Hello Thomas, On 9/5/22 12:57, Thomas Zimmermann wrote: > Hi Javier > > Am 31.08.22 um 13:12 schrieb Javier Martinez Canillas: >> The simpledrm_primary_plane_helper_atomic_check() function is more complex >> than needed. It first checks drm_atomic_helper_check_plane_state() returns >> value to decide whether to return this or zero. >> >> But it could just return that function return value directly. It also does >> a check if new_plane_state->visible isn't set, but returns zero regardless. >> >> Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx> >> --- >> >> drivers/gpu/drm/tiny/simpledrm.c | 15 ++++----------- >> 1 file changed, 4 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c >> index a81f91814595..0be47f40247a 100644 >> --- a/drivers/gpu/drm/tiny/simpledrm.c >> +++ b/drivers/gpu/drm/tiny/simpledrm.c >> @@ -485,21 +485,14 @@ static int simpledrm_primary_plane_helper_atomic_check(struct drm_plane *plane, >> struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(new_state, plane); >> struct drm_crtc *new_crtc = new_plane_state->crtc; >> struct drm_crtc_state *new_crtc_state = NULL; >> - int ret; >> >> if (new_crtc) >> new_crtc_state = drm_atomic_get_new_crtc_state(new_state, new_crtc); >> >> - ret = drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state, >> - DRM_PLANE_NO_SCALING, >> - DRM_PLANE_NO_SCALING, >> - false, false); >> - if (ret) >> - return ret; >> - else if (!new_plane_state->visible) >> - return 0; >> - >> - return 0; >> + return drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state, >> + DRM_PLANE_NO_SCALING, >> + DRM_PLANE_NO_SCALING, >> + false, false); > > I'm undecided on this change. I know it's correct and more to the point. > But the call's logic is non-intuitive: the call either returns an error > or we have to test ->visible afterwards. So I wrote it explicitly. > Yes, but the check has no effect so I found it even less intuitive. Maybe add a comment then if you wan to keep the current code? > I saw that your change to ssd130x also uses the pattern. If we find more > such drivers, we could implement the atomic check as a helper. I suggest > drm_plane_helper_atomic_check_fixed() in drm_plane_helper.c > Sure. I can add a preparatory change in v2 that adds that helper and then use it in the follow-up patch. -- Best regards, Javier Martinez Canillas Core Platforms Red Hat
