Pavel On 08/08/2018 04:45 PM, Pavel Machek wrote: > On Wed 2018-08-08 16:41:16, Dan Murphy wrote: >> On 08/08/2018 04:09 PM, Pavel Machek wrote: >>> On Wed 2018-08-08 16:04:43, Dan Murphy wrote: >>>> On 08/08/2018 04:02 PM, Pavel Machek wrote: >>>>> Hi! >>>>> >>>>>>>> + - #size-cells : 0 >>>>>>>> + - control-bank-cfg - : Indicates which sink is connected to which control bank >>>>>>>> + 0 - All HVLED outputs are controlled by bank A >>>>>>>> + 1 - HVLED1 is controlled bank B, HVLED2/3 are controlled by bank A >>>>>>>> + 2 - HVLED2 is controlled bank B, HVLED1/3 are controlled by bank A >>>>>>>> + 3 - HVLED1/2 are controlled by bank B, HVLED3 is controlled by bank A >>>>>>>> + 4 - HVLED3 is controlled by bank B, HVLED1/2 are controlled by bank A >>>>>>>> + 5 - HVLED1/3 is controlled by bank B, HVLED2 is controlled by bank A >>>>>>>> + 6 - (default) HVLED1 is controlled by bank A, HVLED2/3 are controlled by bank B >>>>>>>> + 7 - All HVLED outputs are controlled by bank B >>>>>>> >>>>>>> This is quite long way to describe a bitmask, no? Could we make >>>>>>> it so that control-bank-cfg is not needed? >>>>>> >>>>>> The problem we have here is there is a potential to control >>>>>> 3 different LED string but only 2 sinks. So control bank A can control 2 LED strings and control >>>>>> bank b can control 1 LED string. >>>>>> >>>>> >>>>> Can we forget about the LED strings, and just expose the sinks as >>>>> Linux LED devices? >>>> >>>> 2 sinks 3 LED strings. How do you know which LED string is which and what bank it belongs >>>> to when setting the brightness. Each Bank has a separate register for brightness control. >>> >>> Yes, and LED strings are statically assigned to banks, right? >>> >>> So why not simply forget about LED strings for sake of hw >>> abstractions, and work just with banks? >> >> How would you set the control bank register for the correct LED string configuration? > > Have property at each LED saying which which HVLEDs it controls? Isn't that what I have already using the reg property? Then we would have to aggregate the configuration and make a determination in the driver. But that does not follow the LED child node ideology. Each output of the LED driver should have a child node. In this case the outputs are the sinks(inputs) and there are only 2 sinks so having 3 LED child nodes would be confusing and there are required properties for each child like label. Each child node would then need to present 1 LED node to the user space to control the LED string. Which would be technically incorrect because you would have 2 LED nodes controlling the same control bank sink. > > Pavel > -- ------------------ Dan Murphy -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
