[PATCH] i2c: mxs: remove broken PIOQUEUE support
Marek Vasut
marex at denx.de
Thu Nov 1 10:28:17 EDT 2012
Dear Wolfram Sang,
> This I2C master can do DMA and PIOQUEUE (PIO with FIFO). Originally,
> only PIOQEUE
PIOQUEUE ;-)
> was supported, then DMA support was added. The original
> intention was to keep PIOQUEUE since it has less overhead what is nice
> for small transfers. However, runtime switching between PIOQEUE and DMA
> depending on the transfer size never worked despite a lot of trying.
> Since PIOQUEUE mode itself was flaky (polling at places where interrupts
> failed to work) and the implementation also imposed a size limit for
> transfers, it is best to remove the support altogether which makes the
> driver a lot cleaner and more robust. If somebody really wants less
> overhead, plain PIO mode could still be implemented with the addidtional
> advantage that this mode is also available on MX23, too.
Yes, looks to be the way to go.
Reviewed-by: Marek Vasut <marex at denx.de>
Thanks
[...]
Best regards,
Marek Vasut
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