[U-Boot] [PATCH] mx28: fix i.MX28 spi driver

[Marek Vasut]

> On 1/14/12, Matthias Fuchs <matthias.fuchs at 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 at esd.eu>
> 
> Tested-by: Fabio Estevam <fabio.estevam at 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