[PATCH v2 0/3] firewire: assist unit driver to compute packet time stamp

Takashi Sakamoto o-takashi at sakamocchi.jp
Sat Feb 12 03:21:28 CET 2022


Hi,

Current implementation of Linux FireWire subsystem doesn't allow unit
driver to operate content of packet in IR context according to
time stamp. Additionally it doesn't allow unit driver to read current value
of CYCLE_TIME register in OHCI 1394 controller. It brings disadvantages to
drivers in Linux sound subsystem in regards of handling time for sampled
data such as PCM frames and MIDI messages.

This rerolled patchset is first step to improve the situation.

Changes in v2:
 * Rebase v1 patchset to v5.16 release

V1:
 * https://lore.kernel.org/lkml/20211202113457.24011-1-o-takashi@sakamocchi.jp/


Hector Martin (1):
  firewire: Add dummy read_csr/write_csr functions

Takashi Sakamoto (2):
  firewire: add kernel API to access CYCLE_TIME register
  firewire: add kernel API to access packet structure in request
    structure for AR context

 drivers/firewire/core-card.c        | 39 +++++++++++++++++++++++++++++
 drivers/firewire/core-cdev.c        |  6 +++--
 drivers/firewire/core-transaction.c | 18 +++++++++++++
 include/linux/firewire.h            |  3 +++
 4 files changed, 64 insertions(+), 2 deletions(-)

-- 
2.32.0



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