Re: [PATCH 06/20] include: input: elan-i2c-ids: Mark 'elan_acpi_id' as __maybe_unused

From: Dmitry Torokhov
Date: Fri Nov 06 2020 - 02:28:19 EST


On Thu, Nov 05, 2020 at 09:13:05AM +0000, Lee Jones wrote:
> On Wed, 04 Nov 2020, Dmitry Torokhov wrote:
>
> > Hi Lee,
> >
> > On Wed, Nov 04, 2020 at 04:24:13PM +0000, Lee Jones wrote:
> > > Some drivers which include 'elan-i2c-ids.h' make use of
> > > 'elan_acpi_id', but not all do. Tell the compiler that this is
> > > expected behaviour.
> > >
> > > Fixes the following W=1 kernel build warning(s):
> > >
> > > include/linux/input/elan-i2c-ids.h:26:36: warning: ‘elan_acpi_id’ defined but not used [-Wunused-const-variable=]
> > >
> > > Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> > > Cc: dusonlin@xxxxxxxxxx
> > > Cc: KT Liao <kt.liao@xxxxxxxxxx>
> > > Cc: linux-input@xxxxxxxxxxxxxxx
> > > Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
> > > ---
> > > include/linux/input/elan-i2c-ids.h | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/include/linux/input/elan-i2c-ids.h b/include/linux/input/elan-i2c-ids.h
> > > index 520858d126808..b6976d99b6b75 100644
> > > --- a/include/linux/input/elan-i2c-ids.h
> > > +++ b/include/linux/input/elan-i2c-ids.h
> > > @@ -23,7 +23,7 @@
> > >
> > > #include <linux/mod_devicetable.h>
> > >
> > > -static const struct acpi_device_id elan_acpi_id[] = {
> > > +static const struct acpi_device_id __maybe_unused elan_acpi_id[] = {
> > > { "ELAN0000", 0 },
> > > { "ELAN0100", 0 },
> > > { "ELAN0600", 0 },
> >
> > I think I'd prefer something like this instead:
> >
> > diff --git a/drivers/input/mouse/elan_i2c_core.c
> > b/drivers/input/mouse/elan_i2c_core.c
> > index c599e21a8478..65d21a050cea 100644
> > --- a/drivers/input/mouse/elan_i2c_core.c
> > +++ b/drivers/input/mouse/elan_i2c_core.c
> > @@ -34,7 +34,6 @@
> > #include <linux/completion.h>
> > #include <linux/of.h>
> > #include <linux/property.h>
> > -#include <linux/input/elan-i2c-ids.h>
> > #include <linux/regulator/consumer.h>
> > #include <asm/unaligned.h>
> >
> > @@ -1413,6 +1412,7 @@ static const struct i2c_device_id elan_id[] = {
> > MODULE_DEVICE_TABLE(i2c, elan_id);
> >
> > #ifdef CONFIG_ACPI
> > +#include <linux/input/elan-i2c-ids.h>
> > MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
> > #endif
>
> Moving an #include file to the bottom of a source file, really?
>
> I can do as you wish, but it's a pretty 'interesting' solution. :)

I see absolutely nothing wrong with it, and if you check kernel sources
you will see #includes used this way.

What is your concern?

Thanks.

--
Dmitry