Re: [PATCH] leds: leds-lp50xx: allow LED 0 to be added to module bank

[Jacek Anaszewski]

On 10/13/25 10:54, Christian Hitz wrote:
> On Sat, 11 Oct 2025 14:16:16 +0200 Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx> wrote:
>
> > Hi Christian,
> >
> > On 10/8/25 14:32, Christian Hitz wrote:
> > > From: Christian Hitz <christian.hitz@xxxxxx>
> > >
> > > led_banks contains LED module number(s) that should be grouped into the
> > > module bank. led_banks is 0-initialized.
> > > By checking the led_banks entries for 0, un-set entries are detected.
> > > But a 0-entry also indicates that LED module 0 should be grouped into the
> > > module bank.
> > >
> > > By only iterating over the available entries no check for unused entries
> > > is required and LED module 0 can be added to bank.
> > >
> > > Signed-off-by: Christian Hitz <christian.hitz@xxxxxx>
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > ---
> > >    drivers/leds/leds-lp50xx.c | 10 ++++------
> > >    1 file changed, 4 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/leds/leds-lp50xx.c b/drivers/leds/leds-lp50xx.c
> > > index 94f8ef6b482c..d50c7f3e8f99 100644
> > > --- a/drivers/leds/leds-lp50xx.c
> > > +++ b/drivers/leds/leds-lp50xx.c
> > > @@ -341,17 +341,15 @@ static int lp50xx_brightness_set(struct led_classdev *cdev,
> > >    	return ret;
> > >    }
> > >    
> > > -static int lp50xx_set_banks(struct lp50xx *priv, u32 led_banks[])
> > > +static int lp50xx_set_banks(struct lp50xx *priv, u32 led_banks[], int num_leds)
> > >    {
> > >    	u8 led_config_lo, led_config_hi;
> > >    	u32 bank_enable_mask = 0;
> > >    	int ret;
> > >    	int i;
> > >    
> > > -	for (i = 0; i < priv->chip_info->max_modules; i++) {
> > > -		if (led_banks[i])
> > > -			bank_enable_mask |= (1 << led_banks[i]);
> > > -	}
> > > +	for (i = 0; i < num_leds; i++)
> > > +		bank_enable_mask |= (1 << led_banks[i]);
> >
> > Probably the first idea was to have a bitmask indicating which bank
> > to enable, but it ended up in having array of bank ids in DT with no
> > related adjustment in the driver.
> >
> > This patch deserves Fixes tag.
>
> This code has not changed since the inital introduction of this driver.

Yeah, I had on mind design approach changes between subsequent
versions of the patch that was adding the driver.

> Fixes: 242b81170fb8 ("leds: lp50xx: Add the LP50XX family of the RGB LED driver")
--
Best regards,
Jacek Anaszewski