Re: [PATCH v2] eeepc-laptop: simplify parse_arg()

From: Darren Hart
Date: Thu Sep 11 2014 - 18:37:53 EST


On Wed, Sep 10, 2014 at 10:05:20PM +0200, Paul Bolle wrote:
> parse_arg() has three possible return values:
> -EINVAL if sscanf(), in short, fails;
> zero if "count" is zero; and
> "count" in all other cases
>
> But "count" will never be zero. See, parse_arg() is called by the
> various store functions. And the callchain of these functions starts
> with sysfs_kf_write(). And that function checks for a zero "count". So
> we can stop checking for a zero "count", drop the "count" argument
> entirely, and transform parse_arg() into a function that returns zero on
> success or a negative error. That, in turn, allows to make those store
> functions just return "count" on success. The net effect is that the
> code becomes a bit easier to understand.
>
> While we're at it, let store_sys_acpi() return whatever error set_acpi()
> returns instead of remapping it to EIO.
>
> A nice side effect is that this GCC warning is silenced too:
> drivers/platform/x86/eeepc-laptop.c: In function âstore_sys_acpiâ:
> drivers/platform/x86/eeepc-laptop.c:279:10: warning: âvalueâ may be used uninitialized in this function [-Wmaybe-uninitialized]
> int rv, value;
>
> Which is, of course, the reason to have a look at parse_arg().
>
> Signed-off-by: Paul Bolle <pebolle@xxxxxxxxxx>

Queued, thanks Paul.

--
Darren Hart
Intel Open Source Technology Center
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