modedb.c

Linux环境下视频显示卡设备的驱动程序源代码

	{ NULL, 60, 1600, 1200, 6172, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 24 1600x1200-65 VESA */
	{ NULL, 65, 1600, 1200, 5698, 304,  64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 25 1600x1200-70 VESA */
	{ NULL, 70, 1600, 1200, 5291, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 26 1600x1200-75 VESA */
	{ NULL, 75, 1600, 1200, 4938, 304, 64, 46, 1, 192, 3, 
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 27 1600x1200-85 VESA */
	{ NULL, 85, 1600, 1200, 4357, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 28 1792x1344-60 VESA */
	{ NULL, 60, 1792, 1344, 4882, 328, 128, 46, 1, 200, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 29 1792x1344-75 VESA */
	{ NULL, 75, 1792, 1344, 3831, 352, 96, 69, 1, 216, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 30 1856x1392-60 VESA */
	{ NULL, 60, 1856, 1392, 4580, 352, 96, 43, 1, 224, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 31 1856x1392-75 VESA */
	{ NULL, 75, 1856, 1392, 3472, 352, 128, 104, 1, 224, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 32 1920x1440-60 VESA */
	{ NULL, 60, 1920, 1440, 4273, 344, 128, 56, 1, 200, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 33 1920x1440-75 VESA */
	{ NULL, 75, 1920, 1440, 3367, 352, 144, 56, 1, 224, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
};
EXPORT_SYMBOL(vesa_modes);
#endif /* CONFIG_FB_MODE_HELPERS */

static int my_atoi(const char *name)
{
    int val = 0;

    for (;; name++) {
	switch (*name) {
	    case '0' ... '9':
		val = 10*val+(*name-'0');
		break;
	    default:
		return val;
	}
    }
}

/**
 *	fb_try_mode - test a video mode
 *	@var: frame buffer user defined part of display
 *	@info: frame buffer info structure
 *	@mode: frame buffer video mode structure
 *	@bpp: color depth in bits per pixel
 *
 *	Tries a video mode to test it's validity for device @info.
 *
 *	Returns 1 on success.
 *
 */

static int fb_try_mode(struct fb_var_screeninfo *var, struct fb_info *info,
		       const struct fb_videomode *mode, unsigned int bpp)
{
    int err = 0;

    DPRINTK("Trying mode %s %dx%d-%d@%d\n", mode->name ? mode->name : "noname",
	    mode->xres, mode->yres, bpp, mode->refresh);
    var->xres = mode->xres;
    var->yres = mode->yres;
    var->xres_virtual = mode->xres;
    var->yres_virtual = mode->yres;
    var->xoffset = 0;
    var->yoffset = 0;
    var->bits_per_pixel = bpp;
    var->activate |= FB_ACTIVATE_TEST;
    var->pixclock = mode->pixclock;
    var->left_margin = mode->left_margin;
    var->right_margin = mode->right_margin;
    var->upper_margin = mode->upper_margin;
    var->lower_margin = mode->lower_margin;
    var->hsync_len = mode->hsync_len;
    var->vsync_len = mode->vsync_len;
    var->sync = mode->sync;
    var->vmode = mode->vmode;
    if (info->fbops->fb_check_var)
    	err = info->fbops->fb_check_var(var, info);
    var->activate &= ~FB_ACTIVATE_TEST;
    return err;
}

/**
 *	fb_find_mode - finds a valid video mode
 *	@var: frame buffer user defined part of display
 *	@info: frame buffer info structure
 *	@mode_option: string video mode to find
 *	@db: video mode database
 *	@dbsize: size of @db
 *	@default_mode: default video mode to fall back to
 *	@default_bpp: default color depth in bits per pixel
 *
 *	Finds a suitable video mode, starting with the specified mode
 *	in @mode_option with fallback to @default_mode.  If
 *	@default_mode fails, all modes in the video mode database will
 *	be tried.
 *
 *	Valid mode specifiers for @mode_option:
 *
 *	<xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m] or
 *	<name>[-<bpp>][@<refresh>]
 *
 *	with <xres>, <yres>, <bpp> and <refresh> decimal numbers and
 *	<name> a string.
 *
 *      If 'M' is present after yres (and before refresh/bpp if present),
 *      the function will compute the timings using VESA(tm) Coordinated
 *      Video Timings (CVT).  If 'R' is present after 'M', will compute with
 *      reduced blanking (for flatpanels).  If 'i' is present, compute
 *      interlaced mode.  If 'm' is present, add margins equal to 1.8%
 *      of xres rounded down to 8 pixels, and 1.8% of yres. The char
 *      'i' and 'm' must be after 'M' and 'R'. Example:
 *
 *      1024x768MR-8@60m - Reduced blank with margins at 60Hz.
 *
 *	NOTE: The passed struct @var is _not_ cleared!  This allows you
 *	to supply values for e.g. the grayscale and accel_flags fields.
 *
 *	Returns zero for failure, 1 if using specified @mode_option,
 *	2 if using specified @mode_option with an ignored refresh rate,
 *	3 if default mode is used, 4 if fall back to any valid mode.
 *
 */

int fb_find_mode(struct fb_var_screeninfo *var,
		 struct fb_info *info, const char *mode_option,
		 const struct fb_videomode *db, unsigned int dbsize,
		 const struct fb_videomode *default_mode,
		 unsigned int default_bpp)
{
    int i;

    /* Set up defaults */
    if (!db) {
	db = modedb;
	dbsize = ARRAY_SIZE(modedb);
    }

    if (!default_mode)
	default_mode = &db[0];

    if (!default_bpp)
	default_bpp = 8;

    /* Did the user specify a video mode? */
    if (!mode_option)
	mode_option = fb_mode_option;
    if (mode_option) {
	const char *name = mode_option;
	unsigned int namelen = strlen(name);
	int res_specified = 0, bpp_specified = 0, refresh_specified = 0;
	unsigned int xres = 0, yres = 0, bpp = default_bpp, refresh = 0;
	int yres_specified = 0, cvt = 0, rb = 0, interlace = 0, margins = 0;
	u32 best, diff, tdiff;

	for (i = namelen-1; i >= 0; i--) {
	    switch (name[i]) {
		case '@':
		    namelen = i;
		    if (!refresh_specified && !bpp_specified &&
			!yres_specified) {
			refresh = my_atoi(&name[i+1]);
			refresh_specified = 1;
			if (cvt || rb)
			    cvt = 0;
		    } else
			goto done;
		    break;
		case '-':
		    namelen = i;
		    if (!bpp_specified && !yres_specified) {
			bpp = my_atoi(&name[i+1]);
			bpp_specified = 1;
			if (cvt || rb)
			    cvt = 0;
		    } else
			goto done;
		    break;
		case 'x':
		    if (!yres_specified) {
			yres = my_atoi(&name[i+1]);
			yres_specified = 1;
		    } else
			goto done;
		    break;
		case '0' ... '9':
		    break;
		case 'M':
		    if (!yres_specified)
			cvt = 1;
		    break;
		case 'R':
		    if (!cvt)
			rb = 1;
		    break;
		case 'm':
		    if (!cvt)
			margins = 1;
		    break;
		case 'i':
		    if (!cvt)
			interlace = 1;
		    break;
		default:
		    goto done;
	    }
	}
	if (i < 0 && yres_specified) {
	    xres = my_atoi(name);
	    res_specified = 1;
	}
done:
	if (cvt) {
	    struct fb_videomode cvt_mode;
	    int ret;

	    DPRINTK("CVT mode %dx%d@%dHz%s%s%s\n", xres, yres,
		    (refresh) ? refresh : 60, (rb) ? " reduced blanking" :
		    "", (margins) ? " with margins" : "", (interlace) ?
		    " interlaced" : "");

	    memset(&cvt_mode, 0, sizeof(cvt_mode));
	    cvt_mode.xres = xres;
	    cvt_mode.yres = yres;
	    cvt_mode.refresh = (refresh) ? refresh : 60;

	    if (interlace)
		cvt_mode.vmode |= FB_VMODE_INTERLACED;
	    else
		cvt_mode.vmode &= ~FB_VMODE_INTERLACED;

	    ret = fb_find_mode_cvt(&cvt_mode, margins, rb);

	    if (!ret && !fb_try_mode(var, info, &cvt_mode, bpp)) {
		DPRINTK("modedb CVT: CVT mode ok\n");
		return 1;
	    }

	    DPRINTK("CVT mode invalid, getting mode from database\n");
	}

	DPRINTK("Trying specified video mode%s %ix%i\n",
	    refresh_specified ? "" : " (ignoring refresh rate)", xres, yres);

	if (!refresh_specified) {
		/*
		 * If the caller has provided a custom mode database and a
		 * valid monspecs structure, we look for the mode with the
		 * highest refresh rate.  Otherwise we play it safe it and
		 * try to find a mode with a refresh rate closest to the
		 * standard 60 Hz.
		 */
		if (db != modedb &&
		    info->monspecs.vfmin && info->monspecs.vfmax &&
		    info->monspecs.hfmin && info->monspecs.hfmax &&
		    info->monspecs.dclkmax) {
			refresh = 1000;
		} else {
			refresh = 60;
		}
	}

	diff = -1;
	best = -1;
	for (i = 0; i < dbsize; i++) {
		if ((name_matches(db[i], name, namelen) ||
		    (res_specified && res_matches(db[i], xres, yres))) &&
		    !fb_try_mode(var, info, &db[i], bpp)) {
			if (refresh_specified && db[i].refresh == refresh) {
				return 1;
			} else {
				if (abs(db[i].refresh - refresh) < diff) {
					diff = abs(db[i].refresh - refresh);
					best = i;
				}
			}
		}
	}
	if (best != -1) {
		fb_try_mode(var, info, &db[best], bpp);
		return (refresh_specified) ? 2 : 1;
	}

	diff = 2 * (xres + yres);
	best = -1;
	DPRINTK("Trying best-fit modes\n");
	for (i = 0; i < dbsize; i++) {
		DPRINTK("Trying %ix%i\n", db[i].xres, db[i].yres);
		if (!fb_try_mode(var, info, &db[i], bpp)) {
			tdiff = abs(db[i].xres - xres) +
				abs(db[i].yres - yres);

			/*
			 * Penalize modes with resolutions smaller
			 * than requested.
			 */
			if (xres > db[i].xres || yres > db[i].yres)
				tdiff += xres + yres;

			if (diff > tdiff) {
				diff = tdiff;
				best = i;
			}
		}
	}
	if (best != -1) {
	    fb_try_mode(var, info, &db[best], bpp);
	    return 5;
	}
    }

    DPRINTK("Trying default video mode\n");
    if (!fb_try_mode(var, info, default_mode, default_bpp))
	return 3;

    DPRINTK("Trying all modes\n");
    for (i = 0; i < dbsize; i++)
	if (!fb_try_mode(var, info, &db[i], default_bpp))
	    return 4;

    DPRINTK("No valid mode found\n");
    return 0;
}

/**
 * fb_var_to_videomode - convert fb_var_screeninfo to fb_videomode
 * @mode: pointer to struct fb_videomode
 * @var: pointer to struct fb_var_screeninfo
 */
void fb_var_to_videomode(struct fb_videomode *mode,
			 const struct fb_var_screeninfo *var)
{
	u32 pixclock, hfreq, htotal, vtotal;

	mode->name = NULL;
	mode->xres = var->xres;
	mode->yres = var->yres;
	mode->pixclock = var->pixclock;