firewire: cdev: implement new event to notify request subaction with time stamp
authorTakashi Sakamoto <o-takashi@sakamocchi.jp>
Mon, 29 May 2023 23:12:40 +0000 (08:12 +0900)
committerTakashi Sakamoto <o-takashi@sakamocchi.jp>
Mon, 29 May 2023 23:12:40 +0000 (08:12 +0900)
commit865efffb2d11402bc6f96c7e390b89384e9d209d
tree8964e7f150f3883bb5c2349ed41c12de68fc695a
parent7c22d4a92bb26f2357b27446138c8be54f88caed
firewire: cdev: implement new event to notify request subaction with time stamp

In 1394 OHCI, the trailer quadlet of descriptor in Asynchronous Receive
(AR) request context has timeStamp field, in which the 1394 OHCI
controller record the isochronous cycle when the packet arrived.

Current implementation of 1394 OHCI controller driver stores the value
of field to internal structure as time stamp, while the implementation
of FireWire character device doesn't have a field for the time stamp,
thus it is not available in user space. The time stamp is convenient to
some kind of application in which data from several sources are compared
in isochronous cycle unit.

This commit implement the new event, fw_cdev_event_request3, with an
additional field, tstamp.

Link: https://lore.kernel.org/r/20230529113406.986289-5-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
drivers/firewire/core-cdev.c