From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH 2/2 V3] MXS: Implement DMA support into mxs-i2c Date: Mon, 16 Jul 2012 15:06:07 +0200 Message-ID: <201207161506.08147.marex@denx.de> References: <1341850974-11977-1-git-send-email-marex@denx.de> <201207141409.38554.marex@denx.de> <20120716102151.GC17435@pengutronix.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120716102151.GC17435-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wolfram Sang Cc: Shawn Guo , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Detlev Zundel , Dong Aisheng , Fabio Estevam , Linux ARM kernel , Sascha Hauer , Stefano Babic , Uwe =?iso-8859-1?q?Kleine-K=F6nig?= , Wolfgang Denk List-Id: linux-i2c@vger.kernel.org Dear Wolfram Sang, > Marek, > > > > I am also still interested to check the runtime switching, but it might > > > take another month until I can really hack on it. > > > > Good, there is some bit that probably needs to be flipped to allow this > > switching. I managed to get this working with SPI, not with i2c though. > > With > > Ah, hearing that it works with SPI is good news. > > > i2c, if I restarted the controller inbetween each transaction, it worked > > ... which is not what I'd like to see there. > > Agreed. > > > > > No, it doesn't. See above about small transfers. Consider the easy > > > > situation where you have sensor on one bus (so you do PIO because you > > > > transfer small data) and you have EEPROM on other bus, where you use > > > > DMA because you transfer large data. And the mixed mode isn't there > > > > yet. > > > > > > I fully understand what you want to configure. I did before. Yet, > > > devicetree bindings are not platform_data and shouldn't be used like > > > them. > > > > But then, how would you configure this detail on a per-bus basis? Well > > all > > This is a question for devicetree-discuss. Did you Cc it? > > patch actually fixes a real issue, I'd like to have it in ASAP and it's > > been aboue three months already, which sucks. > > I am open to ideas improving the situation (which is: a lot more > patches, but not a lot more reviewers) > > Thanks, > > Wolfram Best regards, Marek Vasut