From: wg@grandegger•com (Wolfgang Grandegger)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] net: fec: Add support for multiple phys on mdiobus
Date: Mon, 21 Jan 2013 12:07:30 +0100 [thread overview]
Message-ID: <50FD2172.2020608@grandegger.com> (raw)
In-Reply-To: <20130121100701.GX1906@pengutronix.de>
On 01/21/2013 11:07 AM, Sascha Hauer wrote:
> On Mon, Jan 21, 2013 at 09:56:24AM +0100, Wolfgang Grandegger wrote:
>> On 01/21/2013 09:37 AM, Sascha Hauer wrote:
>>> There may be multiple phys on an mdio bus. This series adds support
>>> for this to the fec driver. I recently had a board which has a switch
>>> connected to the fec's mdio bus, so I had to pick the correct phy.
>>
>> Pick one PHY from a switch port? Well, does a PHY-less (or fixed-link)
>> configuration for a switch not make more sense?
>
> Yes, you're probably right.
>
>> Various ARM Ethernet
>> contoller drivers do not support it. I recently needed a hack for an
>> AT91 board.
>
> I wonder how we want to proceed. Should there be a devicetree property
> 'fixed-link' like done for fs_enet (and not recommended for new code,
> stated in the comment above of_phy_connect_fixed_link)?
Also the gianfar and ucc_geth drivers use this interface (via fixed
link phy). I tried to use it for the AT91 macb driver but stopped
quickly because the usage was not straight forward (too much code)...
even if the idea of using a fake fixed-link phy is not bad.
> Currently I have a property 'phy' in the fec binding which has a phandle
> to a phy provided by the fec's mdio bus, but this could equally well
But than the cable must be connected to the associated switch port.
> point to a fixed dummy phy:
>
> phy = &fixed-phy;
The link speed, full/half duplex and maybe some mroe parameter should
be configurable via device tree.
> Currently there seems to be no common convention for the devicetree how
> to handle such situations, or am I missing something?
That's also may impression. There seem to be a few more related hacks:
$ find . -name '*.c'| xargs grep -i "phy-less"
./ethernet/amd/au1000_eth.c: netdev_info(dev, "using PHY-less setup\n");
./ethernet/amd/au1000_eth.c: } else { /* PHY-less op, assume full-duplex */
./ethernet/ibm/emac/core.c: /* PHY-less configuration.
./ethernet/ibm/emac/core.c: /* PHY-less configuration.
I would prefer to handle the "fixed-link" property of the ethernet dt
node directly in the driver with a generic helper function.
Wolfgang.
next prev parent reply other threads:[~2013-01-21 11:07 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-21 8:37 [PATCH] net: fec: Add support for multiple phys on mdiobus Sascha Hauer
2013-01-21 8:37 ` [PATCH 1/2] net: fec: refactor dt probing Sascha Hauer
2013-01-21 17:48 ` Baruch Siach
2013-01-21 18:27 ` Sascha Hauer
2013-01-21 8:37 ` [PATCH 2/2] net: fec: Add support for phys from devicetree Sascha Hauer
2013-01-21 8:56 ` [PATCH] net: fec: Add support for multiple phys on mdiobus Wolfgang Grandegger
2013-01-21 10:07 ` Sascha Hauer
2013-01-21 11:07 ` Wolfgang Grandegger [this message]
2013-01-21 11:12 ` Florian Fainelli
2013-01-21 11:33 ` Wolfgang Grandegger
2013-01-21 11:56 ` Sascha Hauer
2013-01-21 12:06 ` Sascha Hauer
2013-01-22 7:22 ` Wolfgang Grandegger
2013-01-22 14:47 ` Florian Fainelli
2013-01-22 15:03 ` Wolfgang Grandegger
2013-01-22 15:19 ` Florian Fainelli
2013-01-22 15:26 ` Wolfgang Grandegger
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