[PATCH] drm: fourcc byteorder: brings header file comments in line with reality.

Gerd Hoffmann kraxel at redhat.com
Fri Apr 21 16:14:31 UTC 2017


> > My personal opinion is that formats in drm_fourcc.h should be 
> > independent of the CPU byte order and the function 
> > drm_mode_legacy_fb_format() and drivers depending on that incorrect 
> > assumption be fixed instead.
> The problem is this isn't a kernel-internal thing any more.  With the
> addition of the ADDFB2 ioctl the fourcc codes became part of the
> kernel/userspace abi ...

Ok, added some printk's to the ADDFB and ADDFB2 code paths and tested a
bit.  Apparently pretty much all userspace still uses the ADDFB ioctl.
xorg (modesetting driver) does.  gnome-shell in wayland mode does.
Seems the big transition to ADDFB2 didn't happen yet.

I guess that makes changing drm_mode_legacy_fb_format + drivers a
reasonable option ...


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