Hi-just wanted to give some general thoughts here. First off I'm 100% behind the epoch idea, that was one of the ideas I had been thinking of proposing here in the first place but probably forgot at some point down the road. A couple of other things: * I think it would also probably be good to have events for when connectors are added or removed from the system (mainly for MST) * Have we considered having any sort of SYNC event, like what evdev uses for signaling the end of a frame of events for input devices? On Fri, 2019-05-10 at 14:12 +0200, Paul Kocialkowski wrote: > Hi, > > On Tue, 2019-05-07 at 21:57 +0530, Ramalingam C wrote: > > DRM API for generating uevent for a status changes of connector's > > property. > > > > This uevent will have following details related to the status change: > > > > HOTPLUG=1, CONNECTOR=<connector_id> and PROPERTY=<property_id> > > > > Need ACK from this uevent from userspace consumer. > > So we just had some discussions over on IRC and at about the hotplug > issue and came up with similar ideas: > https://lists.freedesktop.org/archives/dri-devel/2019-May/217408.html > > The conclusions of these discussions so far would be to have a more or > less fine grain of uevent reporting depending on what happened. The > point is that we need to cover different cases: > - one or more properties changed; > - the connector status changed; > - something else about the connector changed (e.g. EDID/modes) > > For the first case, we can send out: > HOTPLUG=1 > CONNECTOR=<id> > PROPERTY=<id> > > and no reprobe is required. > > For the second one, something like: > HOTPLUG=1 > CONNECTOR=<id> > STATUS=Connected/Disconnected > > and a connector probe is needed for connected, but not for > disconnected; > > For the third one, we can only indicate the connector: > HOTPLUG=1 > CONNECTOR=<id> > > and a reprobe of the connector is always needed > > Then we still have the legacy case: > HOTPLUG=1 > > where userspace is expected to reprobe all the connectors. > > I think this would deserve to be a separate series on its own. So I am > proposing to take this one off your plate and come up with another > seres implementing this proposal. What do you think? > > Cheers, > > Paul > > > v2: > > Minor fixes at KDoc comments [Daniel] > > v3: > > Check the property is really attached with connector [Daniel] > > > > Signed-off-by: Ramalingam C <ramalingam.c@xxxxxxxxx> > > Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> > > --- > > drivers/gpu/drm/drm_sysfs.c | 35 +++++++++++++++++++++++++++++++++++ > > include/drm/drm_sysfs.h | 5 ++++- > > 2 files changed, 39 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c > > index 18b1ac442997..63fa951a20db 100644 > > --- a/drivers/gpu/drm/drm_sysfs.c > > +++ b/drivers/gpu/drm/drm_sysfs.c > > @@ -21,6 +21,7 @@ > > #include <drm/drm_sysfs.h> > > #include <drm/drmP.h> > > #include "drm_internal.h" > > +#include "drm_crtc_internal.h" > > > > #define to_drm_minor(d) dev_get_drvdata(d) > > #define to_drm_connector(d) dev_get_drvdata(d) > > @@ -320,6 +321,9 @@ void drm_sysfs_lease_event(struct drm_device *dev) > > * Send a uevent for the DRM device specified by @dev. Currently we only > > * set HOTPLUG=1 in the uevent environment, but this could be expanded to > > * deal with other types of events. > > + * > > + * Any new uapi should be using the drm_sysfs_connector_status_event() > > + * for uevents on connector status change. > > */ > > void drm_sysfs_hotplug_event(struct drm_device *dev) > > { > > @@ -332,6 +336,37 @@ void drm_sysfs_hotplug_event(struct drm_device *dev) > > } > > EXPORT_SYMBOL(drm_sysfs_hotplug_event); > > > > +/** > > + * drm_sysfs_connector_status_event - generate a DRM uevent for connector > > + * property status change > > + * @connector: connector on which property status changed > > + * @property: connector property whoes status changed. > > + * > > + * Send a uevent for the DRM device specified by @dev. Currently we > > + * set HOTPLUG=1 and connector id along with the attached property id > > + * related to the status change. > > + */ > > +void drm_sysfs_connector_status_event(struct drm_connector *connector, > > + struct drm_property *property) > > +{ > > + struct drm_device *dev = connector->dev; > > + char hotplug_str[] = "HOTPLUG=1", conn_id[30], prop_id[30]; > > + char *envp[4] = { hotplug_str, conn_id, prop_id, NULL }; > > + > > + WARN_ON(!drm_mode_obj_find_prop_id(&connector->base, > > + property->base.id)); > > + > > + snprintf(conn_id, ARRAY_SIZE(conn_id), > > + "CONNECTOR=%u", connector->base.id); > > + snprintf(prop_id, ARRAY_SIZE(prop_id), > > + "PROPERTY=%u", property->base.id); > > + > > + DRM_DEBUG("generating connector status event\n"); > > + > > + kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp); > > +} > > +EXPORT_SYMBOL(drm_sysfs_connector_status_event); > > + > > static void drm_sysfs_release(struct device *dev) > > { > > kfree(dev); > > diff --git a/include/drm/drm_sysfs.h b/include/drm/drm_sysfs.h > > index 4f311e836cdc..d454ef617b2c 100644 > > --- a/include/drm/drm_sysfs.h > > +++ b/include/drm/drm_sysfs.h > > @@ -4,10 +4,13 @@ > > > > struct drm_device; > > struct device; > > +struct drm_connector; > > +struct drm_property; > > > > int drm_class_device_register(struct device *dev); > > void drm_class_device_unregister(struct device *dev); > > > > void drm_sysfs_hotplug_event(struct drm_device *dev); > > - > > +void drm_sysfs_connector_status_event(struct drm_connector *connector, > > + struct drm_property *property); > > #endif -- Cheers, Lyude Paul _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
