ping? On Mon, Aug 10, 2015 at 2:04 PM, Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx> wrote: > Hello Hans, Sakari and Laurent: > > I am back from holidays :). Shall I prepare a new patchset with the > suggestion from Hans? > > Thanks! > > On Mon, Jul 20, 2015 at 4:31 PM, Hans Verkuil <hverkuil@xxxxxxxxx> wrote: >> On 07/20/2015 03:52 PM, Ricardo Ribalda Delgado wrote: >>> Hello >>> >>> I have no preference over the two implementations, but I see an issue >>> with this suggestion. >>> >>> >>> What happens to out out tree drivers, or drivers that don't support >>> this functionality? >>> >>> With the ioctl, the user receives a -ENOTTY. So he knows there is >>> something wrong with the driver. >>> >>> With this class, the driver might interpret this a simple G_VAL and >>> return he current value with no way for the user to know what is going >>> on. >> >> Drivers that implement the current API correctly will return an error >> if V4L2_CTRL_WHICH_DEF_VAL was specified. Such drivers will interpret >> the value as a control class, and no control classes in that range exist. >> See also class_check() in v4l2-ctrls.c. >> >> The exception here is uvc which doesn't have this class check and it will >> just return the current value :-( >> >> I don't see a way around this, unfortunately. >> >> Out-of-tree drivers that use the control framework are fine, and I don't >> really care about drivers (out-of-tree or otherwise) that do not use the >> control framework. >> >>> Regarding the new implementation.... I can make some code next week, >>> this week I am 120% busy :) >> >> Wait until there is a decision first :-) >> >> It's not a lot of work, I think. >> >> Regards, >> >> Hans >> >>> What do you think? >>> -- >>> 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 >>> >> > > > > -- > Ricardo Ribalda -- Ricardo Ribalda -- 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
