Re: [PATCH v3 0/3] firewire: assist unit driver to compute packet time stamp

From: Takashi Iwai
Date: Thu Apr 07 2022 - 02:02:21 EST


On Thu, 07 Apr 2022 02:10:21 +0200,
Takashi Sakamoto wrote:
>
> On Tue, Apr 05, 2022 at 06:23:35PM +0200, Takashi Iwai wrote:
> > On Tue, 05 Apr 2022 09:22:18 +0200,
> > Takashi Sakamoto wrote:
> > >
> > > 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 v3:
> > > * Rebase v2 patchset to v5.18-rc1
> > > Changes in v2:
> > > * Rebase v1 patchset to v5.16 release
> > > * https://lore.kernel.org/lkml/20220212022131.199855-1-o-takashi@xxxxxxxxxxxxx/
> > > V1:
> > > * https://lore.kernel.org/lkml/20211202113457.24011-1-o-takashi@xxxxxxxxxxxxx/
> > >
> > > 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
> >
> > Thanks, applied all three patches now to for-next branch.
>
> Although thanks for your applying them into your tree, I apologize to
> trouble you if you overlook that the included changes is just for Linux
> FireWire subsystem. It's my fault to send them only to Linux sound
> subsystem, but the changes are required to my work in sound drivers...
>
> If you are willing to include patches to Linux FireWire subsystem for
> your pull-request to Linus, I can prepare respined patches for it since
> I have the list of patches posted to LKML as bug fixes for Linux FireWire
> subsystem.
>
> I need any help to solve current situation of Linux FireWire subsystem
> that bug fixes and new changes are hardly merged. Of course, IEEE 1394 bus
> is already outdated and legacy, but I know that some users still work
> with it. If your path is available for it, it's the easiest and the most
> convenient way for upstreaming, I think.

Ah OK, it's fine for me in either way. I can keep up those changes in
my tree, or go through others. I leave the decision Firewire
subsystem people. Just let me know.


thanks,

Takashi