz */
        DRM_MODE_ANALOG_PAL, /* 625 lines, 50Hz */
};

/*
 * The timings come from:
 * - https://web.archive.org/web/20220406232708/http://www.kolumbus.fi/pami1/video/pal_ntsc.html
 * - https://web.archive.org/web/20220406124914/http://martin.hinner.info/vga/pal.html
 * - https://web.archive.org/web/20220609202433/http://www.batsocks.co.uk/readme/video_timing.htm
 */
#define NTSC_LINE_DURATION_NS           63556U
#define NTSC_LINES_NUMBER               525

#define NTSC_HBLK_DURATION_TYP_NS       10900U
#define NTSC_HBLK_DURATION_MIN_NS       (NTSC_HBLK_DURATION_TYP_NS - 200)
#define NTSC_HBLK_DURATION_MAX_NS       (NTSC_HBLK_DURATION_TYP_NS + 200)

#define NTSC_HACT_DURATION_TYP_NS       (NTSC_LINE_DURATION_NS - NTSC_HBLK_DURATION_TYP_NS)
#define NTSC_HACT_DURATION_MIN_NS       (NTSC_LINE_DURATION_NS - NTSC_HBLK_DURATION_MAX_NS)
#define NTSC_HACT_DURATION_MAX_NS       (NTSC_LINE_DURATION_NS - NTSC_HBLK_DURATION_MIN_NS)

#define NTSC_HFP_DURATION_TYP_NS        1500
#define NTSC_HFP_DURATION_MIN_NS        1270
#define NTSC_HFP_DURATION_MAX_NS        2220

#define NTSC_HSLEN_DURATION_TYP_NS      4700
#define NTSC_HSLEN_DURATION_MIN_NS      (NTSC_HSLEN_DURATION_TYP_NS - 100)
#define NTSC_HSLEN_DURATION_MAX_NS      (NTSC_HSLEN_DURATION_TYP_NS + 100)

#define NTSC_HBP_DURATION_TYP_NS        4700

/*
 * I couldn't find the actual tolerance for the back porch, so let's
 * just reuse the sync length ones.
 */
#define NTSC_HBP_DURATION_MIN_NS        (NTSC_HBP_DURATION_TYP_NS - 100)
#define NTSC_HBP_DURATION_MAX_NS        (NTSC_HBP_DURATION_TYP_NS + 100)

#define PAL_LINE_DURATION_NS            64000U
#define PAL_LINES_NUMBER                625

#define PAL_HACT_DURATION_TYP_NS        51950U
#define PAL_HACT_DURATION_MIN_NS        (PAL_HACT_DURATION_TYP_NS - 100)
#define PAL_HACT_DURATION_MAX_NS        (PAL_HACT_DURATION_TYP_NS + 400)

#define PAL_HBLK_DURATION_TYP_NS        (PAL_LINE_DURATION_NS - PAL_HACT_DURATION_TYP_NS)
#define PAL_HBLK_DURATION_MIN_NS        (PAL_LINE_DURATION_NS - PAL_HACT_DURATION_MAX_NS)
#define PAL_HBLK_DURATION_MAX_NS        (PAL_LINE_DURATION_NS - PAL_HACT_DURATION_MIN_NS)

#define PAL_HFP_DURATION_TYP_NS         1650
#define PAL_HFP_DURATION_MIN_NS         (PAL_HFP_DURATION_TYP_NS - 100)
#define PAL_HFP_DURATION_MAX_NS         (PAL_HFP_DURATION_TYP_NS + 400)

#define PAL_HSLEN_DURATION_TYP_NS       4700
#define PAL_HSLEN_DURATION_MIN_NS       (PAL_HSLEN_DURATION_TYP_NS - 200)
#define PAL_HSLEN_DURATION_MAX_NS       (PAL_HSLEN_DURATION_TYP_NS + 200)

#define PAL_HBP_DURATION_TYP_NS         5700
#define PAL_HBP_DURATION_MIN_NS         (PAL_HBP_DURATION_TYP_NS - 200)
#define PAL_HBP_DURATION_MAX_NS         (PAL_HBP_DURATION_TYP_NS + 200)

struct analog_param_field {
        unsigned int even, odd;
};

#define PARAM_FIELD(_odd, _even)                \
        { .even = _even, .odd = _odd }

struct analog_param_range {
        unsigned int    min, typ, max;
};

#define PARAM_RANGE(_min, _typ, _max)           \
        { .min = _min, .typ = _typ, .max = _max }

struct analog_parameters {
        unsigned int                    num_lines;
        unsigned int                    line_duration_ns;

        struct analog_param_range       hact_ns;
        struct analog_param_range       hfp_ns;
        struct analog_param_range       hslen_ns;
        struct analog_param_range       hbp_ns;
        struct analog_param_range       hblk_ns;

        unsigned int                    bt601_hfp;

        struct analog_param_field       vfp_lines;
        struct analog_param_field       vslen_lines;
        struct analog_param_field       vbp_lines;
};

#define TV_MODE_PARAMETER(_mode, _lines, _line_dur, _hact, _hfp,        \
                          _hslen, _hbp, _hblk, _bt601_hfp, _vfp,        \
                          _vslen, _vbp)                                 \
        [_mode] = {                                                     \
                .num_lines = _lines,                                    \
                .line_duration_ns = _line_dur,                          \
                .hact_ns = _hact,                                       \
                .hfp_ns = _hfp,                                         \
                .hslen_ns = _hslen,                                     \
                .hbp_ns = _hbp,                                         \
                .hblk_ns = _hblk,                                       \
                .bt601_hfp = _bt601_hfp,                                \
                .vfp_lines = _vfp,                                      \
                .vslen_lines = _vslen,                                  \
                .vbp_lines = _vbp,                                      \
        }

static const struct analog_parameters tv_modes_parameters[] = {
        TV_MODE_PARAMETER(DRM_MODE_ANALOG_NTSC,
                          NTSC_LINES_NUMBER,
                          NTSC_LINE_DURATION_NS,
                          PARAM_RANGE(NTSC_HACT_DURATION_MIN_NS,
                                      NTSC_HACT_DURATION_TYP_NS,
                                      NTSC_HACT_DURATION_MAX_NS),
                          PARAM_RANGE(NTSC_HFP_DURATION_MIN_NS,
                                      NTSC_HFP_DURATION_TYP_NS,
                                      NTSC_HFP_DURATION_MAX_NS),
                          PARAM_RANGE(NTSC_HSLEN_DURATION_MIN_NS,
                                      NTSC_HSLEN_DURATION_TYP_NS,
                                      NTSC_HSLEN_DURATION_MAX_NS),
                          PARAM_RANGE(NTSC_HBP_DURATION_MIN_NS,
                                      NTSC_HBP_DURATION_TYP_NS,
                                      NTSC_HBP_DURATION_MAX_NS),
                          PARAM_RANGE(NTSC_HBLK_DURATION_MIN_NS,
                                      NTSC_HBLK_DURATION_TYP_NS,
                                      NTSC_HBLK_DURATION_MAX_NS),
                          16,
                          PARAM_FIELD(3, 3),
                          PARAM_FIELD(3, 3),
                          PARAM_FIELD(16, 17)),
        TV_MODE_PARAMETER(DRM_MODE_ANALOG_PAL,
                          PAL_LINES_NUMBER,
                          PAL_LINE_DURATION_NS,
                          PARAM_RANGE(PAL_HACT_DURATION_MIN_NS,
                                      PAL_HACT_DURATION_TYP_NS,
                                      PAL_HACT_DURATION_MAX_NS),
                          PARAM_RANGE(PAL_HFP_DURATION_MIN_NS,
                                      PAL_HFP_DURATION_TYP_NS,
                                      PAL_HFP_DURATION_MAX_NS),
                          PARAM_RANGE(PAL_HSLEN_DURATION_MIN_NS,
                                      PAL_HSLEN_DURATION_TYP_NS,
                                      PAL_HSLEN_DURATION_MAX_NS),
                          PARAM_RANGE(PAL_HBP_DURATION_MIN_NS,
                                      PAL_HBP_DURATION_TYP_NS,
                                      PAL_HBP_DURATION_MAX_NS),
                          PARAM_RANGE(PAL_HBLK_DURATION_MIN_NS,
                                      PAL_HBLK_DURATION_TYP_NS,
                                      PAL_HBLK_DURATION_MAX_NS),
                          12,

                          /*
                           * The front porch is actually 6 short sync
                           * pulses for the even field, and 5 for the
                           * odd field. Each sync takes half a life so
                           * the odd field front porch is shorter by
                           * half a line.
                           *
                           * In progressive, we're supposed to use 6
                           * pulses, so we're fine there
                           */
                          PARAM_FIELD(3, 2),

                          /*
                           * The vsync length is 5 long sync pulses,
                           * each field taking half a line. We're
                           * shorter for both fields by half a line.
                           *
                           * In progressive, we're supposed to use 5
                           * pulses, so we're off by half
                           * a line.
                           *
                           * In interlace, we're now off by half a line
                           * for the even field and one line for the odd
                           * field.
                           */
                          PARAM_FIELD(3, 3),

                          /*
                           * The back porch starts with post-equalizing
                           * pulses, consisting in 5 short sync pulses
                           * for the even field, 4 for the odd field. In
                           * progressive, it's 5 short syncs.
                           *
                           * In progressive, we thus have 2.5 lines,
                           * plus the 0.5 line we were missing
                           * previously, so we should use 3 lines.
                           *
                           * In interlace, the even field is in the
                           * exact same case than progressive. For the
                           * odd field, we should be using 2 lines but
                           * we're one line short, so we'll make up for
                           * it here by using 3.
                           *
                           * The entire blanking area is supposed to
                           * take 25 lines, so we also need to account
                           * for the rest of the blanking area that
                           * can't be in either the front porch or sync
                           * period.
                           */
                          PARAM_FIELD(19, 20)),
};

static int fill_analog_mode(struct drm_device *dev,
                            struct drm_display_mode *mode,
                            const struct analog_parameters *params,
                            unsigned long pixel_clock_hz,
                            unsigned int hactive,
                            unsigned int vactive,
                            bool interlace)
{
        unsigned long pixel_duration_ns = NSEC_PER_SEC / pixel_clock_hz;
        unsigned int htotal, vtotal;
        unsigned int max_hact, hact_duration_ns;
        unsigned int hblk, hblk_duration_ns;
        unsigned int hfp, hfp_duration_ns;
        unsigned int hslen, hslen_duration_ns;
        unsigned int hbp, hbp_duration_ns;
        unsigned int porches, porches_duration_ns;
        unsigned int vfp, vfp_min;
        unsigned int vbp, vbp_min;
        unsigned int vslen;
        bool bt601 = false;
        int porches_rem;
        u64 result;

        drm_dbg_kms(dev,
                    "Generating a %ux%u%c, %u-line mode with a %lu kHz clock\n",
                    hactive, vactive,
                    interlace ? 'i' : 'p',
                    params->num_lines,
                    pixel_clock_hz / 1000);

        max_hact = params->hact_ns.max / pixel_duration_ns;
        if (pixel_clock_hz == 13500000 && hactive > max_hact && hactive <= 720) {
                drm_dbg_kms(dev, "Trying to generate a BT.601 mode. Disabling checks.\n");
                bt601 = true;
        }

        /*
         * Our pixel duration is going to be round down by the division,
         * so rounding up is probably going to introduce even more
         * deviation.
         */
        result = (u64)params->line_duration_ns * pixel_clock_hz;
        do_div(result, NSEC_PER_SEC);
        htotal = result;

        drm_dbg_kms(dev, "Total Horizontal Number of Pixels: %u\n", htotal);

        hact_duration_ns = hactive * pixel_duration_ns;
        if (!bt601 &&
            (hact_duration_ns < params->hact_ns.min ||
             hact_duration_ns > params->hact_ns.max)) {
                drm_err(dev, "Invalid horizontal active area duration: %uns (min: %u, max %u)\n",
                        hact_duration_ns, params->hact_ns.min, params->hact_ns.max);
                return -EINVAL;
        }

        hblk = htotal - hactive;
        drm_dbg_kms(dev, "Horizontal Blanking Period: %u\n", hblk);

        hblk_duration_ns = hblk * pixel_duration_ns;
        if (!bt601 &&
            (hblk_duration_ns < params->hblk_ns.min ||
             hblk_duration_ns > params->hblk_ns.max)) {
                drm_err(dev, "Invalid horizontal blanking duration: %uns (min: %u, max %u)\n",
                        hblk_duration_ns, params->hblk_ns.min, params->hblk_ns.max);
                return -EINVAL;
        }

        hslen = DIV_ROUND_UP(params->hslen_ns.typ, pixel_duration_ns);
        drm_dbg_kms(dev, "Horizontal Sync Period: %u\n", hslen);

        hslen_duration_ns = hslen * pixel_duration_ns;
        if (!bt601 &&
            (hslen_duration_ns < params->hslen_ns.min ||
             hslen_duration_ns > params->hslen_ns.max)) {
                drm_err(dev, "Invalid horizontal sync duration: %uns (min: %u, max %u)\n",
                        hslen_duration_ns, params->hslen_ns.min, params->hslen_ns.max);
                return -EINVAL;
        }

        porches = hblk - hslen;
        drm_dbg_kms(dev, "Remaining horizontal pixels for both porches: %u\n", porches);

        porches_duration_ns = porches * pixel_duration_ns;
        if (!bt601 &&
            (porches_duration_ns > (params->hfp_ns.max + params->hbp_ns.max) ||
             porches_duration_ns < (params->hfp_ns.min + params->hbp_ns.min))) {
                drm_err(dev, "Invalid horizontal porches duration: %uns\n",
                        porches_duration_ns);
                return -EINVAL;
        }

        if (bt601) {
                hfp = params->bt601_hfp;
        } else {
                unsigned int hfp_min = DIV_ROUND_UP(params->hfp_ns.min,
                                                    pixel_duration_ns);
                unsigned int hbp_min = DIV_ROUND_UP(params->hbp_ns.min,
                                                    pixel_duration_ns);
                int porches_rem = porches - hfp_min - hbp_min;

                hfp = hfp_min + DIV_ROUND_UP(porches_rem, 2);
        }

        drm_dbg_kms(dev, "Horizontal Front Porch: %u\n", hfp);

        hfp_duration_ns = hfp * pixel_duration_ns;
        if (!bt601 &&
            (hfp_duration_ns < params->hfp_ns.min ||
             hfp_duration_ns > params->hfp_ns.max)) {
                drm_err(dev, "Invalid horizontal front porch duration: %uns (min: %u, max %u)\n",
                        hfp_duration_ns, params->hfp_ns.min, params->hfp_ns.max);
                return -EINVAL;
        }

        hbp = porches - hfp;
        drm_dbg_kms(dev, "Horizontal Back Porch: %u\n", hbp);

        hbp_duration_ns = hbp * pixel_duration_ns;
        if (!bt601 &&
            (hbp_duration_ns < params->hbp_ns.min ||
             hbp_duration_ns > params->hbp_ns.max)) {
                drm_err(dev, "Invalid horizontal back porch duration: %uns (min: %u, max %u)\n",
                        hbp_duration_ns, params->hbp_ns.min, params->hbp_ns.max);
                return -EINVAL;
        }

        if (htotal != (hactive + hfp + hslen + hbp))
                return -EINVAL;

        mode->clock = pixel_clock_hz / 1000;
        mode->hdisplay = hactive;
        mode->hsync_start = mode->hdisplay + hfp;
        mode->hsync_end = mode->hsync_start + hslen;
        mode->htotal = mode->hsync_end + hbp;

        if (interlace) {
                vfp_min = params->vfp_lines.even + params->vfp_lines.odd;
                vbp_min = params->vbp_lines.even + params->vbp_lines.odd;
                vslen = params->vslen_lines.even + params->vslen_lines.odd;
        } else {
                /*
                 * By convention, NTSC (aka 525/60) systems start with
                 * the even field, but PAL (aka 625/50) systems start
                 * with the odd one.
                 *
                 * PAL systems also have asymmetric timings between the
                 * even and odd field, while NTSC is symmetric.
                 *
                 * Moreover, if we want to create a progressive mode for
                 * PAL, we need to use the odd field timings.
                 *
                 * Since odd == even for NTSC, we can just use the odd
                 * one all the time to simplify the code a bit.
                 */
                vfp_min = params->vfp_lines.odd;
                vbp_min = params->vbp_lines.odd;
                vslen = params->vslen_lines.odd;
        }

        drm_dbg_kms(dev, "Vertical Sync Period: %u\n", vslen);

        porches = params->num_lines - vactive - vslen;
        drm_dbg_kms(dev, "Remaining vertical pixels for both porches: %u\n", porches);

        porches_rem = porches - vfp_min - vbp_min;
        vfp = vfp_min + (porches_rem / 2);
        drm_dbg_kms(dev, "Vertical Front Porch: %u\n", vfp);

        vbp = porches - vfp;
        drm_dbg_kms(dev, "Vertical Back Porch: %u\n", vbp);

        vtotal = vactive + vfp + vslen + vbp;
        if (params->num_lines != vtotal) {
                drm_err(dev, "Invalid vertical total: %upx (expected %upx)\n",
                        vtotal, params->num_lines);
                return -EINVAL;
        }

        mode->vdisplay = vactive;
        mode->vsync_start = mode->vdisplay + vfp;
        mode->vsync_end = mode->vsync_start + vslen;
        mode->vtotal = mode->vsync_end + vbp;

        if (mode->vtotal != params->num_lines)
                return -EINVAL;

        mode->type = DRM_MODE_TYPE_DRIVER;
        mode->flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC;
        if (interlace)
                mode->flags |= DRM_MODE_FLAG_INTERLACE;

        drm_mode_set_name(mode);

        drm_dbg_kms(dev, "Generated mode " DRM_MODE_FMT "\n", DRM_MODE_ARG(mode));

        return 0;
}

/**
 * drm_analog_tv_mode - create a display mode for an analog TV
 * @dev: drm device
 * @tv_mode: TV Mode standard to create a mode for. See DRM_MODE_TV_MODE_*.
 * @pixel_clock_hz: Pixel Clock Frequency, in Hertz
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @interlace: whether to compute an interlaced mode
 *
 * This function creates a struct drm_display_mode instance suited for
 * an analog TV output, for one of the usual analog TV modes. Where
 * this is DRM_MODE_TV_MODE_MONOCHROME, a 625-line mode will be created.
 *
 * Note that @hdisplay is larger than the usual constraints for the PAL
 * and NTSC timings, and we'll choose to ignore most timings constraints
 * to reach those resolutions.
 *
 * Returns:
 * A pointer to the mode, allocated with drm_mode_create(). Returns NULL
 * on error.
 */
struct drm_display_mode *drm_analog_tv_mode(struct drm_device *dev,
                                            enum drm_connector_tv_mode tv_mode,
                                            unsigned long pixel_clock_hz,
                                            unsigned int hdisplay,
                                            unsigned int vdisplay,
                                            bool interlace)
{
        struct drm_display_mode *mode;
        enum drm_mode_analog analog;
        int ret;

        switch (tv_mode) {
        case DRM_MODE_TV_MODE_NTSC:
                fallthrough;
        case DRM_MODE_TV_MODE_NTSC_443:
                fallthrough;
        case DRM_MODE_TV_MODE_NTSC_J:
                fallthrough;
        case DRM_MODE_TV_MODE_PAL_M:
                analog = DRM_MODE_ANALOG_NTSC;
                break;

        case DRM_MODE_TV_MODE_PAL:
                fallthrough;
        case DRM_MODE_TV_MODE_PAL_N:
                fallthrough;
        case DRM_MODE_TV_MODE_SECAM:
                fallthrough;
        case DRM_MODE_TV_MODE_MONOCHROME:
                analog = DRM_MODE_ANALOG_PAL;
                break;

        default:
                return NULL;
        }

        mode = drm_mode_create(dev);
        if (!mode)
                return NULL;

        ret = fill_analog_mode(dev, mode,
                               &tv_modes_parameters[analog],
                               pixel_clock_hz, hdisplay, vdisplay, interlace);
        if (ret)
                goto err_free_mode;

        return mode;

err_free_mode:
        drm_mode_destroy(dev, mode);
        return NULL;
}
EXPORT_SYMBOL(drm_analog_tv_mode);

/**
 * drm_cvt_mode -create a modeline based on the CVT algorithm
 * @dev: drm device
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @vrefresh: vrefresh rate
 * @reduced: whether to use reduced blanking
 * @interlaced: whether to compute an interlaced mode
 * @margins: whether to add margins (borders)
 *
 * This function is called to generate the modeline based on CVT algorithm
 * according to the hdisplay, vdisplay, vrefresh.
 * It is based from the VESA(TM) Coordinated Video Timing Generator by
 * Graham Loveridge April 9, 2003 available at
 * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls
 *
 * And it is copied from xf86CVTmode in xserver/hw/xfree86/modes/xf86cvt.c.
 * What I have done is to translate it by using integer calculation.
 *
 * Returns:
 * The modeline based on the CVT algorithm stored in a drm_display_mode object.
 * The display mode object is allocated with drm_mode_create(). Returns NULL
 * when no mode could be allocated.
 */
struct drm_display_mode *drm_cvt_mode(struct drm_device *dev, int hdisplay,
                                      int vdisplay, int vrefresh,
                                      bool reduced, bool interlaced, bool margins)
{
#define HV_FACTOR                       1000
        /* 1) top/bottom margin size (% of height) - default: 1.8, */
#define CVT_MARGIN_PERCENTAGE           18
        /* 2) character cell horizontal granularity (pixels) - default 8 */
#define CVT_H_GRANULARITY               8
        /* 3) Minimum vertical porch (lines) - default 3 */
#define CVT_MIN_V_PORCH                 3
        /* 4) Minimum number of vertical back porch lines - default 6 */
#define CVT_MIN_V_BPORCH                6
        /* Pixel Clock step (kHz) */
#define CVT_CLOCK_STEP                  250
        struct drm_display_mode *drm_mode;
        unsigned int vfieldrate, hperiod;
        int hdisplay_rnd, hmargin, vdisplay_rnd, vmargin, vsync;
        int interlace;
        u64 tmp;

        if (!hdisplay || !vdisplay)
                return NULL;

        /* allocate the drm_display_mode structure. If failure, we will
         * return directly
         */
        drm_mode = drm_mode_create(dev);
        if (!drm_mode)
                return NULL;

        /* the CVT default refresh rate is 60Hz */
        if (!vrefresh)
                vrefresh = 60;

        /* the required field fresh rate */
        if (interlaced)
                vfieldrate = vrefresh * 2;
        else
                vfieldrate = vrefresh;

        /* horizontal pixels */
        hdisplay_rnd = hdisplay - (hdisplay % CVT_H_GRANULARITY);

        /* determine the left&right borders */
        hmargin = 0;
        if (margins) {
                hmargin = hdisplay_rnd * CVT_MARGIN_PERCENTAGE / 1000;
                hmargin -= hmargin % CVT_H_GRANULARITY;
        }
        /* find the total active pixels */
        drm_mode->hdisplay = hdisplay_rnd + 2 * hmargin;

        /* find the number of lines per field */
        if (interlaced)
                vdisplay_rnd = vdisplay / 2;
        else
                vdisplay_rnd = vdisplay;

        /* find the top & bottom borders */
        vmargin = 0;
        if (margins)
                vmargin = vdisplay_rnd * CVT_MARGIN_PERCENTAGE / 1000;

        drm_mode->vdisplay = vdisplay + 2 * vmargin;

        /* Interlaced */
        if (interlaced)
                interlace = 1;
        else
                interlace = 0;

        /* Determine VSync Width from aspect ratio */
        if (!(vdisplay % 3) && ((vdisplay * 4 / 3) == hdisplay))
                vsync = 4;
        else if (!(vdisplay % 9) && ((vdisplay * 16 / 9) == hdisplay))
                vsync = 5;
        else if (!(vdisplay % 10) && ((vdisplay * 16 / 10) == hdisplay))
                vsync = 6;
        else if (!(vdisplay % 4) && ((vdisplay * 5 / 4) == hdisplay))
                vsync = 7;
        else if (!(vdisplay % 9) && ((vdisplay * 15 / 9) == hdisplay))
                vsync = 7;
        else /* custom */
                vsync = 10;

        if (!reduced) {
                /* simplify the GTF calculation */
                /* 4) Minimum time of vertical sync + back porch interval (µs)
                 * default 550.0
                 */
                int tmp1, tmp2;
#define CVT_MIN_VSYNC_BP        550
                /* 3) Nominal HSync width (% of line period) - default 8 */
#define CVT_HSYNC_PERCENTAGE    8
                unsigned int hblank_percentage;
                int vsyncandback_porch, __maybe_unused vback_porch, hblank;

                /* estimated the horizontal period */
                tmp1 = HV_FACTOR * 1000000  -
                                CVT_MIN_VSYNC_BP * HV_FACTOR * vfieldrate;
                tmp2 = (vdisplay_rnd + 2 * vmargin + CVT_MIN_V_PORCH) * 2 +
                                interlace;
                hperiod = tmp1 * 2 / (tmp2 * vfieldrate);

                tmp1 = CVT_MIN_VSYNC_BP * HV_FACTOR / hperiod + 1;
                /* 9. Find number of lines in sync + backporch */
                if (tmp1 < (vsync + CVT_MIN_V_PORCH))
                        vsyncandback_porch = vsync + CVT_MIN_V_PORCH;
                else
                        vsyncandback_porch = tmp1;
                /* 10. Find number of lines in back porch */
                vback_porch = vsyncandback_porch - vsync;
                drm_mode->vtotal = vdisplay_rnd + 2 * vmargin +
                                vsyncandback_porch + CVT_MIN_V_PORCH;
                /* 5) Definition of Horizontal blanking time limitation */
                /* Gradient (%/kHz) - default 600 */
#define CVT_M_FACTOR    600
                /* Offset (%) - default 40 */
#define CVT_C_FACTOR    40
                /* Blanking time scaling factor - default 128 */
#define CVT_K_FACTOR    128
                /* Scaling factor weighting - default 20 */
#define CVT_J_FACTOR    20
#define CVT_M_PRIME     (CVT_M_FACTOR * CVT_K_FACTOR / 256)
#define CVT_C_PRIME     ((CVT_C_FACTOR - CVT_J_FACTOR) * CVT_K_FACTOR / 256 + \
                         CVT_J_FACTOR)
                /* 12. Find ideal blanking duty cycle from formula */
                hblank_percentage = CVT_C_PRIME * HV_FACTOR - CVT_M_PRIME *
                                        hperiod / 1000;
                /* 13. Blanking time */
                if (hblank_percentage < 20 * HV_FACTOR)
                        hblank_percentage = 20 * HV_FACTOR;
                hblank = drm_mode->hdisplay * hblank_percentage /
                         (100 * HV_FACTOR - hblank_percentage);
                hblank -= hblank % (2 * CVT_H_GRANULARITY);
                /* 14. find the total pixels per line */
                drm_mode->htotal = drm_mode->hdisplay + hblank;
                drm_mode->hsync_end = drm_mode->hdisplay + hblank / 2;
                drm_mode->hsync_start = drm_mode->hsync_end -
                        (drm_mode->htotal * CVT_HSYNC_PERCENTAGE) / 100;
                drm_mode->hsync_start += CVT_H_GRANULARITY -
                        drm_mode->hsync_start % CVT_H_GRANULARITY;
                /* fill the Vsync values */
                drm_mode->vsync_start = drm_mode->vdisplay + CVT_MIN_V_PORCH;
                drm_mode->vsync_end = drm_mode->vsync_start + vsync;
        } else {
                /* Reduced blanking */
                /* Minimum vertical blanking interval time (µs)- default 460 */
#define CVT_RB_MIN_VBLANK       460
                /* Fixed number of clocks for horizontal sync */
#define CVT_RB_H_SYNC           32
                /* Fixed number of clocks for horizontal blanking */
#define CVT_RB_H_BLANK          160
                /* Fixed number of lines for vertical front porch - default 3*/
#define CVT_RB_VFPORCH          3
                int vbilines;
                int tmp1, tmp2;
                /* 8. Estimate Horizontal period. */
                tmp1 = HV_FACTOR * 1000000 -
                        CVT_RB_MIN_VBLANK * HV_FACTOR * vfieldrate;
                tmp2 = vdisplay_rnd + 2 * vmargin;
                hperiod = tmp1 / (tmp2 * vfieldrate);
                /* 9. Find number of lines in vertical blanking */
                vbilines = CVT_RB_MIN_VBLANK * HV_FACTOR / hperiod + 1;
                /* 10. Check if vertical blanking is sufficient */
                if (vbilines < (CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH))
                        vbilines = CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH;
                /* 11. Find total number of lines in vertical field */
                drm_mode->vtotal = vdisplay_rnd + 2 * vmargin + vbilines;
                /* 12. Find total number of pixels in a line */
                drm_mode->htotal = drm_mode->hdisplay + CVT_RB_H_BLANK;
                /* Fill in HSync values */
                drm_mode->hsync_end = drm_mode->hdisplay + CVT_RB_H_BLANK / 2;
                drm_mode->hsync_start = drm_mode->hsync_end - CVT_RB_H_SYNC;
                /* Fill in VSync values */
                drm_mode->vsync_start = drm_mode->vdisplay + CVT_RB_VFPORCH;
                drm_mode->vsync_end = drm_mode->vsync_start + vsync;
        }
        /* 15/13. Find pixel clock frequency (kHz for xf86) */
        tmp = drm_mode->htotal; /* perform intermediate calcs in u64 */
        tmp *= HV_FACTOR * 1000;
        do_div(tmp, hperiod);
        tmp -= drm_mode->clock % CVT_CLOCK_STEP;
        drm_mode->clock = tmp;
        /* 18/16. Find actual vertical frame frequency */
        /* ignore - just set the mode flag for interlaced */
        if (interlaced) {
                drm_mode->vtotal *= 2;
                drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
        }
        /* Fill the mode line name */
        drm_mode_set_name(drm_mode);
        if (reduced)
                drm_mode->flags |= (DRM_MODE_FLAG_PHSYNC |
                                        DRM_MODE_FLAG_NVSYNC);
        else
                drm_mode->flags |= (DRM_MODE_FLAG_PVSYNC |
                                        DRM_MODE_FLAG_NHSYNC);

        return drm_mode;
}
EXPORT_SYMBOL(drm_cvt_mode);

/**
 * drm_gtf_mode_complex - create the modeline based on the full GTF algorithm
 * @dev: drm device
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @vrefresh: vrefresh rate.
 * @interlaced: whether to compute an interlaced mode
 * @margins: desired margin (borders) size
 * @GTF_M: extended GTF formula parameters
 * @GTF_2C: extended GTF formula parameters
 * @GTF_K: extended GTF formula parameters
 * @GTF_2J: extended GTF formula parameters
 *
 * GTF feature blocks specify C and J in multiples of 0.5, so we pass them
 * in here multiplied by two.  For a C of 40, pass in 80.
 *
 * Returns:
 * The modeline based on the full GTF algorithm stored in a drm_display_mode object.
 * The display mode object is allocated with drm_mode_create(). Returns NULL
 * when no mode could be allocated.
 */
struct drm_display_mode *
drm_gtf_mode_complex(struct drm_device *dev, int hdisplay, int vdisplay,
                     int vrefresh, bool interlaced, int margins,
                     int GTF_M, int GTF_2C, int GTF_K, int GTF_2J)
{       /* 1) top/bottom margin size (% of height) - default: 1.8, */
#define GTF_MARGIN_PERCENTAGE           18
        /* 2) character cell horizontal granularity (pixels) - default 8 */
#define GTF_CELL_GRAN                   8
        /* 3) Minimum vertical porch (lines) - default 3 */
#define GTF_MIN_V_PORCH                 1
        /* width of vsync in lines */
#define V_SYNC_RQD                      3
        /* width of hsync as % of total line */
#define H_SYNC_PERCENT                  8
        /* min time of vsync + back porch (microsec) */
#define MIN_VSYNC_PLUS_BP               550
        /* C' and M' are part of the Blanking Duty Cycle computation */
#define GTF_C_PRIME     ((((GTF_2C - GTF_2J) * GTF_K / 256) + GTF_2J) / 2)
#define GTF_M_PRIME     (GTF_K * GTF_M / 256)
        struct drm_display_mode *drm_mode;
        unsigned int hdisplay_rnd, vdisplay_rnd, vfieldrate_rqd;
        int top_margin, bottom_margin;
        int interlace;
        unsigned int hfreq_est;
        int vsync_plus_bp, __maybe_unused vback_porch;
        unsigned int vtotal_lines, __maybe_unused vfieldrate_est;
        unsigned int __maybe_unused hperiod;
        unsigned int vfield_rate, __maybe_unused vframe_rate;
        int left_margin, right_margin;
        unsigned int total_active_pixels, ideal_duty_cycle;
        unsigned int hblank, total_pixels, pixel_freq;
        int hsync, hfront_porch, vodd_front_porch_lines;
        unsigned int tmp1, tmp2;

        if (!hdisplay || !vdisplay)
                return NULL;

        drm_mode = drm_mode_create(dev);
        if (!drm_mode)
                return NULL;

        /* 1. In order to give correct results, the number of horizontal
         * pixels requested is first processed to ensure that it is divisible
         * by the character size, by rounding it to the nearest character
         * cell boundary:
         */
        hdisplay_rnd = (hdisplay + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN;
        hdisplay_rnd = hdisplay_rnd * GTF_CELL_GRAN;

        /* 2. If interlace is requested, the number of vertical lines assumed
         * by the calculation must be halved, as the computation calculates
         * the number of vertical lines per field.
         */
        if (interlaced)
                vdisplay_rnd = vdisplay / 2;
        else
                vdisplay_rnd = vdisplay;

        /* 3. Find the frame rate required: */
        if (interlaced)
                vfieldrate_rqd = vrefresh * 2;
        else
                vfieldrate_rqd = vrefresh;

        /* 4. Find number of lines in Top margin: */
        top_margin = 0;
        if (margins)
                top_margin = (vdisplay_rnd * GTF_MARGIN_PERCENTAGE + 500) /
                                1000;
        /* 5. Find number of lines in bottom margin: */
        bottom_margin = top_margin;

        /* 6. If interlace is required, then set variable interlace: */
        if (interlaced)
                interlace = 1;
        else
                interlace = 0;

        /* 7. Estimate the Horizontal frequency */
        {
                tmp1 = (1000000  - MIN_VSYNC_PLUS_BP * vfieldrate_rqd) / 500;
                tmp2 = (vdisplay_rnd + 2 * top_margin + GTF_MIN_V_PORCH) *
                                2 + interlace;
                hfreq_est = (tmp2 * 1000 * vfieldrate_rqd) / tmp1;
        }

        /* 8. Find the number of lines in V sync + back porch */
        /* [V SYNC+BP] = RINT(([MIN VSYNC+BP] * hfreq_est / 1000000)) */
        vsync_plus_bp = MIN_VSYNC_PLUS_BP * hfreq_est / 1000;
        vsync_plus_bp = (vsync_plus_bp + 500) / 1000;
        /*  9. Find the number of lines in V back porch alone: */
        vback_porch = vsync_plus_bp - V_SYNC_RQD;
        /*  10. Find the total number of lines in Vertical field period: */
        vtotal_lines = vdisplay_rnd + top_margin + bottom_margin +
                        vsync_plus_bp + GTF_MIN_V_PORCH;
        /*  11. Estimate the Vertical field frequency: */
        vfieldrate_est = hfreq_est / vtotal_lines;
        /*  12. Find the actual horizontal period: */
        hperiod = 1000000 / (vfieldrate_rqd * vtotal_lines);

        /*  13. Find the actual Vertical field frequency: */
        vfield_rate = hfreq_est / vtotal_lines;
        /*  14. Find the Vertical frame frequency: */
        if (interlaced)
                vframe_rate = vfield_rate / 2;
        else
                vframe_rate = vfield_rate;
        /*  15. Find number of pixels in left margin: */
        if (margins)
                left_margin = (hdisplay_rnd * GTF_MARGIN_PERCENTAGE + 500) /
                                1000;
        else
                left_margin = 0;

        /* 16.Find number of pixels in right margin: */
        right_margin = left_margin;
        /* 17.Find total number of active pixels in image and left and right */
        total_active_pixels = hdisplay_rnd + left_margin + right_margin;
        /* 18.Find the ideal blanking duty cycle from blanking duty cycle */
        ideal_duty_cycle = GTF_C_PRIME * 1000 -
                                (GTF_M_PRIME * 1000000 / hfreq_est);
        /* 19.Find the number of pixels in the blanking time to the nearest
         * double character cell: */
        hblank = total_active_pixels * ideal_duty_cycle /
                        (100000 - ideal_duty_cycle);
        hblank = (hblank + GTF_CELL_GRAN) / (2 * GTF_CELL_GRAN);
        hblank = hblank * 2 * GTF_CELL_GRAN;
        /* 20.Find total number of pixels: */
        total_pixels = total_active_pixels + hblank;
        /* 21.Find pixel clock frequency: */
        pixel_freq = total_pixels * hfreq_est / 1000;
        /* Stage 1 computations are now complete; I should really pass
         * the results to another function and do the Stage 2 computations,
         * but I only need a few more values so I'll just append the
         * computations here for now */
        /* 17. Find the number of pixels in the horizontal sync period: */
        hsync = H_SYNC_PERCENT * total_pixels / 100;
        hsync = (hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN;
        hsync = hsync * GTF_CELL_GRAN;
        /* 18. Find the number of pixels in horizontal front porch period */
        hfront_porch = hblank / 2 - hsync;
        /*  36. Find the number of lines in the odd front porch period: */
        vodd_front_porch_lines = GTF_MIN_V_PORCH ;

        /* finally, pack the results in the mode struct */
        drm_mode->hdisplay = hdisplay_rnd;
        drm_mode->hsync_start = hdisplay_rnd + hfront_porch;
        drm_mode->hsync_end = drm_mode->hsync_start + hsync;
        drm_mode->htotal = total_pixels;
        drm_mode->vdisplay = vdisplay_rnd;
        drm_mode->vsync_start = vdisplay_rnd + vodd_front_porch_lines;
        drm_mode->vsync_end = drm_mode->vsync_start + V_SYNC_RQD;
        drm_mode->vtotal = vtotal_lines;

        drm_mode->clock = pixel_freq;

        if (interlaced) {
                drm_mode->vtotal *= 2;
                drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
        }

        drm_mode_set_name(drm_mode);
        if (GTF_M == 600 && GTF_2C == 80 && GTF_K == 128 && GTF_2J == 40)
                drm_mode->flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC;
        else
                drm_mode->flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC;

        return drm_mode;
}
EXPORT_SYMBOL(drm_gtf_mode_complex);

/**
 * drm_gtf_mode - create the modeline based on the GTF algorithm
 * @dev: drm device
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @vrefresh: vrefresh rate.
 * @interlaced: whether to compute an interlaced mode
 * @margins: desired margin (borders) size
 *
 * return the modeline based on GTF algorithm
 *
 * This function is to create the modeline based on the GTF algorithm.
 * Generalized Timing Formula is derived from:
 *
 *      GTF Spreadsheet by Andy Morrish (1/5/97)
 *      available at https://www.vesa.org
 *
 * And it is copied from the file of xserver/hw/xfree86/modes/xf86gtf.c.
 * What I have done is to translate it by using integer calculation.
 * I also refer to the function of fb_get_mode in the file of
 * drivers/video/fbmon.c
 *
 * Standard GTF parameters::
 *
 *     M = 600
 *     C = 40
 *     K = 128
 *     J = 20
 *
 * Returns:
 * The modeline based on the GTF algorithm stored in a drm_display_mode object.
 * The display mode object is allocated with drm_mode_create(). Returns NULL
 * when no mode could be allocated.
 */
struct drm_display_mode *
drm_gtf_mode(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh,
             bool interlaced, int margins)
{
        return drm_gtf_mode_complex(dev, hdisplay, vdisplay, vrefresh,
                                    interlaced, margins,
                                    600, 40 * 2, 128, 20 * 2);
}
EXPORT_SYMBOL(drm_gtf_mode);

#ifdef CONFIG_VIDEOMODE_HELPERS
/**
 * drm_display_mode_from_videomode - fill in @dmode using @vm,
 * @vm: videomode structure to use as source
 * @dmode: drm_display_mode structure to use as destination
 *
 * Fills out @dmode using the display mode specified in @vm.
 */
void drm_display_mode_from_videomode(const struct videomode *vm,
                                     struct drm_display_mode *dmode)
{
        dmode->hdisplay = vm->hactive;
        dmode->hsync_start = dmode->hdisplay + vm->hfront_porch;
        dmode->hsync_end = dmode->hsync_start + vm->hsync_len;
        dmode->htotal = dmode->hsync_end + vm->hback_porch;

        dmode->vdisplay = vm->vactive;
        dmode->vsync_start = dmode->vdisplay + vm->vfront_porch;
        dmode->vsync_end = dmode->vsync_start + vm->vsync_len;
        dmode->vtotal = dmode->vsync_end + vm->vback_porch;

        dmode->clock = vm->pixelclock / 1000;

        dmode->flags = 0;
        if (vm->flags & DISPLAY_FLAGS_HSYNC_HIGH)
                dmode->flags |= DRM_MODE_FLAG_PHSYNC;
        else if (vm->flags & DISPLAY_FLAGS_HSYNC_LOW)
                dmode->flags |= DRM_MODE_FLAG_NHSYNC;
        if (vm->flags & DISPLAY_FLAGS_VSYNC_HIGH)
                dmode->flags |= DRM_MODE_FLAG_PVSYNC;
        else if (vm->flags & DISPLAY_FLAGS_VSYNC_LOW)
                dmode->flags |= DRM_MODE_FLAG_NVSYNC;
        if (vm->flags & DISPLAY_FLAGS_INTERLACED)
                dmode->flags |= DRM_MODE_FLAG_INTERLACE;
        if (vm->flags & DISPLAY_FLAGS_DOUBLESCAN)
                dmode->flags |= DRM_MODE_FLAG_DBLSCAN;
        if (vm->flags & DISPLAY_FLAGS_DOUBLECLK)
                dmode->flags |= DRM_MODE_FLAG_DBLCLK;
        drm_mode_set_name(dmode);
}
EXPORT_SYMBOL_GPL(drm_display_mode_from_videomode);

/**
 * drm_display_mode_to_videomode - fill in @vm using @dmode,
 * @dmode: drm_display_mode structure to use as source
 * @vm: videomode structure to use as destination
 *
 * Fills out @vm using the display mode specified in @dmode.
 */
void drm_display_mode_to_videomode(const struct drm_display_mode *dmode,
                                   struct videomode *vm)
{
        vm->hactive = dmode->hdisplay;
        vm->hfront_porch = dmode->hsync_start - dmode->hdisplay;
        vm->hsync_len = dmode->hsync_end - dmode->hsync_start;
        vm->hback_porch = dmode->htotal - dmode->hsync_end;

        vm->vactive = dmode->vdisplay;
        vm->vfront_porch = dmode->vsync_start - dmode->vdisplay;
        vm->vsync_len = dmode->vsync_end - dmode->vsync_start;
        vm->vback_porch = dmode->vtotal - dmode->vsync_end;

        vm->pixelclock = dmode->clock * 1000;

        vm->flags = 0;
        if (dmode->flags & DRM_MODE_FLAG_PHSYNC)
                vm->flags |= DISPLAY_FLAGS_HSYNC_HIGH;
        else if (dmode->flags & DRM_MODE_FLAG_NHSYNC)
                vm->flags |= DISPLAY_FLAGS_HSYNC_LOW;
        if (dmode->flags & DRM_MODE_FLAG_PVSYNC)
                vm->flags |= DISPLAY_FLAGS_VSYNC_HIGH;
        else if (dmode->flags & DRM_MODE_FLAG_NVSYNC)
                vm->flags |= DISPLAY_FLAGS_VSYNC_LOW;
        if (dmode->flags & DRM_MODE_FLAG_INTERLACE)
                vm->flags |= DISPLAY_FLAGS_INTERLACED;
        if (dmode->flags & DRM_MODE_FLAG_DBLSCAN)
                vm->flags |= DISPLAY_FLAGS_DOUBLESCAN;
        if (dmode->flags & DRM_MODE_FLAG_DBLCLK)
                vm->flags |= DISPLAY_FLAGS_DOUBLECLK;
}
EXPORT_SYMBOL_GPL(drm_display_mode_to_videomode);

/**
 * drm_bus_flags_from_videomode - extract information about pixelclk and
 * DE polarity from videomode and store it in a separate variable
 * @vm: videomode structure to use
 * @bus_flags: information about pixelclk, sync and DE polarity will be stored
 * here
 *
 * Sets DRM_BUS_FLAG_DE_(LOW|HIGH),  DRM_BUS_FLAG_PIXDATA_DRIVE_(POS|NEG)EDGE
 * and DISPLAY_FLAGS_SYNC_(POS|NEG)EDGE in @bus_flags according to DISPLAY_FLAGS
 * found in @vm
 */
void drm_bus_flags_from_videomode(const struct videomode *vm, u32 *bus_flags)
{
        *bus_flags = 0;
        if (vm->flags & DISPLAY_FLAGS_PIXDATA_POSEDGE)
                *bus_flags |= DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE;
        if (vm->flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
                *bus_flags |= DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE;

        if (vm->flags & DISPLAY_FLAGS_SYNC_POSEDGE)
                *bus_flags |= DRM_BUS_FLAG_SYNC_DRIVE_POSEDGE;
        if (vm->flags & DISPLAY_FLAGS_SYNC_NEGEDGE)
                *bus_flags |= DRM_BUS_FLAG_SYNC_DRIVE_NEGEDGE;

        if (vm->flags & DISPLAY_FLAGS_DE_LOW)
                *bus_flags |= DRM_BUS_FLAG_DE_LOW;
        if (vm->flags & DISPLAY_FLAGS_DE_HIGH)
                *bus_flags |= DRM_BUS_FLAG_DE_HIGH;
}
EXPORT_SYMBOL_GPL(drm_bus_flags_from_videomode);

#ifdef CONFIG_OF
/**
 * of_get_drm_display_mode - get a drm_display_mode from devicetree
 * @np: device_node with the timing specification
 * @dmode: will be set to the return value
 * @bus_flags: information about pixelclk, sync and DE polarity
 * @index: index into the list of display timings in devicetree
 *
 * This function is expensive and should only be used, if only one mode is to be
 * read from DT. To get multiple modes start with of_get_display_timings and
 * work with that instead.
 *
 * Returns:
 * 0 on success, a negative errno code when no of videomode node was found.
 */
int of_get_drm_display_mode(struct device_node *np,
                            struct drm_display_mode *dmode, u32 *bus_flags,
                            int index)
{
        struct videomode vm;
        int ret;

        ret = of_get_videomode(np, &vm, index);
        if (ret)
                return ret;

        drm_display_mode_from_videomode(&vm, dmode);
        if (bus_flags)
                drm_bus_flags_from_videomode(&vm, bus_flags);

        pr_debug("%pOF: got %dx%d display mode: " DRM_MODE_FMT "\n",
                 np, vm.hactive, vm.vactive, DRM_MODE_ARG(dmode));

        return 0;
}
EXPORT_SYMBOL_GPL(of_get_drm_display_mode);

/**
 * of_get_drm_panel_display_mode - get a panel-timing drm_display_mode from devicetree
 * @np: device_node with the panel-timing specification
 * @dmode: will be set to the return value
 * @bus_flags: information about pixelclk, sync and DE polarity
 *
 * The mandatory Device Tree properties width-mm and height-mm
 * are read and set on the display mode.
 *
 * Returns:
 * Zero on success, negative error code on failure.
 */
int of_get_drm_panel_display_mode(struct device_node *np,
                                  struct drm_display_mode *dmode, u32 *bus_flags)
{
        u32 width_mm = 0, height_mm = 0;
        struct display_timing timing;
        struct videomode vm;
        int ret;

        ret = of_get_display_timing(np, "panel-timing", &timing);
        if (ret)
                return ret;

        videomode_from_timing(&timing, &vm);

        memset(dmode, 0, sizeof(*dmode));
        drm_display_mode_from_videomode(&vm, dmode);
        if (bus_flags)
                drm_bus_flags_from_videomode(&vm, bus_flags);

        ret = of_property_read_u32(np, "width-mm", &width_mm);
        if (ret)
                return ret;

        ret = of_property_read_u32(np, "height-mm", &height_mm);
        if (ret)
                return ret;

        dmode->width_mm = width_mm;
        dmode->height_mm = height_mm;

        pr_debug(DRM_MODE_FMT "\n", DRM_MODE_ARG(dmode));

        return 0;
}
EXPORT_SYMBOL_GPL(of_get_drm_panel_display_mode);
#endif /* CONFIG_OF */
#endif /* CONFIG_VIDEOMODE_HELPERS */

/**
 * drm_mode_set_name - set the name on a mode
 * @mode: name will be set in this mode
 *
 * Set the name of @mode to a standard format which is <hdisplay>x<vdisplay>
 * with an optional 'i' suffix for interlaced modes.
 */
void drm_mode_set_name(struct drm_display_mode *mode)
{
        bool interlaced = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);

        snprintf(mode->name, DRM_DISPLAY_MODE_LEN, "%dx%d%s",
                 mode->hdisplay, mode->vdisplay,
                 interlaced ? "i" : "");
}
EXPORT_SYMBOL(drm_mode_set_name);

/**
 * drm_mode_vrefresh - get the vrefresh of a mode
 * @mode: mode
 *
 * Returns:
 * @modes's vrefresh rate in Hz, rounded to the nearest integer.
 */
int drm_mode_vrefresh(const struct drm_display_mode *mode)
{
        unsigned int num = 1, den = 1;

        if (mode->htotal == 0 || mode->vtotal == 0)
                return 0;

        if (mode->flags & DRM_MODE_FLAG_INTERLACE)
                num *= 2;
        if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
                den *= 2;
        if (mode->vscan > 1)
                den *= mode->vscan;

        if (check_mul_overflow(mode->clock, num, &num))
                return 0;

        if (check_mul_overflow(mode->htotal * mode->vtotal, den, &den))
                return 0;

        return DIV_ROUND_CLOSEST_ULL(mul_u32_u32(num, 1000), den);
}
EXPORT_SYMBOL(drm_mode_vrefresh);

/**
 * drm_mode_get_hv_timing - Fetches hdisplay/vdisplay for given mode
 * @mode: mode to query
 * @hdisplay: hdisplay value to fill in
 * @vdisplay: vdisplay value to fill in
 *
 * The vdisplay value will be doubled if the specified mode is a stereo mode of
 * the appropriate layout.
 */
void drm_mode_get_hv_timing(const struct drm_display_mode *mode,
                            int *hdisplay, int *vdisplay)
{
        struct drm_display_mode adjusted;

        drm_mode_init(&adjusted, mode);

        drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE_ONLY);
        *hdisplay = adjusted.crtc_hdisplay;
        *vdisplay = adjusted.crtc_vdisplay;
}
EXPORT_SYMBOL(drm_mode_get_hv_timing);

/**
 * drm_mode_set_crtcinfo - set CRTC modesetting timing parameters
 * @p: mode
 * @adjust_flags: a combination of adjustment flags
 *
 * Setup the CRTC modesetting timing parameters for @p, adjusting if necessary.
 *
 * - The CRTC_INTERLACE_HALVE_V flag can be used to halve vertical timings of
 *   interlaced modes.
 * - The CRTC_STEREO_DOUBLE flag can be used to compute the timings for
 *   buffers containing two eyes (only adjust the timings when needed, eg. for
 *   "frame packing" or "side by side full").
 * - The CRTC_NO_DBLSCAN and CRTC_NO_VSCAN flags request that adjustment *not*
 *   be performed for doublescan and vscan > 1 modes respectively.
 */
void drm_mode_set_crtcinfo(struct drm_display_mode *p, int adjust_flags)
{
        if (!p)
                return;

        p->crtc_clock = p->clock;
        p->crtc_hdisplay = p->hdisplay;
        p->crtc_hsync_start = p->hsync_start;
        p->crtc_hsync_end = p->hsync_end;
        p->crtc_htotal = p->htotal;
        p->crtc_hskew = p->hskew;
        p->crtc_vdisplay = p->vdisplay;
        p->crtc_vsync_start = p->vsync_start;
        p->crtc_vsync_end = p->vsync_end;
        p->crtc_vtotal = p->vtotal;

        if (p->flags & DRM_MODE_FLAG_INTERLACE) {
                if (adjust_flags & CRTC_INTERLACE_HALVE_V) {
                        p->crtc_vdisplay /= 2;
                        p->crtc_vsync_start /= 2;
                        p->crtc_vsync_end /= 2;
                        p->crtc_vtotal /= 2;
                }
        }

        if (!(adjust_flags & CRTC_NO_DBLSCAN)) {
                if (p->flags & DRM_MODE_FLAG_DBLSCAN) {
                        p->crtc_vdisplay *= 2;
                        p->crtc_vsync_start *= 2;
                        p->crtc_vsync_end *= 2;
                        p->crtc_vtotal *= 2;
                }
        }

        if (!(adjust_flags & CRTC_NO_VSCAN)) {
                if (p->vscan > 1) {
                        p->crtc_vdisplay *= p->vscan;
                        p->crtc_vsync_start *= p->vscan;
                        p->crtc_vsync_end *= p->vscan;
                        p->crtc_vtotal *= p->vscan;
                }
        }

        if (adjust_flags & CRTC_STEREO_DOUBLE) {
                unsigned int layout = p->flags & DRM_MODE_FLAG_3D_MASK;

                switch (layout) {
                case DRM_MODE_FLAG_3D_FRAME_PACKING:
                        p->crtc_clock *= 2;
                        p->crtc_vdisplay += p->crtc_vtotal;
                        p->crtc_vsync_start += p->crtc_vtotal;
                        p->crtc_vsync_end += p->crtc_vtotal;
                        p->crtc_vtotal += p->crtc_vtotal;
                        break;
                }
        }

        p->crtc_vblank_start = min(p->crtc_vsync_start, p->crtc_vdisplay);
        p->crtc_vblank_end = max(p->crtc_vsync_end, p->crtc_vtotal);
        p->crtc_hblank_start = min(p->crtc_hsync_start, p->crtc_hdisplay);
        p->crtc_hblank_end = max(p->crtc_hsync_end, p->crtc_htotal);
}
EXPORT_SYMBOL(drm_mode_set_crtcinfo);

/**
 * drm_mode_copy - copy the mode
 * @dst: mode to overwrite
 * @src: mode to copy
 *
 * Copy an existing mode into another mode, preserving the
 * list head of the destination mode.
 */
void drm_mode_copy(struct drm_display_mode *dst, const struct drm_display_mode *src)
{
        struct list_head head = dst->head;

        *dst = *src;
        dst->head = head;
}
EXPORT_SYMBOL(drm_mode_copy);

/**
 * drm_mode_init - initialize the mode from another mode
 * @dst: mode to overwrite
 * @src: mode to copy
 *
 * Copy an existing mode into another mode, zeroing the
 * list head of the destination mode. Typically used
 * to guarantee the list head is not left with stack
 * garbage in on-stack modes.
 */
void drm_mode_init(struct drm_display_mode *dst, const struct drm_display_mode *src)
{
        memset(dst, 0, sizeof(*dst));
        drm_mode_copy(dst, src);
}
EXPORT_SYMBOL(drm_mode_init);

/**
 * drm_mode_duplicate - allocate and duplicate an existing mode
 * @dev: drm_device to allocate the duplicated mode for
 * @mode: mode to duplicate
 *
 * Just allocate a new mode, copy the existing mode into it, and return
 * a pointer to it.  Used to create new instances of established modes.
 *
 * Returns:
 * Pointer to duplicated mode on success, NULL on error.
 */
struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
                                            const struct drm_display_mode *mode)
{
        struct drm_display_mode *nmode;

        nmode = drm_mode_create(dev);
        if (!nmode)
                return NULL;

        drm_mode_copy(nmode, mode);

        return nmode;
}
EXPORT_SYMBOL(drm_mode_duplicate);

static bool drm_mode_match_timings(const struct drm_display_mode *mode1,
                                   const struct drm_display_mode *mode2)
{
        return mode1->hdisplay == mode2->hdisplay &&
                mode1->hsync_start == mode2->hsync_start &&
                mode1->hsync_end == mode2->hsync_end &&
                mode1->htotal == mode2->htotal &&
                mode1->hskew == mode2->hskew &&
                mode1->vdisplay == mode2->vdisplay &&
                mode1->vsync_start == mode2->vsync_start &&
                mode1->vsync_end == mode2->vsync_end &&
                mode1->vtotal == mode2->vtotal &&
                mode1->vscan == mode2->vscan;
}

static bool drm_mode_match_clock(const struct drm_display_mode *mode1,
                                  const struct drm_display_mode *mode2)
{
        /*
         * do clock check convert to PICOS
         * so fb modes get matched the same
         */
        if (mode1->clock && mode2->clock)
                return KHZ2PICOS(mode1->clock) == KHZ2PICOS(mode2->clock);
        else
                return mode1->clock == mode2->clock;
}

static bool drm_mode_match_flags(const struct drm_display_mode *mode1,
                                 const struct drm_display_mode *mode2)
{
        return (mode1->flags & ~DRM_MODE_FLAG_3D_MASK) ==
                (mode2->flags & ~DRM_MODE_FLAG_3D_MASK);
}

static bool drm_mode_match_3d_flags(const struct drm_display_mode *mode1,
                                    const struct drm_display_mode *mode2)
{
        return (mode1->flags & DRM_MODE_FLAG_3D_MASK) ==
                (mode2->flags & DRM_MODE_FLAG_3D_MASK);
}

static bool drm_mode_match_aspect_ratio(const struct drm_display_mode *mode1,
                                        const struct drm_display_mode *mode2)
{
        return mode1->picture_aspect_ratio == mode2->picture_aspect_ratio;
}

/**
 * drm_mode_match - test modes for (partial) equality
 * @mode1: first mode
 * @mode2: second mode
 * @match_flags: which parts need to match (DRM_MODE_MATCH_*)
 *
 * Check to see if @mode1 and @mode2 are equivalent.
 *
 * Returns:
 * True if the modes are (partially) equal, false otherwise.
 */
bool drm_mode_match(const struct drm_display_mode *mode1,
                    const struct drm_display_mode *mode2,
                    unsigned int match_flags)
{
        if (!mode1 && !mode2)
                return true;

        if (!mode1 || !mode2)
                return false;

        if (match_flags & DRM_MODE_MATCH_TIMINGS &&
            !drm_mode_match_timings(mode1, mode2))
                return false;

        if (match_flags & DRM_MODE_MATCH_CLOCK &&
            !drm_mode_match_clock(mode1, mode2))
                return false;

        if (match_flags & DRM_MODE_MATCH_FLAGS &&
            !drm_mode_match_flags(mode1, mode2))
                return false;

        if (match_flags & DRM_MODE_MATCH_3D_FLAGS &&
            !drm_mode_match_3d_flags(mode1, mode2))
                return false;

        if (match_flags & DRM_MODE_MATCH_ASPECT_RATIO &&
            !drm_mode_match_aspect_ratio(mode1, mode2))
                return false;

        return true;
}
EXPORT_SYMBOL(drm_mode_match);

/**
 * drm_mode_equal - test modes for equality
 * @mode1: first mode
 * @mode2: second mode
 *
 * Check to see if @mode1 and @mode2 are equivalent.
 *
 * Returns:
 * True if the modes are equal, false otherwise.
 */
bool drm_mode_equal(const struct drm_display_mode *mode1,
                    const struct drm_display_mode *mode2)
{
        return drm_mode_match(mode1, mode2,
                              DRM_MODE_MATCH_TIMINGS |
                              DRM_MODE_MATCH_CLOCK |
                              DRM_MODE_MATCH_FLAGS |
                              DRM_MODE_MATCH_3D_FLAGS|
                              DRM_MODE_MATCH_ASPECT_RATIO);
}
EXPORT_SYMBOL(drm_mode_equal);

/**
 * drm_mode_equal_no_clocks - test modes for equality
 * @mode1: first mode
 * @mode2: second mode
 *
 * Check to see if @mode1 and @mode2 are equivalent, but
 * don't check the pixel clocks.
 *
 * Returns:
 * True if the modes are equal, false otherwise.
 */
bool drm_mode_equal_no_clocks(const struct drm_display_mode *mode1,
                              const struct drm_display_mode *mode2)
{
        return drm_mode_match(mode1, mode2,
                              DRM_MODE_MATCH_TIMINGS |
                              DRM_MODE_MATCH_FLAGS |
                              DRM_MODE_MATCH_3D_FLAGS);
}
EXPORT_SYMBOL(drm_mode_equal_no_clocks);

/**
 * drm_mode_equal_no_clocks_no_stereo - test modes for equality
 * @mode1: first mode
 * @mode2: second mode
 *
 * Check to see if @mode1 and @mode2 are equivalent, but
 * don't check the pixel clocks nor the stereo layout.
 *
 * Returns:
 * True if the modes are equal, false otherwise.
 */
bool drm_mode_equal_no_clocks_no_stereo(const struct drm_display_mode *mode1,
                                        const struct drm_display_mode *mode2)
{
        return drm_mode_match(mode1, mode2,
                              DRM_MODE_MATCH_TIMINGS |
                              DRM_MODE_MATCH_FLAGS);
}
EXPORT_SYMBOL(drm_mode_equal_no_clocks_no_stereo);

static enum drm_mode_status
drm_mode_validate_basic(const struct drm_display_mode *mode)
{
        if (mode->type & ~DRM_MODE_TYPE_ALL)
                return MODE_BAD;

        if (mode->flags & ~DRM_MODE_FLAG_ALL)
                return MODE_BAD;

        if ((mode->flags & DRM_MODE_FLAG_3D_MASK) > DRM_MODE_FLAG_3D_MAX)
                return MODE_BAD;

        if (mode->clock == 0)
                return MODE_CLOCK_LOW;

        if (mode->hdisplay == 0 ||
            mode->hsync_start < mode->hdisplay ||
            mode->hsync_end < mode->hsync_start ||
            mode->htotal < mode->hsync_end)
                return MODE_H_ILLEGAL;

        if (mode->vdisplay == 0 ||
            mode->vsync_start < mode->vdisplay ||
            mode->vsync_end < mode->vsync_start ||
            mode->vtotal < mode->vsync_end)
                return MODE_V_ILLEGAL;

        return MODE_OK;
}

/**
 * drm_mode_validate_driver - make sure the mode is somewhat sane
 * @dev: drm device
 * @mode: mode to check
 *
 * First do basic validation on the mode, and then allow the driver
 * to check for device/driver specific limitations via the optional
 * &drm_mode_config_helper_funcs.mode_valid hook.
 *
 * Returns:
 * The mode status
 */
enum drm_mode_status
drm_mode_validate_driver(struct drm_device *dev,
                        const struct drm_display_mode *mode)
{
        enum drm_mode_status status;

        status = drm_mode_validate_basic(mode);
        if (status != MODE_OK)
                return status;

        if (dev->mode_config.funcs->mode_valid)
                return dev->mode_config.funcs->mode_valid(dev, mode);
        else
                return MODE_OK;
}
EXPORT_SYMBOL(drm_mode_validate_driver);

/**
 * drm_mode_validate_size - make sure modes adhere to size constraints
 * @mode: mode to check
 * @maxX: maximum width
 * @maxY: maximum height
 *
 * This function is a helper which can be used to validate modes against size
 * limitations of the DRM device/connector. If a mode is too big its status
 * member is updated with the appropriate validation failure code. The list
 * itself is not changed.
 *
 * Returns:
 * The mode status
 */
enum drm_mode_status
drm_mode_validate_size(const struct drm_display_mode *mode,
                       int maxX, int maxY)
{
        if (maxX > 0 && mode->hdisplay > maxX)
                return MODE_VIRTUAL_X;

        if (maxY > 0 && mode->vdisplay > maxY)
                return MODE_VIRTUAL_Y;

        return MODE_OK;
}
EXPORT_SYMBOL(drm_mode_validate_size);

/**
 * drm_mode_validate_ycbcr420 - add 'ycbcr420-only' modes only when allowed
 * @mode: mode to check
 * @connector: drm connector under action
 *
 * This function is a helper which can be used to filter out any YCBCR420
 * only mode, when the source doesn't support it.
 *
 * Returns:
 * The mode status
 */
enum drm_mode_status
drm_mode_validate_ycbcr420(const struct drm_display_mode *mode,
                           struct drm_connector *connector)
{
        if (!connector->ycbcr_420_allowed &&
            drm_mode_is_420_only(&connector->display_info, mode))
                return MODE_NO_420;

        return MODE_OK;
}
EXPORT_SYMBOL(drm_mode_validate_ycbcr420);

#define MODE_STATUS(status) [MODE_ ## status + 3] = #status

static const char * const drm_mode_status_names[] = {
        MODE_STATUS(OK),
        MODE_STATUS(HSYNC),
        MODE_STATUS(VSYNC),
        MODE_STATUS(H_ILLEGAL),
        MODE_STATUS(V_ILLEGAL),
        MODE_STATUS(BAD_WIDTH),
        MODE_STATUS(NOMODE),
        MODE_STATUS(NO_INTERLACE),
        MODE_STATUS(NO_DBLESCAN),
        MODE_STATUS(NO_VSCAN),
        MODE_STATUS(MEM),
        MODE_STATUS(VIRTUAL_X),
        MODE_STATUS(VIRTUAL_Y),
        MODE_STATUS(MEM_VIRT),
        MODE_STATUS(NOCLOCK),
        MODE_STATUS(CLOCK_HIGH),
        MODE_STATUS(CLOCK_LOW),
        MODE_STATUS(CLOCK_RANGE),
        MODE_STATUS(BAD_HVALUE),
        MODE_STATUS(BAD_VVALUE),
        MODE_STATUS(BAD_VSCAN),
        MODE_STATUS(HSYNC_NARROW),
        MODE_STATUS(HSYNC_WIDE),
        MODE_STATUS(HBLANK_NARROW),
        MODE_STATUS(HBLANK_WIDE),
        MODE_STATUS(VSYNC_NARROW),
        MODE_STATUS(VSYNC_WIDE),
        MODE_STATUS(VBLANK_NARROW),
        MODE_STATUS(VBLANK_WIDE),
        MODE_STATUS(PANEL),
        MODE_STATUS(INTERLACE_WIDTH),
        MODE_STATUS(ONE_WIDTH),
        MODE_STATUS(ONE_HEIGHT),
        MODE_STATUS(ONE_SIZE),
        MODE_STATUS(NO_REDUCED),
        MODE_STATUS(NO_STEREO),
        MODE_STATUS(NO_420),
        MODE_STATUS(STALE),
        MODE_STATUS(BAD),
        MODE_STATUS(ERROR),
};

#undef MODE_STATUS

const char *drm_get_mode_status_name(enum drm_mode_status status)
{
        int index = status + 3;

        if (WARN_ON(index < 0 || index >= ARRAY_SIZE(drm_mode_status_names)))
                return "";

        return drm_mode_status_names[index];
}

/**
 * drm_mode_prune_invalid - remove invalid modes from mode list
 * @dev: DRM device
 * @mode_list: list of modes to check
 * @verbose: be verbose about it
 *
 * This helper function can be used to prune a display mode list after
 * validation has been completed. All modes whose status is not MODE_OK will be
 * removed from the list, and if @verbose the status code and mode name is also
 * printed to dmesg.
 */
void drm_mode_prune_invalid(struct drm_device *dev,
                            struct list_head *mode_list, bool verbose)
{
        struct drm_display_mode *mode, *t;

        list_for_each_entry_safe(mode, t, mode_list, head) {
                if (mode->status != MODE_OK) {
                        list_del(&mode->head);
                        if (mode->type & DRM_MODE_TYPE_USERDEF) {
                                drm_warn(dev, "User-defined mode not supported: "
                                         DRM_MODE_FMT "\n", DRM_MODE_ARG(mode));
                        }
                        if (verbose) {
                                drm_dbg_kms(dev, "Rejected mode: " DRM_MODE_FMT " (%s)\n",
                                            DRM_MODE_ARG(mode), drm_get_mode_status_name(mode->status));
                        }
                        drm_mode_destroy(dev, mode);
                }
        }
}
EXPORT_SYMBOL(drm_mode_prune_invalid);

/**
 * drm_mode_compare - compare modes for favorability
 * @priv: unused
 * @lh_a: list_head for first mode
 * @lh_b: list_head for second mode
 *
 * Compare two modes, given by @lh_a and @lh_b, returning a value indicating
 * which is better.
 *
 * Returns:
 * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
 * positive if @lh_b is better than @lh_a.
 */
static int drm_mode_compare(void *priv, const struct list_head *lh_a,
                            const struct list_head *lh_b)
{
        struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
        struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
        int diff;

        diff = ((b->type & DRM_MODE_TYPE_PREFERRED) != 0) -
                ((a->type & DRM_MODE_TYPE_PREFERRED) != 0);
        if (diff)
                return diff;
        diff = b->hdisplay * b->vdisplay - a->hdisplay * a->vdisplay;
        if (diff)
                return diff;

        diff = drm_mode_vrefresh(b) - drm_mode_vrefresh(a);
        if (diff)
                return diff;

        diff = b->clock - a->clock;
        return diff;
}

/**
 * drm_mode_sort - sort mode list
 * @mode_list: list of drm_display_mode structures to sort
 *
 * Sort @mode_list by favorability, moving good modes to the head of the list.
 */
void drm_mode_sort(struct list_head *mode_list)
{
        list_sort(NULL, mode_list, drm_mode_compare);
}
EXPORT_SYMBOL(drm_mode_sort);

/**
 * drm_connector_list_update - update the mode list for the connector
 * @connector: the connector to update
 *
 * This moves the modes from the @connector probed_modes list
 * to the actual mode list. It compares the probed mode against the current
 * list and only adds different/new modes.
 *
 * This is just a helper functions doesn't validate any modes itself and also
 * doesn't prune any invalid modes. Callers need to do that themselves.
 */
void drm_connector_list_update(struct drm_connector *connector)
{
        struct drm_display_mode *pmode, *pt;

        WARN_ON(!mutex_is_locked(&connector->dev->mode_config.mutex));

        list_for_each_entry_safe(pmode, pt, &connector->probed_modes, head) {
                struct drm_display_mode *mode;
                bool found_it = false;

                /* go through current modes checking for the new probed mode */
                list_for_each_entry(mode, &connector->modes, head) {
                        if (!drm_mode_equal(pmode, mode))
                                continue;

                        found_it = true;

                        /*
                         * If the old matching mode is stale (ie. left over
                         * from a previous probe) just replace it outright.
                         * Otherwise just merge the type bits between all
                         * equal probed modes.
                         *
                         * If two probed modes are considered equal, pick the
                         * actual timings from the one that's marked as
                         * preferred (in case the match isn't 100%). If
                         * multiple or zero preferred modes are present, favor
                         * the mode added to the probed_modes list first.
                         */
                        if (mode->status == MODE_STALE) {
                                drm_mode_copy(mode, pmode);
                        } else if ((mode->type & DRM_MODE_TYPE_PREFERRED) == 0 &&
                                   (pmode->type & DRM_MODE_TYPE_PREFERRED) != 0) {
                                pmode->type |= mode->type;
                                drm_mode_copy(mode, pmode);
                        } else {
                                mode->type |= pmode->type;
                        }

                        list_del(&pmode->head);
                        drm_mode_destroy(connector->dev, pmode);
                        break;
                }

                if (!found_it) {
                        list_move_tail(&pmode->head, &connector->modes);
                }
        }
}
EXPORT_SYMBOL(drm_connector_list_update);

static int drm_mode_parse_cmdline_bpp(const char *str, char **end_ptr,
                                      struct drm_cmdline_mode *mode)
{
        unsigned int bpp;

        if (str[0] != '-')
                return -EINVAL;

        str++;
        bpp = simple_strtol(str, end_ptr, 10);
        if (*end_ptr == str)
                return -EINVAL;

        mode->bpp = bpp;
        mode->bpp_specified = true;

        return 0;
}

static int drm_mode_parse_cmdline_refresh(const char *str, char **end_ptr,
                                          struct drm_cmdline_mode *mode)
{
        unsigned int refresh;

        if (str[0] != '@')
                return -EINVAL;

        str++;
        refresh = simple_strtol(str, end_ptr, 10);
        if (*end_ptr == str)
                return -EINVAL;

        mode->refresh = refresh;
        mode->refresh_specified = true;

        return 0;
}

static int drm_mode_parse_cmdline_extra(const char *str, int length,
                                        bool freestanding,
                                        const struct drm_connector *connector,
                                        struct drm_cmdline_mode *mode)
{
        int i;

        for (i = 0; i < length; i++) {
                switch (str[i]) {
                case 'i':
                        if (freestanding)
                                return -EINVAL;

                        mode->interlace = true;
                        break;
                case 'm':
                        if (freestanding)
                                return -EINVAL;

                        mode->margins = true;
                        break;
                case 'D':
                        if (mode->force != DRM_FORCE_UNSPECIFIED)
                                return -EINVAL;

                        if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
                            (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
                                mode->force = DRM_FORCE_ON;
                        else
                                mode->force = DRM_FORCE_ON_DIGITAL;
                        break;
                case 'd':
                        if (mode->force != DRM_FORCE_UNSPECIFIED)
                                return -EINVAL;

                        mode->force = DRM_FORCE_OFF;
                        break;
                case 'e':
                        if (mode->force != DRM_FORCE_UNSPECIFIED)
                                return -EINVAL;

                        mode->force = DRM_FORCE_ON;
                        break;
                default:
                        return -EINVAL;
                }
        }

        return 0;
}

static int drm_mode_parse_cmdline_res_mode(const char *str, unsigned int length,
                                           bool extras,
                                           const struct drm_connector *connector,
                                           struct drm_cmdline_mode *mode)
{
        const char *str_start = str;
        bool rb = false, cvt = false;
        int xres = 0, yres = 0;
        int remaining, i;
        char *end_ptr;

        xres = simple_strtol(str, &end_ptr, 10);
        if (end_ptr == str)
                return -EINVAL;

        if (end_ptr[0] != 'x')
                return -EINVAL;
        end_ptr++;

        str = end_ptr;
        yres = simple_strtol(str, &end_ptr, 10);
        if (end_ptr == str)
                return -EINVAL;

        remaining = length - (end_ptr - str_start);
        if (remaining < 0)
                return -EINVAL;

        for (i = 0; i < remaining; i++) {
                switch (end_ptr[i]) {
                case 'M':
                        cvt = true;
                        break;
                case 'R':
                        rb = true;
                        break;
                default:
                        /*
                         * Try to pass that to our extras parsing
                         * function to handle the case where the
                         * extras are directly after the resolution
                         */
                        if (extras) {
                                int ret = drm_mode_parse_cmdline_extra(end_ptr + i,
                                                                       1,
                                                                       false,
                                                                       connector,
                                                                       mode);
                                if (ret)
                                        return ret;
                        } else {
                                return -EINVAL;
                        }
                }
        }

        mode->xres = xres;
        mode->yres = yres;
        mode->cvt = cvt;
        mode->rb = rb;

        return 0;
}

static int drm_mode_parse_cmdline_int(const char *delim, unsigned int *int_ret)
{
        const char *value;
        char *endp;

        /*
         * delim must point to the '=', otherwise it is a syntax error and
         * if delim points to the terminating zero, then delim + 1 will point
         * past the end of the string.
         */
        if (*delim != '=')
                return -EINVAL;

        value = delim + 1;
        *int_ret = simple_strtol(value, &endp, 10);

        /* Make sure we have parsed something */
        if (endp == value)
                return -EINVAL;

        return 0;
}

static int drm_mode_parse_panel_orientation(const char *delim,
                                            struct drm_cmdline_mode *mode)
{
        const char *value;

        if (*delim != '=')
                return -EINVAL;

        value = delim + 1;
        delim = strchr(value, ',');
        if (!delim)
                delim = value + strlen(value);

        if (!strncmp(value, "normal", delim - value))
                mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
        else if (!strncmp(value, "upside_down", delim - value))
                mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
        else if (!strncmp(value, "left_side_up", delim - value))
                mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
        else if (!strncmp(value, "right_side_up", delim - value))
                mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
        else
                return -EINVAL;

        return 0;
}

static int drm_mode_parse_tv_mode(const char *delim,
                                  struct drm_cmdline_mode *mode)
{
        const char *value;
        int ret;

        if (*delim != '=')
                return -EINVAL;

        value = delim + 1;
        delim = strchr(value, ',');
        if (!delim)
                delim = value + strlen(value);

        ret = drm_get_tv_mode_from_name(value, delim - value);
        if (ret < 0)
                return ret;

        mode->tv_mode_specified = true;
        mode->tv_mode = ret;

        return 0;
}

static int drm_mode_parse_cmdline_options(const char *str,
                                          bool freestanding,
                                          const struct drm_connector *connector,
                                          struct drm_cmdline_mode *mode)
{
        unsigned int deg, margin, rotation = 0;
        const char *delim, *option, *sep;

        option = str;
        do {
                delim = strchr(option, '=');
                if (!delim) {
                        delim = strchr(option, ',');

                        if (!delim)
                                delim = option + strlen(option);
                }

                if (!strncmp(option, "rotate", delim - option)) {
                        if (drm_mode_parse_cmdline_int(delim, &deg))
                                return -EINVAL;

                        switch (deg) {
                        case 0:
                                rotation |= DRM_MODE_ROTATE_0;
                                break;

                        case 90:
                                rotation |= DRM_MODE_ROTATE_90;
                                break;

                        case 180:
                                rotation |= DRM_MODE_ROTATE_180;
                                break;

                        case 270:
                                rotation |= DRM_MODE_ROTATE_270;
                                break;

                        default:
                                return -EINVAL;
                        }
                } else if (!strncmp(option, "reflect_x", delim - option)) {
                        rotation |= DRM_MODE_REFLECT_X;
                } else if (!strncmp(option, "reflect_y", delim - option)) {
                        rotation |= DRM_MODE_REFLECT_Y;
                } else if (!strncmp(option, "margin_right", delim - option)) {
                        if (drm_mode_parse_cmdline_int(delim, &margin))
                                return -EINVAL;

                        mode->tv_margins.right = margin;
                } else if (!strncmp(option, "margin_left", delim - option)) {
                        if (drm_mode_parse_cmdline_int(delim, &margin))
                                return -EINVAL;

                        mode->tv_margins.left = margin;
                } else if (!strncmp(option, "margin_top", delim - option)) {
                        if (drm_mode_parse_cmdline_int(delim, &margin))
                                return -EINVAL;

                        mode->tv_margins.top = margin;
                } else if (!strncmp(option, "margin_bottom", delim - option)) {
                        if (drm_mode_parse_cmdline_int(delim, &margin))
                                return -EINVAL;

                        mode->tv_margins.bottom = margin;
                } else if (!strncmp(option, "panel_orientation", delim - option)) {
                        if (drm_mode_parse_panel_orientation(delim, mode))
                                return -EINVAL;
                } else if (!strncmp(option, "tv_mode", delim - option)) {
                        if (drm_mode_parse_tv_mode(delim, mode))
                                return -EINVAL;
                } else {
                        return -EINVAL;
                }
                sep = strchr(delim, ',');
                option = sep + 1;
        } while (sep);

        if (rotation && freestanding)
                return -EINVAL;

        if (!(rotation & DRM_MODE_ROTATE_MASK))
                rotation |= DRM_MODE_ROTATE_0;

        /* Make sure there is exactly one rotation defined */
        if (!is_power_of_2(rotation & DRM_MODE_ROTATE_MASK))
                return -EINVAL;

        mode->rotation_reflection = rotation;

        return 0;
}

struct drm_named_mode {
        const char *name;
        unsigned int pixel_clock_khz;
        unsigned int xres;
        unsigned int yres;
        unsigned int flags;
        unsigned int tv_mode;
};

#define NAMED_MODE(_name, _pclk, _x, _y, _flags, _mode) \
        {                                               \
                .name = _name,                          \
                .pixel_clock_khz = _pclk,               \
                .xres = _x,                             \
                .yres = _y,                             \
                .flags = _flags,                        \
                .tv_mode = _mode,                       \
        }

static const struct drm_named_mode drm_named_modes[] = {
        NAMED_MODE("NTSC", 13500, 720, 480, DRM_MODE_FLAG_INTERLACE, DRM_MODE_TV_MODE_NTSC),
        NAMED_MODE("NTSC-J", 13500, 720, 480, DRM_MODE_FLAG_INTERLACE, DRM_MODE_TV_MODE_NTSC_J),
        NAMED_MODE("PAL", 13500, 720, 576, DRM_MODE_FLAG_INTERLACE, DRM_MODE_TV_MODE_PAL),
        NAMED_MODE("PAL-M", 13500, 720, 480, DRM_MODE_FLAG_INTERLACE, DRM_MODE_TV_MODE_PAL_M),
};

static int drm_mode_parse_cmdline_named_mode(const char *name,
                                             unsigned int name_end,
                                             struct drm_cmdline_mode *cmdline_mode)
{
        unsigned int i;

        if (!name_end)
                return 0;

        /* If the name starts with a digit, it's not a named mode */
        if (isdigit(name[0]))
                return 0;

        /*
         * If there's an equal sign in the name, the command-line
         * contains only an option and no mode.
         */
        if (strnchr(name, name_end, '='))
                return 0;

        /* The connection status extras can be set without a mode. */
        if (name_end == 1 &&
            (name[0] == 'd' || name[0] == 'D' || name[0] == 'e'))
                return 0;

        /*
         * We're sure we're a named mode at this point, iterate over the
         * list of modes we're aware of.
         */
        for (i = 0; i < ARRAY_SIZE(drm_named_modes); i++) {
                const struct drm_named_mode *mode = &drm_named_modes[i];
                int ret;

                ret = str_has_prefix(name, mode->name);
                if (ret != name_end)
                        continue;

                strscpy(cmdline_mode->name, mode->name, sizeof(cmdline_mode->name));
                cmdline_mode->pixel_clock = mode->pixel_clock_khz;
                cmdline_mode->xres = mode->xres;
                cmdline_mode->yres = mode->yres;
                cmdline_mode->interlace = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
                cmdline_mode->tv_mode = mode->tv_mode;
                cmdline_mode->tv_mode_specified = true;
                cmdline_mode->specified = true;

                return 1;
        }

        return -EINVAL;
}

/**
 * drm_mode_parse_command_line_for_connector - parse command line modeline for connector
 * @mode_option: optional per connector mode option
 * @connector: connector to parse modeline for
 * @mode: preallocated drm_cmdline_mode structure to fill out
 *
 * This parses @mode_option command line modeline for modes and options to
 * configure the connector.
 *
 * This uses the same parameters as the fb modedb.c, except for an extra
 * force-enable, force-enable-digital and force-disable bit at the end::
 *
 *      <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
 *
 * Additionals options can be provided following the mode, using a comma to
 * separate each option. Valid options can be found in
 * Documentation/fb/modedb.rst.
 *
 * The intermediate drm_cmdline_mode structure is required to store additional
 * options from the command line modline like the force-enable/disable flag.
 *
 * Returns:
 * True if a valid modeline has been parsed, false otherwise.
 */
bool drm_mode_parse_command_line_for_connector(const char *mode_option,
                                               const struct drm_connector *connector,
                                               struct drm_cmdline_mode *mode)
{
        const char *name;
        bool freestanding = false, parse_extras = false;
        unsigned int bpp_off = 0, refresh_off = 0, options_off = 0;
        unsigned int mode_end = 0;
        const char *bpp_ptr = NULL, *refresh_ptr = NULL, *extra_ptr = NULL;
        const char *options_ptr = NULL;
        char *bpp_end_ptr = NULL, *refresh_end_ptr = NULL;
        int len, ret;

        memset(mode, 0, sizeof(*mode));
        mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;

        if (!mode_option)
                return false;

        name = mode_option;

        /* Locate the start of named options */
        options_ptr = strchr(name, ',');
        if (options_ptr)
                options_off = options_ptr - name;
        else
                options_off = strlen(name);

        /* Try to locate the bpp and refresh specifiers, if any */
        bpp_ptr = strnchr(name, options_off, '-');
        while (bpp_ptr && !isdigit(bpp_ptr[1]))
                bpp_ptr = strnchr(bpp_ptr + 1, options_off, '-');
        if (bpp_ptr)
                bpp_off = bpp_ptr - name;

        refresh_ptr = strnchr(name, options_off, '@');
        if (refresh_ptr)
                refresh_off = refresh_ptr - name;

        /* Locate the end of the name / resolution, and parse it */
        if (bpp_ptr) {
                mode_end = bpp_off;
        } else if (refresh_ptr) {
                mode_end = refresh_off;
        } else if (options_ptr) {
                mode_end = options_off;
                parse_extras = true;
        } else {
                mode_end = strlen(name);
                parse_extras = true;
        }

        if (!mode_end)
                return false;

        ret = drm_mode_parse_cmdline_named_mode(name, mode_end, mode);
        if (ret < 0)
                return false;

        /*
         * Having a mode that starts by a letter (and thus is named) and
         * an at-sign (used to specify a refresh rate) is disallowed.
         */
        if (ret && refresh_ptr)
                return false;

        /* No named mode? Check for a normal mode argument, e.g. 1024x768 */
        if (!mode->specified && isdigit(name[0])) {
                ret = drm_mode_parse_cmdline_res_mode(name, mode_end,
                                                      parse_extras,
                                                      connector,
                                                      mode);
                if (ret)
                        return false;

                mode->specified = true;
        }

        /* No mode? Check for freestanding extras and/or options */
        if (!mode->specified) {
                unsigned int len = strlen(mode_option);

                if (bpp_ptr || refresh_ptr)
                        return false; /* syntax error */

                if (len == 1 || (len >= 2 && mode_option[1] == ','))
                        extra_ptr = mode_option;
                else
                        options_ptr = mode_option - 1;

                freestanding = true;
        }

        if (bpp_ptr) {
                ret = drm_mode_parse_cmdline_bpp(bpp_ptr, &bpp_end_ptr, mode);
                if (ret)
                        return false;

                mode->bpp_specified = true;
        }

        if (refresh_ptr) {
                ret = drm_mode_parse_cmdline_refresh(refresh_ptr,
                                                     &refresh_end_ptr, mode);
                if (ret)
                        return false;

                mode->refresh_specified = true;
        }

        /*
         * Locate the end of the bpp / refresh, and parse the extras
         * if relevant
         */
        if (bpp_ptr && refresh_ptr)
                extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
        else if (bpp_ptr)
                extra_ptr = bpp_end_ptr;
        else if (refresh_ptr)
                extra_ptr = refresh_end_ptr;

        if (extra_ptr) {
                if (options_ptr)
                        len = options_ptr - extra_ptr;
                else
                        len = strlen(extra_ptr);

                ret = drm_mode_parse_cmdline_extra(extra_ptr, len, freestanding,
                                                   connector, mode);
                if (ret)
                        return false;
        }

        if (options_ptr) {
                ret = drm_mode_parse_cmdline_options(options_ptr + 1,
                                                     freestanding,
                                                     connector, mode);
                if (ret)
                        return false;
        }

        return true;
}
EXPORT_SYMBOL(drm_mode_parse_command_line_for_connector);

static struct drm_display_mode *drm_named_mode(struct drm_device *dev,
                                               struct drm_cmdline_mode *cmd)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(drm_named_modes); i++) {
                const struct drm_named_mode *named_mode = &drm_named_modes[i];

                if (strcmp(cmd->name, named_mode->name))
                        continue;

                if (!cmd->tv_mode_specified)
                        continue;

                return drm_analog_tv_mode(dev,
                                          named_mode->tv_mode,
                                          named_mode->pixel_clock_khz * 1000,
                                          named_mode->xres,
                                          named_mode->yres,
                                          named_mode->flags & DRM_MODE_FLAG_INTERLACE);
        }

        return NULL;
}

/**
 * drm_mode_create_from_cmdline_mode - convert a command line modeline into a DRM display mode
 * @dev: DRM device to create the new mode for
 * @cmd: input command line modeline
 *
 * Returns:
 * Pointer to converted mode on success, NULL on error.
 */
struct drm_display_mode *
drm_mode_create_from_cmdline_mode(struct drm_device *dev,
                                  struct drm_cmdline_mode *cmd)
{
        struct drm_display_mode *mode;

        if (cmd->xres == 0 || cmd->yres == 0)
                return NULL;

        if (strlen(cmd->name))
                mode = drm_named_mode(dev, cmd);
        else if (cmd->cvt)
                mode = drm_cvt_mode(dev,
                                    cmd->xres, cmd->yres,
                                    cmd->refresh_specified ? cmd->refresh : 60,
                                    cmd->rb, cmd->interlace,
                                    cmd->margins);
        else
                mode = drm_gtf_mode(dev,
                                    cmd->xres, cmd->yres,
                                    cmd->refresh_specified ? cmd->refresh : 60,
                                    cmd->interlace,
                                    cmd->margins);
        if (!mode)
                return NULL;

        mode->type |= DRM_MODE_TYPE_USERDEF;
        /* fix up 1368x768: GFT/CVT can't express 1366 width due to alignment */
        if (cmd->xres == 1366)
                drm_mode_fixup_1366x768(mode);
        drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
        return mode;
}
EXPORT_SYMBOL(drm_mode_create_from_cmdline_mode);

/**
 * drm_mode_convert_to_umode - convert a drm_display_mode into a modeinfo
 * @out: drm_mode_modeinfo struct to return to the user
 * @in: drm_display_mode to use
 *
 * Convert a drm_display_mode into a drm_mode_modeinfo structure to return to
 * the user.
 */
void drm_mode_convert_to_umode(struct drm_mode_modeinfo *out,
                               const struct drm_display_mode *in)
{
        out->clock = in->clock;
        out->hdisplay = in->hdisplay;
        out->hsync_start = in->hsync_start;
        out->hsync_end = in->hsync_end;
        out->htotal = in->htotal;
        out->hskew = in->hskew;
        out->vdisplay = in->vdisplay;
        out->vsync_start = in->vsync_start;
        out->vsync_end = in->vsync_end;
        out->vtotal = in->vtotal;
        out->vscan = in->vscan;
        out->vrefresh = drm_mode_vrefresh(in);
        out->flags = in->flags;
        out->type = in->type;

        switch (in->picture_aspect_ratio) {
        case HDMI_PICTURE_ASPECT_4_3:
                out->flags |= DRM_MODE_FLAG_PIC_AR_4_3;
                break;
        case HDMI_PICTURE_ASPECT_16_9:
                out->flags |= DRM_MODE_FLAG_PIC_AR_16_9;
                break;
        case HDMI_PICTURE_ASPECT_64_27:
                out->flags |= DRM_MODE_FLAG_PIC_AR_64_27;
                break;
        case HDMI_PICTURE_ASPECT_256_135:
                out->flags |= DRM_MODE_FLAG_PIC_AR_256_135;
                break;
        default:
                WARN(1, "Invalid aspect ratio (0%x) on mode\n",
                     in->picture_aspect_ratio);
                fallthrough;
        case HDMI_PICTURE_ASPECT_NONE:
                out->flags |= DRM_MODE_FLAG_PIC_AR_NONE;
                break;
        }

        strscpy_pad(out->name, in->name, sizeof(out->name));
}

/**
 * drm_mode_convert_umode - convert a modeinfo into a drm_display_mode
 * @dev: drm device
 * @out: drm_display_mode to return to the user
 * @in: drm_mode_modeinfo to use
 *
 * Convert a drm_mode_modeinfo into a drm_display_mode structure to return to
 * the caller.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_convert_umode(struct drm_device *dev,
                           struct drm_display_mode *out,
                           const struct drm_mode_modeinfo *in)
{
        if (in->clock > INT_MAX || in->vrefresh > INT_MAX)
                return -ERANGE;

        out->clock = in->clock;
        out->hdisplay = in->hdisplay;
        out->hsync_start = in->hsync_start;
        out->hsync_end = in->hsync_end;
        out->htotal = in->htotal;
        out->hskew = in->hskew;
        out->vdisplay = in->vdisplay;
        out->vsync_start = in->vsync_start;
        out->vsync_end = in->vsync_end;
        out->vtotal = in->vtotal;
        out->vscan = in->vscan;
        out->flags = in->flags;
        /*
         * Old xf86-video-vmware (possibly others too) used to
         * leave 'type' uninitialized. Just ignore any bits we
         * don't like. It's a just hint after all, and more
         * useful for the kernel->userspace direction anyway.
         */
        out->type = in->type & DRM_MODE_TYPE_ALL;
        strscpy_pad(out->name, in->name, sizeof(out->name));

        /* Clearing picture aspect ratio bits from out flags,
         * as the aspect-ratio information is not stored in
         * flags for kernel-mode, but in picture_aspect_ratio.
         */
        out->flags &= ~DRM_MODE_FLAG_PIC_AR_MASK;

        switch (in->flags & DRM_MODE_FLAG_PIC_AR_MASK) {
        case DRM_MODE_FLAG_PIC_AR_4_3:
                out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_4_3;
                break;
        case DRM_MODE_FLAG_PIC_AR_16_9:
                out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_16_9;
                break;
        case DRM_MODE_FLAG_PIC_AR_64_27:
                out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_64_27;
                break;
        case DRM_MODE_FLAG_PIC_AR_256_135:
                out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_256_135;
                break;
        case DRM_MODE_FLAG_PIC_AR_NONE:
                out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_NONE;
                break;
        default:
                return -EINVAL;
        }

        out->status = drm_mode_validate_driver(dev, out);
        if (out->status != MODE_OK)
                return -EINVAL;

        drm_mode_set_crtcinfo(out, CRTC_INTERLACE_HALVE_V);

        return 0;
}

/**
 * drm_mode_is_420_only - if a given videomode can be only supported in YCBCR420
 * output format
 *
 * @display: display under action
 * @mode: video mode to be tested.
 *
 * Returns:
 * true if the mode can be supported in YCBCR420 format
 * false if not.
 */
bool drm_mode_is_420_only(const struct drm_display_info *display,
                          const struct drm_display_mode *mode)
{
        u8 vic = drm_match_cea_mode(mode);

        return test_bit(vic, display->hdmi.y420_vdb_modes);
}
EXPORT_SYMBOL(drm_mode_is_420_only);

/**
 * drm_mode_is_420_also - if a given videomode can be supported in YCBCR420
 * output format also (along with RGB/YCBCR444/422)
 *
 * @display: display under action.
 * @mode: video mode to be tested.
 *
 * Returns:
 * true if the mode can be support YCBCR420 format
 * false if not.
 */
bool drm_mode_is_420_also(const struct drm_display_info *display,
                          const struct drm_display_mode *mode)
{
        u8 vic = drm_match_cea_mode(mode);

        return test_bit(vic, display->hdmi.y420_cmdb_modes);
}
EXPORT_SYMBOL(drm_mode_is_420_also);
/**
 * drm_mode_is_420 - if a given videomode can be supported in YCBCR420
 * output format
 *
 * @display: display under action.
 * @mode: video mode to be tested.
 *
 * Returns:
 * true if the mode can be supported in YCBCR420 format
 * false if not.
 */
bool drm_mode_is_420(const struct drm_display_info *display,
                     const struct drm_display_mode *mode)
{
        return drm_mode_is_420_only(display, mode) ||
                drm_mode_is_420_also(display, mode);
}
EXPORT_SYMBOL(drm_mode_is_420);

/**
 * drm_set_preferred_mode - Sets the preferred mode of a connector
 * @connector: connector whose mode list should be processed
 * @hpref: horizontal resolution of preferred mode
 * @vpref: vertical resolution of preferred mode
 *
 * Marks a mode as preferred if it matches the resolution specified by @hpref
 * and @vpref.
 */
void drm_set_preferred_mode(struct drm_connector *connector,
                            int hpref, int vpref)
{
        struct drm_display_mode *mode;

        list_for_each_entry(mode, &connector->probed_modes, head) {
                if (mode->hdisplay == hpref &&
                    mode->vdisplay == vpref)
                        mode->type |= DRM_MODE_TYPE_PREFERRED;
        }
}
EXPORT_SYMBOL(drm_set_preferred_mode);