[PATCH] of: make for_each_property_of_node() available to to !OF

[PATCH] of: make for_each_property_of_node() available to to !OF

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

for_each_property_of_node() is a macro and so doesn't have a stub inline
function for !OF. Move it out of the relevant #ifdef to make it available
to all users.

Fixes: 611cad720148 ("dt: add of_alias_scan and of_alias_get_id")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
I have an upcoming driver that will use this but which can also be built
on non-DT systems. I'd like to get that in as a fix to avoid inter-tree
dependencies later.

 include/linux/of.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/of.h b/include/linux/of.h
index 6a9ddf20e79a..a3e8e429ad7f 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -362,9 +362,6 @@ extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
 						 int index);
 extern u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread);
 
-#define for_each_property_of_node(dn, pp) \
-	for (pp = dn->properties; pp != NULL; pp = pp->next)
-
 extern int of_n_addr_cells(struct device_node *np);
 extern int of_n_size_cells(struct device_node *np);
 extern const struct of_device_id *of_match_node(
@@ -892,6 +889,9 @@ static inline int of_prop_val_eq(struct property *p1, struct property *p2)
 	       !memcmp(p1->value, p2->value, (size_t)p1->length);
 }
 
+#define for_each_property_of_node(dn, pp) \
+	for (pp = dn->properties; pp != NULL; pp = pp->next)
+
 #if defined(CONFIG_OF) && defined(CONFIG_NUMA)
 extern int of_node_to_nid(struct device_node *np);
 #else
-- 
2.40.1

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Rob Herring]

On Sun, 03 Mar 2024 11:48:53 +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> for_each_property_of_node() is a macro and so doesn't have a stub inline
> function for !OF. Move it out of the relevant #ifdef to make it available
> to all users.
> 
> Fixes: 611cad720148 ("dt: add of_alias_scan and of_alias_get_id")
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> ---
> I have an upcoming driver that will use this but which can also be built
> on non-DT systems. I'd like to get that in as a fix to avoid inter-tree
> dependencies later.
> 
>  include/linux/of.h | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 

Applied, thanks!

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Geert Uytterhoeven]

Hi Bartosz,

On Sun, Mar 3, 2024 at 11:49 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> for_each_property_of_node() is a macro and so doesn't have a stub inline
> function for !OF. Move it out of the relevant #ifdef to make it available
> to all users.

Thanks for your patch, which is now commit ad8ee969d7e34dd3 ("of: make
for_each_property_of_node() available to to !OF") in dt-rh/for-next

> Fixes: 611cad720148 ("dt: add of_alias_scan and of_alias_get_id")

How is this related?

> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> ---
> I have an upcoming driver that will use this but which can also be built
> on non-DT systems. I'd like to get that in as a fix to avoid inter-tree
> dependencies later.

Do you have a link?

> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -362,9 +362,6 @@ extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
>                                                  int index);
>  extern u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread);
>
> -#define for_each_property_of_node(dn, pp) \
> -       for (pp = dn->properties; pp != NULL; pp = pp->next)
> -
>  extern int of_n_addr_cells(struct device_node *np);
>  extern int of_n_size_cells(struct device_node *np);
>  extern const struct of_device_id *of_match_node(
> @@ -892,6 +889,9 @@ static inline int of_prop_val_eq(struct property *p1, struct property *p2)
>                !memcmp(p1->value, p2->value, (size_t)p1->length);
>  }
>
> +#define for_each_property_of_node(dn, pp) \
> +       for (pp = dn->properties; pp != NULL; pp = pp->next)

Is this safe if !OF? Can dn be NULL?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Bartosz Golaszewski]

On Tue, Mar 5, 2024 at 9:32 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Bartosz,
>
> On Sun, Mar 3, 2024 at 11:49 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> >
> > for_each_property_of_node() is a macro and so doesn't have a stub inline
> > function for !OF. Move it out of the relevant #ifdef to make it available
> > to all users.
>
> Thanks for your patch, which is now commit ad8ee969d7e34dd3 ("of: make
> for_each_property_of_node() available to to !OF") in dt-rh/for-next
>
> > Fixes: 611cad720148 ("dt: add of_alias_scan and of_alias_get_id")
>
> How is this related?
>

This commit added that macro in the wrong place. Back then it was
called differently, it got later renamed but this is the original
commit that provided it.

> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> > ---
> > I have an upcoming driver that will use this but which can also be built
> > on non-DT systems. I'd like to get that in as a fix to avoid inter-tree
> > dependencies later.
>
> Do you have a link?
>

Sure, it's here: https://github.com/brgl/linux/tree/topic/gpio-virtual-consumer

> > --- a/include/linux/of.h
> > +++ b/include/linux/of.h
> > @@ -362,9 +362,6 @@ extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
> >                                                  int index);
> >  extern u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread);
> >
> > -#define for_each_property_of_node(dn, pp) \
> > -       for (pp = dn->properties; pp != NULL; pp = pp->next)
> > -
> >  extern int of_n_addr_cells(struct device_node *np);
> >  extern int of_n_size_cells(struct device_node *np);
> >  extern const struct of_device_id *of_match_node(
> > @@ -892,6 +889,9 @@ static inline int of_prop_val_eq(struct property *p1, struct property *p2)
> >                !memcmp(p1->value, p2->value, (size_t)p1->length);
> >  }
> >
> > +#define for_each_property_of_node(dn, pp) \
> > +       for (pp = dn->properties; pp != NULL; pp = pp->next)
>
> Is this safe if !OF? Can dn be NULL?
>

The way I use it[1], it's safe but it's a good point, I'll send a follow-up.

Thanks,
Bart

> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds

[1] https://github.com/brgl/linux/blob/topic/gpio-virtual-consumer/drivers/gpio/gpio-virtuser.c#L878

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Rob Herring]

On Tue, Mar 5, 2024 at 2:32 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Bartosz,
>
> On Sun, Mar 3, 2024 at 11:49 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> >
> > for_each_property_of_node() is a macro and so doesn't have a stub inline
> > function for !OF. Move it out of the relevant #ifdef to make it available
> > to all users.
>
> Thanks for your patch, which is now commit ad8ee969d7e34dd3 ("of: make
> for_each_property_of_node() available to to !OF") in dt-rh/for-next
>
> > Fixes: 611cad720148 ("dt: add of_alias_scan and of_alias_get_id")
>
> How is this related?
>
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> > ---
> > I have an upcoming driver that will use this but which can also be built
> > on non-DT systems. I'd like to get that in as a fix to avoid inter-tree
> > dependencies later.
>
> Do you have a link?
>
> > --- a/include/linux/of.h
> > +++ b/include/linux/of.h
> > @@ -362,9 +362,6 @@ extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
> >                                                  int index);
> >  extern u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread);
> >
> > -#define for_each_property_of_node(dn, pp) \
> > -       for (pp = dn->properties; pp != NULL; pp = pp->next)
> > -
> >  extern int of_n_addr_cells(struct device_node *np);
> >  extern int of_n_size_cells(struct device_node *np);
> >  extern const struct of_device_id *of_match_node(
> > @@ -892,6 +889,9 @@ static inline int of_prop_val_eq(struct property *p1, struct property *p2)
> >                !memcmp(p1->value, p2->value, (size_t)p1->length);
> >  }
> >
> > +#define for_each_property_of_node(dn, pp) \
> > +       for (pp = dn->properties; pp != NULL; pp = pp->next)
>
> Is this safe if !OF? Can dn be NULL?

Good point. I would say running code shouldn't reach this though.
Also, it should be written in a way it gets optimized away if !OF is
valid.

Long term, I want to make struct device_node opaque. So if we really
want to fix this, I think we'd want to convert this to use an iterator
function. Though I guess any user would be mucking with struct
property too, so the whole loop would need to be reworked. So in
conclusion, don't use for_each_property_of_node(). :) Shrug.

Rob

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Bartosz Golaszewski]

On Tue, 5 Mar 2024 18:56:04 +0100, Rob Herring <robh+dt@kernel.org> said:
>
> Long term, I want to make struct device_node opaque. So if we really
> want to fix this, I think we'd want to convert this to use an iterator
> function. Though I guess any user would be mucking with struct
> property too, so the whole loop would need to be reworked. So in
> conclusion, don't use for_each_property_of_node(). :) Shrug.
>

I basically just need to get the list of all properties of a node. Even just
names. I'm working on a testing driver that needs to request all GPIOs assigned
to it over DT so it must find all `foo-gpios` properties.

How about:

int of_node_for_each_property(struct device_node *dn, int
(*func)(struct property *, void *), void *data)

as the iterator? You didn't say if you want to make struct property opaque as
well but even then it can be used with provided interfaces.

Bart

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Rob Herring]

On Tue, Mar 5, 2024 at 12:46 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>
> On Tue, 5 Mar 2024 18:56:04 +0100, Rob Herring <robh+dt@kernel.org> said:
> >
> > Long term, I want to make struct device_node opaque. So if we really
> > want to fix this, I think we'd want to convert this to use an iterator
> > function. Though I guess any user would be mucking with struct
> > property too, so the whole loop would need to be reworked. So in
> > conclusion, don't use for_each_property_of_node(). :) Shrug.
> >
>
> I basically just need to get the list of all properties of a node. Even just
> names. I'm working on a testing driver that needs to request all GPIOs assigned
> to it over DT so it must find all `foo-gpios` properties.
>
> How about:
>
> int of_node_for_each_property(struct device_node *dn, int
> (*func)(struct property *, void *), void *data)
>
> as the iterator?

Why would we make the caller provide the iterator? We just need a
function call like the other iterators rather than directly
dereferencing the pointers: of_next_property_iter(node, last_prop)

> You didn't say if you want to make struct property opaque as
> well but even then it can be used with provided interfaces.

Yes, I'd like to make struct property opaque as well. That's probably
the first step.

Rob

Re: [PATCH] of: make for_each_property_of_node() available to to !OF

[Bartosz Golaszewski]

On Wed, Mar 6, 2024 at 8:34 PM Rob Herring <robh+dt@kernel.org> wrote:
>
> On Tue, Mar 5, 2024 at 12:46 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> >
> > On Tue, 5 Mar 2024 18:56:04 +0100, Rob Herring <robh+dt@kernel.org> said:
> > >
> > > Long term, I want to make struct device_node opaque. So if we really
> > > want to fix this, I think we'd want to convert this to use an iterator
> > > function. Though I guess any user would be mucking with struct
> > > property too, so the whole loop would need to be reworked. So in
> > > conclusion, don't use for_each_property_of_node(). :) Shrug.
> > >
> >
> > I basically just need to get the list of all properties of a node. Even just
> > names. I'm working on a testing driver that needs to request all GPIOs assigned
> > to it over DT so it must find all `foo-gpios` properties.
> >
> > How about:
> >
> > int of_node_for_each_property(struct device_node *dn, int
> > (*func)(struct property *, void *), void *data)
> >
> > as the iterator?
>
> Why would we make the caller provide the iterator? We just need a
> function call like the other iterators rather than directly
> dereferencing the pointers: of_next_property_iter(node, last_prop)
>
> > You didn't say if you want to make struct property opaque as
> > well but even then it can be used with provided interfaces.
>
> Yes, I'd like to make struct property opaque as well. That's probably
> the first step.
>
> Rob

Or maybe we should implement it at the fwnode_operations level?
Although not sure how to handle it as fwnode doesn't have a separate
structure for properties.

Bart