From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eddie James Subject: Re: [PATCH v11 5/8] i2c: fsi: Add transfer implementation Date: Tue, 10 Jul 2018 12:52:58 -0500 Message-ID: References: <1530816030-13010-1-git-send-email-eajames@linux.vnet.ibm.com> <1530816030-13010-6-git-send-email-eajames@linux.vnet.ibm.com> <20180709224114.4h47enyt4tucqcou@ninjato> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180709224114.4h47enyt4tucqcou@ninjato> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Wolfram Sang Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, robh+dt@kernel.org, benh@kernel.crashing.org, joel@jms.id.au, mark.rutland@arm.com, gregkh@linuxfoundation.org, rdunlap@infradead.org, andy.shevchenko@gmail.com, peda@axentia.se List-Id: linux-i2c@vger.kernel.org On 07/09/2018 05:41 PM, Wolfram Sang wrote: >> + cmd |= FIELD_PREP(I2C_CMD_ADDR, msg->addr >> 1); > I just noticed this and wonder: Don't you need the LSB of the address? > It is not the RW flag, this is encoded in msg->flags. So, the hardware interprets the LSB as the RW flag. It wouldn't be possible to have a device addressed with the LSB set on this I2C master. > > Also, no seperate handling for 10 bit addresses? Technically, 7-bit 0x50 > is different on the wire from 10-bit 0x050. This is minor, though. There > are no 10-bit devices out there. Still, did you test 10-bit support? Indeed, real 10-bit addresses require some additional manipulation of this I2C master in order to work. We don't support it right now. Thanks, Eddie > > Rest looks good. >