Introduce the scoped variant of the
fwnode_for_each_available_child_node() to automatically decrement the
child's refcount when it goes out of scope, removing the need for
explicit calls to fwnode_handle_put().
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
include/linux/property.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/include/linux/property.h b/include/linux/property.h
index 61fc20e5f81f..b37508ecf606 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -168,6 +168,11 @@ struct fwnode_handle *fwnode_get_next_available_child_node(
for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\
child = fwnode_get_next_available_child_node(fwnode, child))
+#define fwnode_for_each_available_child_node_scoped(fwnode, child) \
+ for (struct fwnode_handle *child __free(fwnode_handle) = \
+ fwnode_get_next_available_child_node(fwnode, NULL); child; \
+ child = fwnode_get_next_available_child_node(fwnode, child))
+
struct fwnode_handle *device_get_next_child_node(const struct device *dev,
struct fwnode_handle *child);
--
2.43.0Hi Javier,
On Tue, Oct 08, 2024 at 06:10:27PM +0200, Javier Carrasco wrote:
> Introduce the scoped variant of the
> fwnode_for_each_available_child_node() to automatically decrement the
> child's refcount when it goes out of scope, removing the need for
> explicit calls to fwnode_handle_put().
>
> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
> ---
> include/linux/property.h | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/include/linux/property.h b/include/linux/property.h
> index 61fc20e5f81f..b37508ecf606 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h
> @@ -168,6 +168,11 @@ struct fwnode_handle *fwnode_get_next_available_child_node(
> for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\
> child = fwnode_get_next_available_child_node(fwnode, child))
>
> +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \
> + for (struct fwnode_handle *child __free(fwnode_handle) = \
> + fwnode_get_next_available_child_node(fwnode, NULL); child; \
> + child = fwnode_get_next_available_child_node(fwnode, child))
> +
On OF, the implementation of the .get_next_child_node() fwnode op is:
static struct fwnode_handle *
of_fwnode_get_next_child_node(const struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
return of_fwnode_handle(of_get_next_available_child(to_of_node(fwnode),
to_of_node(child)));
}
On ACPI we currently have .device_is_available() returning false but that
probably should be returning true instead (it's been virtually unused
previously).
That makes fwnode_get_next_available_child_node() and
fwnode_get_next_child_node() equivalent on both ACPI and OF. Presumably
creating unavailable nodes would be useless on swnode, too.
So my question is: what do we gain by adding all these fwnode_*available()
helpers?
> struct fwnode_handle *device_get_next_child_node(const struct device *dev,
> struct fwnode_handle *child);
--
Regards,
Sakari Ailus
On 11/10/2024 07:39, Sakari Ailus wrote:
> Hi Javier,
>
> On Tue, Oct 08, 2024 at 06:10:27PM +0200, Javier Carrasco wrote:
>> Introduce the scoped variant of the
>> fwnode_for_each_available_child_node() to automatically decrement the
>> child's refcount when it goes out of scope, removing the need for
>> explicit calls to fwnode_handle_put().
>>
>> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
>> ---
>> include/linux/property.h | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/include/linux/property.h b/include/linux/property.h
>> index 61fc20e5f81f..b37508ecf606 100644
>> --- a/include/linux/property.h
>> +++ b/include/linux/property.h
>> @@ -168,6 +168,11 @@ struct fwnode_handle *fwnode_get_next_available_child_node(
>> for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\
>> child = fwnode_get_next_available_child_node(fwnode, child))
>>
>> +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \
>> + for (struct fwnode_handle *child __free(fwnode_handle) = \
>> + fwnode_get_next_available_child_node(fwnode, NULL); child; \
>> + child = fwnode_get_next_available_child_node(fwnode, child))
>> +
>
> On OF, the implementation of the .get_next_child_node() fwnode op is:
>
> static struct fwnode_handle *
> of_fwnode_get_next_child_node(const struct fwnode_handle *fwnode,
> struct fwnode_handle *child)
> {
> return of_fwnode_handle(of_get_next_available_child(to_of_node(fwnode),
> to_of_node(child)));
> }
>
> On ACPI we currently have .device_is_available() returning false but that
> probably should be returning true instead (it's been virtually unused
> previously).
>
> That makes fwnode_get_next_available_child_node() and
> fwnode_get_next_child_node() equivalent on both ACPI and OF. Presumably
> creating unavailable nodes would be useless on swnode, too.
>
> So my question is: what do we gain by adding all these fwnode_*available()
> helpers?
>
>> struct fwnode_handle *device_get_next_child_node(const struct device *dev,
>> struct fwnode_handle *child);
>
Hi Sakari, thanks for your feedback.
I thought that the difference is not in OF (which either way ends up
calling __of_device_is_available()), but in ACPI.
For fwnode_for_each_child_node(), the ACPI callback is
acpi_get_next_subnode(), and I don't see that the device_is_available()
callback is used in that case.
For fwnode_for_each_available_child_node(),
fwnode_get_next_available_child_node() is used, which checks
fwnode_device_is_available(), which then calls device_is_available().
What's the catch?
Thanks again and best regards,
Javier Carrasco
Hi Javier,
On Fri, Oct 11, 2024 at 10:34:32AM +0200, Javier Carrasco wrote:
> On 11/10/2024 07:39, Sakari Ailus wrote:
> > Hi Javier,
> >
> > On Tue, Oct 08, 2024 at 06:10:27PM +0200, Javier Carrasco wrote:
> >> Introduce the scoped variant of the
> >> fwnode_for_each_available_child_node() to automatically decrement the
> >> child's refcount when it goes out of scope, removing the need for
> >> explicit calls to fwnode_handle_put().
> >>
> >> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
> >> ---
> >> include/linux/property.h | 5 +++++
> >> 1 file changed, 5 insertions(+)
> >>
> >> diff --git a/include/linux/property.h b/include/linux/property.h
> >> index 61fc20e5f81f..b37508ecf606 100644
> >> --- a/include/linux/property.h
> >> +++ b/include/linux/property.h
> >> @@ -168,6 +168,11 @@ struct fwnode_handle *fwnode_get_next_available_child_node(
> >> for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\
> >> child = fwnode_get_next_available_child_node(fwnode, child))
> >>
> >> +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \
> >> + for (struct fwnode_handle *child __free(fwnode_handle) = \
> >> + fwnode_get_next_available_child_node(fwnode, NULL); child; \
> >> + child = fwnode_get_next_available_child_node(fwnode, child))
> >> +
> >
> > On OF, the implementation of the .get_next_child_node() fwnode op is:
> >
> > static struct fwnode_handle *
> > of_fwnode_get_next_child_node(const struct fwnode_handle *fwnode,
> > struct fwnode_handle *child)
> > {
> > return of_fwnode_handle(of_get_next_available_child(to_of_node(fwnode),
> > to_of_node(child)));
> > }
> >
> > On ACPI we currently have .device_is_available() returning false but that
> > probably should be returning true instead (it's been virtually unused
> > previously).
> >
> > That makes fwnode_get_next_available_child_node() and
> > fwnode_get_next_child_node() equivalent on both ACPI and OF. Presumably
> > creating unavailable nodes would be useless on swnode, too.
> >
> > So my question is: what do we gain by adding all these fwnode_*available()
> > helpers?
> >
> >> struct fwnode_handle *device_get_next_child_node(const struct device *dev,
> >> struct fwnode_handle *child);
> >
>
> Hi Sakari, thanks for your feedback.
>
> I thought that the difference is not in OF (which either way ends up
> calling __of_device_is_available()), but in ACPI.
>
> For fwnode_for_each_child_node(), the ACPI callback is
> acpi_get_next_subnode(), and I don't see that the device_is_available()
> callback is used in that case.
fwnode_get_next_available_child_node() also calls
fwnode_device_is_available() and that returns false on all non-device nodes
right now. As noted above, fwnode_device_is_available() should probably
return true for non-device nodes on ACPI. I'll post a patch.
>
> For fwnode_for_each_available_child_node(),
> fwnode_get_next_available_child_node() is used, which checks
> fwnode_device_is_available(), which then calls device_is_available().
>
> What's the catch?
--
Kind regards,
Sakari Ailus
On 11/10/2024 11:54, Sakari Ailus wrote:
> Hi Javier,
>
> On Fri, Oct 11, 2024 at 10:34:32AM +0200, Javier Carrasco wrote:
>> On 11/10/2024 07:39, Sakari Ailus wrote:
>>> Hi Javier,
>>>
>>> On Tue, Oct 08, 2024 at 06:10:27PM +0200, Javier Carrasco wrote:
>>>> Introduce the scoped variant of the
>>>> fwnode_for_each_available_child_node() to automatically decrement the
>>>> child's refcount when it goes out of scope, removing the need for
>>>> explicit calls to fwnode_handle_put().
>>>>
>>>> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
>>>> ---
>>>> include/linux/property.h | 5 +++++
>>>> 1 file changed, 5 insertions(+)
>>>>
>>>> diff --git a/include/linux/property.h b/include/linux/property.h
>>>> index 61fc20e5f81f..b37508ecf606 100644
>>>> --- a/include/linux/property.h
>>>> +++ b/include/linux/property.h
>>>> @@ -168,6 +168,11 @@ struct fwnode_handle *fwnode_get_next_available_child_node(
>>>> for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\
>>>> child = fwnode_get_next_available_child_node(fwnode, child))
>>>>
>>>> +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \
>>>> + for (struct fwnode_handle *child __free(fwnode_handle) = \
>>>> + fwnode_get_next_available_child_node(fwnode, NULL); child; \
>>>> + child = fwnode_get_next_available_child_node(fwnode, child))
>>>> +
>>>
>>> On OF, the implementation of the .get_next_child_node() fwnode op is:
>>>
>>> static struct fwnode_handle *
>>> of_fwnode_get_next_child_node(const struct fwnode_handle *fwnode,
>>> struct fwnode_handle *child)
>>> {
>>> return of_fwnode_handle(of_get_next_available_child(to_of_node(fwnode),
>>> to_of_node(child)));
>>> }
>>>
>>> On ACPI we currently have .device_is_available() returning false but that
>>> probably should be returning true instead (it's been virtually unused
>>> previously).
>>>
>>> That makes fwnode_get_next_available_child_node() and
>>> fwnode_get_next_child_node() equivalent on both ACPI and OF. Presumably
>>> creating unavailable nodes would be useless on swnode, too.
>>>
>>> So my question is: what do we gain by adding all these fwnode_*available()
>>> helpers?
>>>
>>>> struct fwnode_handle *device_get_next_child_node(const struct device *dev,
>>>> struct fwnode_handle *child);
>>>
>>
>> Hi Sakari, thanks for your feedback.
>>
>> I thought that the difference is not in OF (which either way ends up
>> calling __of_device_is_available()), but in ACPI.
>>
>> For fwnode_for_each_child_node(), the ACPI callback is
>> acpi_get_next_subnode(), and I don't see that the device_is_available()
>> callback is used in that case.
>
> fwnode_get_next_available_child_node() also calls
> fwnode_device_is_available() and that returns false on all non-device nodes
> right now. As noted above, fwnode_device_is_available() should probably
> return true for non-device nodes on ACPI. I'll post a patch.
>
fwnode_device_is_available() is indeed called in
fwnode_get_next_available_child_node(), as I stated a couple of lines below.
My question on the other hand was how that is called in
fwnode_for_each_child_node(), as I could not see any call to check
availability in acpi_get_next_subnode().
That is what confused me about the _available_ macros being the same as
their counterparts without the _available_.
Could you please clarify that? Thanks again.
>>
>> For fwnode_for_each_available_child_node(),
>> fwnode_get_next_available_child_node() is used, which checks
>> fwnode_device_is_available(), which then calls device_is_available().
>>
>> What's the catch?
>
On Tue, Oct 08, 2024 at 06:10:27PM +0200, Javier Carrasco wrote: > Introduce the scoped variant of the > fwnode_for_each_available_child_node() to automatically decrement the > child's refcount when it goes out of scope, removing the need for > explicit calls to fwnode_handle_put(). ... > +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \ > + for (struct fwnode_handle *child __free(fwnode_handle) = \ > + fwnode_get_next_available_child_node(fwnode, NULL); child; \ > + child = fwnode_get_next_available_child_node(fwnode, child)) I like the wrapping you have done here. Can you align the device_for_each_child_node_scoped() to follow your variant? (probably in an additional patch) For this one Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> -- With Best Regards, Andy Shevchenko
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