Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220415130005.85879-1-andrea.merello@gmail.com>
 <20220415130005.85879-13-andrea.merello@gmail.com> <20220415174808.3b81baa4@jic23-huawei>
 <CAHp75Ve_f2txO8izFzjFUCRiP6SkT2wVHshy5EtU8LGtjzDAkA@mail.gmail.com> <CAN8YU5PeDd8BQYHQVAzfkni_v55UjaJsRJ4ATs0FAVFt1KKX=g@mail.gmail.com>
In-Reply-To: <CAN8YU5PeDd8BQYHQVAzfkni_v55UjaJsRJ4ATs0FAVFt1KKX=g@mail.gmail.com>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Tue, 19 Apr 2022 11:29:59 +0300
Message-ID: <CAHp75VfENRuhUEp2Pj09qv6u-4Ze=GLwzCiSS+s2sTgt-aNE_g@mail.gmail.com>
Subject: Re: [v4 12/14] iio: imu: add BNO055 serdev driver
To:     Andrea Merello <andrea.merello@gmail.com>
Cc:     Jonathan Cameron <jic23@kernel.org>,
        Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
        linux-iio <linux-iio@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        devicetree <devicetree@vger.kernel.org>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Rob Herring <robh+dt@kernel.org>,
        Matt Ranostay <matt.ranostay@konsulko.com>,
        Alexandru Ardelean <ardeleanalex@gmail.com>,
        jmondi <jacopo@jmondi.org>,
        Andrea Merello <andrea.merello@iit.it>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, Apr 19, 2022 at 10:48 AM Andrea Merello
<andrea.merello@gmail.com> wrote:
> Il giorno sab 16 apr 2022 alle ore 10:45 Andy Shevchenko
> <andy.shevchenko@gmail.com> ha scritto:
> > On Fri, Apr 15, 2022 at 7:40 PM Jonathan Cameron <jic23@kernel.org> wrote:
> > > On Fri, 15 Apr 2022 15:00:03 +0200
> > > Andrea Merello <andrea.merello@gmail.com> wrote:

...

> > > > +CFLAGS_bno055_ser.o := -I$(src)
> > >
> > > Via a bit of grepping I can see other instances of this pattern which point out
> > > that it's to do with allowing the tracing framework to see trace.h.
> > > Perhaps a similar comment here would be good (if nothing else I doubt I'll
> > > remember why this magic is here in a few years time!)
> >
> > Can be done better way, see dwc3 or drivers/base/ trace point implementations.
>
> May you elaborate, please? It appears that both dwc3 and driver/base
> use this same trick of tweaking the CFLAGS in the Makefile in order to
> fix the header file thing. What I see is different is that they both
> use an (almost empty) trace.c file. Is this what you are suggesting?

There are two differences in your code:
1) no separate c module, which...
2) is built depending on CONFIG_TRACE.

Hence, no need to have a separate ugly config option.

-- 
With Best Regards,
Andy Shevchenko