Re: [PATCH v5 4/4] net: stmmac: Update the name of property 'clk_csr'

From: AngeloGioacchino Del Regno
Date: Tue Sep 27 2022 - 06:44:58 EST


Il 27/09/22 10:44, Jianguo Zhang ha scritto:
Dear Krzysztof,
Thanks for your comment.

On Fri, 2022-09-23 at 20:15 +0200, Krzysztof Kozlowski wrote:
On 23/09/2022 20:14, Krzysztof Kozlowski wrote:
This is going to break MT2712e on old devicetrees.

The right way of doing that is to check the return value of
of_property_read_u32()
for "snps,clk-csr": if the property is not found, fall back to
the old "clk_csr".

I must admit - I don't care. That's the effect when submitter
bypasses
DT bindings review (81311c03ab4d ("net: ethernet: stmmac: add
management
of clk_csr property")).

If anyone wants ABI, please document the properties.

If out-of-tree users complain, please upstream your DTS or do not
use
undocumented features...


OTOH, as Angelo pointed out, handling old and new properties is quite
easy to achieve, so... :)

So, the conclusion is as following:

1. add new property 'snps,clk-csr' and document it in binding file.
2. parse new property 'snps,clk-csr' firstly, if failed, fall back to
old property 'clk_csr' in driver.

Is my understanding correct?

Yes, please.

I think that bindings should also get a 'clk_csr' with deprecated: true,
but that's Krzysztof's call.

Regards,
Angelo


Best regards,
Krzysztof

BRS
Jianguo