Re: [patch V2 5/6] edma: Make reading the position of active channels work

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On 04/28/2014 05:49 AM, Thomas Gleixner wrote:
> As Joel pointed out, edma_read_position() uses memcpy_fromio() to read
> the parameter ram. That's not synchronized with the internal update as
> it does a byte by byte copy. We need to do a 32bit read to get a
> consistent value.
> 
> Further reading destination and source is pointless. In DEV_TO_MEM
> transfers we are only interested in the destination, in MEM_TO_DEV we
> care about the source. In MEM_TO_MEM it really does not matter which
> one you read.
> 
> Simple solution: Remove the pointers, select dest/source via a bool
> and return the read value.
> 
> Remove the export of this function while at it. The only potential
> user is the dmaengine and that's always builtin.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Thanks, this looks good.

Acked-by: Joel Fernandes <joelf@xxxxxx>


Regards,
-Joel

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