Re: [PATCH 0/2] firewire: core: allow unit drivers to schedule work item to process isochronous context

[Takashi Sakamoto <o-takashi@sakamocchi.jp>]

On Sun, Sep 08, 2024 at 01:05:47PM +0900, Takashi Sakamoto wrote:
> Hi,
> 
> ALSA firewire stack uses packet-per-buffer mode for both isochronous
> receive (IR) and transmit (IT) contexts of 1394 OHCI. To process time
> stamp per packet (or per sample in some cases) steadily for media clock
> recovery against unexpected transmission skips in the IR context, it uses
> an IT context to operate all of isochronous contexts by calls of
> fw_iso_context_flush_completions() in the bottom-half of hardIRQ for the
> IT context.
> 
> Although it looks well to handle all of isochronous contexts in a single
> bottom-half context, it relatively takes longer time to finish. In the
> future code integration (not yet), it is possible to apply parallelism
> method to process these context. In the case, it is useful to allow unit
> drivers to schedule work items to process these isochronous contexts.
> 
> As a preparation, in this series of changes,
> fw_iso_context_schedule_flush_completions() is exposed as a kernel API
> available by unit drivers. It is a counter part of
> fw_iso_context_flush_completions(). This series of changes also includes
> documentation about these kernel APIs.
> 
> Takashi Sakamoto (2):
>   firewire: core: expose kernel API to schedule work item to process
>     isochronous context
>   firewire: core: fulfill documentation of
>     fw_iso_context_flush_completions()
> 
>  Documentation/driver-api/firewire.rst |  2 ++
>  drivers/firewire/core-iso.c           | 11 +++++++++++
>  drivers/firewire/core.h               |  5 -----
>  drivers/firewire/ohci.c               |  4 ++--
>  include/linux/firewire.h              | 17 +++++++++++++++++
>  5 files changed, 32 insertions(+), 7 deletions(-)

Applied to for-next branch.


Regards

Takashi Sakamoto