tree 0d16845eb5f9f7029a67934cc03af2e515f31696
parent 1581a03573e6c9ebd931e31f9172cce25dcb69e6
author Ian Abbott <abbotti@mev.co.uk> 1368191308 +0100
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1368481024 -0400

staging: comedi: allow buffer resize if previous resize failed

When a comedi device is successfully attached, those subdevices that
support asynchronous commands will have had buffers allocated
successfully.  It is possible to resize the buffers afterwards, but if
the resize fails the subdevice is left with no buffer
(`s->async->prealloc_buf == NULL`).  Currently, this also causes any
subsequent attempts to resize the buffer to fail with an error, which
seems like a bad idea.

Remove the check in `resize_async_buffer()` that causes the resize to
fail if the subdevice currently has no buffer (presumably due to the
failure of a previous resize attempt).  Callers of
`resize_async_buffer()` have already checked that the subdevice is
allowed to have a buffer.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>