When CONFIG_OF is disabled then the matching table is not referenced and
the following warning appears:
drivers/clk/ralink/clk-mtmips.c:821:34: warning: unused variable 'mtmips_of_match' [-Wunused-const-variable]
821 | static const struct of_device_id mtmips_of_match[] = {
| ^
Silence it declaring 'mtmips_of_match' with '__maybe_unused'.
Fixes: 6f3b15586eef ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Sergio Paracuellos <[email protected]>
---
drivers/clk/ralink/clk-mtmips.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/clk/ralink/clk-mtmips.c b/drivers/clk/ralink/clk-mtmips.c
index 1e7991439527..6716394b28a3 100644
--- a/drivers/clk/ralink/clk-mtmips.c
+++ b/drivers/clk/ralink/clk-mtmips.c
@@ -820,7 +820,7 @@ static const struct mtmips_clk_data mt76x8_clk_data = {
.num_clk_periph = ARRAY_SIZE(mt76x8_pherip_clks),
};
-static const struct of_device_id mtmips_of_match[] = {
+static const __maybe_unused struct of_device_id mtmips_of_match[] = {
{
.compatible = "ralink,rt2880-sysc",
.data = &rt2880_clk_data,
--
2.25.1
On Wed, Aug 02, 2023 at 02:26:43PM -0700, Nick Desaulniers wrote:
> On Wed, Aug 2, 2023 at 2:26 AM Sergio Paracuellos
> <[email protected]> wrote:
> >
> > When CONFIG_OF is disabled then the matching table is not referenced and
> > the following warning appears:
> >
> > drivers/clk/ralink/clk-mtmips.c:821:34: warning: unused variable 'mtmips_of_match' [-Wunused-const-variable]
> > 821 | static const struct of_device_id mtmips_of_match[] = {
> > | ^
> >
> > Silence it declaring 'mtmips_of_match' with '__maybe_unused'.
> >
> > Fixes: 6f3b15586eef ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
> > Reported-by: kernel test robot <[email protected]>
> > Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> > Signed-off-by: Sergio Paracuellos <[email protected]>
>
> I think this is fine; Arnd or Nathan do you have a preference? or thoughts here?
I do not have much of a preference either, I tend to agree with your
reasoning for preferring the #ifdef but '__maybe_unused' is relatively
easy to audit on a per-file basis and I think that is more common than
the '#ifdef CONFIG_OF'.
Small nit, I think __maybe_unused typically goes between the variable
name and equals, like
static const struct of_device_id mtmips_of_match[] __maybe_unused = {
but this is obviously fine. Regardless:
Reviewed-by: Nathan Chancellor <[email protected]>
> If not, thanks for the patch.
> Reviewed-by: Nick Desaulniers <[email protected]>
>
> (I have a slight preference for wrapping the use in `#ifdef CONFIG_OF`
> since with the approach used by this patch, if all users are removed
> we will never get a warning for this var. But it's a weak preference;
> it's more important to me that we don't have -Werror promote this
> warning to a build breakage)
>
> > ---
> > drivers/clk/ralink/clk-mtmips.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/clk/ralink/clk-mtmips.c b/drivers/clk/ralink/clk-mtmips.c
> > index 1e7991439527..6716394b28a3 100644
> > --- a/drivers/clk/ralink/clk-mtmips.c
> > +++ b/drivers/clk/ralink/clk-mtmips.c
> > @@ -820,7 +820,7 @@ static const struct mtmips_clk_data mt76x8_clk_data = {
> > .num_clk_periph = ARRAY_SIZE(mt76x8_pherip_clks),
> > };
> >
> > -static const struct of_device_id mtmips_of_match[] = {
> > +static const __maybe_unused struct of_device_id mtmips_of_match[] = {
> > {
> > .compatible = "ralink,rt2880-sysc",
> > .data = &rt2880_clk_data,
> > --
> > 2.25.1
> >
>
>
> --
> Thanks,
> ~Nick Desaulniers
On Wed, Aug 2, 2023, at 23:26, Nick Desaulniers wrote:
> On Wed, Aug 2, 2023 at 2:26 AM Sergio Paracuellos <[email protected]> wrote:
>>
>> When CONFIG_OF is disabled then the matching table is not referenced and
>> the following warning appears:
>>
>> drivers/clk/ralink/clk-mtmips.c:821:34: warning: unused variable 'mtmips_of_match' [-Wunused-const-variable]
>> 821 | static const struct of_device_id mtmips_of_match[] = {
>> | ^
>>
>> Silence it declaring 'mtmips_of_match' with '__maybe_unused'.
>>
>> Fixes: 6f3b15586eef ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
>> Reported-by: kernel test robot <[email protected]>
>> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
>> Signed-off-by: Sergio Paracuellos <[email protected]>
>
> I think this is fine; Arnd or Nathan do you have a preference? or thoughts here?
>
> If not, thanks for the patch.
> Reviewed-by: Nick Desaulniers <[email protected]>
>
> (I have a slight preference for wrapping the use in `#ifdef CONFIG_OF`
> since with the approach used by this patch, if all users are removed
> we will never get a warning for this var. But it's a weak preference;
> it's more important to me that we don't have -Werror promote this
> warning to a build breakage)
I don't understand why there are two match tables in the same
driver, with almost the same contents. I have not looked very
closely here, but why can't we just drop the mtmips_clk_of_match[]
table (the one without the .data fields) and use the same
table for both? Is this because of the ralink,rt2880-reset entry
that is missing in mtmips_of_match, or is that another bug?
I also see that there is both a platform_driver instance for
late probing and a list of CLK_OF_DECLARE_DRIVER() entries.
Do we need both here?
Arnd
On Wed, Aug 2, 2023 at 2:26 AM Sergio Paracuellos
<[email protected]> wrote:
>
> When CONFIG_OF is disabled then the matching table is not referenced and
> the following warning appears:
>
> drivers/clk/ralink/clk-mtmips.c:821:34: warning: unused variable 'mtmips_of_match' [-Wunused-const-variable]
> 821 | static const struct of_device_id mtmips_of_match[] = {
> | ^
>
> Silence it declaring 'mtmips_of_match' with '__maybe_unused'.
>
> Fixes: 6f3b15586eef ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
> Reported-by: kernel test robot <[email protected]>
> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> Signed-off-by: Sergio Paracuellos <[email protected]>
I think this is fine; Arnd or Nathan do you have a preference? or thoughts here?
If not, thanks for the patch.
Reviewed-by: Nick Desaulniers <[email protected]>
(I have a slight preference for wrapping the use in `#ifdef CONFIG_OF`
since with the approach used by this patch, if all users are removed
we will never get a warning for this var. But it's a weak preference;
it's more important to me that we don't have -Werror promote this
warning to a build breakage)
> ---
> drivers/clk/ralink/clk-mtmips.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/ralink/clk-mtmips.c b/drivers/clk/ralink/clk-mtmips.c
> index 1e7991439527..6716394b28a3 100644
> --- a/drivers/clk/ralink/clk-mtmips.c
> +++ b/drivers/clk/ralink/clk-mtmips.c
> @@ -820,7 +820,7 @@ static const struct mtmips_clk_data mt76x8_clk_data = {
> .num_clk_periph = ARRAY_SIZE(mt76x8_pherip_clks),
> };
>
> -static const struct of_device_id mtmips_of_match[] = {
> +static const __maybe_unused struct of_device_id mtmips_of_match[] = {
> {
> .compatible = "ralink,rt2880-sysc",
> .data = &rt2880_clk_data,
> --
> 2.25.1
>
--
Thanks,
~Nick Desaulniers
On Thu, Aug 3, 2023, at 00:35, Sergio Paracuellos wrote:
> Hi Arnd.
>
> El El jue, 3 ago 2023 a las 0:02, Arnd Bergmann <[email protected]> escribió:
>> On Wed, Aug 2, 2023, at 23:26, Nick Desaulniers wrote:
>> > On Wed, Aug 2, 2023 at 2:26 AM Sergio Paracuellos <[email protected]> wrote:
>> >>
>> >> When CONFIG_OF is disabled then the matching table is not referenced and
>> >> the following warning appears:
>> >>
>> >> drivers/clk/ralink/clk-mtmips.c:821:34: warning: unused variable 'mtmips_of_match' [-Wunused-const-variable]
>> >> 821 | static const struct of_device_id mtmips_of_match[] = {
>> >> | ^
>> >>
>> >> Silence it declaring 'mtmips_of_match' with '__maybe_unused'.
>> >>
>> >> Fixes: 6f3b15586eef ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
>> >> Reported-by: kernel test robot <[email protected]>
>> >> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
>> >> Signed-off-by: Sergio Paracuellos <[email protected]>
>> >
>> > I think this is fine; Arnd or Nathan do you have a preference? or thoughts here?
>> >
>> > If not, thanks for the patch.
>> > Reviewed-by: Nick Desaulniers <[email protected]>
>> >
>> > (I have a slight preference for wrapping the use in `#ifdef CONFIG_OF`
>> > since with the approach used by this patch, if all users are removed
>> > we will never get a warning for this var. But it's a weak preference;
>> > it's more important to me that we don't have -Werror promote this
>> > warning to a build breakage)
>>
>> I don't understand why there are two match tables in the same
>> driver, with almost the same contents. I have not looked very
>> closely here, but why can't we just drop the mtmips_clk_of_match[]
>> table (the one without the .data fields) and use the same
>> table for both? Is this because of the ralink,rt2880-reset entry
>> that is missing in mtmips_of_match, or is that another bug?
>
> ralink,rt2880-reset is for old dts compatibility and only applies to
> reset driver. The one with data fields apply for clocks and is needed.
Ok, I see. It still looks like the two tables can simply be
merged by adding the ralink,rt2880-reset entry to mtmips_of_match[],
which will allow it to be used for mtmips_clk_driver (which doesn't
use the data) as well as for mtmips_clk_init() (which doesn't
need get called for ralink,rt2880-reset).
>> I also see that there is both a platform_driver instance for
>> late probing and a list of CLK_OF_DECLARE_DRIVER() entries.
>> Do we need both here?
>
> This system controller driver provide clock and reset controllers.
> Clock cannot be a platform driver since we need to set
> mips_hpr_frequency at a very early sargento. Reset stuff can be a
> platform driver so both of them are needed.
Arnd