Re: [PATCH] arm64: dts: mt7622: fix switch probe on bananapi-r64

From: Frank Wunderlich
Date: Fri May 31 2024 - 02:18:31 EST


Am 31. Mai 2024 08:12:06 MESZ schrieb "Arınç ÜNAL" <arinc.unal@xxxxxxxxxx>:
>On 17/05/2024 09.27, Frank Wunderlich wrote:
>> Am 17. Mai 2024 04:17:47 MESZ schrieb "Arınç ÜNAL" <arinc.unal@xxxxxxxxxx>:
>>> On 16/05/2024 23:48, Frank Wunderlich wrote:
>>>> From: Frank Wunderlich <frank-w@xxxxxxxxxxxxxxx>
>>>>
>>>> After commit 868ff5f4944a
>>>> ("net: dsa: mt7530-mdio: read PHY address of switch from device tree")
>>>> the mt7531 switch on Bananapi-R64 was not detected.
>>>>
>>>> mt7530-mdio mdio-bus:00: reset timeout
>>>> mt7530-mdio mdio-bus:00: probe with driver mt7530-mdio failed with error -110
>>>>
>>>> Fix this by adding phy address in devicetree.
>>>>
>>>> Signed-off-by: Frank Wunderlich <frank-w@xxxxxxxxxxxxxxx>
>>>
>>> I don't like the mention of the Linux kernel driver on the patch log. What
>>> you're fixing is the incorrect description of the switch's PHY address on
>>> the DTS file. Whether or not any driver from any project is actually
>>> reading it from the DTS file is irrelevant to this patch. That said, I
>>> already have a patch series I've been meaning to send the next version of
>>> that already addresses this. Please wait for that.
>>>
>>> Arınç
>>
>> Hi arinc,
>>
>> From my PoV it is a regression in next/6.10 because the driver change was merged (without "broadcast" fallback) and the dts patch [1] is not.
>
>What is a broadcast fallback? 0x1f is just another PHY address.

Afaik 0x0 is some kind of broadcast address if real phy address is not known. The driver change seems not allow this 0x0 adress and forces devicetree to have the real address.

Thats what i mean with broadcast fallback. Maybe the naming is wrong.

>Arınç

@thorsten i have not tested again,but i have not seen any further fix for it.
regards Frank