Re: [PATCH v2 3/9] soc: samsung: Add Exynos Adaptive Supply Voltage driver

From: Krzysztof Kozlowski <krzk@kernel.org>
To: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: robh+dt@kernel.org, vireshk@kernel.org,
	devicetree@vger.kernel.org, kgene@kernel.org,
	pankaj.dubey@samsung.com,
	"linux-samsung-soc@vger.kernel.org"
	<linux-samsung-soc@vger.kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	linux-pm@vger.kernel.org,
	"Bartłomiej Żołnierkiewicz" <b.zolnierkie@samsung.com>,
	"Marek Szyprowski" <m.szyprowski@samsung.com>
Subject: Re: [PATCH v2 3/9] soc: samsung: Add Exynos Adaptive Supply Voltage driver
Date: Thu, 8 Aug 2019 14:31:39 +0200	[thread overview]
Message-ID: <CAJKOXPc8iFo=2JAGEZSC46N3sZae4+JcZYBCjpKysb6PFPzyaQ@mail.gmail.com> (raw)
In-Reply-To: <a56fe2d8-1f26-b462-1564-f23902f7dbb5@samsung.com>

On Thu, 8 Aug 2019 at 14:07, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote:
> >> +static unsigned int exynos5422_asv_parse_table(struct exynos_asv *asv,
> >> +                                     unsigned int pkg_id)
> >> +{
> >> +       return (pkg_id >> EXYNOS5422_TABLE_OFFSET) & EXYNOS5422_TABLE_MASK;
> >> +}
> >> +
> >> +static bool exynos5422_asv_parse_bin2(struct exynos_asv *asv,
> >> +                                    unsigned int pkg_id)
> >> +{
> >> +       return (pkg_id >> EXYNOS5422_BIN2_OFFSET) & EXYNOS5422_BIN2_MASK;
> >
> > return !!() for converting to boolean.
>
> I'm not convinced it is needed, the return type of the function is bool
> and value of the expression will be implicitly converted to that type.
> Is there any compiler warning related to that?

Yeah, but bool is int so there will be no implicit conversion... I
guess it is a convention. In theory !! is the proper conversion to
bool but if bool==int then it's essentially conversion to 1. I am not
sure what's the benefit, maybe for some wrong code which would do
comparisons on result like if (exynos5422_asv_parse_bin2() == TRUE)...

Best regards,
Krzysztof