2023-01-16 15:36:02

by Pierluigi Passaro

Subject: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

Both the functions gpiochip_request_own_desc and
gpiochip_free_own_desc are exported from
drivers/gpio/gpiolib.c
but this file is compiled only when CONFIG_GPIOLIB is enabled.
Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
reasonable definitions in the "#else" branch.

Signed-off-by: Pierluigi Passaro <[email protected]>
Reported-by: kernel test robot <[email protected]>
---
include/linux/gpio/driver.h | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 44783fc16125..ed77c6fc0beb 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -758,6 +758,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *gc)

#endif /* CONFIG_PINCTRL */

+#ifdef CONFIG_GPIOLIB
+
struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
unsigned int hwnum,
const char *label,
@@ -765,8 +767,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
enum gpiod_flags dflags);
void gpiochip_free_own_desc(struct gpio_desc *desc);

-#ifdef CONFIG_GPIOLIB
-
/* lock/unlock as IRQ */
int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
@@ -776,6 +776,22 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);

#else /* CONFIG_GPIOLIB */

+static inline struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
+ unsigned int hwnum,
+ const char *label,
+ enum gpio_lookup_flags lflags,
+ enum gpiod_flags dflags)
+{
+ /* GPIO can never have been requested */
+ WARN_ON(1);
+ return ERR_PTR(-ENODEV);
+}
+
+static inline void gpiochip_free_own_desc(struct gpio_desc *desc)
+{
+ WARN_ON(1);
+}
+
static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
{
/* GPIO can never have been requested */
--
2.37.2

2023-01-17 06:40:38

by Alexander Stein

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

Hi,

Am Montag, 16. Januar 2023, 15:08:11 CET schrieb Pierluigi Passaro:
> Both the functions gpiochip_request_own_desc and
> gpiochip_free_own_desc are exported from
> drivers/gpio/gpiolib.c
> but this file is compiled only when CONFIG_GPIOLIB is enabled.
> Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> reasonable definitions in the "#else" branch.
>
> Signed-off-by: Pierluigi Passaro <[email protected]>
> Reported-by: kernel test robot <[email protected]>
> ---
> include/linux/gpio/driver.h | 20 ++++++++++++++++++--
> 1 file changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
> index 44783fc16125..ed77c6fc0beb 100644
> --- a/include/linux/gpio/driver.h
> +++ b/include/linux/gpio/driver.h
> @@ -758,6 +758,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *gc)
>
> #endif /* CONFIG_PINCTRL */
>
> +#ifdef CONFIG_GPIOLIB
> +
> struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> unsigned int hwnum,
> const char *label,
> @@ -765,8 +767,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct
> gpio_chip *gc, enum gpiod_flags dflags);
> void gpiochip_free_own_desc(struct gpio_desc *desc);
>
> -#ifdef CONFIG_GPIOLIB
> -
> /* lock/unlock as IRQ */
> int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
> void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
> @@ -776,6 +776,22 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc
> *desc);
>
> #else /* CONFIG_GPIOLIB */
>
> +static inline struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip
> *gc, + unsigned int hwnum,
> + const char *label,
> + enum gpio_lookup_flags
lflags,
> + enum gpiod_flags dflags)
> +{
> + /* GPIO can never have been requested */
> + WARN_ON(1);

This will raise the warning on each invocation. How about using
WARN_ON_ONCE(1), or even WARN_ONCE("Kernel compiled without CONFIG_GPIOLIB
support")?

> + return ERR_PTR(-ENODEV);
> +}
> +
> +static inline void gpiochip_free_own_desc(struct gpio_desc *desc)
> +{
> + WARN_ON(1);

Same as above.

Best regards,
Alexander

> +}
> +
> static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
> {
> /* GPIO can never have been requested */

2023-01-17 07:51:48

by Pierluigi Passaro

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

On Tue, Jan 17, 2023 at 7:23 AM Alexander Stein <[email protected]> wrote:
> Hi,
>
> Am Montag, 16. Januar 2023, 15:08:11 CET schrieb Pierluigi Passaro:
> > Both the functions gpiochip_request_own_desc and
> > gpiochip_free_own_desc are exported from
> > ? ? drivers/gpio/gpiolib.c
> > but this file is compiled only when CONFIG_GPIOLIB is enabled.
> > Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> > reasonable definitions in the "#else" branch.
> >
> > Signed-off-by: Pierluigi Passaro <[email protected]>
> > Reported-by: kernel test robot <[email protected]>
> > ---
> > ?include/linux/gpio/driver.h | 20 ++++++++++++++++++--
> > ?1 file changed, 18 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
> > index 44783fc16125..ed77c6fc0beb 100644
> > --- a/include/linux/gpio/driver.h
> > +++ b/include/linux/gpio/driver.h
> > @@ -758,6 +758,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *gc)
> >
> > ?#endif /* CONFIG_PINCTRL */
> >
> > +#ifdef CONFIG_GPIOLIB
> > +
> > ?struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned int hwnum,
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? const char *label,
> > @@ -765,8 +767,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct
> > gpio_chip *gc, enum gpiod_flags dflags);
> > ?void gpiochip_free_own_desc(struct gpio_desc *desc);
> >
> > -#ifdef CONFIG_GPIOLIB
> > -
> > ?/* lock/unlock as IRQ */
> > ?int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
> > ?void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
> > @@ -776,6 +776,22 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc
> > *desc);
> >
> > ?#else /* CONFIG_GPIOLIB */
> >
> > +static inline struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip
> > *gc, + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?unsigned int hwnum,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? const char *label,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? enum gpio_lookup_flags
> lflags,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? enum gpiod_flags dflags)
> > +{
> > + ? ? /* GPIO can never have been requested */
> > + ? ? WARN_ON(1);
>
> This will raise the warning on each invocation. How about using
> WARN_ON_ONCE(1), or even WARN_ONCE("Kernel compiled without CONFIG_GPIOLIB
> support")?
>
No problem on my side, but this would create a misalignment with all other
GPIOLIB "dummy" calls.
Personally I would prefer WARN_ONCE("Kernel compiled without CONFIG_GPIOLIB
support").
Please confirm your preferences and I'll provide a patch v2.
Thanks
>
> > + ? ? return ERR_PTR(-ENODEV);
> > +}
> > +
> > +static inline void gpiochip_free_own_desc(struct gpio_desc *desc)
> > +{
> > + ? ? WARN_ON(1);
>
> Same as above.
>
> Best regards,
> Alexander
>
> > +}
> > +
> > ?static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
> > {
> > ? ? ? /* GPIO can never have been requested */

2023-01-17 10:06:59

by Bartosz Golaszewski

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

On Mon, Jan 16, 2023 at 3:08 PM Pierluigi Passaro
<[email protected]> wrote:
>
> Both the functions gpiochip_request_own_desc and
> gpiochip_free_own_desc are exported from
> drivers/gpio/gpiolib.c
> but this file is compiled only when CONFIG_GPIOLIB is enabled.
> Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> reasonable definitions in the "#else" branch.
>
> Signed-off-by: Pierluigi Passaro <[email protected]>
> Reported-by: kernel test robot <[email protected]>

Please add a Fixes tag.

Bart

> ---
> include/linux/gpio/driver.h | 20 ++++++++++++++++++--
> 1 file changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
> index 44783fc16125..ed77c6fc0beb 100644
> --- a/include/linux/gpio/driver.h
> +++ b/include/linux/gpio/driver.h
> @@ -758,6 +758,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *gc)
>
> #endif /* CONFIG_PINCTRL */
>
> +#ifdef CONFIG_GPIOLIB
> +
> struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> unsigned int hwnum,
> const char *label,
> @@ -765,8 +767,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> enum gpiod_flags dflags);
> void gpiochip_free_own_desc(struct gpio_desc *desc);
>
> -#ifdef CONFIG_GPIOLIB
> -
> /* lock/unlock as IRQ */
> int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
> void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
> @@ -776,6 +776,22 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
>
> #else /* CONFIG_GPIOLIB */
>
> +static inline struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> + unsigned int hwnum,
> + const char *label,
> + enum gpio_lookup_flags lflags,
> + enum gpiod_flags dflags)
> +{
> + /* GPIO can never have been requested */
> + WARN_ON(1);
> + return ERR_PTR(-ENODEV);
> +}
> +
> +static inline void gpiochip_free_own_desc(struct gpio_desc *desc)
> +{
> + WARN_ON(1);
> +}
> +
> static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
> {
> /* GPIO can never have been requested */
> --
> 2.37.2
>

2023-01-17 10:30:17

by Bartosz Golaszewski

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

On Tue, Jan 17, 2023 at 8:44 AM Pierluigi Passaro
<[email protected]> wrote:
>
> On Tue, Jan 17, 2023 at 7:23 AM Alexander Stein <[email protected]> wrote:
> > Hi,
> >
> > Am Montag, 16. Januar 2023, 15:08:11 CET schrieb Pierluigi Passaro:
> > > Both the functions gpiochip_request_own_desc and
> > > gpiochip_free_own_desc are exported from
> > > drivers/gpio/gpiolib.c
> > > but this file is compiled only when CONFIG_GPIOLIB is enabled.
> > > Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> > > reasonable definitions in the "#else" branch.
> > >
> > > Signed-off-by: Pierluigi Passaro <[email protected]>
> > > Reported-by: kernel test robot <[email protected]>
> > > ---
> > > include/linux/gpio/driver.h | 20 ++++++++++++++++++--
> > > 1 file changed, 18 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
> > > index 44783fc16125..ed77c6fc0beb 100644
> > > --- a/include/linux/gpio/driver.h
> > > +++ b/include/linux/gpio/driver.h
> > > @@ -758,6 +758,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *gc)
> > >
> > > #endif /* CONFIG_PINCTRL */
> > >
> > > +#ifdef CONFIG_GPIOLIB
> > > +
> > > struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> > > unsigned int hwnum,
> > > const char *label,
> > > @@ -765,8 +767,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct
> > > gpio_chip *gc, enum gpiod_flags dflags);
> > > void gpiochip_free_own_desc(struct gpio_desc *desc);
> > >
> > > -#ifdef CONFIG_GPIOLIB
> > > -
> > > /* lock/unlock as IRQ */
> > > int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
> > > void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
> > > @@ -776,6 +776,22 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc
> > > *desc);
> > >
> > > #else /* CONFIG_GPIOLIB */
> > >
> > > +static inline struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip
> > > *gc, + unsigned int hwnum,
> > > + const char *label,
> > > + enum gpio_lookup_flags
> > lflags,
> > > + enum gpiod_flags dflags)
> > > +{
> > > + /* GPIO can never have been requested */
> > > + WARN_ON(1);
> >
> > This will raise the warning on each invocation. How about using
> > WARN_ON_ONCE(1), or even WARN_ONCE("Kernel compiled without CONFIG_GPIOLIB
> > support")?
> >
> No problem on my side, but this would create a misalignment with all other
> GPIOLIB "dummy" calls.
> Personally I would prefer WARN_ONCE("Kernel compiled without CONFIG_GPIOLIB
> support").
> Please confirm your preferences and I'll provide a patch v2.
> Thanks
> >
> > > + return ERR_PTR(-ENODEV);
> > > +}
> > > +
> > > +static inline void gpiochip_free_own_desc(struct gpio_desc *desc)
> > > +{
> > > + WARN_ON(1);
> >
> > Same as above.
> >
> > Best regards,
> > Alexander
> >
> > > +}
> > > +
> > > static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
> > > {
> > > /* GPIO can never have been requested */

If someone calls these functions without GPIOLIB enabled then they
deserve lots of warnings to remind them to fix their config. :)

Let's keep it like in other places.

Bart

2023-01-17 10:30:57

by Pierluigi Passaro

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

On Tue, Jan 17, 2023 at 10:36 AM Bartosz Golaszewski <[email protected]> wrote:
> On Mon, Jan 16, 2023 at 3:08 PM Pierluigi Passaro
> <[email protected]> wrote:
> >
> > Both the functions gpiochip_request_own_desc and
> > gpiochip_free_own_desc are exported from
> > ? ? drivers/gpio/gpiolib.c
> > but this file is compiled only when CONFIG_GPIOLIB is enabled.
> > Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> > reasonable definitions in the "#else" branch.
> >
> > Signed-off-by: Pierluigi Passaro <[email protected]>
> > Reported-by: kernel test robot <[email protected]>
>
> Please add a Fixes tag.
>
I beg your pardon for the question: how can I "add a Fixes tag" ?
Can you point me to any reference documentation / instructions ?
Thanks
>
> Bart
>
> > ---
> > ?include/linux/gpio/driver.h | 20 ++++++++++++++++++--
> > ?1 file changed, 18 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
> > index 44783fc16125..ed77c6fc0beb 100644
> > --- a/include/linux/gpio/driver.h
> > +++ b/include/linux/gpio/driver.h
> > @@ -758,6 +758,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *gc)
> >
> > ?#endif /* CONFIG_PINCTRL */
> >
> > +#ifdef CONFIG_GPIOLIB
> > +
> > ?struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned int hwnum,
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? const char *label,
> > @@ -765,8 +767,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? enum gpiod_flags dflags);
> > ?void gpiochip_free_own_desc(struct gpio_desc *desc);
> >
> > -#ifdef CONFIG_GPIOLIB
> > -
> > ?/* lock/unlock as IRQ */
> > ?int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
> > ?void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
> > @@ -776,6 +776,22 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
> >
> > ?#else /* CONFIG_GPIOLIB */
> >
> > +static inline struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned int hwnum,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? const char *label,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? enum gpio_lookup_flags lflags,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? enum gpiod_flags dflags)
> > +{
> > + ? ? ? /* GPIO can never have been requested */
> > + ? ? ? WARN_ON(1);
> > + ? ? ? return ERR_PTR(-ENODEV);
> > +}
> > +
> > +static inline void gpiochip_free_own_desc(struct gpio_desc *desc)
> > +{
> > + ? ? ? WARN_ON(1);
> > +}
> > +
> > ?static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
> > ?{
> > ? ? ? ? /* GPIO can never have been requested */
> > --
> > 2.37.2
> >

2023-01-18 14:58:20

by Bartosz Golaszewski

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

On Tue, Jan 17, 2023 at 11:17 AM Pierluigi Passaro
<[email protected]> wrote:
>
> On Tue, Jan 17, 2023 at 10:36 AM Bartosz Golaszewski <[email protected]> wrote:
> > On Mon, Jan 16, 2023 at 3:08 PM Pierluigi Passaro
> > <[email protected]> wrote:
> > >
> > > Both the functions gpiochip_request_own_desc and
> > > gpiochip_free_own_desc are exported from
> > > drivers/gpio/gpiolib.c
> > > but this file is compiled only when CONFIG_GPIOLIB is enabled.
> > > Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> > > reasonable definitions in the "#else" branch.
> > >
> > > Signed-off-by: Pierluigi Passaro <[email protected]>
> > > Reported-by: kernel test robot <[email protected]>
> >
> > Please add a Fixes tag.
> >
> I beg your pardon for the question: how can I "add a Fixes tag" ?
> Can you point me to any reference documentation / instructions ?
> Thanks
> >

Look at the output of `git blame` on the file in question and see who
added the changes that introduced the problem. Then, before your
Sign-off in the git message add: Fixes: <12 chars of the commit hash>
("<commit subject>"). See Existing commits with fixes for reference.

Bart

2023-01-21 01:07:02

by Pierluigi Passaro

Subject: Re: [PATCH] gpiolib: fix linker errors when GPIOLIB is disabled

On Wed, Jan 18, 2023 at 3:22 PM Bartosz Golaszewski <[email protected]> wrote:
> On Tue, Jan 17, 2023 at 11:17 AM Pierluigi Passaro
> <[email protected]> wrote:
> >
> > On Tue, Jan 17, 2023 at 10:36 AM Bartosz Golaszewski <[email protected]> wrote:
> > > On Mon, Jan 16, 2023 at 3:08 PM Pierluigi Passaro
> > > <[email protected]> wrote:
> > > >
> > > > Both the functions gpiochip_request_own_desc and
> > > > gpiochip_free_own_desc are exported from
> > > > drivers/gpio/gpiolib.c
> > > > but this file is compiled only when CONFIG_GPIOLIB is enabled.
> > > > Move the protototypes under "#ifdef CONFIG_GPIOLIB" and provide
> > > > reasonable definitions in the "#else" branch.
> > > >
> > > > Signed-off-by: Pierluigi Passaro <[email protected]>
> > > > Reported-by: kernel test robot <[email protected]>
> > >
> > > Please add a Fixes tag.
> > >
> > I beg your pardon for the question: how can I "add a Fixes tag" ?
> > Can you point me to any reference documentation / instructions ?
> > Thanks
> > >
>
> Look at the output of `git blame` on the file in question and see who
> added the changes that introduced the problem. Then, before your
> Sign-off in the git message add: Fixes: <12 chars of the commit hash>
> ("<commit subject>"). See Existing commits with fixes for reference.
>
> Bart
>
Thanks for the guidelines: I've just sent patch v2 with Fixes tag.