fb_find_mode(9)

🌈 fb_find_mode(9) 🌈

okay so bestie, this is the Kernel API Manual entry for fb_find_mode, and it's literally the “find me a valid video mode” bestie of your dreams. no cap. 🫶

💖 NAME 💖

fb_find_mode — finds a valid video mode. periodt. ✨

🦋 SYNOPSIS 🦋

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 );

💅 ARGUMENTS 💅

okay, the cast of characters:

• var — frame buffer user defined part of display. main character energy tbh.
• info — frame buffer info structure.
• mode_option — string video mode to find.
• db — video mode database.
• dbsize — size of db. literally the size, bestie.
• default_mode — default video mode to fall back to.
• default_bpp — default color depth in bits per pixel.

🎀 DESCRIPTION 🎀

It 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. she's persistent. 💅

Valid mode specifiers for mode_option are:

<xres>x<yres>[M][R][-<bpp>][<refresh>][i][p][m]

or :

<name>[-<bpp>][<refresh>]

with <xres>, <yres>, <bpp> and <refresh> decimal numbers and <name> a string. yes bestie, decimal numbers, not vibes. 🎀

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 or p are present, compute interlaced or progressive 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

Then the page just leaves us with “The char” — iconic little fragment — and hits you with this example:

1024x768MR-860m - 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. okay so do not expect a clean slate, bestie — that is the whole point. 🫶

Returns:

• 0 → failure
• 1 → using specified mode_option
• 2 → using specified mode_option with an ignored refresh rate
• 3 → default mode is used
• 4 → fall back to any valid mode

👑 SEE ALSO 👑

Kernel file ./drivers/video/fbdev/core/modedb.c

• fb_try_mode(9)
• fb_var_to_videomode(9)
• fb_videomode_to_var(9)
• fb_mode_is_equal(9)
• fb_find_best_mode(9)
• fb_find_nearest_mode(9)
• fb_match_mode(9)
• fb_add_videomode(9)
• fb_delete_videomode(9)
• fb_destroy_modelist(9)
• fb_videomode_to_modelist(9)

mwah 💋 — page sourced from ./drivers/video/fbdev/core, dated October 2026. that's the footer, bestie, and we're done. 🌸