Messages in this thread | | | Date | Fri, 2 Aug 2013 16:37:36 +0530 | From | Gururaja Hebbar <> | Subject | Re: [Patch V2 4/4] ARM: dts: AM33XX: update rtc node compatibility |
| |
On 8/1/2013 10:35 PM, Mark Rutland wrote: > On Tue, Jul 30, 2013 at 05:21:14PM +0100, Sekhar Nori wrote: >> On 7/30/2013 8:25 PM, Mark Rutland wrote: >>> On Tue, Jul 30, 2013 at 06:05:52AM +0100, Gururaja Hebbar wrote: >>>> Hi, >>>> >>>> On 7/3/2013 2:17 PM, Hebbar Gururaja wrote: >>>>> Since AM33xx RTC IP has RTC_IRQWAKEEN to support Alarm Wake-up. >>>>> >>>>> Update the rtc compatible property to "ti,am3352-rtc" to enable handling >>>>> of this feature inside rtc-omap driver. >>>> >>>> The other 2 rtc driver related patches have been pulled up. If you have >>>> no comments, can you please pull this up. >>>> >>>> Regards >>>> Gururaja >>>> >>>>> >>>>> Signed-off-by: Hebbar Gururaja <gururaja.hebbar@ti.com> >>>>> --- >>>>> :100644 100644 77aa1b0... dde180a... M arch/arm/boot/dts/am33xx.dtsi >>>>> arch/arm/boot/dts/am33xx.dtsi | 2 +- >>>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>>> >>>>> diff --git a/arch/arm/boot/dts/am33xx.dtsi b/arch/arm/boot/dts/am33xx.dtsi >>>>> index 77aa1b0..dde180a 100644 >>>>> --- a/arch/arm/boot/dts/am33xx.dtsi >>>>> +++ b/arch/arm/boot/dts/am33xx.dtsi >>>>> @@ -297,7 +297,7 @@ >>>>> }; >>>>> >>>>> rtc@44e3e000 { >>>>> - compatible = "ti,da830-rtc"; >>>>> + compatible = "ti,am3352-rtc"; >>> >>> Given that this is backwards compatible with the old binding, it would >>> be nicer to have this as: >>> >>> compatible = "ti,am3352-rtc", "ti,da830-rtc"; >>> >>> We must get into the habit of changing dts files in a >>> backwards-compatible fashion. >> >> Right, I suggested this when v1 was posted. It turns out the current >> kernel does not handle the compatilble list correctly and the string >> selected actually depends on the order in which it appears in match >> table in driver instead. >> >> I saw there were patches being discussed to fix this issue, but until >> that is fixed, we cannot really use what you (and I before) suggested. > > A temporary solution would be to list the "ti,am3352-rtc" first in the > of_match_table kernel-side.
If above method is followed, then it would cause trouble on davinci platform because this rtc-omap driver is also used by Davinci platform. On davinci Plaform the driver would match with "ti,am3352-rtc" for compatible.
Regards Gururaja
> That way you can keep the old compatible > string in the dts compatible list, and maintain backwards compatibilty > with older kernels. > > Later if the way Linux matches compatible strings is changed, this > shouldn't break the probe order, and the of_match_table order could be > changed. > > Have I missed something? > > Thanks, > Mark. >
| |