drm: Catch stop possible NULL pointer reference

This was caught by Weiss. Also added some comments to the
fb_changed and mode_changed variables to explain what they do.

Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Tested-by: Thomas White <taw@bitwiz.org.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Jakob Bornecrantz 2009-08-03 13:43:59 +01:00 committed by Dave Airlie
parent 7781de7456
commit 4cb72b1727

View File

@ -706,8 +706,8 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
struct drm_encoder **save_encoders, *new_encoder;
struct drm_framebuffer *old_fb = NULL;
bool save_enabled;
bool mode_changed = false;
bool fb_changed = false;
bool mode_changed = false; /* if true do a full mode set */
bool fb_changed = false; /* if true and !mode_changed just do a flip */
struct drm_connector *connector;
int count = 0, ro, fail = 0;
struct drm_crtc_helper_funcs *crtc_funcs;
@ -758,6 +758,8 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
if (set->crtc->fb == NULL) {
DRM_DEBUG("crtc has no fb, full mode set\n");
mode_changed = true;
} else if (set->fb == NULL) {
mode_changed = true;
} else if ((set->fb->bits_per_pixel !=
set->crtc->fb->bits_per_pixel) ||
set->fb->depth != set->crtc->fb->depth)