[Linux-stm32] [net-next PATCH v5 05/10] net: pcs: lynx: Convert to an MDIO driver

[Sean Anderson]

On 5/23/25 17:39, Sean Anderson wrote:
> On 5/23/25 17:33, Heiner Kallweit wrote:
>> On 23.05.2025 22:33, Sean Anderson wrote:
>>> This converts the lynx PCS driver to a proper MDIO driver.
>>> This allows using a more conventional driver lifecycle (e.g. with a
>>> probe and remove). It will also make it easier to add interrupt support.
>>> 
>>> The existing helpers are converted to bind the MDIO driver instead of
>>> creating the PCS directly. As lynx_pcs_create_mdiodev creates the PCS
>>> device, we can just set the modalias. For lynx_pcs_create_fwnode, we try
>>> to get the PCS the usual way, and if that fails we edit the devicetree
>>> to add a compatible and reprobe the device.
>>> 
>>> To ensure my contributions remain free software, remove the BSD option
>>> from the license. This is permitted because the SPDX uses "OR".
>>> 
>>> Signed-off-by: Sean Anderson <sean.anderson at linux.dev>
>>> ---
>>> 
>>> Changes in v5:
>>> - Use MDIO_BUS instead of MDIO_DEVICE
>>> 
>>> Changes in v4:
>>> - Add a note about the license
>>> - Convert to dev-less pcs_put
>>> 
>>> Changes in v3:
>>> - Call devm_pcs_register instead of devm_pcs_register_provider
>>> 
>>> Changes in v2:
>>> - Add support for #pcs-cells
>>> - Remove unused variable lynx_properties
>>> 
>>>  drivers/net/dsa/ocelot/Kconfig                |   4 +
>>>  drivers/net/dsa/ocelot/felix_vsc9959.c        |  11 +-
>>>  drivers/net/dsa/ocelot/seville_vsc9953.c      |  11 +-
>>>  drivers/net/ethernet/altera/Kconfig           |   2 +
>>>  drivers/net/ethernet/altera/altera_tse_main.c |   7 +-
>>>  drivers/net/ethernet/freescale/dpaa/Kconfig   |   2 +-
>>>  drivers/net/ethernet/freescale/dpaa2/Kconfig  |   3 +
>>>  .../net/ethernet/freescale/dpaa2/dpaa2-mac.c  |  11 +-
>>>  drivers/net/ethernet/freescale/enetc/Kconfig  |   2 +
>>>  .../net/ethernet/freescale/enetc/enetc_pf.c   |   8 +-
>>>  .../net/ethernet/freescale/enetc/enetc_pf.h   |   1 -
>>>  .../freescale/enetc/enetc_pf_common.c         |   4 +-
>>>  drivers/net/ethernet/freescale/fman/Kconfig   |   4 +-
>>>  .../net/ethernet/freescale/fman/fman_memac.c  |  25 ++--
>>>  drivers/net/ethernet/stmicro/stmmac/Kconfig   |   3 +
>>>  .../ethernet/stmicro/stmmac/dwmac-socfpga.c   |   6 +-
>>>  drivers/net/pcs/Kconfig                       |  11 +-
>>>  drivers/net/pcs/pcs-lynx.c                    | 110 ++++++++++--------
>>>  include/linux/pcs-lynx.h                      |  13 ++-
>>>  19 files changed, 128 insertions(+), 110 deletions(-)
>>> 
>>> diff --git a/drivers/net/dsa/ocelot/Kconfig b/drivers/net/dsa/ocelot/Kconfig
>>> index 081e7a88ea02..907c29d61c14 100644
>>> --- a/drivers/net/dsa/ocelot/Kconfig
>>> +++ b/drivers/net/dsa/ocelot/Kconfig
>>> @@ -42,7 +42,9 @@ config NET_DSA_MSCC_FELIX
>>>  	select NET_DSA_TAG_OCELOT_8021Q
>>>  	select NET_DSA_TAG_OCELOT
>>>  	select FSL_ENETC_MDIO
>>> +	select PCS
>>>  	select PCS_LYNX
>>> +	select MDIO_BUS
>> 
>> This shouldn't be needed. NET_DSA selects PHYLINK, which selects PHYLIB,
>> which selects MDIO_BUS. There are more places in this series where the
>> same comment applies.
> 
> select does not transitively enable dependencies. See the note in
> Documentation/kbuild/kconfig-language.rst for details. Therefore we must
> select the dependencies of things we select in order to ensure we do not
> trip sym_warn_unmet_dep.

OK, I see what you mean here. But of course NET_DSA is missing selects for
PHYLIB and MDIO_BUS. And PHYLINK is also missing a select for MDIO_BUS. Actually,
this bug is really endemic. Maybe we should just get rid of PHYLIB as a config
and just make everything depend on ETHERNET instead.

--Sean