On Sun, Apr 06, 2014 at 12:26:55PM +0100, Russell King - ARM Linux wrote: > Ergh. So much for "DT describes the hardware, not the software > implementation." > > commit 954c396756e3d31985f7bc6a414a988a4736a7d0 > Author: Sean Cross <xobs@xxxxxxxxxx> > Date: Wed Aug 21 01:46:12 2013 +0000 > > net/phy: micrel: Add OF configuration support for ksz9021 > > Some boards require custom PHY configuration, for example due to trace > length differences. Add the ability to configure these registers in > order to get the PHY to function on boards that need it. > > Because PHYs are auto-detected based on MDIO device IDs, allow PHY > configuration to be specified in the parent Ethernet device node if no > PHY device node is present. > > If we were describing the hardware, we'd create a node for the phy and put > the phy specific properties in there, and reference it from the ethernet > driver, and have some way to look up the phy node when we automatically > discover the phy. This is exactly how new style devices work, like allwinner case below. arch/arm/boot/dts/sun4i-a10-a1000.dts drivers/net/ethernet/allwinner/sun4i-emac.c > > Well, it's too late to do anything else now, we're stuck with this, and > I guess everyone's going to be stuffing the phy chip's configuration into > the ethernet device's node from now on. :( Let's take a look at ksz9021_config_init(). if (!of_node && dev->parent->of_node) of_node = dev->parent->of_node; It's a stepping back in case that the phy device has no of_node attached. So for phy devices that are initiated from device tree like allwinner case above, they will just work in the sane way. Shawn -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
