Groetje, Geert,
Geert Uytterhoeven wrote:
par->isVGA = screen_info.orig_video_isVGA;
par->isVGA = screen_info.orig_video_isVGA == VIDEO_TYPE_VGAC;
All non-x86 architectures (except for 2 MIPS platforms) treat orig_video_isVGA as a boolean flag, and just assign 1 to it. Hence this change would break them.
I see a bit of a conflict with using orig_video_isVGA as a boolean. All the modern architecture-agnostic driver code, such as sysfb, sysfb_simplefb, and efifb, all use and expect orig_video_isVGA to be an integer. On the other hand, the VGA driver for XEN first sets orig_video_isVGA = 1 (boolean), and then VIDEO_TYPE_VLFB or VIDEO_TYPE_EFI (integer). Overloading the definition for orig_video_isVGA to be both boolean and integer - within the same file - seems like a recipe for bugs to me.
That said, I think that wrapping the par->isVGA code, above, within a check for CONFIG_X86 seems safe and expedient. But I would be much happier if the non-x86 architectures would set it to a proper integer value (even if fake) that coincidentally satisfies boolean "true", say VIDEO_TYPE_VGAC; that way, there would be no confusion as to data type in all the more recent architecture-agnostic framebuffer code.
Kris