drm: Simplify and defend later checks when disabling a crtc

By setting the FB of a CRTC to NULL, we are turning off the CRTC (and so
disable the unused encoders and connectors). As such we can simplify the
later tests by making sure the set->mode is NULL. Setting the
num_connectors to zero means that we do not need to loop over the unused
connectors.

All current usage appears correct, this only builds additional defense
into the routine.

References: https://bugzilla.kernel.org/show_bug.cgi?id=27722
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This commit is contained in:
Chris Wilson 2011-01-31 11:16:33 +00:00
parent 9334ef755f
commit ede3ff5204

View file

@ -497,14 +497,17 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
crtc_funcs = set->crtc->helper_private;
if (!set->mode)
set->fb = NULL;
if (set->fb) {
DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",
set->crtc->base.id, set->fb->base.id,
(int)set->num_connectors, set->x, set->y);
} else {
DRM_DEBUG_KMS("[CRTC:%d] [NOFB] #connectors=%d (x y) (%i %i)\n",
set->crtc->base.id, (int)set->num_connectors,
set->x, set->y);
DRM_DEBUG_KMS("[CRTC:%d] [NOFB]\n", set->crtc->base.id);
set->mode = NULL;
set->num_connectors = 0;
}
dev = set->crtc->dev;