On Wednesday, June 29, 2011 12:30:26 Laurent Pinchart wrote: > Hi Hans, > > On Wednesday 29 June 2011 12:06:57 Hans Verkuil wrote: > > > On Tuesday 28 June 2011 17:18:07 Hans Verkuil wrote: > > >> Originally no control events would go to the filehandle that called the > > >> VIDIOC_S_CTRL/VIDIOC_S_EXT_CTRLS ioctls. This was to prevent a feedback > > >> loop. > > >> > > >> This is now only done if the new V4L2_EVENT_SUB_FL_NO_FEEDBACK flag is > > >> set. > > > > > > What about doing it the other way around ? Most applications won't want > > > that feedback, you could disable it by default. > > > > I thought about that, but that's harder to explain since that flag would > > then suppress an exception to the normal handling of event. > > > > It's easier to say: events are sent to everyone, but if you set this flag, > > then we make this exception. > > Events are sent to everyone but you, but if you set this flag, you get them as > well. I thought about it a bit more, and a better reason for changing this to ALLOW_FEEDBACK is that it forces you to think about the consequences of setting this flag. I'll change it. Regards, Hans > It's not that hard ;-) > > > I suspect that most applications do not need to set this flag anyway, only > > applications like qv4l2 that create a control panel need it. > > Most applications won't need events for controls they modify themselves. While > this might not break them, it would still be a waste of resources. > > -- > Regards, > > Laurent Pinchart > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
