Re: [PATCH v6 1/2] iio: sx9310: Fix access to variable DT array

From: Alexandru Ardelean <ardeleanalex@gmail.com>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Gwendal Grignou <gwendal@chromium.org>,
	Jonathan Cameron <jic23@kernel.org>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Stephen Boyd <swboyd@chromium.org>,
	Daniel Campello <campello@chromium.org>,
	linux-iio <linux-iio@vger.kernel.org>
Subject: Re: [PATCH v6 1/2] iio: sx9310: Fix access to variable DT array
Date: Mon, 22 Mar 2021 17:16:44 +0200	[thread overview]
Message-ID: <CA+U=DsrMaQif+jC_PJixX=KKJ=t4Cqgn6cGUg6Dpdy8VtAviyw@mail.gmail.com> (raw)
In-Reply-To: <CAHp75VcULMoQaDh5YEcJjJV2n_zSH236A=465Nki8QxPZ4n0jQ@mail.gmail.com>

On Mon, Mar 22, 2021 at 3:29 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Mon, Mar 22, 2021 at 1:16 PM Alexandru Ardelean
> <ardeleanalex@gmail.com> wrote:
> > On Mon, Mar 22, 2021 at 9:33 AM Gwendal Grignou <gwendal@chromium.org> wrote:
>
> ...
>
> > but i think there may be a bug, in the fact that number of elements in
> > the array must be 4 (no more, no less)
> > that is, when reading the DT, it implies a variable array size of 1 to
> > 4, which doesn't seem true in the code;
> >
> > maybe a better idea would be to use of_property_read_***variable***_u32_array()
> > this would allow for a flexible array size;
>
> Wouldn't work in conjunction with the second patch.
> The above API is OF specific.

oh
good point

>
> >                count = of_property_read_variable_u32_array(np,
> > "semtech,combined-sensors",
> >                                            combined, 1,
> > ARRAY_SIZE(combined));   // min 1 , max 4 elements
> >                // count must be int, so that if it is negative, the
> > array doesn't loop;
> >                 for (i = 0; i < count; i++) {
> >                         if (combined[i] <= SX9310_NUM_CHANNELS)
> >                                 comb_mask |= BIT(combined[i]);
> >                 }
> >
>
> --
> With Best Regards,
> Andy Shevchenko