From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: Applied "spi: Add Renesas R-Car Gen3 RPC-IF SPI controller driver" to the spi tree Date: Wed, 13 Feb 2019 13:37:31 +0100 Message-ID: References: <20190212142236.2807D1128113@debutante.sirena.org.uk> <4f91497a-96ee-4c10-436f-4d011edb3834@gmail.com> <20190212144359.GD20635@sirena.org.uk> <20190212164940.GI20635@sirena.org.uk> <20190213121635.GD7540@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: bbrezillon@kernel.org, Geert Uytterhoeven , Simon Horman , juliensu@mxic.com.tw, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-spi@vger.kernel.org, Sergei Shtylyov , zhengxunli@mxic.com.tw To: Mark Brown , masonccyang@mxic.com.tw Return-path: In-Reply-To: <20190213121635.GD7540@sirena.org.uk> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org On 2/13/19 1:16 PM, Mark Brown wrote: > On Wed, Feb 13, 2019 at 04:25:32PM +0800, masonccyang@mxic.com.tw wrote: > >> From current mainline branch, MFD seems support the device which is on >> the same hardware bus(i.e, I2C, SPI, MMIO and SPMI)for multi-function >> by Read/Write the common same registers. > > That's most MFDs but there are some that do some level of enumeration > (even if it's just looking at the device ID that got registered) to > decide what subdevices get registered, that's what people are suggesting > here I think. Right. Although I think some of the code could be shared between the SPI and HF modes. >> I am checking and not sure if MMIO of MFD could support RPC-IF for >> different hardware bus on SPI and CFI. >> I also doubt if this method is a correct solution for RPC-IF works >> either in SPI mode or CFI mode. > > For MMIO devices MFD just passes through the parent resources. > -- Best regards, Marek Vasut