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[PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers

Bartosz Golaszewski posted 12 patches 2 months, 4 weeks ago
There is a newer version of this series
[PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Posted by Bartosz Golaszewski 2 months, 4 weeks ago 
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Use the existing infrastructure for storing and looking up pin functions
in pinctrl core. Remove hand-crafted callbacks.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/pinctrl/qcom/pinctrl-msm.c | 43 ++++++++++++--------------------------
 1 file changed, 13 insertions(+), 30 deletions(-)

diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index f713c80d7f3eda06de027cd539e8decd4412876a..965f0cceac56697bc4cdb851c8201db7508c042e 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -31,6 +31,7 @@
 #include "../core.h"
 #include "../pinconf.h"
 #include "../pinctrl-utils.h"
+#include "../pinmux.h"
 
 #include "pinctrl-msm.h"
 
@@ -150,33 +151,6 @@ static int msm_pinmux_request(struct pinctrl_dev *pctldev, unsigned offset)
 	return gpiochip_line_is_valid(chip, offset) ? 0 : -EINVAL;
 }
 
-static int msm_get_functions_count(struct pinctrl_dev *pctldev)
-{
-	struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
-
-	return pctrl->soc->nfunctions;
-}
-
-static const char *msm_get_function_name(struct pinctrl_dev *pctldev,
-					 unsigned function)
-{
-	struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
-
-	return pctrl->soc->functions[function].name;
-}
-
-static int msm_get_function_groups(struct pinctrl_dev *pctldev,
-				   unsigned function,
-				   const char * const **groups,
-				   unsigned * const num_groups)
-{
-	struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
-
-	*groups = pctrl->soc->functions[function].groups;
-	*num_groups = pctrl->soc->functions[function].ngroups;
-	return 0;
-}
-
 static int msm_pinmux_set_mux(struct pinctrl_dev *pctldev,
 			      unsigned function,
 			      unsigned group)
@@ -288,9 +262,9 @@ static int msm_pinmux_request_gpio(struct pinctrl_dev *pctldev,
 
 static const struct pinmux_ops msm_pinmux_ops = {
 	.request		= msm_pinmux_request,
-	.get_functions_count	= msm_get_functions_count,
-	.get_function_name	= msm_get_function_name,
-	.get_function_groups	= msm_get_function_groups,
+	.get_functions_count	= pinmux_generic_get_function_count,
+	.get_function_name	= pinmux_generic_get_function_name,
+	.get_function_groups	= pinmux_generic_get_function_groups,
 	.gpio_request_enable	= msm_pinmux_request_gpio,
 	.set_mux		= msm_pinmux_set_mux,
 };
@@ -1552,6 +1526,7 @@ EXPORT_SYMBOL(msm_pinctrl_dev_pm_ops);
 int msm_pinctrl_probe(struct platform_device *pdev,
 		      const struct msm_pinctrl_soc_data *soc_data)
 {
+	const struct pinfunction *func;
 	struct msm_pinctrl *pctrl;
 	struct resource *res;
 	int ret;
@@ -1606,6 +1581,14 @@ int msm_pinctrl_probe(struct platform_device *pdev,
 		return PTR_ERR(pctrl->pctrl);
 	}
 
+	for (i = 0; i < soc_data->nfunctions; i++) {
+		func = &soc_data->functions[i];
+
+		ret = pinmux_generic_add_pinfunction(pctrl->pctrl, func, NULL);
+		if (ret < 0)
+			return ret;
+	}
+
 	ret = msm_gpio_init(pctrl);
 	if (ret)
 		return ret;

-- 
2.48.1
Re: [PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Posted by Linus Walleij 2 months, 3 weeks ago 
On Wed, Jul 9, 2025 at 4:39 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:

> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> Use the existing infrastructure for storing and looking up pin functions
> in pinctrl core. Remove hand-crafted callbacks.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Needless to say I'm a big fan of this patch set and it seems only
this patch 8/12 has outstanding comments.

Do you think you can do a quick iteration of it or does it require
a lot of time?

I am tempted to simply apply patches 1-7 to make your life
easier past v6.17, should I do this?

Yours,
Linus Walleij
Re: [PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Posted by Bartosz Golaszewski 2 months, 3 weeks ago 
On Fri, Jul 11, 2025 at 8:37 PM Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Wed, Jul 9, 2025 at 4:39 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>
> > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> >
> > Use the existing infrastructure for storing and looking up pin functions
> > in pinctrl core. Remove hand-crafted callbacks.
> >
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> Needless to say I'm a big fan of this patch set and it seems only
> this patch 8/12 has outstanding comments.
>
> Do you think you can do a quick iteration of it or does it require
> a lot of time?
>

I don't want to rush it. Let's make it v6.18 material as I want the
changes to spend some more time in next and not break anything. It
affects literally all qualcomm platforms after all.

> I am tempted to simply apply patches 1-7 to make your life
> easier past v6.17, should I do this?
>

Yes, please, they carry no functional change, it will be less baggage
for the future.

Bart
Re: [PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Posted by Konrad Dybcio 2 months, 4 weeks ago 
On 7/9/25 4:39 PM, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> Use the existing infrastructure for storing and looking up pin functions
> in pinctrl core. Remove hand-crafted callbacks.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> ---

[...]

>  int msm_pinctrl_probe(struct platform_device *pdev,
>  		      const struct msm_pinctrl_soc_data *soc_data)
>  {
> +	const struct pinfunction *func;
>  	struct msm_pinctrl *pctrl;
>  	struct resource *res;
>  	int ret;
> @@ -1606,6 +1581,14 @@ int msm_pinctrl_probe(struct platform_device *pdev,
>  		return PTR_ERR(pctrl->pctrl);
>  	}
>  
> +	for (i = 0; i < soc_data->nfunctions; i++) {
> +		func = &soc_data->functions[i];
> +
> +		ret = pinmux_generic_add_pinfunction(pctrl->pctrl, func, NULL);
> +		if (ret < 0)
> +			return ret;
> +	}

It's good in principle, but we're now going to house two copies of
the function data in memory... Can we trust __initconst nowadays?

Konrad
Re: [PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Posted by Bartosz Golaszewski 2 months, 4 weeks ago 
On Thu, Jul 10, 2025 at 2:25 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 7/9/25 4:39 PM, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> >
> > Use the existing infrastructure for storing and looking up pin functions
> > in pinctrl core. Remove hand-crafted callbacks.
> >
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> > ---
>
> [...]
>
> >  int msm_pinctrl_probe(struct platform_device *pdev,
> >                     const struct msm_pinctrl_soc_data *soc_data)
> >  {
> > +     const struct pinfunction *func;
> >       struct msm_pinctrl *pctrl;
> >       struct resource *res;
> >       int ret;
> > @@ -1606,6 +1581,14 @@ int msm_pinctrl_probe(struct platform_device *pdev,
> >               return PTR_ERR(pctrl->pctrl);
> >       }
> >
> > +     for (i = 0; i < soc_data->nfunctions; i++) {
> > +             func = &soc_data->functions[i];
> > +
> > +             ret = pinmux_generic_add_pinfunction(pctrl->pctrl, func, NULL);
> > +             if (ret < 0)
> > +                     return ret;
> > +     }
>
> It's good in principle, but we're now going to house two copies of
> the function data in memory... Can we trust __initconst nowadays?
>

Well, if I annotate the functions struct with __initconst, then it
does indeed end up in the .init.rodata section if that's your
question. Then the kernel seems to be freeing this in
./kernel/module/main.c so I sure hope we can trust it.

Do I understand correctly that you're implicitly asking to also
annotate all affected _functions structures across all tlmm drivers?

Alternatively: we can provide another interface:
pinmux_generic_add_const_pinfunction() which - instead of a deep-copy
- would simply store addresses of existing pinfunction structures in
the underlying radix tree.

Bartosz
Re: [PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Posted by Konrad Dybcio 2 months, 4 weeks ago 
On 7/10/25 3:38 PM, Bartosz Golaszewski wrote:
> On Thu, Jul 10, 2025 at 2:25 PM Konrad Dybcio
> <konrad.dybcio@oss.qualcomm.com> wrote:
>>
>> On 7/9/25 4:39 PM, Bartosz Golaszewski wrote:
>>> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>>>
>>> Use the existing infrastructure for storing and looking up pin functions
>>> in pinctrl core. Remove hand-crafted callbacks.
>>>
>>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>>> ---
>>
>> [...]
>>
>>>  int msm_pinctrl_probe(struct platform_device *pdev,
>>>                     const struct msm_pinctrl_soc_data *soc_data)
>>>  {
>>> +     const struct pinfunction *func;
>>>       struct msm_pinctrl *pctrl;
>>>       struct resource *res;
>>>       int ret;
>>> @@ -1606,6 +1581,14 @@ int msm_pinctrl_probe(struct platform_device *pdev,
>>>               return PTR_ERR(pctrl->pctrl);
>>>       }
>>>
>>> +     for (i = 0; i < soc_data->nfunctions; i++) {
>>> +             func = &soc_data->functions[i];
>>> +
>>> +             ret = pinmux_generic_add_pinfunction(pctrl->pctrl, func, NULL);
>>> +             if (ret < 0)
>>> +                     return ret;
>>> +     }
>>
>> It's good in principle, but we're now going to house two copies of
>> the function data in memory... Can we trust __initconst nowadays?
>>
> 
> Well, if I annotate the functions struct with __initconst, then it
> does indeed end up in the .init.rodata section if that's your
> question. Then the kernel seems to be freeing this in
> ./kernel/module/main.c so I sure hope we can trust it.
> 
> Do I understand correctly that you're implicitly asking to also
> annotate all affected _functions structures across all tlmm drivers?
> 
> Alternatively: we can provide another interface:
> pinmux_generic_add_const_pinfunction() which - instead of a deep-copy
> - would simply store addresses of existing pinfunction structures in
> the underlying radix tree.

This option seems like less of a churn

Konrad

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