Re: [PATCH v6 1/3] phy: core: Reword the comment specifying the units of max_link_rate to be Mbps

From: Aswath Govindraju
Date: Mon May 31 2021 - 04:34:46 EST


Hi Vinod,

On 31/05/21 12:48 pm, Vinod Koul wrote:
> On 10-05-21, 10:40, Aswath Govindraju wrote:
>> In some subsystems (eg. CAN, SPI), the max link rate supported can be less
>> than 1 Mbps and if the unit for max_link_rate is Mbps then it can't be
>> used. Therefore, leave the decision of units to be used, to the producer
>> and consumer.
>>
>> Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx>
>> Acked-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
>> ---
>> include/linux/phy/phy.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
>> index 0ed434d02196..f3286f4cd306 100644
>> --- a/include/linux/phy/phy.h
>> +++ b/include/linux/phy/phy.h
>> @@ -125,7 +125,7 @@ struct phy_ops {
>> /**
>> * struct phy_attrs - represents phy attributes
>> * @bus_width: Data path width implemented by PHY
>> - * @max_link_rate: Maximum link rate supported by PHY (in Mbps)
>> + * @max_link_rate: Maximum link rate supported by PHY (units to be decided by producer and consumer)
>
> So there are a few users of max_link_rate. It would be better that we
> document all previous users of max_link_rate that unit is in Mbps and
> then modify it here
>

I was able to see that the max_link_rate attribute was used at,

drivers/phy/cadence/phy-cadence-torrent.c:2514:
gphy->attrs.max_link_rate = cdns_phy->max_bit_rate;

and in the bindings there is indication that the units to be used is Mbps.

Can you please point me if there is any other place that I might have
missed to look at or that might need documentation update?

Thanks,
Aswath