[PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
proper platform driver") qe_add_gpiochips() was walking the device
tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".

After that commit the discovery is handled by the platform core,
therefore it is necessary to call of_platform_default_populate() on
the par_io node.

Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
---
 drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
index a5e2d0e5ab51..02ca556c8db0 100644
--- a/drivers/soc/fsl/qe/qe_io.c
+++ b/drivers/soc/fsl/qe/qe_io.c
@@ -15,6 +15,7 @@
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/ioport.h>
+#include <linux/of_platform.h>
 
 #include <asm/io.h>
 #include <soc/fsl/qe/qe.h>
@@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
 	return 0;
 }
 EXPORT_SYMBOL(par_io_of_config);
+
+static int __init par_io_populate(void)
+{
+	struct device_node *np = of_find_node_by_name(NULL, "par_io");
+
+	if (!np)
+		return 0;
+
+	of_platform_default_populate(np, NULL, NULL);
+	of_node_put(np);
+
+	return 0;
+}
+arch_initcall(par_io_populate);
-- 
2.54.0

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Bartosz Golaszewski]

On Wed, 29 Jul 2026 16:10:36 +0200, "Christophe Leroy (CS GROUP)"
<chleroy@kernel.org> said:
> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
> proper platform driver") qe_add_gpiochips() was walking the device
> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>
> After that commit the discovery is handled by the platform core,
> therefore it is necessary to call of_platform_default_populate() on
> the par_io node.
>
> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
> ---

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Herve Codina]

Hi Christophe,

On Wed, 29 Jul 2026 16:10:36 +0200
"Christophe Leroy (CS GROUP)" <chleroy@kernel.org> wrote:

> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
> proper platform driver") qe_add_gpiochips() was walking the device
> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
> 
> After that commit the discovery is handled by the platform core,
> therefore it is necessary to call of_platform_default_populate() on
> the par_io node.
> 
> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
> ---
>  drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
> index a5e2d0e5ab51..02ca556c8db0 100644
> --- a/drivers/soc/fsl/qe/qe_io.c
> +++ b/drivers/soc/fsl/qe/qe_io.c
> @@ -15,6 +15,7 @@
>  #include <linux/errno.h>
>  #include <linux/module.h>
>  #include <linux/ioport.h>
> +#include <linux/of_platform.h>
>  
>  #include <asm/io.h>
>  #include <soc/fsl/qe/qe.h>
> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
>  	return 0;
>  }
>  EXPORT_SYMBOL(par_io_of_config);
> +
> +static int __init par_io_populate(void)
> +{
> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");
> +
> +	if (!np)
> +		return 0;
> +
> +	of_platform_default_populate(np, NULL, NULL);
> +	of_node_put(np);
> +
> +	return 0;
> +}
> +arch_initcall(par_io_populate);


The par_io node is a sub-node of the soc@xxx node.
The soc@xxx node is simple-bus compatible. This child node should be
populated.

Why do we need this additional of_platform_default_populate?

Also par_io node has a compatible. Maybe the related driver should call
of_platform_populate() to populate children of par_io if needed. If this
driver is missing, maybe it should be created.

Do I miss something?

Best regards,
Hervé

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

Hi Hervé,

Le 29/07/2026 à 17:21, Herve Codina a écrit :
> Hi Christophe,
> 
> On Wed, 29 Jul 2026 16:10:36 +0200
> "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> wrote:
> 
>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>> proper platform driver") qe_add_gpiochips() was walking the device
>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>
>> After that commit the discovery is handled by the platform core,
>> therefore it is necessary to call of_platform_default_populate() on
>> the par_io node.
>>
>> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
>> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
>> ---
>>   drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
>>
>> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
>> index a5e2d0e5ab51..02ca556c8db0 100644
>> --- a/drivers/soc/fsl/qe/qe_io.c
>> +++ b/drivers/soc/fsl/qe/qe_io.c
>> @@ -15,6 +15,7 @@
>>   #include <linux/errno.h>
>>   #include <linux/module.h>
>>   #include <linux/ioport.h>
>> +#include <linux/of_platform.h>
>>   
>>   #include <asm/io.h>
>>   #include <soc/fsl/qe/qe.h>
>> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
>>   	return 0;
>>   }
>>   EXPORT_SYMBOL(par_io_of_config);
>> +
>> +static int __init par_io_populate(void)
>> +{
>> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");
>> +
>> +	if (!np)
>> +		return 0;
>> +
>> +	of_platform_default_populate(np, NULL, NULL);
>> +	of_node_put(np);
>> +
>> +	return 0;
>> +}
>> +arch_initcall(par_io_populate);
> 
> 
> The par_io node is a sub-node of the soc@xxx node.
> The soc@xxx node is simple-bus compatible. This child node should be
> populated.
> 
> Why do we need this additional of_platform_default_populate?
> 
> Also par_io node has a compatible. Maybe the related driver should call
> of_platform_populate() to populate children of par_io if needed. If this
> driver is missing, maybe it should be created.
> 
> Do I miss something?

As discussed together off-line, at the time being the par_io driver is 
not a platform driver. par_io_init() is called from setup_arch() by some 
board setups.

In order to fix the regression, I keep it minimal with an 
arch_initcall() function which is equivalent to what we had before 
changing this driver to a platform driver. It will also ease applying 
the fix to stable without too much churn.

It will still be possible to rework par_io driver in a follow-up patch 
and change it to a propoer platform driver.

Christophe

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

On Wed, 29 Jul 2026 16:10:36 +0200, Christophe Leroy (CS GROUP) wrote:
> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
> proper platform driver") qe_add_gpiochips() was walking the device
> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
> 
> After that commit the discovery is handled by the platform core,
> therefore it is necessary to call of_platform_default_populate() on
> the par_io node.
> 
> [...]

Applied, thanks!

[1/1] soc: fsl: qe: properly scan GPIO nodes at startup
      commit: cf91e5909e620b77164b53c9b316a5c1f11f9ea7

Best regards,
-- 
Christophe Leroy (CS GROUP) <chleroy@kernel.org>

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Herve Codina]

Hi Christophe,

On Thu, 30 Jul 2026 10:11:29 +0200
"Christophe Leroy (CS GROUP)" <chleroy@kernel.org> wrote:

> Hi Hervé,
> 
> Le 29/07/2026 à 17:21, Herve Codina a écrit :
> > Hi Christophe,
> > 
> > On Wed, 29 Jul 2026 16:10:36 +0200
> > "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> wrote:
> >   
> >> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
> >> proper platform driver") qe_add_gpiochips() was walking the device
> >> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
> >>
> >> After that commit the discovery is handled by the platform core,
> >> therefore it is necessary to call of_platform_default_populate() on
> >> the par_io node.
> >>
> >> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
> >> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
> >> ---
> >>   drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
> >>   1 file changed, 15 insertions(+)
> >>
> >> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
> >> index a5e2d0e5ab51..02ca556c8db0 100644
> >> --- a/drivers/soc/fsl/qe/qe_io.c
> >> +++ b/drivers/soc/fsl/qe/qe_io.c
> >> @@ -15,6 +15,7 @@
> >>   #include <linux/errno.h>
> >>   #include <linux/module.h>
> >>   #include <linux/ioport.h>
> >> +#include <linux/of_platform.h>
> >>   
> >>   #include <asm/io.h>
> >>   #include <soc/fsl/qe/qe.h>
> >> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
> >>   	return 0;
> >>   }
> >>   EXPORT_SYMBOL(par_io_of_config);
> >> +
> >> +static int __init par_io_populate(void)
> >> +{
> >> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");
> >> +
> >> +	if (!np)
> >> +		return 0;
> >> +
> >> +	of_platform_default_populate(np, NULL, NULL);
> >> +	of_node_put(np);
> >> +
> >> +	return 0;
> >> +}
> >> +arch_initcall(par_io_populate);  
> > 
> > 
> > The par_io node is a sub-node of the soc@xxx node.
> > The soc@xxx node is simple-bus compatible. This child node should be
> > populated.
> > 
> > Why do we need this additional of_platform_default_populate?
> > 
> > Also par_io node has a compatible. Maybe the related driver should call
> > of_platform_populate() to populate children of par_io if needed. If this
> > driver is missing, maybe it should be created.
> > 
> > Do I miss something?  
> 
> As discussed together off-line, at the time being the par_io driver is 
> not a platform driver. par_io_init() is called from setup_arch() by some 
> board setups.
> 
> In order to fix the regression, I keep it minimal with an 
> arch_initcall() function which is equivalent to what we had before 
> changing this driver to a platform driver. It will also ease applying 
> the fix to stable without too much churn.
> 
> It will still be possible to rework par_io driver in a follow-up patch 
> and change it to a propoer platform driver.
> 

Yes, indeed, this makes sense.

Thanks for the clarification.

Best regards,
Hervé

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Krzysztof Kozlowski]

On 29/07/2026 16:10, Christophe Leroy (CS GROUP) wrote:
> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
> proper platform driver") qe_add_gpiochips() was walking the device
> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
> 
> After that commit the discovery is handled by the platform core,
> therefore it is necessary to call of_platform_default_populate() on
> the par_io node.
> 
> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
> ---
>  drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
> index a5e2d0e5ab51..02ca556c8db0 100644
> --- a/drivers/soc/fsl/qe/qe_io.c
> +++ b/drivers/soc/fsl/qe/qe_io.c
> @@ -15,6 +15,7 @@
>  #include <linux/errno.h>
>  #include <linux/module.h>
>  #include <linux/ioport.h>
> +#include <linux/of_platform.h>
>  
>  #include <asm/io.h>
>  #include <soc/fsl/qe/qe.h>
> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
>  	return 0;
>  }
>  EXPORT_SYMBOL(par_io_of_config);
> +
> +static int __init par_io_populate(void)
> +{
> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");

No, node name must not be ABI. Especially wrong node name.

Best regards,
Krzysztof

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Krzysztof Kozlowski]

On 30/07/2026 10:14, Christophe Leroy (CS GROUP) wrote:
> 
> On Wed, 29 Jul 2026 16:10:36 +0200, Christophe Leroy (CS GROUP) wrote:
>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>> proper platform driver") qe_add_gpiochips() was walking the device
>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>
>> After that commit the discovery is handled by the platform core,
>> therefore it is necessary to call of_platform_default_populate() on
>> the par_io node.
>>
>> [...]
> 
> Applied, thanks!
> 
> [1/1] soc: fsl: qe: properly scan GPIO nodes at startup
>       commit: cf91e5909e620b77164b53c9b316a5c1f11f9ea7

You left very little time to respond to this - one day - and introduced
undocumented disallowed ABI. Please drop the patch. I will be objecting
to the entire pull request.

Best regards,
Krzysztof

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

Le 30/07/2026 à 13:14, Krzysztof Kozlowski a écrit :
> On 29/07/2026 16:10, Christophe Leroy (CS GROUP) wrote:
>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>> proper platform driver") qe_add_gpiochips() was walking the device
>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>
>> After that commit the discovery is handled by the platform core,
>> therefore it is necessary to call of_platform_default_populate() on
>> the par_io node.
>>
>> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
>> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
>> ---
>>   drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
>>
>> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
>> index a5e2d0e5ab51..02ca556c8db0 100644
>> --- a/drivers/soc/fsl/qe/qe_io.c
>> +++ b/drivers/soc/fsl/qe/qe_io.c
>> @@ -15,6 +15,7 @@
>>   #include <linux/errno.h>
>>   #include <linux/module.h>
>>   #include <linux/ioport.h>
>> +#include <linux/of_platform.h>
>>   
>>   #include <asm/io.h>
>>   #include <soc/fsl/qe/qe.h>
>> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
>>   	return 0;
>>   }
>>   EXPORT_SYMBOL(par_io_of_config);
>> +
>> +static int __init par_io_populate(void)
>> +{
>> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");
> 
> No, node name must not be ABI. Especially wrong node name.

What's wrong with the node name ?

Regardless, I messed it up, I wanted to use type but copy/pasted 
of_find_node_by_name(NULL, "par_io") from quirk_mpc8360e_qe_enet10() in 
arch/powerpc/platforms/83xx/km83xx.c instead.

Is it OK to use of_find_node_by_type(NULL, "par_io") instead ?

We have:

$ git grep par_io arch/powerpc/boot/dts/
arch/powerpc/boot/dts/fsl/mpc8568mds.dts:               par_io@e0100 {
arch/powerpc/boot/dts/fsl/mpc8568si-post.dtsi:  par_io@e0100 {
arch/powerpc/boot/dts/fsl/mpc8568si-post.dtsi:          device_type = 
"par_io";
arch/powerpc/boot/dts/fsl/mpc8569mds.dts:               par_io@e0100 {
arch/powerpc/boot/dts/fsl/mpc8569si-post.dtsi:  par_io@e0100 {
arch/powerpc/boot/dts/fsl/mpc8569si-post.dtsi:          device_type = 
"par_io";
arch/powerpc/boot/dts/fsl/p1021mds.dts:         par_io@e0100 {
arch/powerpc/boot/dts/fsl/p1021mds.dts:                 device_type = 
"par_io";
arch/powerpc/boot/dts/fsl/p1025rdb.dtsi:        par_io@e0100 {
arch/powerpc/boot/dts/fsl/p1025rdb.dtsi:                device_type = 
"par_io";
arch/powerpc/boot/dts/fsl/p1025twr.dtsi:        par_io@e0100 {
arch/powerpc/boot/dts/fsl/p1025twr.dtsi:                device_type = 
"par_io";
arch/powerpc/boot/dts/kmeter1.dts:              par_io@1400 {
arch/powerpc/boot/dts/kmeter1.dts:                      compatible = 
"fsl,mpc8360-par_io";
arch/powerpc/boot/dts/mpc832x_rdb.dts:          par_io@1400 {
arch/powerpc/boot/dts/mpc832x_rdb.dts:                  device_type = 
"par_io";

Thanks
Christophe

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

Hi Krzysztof,

Le 30/07/2026 à 13:15, Krzysztof Kozlowski a écrit :
> On 30/07/2026 10:14, Christophe Leroy (CS GROUP) wrote:
>>
>> On Wed, 29 Jul 2026 16:10:36 +0200, Christophe Leroy (CS GROUP) wrote:
>>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>>> proper platform driver") qe_add_gpiochips() was walking the device
>>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>>
>>> After that commit the discovery is handled by the platform core,
>>> therefore it is necessary to call of_platform_default_populate() on
>>> the par_io node.
>>>
>>> [...]
>>
>> Applied, thanks!
>>
>> [1/1] soc: fsl: qe: properly scan GPIO nodes at startup
>>        commit: cf91e5909e620b77164b53c9b316a5c1f11f9ea7
> 
> You left very little time to respond to this - one day - and introduced
> undocumented disallowed ABI. Please drop the patch. I will be objecting
> to the entire pull request.

Yes sorry for that, I thought the reviewed-by: GPIO maintainer + 
discussion with Herve was enough.

I'll fix it up before sending pull request. Thanks for reviewing and 
providing feedback.

Christophe

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Krzysztof Kozlowski]

On 30/07/2026 14:01, Christophe Leroy (CS GROUP) wrote:
> 
> 
> Le 30/07/2026 à 13:14, Krzysztof Kozlowski a écrit :
>> On 29/07/2026 16:10, Christophe Leroy (CS GROUP) wrote:
>>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>>> proper platform driver") qe_add_gpiochips() was walking the device
>>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>>
>>> After that commit the discovery is handled by the platform core,
>>> therefore it is necessary to call of_platform_default_populate() on
>>> the par_io node.
>>>
>>> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
>>> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
>>> ---
>>>   drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
>>>   1 file changed, 15 insertions(+)
>>>
>>> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
>>> index a5e2d0e5ab51..02ca556c8db0 100644
>>> --- a/drivers/soc/fsl/qe/qe_io.c
>>> +++ b/drivers/soc/fsl/qe/qe_io.c
>>> @@ -15,6 +15,7 @@
>>>   #include <linux/errno.h>
>>>   #include <linux/module.h>
>>>   #include <linux/ioport.h>
>>> +#include <linux/of_platform.h>
>>>   
>>>   #include <asm/io.h>
>>>   #include <soc/fsl/qe/qe.h>
>>> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
>>>   	return 0;
>>>   }
>>>   EXPORT_SYMBOL(par_io_of_config);
>>> +
>>> +static int __init par_io_populate(void)
>>> +{
>>> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");
>>
>> No, node name must not be ABI. Especially wrong node name.
> 
> What's wrong with the node name ?

1. It causes W=2 warnings (which we might move to W=1 at some point)
2. It is not generic and DT spec asks for generic node names, although
maybe this part of code follows more of ePAPR than DT. But ePAPR v1.1
also was asking for generic node names.

> 
> Regardless, I messed it up, I wanted to use type but copy/pasted 
> of_find_node_by_name(NULL, "par_io") from quirk_mpc8360e_qe_enet10() in 
> arch/powerpc/platforms/83xx/km83xx.c instead.
> 
> Is it OK to use of_find_node_by_type(NULL, "par_io") instead ?

Well, depends. Is it a documented ABI?

> 
> We have:
> 
> $ git grep par_io arch/powerpc/boot/dts/
> arch/powerpc/boot/dts/fsl/mpc8568mds.dts:               par_io@e0100 {
> arch/powerpc/boot/dts/fsl/mpc8568si-post.dtsi:  par_io@e0100 {
> arch/powerpc/boot/dts/fsl/mpc8568si-post.dtsi:          device_type = 
> "par_io";

These are all DTS, does not matter really. ABI is not documented via DTS
but bindings.

Best regards,
Krzysztof

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Bartosz Golaszewski]

On Thu, 30 Jul 2026 13:15:25 +0200, Krzysztof Kozlowski <krzk@kernel.org> said:
> On 30/07/2026 10:14, Christophe Leroy (CS GROUP) wrote:
>>
>> On Wed, 29 Jul 2026 16:10:36 +0200, Christophe Leroy (CS GROUP) wrote:
>>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>>> proper platform driver") qe_add_gpiochips() was walking the device
>>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>>
>>> After that commit the discovery is handled by the platform core,
>>> therefore it is necessary to call of_platform_default_populate() on
>>> the par_io node.
>>>
>>> [...]
>>
>> Applied, thanks!
>>
>> [1/1] soc: fsl: qe: properly scan GPIO nodes at startup
>>       commit: cf91e5909e620b77164b53c9b316a5c1f11f9ea7
>
> You left very little time to respond to this - one day - and introduced
> undocumented disallowed ABI. Please drop the patch. I will be objecting
> to the entire pull request.
>

Hi,

Krzysztof explained to me what to watch out for in such patches. In this case
it's about an undocumented node name which now becomes ABI. I'm of course
retracting my R-b.

Thanks,
Bartosz

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

Le 30/07/2026 à 14:05, Krzysztof Kozlowski a écrit :
> On 30/07/2026 14:01, Christophe Leroy (CS GROUP) wrote:
>>
>>
>> Le 30/07/2026 à 13:14, Krzysztof Kozlowski a écrit :
>>> On 29/07/2026 16:10, Christophe Leroy (CS GROUP) wrote:
>>>> Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
>>>> proper platform driver") qe_add_gpiochips() was walking the device
>>>> tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".
>>>>
>>>> After that commit the discovery is handled by the platform core,
>>>> therefore it is necessary to call of_platform_default_populate() on
>>>> the par_io node.
>>>>
>>>> Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
>>>> Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
>>>> ---
>>>>    drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
>>>>    1 file changed, 15 insertions(+)
>>>>
>>>> diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
>>>> index a5e2d0e5ab51..02ca556c8db0 100644
>>>> --- a/drivers/soc/fsl/qe/qe_io.c
>>>> +++ b/drivers/soc/fsl/qe/qe_io.c
>>>> @@ -15,6 +15,7 @@
>>>>    #include <linux/errno.h>
>>>>    #include <linux/module.h>
>>>>    #include <linux/ioport.h>
>>>> +#include <linux/of_platform.h>
>>>>    
>>>>    #include <asm/io.h>
>>>>    #include <soc/fsl/qe/qe.h>
>>>> @@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
>>>>    	return 0;
>>>>    }
>>>>    EXPORT_SYMBOL(par_io_of_config);
>>>> +
>>>> +static int __init par_io_populate(void)
>>>> +{
>>>> +	struct device_node *np = of_find_node_by_name(NULL, "par_io");
>>>
>>> No, node name must not be ABI. Especially wrong node name.
>>
>> What's wrong with the node name ?
> 
> 1. It causes W=2 warnings (which we might move to W=1 at some point)
> 2. It is not generic and DT spec asks for generic node names, although
> maybe this part of code follows more of ePAPR than DT. But ePAPR v1.1
> also was asking for generic node names.
> 
>>
>> Regardless, I messed it up, I wanted to use type but copy/pasted
>> of_find_node_by_name(NULL, "par_io") from quirk_mpc8360e_qe_enet10() in
>> arch/powerpc/platforms/83xx/km83xx.c instead.
>>
>> Is it OK to use of_find_node_by_type(NULL, "par_io") instead ?
> 
> Well, depends. Is it a documented ABI?

In Documentation/devicetree/bindings/soc/fsl/cpm_qe/qe/par_io.txt:

Required properties:
- device_type : should be "par_io".
- reg : offset to the register set and its length.
- num-ports : number of Parallel I/O ports

Example:
par_io@1400 {
	reg = <1400 100>;
	#address-cells = <1>;
	#size-cells = <0>;
	device_type = "par_io";
	num-ports = <7>;
	ucc_pin@1 {
		......
	};

Is it OK ?

Thanks,
Christophe

Re: [PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Krzysztof Kozlowski]

On 30/07/2026 14:14, Christophe Leroy (CS GROUP) wrote:
>> Well, depends. Is it a documented ABI?
> 
> In Documentation/devicetree/bindings/soc/fsl/cpm_qe/qe/par_io.txt:
> 
> Required properties:
> - device_type : should be "par_io".
> - reg : offset to the register set and its length.
> - num-ports : number of Parallel I/O ports
> 
> Example:
> par_io@1400 {
> 	reg = <1400 100>;
> 	#address-cells = <1>;
> 	#size-cells = <0>;
> 	device_type = "par_io";
> 	num-ports = <7>;
> 	ucc_pin@1 {
> 		......
> 	};
> 
> Is it OK ?

Yes, this is fine.

Best regards,
Krzysztof

[PATCH] soc: fsl: qe: properly scan GPIO nodes at startup

[Christophe Leroy (CS GROUP)]

Before commit 156460811def ("soc: fsl: qe: Change GPIO driver to a
proper platform driver") qe_add_gpiochips() was walking the device
tree to find all nodes with compatible "fsl,mpc8323-qe-pario-bank".

After that commit the discovery is handled by the platform core,
therefore it is necessary to call of_platform_default_populate() on
the par_io node.

Fixes: 156460811def ("soc: fsl: qe: Change GPIO driver to a proper platform driver")
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
---
 drivers/soc/fsl/qe/qe_io.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/soc/fsl/qe/qe_io.c b/drivers/soc/fsl/qe/qe_io.c
index a5e2d0e5ab51..02ca556c8db0 100644
--- a/drivers/soc/fsl/qe/qe_io.c
+++ b/drivers/soc/fsl/qe/qe_io.c
@@ -15,6 +15,7 @@
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/ioport.h>
+#include <linux/of_platform.h>
 
 #include <asm/io.h>
 #include <soc/fsl/qe/qe.h>
@@ -184,3 +185,17 @@ int par_io_of_config(struct device_node *np)
 	return 0;
 }
 EXPORT_SYMBOL(par_io_of_config);
+
+static int __init par_io_populate(void)
+{
+	struct device_node *np = of_find_node_by_name(NULL, "par_io");
+
+	if (!np)
+		return 0;
+
+	of_platform_default_populate(np, NULL, NULL);
+	of_node_put(np);
+
+	return 0;
+}
+arch_initcall(par_io_populate);
-- 
2.54.0