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RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Flag: NO X-Spam-Score: -4.51 Hi Am 08.09.26 um 16:35 schrieb Maxime Ripard: [...] > diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c > index 0dbf04d4aa9e..f13bb7c490c4 100644 > --- a/drivers/gpu/drm/drm_ioctl.c > +++ b/drivers/gpu/drm/drm_ioctl.c > @@ -303,10 +303,13 @@ static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_ > break; > case DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP: > req->value = drm_core_check_feature(dev, DRIVER_ATOMIC) && > dev->mode_config.async_page_flip; > break; > + case DRM_CAP_ATOMIC_RESET: > + req->value = drm_atomic_can_create_state(dev); > + break; Looking at this and the other places where _can_create_state is being used, I'd like to present a different design. Scratch the helper entirely and introduce a dedicated callback in drm_mode_config_funcs that sets up the default state.  Your current helper drm_atomic_commit_fill_with_defaults would be the common implementation. The DRM core could test for the existence of this callback to see if default-reset is available. Sure, we'd have to modify all drivers, but it would be architecturally cleaner IMHO and give full control to the drivers. Best regards Thomas > default: > return -EINVAL; > } > return 0; > } > diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h > index bc7ef7684099..b6e2f2edd122 100644 > --- a/include/uapi/drm/drm.h > +++ b/include/uapi/drm/drm.h > @@ -793,10 +793,20 @@ struct drm_gem_change_handle { > * If set to 1, the driver supports &DRM_MODE_PAGE_FLIP_ASYNC for atomic > * commits. > */ > #define DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP 0x15 > > +/** > + * DRM_CAP_ATOMIC_RESET > + * > + * If set to 1, the driver supports the &DRM_MODE_ATOMIC_RESET flag in > + * &DRM_IOCTL_MODE_ATOMIC commits. When supported, userspace can pass that > + * flag to reset all KMS object states to their defaults before applying > + * property changes. > + */ > +#define DRM_CAP_ATOMIC_RESET 0x16 > + > /* DRM_IOCTL_GET_CAP ioctl argument type */ > struct drm_get_cap { > __u64 capability; > __u64 value; > }; > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h > index ed1a660a3dfd..32eb3f650d7a 100644 > --- a/include/uapi/drm/drm_mode.h > +++ b/include/uapi/drm/drm_mode.h > @@ -1326,10 +1326,21 @@ struct drm_mode_destroy_dumb { > * To the best of the driver's knowledge, visual artifacts are guaranteed to > * not appear when this flag is not set. Some sinks might display visual > * artifacts outside of the driver's control. > */ > #define DRM_MODE_ATOMIC_ALLOW_MODESET 0x0400 > +/** > + * DRM_MODE_ATOMIC_RESET > + * > + * Reset all KMS object states (CRTCs, planes, connectors, color operations) > + * to their default values before applying the properties in this commit. > + * Properties not explicitly included in the commit will remain at their > + * defaults (CRTCs inactive, planes disabled, connectors unbound, etc.). > + * > + * This flag cannot be combined with &DRM_MODE_PAGE_FLIP_ASYNC. > + */ > +#define DRM_MODE_ATOMIC_RESET 0x0800 > > /** > * DRM_MODE_ATOMIC_FLAGS > * > * Bitfield of flags accepted by the &DRM_IOCTL_MODE_ATOMIC IOCTL in > @@ -1338,11 +1349,12 @@ struct drm_mode_destroy_dumb { > #define DRM_MODE_ATOMIC_FLAGS (\ > DRM_MODE_PAGE_FLIP_EVENT |\ > DRM_MODE_PAGE_FLIP_ASYNC |\ > DRM_MODE_ATOMIC_TEST_ONLY |\ > DRM_MODE_ATOMIC_NONBLOCK |\ > - DRM_MODE_ATOMIC_ALLOW_MODESET) > + DRM_MODE_ATOMIC_ALLOW_MODESET |\ > + DRM_MODE_ATOMIC_RESET) > > struct drm_mode_atomic { > __u32 flags; > __u32 count_objs; > __u64 objs_ptr; > -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, (HRB 36809, AG Nürnberg)