[PATCH 2/2] rtc: omap: add rtc wakeup support to alarm events
gururaja.hebbar at ti.com
Fri Jun 14 07:38:41 EDT 2013
On Fri, Jun 14, 2013 at 03:51:43, Kevin Hilman wrote:
> "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.
Ok. I will add the property using a new DT compatibility.
> The driver should always do a device_init_wakeup(dev, true), *except*
> for devtypes that don't have this feature.
"wakeup capable" and "irq-wake-enable-for-alarm-event" are different
For "irq-wake-enable-for-alarm-event", I will add a new DT compability.
However, wakeup capable notification is done in another patch using the a
DT property "ti,wakeup_capable".
The reason for using a dt property is specified below
Author: Sekhar Nori <nsekhar at ti.com>
Date: Wed Oct 27 15:33:05 2010 -0700
rtc: omap: let device wakeup capability be configured from chip
The rtc-omap driver currently hardcodes the RTC wakeup
capability to be "not capable". While this seems to be true for
existing OMAP1 boards which are not wired for this, the
DA850/OMAP-L138 SoC, the RTC can always be wake up source from
its "deep sleep" mode.
So I cannot directly add device_init_wakeup(dev, true), inside driver code.
So, I added a DT property
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