From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH v2 2/6] net: phy: broadcom: Add BCM54810 PHY entry Date: Tue, 1 Nov 2016 17:26:48 +0100 Message-ID: <20161101162648.GG10785@lunn.ch> References: <1477688219-3871-1-git-send-email-jon.mason@broadcom.com> <1477688219-3871-3-git-send-email-jon.mason@broadcom.com> <20161029081839.GA32579@lunn.ch> <20161101155950.GA19378@broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20161101155950.GA19378@broadcom.com> Sender: linux-kernel-owner@vger.kernel.org To: Jon Mason Cc: David Miller , Rob Herring , Mark Rutland , Florian Fainelli , devicetree@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, rafal@milecki.pl, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org > > > + if (of_property_read_bool(np, "brcm,enet-phy-lane-swap")) { > > > + /* Lane Swap - Undocumented register...magic! */ > > > + ret = bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_SEL_ER + 0x9, > > > + 0x11B); > > > + if (ret < 0) > > > + return ret; > > > + } > > > + > > > > I wounder if this property could be made generic? What exactly are you > > swapping? Rx and Tx lanes? Maybe we should add it to phy.txt? > > Are you envisioning adding a DT check (similar to the > of_property_read_bool above, only with a more generic string) in > phy_device_create(), which will then set a PHY device flag? This flag > would then be checked for in the PHY driver and the appropriate action > taken (in this case the bcm_phy_write_exp above). I would keep the parsing of the property in the driver. But if we think other PHYs could also support this feature, it would be good to avoid having "brcm,enet-phy-lane-swap", "marvell,enet-phy-lane-swap", "davicom,enet-phy-lane-swap", etc. It would be better to have one well defined property documented in phy.txt which any PHY is free to implement. Andrew