[PATCH v2 1/3] spi: implemented driver for Cirrus EP93xx SPI controller

Martin Guy martinwguy at gmail.com
Wed Mar 31 20:15:20 EDT 2010

On 3/25/10, Mika Westerberg <mika.westerberg at iki.fi> wrote:
>  > > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>  > >  in EP93xx chips (EP9301, EP9302, EP9307, EP9312 and EP9315).
>  > >
>  > >  Driver currently supports only interrupt driven mode but in future we may add
>  > >  polling mode support as well.

I've been staring more at this again and it looks (2 clock
strangenesses and extensive control reg setting apart) like good code.
I have another question: like the Cirrus driver, this takes 100% CPU
doing busy wait for the current transfer to complete.
Given that this driver is interrupt-based, is there any reason why it
can't do something else in the meanwhile?
Not that that's a reason not to include it in 2.6.35 - it works well
and we can think whether to make it more efficient in N+1...


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