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SubjectRe: mc13xxx-core: kernel hangs after 'regmap_read'
On Thu, May 24, 2012 at 1:41 PM, Uwe Kleine-König
<> wrote:

>> If this is actually the issue the usual fix for this if the SPI
>> controller hardware can't be persuaded to do the right thing is to put
>> the chip select pin in GPIO mode and manage it by hand, though looking
>> at the driver it appears it should be doingn that already.  If you
>> change to using the bitbanging SPI driver it should do the right thing
>> (but will obviously be hideously slow), that ought to be at least a good
>> reference for expected behaviour here.
> The imx spi driver can do both (GPIO and hardware CS) because not all
> pins that can do hardware CS are available as GPIO.

Right, unfortunately on mx31 the SPI CS pins cannot be used as GPIOs.

On mx51evk the SPI CS are used as GPIOs and that probably explains why
it worked on mx51evk and fails on mx31pdk.
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