Re: [PATCH] mfd: core: introduce of_node_name for mfd sub devices

[Laxman Dewangan <ldewangan@nvidia.com>]

On Thursday 19 September 2013 05:52 PM, Lee Jones wrote:
>>>>> Do the sub-nodes have their own properties? If so, it would be worth
>>>>> breaking them up as other OSes could reuse the specifics. If they do,
>>>>> then you need so put them in the binding. If they don't, then you do
>>>>> not require sub-nodes. The MFD core will ensure the sub-devices are
>>>>> probed and there is no requirement for the of_node to be assigned.
>>>> You do see some reusable IP blocks (like the regualtors on the wm831x
>>>> PMICs for example, they're repeated blocks) which can be reused but
>>>> generally they have a register base as part of the binding.  Personally
>>>> if it's just a property or two I'd probably just put them on the root
>>>> node for the device.
>>> Agreed. Besides, there doesn't seem to be *any* sub-device properties
>>> defined in the binding document. So what are you trying to achieve
>>> with the child nodes?
>> I wanted to have the DT like:
>>
>> as3722 {
>>                  compatible = "ams,as3722";
>>                  reg = <0x40>;
>>
>>                  #interrupt-controller;
>>                  .....
>>
>>
>>                  regulators {
>>                              ldo1-in-supply = <..>;
>>                              ....
>>                              sd0 {
>>                                      regulator-name = "vdd-cpu";
>>                                      .....
>>                              };
>>                              sd1 {
>>                                      regulator-name = "vdd-ddr";
>>                                      .....
>>                              };
>>                              ....
>>              };
>> };
>>
>> And regulator driver should get the regulator node by their
>> pdev->dev.of_node.
>> Currently, in most of driver, we are having the code on regulator
>> driver to get "regulators" node from parent node which I want to
>> avoid.
> Ah, I see. Yes, I believe the regulators should have their own node,
> complete with a compatible string. To have each regulator listed
> separately in the parent node seems a little messy. Just out of
> interest, how many regulators are we talking about here?
>
There is 7 DCDC step down and 10 LDOs.
It is more readable if sub-module properties are grouped and defined on 
different sub-node in place of having this in single parent node.