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From:   Benjamin Tissoires <benjamin.tissoires@redhat.com>
Date:   Mon, 1 Mar 2021 15:27:22 +0100
Message-ID: <CAO-hwJLXAHvjYKxu8pyqMPCNgMrN-H8bGWudVqCaRFnWODHPVQ@mail.gmail.com>
Subject: Re: [PATCH 3/5] HID: core: Export some report item parsing functions.
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     =?UTF-8?Q?Ronald_Tschal=C3=A4r?= <ronald@innovation.ch>,
        Jiri Kosina <jikos@kernel.org>,
        Jonathan Cameron <jic23@kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Peter Meerwald-Stadler <pmeerw@pmeerw.net>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-input <linux-input@vger.kernel.org>,
        linux-iio <linux-iio@vger.kernel.org>
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On Mon, Mar 1, 2021 at 3:18 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Sun, Feb 28, 2021 at 3:30 AM Ronald Tschal=C3=A4r <ronald@innovation.c=
h> wrote:
> >
> > These are useful to drivers that need to scan or parse reports
> > themselves.
>
> ...
>
> > -       while ((start =3D fetch_item(start, end, &item)) !=3D NULL)
> > +       while ((start =3D hid_fetch_item(start, end, &item)) !=3D NULL)
> >                 dispatch_type[item.type](parser, &item);
>
> > -       while ((next =3D fetch_item(start, end, &item)) !=3D NULL) {
> > +       while ((next =3D hid_fetch_item(start, end, &item)) !=3D NULL) =
{
> >                 start =3D next;
>
> I don't see the full picture, but perhaps you may also introduce
> for_each_hid_item() or so.

Same here, I don't see the full picture, but I would suggest to not
export those functions at all.

From 4/5, I can see that you are using them in
appleib_find_collection(), which is only called by
appleib_add_device(), which in turn is always called with a parsed and
started HID device. Why can you not rely on the core parsing and
iterate over the already parsed hid_field?

Cheers,
Benjamin