lkml.org 
[lkml]   [2023]   [Dec]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v1 3/6] of: irq: add wake capable bit to of_irq_resource()
On Fri, Dec 15, 2023 at 8:30 AM Rob Herring <robh@kernel.org> wrote:
>
> On Thu, Dec 14, 2023 at 02:05:16PM -0700, Mark Hasemeyer wrote:
> > > If a device has multiple interrupts, but none named "wakeup" you are
> > > saying all the interrupts are wakeup capable. That's not right though.
> > > Only the device knows which interrupts are wakeup capable. You need:
> > >
> > > return wakeindex >= 0 && wakeindex == index;
> >
> > I was assuming logic described in the DT bindings:
> > https://www.kernel.org/doc/Documentation/devicetree/bindings/power/wakeup-source.txt
> > "Also, if device is marked as a wakeup source, then all the primary
> > interrupt(s) can be used as wakeup interrupt(s)."
>
> Also not the best wording I think.
>
> Which interrupts are primary interrupts?
>
> If we can't determine which interrupt, then we should just leave it up
> to the device.
>
> Rob

+Sudeep who authored the documentation and Rob Ack'd: a68eee4c748c
("Documentation: devicetree: standardize/consolidate on "wakeup-source"
property")

I think what Rob is suggesting more closely matches what ACPI supports: where
interrupt resources are individually marked as wake capable. The binding
documentation should be updated though.

Something like:
```
If the device is marked as a wakeup-source, interrupt wake capability depends
on the device specific "interrupt-names" property. If no interrupts are labeled
as wake capable, then it is up to the device to determine which interrupts can
wake the system.

However if a device has a dedicated interrupt as the wakeup source, then it
needs to specify/identify it using a device specific interrupt name. In such
cases only that interrupt can be used as a wakeup interrupt.

While various legacy interrupt names exist, new devices should use "wakeup" as
the canonical interrupt name.
```

Parts of the kernel (I2C, bluetooth, MMC) assume "wakeup" as the
interrupt-name. I added some wording to clarify the assumption.

Thoughts?

\
 
 \ /
  Last update: 2023-12-15 21:58    [W:0.197 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site