tree 17f5dee33891f9b3aed3e10709a36d285c59b892
parent 1810f2c44817c74ca3d05d1e3981e3a2e2ceb6f5
author Alexander Shishkin <alexander.shishkin@linux.intel.com> 1455556326 +0200
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1456006154 -0800

stm class: Guard output assignment against concurrency

It is possible to concurrently assign the same output (a character
device writer or an stm_source device) to different stm devices,
which sets off a strategically placed warning in stm_output_assign().

To avoid this, use a spinlock to serialize (un)assignments between
outputs and stm devices.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>