Jeff Garzik posted a two patch series introducing an asynchronous event notification infrastructure, "enabling SATA Asynchronous Notification ('AN') for CD/DVD devices that support it." He summarized:
"For devices that support SATA AN (only very recent ones do), this means that HAL and other userspace utilities no longer need to repeatedly poll the CD/DVD device to determine if the user has changed the media."
The first patch is for the SCSI driver and is based on work originally done by Kristen Carlson Accardi, along with "copious input from James Bottomley". The second patch updates libata to utilize the new SCSI event infrastructure.
From: Jeff Garzik <jeff@...>
Subject: [PATCH v4 0/2] [SCSI] Asynchronous event notification infrastructure
Date: Oct 29, 10:42 am 2007
This is the next revision of the SCSI event notification infrastructure
patchset, enabling SATA Asynchronous Notification ("AN") for CD/DVD
devices that support it.
For devices that support SATA AN (only very recent ones do), this means
that HAL and other userspace utilities no longer need to repeatedly poll
the CD/DVD device to determine if the user has changed the media.
This revision takes into account James' comments from earlier today,
modulo the following notes:
* I think the various event attributes should always be present,
for all devices at all times. If various events are not supported,
the attribute will of course return zero (false, not supported).
* I do not think this work should be blocked behind a revamp
of the attribute group interface.
* I was slack and did not bother to implement the 'set' operation
for the attributes. This can easily be done at a later time in a
separate patch. It is not a merge stopper to have the driver
exclusively control the event mask, rather than driver+sysfs.
-
