Re: [PATCH 5/9] clk: qcom: gcc-msm8960: add child devices support.

[Rajendra Nayak <rnayak@codeaurora.org>]

[]..
>>>> Also, I don't like having a subnode in DT. Why can't we use the
>>>> same node as the GCC node and create a virtual child device here
>>>> for tsens? We can assign the same of_node that this platform
>>>> device has so that DT keeps working correctly.
>>
>> So the current driver looks up data based on compatible strings.
>
> The tsens device is always the same piece of hardware. The only

Well, not always. The one in 8960 does need additional initializations,
requires you to save/restore context as it can be powered off
not being in an always powered on domain etc.

> thing that's changing is the qfprom data and the number of
> sensors. So we should be looking at the qfprom compatible string

How? Tsens uses nvmem framework apis to read the qfprom atleast
in this series.

> to figure out how to interpret the qfprom data which would
> include the number of sensors and how the data is encoded.
>
>> So you suggesting to create a virtual child device for gcc and
>> associate the gcc DT node to it? (And have the tsens compatible
>> mentioned as part of the gcc DT node?)
>
> No. The driver should work just fine without having to
> interrogate the device's compatible string. If we still need the
> compatible check for some reason, then we can always match based
> on qcom,gcc-msm8960, qcom,gcc-apq8064, etc. But I don't see why

Thats not quite possible I guess. 2 drivers (gcc and tsens) matching
the same compatibles? Will it not just depend on which ends up being
the first match?

> we need to do that when we should be looking at what type of
> qfprom is connected so we can correctly parse the data.