On Wed, Feb 07, 2024 at 03:45:15PM +0200, Hogander, Jouni wrote: > On Wed, 2024-02-07 at 15:26 +0200, Hogander, Jouni wrote: > > On Tue, 2024-02-06 at 17:39 +0200, Imre Deak wrote: > > > Prevent accessing the HW from the SDVO/TV get_modes connector hook. > > > Returning 0 from the hook will make the caller - > > > drm_helper_probe_single_connector_modes() - keep the previously > > > detected > > > mode list of the connector. > > > > > I don't see where this is done? Not sure if looking at wrong place, > > but I see it tries using some override edid and in case that fails > > as well uses drm_add_modes_noedid? Some default and EDID override modes are also added to the connector mode list, similarly to when the HW access in intel_sdvo_get_tv_modes() fails (along with any modes specified via the kernel command line, which happens unconditionally, see drm_helper_probe_add_cmdline_mode()). All the modes detected by the encoder detect and the connector get_modes hooks gets added to the drm_connector::probed_modes list. From this __drm_helper_update_and_validate() will copy any new modes to the drm_connector::modes list (which will be returned to user space/kernel client). Thus, returning 0 from the above TV connector get_modes hook will preserve the list of modes on the drm_connector::modes list from an earlier encoder detect/connector get_modes call. > > > > > > > > Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> > > > --- > > > drivers/gpu/drm/i915/display/intel_sdvo.c | 4 ++++ > > > 1 file changed, 4 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_sdvo.c > > > b/drivers/gpu/drm/i915/display/intel_sdvo.c > > > index 2571ef5a1b211..ccea0efbd136f 100644 > > > --- a/drivers/gpu/drm/i915/display/intel_sdvo.c > > > +++ b/drivers/gpu/drm/i915/display/intel_sdvo.c > > > @@ -2287,6 +2287,7 @@ static const struct drm_display_mode > > > sdvo_tv_modes[] = { > > > static int intel_sdvo_get_tv_modes(struct drm_connector > > > *connector) > > > > I see intel_sdvo_get_tv_modes is called from intel_sdvo_get_modes. > > Why > > there is no need to do the same in intel_sdvo_get_lvds_modes and > > intel_sdvo_get_ddc_modes as well? > > It seems you are taking care of intel_svdo_get_ddc_modes in next patch. > Intel_svdo_get_lvds_modes doesn't touch the hw -> nothing to do there. > > > > > BR, > > > > Jouni Högander > > > > > { > > > struct intel_sdvo *intel_sdvo = > > > intel_attached_sdvo(to_intel_connector(connector)); > > > + struct drm_i915_private *i915 = to_i915(intel_sdvo- > > > > base.base.dev); > > > struct intel_sdvo_connector *intel_sdvo_connector = > > > to_intel_sdvo_connector(connector); > > > const struct drm_connector_state *conn_state = connector- > > > > state; > > > @@ -2298,6 +2299,9 @@ static int intel_sdvo_get_tv_modes(struct > > > drm_connector *connector) > > > DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", > > > connector->base.id, connector->name); > > > > > > + if (!intel_display_driver_check_access(i915)) > > > + return 0; > > > + > > > /* > > > * Read the list of supported input resolutions for the > > > selected TV > > > * format. > > >