Re: Registering IRQ for MT7530 internal PHYs

From: Heiner Kallweit
Date: Wed Dec 30 2020 - 11:54:46 EST


On 30.12.2020 17:15, Florian Fainelli wrote:
>
>
> On 12/30/2020 1:12 AM, Heiner Kallweit wrote:
>> On 30.12.2020 10:07, DENG Qingfang wrote:
>>> Hi Heiner,
>>> Thanks for your reply.
>>>
>>> On Wed, Dec 30, 2020 at 3:39 PM Heiner Kallweit <hkallweit1@xxxxxxxxx> wrote:
>>>> I don't think that's the best option.
>>>
>>> I'm well aware of that.
>>>
>>>> You may want to add a PHY driver for your chip. Supposedly it
>>>> supports at least PHY suspend/resume. You can use the RTL8366RB
>>>> PHY driver as template.
>>>
>>> There's no MediaTek PHY driver yet. Do we really need a new one just
>>> for the interrupts?
>>>
>> Not only for the interrupts. The genphy driver e.g. doesn't support
>> PHY suspend/resume. And the PHY driver needs basically no code,
>> just set the proper callbacks.
>
> That statement about not supporting suspend/resume is not exactly true,
> the generic "1g" PHY driver only implements suspend/resume through the
> use of the standard BMCR power down bit, but not anything more
> complicated than that.
>
Oh, right. Somehow I had in the back of my mind that the genphy driver
has no suspend/resume callbacks set.

> Interrupt handling within the PHY itself is not defined by the existing
> standard registers and will typically not reside in a standard register
> space either, so just for that reason you do need a custom PHY driver.
> There are other advantages if you need to expose additional PHY features
> down the road like PHY counters, energy detection, automatic power down etc.
>
> I don't believe we will see discrete/standalone Mediatek PHY chips, but
> if that happens, then you would already have a framework for supporting
> them.
>