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From: Marek Vasut <marek.vasut@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH V3+] I2C: mxc_i2c rework
Date: Wed, 14 Sep 2011 21:39:29 +0200	[thread overview]
Message-ID: <201109142139.29539.marek.vasut@gmail.com> (raw)
In-Reply-To: <CAFQ4atTS=ptKnNe_ntfA-ypV5Ctw+AeudHG5=pJYYNmju+f-EA@mail.gmail.com>

On Friday, July 29, 2011 08:55:14 AM Jason Hui wrote:
> Hi, Marek,
> 
> On Thu, Jul 14, 2011 at 5:58 AM, Marek Vasut <marek.vasut@gmail.com> wrote:
> > Rewrite the mxc_i2c driver.
> >  * This version is much closer to Linux implementation.
> >  * Fixes IPG_PERCLK being incorrectly used as clock source
> >  * Fixes behaviour of the driver on iMX51
> >  * Clean up coding style a bit ;-)
> 
> why you change i2c clock from IPG_PERCLK to IPG_CLK?
> 
> [...]

Ok, I investigated a bit deeper and I suspect the clock.c is the culprit.

Apparently, the PERCLK doesn't run at the frequency the clock.c reports it runs 
on. Therefore, the i2c miscalculates the divider etc -- falling crap model 
(waterfall model).

Anyway, Jason, can you look into that clock problem? I think there are more than 
just perclk miscalculated.

Cheers

  parent reply	other threads:[~2011-09-14 19:39 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-13 21:58 [U-Boot] [PATCH V3+] I2C: mxc_i2c rework Marek Vasut
2011-07-14  9:04 ` Heiko Schocher
2011-07-28 14:29   ` Wolfgang Denk
2011-07-14 13:55 ` Albert ARIBAUD
2011-07-14 14:35   ` Marek Vasut
2011-07-14 14:45     ` Albert ARIBAUD
2011-07-29  6:55 ` Jason Hui
2011-07-29  9:35   ` Marek Vasut
2011-07-29  9:42     ` Stefano Babic
2011-09-14 19:39   ` Marek Vasut [this message]
2011-09-15  1:43     ` Jason Hui
2011-09-15  2:07       ` Marek Vasut
2011-09-15  2:26         ` Jason Hui
2011-09-15  4:07           ` Marek Vasut
2011-08-30 10:48 ` Stefano Babic
  -- strict thread matches above, loose matches on Subject: below --
2011-07-13 21:05 [U-Boot] [PATCH V3] " Marek Vasut
2011-07-13 21:34 ` Wolfgang Denk

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