From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH 2/2 V3] MXS: Implement DMA support into mxs-i2c Date: Mon, 16 Jul 2012 12:21:51 +0200 Message-ID: <20120716102151.GC17435@pengutronix.de> References: <1341850974-11977-1-git-send-email-marex@denx.de> <201207131410.29469.marex@denx.de> <20120714112929.GB29529@pengutronix.de> <201207141409.38554.marex@denx.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="E13BgyNx05feLLmH" Return-path: Content-Disposition: inline In-Reply-To: <201207141409.38554.marex-ynQEQJNshbs@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Marek Vasut Cc: Shawn Guo , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Detlev Zundel , Dong Aisheng , Fabio Estevam , Linux ARM kernel , Sascha Hauer , Stefano Babic , Uwe =?iso-8859-15?Q?Kleine-K=F6nig?= , Wolfgang Denk List-Id: linux-i2c@vger.kernel.org --E13BgyNx05feLLmH Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Marek, > > I am also still interested to check the runtime switching, but it might > > take another month until I can really hack on it. >=20 > Good, there is some bit that probably needs to be flipped to allow this= =20 > switching. I managed to get this working with SPI, not with i2c though. W= ith=20 Ah, hearing that it works with SPI is good news. > i2c, if I restarted the controller inbetween each transaction, it worked = =2E..=20 > 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. > >=20 > > 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. >=20 > But then, how would you configure this detail on a per-bus basis? Well al= l=20 This is a question for devicetree-discuss. > patch actually fixes a real issue, I'd like to have it in ASAP and it's b= een=20 > 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 --=20 Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | --E13BgyNx05feLLmH Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlAD6z8ACgkQD27XaX1/VRtrugCZAeJ0OseVZMeJHaXAW/iUDhV6 Y0MAoIKNisitB76lIucWMoblPrC9UYn8 =mTPu -----END PGP SIGNATURE----- --E13BgyNx05feLLmH--