Regards Shashank
On 8/4/2016 9:39 PM, Daniel Vetter wrote: > On Thu, Aug 04, 2016 at 03:31:45PM +0100, Emil Velikov wrote: >> On 4 August 2016 at 14:15, Sharma, Shashank <shashank.sharma at intel.com> >> wrote: >>> On 8/4/2016 5:04 PM, Emil Velikov wrote: >>>> On 4 August 2016 at 11:16, Sharma, Shashank <shashank.sharma at intel.com> >>>> wrote: >>>>> Hello Emil, >>>>> >>>>> Thanks for your time. >>>>> >>>>> I have got mixed opinion on this. >>>>> >>>>> IMHO we should expose them to userspace too, as UI agents like Hardware >>>>> composer/X/Wayland must know what does these >>>>> >>>>> flags means, so that they can display them on the end user screen (like >>>>> settings menu) >>>>> >>>>> But few people even think thats its too complex to be exposed to >>>>> userspace >>>>> agents. >>>>> >>>> If we want these/such flags passed between kernel and user space one must: >>>> - Provide a kernel interface how to do that >>>> - Provide a userspace (acked by respective developers/maintainers) >>>> that the approach is sane and proves useful. >>>> >>>> Since the above can take some time, I'd suggest dropping those from >>>> the UAPI header(s)... for now. >>>> >>>> -Emil >>> Please guide me a bit more on this problem, Emil, Daniel. >>> The reason why I want to pass this to userspace is, so that, HWC/X/any other >>> UI manager, can send a modeset >>> which is accurate upto aspect ratio. >>> >> Nobody(?) is arguing that you don't to pass such information to/from >> userspace :-) >> Your series does the internal parsing/management of the attribute and >> has no actual UAPI implementation and/or userspace references (to >> code/discussions). Thus the UAPI changes should _not_ be part of these >> patches. >> >> Daniel's blog [1] has many educational materials why and how things >> are done upstream. I would kindly invite you to give them (another?) >> courtesy read. > It reuses the already existing uapi mode structure. And since it extends > them both on the probe side and on the modeset set this means userspace > can just pass through the right probed mode and it'll all magically work. > At least that's the idea. > > Now if you actually care about the different bits then you can select the > right mode, but that's about it. So if you want to compensate for the > non-square pixels in rendering then you need to look at it, but otherwise > it's just a case of select the mode you want. I don't see what new > userspace we'd need for that really, current one should all work nicely > as-is. At least the entire point of doing this was seamless support with > existing userspace. > -Daniel Thanks Daniel, you explained the zest of this series better than me :) Regards Shashank
