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 for linux-mtd@lists.infradead.org; Thu, 17 Apr 2014 15:45:52 +0000
From: Marek Vasut <marex@denx.de>
To: Huang Shijie <shijie8@gmail.com>
Subject: Re: [PATCH] mtd: spi-nor: fix the wrong dummy value
Date: Thu, 17 Apr 2014 16:15:24 +0200
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Cc: Huang Shijie <b32955@freescale.com>, computersforpeace@gmail.com,
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On Thursday, April 17, 2014 at 02:59:21 PM, Huang Shijie wrote:
> On Thu, Apr 17, 2014 at 01:32:52PM +0200, Marek Vasut wrote:
> > On Thursday, April 17, 2014 at 07:01:25 AM, Huang Shijie wrote:
> > > On Thu, Apr 17, 2014 at 01:40:29AM +0200, Marek Vasut wrote:
> > > > On Wednesday, April 16, 2014 at 10:18:19 AM, Huang Shijie wrote:
> > > > > The dummy cycles is actually 8 for SPI fast/dual/quad read.
> > > > > 
> > > > > This patch fixes the wrong dummy value for both the spi-nor.c and
> > > > > m25p80.c.
> > > > > 
> > > > > Signed-off-by: Huang Shijie <b32955@freescale.com>
> > > > 
> > > > Inspecting this patch, I see the code will behave identically
> > > > with/without this patch. It is thus unclear to me from the commit
> > > > message, why this change is necessary.
> > > 
> > > firstly, in theory, the dummy cycles should be 8, not 1.
> > > secondly, the DDR QUAD READ may use 4 dummy cycles.
> > 
> > Right, it took me a bit of reading into the thread until I understood the
> > intention of the patch. If in doubt, try reading the commit message a day
> > later and you'll see that it might be insufficient. Basically, try
> > looking at the commit message from the receiving party's side ;-)
> 
> my fault.
> 
> I will update the commit message in the next version.

Thanks!

Best regards,
Marek Vasut