Re: [PATCH 3/5] dt-binding: Add Qualcomm WCNSS control binding
From: Bjorn Andersson <hidden>
Date: 2016-03-31 18:24:56
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linux-arm-msm, lkml
On Thu 31 Mar 10:38 PDT 2016, Rob Herring wrote:
On Thu, Mar 31, 2016 at 12:16 PM, Bjorn Andersson [off-list ref] wrote:quoted
On Thu 31 Mar 07:28 PDT 2016, Rob Herring wrote:quoted
On Mon, Mar 28, 2016 at 09:35:24PM -0700, Bjorn Andersson wrote:[..][...]quoted
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+ +== 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?
So far I've only found cases where we need to know the register map for the DMA engine shuffling packets, so this is related to the SoC-internal part only. The differences in RF capabilities - at least for WiFi - seems to be acquired in runtime from the firmware. The other piece that depend on the RF part seems to be the availability of e.g. ANT support, so if anything that needs to go into the wcnss node, in some way (either compatible or the set of subnodes).
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+ +- qcom,wcnss-mmio: + Usage: required + Value type: <prop-encoded-array> + Definition: should specify base address and size of the WiFi related + registers of WCNSSThis 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.
Okay, sounds reasonable. I don't see a need for a specific implementation, so I'll just back it with the generic syscon implementation (and a specific compatible). Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html