Re: Add driver for MCP45HV51 (digital potentiometer)

["Gaëtan Carlier" <gcembed@gmail.com>]

On 01/03/2018 08:25 PM, Gaëtan Carlier wrote:
> On 01/03/2018 08:00 PM, Pavel Machek wrote:
>> On Wed 2018-01-03 19:38:31, Gaëtan Carlier wrote:
>>> Hi Pavel,
>>> On 01/03/2018 06:56 PM, Pavel Machek wrote:
>>>> Hi!
>>>>
>>>>> I want to integrate MCP45HV51 I2C device to Linux kernel. It is a 
>>>>> digital
>>>>> potentiometer.
>>>>> I have several questions:
>>>>> - Is "leds driver" the correct section ?
>>>>> - On which existing I2C leds driver should I base my code to use 
>>>>> the most
>>>>> recent API/pratice ?
>>>>> - Maybe it is not needed to write a C driver and everything can be 
>>>>> done via
>>>>> devicetree ?
>>>>
>>>> Umm. What makes you think that LED driver is correct section? LEDs are
>>>> little lights...
>>>
>>> I know that, but like Led and Backlight, digital potentiometers are 
>>> just a
>>> device that needs a 0 to 255 value...
>>> So I don't know where to put it maybe in IIO driver ?
>>
>> Is that _output_ device? What does it control?
>>
>>                                     Pavel
>>
> 
> It is an output with a variable resistance (like DAC is an output with a 
> variable voltage).[1]
> So regarding the webpage of IIO[2], digital potentiometer must be coded 
> on IIO API.
> 
> Thank you taking time to answer me,
> Gaëtan.
> 
> 
> [1] https://en.wikipedia.org/wiki/Digital_potentiometer
> [2] https://wiki.analog.com/software/linux/docs/iio/iio
After a deeper search on a recent branch, potentiometer are already 
handled in IIO layer :D