On Wed, Sep 11, 2013 at 03:05:15PM +0100, David Woodhouse wrote:

Why can't the flash driver *provide* the required information?

Yeah, that's my question too...

So far I seem to have got it into my head that we have a SPI controller
which is connected to more than one device, and we can't send commands
to one without sending to the other... and that means that we have to
send a *NOP* to the "unwanted" device. Is that right?

That shouldn't be the case, SPI has a chip select line which is asserted
to talk to a particular chip, while it's not asserted the slaves should
ignore any activity on the bus.  If activity on one slave affects
another something is broken, this is the first time I noticed that being
an issue but I might've missed some of the MTD side of this thread.
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