Re: [PATCH v4 04/11] leds: aw200xx: calculate dts property display_rows in the driver

[Dmitry Rokosov]

Lee,

Thank you for the quick reply!

On Mon, Nov 27, 2023 at 08:57:55AM +0000, Lee Jones wrote:
> On Fri, 24 Nov 2023, Dmitry Rokosov wrote:
> 
> > On Thu, Nov 23, 2023 at 04:32:52PM +0000, Lee Jones wrote:
> > > On Tue, 21 Nov 2023, Dmitry Rokosov wrote:
> > > 
> > > > From: George Stark <gnstark@xxxxxxxxxxxxxxxxx>
> > > > 
> > > > Get rid of device tree property "awinic,display-rows". The property
> > > > value actually means number of current switches and depends on how leds
> > > 
> > > Nit: LEDs
> > > 
> > > > are connected to the device. It should be calculated manually by max
> > > > used led number. In the same way it is computed automatically now.
> > > 
> > > As above - I won't mention this again.
> > > 
> > > > Max used led is taken from led definition subnodes.
> > > > 
> > > > Signed-off-by: George Stark <gnstark@xxxxxxxxxxxxxxxxx>
> > > > Signed-off-by: Dmitry Rokosov <ddrokosov@xxxxxxxxxxxxxxxxx>
> > > > ---
> > > >  drivers/leds/leds-aw200xx.c | 39 +++++++++++++++++++++++++------------
> > > >  1 file changed, 27 insertions(+), 12 deletions(-)
> > > > 
> > > > diff --git a/drivers/leds/leds-aw200xx.c b/drivers/leds/leds-aw200xx.c
> > > > index 7762b3a132ac..4bce5e7381c0 100644
> > > > --- a/drivers/leds/leds-aw200xx.c
> > > > +++ b/drivers/leds/leds-aw200xx.c
> > > > @@ -379,6 +379,30 @@ static void aw200xx_disable(const struct aw200xx *const chip)
> > > >  	return gpiod_set_value_cansleep(chip->hwen, 0);
> > > >  }
> > > >  
> > > > +static bool aw200xx_probe_get_display_rows(struct device *dev, struct aw200xx *chip)
> > > > +{
> > > > +	struct fwnode_handle *child;
> > > > +	u32 max_source = 0;
> > > > +
> > > > +	device_for_each_child_node(dev, child) {
> > > > +		u32 source;
> > > > +		int ret;
> > > > +
> > > > +		ret = fwnode_property_read_u32(child, "reg", &source);
> > > > +		if (ret || source >= chip->cdef->channels)
> > > 
> > > Shouldn't the second clause fail instantly?
> > > 
> > 
> > We already have such logic in the aw200xx_probe_fw() function, which
> > skips the LED node with the wrong reg value too. Furthermore, we have
> > strict reg constraints in the dt-bindings parts (in the current patch
> > series), so we assume that the DT developer will not create an LED with
> > the wrong reg value.
> 
> Why is it being checked again then?

Hmmm, aw200xx_probe_get_display_rows() executes before the old
implementation... So we need to check it again. Do you think it should
be reworked? I've already sent a new patchset. Could you please take a
look at the other fixes?

-- 
Thank you,
Dmitry