[RFC PATCHv2 0/4] Add DT support for fixed PHYs

Christian Gmeiner christian.gmeiner at gmail.com
Mon Feb 10 05:30:30 EST 2014

2013-09-25 9:12 GMT+02:00 Christian Gmeiner <christian.gmeiner at gmail.com>:
> Hi
>>> Hello,
>>> Here is a second version of the patch set that adds a Device Tree
>>> binding and the related code to support fixed PHYs. Marked as RFC,
>>> this patch set is obviously not intended for merging in 3.12.
>>> Since the first version, the changes have been:
>>>  * Instead of using a 'fixed-link' property inside the Ethernet device
>>>    DT node, with a fairly cryptic succession of integer values, we now
>>>    use a PHY subnode under the Ethernet device DT node, with explicit
>>>    properties to configure the duplex, speed, pause and other PHY
>>>    properties.
>>>  * The PHY address is automatically allocated by the kernel and no
>>>    longer visible in the Device Tree binding.
>>>  * The PHY device is created directly when the network driver calls
>>>    of_phy_connect_fixed_link(), and associated to the PHY DT node,
>>>    which allows the existing of_phy_connect() function to work,
>>>    without the need to use the deprecated of_phy_connect_fixed_link().
>>> The things I am not entirely happy with yet are:
>>>  * The PHY ID is hardcoded to 0xdeadbeef. Ideally, it should be a
>>>    properly reserved vendor/device identifier, but it isn't clear how
>>>    to get one allocated for this purpose.
>>>  * The fixed_phy_register() function in drivers/net/phy/fixed.c has
>>>    some OF references. So ideally, I would have preferred to put this
>>>    code in drivers/of/of_mdio.c, but to call get_phy_device(), we need
>>>    a reference to the mii_bus structure that represents the fixed MDIO
>>>    bus.
>>>  * There is some error management missing in fixed_phy_register(), but
>>>    it can certainly be added easily. This RFC is meant to sort out the
>>>    general idea.
>> +1 for the general idea. This really looks good now. I've not much more
>> to say. Maybe someone from the devicetree corner has a few words for the
>> binding?
> I tested the whole series with an I.MX6D board with the FEC driver:
> fec 2188000.ethernet eth0: Freescale FEC PHY driver [Generic PHY]
> (mii_bus:phy_addr=fixed-0:00, irq=-1)
> For me binding looks nice and I hope to see this patch series in 3.13.
> Tested-by: Christian Gmeiner <christian.gmeiner at gmail.com>

Is there any update on this patch series?

Christian Gmeiner, MSc


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