Re: [PATCHv3] x86, mrst: share APB timer code with other platforms

From: Jamie Iles
Date: Mon May 09 2011 - 16:50:24 EST


On Mon, May 09, 2011 at 01:22:22PM -0700, john stultz wrote:
> On Tue, 2011-04-12 at 12:10 +0100, Jamie Iles wrote:
> > The APB timers are an IP block from Synopsys (DesignWare APB timers)
> > and are also found in other systems including ARM SoC's. This patch
> > adds functions for creating clock_event_devices and clocksources from
> > APB timers but does not do the resource allocation. This is handled
> > in a higher layer to allow the timers to be created from multiple
> > methods such as platform_devices.
> >
> > Changes since v2:
> > - Make eoi() for clock_event_device optional for x86 where eoi
> > is handled in firmware.
> > Changes since v1:
> > - Use the correct timer for clocksource on x86
> > - Select the correct timer rating for x86
> > - Restore freerunning timer behaviour for oneshot event devices
> > - Reenable event irq correctly for hotplug
>
> Sorry for being slow to review this.

No worries, appreciate the review.

> Just a minor nit below.
>
> > +struct dw_apb_clocksource *
> > +dw_apb_clocksource_init(unsigned rating, char *name, void __iomem *base,
> > + unsigned long freq)
> > +{
> > + struct dw_apb_clocksource *dw_cs = kzalloc(sizeof(*dw_cs), GFP_KERNEL);
> > +
> > + if (!dw_cs)
> > + return NULL;
> > +
> > + dw_cs->timer.base = base;
> > + dw_cs->timer.freq = freq;
> > + dw_cs->cs.name = name;
> > + dw_cs->cs.rating = rating;
> > + dw_cs->cs.read = __apbt_read_clocksource;
> > + dw_cs->cs.mask = CLOCKSOURCE_MASK(32);
> > + dw_cs->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
> > + dw_cs->cs.resume = apbt_restart_clocksource;
> > +
> > + return dw_cs;
> > +}
>
> So I don't see anything that frees the dw_apb_clocksource structure
> after it has been allocated. Should this instead be allocated by the
> caller and passed in to be initialized here?

Yeah, either that or I could add a dw_apb_clocksource_remove() that does
the clocksource_unregister() and kfree(). That's probably a little more
consistent with the rest of the driver.

Jamie
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/