Re: [PATCH v3] net: phy: meson-gxl: Add generic dummy stubs for MMD register access

From: Heiner Kallweit
Date: Tue Jan 31 2023 - 05:38:50 EST


On 31.01.2023 11:05, Jerome Brunet wrote:
>
> On Mon 30 Jan 2023 at 15:14, Chris Healy <cphealy@xxxxxxxxx> wrote:
>
>> From: Chris Healy <healych@xxxxxxxxxx>
>>
>> The Meson G12A Internal PHY does not support standard IEEE MMD extended
>> register access, therefore add generic dummy stubs to fail the read and
>> write MMD calls. This is necessary to prevent the core PHY code from
>> erroneously believing that EEE is supported by this PHY even though this
>> PHY does not support EEE, as MMD register access returns all FFFFs.
>
> This is definitely something that should be done, Thx !
>
>>
>> Fixes: 5c3407abb338 ("net: phy: meson-gxl: add g12a support")
>
> This commit does not seems appropriate, especially since only the GXL ops
> are changed, not the g12a variant.
>
The diff is a little bit misleading. The patch affects the G12A PHY.

> This brings a 2nd point, any reason for not changing the g12 variant ?
> I'm fairly confident it does support EEE either.
>
Supposedly it's a typo and you mean "doesn't". Neither Chris nor me
have GXL HW and we didn't want to submit a patch just based on speculation.

>> Reviewed-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
>> Signed-off-by: Chris Healy <healych@xxxxxxxxxx>
>>
>> ---
>>
>> Changes in v3:
>> * Add reviewed-by
>> Change in v2:
>> * Add fixes tag
>>
>> drivers/net/phy/meson-gxl.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/net/phy/meson-gxl.c b/drivers/net/phy/meson-gxl.c
>> index c49062ad72c6..5e41658b1e2f 100644
>> --- a/drivers/net/phy/meson-gxl.c
>> +++ b/drivers/net/phy/meson-gxl.c
>> @@ -271,6 +271,8 @@ static struct phy_driver meson_gxl_phy[] = {
>> .handle_interrupt = meson_gxl_handle_interrupt,
>> .suspend = genphy_suspend,
>> .resume = genphy_resume,
>> + .read_mmd = genphy_read_mmd_unsupported,
>> + .write_mmd = genphy_write_mmd_unsupported,
>> },
>> };
>