On 8/29/20 5:51 PM, Jonathan Cameron wrote:
On Wed, 26 Aug 2020 09:36:39 +0300
Alexandru Ardelean <ardeleanalex@xxxxxxxxx> wrote:
On Wed, Aug 26, 2020 at 8:22 AM Lars-Peter Clausen <lars@xxxxxxxxxx> wrote:
From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
A transfer may fall shorter than the bytes in the block.
This information is available in the residue from the DMA engine, so we can
compute actual `bytes_used` with that by subtracting the residue.
This was in my pipeline as well [obviously].
Thanks :)
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
"smells" like a fix. Is it? Or are we looking at something that
only matters for some future hardware, or an optmization?
If it's a fix, where is the fixes tag?
It's a feature :)
When we first added the IIO DMA buffer support this API did not exist in
dmaengine. So for the longest time most DMA drivers did not have the
ability to report short transfers. Primarily because in many cases the
hardware doesn't even support it.
Now with this patch the IIO DMA buffer implementation supports systems
where the DMA can generate short transfers.
- Lars
