[PATCH 2/2] rtc: omap: add rtc wakeup support to alarm events

Hebbar, Gururaja gururaja.hebbar at ti.com
Mon Jun 10 07:25:17 EDT 2013


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.

> 
> Kevin
> 


Regards, 
Gururaja



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