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From: Wolfram Sang <w.sang-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
To: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	Fabio Estevam <festevam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	Shawn Guo <shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>,
	linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: possible MXS-i2c bug
Date: Fri, 27 Apr 2012 16:59:36 +0200	[thread overview]
Message-ID: <20120427145936.GD16504@pengutronix.de> (raw)
In-Reply-To: <201204270110.21377.marex-ynQEQJNshbs@public.gmane.org>

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Hi,

> I've been thinking about the DMA approach. The problem I found out is that we 
> need to transfer all messages we're given at time in one DMA chain ... at least 
> that's how I understand it from the FSL manual (see Fig. 27-10 in the mx28 
> manual).

I can't follow you:  mxs_i2c_xfer() gets a list of messages, yet they
are iterated over in mxs_i2c_xfer_msg(). A single I2C message is
unscattered and can't be bigger than 64KB, so that should be doable?

Am I missing something by already being in weekend-mode? :)

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

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  parent reply	other threads:[~2012-04-27 14:59 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <201204261326.29388.marex@denx.de>
     [not found] ` <201204261326.29388.marex-ynQEQJNshbs@public.gmane.org>
2012-04-26 11:42   ` possible MXS-i2c bug Wolfram Sang
     [not found]     ` <20120426114201.GC3548-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2012-04-26 23:10       ` Marek Vasut
     [not found]         ` <201204270110.21377.marex-ynQEQJNshbs@public.gmane.org>
2012-04-27 14:59           ` Wolfram Sang [this message]
     [not found]             ` <20120427145936.GD16504-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2012-04-27 15:08               ` Marek Vasut
     [not found]                 ` <201204271708.53467.marex-ynQEQJNshbs@public.gmane.org>
2012-04-27 15:41                   ` Wolfram Sang
     [not found]                     ` <20120427154119.GF16504-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2012-04-27 15:53                       ` Marek Vasut
     [not found]                         ` <201204271753.39516.marex-ynQEQJNshbs@public.gmane.org>
2012-04-27 16:37                           ` Wolfram Sang
     [not found]                             ` <20120427163756.GH16504-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2012-04-28  3:03                               ` [TEST PATCH] mxs-i2c DMA support Marek Vasut

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