Re: [PATCH v2] of_net: Implement of_get_nvmem_mac_address helper

[Mike Looijmans <mike.looijmans@topic.nl>]

On 26-03-18 17:50, Andrew Lunn wrote:
> On Mon, Mar 26, 2018 at 08:41:29AM +0200, Mike Looijmans wrote:
>> It's common practice to store MAC addresses for network interfaces into
>> nvmem devices. However the code to actually do this in the kernel lacks,
>> so this patch adds of_get_nvmem_mac_address() for drivers to obtain the
>> address from an nvmem cell provider.
>>
>> This is particulary useful on devices where the ethernet interface cannot
>> be configured by the bootloader, for example because it's in an FPGA.
>>
>> Tested by adapting the cadence macb driver to call this instead of
>> of_get_mac_address().
> 
> Hi Mike
> 
> I can understand you not wanting to modify all the call sites for
> of_get_mac_address().
> 
> However, the name of_get_nvmem_mac_address() suggests it gets the MAC
> address from NVMEM. I think people are going to be surprised when they
> find it first tries for a MAC address directly in device tree. I would
> drop the call to of_get_mac_address(), and have the MAC driver call
> both.
> 
> You could also maybe take a look at fwnode_get_mac_address(). It
> should work for both OF and ACPI. It fits better because is passes a
> char * for the address. You could make that do both, and call it from
> the macb driver. dev_fwnode() probably does what you want.

fwnode_get_mac_address looks really new, there's only one user so far. 
Is it the intention that all drivers eventually migrate to that?

(It also means I cannot backport it to the kernel I'm actually using, 
'cause I haven't got the Zynq to work with the mainline macb driver yet. 
But that's just my problem...)

-- 
Mike Looijmans