On Fri, Oct 21, 2016 at 06:11:01PM +0530, Hardik Shah wrote:
This patch adds following documentation: 1. Bus driver locking mechanism. 2. Bus driver error handling.
Signed-off-by: Hardik Shah hardik.t.shah@intel.com Signed-off-by: Sanyog Kale sanyog.r.kale@intel.com Reviewed-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
Documentation/sound/alsa/sdw/error_handling.txt | 71 +++++++++++++++++++++++ Documentation/sound/alsa/sdw/locking.txt | 64 ++++++++++++++++++++ 2 files changed, 135 insertions(+) create mode 100644 Documentation/sound/alsa/sdw/error_handling.txt create mode 100644 Documentation/sound/alsa/sdw/locking.txt
diff --git a/Documentation/sound/alsa/sdw/error_handling.txt b/Documentation/sound/alsa/sdw/error_handling.txt new file mode 100644 index 0000000..9441cfa --- /dev/null +++ b/Documentation/sound/alsa/sdw/error_handling.txt @@ -0,0 +1,71 @@
<snip>
diff --git a/Documentation/sound/alsa/sdw/locking.txt b/Documentation/sound/alsa/sdw/locking.txt new file mode 100644 index 0000000..650162f --- /dev/null +++ b/Documentation/sound/alsa/sdw/locking.txt @@ -0,0 +1,64 @@ +This document explains locking mechanism of the SoundWire bus driver. +Following types of lock are used in SoundWire bus driver.
+1. Core lock +2. Master lock +3. Stream lock +4. Message lock
+1. Core lock: Global SoundWire bus driver lock. Core lock is used to +serialize each of the following operation(s) within SoundWire bus +driver.
- Addition and removal of Master.
- Acquire "Master lock" of each Master associated with the
aggregated stream.+2. Master lock: SoundWire bus instance lock. Master lock is used to +serialize each of the following operation(s) within SoundWire bus +instance.
- Addition and removal of Slave(s).
- Prepare and enable, disable and de-prepare.
+3. Stream lock: SoundWire stream lock. Stream lock is used to serialize +access of stream data structure for a SoundWire stream.
+4. Message lock: SoundWire message transfer lock. This lock is used to +serialize the message transfers(read/write) within the SoundWire bus +instance.
+Lock Hierarchy +==============
+- Core lock is the parent of Master and Stream lock. +- Master lock is parent of Message lock. +- Master and Stream locks are independent of each other.
A small diagram might be nice here, just would make it easier to see the hierarchy at a glance.
Thanks, Charles