From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marek.vasut@gmail.com>
Date: Mon, 23 Jan 2012 20:53:10 +0100
Subject: [U-Boot] [PATCH] mx28: fix i.MX28 spi driver
In-Reply-To: <CAOMZO5D2z+cAEcUG60J-h+gwbYtL8EVu1Qu3Q_mDc-pp=GOCgA@mail.gmail.com>
References: <4F117435.7080807@esd.eu>
	<CAOMZO5D2z+cAEcUG60J-h+gwbYtL8EVu1Qu3Q_mDc-pp=GOCgA@mail.gmail.com>
Message-ID: <201201232053.10581.marek.vasut@gmail.com>
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> On 1/14/12, Matthias Fuchs <matthias.fuchs@esd.eu> wrote:
> > The generic spi flash driver (drivers/mtd/spi/spi_flash.c) uses the
> > spi low level driver's spi_xfer() function with len=0 to deassert the
> > SPI flash' chip select. But the i.MX28 spi driver rejects this call
> > due to len=0.
> > 
> > This patch implements an exception for len=0 with the SPI_XFER_END
> > flag set. This results in an extra read with the chip select being
> > deasserted afterwards. There seems to be no way to deassert the signal
> > by hand.
> > 
> > Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
> 
> Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
> 
> Soldered a SST25VF016B on a mx28evk (and also the SPI pullups) and
> verified that the flash can be erased succesfully now.
> 
> I suggest that this patch gets applied as it fixes a real issue.
> 
> Thanks,
> 
> Fabio Estevam

I'm all for it.

M