[PATCH 2/2] rtc: omap: add rtc wakeup support to alarm events
Kevin Hilman
khilman at linaro.org
Thu Jun 13 18:21:43 EDT 2013
"Hebbar, Gururaja" <gururaja.hebbar at ti.com> writes:
> Hi Kevin,
>
> On Mon, Jun 10, 2013 at 16:55:17, Hebbar, Gururaja wrote:
>> On Fri, May 31, 2013 at 23:11:22, Kevin Hilman wrote:
>> > Hebbar Gururaja <gururaja.hebbar at ti.com> writes:
>> >
>> > > On some platforms (like AM33xx), a special register (RTC_IRQWAKEEN)
>> > > is available to enable Wakeup feature for Alarm Events.
>> > >
>> > > Since new platforms/Boards are now added through DT only, this feature
>> > > is supported via DT property only.
>> >
>> > > Platforms using such IP should add the property "ti,has_irq_wake_enb"
>> > > in rtc DT node.
>> >
>> > This is a property of the IP, not the board. Can't you detect this
>> > based on the revision of the IP?
>>
>> Here is what I found out till now.
>>
>> 1. rtc-omap driver is used by Davinci, OMAP-1/2 & AM33xx SoC.
>>
>> 2. Only AM33xx soc rtc ip has revision register (& populated). Older OMAP
>> Or davinci doesn't have this register.
>>
>> 3. AFAIK, this was the reason why Afzal used platform_device_id &
>> of_device_id->data method to detect new versions (commit
>> 9e0344dcc225fe1a0e8b8af9ff7df44ec4613580)
>>
>>
>> So now either
>> a. I can follow the same method and add new member to omap_rtc_devtype & add a new compatible in
>> omap_rtc_of_match in rtc-omap.c
>>
>> or
>>
>> b. use dt property to indicate existence of above property.
>>
>>
>> Kindly let me know your opinion about the same.
>
> Any update on this. I have patch ready for both the choices. Waiting for your ok to send
I think (a) is better.
The driver should always do a device_init_wakeup(dev, true), *except*
for devtypes that don't have this feature.
Kevin
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