Re: [PATCH v14 13/19] leds: lp55xx: Add multicolor framework support to lp55xx

[Dan Murphy]

Jacek

On 10/25/19 1:56 PM, Jacek Anaszewski wrote:
> Dan,
>
> On 10/25/19 8:18 PM, Dan Murphy wrote:
> > Jacek
> >
> > On 10/25/19 1:13 PM, Jacek Anaszewski wrote:
> > > Dan,
> > >
> > > On 10/25/19 7:57 PM, Dan Murphy wrote:
> > > > Jacek
> > > >
> > > > On 10/22/19 12:41 PM, Jacek Anaszewski wrote:
> > > > > Dan,
> > > > >
> > > > > On 10/22/19 6:37 PM, Dan Murphy wrote:
> > > > > > Jacek
> > > > > >
> > > > > > On 10/18/19 4:56 PM, Jacek Anaszewski wrote:
> > > > > > > On 10/18/19 11:48 PM, Jacek Anaszewski wrote:
> > > > > > > > Dan,
> > > > > > > +ÂÂÂÂÂÂÂ ret = lp5xx_parse_channel_child(child, cfg, i);
> > > > > > > > I went into details of this parsing and finally came up with
> > > > > > > > the code which is a bit greater in size, but IMHO cleaner.
> > > > > > > > Note changes in variable naming. It is not even compile-tested.
> > > > > > > >
> > > > > > > > static int lp55xx_parse_common_child(struct device_node *np,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct lp55xx_led_config
> > > > > > > > *cfg,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int led_number, int *chan_nr)
> > > > > > > > {
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ int ret;
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ of_property_read_string(np, "chan-name",
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &cfg[led_number].name);
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ of_property_read_u8(np, "led-cur",
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &cfg[led_number].led_current);
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ of_property_read_u8(np, "max-cur",
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &cfg[led_number].max_current);
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ ret = of_property_read_u32(np, "reg", chan_nr);
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ if (ret)
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ return ret;
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ if (chan_nr < 0 || chan_nr > cfg->max_chan_nr) /* side
> > > > > > > > note:
> > > > > > > > new
> > > > > > > > max_chan_nr property needed in cfg */
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ return -EINVAL;
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ return 0;
> > > > > > > > }
> > > > > > > >
> > > > > > > > static int lp55xx_parse_mutli_led_child(struct device_node *np,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct lp55xx_led_config
> > > > > > > > *cfg,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int child_number,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int color_number)
> > > > > > > > {
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ int chan_nr, color_id;
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ ret = lp55xx_parse_common_child(child, cfg, child_number,
> > > > > > > > color_number,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &chan_nr);
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ if (ret)
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ return ret;
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ ret = of_property_read_u32(child, "color", &color_id);
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ if (ret)
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ return ret;
> > > > > > > >
> > > > > > > >            
> > > > > > > > cfg[child_number].color_components[color_number].color_id =
> > > > > > > > color_id;
> > > > > > > >           
> > > > > > > > cfg[child_number].color_components[color_number].output_num =
> > > > > > > > chan_nr;
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ set_bit(color_id, &cfg[child_number].available_colors);
> > > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ return 0;
> > > > > > > > }
> > > > > > > >
> > > > > > > > staitc int lp55xx_parse_mutli_led(struct device_node *np,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct lp55xx_led_config *cfg,
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int child_number)
> > > > > > > > {
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ struct device_node *child;
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ int num_colors = 0, i = 0;
> > > > > > > s/, i = 0//
> > > > > > >
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂ for_each_child_of_node(np, child) {
> > > > > > > >  ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ ret = lp55xx_parse_mutli_led_child(child, cfg,
> > > > > > > > num_colors,
> > > > > > > >                                                       
> > > > > > > > child_number, i))
> > > > > > > Replace above call with below:
> > > > > > >
> > > > > > > ret = lp55xx_parse_mutli_led_child(child, cfg, child_number,
> > > > > > > num_colors);
> > > > > > I applied your DT parser patch from the v13 series. Which eliminates
> > > > > > this comment correct?
> > > > > Yes, it contains this fix.
> > > > OK I added your patch and it broke a lot of the DT parsing for the
> > > > LP55xx.
> > > >
> > > > I would prefer to stick with the original code without having to
> > > > re-write this again.
> > > Let me test that with Qemu first.
> > max_channel is never set so not sure where that is supposed to come from
> > since each child device has different number of channels. And if the
> > user has to populate that information from the DT then it does not make
> > sense as the user would already be aware of the number of channels.
> > This information would have to come from the child device some how and
> > the children do not have access to the structure to set it.
> This was my silent assumption that the child will initialize that.
> And I was not thoroughly seeking the most proper place for this
> property, just chose first I could think . You are free to
> change its location so that it was accessible for the child.
OKÂ I got it limping along now by passing in the chip->cfg to the 
populate data along with rearranging the child probe.

I think it is a lot of change to check 1 value but I can include it

> > In checking the chan_nr to the max_channels you are comparing a pointer
> > to an integer. Easy fix but did not solve the registration issues.
> >
> > cfg->num_colors is not set anywhere so the registration always goes to
> > base led_registration. Unless we key off a different value to determine
> > to register to multicolor class or not. Or we default this to the
> > multi_class registration to figure out how to register based on
> > available_colors.
> You need to add below at the end of lp55xx_parse_mutli_led():
>
> cfg[child_number].num_colors = num_colors;
>
> and below in led_parse_logical_led() at the end of the
> "if (ret)" branch.
>
> cfg[child_number].num_colors = 1;

This was added

> > That is what I am seeing so far in my debugging and I still don't have
> > it working.
> I didn't pretend it was flawless, just wanted to show general idea
> how I would see that.
Yes I know you only compile tested this.

Dan