Re: [PATCH 3/5] dt-binding: Add Qualcomm WCNSS control binding

From: Rob Herring
Date: Thu Mar 31 2016 - 13:38:40 EST


On Thu, Mar 31, 2016 at 12:16 PM, Bjorn Andersson
<bjorn.andersson@xxxxxxxxxx> wrote:
> On Thu 31 Mar 07:28 PDT 2016, Rob Herring wrote:
>
>> On Mon, Mar 28, 2016 at 09:35:24PM -0700, Bjorn Andersson wrote:
> [..]

[...]

>> > +
>> > +== WiFi
>> > +The following properties are defined to the WiFi node:
>> > +
>> > +- compatible:
>> > + Usage: required
>> > + Value type: <string>
>> > + Definition: must be one of:
>> > + "qcom,wcn3620-wlan",
>> > + "qcom,wcn3660-wlan",
>> > + "qcom,wcn3680-wlan"
>
> Digging through documentation and trying to answer the questions above
> made me realize that these numbers are for the external rf component,
> not the variants of the logic inside the SoC; and as such wrong.

Do you need to know both? Or only the firmware image needs to know?

>> > +
>> > +- qcom,wcnss-mmio:
>> > + Usage: required
>> > + Value type: <prop-encoded-array>
>> > + Definition: should specify base address and size of the WiFi related
>> > + registers of WCNSS
>>
>> This is an address visible to the cpu?
>>
>
> Yes it is; the device is controlled both through SMD and mmio accessible
> registers, where the SMD interface is the primary interface.
>
> SMD being the primary "bus" I believe I can't use reg to denote this
> register range. Should I describe this in some other form?

That's a tricky one. I would create a node for the memory-mapped
portion with proper compatible and reg properties, and then make this
a phandle to that node. Something similar to how we do phandles to
syscon's.

Rob