From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH v4 04/14] net: phy: adin: add {write,read}_mmd hooks Date: Mon, 12 Aug 2019 16:06:48 +0200 Message-ID: <20190812140648.GN14290@lunn.ch> References: <20190812112350.15242-1-alexandru.ardelean@analog.com> <20190812112350.15242-5-alexandru.ardelean@analog.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190812112350.15242-5-alexandru.ardelean@analog.com> Sender: linux-kernel-owner@vger.kernel.org To: Alexandru Ardelean Cc: netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, davem@davemloft.net, robh+dt@kernel.org, mark.rutland@arm.com, f.fainelli@gmail.com, hkallweit1@gmail.com List-Id: devicetree@vger.kernel.org On Mon, Aug 12, 2019 at 02:23:40PM +0300, Alexandru Ardelean wrote: > Both ADIN1200 & ADIN1300 support Clause 45 access for some registers. > The Extended Management Interface (EMI) registers are accessible via both > Clause 45 (at register MDIO_MMD_VEND1) and using Clause 22. > > The Clause 22 access for MMD regs differs from the standard one defined by > 802.3. The ADIN PHYs use registers ExtRegPtr (0x0010) and ExtRegData > (0x0011) to access Clause 45 & EMI registers. > > The indirect access is done via the following mechanism (for both R/W): > 1. Write the address of the register in the ExtRegPtr > 2. Read/write the value of the register via reg ExtRegData > > This mechanism is needed to manage configuration of chip settings and to > access EEE registers via Clause 22. > > Since Clause 45 access will likely never be used, it is not implemented via > this hook. > > Signed-off-by: Alexandru Ardelean Reviewed-by: Andrew Lunn Andrew