Re: [PATCH v5 4/4] thermal: Add Tegra SOCTHERM thermal management driver

[Mikko Perttunen <mikko.perttunen@kapsi.fi>]

On 09/24/2014 10:18 PM, Eduardo Valentin wrote:
>
> Mikko,
>
> On Thu, Aug 21, 2014 at 01:17:22PM +0300, Mikko Perttunen wrote:
>> ...
>> +
>> +static int enable_tsensor(struct tegra_soctherm *tegra,
>> +			  const struct tegra_tsensor *sensor,
>> +			  struct tsensor_shared_calibration shared)
>> +{
>> +	void * __iomem base = tegra->regs + sensor->base;
>
> I get sparse complaining about this declaration. For the sake of keeping
> a clean static checks, can you please:
> -       void * __iomem base = tegra->regs + sensor->base;
> +       void __iomem * base = tegra->regs + sensor->base;
>

Sure.

>
> Can you also please check the remaining sparse errors?
>    CHECK   drivers/thermal/tegra_soctherm.c
>    drivers/thermal/tegra_soctherm.c:260:43: warning: incorrect type in
>    initializer (different address spaces)
>    drivers/thermal/tegra_soctherm.c:260:43:    expected void *[noderef]
>    <asn:2>base
>    drivers/thermal/tegra_soctherm.c:260:43:    got void [noderef]
>    <asn:2>*
>    drivers/thermal/tegra_soctherm.c:271:9: warning: incorrect type in
>    argument 2 (different address spaces)
>    drivers/thermal/tegra_soctherm.c:271:9:    expected void volatile
>    [noderef] <asn:2>*addr
>    drivers/thermal/tegra_soctherm.c:271:9:    got void *
>    drivers/thermal/tegra_soctherm.c:279:9: warning: incorrect type in
>    argument 2 (different address spaces)
>    drivers/thermal/tegra_soctherm.c:279:9:    expected void volatile
>    [noderef] <asn:2>*addr
>    drivers/thermal/tegra_soctherm.c:279:9:    got void *
>    drivers/thermal/tegra_soctherm.c:281:9: warning: incorrect type in
>    argument 2 (different address spaces)
>    drivers/thermal/tegra_soctherm.c:281:9:    expected void volatile
>    [noderef] <asn:2>*addr
>    drivers/thermal/tegra_soctherm.c:281:9:    got void *
>    drivers/thermal/tegra_soctherm.c:347:25: warning: incorrect type in
>    argument 1 (different address spaces)
>    drivers/thermal/tegra_soctherm.c:347:25:    expected void const *ptr
>    drivers/thermal/tegra_soctherm.c:347:25:    got void [noderef]
>    <asn:2>*regs
>    drivers/thermal/tegra_soctherm.c:349:37: warning: incorrect type in
>    argument 1 (different address spaces)
>    drivers/thermal/tegra_soctherm.c:349:37:    expected void const *ptr
>    drivers/thermal/tegra_soctherm.c:349:37:    got void [noderef]
>    <asn:2>*regs
>    drivers/thermal/tegra_soctherm.c:271:9: warning: dereference of
>    noderef expression
>    drivers/thermal/tegra_soctherm.c:279:9: warning: dereference of
>    noderef expression
>    drivers/thermal/tegra_soctherm.c:281:9: warning: dereference of
>    noderef expression
>

Most of these seem to be caused by the above-mentioned swapping of 
__iomem and *. The ones on lines 347 and 349 are more peculiar, though. 
Apparently sparse doesn't like using IS_ERR and PTR_ERR on the void 
__iomem * pointer returned by devm_ioremap_resource. Looks like this has 
been discussed before (https://lkml.org/lkml/2013/6/17/216) and sparse 
should have been patched to ignore this situation, so I'm not sure why 
it's complaining about it. Anyway, there shouldn't be any issue here.

Mikko