From f5d2b7c28b67d627646b6a0142bc201a7b1516b0 Mon Sep 17 00:00:00 2001 From: Olaf Hering Date: Sun, 15 Dec 2013 21:40:35 +0100 Subject: [PATCH] fbmem: really support wildcard video=options for all fbdev drivers Documentation/fb/modedb.txt states that video=option should be considered a global option. But video_setup and fb_get_options are not coded that way. Instead its required to boot with video=driver:option to set a given option in drvier. This is cumbersome because it requires to know in advance which driver will be active for a given board/kernel. The following patch implements the documented catchall for the fbdev drivers. It is now possible to boot with video=XxY without the need to know the active driver in advance. The specific case it tries to fix is syslinux in the SUSE installer which offers a menu to set a display resolution. Right now this just appends the vga= option the kernel. But in addition to vga= it should be possible to pass a generic video=XxY for all framebuffer/drm drivers. With this change forcing a certain window size of VM displays is now much easier. Today the video= option is stored in a global fb_mode_option. But unfortunately only drm uses it. Note: this change introduces a small memleak if video=option is actually used because fb_mode_option is const. Most drivers use strsep to get to individual options. This could be fixed in a followup patch which always releases the option string in every caller of fb_get_options. Signed-off-by: Olaf Hering Signed-off-by: Tomi Valkeinen --- drivers/video/fbmem.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index 010d19105ebc..cde461932760 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1930,6 +1930,9 @@ int fb_get_options(const char *name, char **option) options = opt + name_len + 1; } } + /* No match, pass global option */ + if (!options && option && fb_mode_option) + options = kstrdup(fb_mode_option, GFP_KERNEL); if (options && !strncmp(options, "off", 3)) retval = 1;