[PATCH 0/2] linux/kconfig.h: move IF_ENABLED() out of <linux/kconfig.h>

[PATCH 0/2] linux/kconfig.h: move IF_ENABLED() out of <linux/kconfig.h>

[Masahiro Yamada]

I insist on <linux/kconfig.h> having only minimal set of macros
that are needed to evaluate CONFIG options.

Everytime somebody added an alien to <linux/kconfig.h>, I needed to
kick it out.

I did not notice 1b399bb04837183cecdc1b32ef1cfc7fcfa75d32 because
I was not addressed by [1].

[1]: https://lore.kernel.org/lkml/?q=kconfig.h%3A+Add+IF_ENABLED%28%29+macro

I like Paul's idea, but if I had noticed the patch in time, I would
have tried my best to persuade to implement it outside of <linux/kconfig.h>
(Paul's initial patch was adding it to a new header instead of <linux/kconfig.h>)

Before it is widely used, I want to fix it.

In 2/2, I converted pm.h to allow driver cleanups.



Masahiro Yamada (2):
  linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in
    <linux/kernel.h>
  pm: allow drivers to drop #ifdef and __maybe_unused from pm callbacks

 drivers/pinctrl/pinctrl-ingenic.c | 20 ++++-----
 include/linux/kconfig.h           |  6 ---
 include/linux/kernel.h            |  2 +
 include/linux/pm.h                | 67 +++++++++++--------------------
 4 files changed, 36 insertions(+), 59 deletions(-)

-- 
2.27.0

[PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

[Masahiro Yamada]

<linux/kconfig.h> is included from all the kernel-space source files,
including C, assembly, linker scripts. It is intended to contain minimal
set of macros to evaluate CONFIG options.

IF_ENABLED() is an intruder here because (x ? y : z) is C code, which
should not be included from assembly files or linker scripts.

Also, <linux/kconfig.h> is no longer self-contained because NULL is
defined in <linux/stddef.h>.

Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().

PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
sub-systems often define dedicated macros such as of_match_ptr(),
pm_ptr() etc. for common use-cases.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 drivers/pinctrl/pinctrl-ingenic.c | 20 ++++++++++----------
 include/linux/kconfig.h           |  6 ------
 include/linux/kernel.h            |  2 ++
 3 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-ingenic.c b/drivers/pinctrl/pinctrl-ingenic.c
index f2746125b077..b21e2ae4528d 100644
--- a/drivers/pinctrl/pinctrl-ingenic.c
+++ b/drivers/pinctrl/pinctrl-ingenic.c
@@ -2496,43 +2496,43 @@ static int __init ingenic_pinctrl_probe(struct platform_device *pdev)
 static const struct of_device_id ingenic_pinctrl_of_match[] = {
 	{
 		.compatible = "ingenic,jz4740-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_JZ4740, &jz4740_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4740), &jz4740_chip_info)
 	},
 	{
 		.compatible = "ingenic,jz4725b-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_JZ4725B, &jz4725b_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4725B), &jz4725b_chip_info)
 	},
 	{
 		.compatible = "ingenic,jz4760-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_JZ4760, &jz4760_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), &jz4760_chip_info)
 	},
 	{
 		.compatible = "ingenic,jz4760b-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_JZ4760, &jz4760_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), &jz4760_chip_info)
 	},
 	{
 		.compatible = "ingenic,jz4770-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_JZ4770, &jz4770_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4770), &jz4770_chip_info)
 	},
 	{
 		.compatible = "ingenic,jz4780-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_JZ4780, &jz4780_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4780), &jz4780_chip_info)
 	},
 	{
 		.compatible = "ingenic,x1000-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_X1000, &x1000_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), &x1000_chip_info)
 	},
 	{
 		.compatible = "ingenic,x1000e-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_X1000, &x1000_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), &x1000_chip_info)
 	},
 	{
 		.compatible = "ingenic,x1500-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_X1500, &x1500_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1500), &x1500_chip_info)
 	},
 	{
 		.compatible = "ingenic,x1830-pinctrl",
-		.data = IF_ENABLED(CONFIG_MACH_X1830, &x1830_chip_info)
+		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1830), &x1830_chip_info)
 	},
 	{ /* sentinel */ },
 };
diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
index 24a59cb06963..cc8fa109cfa3 100644
--- a/include/linux/kconfig.h
+++ b/include/linux/kconfig.h
@@ -70,10 +70,4 @@
  */
 #define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
 
-/*
- * IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO is set to 'y'
- * or 'm', NULL otherwise.
- */
-#define IF_ENABLED(option, ptr) (IS_ENABLED(option) ? (ptr) : NULL)
-
 #endif /* __LINUX_KCONFIG_H */
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 5b7ed6dc99ac..8685ca4cf287 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -38,6 +38,8 @@
 #define PTR_ALIGN_DOWN(p, a)	((typeof(p))ALIGN_DOWN((unsigned long)(p), (a)))
 #define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)
 
+#define PTR_IF(cond, ptr)	((cond) ? (ptr) : NULL)
+
 /* generic data direction definitions */
 #define READ			0
 #define WRITE			1
-- 
2.27.0

Re: [PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

[Paul Cercueil]

Hi Masahiro,

Le ven. 9 avril 2021 à 5:58, Masahiro Yamada <masahiroy@kernel.org> a 
écrit :
> <linux/kconfig.h> is included from all the kernel-space source files,
> including C, assembly, linker scripts. It is intended to contain 
> minimal
> set of macros to evaluate CONFIG options.
> 
> IF_ENABLED() is an intruder here because (x ? y : z) is C code, which
> should not be included from assembly files or linker scripts.
> 
> Also, <linux/kconfig.h> is no longer self-contained because NULL is
> defined in <linux/stddef.h>.
> 
> Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().
> 
> PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
> IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
> sub-systems often define dedicated macros such as of_match_ptr(),
> pm_ptr() etc. for common use-cases.

What's the idea behind changing IF_ENABLED() to PTR_IF()? You didn't 
explain that. What's wrong with IF_ENABLED()?

Cheers,
-Paul

> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> ---
> 
>  drivers/pinctrl/pinctrl-ingenic.c | 20 ++++++++++----------
>  include/linux/kconfig.h           |  6 ------
>  include/linux/kernel.h            |  2 ++
>  3 files changed, 12 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-ingenic.c 
> b/drivers/pinctrl/pinctrl-ingenic.c
> index f2746125b077..b21e2ae4528d 100644
> --- a/drivers/pinctrl/pinctrl-ingenic.c
> +++ b/drivers/pinctrl/pinctrl-ingenic.c
> @@ -2496,43 +2496,43 @@ static int __init 
> ingenic_pinctrl_probe(struct platform_device *pdev)
>  static const struct of_device_id ingenic_pinctrl_of_match[] = {
>  	{
>  		.compatible = "ingenic,jz4740-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_JZ4740, &jz4740_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4740), &jz4740_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,jz4725b-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_JZ4725B, &jz4725b_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4725B), &jz4725b_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,jz4760-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_JZ4760, &jz4760_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), &jz4760_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,jz4760b-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_JZ4760, &jz4760_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), &jz4760_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,jz4770-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_JZ4770, &jz4770_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4770), &jz4770_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,jz4780-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_JZ4780, &jz4780_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4780), &jz4780_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,x1000-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_X1000, &x1000_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), &x1000_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,x1000e-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_X1000, &x1000_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), &x1000_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,x1500-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_X1500, &x1500_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1500), &x1500_chip_info)
>  	},
>  	{
>  		.compatible = "ingenic,x1830-pinctrl",
> -		.data = IF_ENABLED(CONFIG_MACH_X1830, &x1830_chip_info)
> +		.data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1830), &x1830_chip_info)
>  	},
>  	{ /* sentinel */ },
>  };
> diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
> index 24a59cb06963..cc8fa109cfa3 100644
> --- a/include/linux/kconfig.h
> +++ b/include/linux/kconfig.h
> @@ -70,10 +70,4 @@
>   */
>  #define IS_ENABLED(option) __or(IS_BUILTIN(option), 
> IS_MODULE(option))
> 
> -/*
> - * IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO is 
> set to 'y'
> - * or 'm', NULL otherwise.
> - */
> -#define IF_ENABLED(option, ptr) (IS_ENABLED(option) ? (ptr) : NULL)
> -
>  #endif /* __LINUX_KCONFIG_H */
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index 5b7ed6dc99ac..8685ca4cf287 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -38,6 +38,8 @@
>  #define PTR_ALIGN_DOWN(p, a)	((typeof(p))ALIGN_DOWN((unsigned 
> long)(p), (a)))
>  #define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)
> 
> +#define PTR_IF(cond, ptr)	((cond) ? (ptr) : NULL)
> +
>  /* generic data direction definitions */
>  #define READ			0
>  #define WRITE			1
> --
> 2.27.0
> 

Re: [PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

[Masahiro Yamada]

On Fri, Apr 9, 2021 at 5:15 PM Paul Cercueil <paul@crapouillou.net> wrote:
>
> Hi Masahiro,
>
> Le ven. 9 avril 2021 à 5:58, Masahiro Yamada <masahiroy@kernel.org> a
> écrit :
> > <linux/kconfig.h> is included from all the kernel-space source files,
> > including C, assembly, linker scripts. It is intended to contain
> > minimal
> > set of macros to evaluate CONFIG options.
> >
> > IF_ENABLED() is an intruder here because (x ? y : z) is C code, which
> > should not be included from assembly files or linker scripts.
> >
> > Also, <linux/kconfig.h> is no longer self-contained because NULL is
> > defined in <linux/stddef.h>.
> >
> > Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().
> >
> > PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
> > IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
> > sub-systems often define dedicated macros such as of_match_ptr(),
> > pm_ptr() etc. for common use-cases.
>
> What's the idea behind changing IF_ENABLED() to PTR_IF()? You didn't
> explain that. What's wrong with IF_ENABLED()?


PTR_IF() is a more generalized variant, which I believe is
a better fit in <linux/kernel.h>
The first parameter does not need to be a CONFIG option,
but any expression.







> Cheers,
> -Paul
>
> > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> > ---
> >
> >  drivers/pinctrl/pinctrl-ingenic.c | 20 ++++++++++----------
> >  include/linux/kconfig.h           |  6 ------
> >  include/linux/kernel.h            |  2 ++
> >  3 files changed, 12 insertions(+), 16 deletions(-)
> >
> > diff --git a/drivers/pinctrl/pinctrl-ingenic.c
> > b/drivers/pinctrl/pinctrl-ingenic.c
> > index f2746125b077..b21e2ae4528d 100644
> > --- a/drivers/pinctrl/pinctrl-ingenic.c
> > +++ b/drivers/pinctrl/pinctrl-ingenic.c
> > @@ -2496,43 +2496,43 @@ static int __init
> > ingenic_pinctrl_probe(struct platform_device *pdev)
> >  static const struct of_device_id ingenic_pinctrl_of_match[] = {
> >       {
> >               .compatible = "ingenic,jz4740-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_JZ4740, &jz4740_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4740), &jz4740_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,jz4725b-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_JZ4725B, &jz4725b_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4725B), &jz4725b_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,jz4760-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_JZ4760, &jz4760_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), &jz4760_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,jz4760b-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_JZ4760, &jz4760_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), &jz4760_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,jz4770-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_JZ4770, &jz4770_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4770), &jz4770_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,jz4780-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_JZ4780, &jz4780_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4780), &jz4780_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,x1000-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_X1000, &x1000_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), &x1000_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,x1000e-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_X1000, &x1000_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), &x1000_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,x1500-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_X1500, &x1500_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1500), &x1500_chip_info)
> >       },
> >       {
> >               .compatible = "ingenic,x1830-pinctrl",
> > -             .data = IF_ENABLED(CONFIG_MACH_X1830, &x1830_chip_info)
> > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1830), &x1830_chip_info)
> >       },
> >       { /* sentinel */ },
> >  };
> > diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
> > index 24a59cb06963..cc8fa109cfa3 100644
> > --- a/include/linux/kconfig.h
> > +++ b/include/linux/kconfig.h
> > @@ -70,10 +70,4 @@
> >   */
> >  #define IS_ENABLED(option) __or(IS_BUILTIN(option),
> > IS_MODULE(option))
> >
> > -/*
> > - * IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO is
> > set to 'y'
> > - * or 'm', NULL otherwise.
> > - */
> > -#define IF_ENABLED(option, ptr) (IS_ENABLED(option) ? (ptr) : NULL)
> > -
> >  #endif /* __LINUX_KCONFIG_H */
> > diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> > index 5b7ed6dc99ac..8685ca4cf287 100644
> > --- a/include/linux/kernel.h
> > +++ b/include/linux/kernel.h
> > @@ -38,6 +38,8 @@
> >  #define PTR_ALIGN_DOWN(p, a) ((typeof(p))ALIGN_DOWN((unsigned
> > long)(p), (a)))
> >  #define IS_ALIGNED(x, a)             (((x) & ((typeof(x))(a) - 1)) == 0)
> >
> > +#define PTR_IF(cond, ptr)    ((cond) ? (ptr) : NULL)
> > +
> >  /* generic data direction definitions */
> >  #define READ                 0
> >  #define WRITE                        1
> > --
> > 2.27.0
> >
>
>


-- 
Best Regards
Masahiro Yamada

Re: [PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

[Andy Shevchenko]

On Fri, Apr 9, 2021 at 12:00 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> <linux/kconfig.h> is included from all the kernel-space source files,
> including C, assembly, linker scripts. It is intended to contain minimal

a minimal

> set of macros to evaluate CONFIG options.
>
> IF_ENABLED() is an intruder here because (x ? y : z) is C code, which
> should not be included from assembly files or linker scripts.
>
> Also, <linux/kconfig.h> is no longer self-contained because NULL is
> defined in <linux/stddef.h>.
>
> Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().
>
> PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
> IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
> sub-systems often define dedicated macros such as of_match_ptr(),
> pm_ptr() etc. for common use-cases.

>  include/linux/kernel.h            |  2 ++

Why kernel.h? Shouldn't it belong to a particular domain with a
respective header file?

Really what we have in the kernel.h right now is a complete train
wreck of something.
We have to define what exactly is kernel.h for?

Arnd? Others? Shall we start a wider discussion on the topic?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

[Paul Cercueil]

Le ven. 9 avril 2021 à 17:30, Masahiro Yamada <masahiroy@kernel.org> a 
écrit :
> On Fri, Apr 9, 2021 at 5:15 PM Paul Cercueil <paul@crapouillou.net> 
> wrote:
>> 
>>  Hi Masahiro,
>> 
>>  Le ven. 9 avril 2021 à 5:58, Masahiro Yamada 
>> <masahiroy@kernel.org> a
>>  écrit :
>>  > <linux/kconfig.h> is included from all the kernel-space source 
>> files,
>>  > including C, assembly, linker scripts. It is intended to contain
>>  > minimal
>>  > set of macros to evaluate CONFIG options.
>>  >
>>  > IF_ENABLED() is an intruder here because (x ? y : z) is C code, 
>> which
>>  > should not be included from assembly files or linker scripts.
>>  >
>>  > Also, <linux/kconfig.h> is no longer self-contained because NULL 
>> is
>>  > defined in <linux/stddef.h>.
>>  >
>>  > Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().
>>  >
>>  > PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
>>  > IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
>>  > sub-systems often define dedicated macros such as of_match_ptr(),
>>  > pm_ptr() etc. for common use-cases.
>> 
>>  What's the idea behind changing IF_ENABLED() to PTR_IF()? You didn't
>>  explain that. What's wrong with IF_ENABLED()?
> 
> 
> PTR_IF() is a more generalized variant, which I believe is
> a better fit in <linux/kernel.h>
> The first parameter does not need to be a CONFIG option,
> but any expression.

Fair enough, but we could still have IF_ENABLED as a specialized 
variant of PTR_IF:

#define IF_ENABLED(cfg, ptr) PTR_IF(IS_ENABLED(cfg), (ptr))

-Paul

> 
> 
>>  Cheers,
>>  -Paul
>> 
>>  > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
>>  > ---
>>  >
>>  >  drivers/pinctrl/pinctrl-ingenic.c | 20 ++++++++++----------
>>  >  include/linux/kconfig.h           |  6 ------
>>  >  include/linux/kernel.h            |  2 ++
>>  >  3 files changed, 12 insertions(+), 16 deletions(-)
>>  >
>>  > diff --git a/drivers/pinctrl/pinctrl-ingenic.c
>>  > b/drivers/pinctrl/pinctrl-ingenic.c
>>  > index f2746125b077..b21e2ae4528d 100644
>>  > --- a/drivers/pinctrl/pinctrl-ingenic.c
>>  > +++ b/drivers/pinctrl/pinctrl-ingenic.c
>>  > @@ -2496,43 +2496,43 @@ static int __init
>>  > ingenic_pinctrl_probe(struct platform_device *pdev)
>>  >  static const struct of_device_id ingenic_pinctrl_of_match[] = {
>>  >       {
>>  >               .compatible = "ingenic,jz4740-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_JZ4740, 
>> &jz4740_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4740), 
>> &jz4740_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,jz4725b-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_JZ4725B, 
>> &jz4725b_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4725B), 
>> &jz4725b_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,jz4760-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_JZ4760, 
>> &jz4760_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), 
>> &jz4760_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,jz4760b-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_JZ4760, 
>> &jz4760_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4760), 
>> &jz4760_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,jz4770-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_JZ4770, 
>> &jz4770_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4770), 
>> &jz4770_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,jz4780-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_JZ4780, 
>> &jz4780_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_JZ4780), 
>> &jz4780_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,x1000-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_X1000, 
>> &x1000_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), 
>> &x1000_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,x1000e-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_X1000, 
>> &x1000_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1000), 
>> &x1000_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,x1500-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_X1500, 
>> &x1500_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1500), 
>> &x1500_chip_info)
>>  >       },
>>  >       {
>>  >               .compatible = "ingenic,x1830-pinctrl",
>>  > -             .data = IF_ENABLED(CONFIG_MACH_X1830, 
>> &x1830_chip_info)
>>  > +             .data = PTR_IF(IS_ENABLED(CONFIG_MACH_X1830), 
>> &x1830_chip_info)
>>  >       },
>>  >       { /* sentinel */ },
>>  >  };
>>  > diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
>>  > index 24a59cb06963..cc8fa109cfa3 100644
>>  > --- a/include/linux/kconfig.h
>>  > +++ b/include/linux/kconfig.h
>>  > @@ -70,10 +70,4 @@
>>  >   */
>>  >  #define IS_ENABLED(option) __or(IS_BUILTIN(option),
>>  > IS_MODULE(option))
>>  >
>>  > -/*
>>  > - * IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO 
>> is
>>  > set to 'y'
>>  > - * or 'm', NULL otherwise.
>>  > - */
>>  > -#define IF_ENABLED(option, ptr) (IS_ENABLED(option) ? (ptr) : 
>> NULL)
>>  > -
>>  >  #endif /* __LINUX_KCONFIG_H */
>>  > diff --git a/include/linux/kernel.h b/include/linux/kernel.h
>>  > index 5b7ed6dc99ac..8685ca4cf287 100644
>>  > --- a/include/linux/kernel.h
>>  > +++ b/include/linux/kernel.h
>>  > @@ -38,6 +38,8 @@
>>  >  #define PTR_ALIGN_DOWN(p, a) ((typeof(p))ALIGN_DOWN((unsigned
>>  > long)(p), (a)))
>>  >  #define IS_ALIGNED(x, a)             (((x) & ((typeof(x))(a) - 
>> 1)) == 0)
>>  >
>>  > +#define PTR_IF(cond, ptr)    ((cond) ? (ptr) : NULL)
>>  > +
>>  >  /* generic data direction definitions */
>>  >  #define READ                 0
>>  >  #define WRITE                        1
>>  > --
>>  > 2.27.0
>>  >
>> 
>> 
> 
> 
> --
> Best Regards
> Masahiro Yamada

Re: [PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

[Masahiro Yamada]

On Fri, Apr 9, 2021 at 6:24 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Fri, Apr 9, 2021 at 12:00 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
> >
> > <linux/kconfig.h> is included from all the kernel-space source files,
> > including C, assembly, linker scripts. It is intended to contain minimal
>
> a minimal
>
> > set of macros to evaluate CONFIG options.
> >
> > IF_ENABLED() is an intruder here because (x ? y : z) is C code, which
> > should not be included from assembly files or linker scripts.
> >
> > Also, <linux/kconfig.h> is no longer self-contained because NULL is
> > defined in <linux/stddef.h>.
> >
> > Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().
> >
> > PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
> > IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
> > sub-systems often define dedicated macros such as of_match_ptr(),
> > pm_ptr() etc. for common use-cases.
>
> >  include/linux/kernel.h            |  2 ++
>
> Why kernel.h? Shouldn't it belong to a particular domain with a
> respective header file?
>
> Really what we have in the kernel.h right now is a complete train
> wreck of something.
> We have to define what exactly is kernel.h for?


<linux/kernel.h> contains random utility macros.

I did not find a good header to put it in otherwise.


>
> Arnd? Others? Shall we start a wider discussion on the topic?
>
> --
> With Best Regards,
> Andy Shevchenko


--
Best Regards
Masahiro Yamada