On Wednesday 04 March 2015 14:53:40 Arun Ramamurthy wrote: > On 15-03-04 02:50 PM, Arnd Bergmann wrote: > > On Wednesday 04 March 2015 14:40:13 Arun Ramamurthy wrote: > >> On 15-03-04 02:21 PM, Arnd Bergmann wrote: > >>> On Thursday 12 February 2015 14:17:41 Arun Ramamurthy wrote: > >>>> Hi Arnd > >>>> > >>>> My apologies for the late reply, I was moved to other work items. I > >>>> wanted to get more clarification on the syscon issue so that I can > >>>> submit the next patch set. If I understand correctly, you would like > >>>> me to move the CRMU logic to a new driver under mfd/ and use the syscon > >>>> api calls in my rtc driver? Thanks > >>> > >>> It depends a lot on what's in there, I can best advise you if you > >>> have some form of register list. > >>> > >>> A common approach would be to not have a driver for the crmu at all, > >>> but just mark it as syscon, and have the other drivers either reference > >>> the syscon node through a phandle, or create them as childrem of > >>> the syscon node. The latter case makes most sense if all uses of > >>> the crmu have no other MMIO registers. > >>> > >> > >> Thank you Arnd, I am going to follow the approach of adding a child node > >> to the syscon node. Several other driver use other registers in the CRMU > >> so I think the child node approach makes the most sense. > > > > Just to be sure we have the same understanding: of those other drivers, > > do you think that they would use only CRMU registers, or could there > > be drivers that have both CRMU as well as other MMIO registers? > > > The other drivers have both CRMU and other MMIO registers. So I thought > they could also switch to using the syscon child nodes. > No, in this case, better not use child nodes at all. When other platforms use child nodes of a syscon, the common case is that they use the 'reg' property to refer to syscon registers, which are in a different address space from other MMIO, and you can't easily mix the two. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
