• Chris Wilson's avatar
    drm: Differentiate the lack of an interface from invalid parameter · 69fdf420
    Chris Wilson authored
    If the ioctl is not supported on a particular piece of HW/driver
    combination, report ENOTSUP (aka EOPNOTSUPP) so that it can be easily
    distinguished from both the lack of the ioctl and from a regular invalid
    parameter.
    
    v2: Across all the kms ioctls we had a mixture of reporting EINVAL,
    ENODEV and a few ENOTSUPP (most where EINVAL) for a failed
    drm_core_check_feature(). Update everybody to report ENOTSUPP.
    
    v3: ENOTSUPP is an internal errno! It's value (524) does not correspond
    to a POSIX errno, the one we want is ENOTSUP. However,
    uapi/asm-generic/errno.h doesn't include ENOTSUP but man errno says
    
    	"ENOTSUP and EOPNOTSUPP have the same value on Linux,
    	but according to POSIX.1 these error values should be
    	distinct."
    
    so use EOPNOTSUPP as its equivalent.
    Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
    Cc: Daniel Vetter <daniel@ffwll.ch>
    Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
    Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #v2
    Link: https://patchwork.freedesktop.org/patch/msgid/20180913192050.24812-1-chris@chris-wilson.co.uk
    69fdf420
drm_lock.c 9.71 KB