Re: [PATCH 1/2] power: reset: at91: add sama5d3 reset function

[Josh Wu]

On 7/10/2015 2:54 PM, Maxime Ripard wrote:
> On Fri, Jul 10, 2015 at 11:06:52AM +0800, Josh Wu wrote:
> > Hi, Maxime
> >
> > On 7/9/2015 8:03 PM, Maxime Ripard wrote:
> > > Hi,
> > >
> > > On Thu, Jul 09, 2015 at 06:15:46PM +0800, Josh Wu wrote:
> > > > As since sama5d3, to reset the chip, we don't need to shutdown the ddr
> > > > controller.
> > > >
> > > > So add a new compatible string and new restart function for sama5d3 and
> > > > later chips. As we don't use sama5d3 ddr controller, so remove it as
> > > > well.
> > > >
> > > > Signed-off-by: Josh Wu <josh.wu@xxxxxxxxx>
> > > > Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
> > > > ---
> > > >
> > > >   drivers/power/reset/at91-reset.c | 30 +++++++++++++++++++++---------
> > > >   1 file changed, 21 insertions(+), 9 deletions(-)
> > > >
> > > > diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
> > > > index 36dc52f..8944b63 100644
> > > > --- a/drivers/power/reset/at91-reset.c
> > > > +++ b/drivers/power/reset/at91-reset.c
> > > > @@ -123,6 +123,14 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
> > > >   	return NOTIFY_DONE;
> > > >   }
> > > > +static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
> > > > +			void *cmd)
> > > > +{
> > > > +	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST),
> > > > +				at91_rstc_base);
> > > > +	return NOTIFY_DONE;
> > > > +}
> > > > +
> > > >   static void __init at91_reset_status(struct platform_device *pdev)
> > > >   {
> > > >   	u32 reg = readl(at91_rstc_base + AT91_RSTC_SR);
> > > > @@ -155,13 +163,13 @@ static void __init at91_reset_status(struct platform_device *pdev)
> > > >   static const struct of_device_id at91_ramc_of_match[] = {
> > > >   	{ .compatible = "atmel,at91sam9260-sdramc", },
> > > >   	{ .compatible = "atmel,at91sam9g45-ddramc", },
> > > > -	{ .compatible = "atmel,sama5d3-ddramc", },
> > > >   	{ /* sentinel */ }
> > > >   };
> > > >   static const struct of_device_id at91_reset_of_match[] = {
> > > >   	{ .compatible = "atmel,at91sam9260-rstc", .data = at91sam9260_restart },
> > > >   	{ .compatible = "atmel,at91sam9g45-rstc", .data = at91sam9g45_restart },
> > > > +	{ .compatible = "atmel,sama5d3-rstc", .data = sama5d3_restart },
> > > >   	{ /* sentinel */ }
> > > >   };
> > > > @@ -181,17 +189,21 @@ static int at91_reset_of_probe(struct platform_device *pdev)
> > > >   		return -ENODEV;
> > > >   	}
> > > > -	for_each_matching_node(np, at91_ramc_of_match) {
> > > > -		at91_ramc_base[idx] = of_iomap(np, 0);
> > > > -		if (!at91_ramc_base[idx]) {
> > > > -			dev_err(&pdev->dev, "Could not map ram controller address\n");
> > > > -			return -ENODEV;
> > > > +	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
> > > > +	at91_restart_nb.notifier_call = match->data;
> > > > +
> > > > +	if (match->data != sama5d3_restart) {
> > > Using of_device_is_compatible seems more appropriate.
> > >
> > > Also, why are you changing the order of this loop and the notifier
> > > registration?
> > I moved this order because I use the match->data to compare whether is
> > sama5d3_restart. So I need to move this function (of_match_node) up.
> Ah right, my bad.
>
> Still, testing against the kernel pointer is not that great.
>
> It would be great to use something explicit instead, like
> of_device_is_compatible.

I agree. I will use of_device_is_compatible() in v2. And that can avoid 
the order change in the loop as well. Thanks.

Best Regards,
Josh Wu

> Maxime

--
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/