Hi Sam, On Sun, Jun 21, 2020 at 10:40:00AM +0200, Sam Ravnborg wrote: > On Tue, May 26, 2020 at 04:15:05AM +0300, Laurent Pinchart wrote: > > The DRM CRTC helpers add default modes to connectors in the connected > > state if no mode can be retrieved from the connector. This behaviour is > > useful for VGA or DVI outputs that have no connected DDC bus. However, > > in such cases, the status of the output usually can't be retrieved and > > is reported as connector_status_unknown. > > > > Extend the addition of default modes to connectors in an unknown state > > to support outputs that can retrieve neither the modes nor the > > connection status. > > > > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx> > > From your description sounds like an OK approach. > But this is not something I feel too familiar with. > Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx> Thanks for the ack. I'd like to have Daniel's (CC'ed) feedback on this too. > > --- > > drivers/gpu/drm/drm_probe_helper.c | 3 ++- > > include/drm/drm_modeset_helper_vtables.h | 8 +++++++- > > 2 files changed, 9 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c > > index f5d141e0400f..9055d9573c90 100644 > > --- a/drivers/gpu/drm/drm_probe_helper.c > > +++ b/drivers/gpu/drm/drm_probe_helper.c > > @@ -491,7 +491,8 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, > > if (count == 0 && connector->status == connector_status_connected) > > count = drm_add_override_edid_modes(connector); > > > > - if (count == 0 && connector->status == connector_status_connected) > > + if (count == 0 && (connector->status == connector_status_connected || > > + connector->status == connector_status_unknown)) > > count = drm_add_modes_noedid(connector, 1024, 768); > > count += drm_helper_probe_add_cmdline_mode(connector); > > if (count == 0) > > diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h > > index 421a30f08463..afe55e2e93d2 100644 > > --- a/include/drm/drm_modeset_helper_vtables.h > > +++ b/include/drm/drm_modeset_helper_vtables.h > > @@ -876,13 +876,19 @@ struct drm_connector_helper_funcs { > > * The usual way to implement this is to cache the EDID retrieved in the > > * probe callback somewhere in the driver-private connector structure. > > * In this function drivers then parse the modes in the EDID and add > > - * them by calling drm_add_edid_modes(). But connectors that driver a > > + * them by calling drm_add_edid_modes(). But connectors that drive a > > * fixed panel can also manually add specific modes using > > * drm_mode_probed_add(). Drivers which manually add modes should also > > * make sure that the &drm_connector.display_info, > > * &drm_connector.width_mm and &drm_connector.height_mm fields are > > * filled in. > > * > > + * Note that the caller function will automatically add standard VESA > > + * DMT modes up to 1024x768 if the .get_modes() helper operation returns > > + * no mode and if the connector status is connector_status_connected or > > + * connector_status_unknown. There is no need to call > > + * drm_add_edid_modes() manually in that case. > > + * > > * Virtual drivers that just want some standard VESA mode with a given > > * resolution can call drm_add_modes_noedid(), and mark the preferred > > * one using drm_set_preferred_mode(). -- Regards, Laurent Pinchart _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel