iio: adc: PAC1934: Fix clamped value in pac1934_reg_snapshot

[PATCH] iio: adc: PAC1934: Fix clamped value in pac1934_reg_snapshot

Posted by Thorsten Blum 2 weeks, 3 days ago

The local variable 'curr_energy' was never clamped to
PAC_193X_MIN_POWER_ACC or PAC_193X_MAX_POWER_ACC because the return
value of clamp() was not used. Fix this by assigning the clamped value
back to 'curr_energy'.

Cc: stable@vger.kernel.org
Fixes: 0fb528c8255b ("iio: adc: adding support for PAC193x")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 drivers/iio/adc/pac1934.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/pac1934.c b/drivers/iio/adc/pac1934.c
index 48df16509260..256488d3936b 100644
--- a/drivers/iio/adc/pac1934.c
+++ b/drivers/iio/adc/pac1934.c
@@ -665,7 +665,8 @@ static int pac1934_reg_snapshot(struct pac1934_chip_info *info,
 			/* add the power_acc field */
 			curr_energy += inc;
 
-			clamp(curr_energy, PAC_193X_MIN_POWER_ACC, PAC_193X_MAX_POWER_ACC);
+			curr_energy = clamp(curr_energy, PAC_193X_MIN_POWER_ACC,
+					    PAC_193X_MAX_POWER_ACC);
 
 			reg_data->energy_sec_acc[cnt] = curr_energy;
 		}
-- 
Thorsten Blum <thorsten.blum@linux.dev>
GPG: 1D60 735E 8AEF 3BE4 73B6  9D84 7336 78FD 8DFE EAD4

Re: [PATCH] iio: adc: PAC1934: Fix clamped value in pac1934_reg_snapshot

Posted by Andy Shevchenko 2 weeks, 3 days ago

On Tue, Dec 2, 2025 at 8:13 PM Thorsten Blum <thorsten.blum@linux.dev> wrote:
>
> The local variable 'curr_energy' was never clamped to
> PAC_193X_MIN_POWER_ACC or PAC_193X_MAX_POWER_ACC because the return
> value of clamp() was not used. Fix this by assigning the clamped value
> back to 'curr_energy'.

...

>                         /* add the power_acc field */
>                         curr_energy += inc;
>
> -                       clamp(curr_energy, PAC_193X_MIN_POWER_ACC, PAC_193X_MAX_POWER_ACC);
> +                       curr_energy = clamp(curr_energy, PAC_193X_MIN_POWER_ACC,
> +                                           PAC_193X_MAX_POWER_ACC);
>
>                         reg_data->energy_sec_acc[cnt] = curr_energy;

Hmm... Maybe

                       reg_data->energy_sec_acc[cnt] = clamp(curr_energy,
                                           PAC_193X_MIN_POWER_ACC,
                                           PAC_193X_MAX_POWER_ACC);

?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] iio: adc: PAC1934: Fix clamped value in pac1934_reg_snapshot

Posted by Jonathan Cameron 1 week, 5 days ago

On Tue, 2 Dec 2025 20:47:37 +0200
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Tue, Dec 2, 2025 at 8:13 PM Thorsten Blum <thorsten.blum@linux.dev> wrote:
> >
> > The local variable 'curr_energy' was never clamped to
> > PAC_193X_MIN_POWER_ACC or PAC_193X_MAX_POWER_ACC because the return
> > value of clamp() was not used. Fix this by assigning the clamped value
> > back to 'curr_energy'.  
> 
> ...
> 
> >                         /* add the power_acc field */
> >                         curr_energy += inc;
> >
> > -                       clamp(curr_energy, PAC_193X_MIN_POWER_ACC, PAC_193X_MAX_POWER_ACC);
> > +                       curr_energy = clamp(curr_energy, PAC_193X_MIN_POWER_ACC,
> > +                                           PAC_193X_MAX_POWER_ACC);
> >
> >                         reg_data->energy_sec_acc[cnt] = curr_energy;  
> 
> Hmm... Maybe
> 
>                        reg_data->energy_sec_acc[cnt] = clamp(curr_energy,
>                                            PAC_193X_MIN_POWER_ACC,
>                                            PAC_193X_MAX_POWER_ACC);
I went with aligning after ( and slightly longer than 80 char lines.
other combinations didn't seem to read quite as well to me.

Applied to the fixes-togreg branch of iio.git.  I'll probably sit on pushing
that out until I can rebase on rc1 however.

Jonathan

> 
> ?
>