[PATCH 3/4] spi: bcm2835aux: set up spi-mode before asserting cs-gpio

Mark Brown broonie at kernel.org
Thu Feb 11 04:27:36 PST 2016

On Wed, Feb 10, 2016 at 09:26:05PM +0100, Stephan Olbrich wrote:
> Am Wednesday 10 February 2016, 19:02:04 schrieb Mark Brown:

> > No guarantee that they'll not change, especially in a situation where we
> > have two devices on different speeds on a bus working at the same time.

> Are you saying, that between a prepare and unprepare there could be transfers 
> for another device? Then all the clock setting couldn't be done in prepare 
> either.
> Apart from that, if two transfers in the same message are not guarantied to 
> have the same speed, this still needs to be fixed. I'll roll a v2.

There are two prepares, I don't know which you're talking about.  The
most common is prepare_transfer_hardware() which is used to power up the
hardware and may have many transfers for many devices before it is
reversed.  The other is prepare_message() which is called once per
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