Re: [PATCH 5/7] soc: brcmstb: add wake-timer driver

From: Brian Norris
Date: Fri Jun 19 2015 - 13:36:31 EST


On Thu, Jun 18, 2015 at 07:20:26PM -0700, Gregory Fong wrote:
> On Thu, Jun 18, 2015 at 5:11 PM, Brian Norris
> <computersforpeace@xxxxxxxxx> wrote:
> > Useful for waking the system from suspend after a specified period of
> > time.
> >
> > This IP could potentially be supported as an RTC driver (for use with
> > the 'rtcwake' utility), but it is not battery backed, so that's not a
> > great fit. Implement a custom sysfs interface instead.
> >
> > Signed-off-by: Brian Norris <computersforpeace@xxxxxxxxx>
> > ---
> > .../ABI/testing/sysfs-driver-wktmr-brcmstb | 12 +
> > drivers/soc/brcmstb/Kconfig | 3 +
> > drivers/soc/brcmstb/Makefile | 1 +
> > drivers/soc/brcmstb/wktmr.c | 242 +++++++++++++++++++++
> > 4 files changed, 258 insertions(+)
> > create mode 100644 Documentation/ABI/testing/sysfs-driver-wktmr-brcmstb
> > create mode 100644 drivers/soc/brcmstb/wktmr.c
> >
> > diff --git a/Documentation/ABI/testing/sysfs-driver-wktmr-brcmstb b/Documentation/ABI/testing/sysfs-driver-wktmr-brcmstb
> > new file mode 100644
> > index 000000000000..e563f8b8d969
> > --- /dev/null
> > +++ b/Documentation/ABI/testing/sysfs-driver-wktmr-brcmstb
> > @@ -0,0 +1,12 @@
> > +What: /sys/bus/platform/drivers/brcm-waketimer/<MMIO-address>.waketimer/timeout
> > +Date: November 21, 2014
> > +KernelVersion: 3.14
> > +Contact: Brian Norris <norris@xxxxxxxxxxxx>
>
> Shouldn't this be "Brian Norris <computersforpeace@xxxxxxxxx>"?

Indeed, thanks. Wouldn't want things bouncing...

> > +Description: The control file for the wakeup timer. This integer value
> > + represents the number of seconds between a suspend operation
> > + (e.g., S3 suspend-to-RAM) and the time at which the wakeup
> > + timer should fire.
> > [...]
> > diff --git a/drivers/soc/brcmstb/wktmr.c b/drivers/soc/brcmstb/wktmr.c
> > new file mode 100644
> > index 000000000000..89f989724d3c
> > --- /dev/null
> > +++ b/drivers/soc/brcmstb/wktmr.c
> > @@ -0,0 +1,242 @@
> > [...]
> > +
> > +static void brcmstb_waketmr_set_alarm(struct brcmstb_waketmr *timer,
> > + unsigned int secs)
> > +{
> > + unsigned int t;
>
> Use u32.

Sure.

> > +
> > + brcmstb_waketmr_clear_alarm(timer);
> > +
> > + t = readl_relaxed(timer->base + BRCMSTB_WKTMR_COUNTER);
> > + writel_relaxed(t + secs + 1, timer->base + BRCMSTB_WKTMR_ALARM);
> > +}
> > +
> > [...]
> > +static int brcmstb_waketmr_probe(struct platform_device *pdev)
> > +{
> > [...]
> > + /*
> > + * Set wakeup capability before requesting wakeup interrupt, so we can
> > + * process boot-time "wakeups" (e.g., from S5 soft-off)
> > + */
> > + device_set_wakeup_capable(dev, true);
> > + device_wakeup_enable(dev);
> > +
> > + timer->irq = platform_get_irq(pdev, 0);
> > + if ((int)timer->irq < 0)
>
> Probably better to just have timer->irq be a signed int so you don't
> need this cast.

That's the only place where it needs to be signed. All other APIs are
unsigned, I think. But sure, I can change that.

> > [snip]
>
> Acked-by: Gregory Fong <gregory.0xf0@xxxxxxxxx>

Thanks for the review!

Brian
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