From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Subject: Re: [PATCH] i2c: algo-bit: add support for I2C_M_STOP Date: Thu, 22 Jun 2017 11:06:06 +0200 Message-ID: <20170622110606.6ae3aabc@endymion> References: <20170617171238.19638-1-wsa+renesas@sang-engineering.com> <20170619103002.5d502c92@endymion> <20170620172810.h2anac45n5u3oova@ninjato> <20170621091843.657de813@endymion> <20170621143018.GA1571@katana> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170621143018.GA1571@katana> Sender: linux-renesas-soc-owner@vger.kernel.org To: Wolfram Sang Cc: Wolfram Sang , linux-i2c@vger.kernel.org, linux-renesas-soc@vger.kernel.org List-Id: linux-i2c@vger.kernel.org On Wed, 21 Jun 2017 16:30:18 +0200, Wolfram Sang wrote: > Which reminds me: Have you ever seen a 10-bit client device in the wild? > I wanted to buy one for testing reasons but was not able to locate one. > I only know a Renesas IP core which has 10-bit slave capability (but no > driver support for that yet). I remember wishing I could drop support, asking around, and a few people replying to me that 10-bit slaves actually exist. But of course I can't find the discussion thread again. I can see one driver for a 10-bit address I2C device: drivers/media/i2c/tw2804.c (device instantiated from drivers/media/usb/go7007/go7007-usb.c.) However it seems that in many cases I2C_M_TEN is used directly (instead of the more correct I2C_CLIENT_TEN.) See for example drivers/input/touchscreen/atmel_mxt_ts.c, drivers/input/touchscreen/elants_i2c.c, drivers/input/touchscreen/mms114.c, drivers/media/pci/cx23885/cx23885-i2c.c, drivers/media/pci/cx25821/cx25821-i2c.c, which are clearly talking to 10-bit I2C devices, but without instantiating an i2c_client for them. I see also commits explicitly adding or fixing 10-bit address support in various I2C bus drivers, I don't think developers would be doing that if they didn't need it. -- Jean Delvare SUSE L3 Support