[PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Robby Cai]

The FP9931 regulator requires a valid "vin" supply to operate correctly.
Therefore, the driver should treat "vin" as a mandatory supply.

This patchset updates the binding documentation to mark vin-supply as a
required property, and modifies the driver accordingly. As suggested in
the reviews from Andreas and Mark, v2 switches to using
devm_regulator_get() since the supply is mandatory.

Changes in v2:
  - Addressed feedback from Andreas and Mark by replacing
    devm_regulator_get_optional() with devm_regulator_get()
    because VIN is required.
  - Added a new patch updating the binding documentation to make
    vin-supply a required property.

v1: https://patchwork.kernel.org/project/imx/patch/20260312040148.GA4007088@shlinux88/

Robby Cai (2):
  dt-bindings: regulator: fitipower,fp9931: Make vin-supply property as
    required
  regulator: fp9931: Fix handling of mandatory "vin" supply

 .../devicetree/bindings/regulator/fitipower,fp9931.yaml         | 1 +
 drivers/regulator/fp9931.c                                      | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

-- 
2.37.1

[PATCH v2 1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required

[Robby Cai]

The FP9931 requires a vin power supply to operate, so mark vin-supply as
a required property in the binding.

Fixes: 80bbdefdfb417 ("dt-bindings: regulator: Add Fitipower FP9931/JD9930")
Signed-off-by: Robby Cai <robby.cai@nxp.com>
---
 .../devicetree/bindings/regulator/fitipower,fp9931.yaml          | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/regulator/fitipower,fp9931.yaml b/Documentation/devicetree/bindings/regulator/fitipower,fp9931.yaml
index c6585e3bacbec..00d66b9230475 100644
--- a/Documentation/devicetree/bindings/regulator/fitipower,fp9931.yaml
+++ b/Documentation/devicetree/bindings/regulator/fitipower,fp9931.yaml
@@ -66,6 +66,7 @@ properties:
 required:
   - compatible
   - reg
+  - vin-supply
   - pg-gpios
   - enable-gpios
 
-- 
2.37.1

Re: [PATCH v2 1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required

[Mark Brown]

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On Fri, Mar 13, 2026 at 09:31:01PM +0800, Robby Cai wrote:
> The FP9931 requires a vin power supply to operate, so mark vin-supply as
> a required property in the binding.

Please submit patches using subject lines reflecting the style for the
subsystem, this makes it easier for people to identify relevant patches.
Look at what existing commits in the area you're changing are doing and
make sure your subject lines visually resemble what they're doing.
There's no need to resubmit to fix this alone.

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Re: [PATCH v2 1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required

[Andreas Kemnade]

On Fri, 13 Mar 2026 13:33:36 +0000
Mark Brown <broonie@kernel.org> wrote:

> On Fri, Mar 13, 2026 at 09:31:01PM +0800, Robby Cai wrote:
> > The FP9931 requires a vin power supply to operate, so mark vin-supply as
> > a required property in the binding.  
> 
> Please submit patches using subject lines reflecting the style for the
> subsystem, this makes it easier for people to identify relevant patches.
> Look at what existing commits in the area you're changing are doing and
> make sure your subject lines visually resemble what they're doing.
> There's no need to resubmit to fix this alone.

in short words (but manually typed, so time-consuming):
s/dt-bindings: regulator:/regulator: dt-bindings:/

Since I once have misunderstood that text block myself:
- this sounds like you are talking about the subject line as a whole
  and not only the prefix.

- Looking at common practice:
   git log  --pretty=format:%s  -- Documentation/devicetree/bindings/regulator/ | sed 's/^\([^:]*\):\([^:]*\):.*/\1:\2/'  | grep binding | head -n 100 | sort | uniq -c
   shows (besides random other stuff) around 70% "regulator: dt-bindings" and 30% "dt-bindings: regulator"
   so chances are that people might see a bunch of "dt-bindings: regulator" (happened to me once)
   if they do not invest time in doing proper statistic, I hove once thought: my prefix is right,
   so lets try to adjust the wording.

- for an unbiased reader, reading
  Documentation/devicetree/bindings/submitting-patches.rst helps

Maybe that helps to reduce some unnecessary churn in the future

Regards,
Andreas

Re: [PATCH v2 1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required

[Mark Brown]

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On Fri, Mar 13, 2026 at 03:16:43PM +0100, Andreas Kemnade wrote:
> Mark Brown <broonie@kernel.org> wrote:

> > Please submit patches using subject lines reflecting the style for the
> > subsystem, this makes it easier for people to identify relevant patches.
> > Look at what existing commits in the area you're changing are doing and
> > make sure your subject lines visually resemble what they're doing.
> > There's no need to resubmit to fix this alone.

> Since I once have misunderstood that text block myself:
> - this sounds like you are talking about the subject line as a whole
>   and not only the prefix.

It *might* be the rest of the subject line as well, very much less often
but it does happen (excessively long lines for example).

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Re: [PATCH v2 1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required

[Conor Dooley]

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Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

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[PATCH v2 2/2] regulator: fp9931: Fix handling of mandatory "vin" supply

[Robby Cai]

The FP9931 requires a mandatory "vin" power supply to operate.
Replace devm_regulator_get_optional() with devm_regulator_get() to
enforce this mandatory dependency.

Fixes: 12d821bd13d42 ("regulator: Add FP9931/JD9930 driver")
Signed-off-by: Robby Cai <robby.cai@nxp.com>
---
 drivers/regulator/fp9931.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/fp9931.c b/drivers/regulator/fp9931.c
index 69b3c712e5d58..d4ba818ec2c15 100644
--- a/drivers/regulator/fp9931.c
+++ b/drivers/regulator/fp9931.c
@@ -444,7 +444,7 @@ static int fp9931_probe(struct i2c_client *client)
 		return dev_err_probe(&client->dev, PTR_ERR(data->regmap),
 				     "failed to allocate regmap!\n");
 
-	data->vin_reg = devm_regulator_get_optional(&client->dev, "vin");
+	data->vin_reg = devm_regulator_get(&client->dev, "vin");
 	if (IS_ERR(data->vin_reg))
 		return dev_err_probe(&client->dev, PTR_ERR(data->vin_reg),
 				     "failed to get vin regulator\n");
-- 
2.37.1

Re: [PATCH v2 2/2] regulator: fp9931: Fix handling of mandatory "vin" supply

[Conor Dooley]

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On Fri, Mar 13, 2026 at 09:31:02PM +0800, Robby Cai wrote:
> The FP9931 requires a mandatory "vin" power supply to operate.
> Replace devm_regulator_get_optional() with devm_regulator_get() to
> enforce this mandatory dependency.
> 
> Fixes: 12d821bd13d42 ("regulator: Add FP9931/JD9930 driver")
> Signed-off-by: Robby Cai <robby.cai@nxp.com>
> ---
>  drivers/regulator/fp9931.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/regulator/fp9931.c b/drivers/regulator/fp9931.c
> index 69b3c712e5d58..d4ba818ec2c15 100644
> --- a/drivers/regulator/fp9931.c
> +++ b/drivers/regulator/fp9931.c
> @@ -444,7 +444,7 @@ static int fp9931_probe(struct i2c_client *client)
>  		return dev_err_probe(&client->dev, PTR_ERR(data->regmap),
>  				     "failed to allocate regmap!\n");
>  
> -	data->vin_reg = devm_regulator_get_optional(&client->dev, "vin");
> +	data->vin_reg = devm_regulator_get(&client->dev, "vin");

And this isn't an ABI break because the regulator core will invent a
dummy regulator?

What's the functional difference here?

>  	if (IS_ERR(data->vin_reg))
>  		return dev_err_probe(&client->dev, PTR_ERR(data->vin_reg),
>  				     "failed to get vin regulator\n");
> -- 
> 2.37.1
> 

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Re: [PATCH v2 2/2] regulator: fp9931: Fix handling of mandatory "vin" supply

[Robby Cai]

On Fri, Mar 13, 2026 at 05:24:31PM +0000, Conor Dooley wrote:
> On Fri, Mar 13, 2026 at 09:31:02PM +0800, Robby Cai wrote:
> > The FP9931 requires a mandatory "vin" power supply to operate.
> > Replace devm_regulator_get_optional() with devm_regulator_get() to
> > enforce this mandatory dependency.
> > 
> > Fixes: 12d821bd13d42 ("regulator: Add FP9931/JD9930 driver")
> > Signed-off-by: Robby Cai <robby.cai@nxp.com>
> > ---
> >  drivers/regulator/fp9931.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/regulator/fp9931.c b/drivers/regulator/fp9931.c
> > index 69b3c712e5d58..d4ba818ec2c15 100644
> > --- a/drivers/regulator/fp9931.c
> > +++ b/drivers/regulator/fp9931.c
> > @@ -444,7 +444,7 @@ static int fp9931_probe(struct i2c_client *client)
> >  		return dev_err_probe(&client->dev, PTR_ERR(data->regmap),
> >  				     "failed to allocate regmap!\n");
> >  
> > -	data->vin_reg = devm_regulator_get_optional(&client->dev, "vin");
> > +	data->vin_reg = devm_regulator_get(&client->dev, "vin");
> 
> And this isn't an ABI break because the regulator core will invent a
> dummy regulator?
> 
> What's the functional difference here?
> 

Yes, this change does not introduce an ABI break.

If the DT already specifies the 'vin' supply, nothing changes.

If the DT omits 'vin', the previous driver treated that as "no regulator"
via devm_regulator_get_optional() [1]. After this change, the driver still
continues to probe; the regulator core reports that a dummy supply is
being used.

[1] The original handling of devm_regulator_get_optional() had a defect,
    which v1 attempted to fix. Switching to devm_regulator_get() reflects
    the actual hardware requirement.


Regards,
Robby

Re: [PATCH v2 2/2] regulator: fp9931: Fix handling of mandatory "vin" supply

[Andreas Kemnade]

On Fri, 13 Mar 2026 17:24:31 +0000
Conor Dooley <conor@kernel.org> wrote:

> On Fri, Mar 13, 2026 at 09:31:02PM +0800, Robby Cai wrote:
> > The FP9931 requires a mandatory "vin" power supply to operate.
> > Replace devm_regulator_get_optional() with devm_regulator_get() to
> > enforce this mandatory dependency.
> > 
> > Fixes: 12d821bd13d42 ("regulator: Add FP9931/JD9930 driver")
> > Signed-off-by: Robby Cai <robby.cai@nxp.com>
> > ---
> >  drivers/regulator/fp9931.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/regulator/fp9931.c b/drivers/regulator/fp9931.c
> > index 69b3c712e5d58..d4ba818ec2c15 100644
> > --- a/drivers/regulator/fp9931.c
> > +++ b/drivers/regulator/fp9931.c
> > @@ -444,7 +444,7 @@ static int fp9931_probe(struct i2c_client *client)
> >  		return dev_err_probe(&client->dev, PTR_ERR(data->regmap),
> >  				     "failed to allocate regmap!\n");
> >  
> > -	data->vin_reg = devm_regulator_get_optional(&client->dev, "vin");
> > +	data->vin_reg = devm_regulator_get(&client->dev, "vin");  
> 
> And this isn't an ABI break because the regulator core will invent a
> dummy regulator?
> 
On most devices I see a dummy regulator somewhere.

What IMHO itches more is that one has to invent a regulator in devicetree
if the property is mandatory and the supply is not known, you have to add
a dummy regulator in the devicetree to make dtbs_check happy.

Regards,
Andreas

Re: [PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Mark Brown]

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On Fri, Mar 13, 2026 at 09:31:00PM +0800, Robby Cai wrote:
> The FP9931 regulator requires a valid "vin" supply to operate correctly.
> Therefore, the driver should treat "vin" as a mandatory supply.
> 
> This patchset updates the binding documentation to mark vin-supply as a
> required property, and modifies the driver accordingly. As suggested in
> the reviews from Andreas and Mark, v2 switches to using
> devm_regulator_get() since the supply is mandatory.

Please do not submit new versions of already applied patches, please
submit incremental updates to the existing code.  Modifying existing
commits creates problems for other users building on top of those
commits so it's best practice to only change pubished git commits if
absolutely essential.

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Re: [PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Mark Brown]

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On Fri, Mar 13, 2026 at 01:31:23PM +0000, Mark Brown wrote:
> On Fri, Mar 13, 2026 at 09:31:00PM +0800, Robby Cai wrote:
> > The FP9931 regulator requires a valid "vin" supply to operate correctly.
> > Therefore, the driver should treat "vin" as a mandatory supply.

> > This patchset updates the binding documentation to mark vin-supply as a
> > required property, and modifies the driver accordingly. As suggested in
> > the reviews from Andreas and Mark, v2 switches to using
> > devm_regulator_get() since the supply is mandatory.

> Please do not submit new versions of already applied patches, please
> submit incremental updates to the existing code.  Modifying existing
> commits creates problems for other users building on top of those
> commits so it's best practice to only change pubished git commits if
> absolutely essential.

Your v1 was at the tip of the branch so I did actually just drop it, but
please don't do this.

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Re: [PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Robby Cai]

On Fri, Mar 13, 2026 at 04:27:21PM +0000, Mark Brown wrote:
> On Fri, Mar 13, 2026 at 01:31:23PM +0000, Mark Brown wrote:
> > On Fri, Mar 13, 2026 at 09:31:00PM +0800, Robby Cai wrote:
> > > The FP9931 regulator requires a valid "vin" supply to operate correctly.
> > > Therefore, the driver should treat "vin" as a mandatory supply.
> 
> > > This patchset updates the binding documentation to mark vin-supply as a
> > > required property, and modifies the driver accordingly. As suggested in
> > > the reviews from Andreas and Mark, v2 switches to using
> > > devm_regulator_get() since the supply is mandatory.
> 
> > Please do not submit new versions of already applied patches, please
> > submit incremental updates to the existing code.  Modifying existing
> > commits creates problems for other users building on top of those
> > commits so it's best practice to only change pubished git commits if
> > absolutely essential.
> 
> Your v1 was at the tip of the branch so I did actually just drop it, but
> please don't do this.

Thanks for the clarification.

Just to confirm: since you already dropped the v1 from your tree,
does that mean I should wait and only send an incremental patch
when there is a further change needed?

Regards,
Robby

Re: [PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Mark Brown]

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On Mon, Mar 16, 2026 at 03:31:25PM +0800, Robby Cai wrote:
> On Fri, Mar 13, 2026 at 04:27:21PM +0000, Mark Brown wrote:

> > Your v1 was at the tip of the branch so I did actually just drop it, but
> > please don't do this.

> Thanks for the clarification.

> Just to confirm: since you already dropped the v1 from your tree,
> does that mean I should wait and only send an incremental patch
> when there is a further change needed?

Yes, exactly.

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Re: [PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Mark Brown]

On Fri, 13 Mar 2026 21:31:00 +0800, Robby Cai wrote:
> regulator: fp9931: Make vin-supply mandatory
> 
> The FP9931 regulator requires a valid "vin" supply to operate correctly.
> Therefore, the driver should treat "vin" as a mandatory supply.
> 
> This patchset updates the binding documentation to mark vin-supply as a
> required property, and modifies the driver accordingly. As suggested in
> the reviews from Andreas and Mark, v2 switches to using
> devm_regulator_get() since the supply is mandatory.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-7.1

Thanks!

[1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required
      https://git.kernel.org/broonie/regulator/c/d342f5e355aa
[2/2] regulator: fp9931: Fix handling of mandatory "vin" supply
      https://git.kernel.org/broonie/regulator/c/58068932402c

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Re: [PATCH v2 0/2] regulator: fp9931: Make vin-supply mandatory

[Mark Brown]

On Fri, 13 Mar 2026 21:31:00 +0800, Robby Cai wrote:
> The FP9931 regulator requires a valid "vin" supply to operate correctly.
> Therefore, the driver should treat "vin" as a mandatory supply.
> 
> This patchset updates the binding documentation to mark vin-supply as a
> required property, and modifies the driver accordingly. As suggested in
> the reviews from Andreas and Mark, v2 switches to using
> devm_regulator_get() since the supply is mandatory.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next

Thanks!

[1/2] dt-bindings: regulator: fp9931: Make vin-supply property as required
      https://git.kernel.org/broonie/misc/c/d342f5e355aa
[2/2] regulator: fp9931: Fix handling of mandatory "vin" supply
      https://git.kernel.org/broonie/misc/c/58068932402c

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark