tree b526b348ed1b64884bf672924540bb5dc29cb211
parent 9c402f4e196290692d998b188f9094deb1619e57
author Dan Williams <dan.j.williams@intel.com> 1215543501 -0700
committer Dan Williams <dan.j.williams@intel.com> 1215543501 -0700

dmaengine: track the number of clients using a channel

Haavard's dma-slave interface would like to test for exclusive access to a
channel.  The standard channel refcounting is not sufficient in that it
tracks more than just client references, it is also inaccurate as reference
counts are percpu until the channel is removed.

This change also enables a future fix to deallocate resources when a client
declines to use a capable channel.

Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>