Re: [PATCH 1/1] ALSA: usb: initial USB Audio Device Class 3.0 support

From: Takashi Iwai
Date: Sat Nov 11 2017 - 02:29:59 EST


On Sat, 11 Nov 2017 03:56:17 +0100,
Ruslan Bilovol wrote:
>
> On Thu, Nov 9, 2017 at 10:33 AM, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > On Thu, Nov 09, 2017 at 09:16:52AM +0100, Takashi Iwai wrote:
> >> On Thu, 09 Nov 2017 09:04:58 +0100,
> >> Greg Kroah-Hartman wrote:
> >> >
> >> > On Wed, Nov 08, 2017 at 03:38:35PM +0100, Takashi Iwai wrote:
> >> > > On Tue, 07 Nov 2017 03:01:20 +0100,
> >> > > Ruslan Bilovol wrote:
> >> > > >
> >> > > > Recently released USB Audio Class 3.0 specification
> >> > > > introduces many significant changes comparing to
> >> > > > previous versions, like
> >> > > > - new Power Domains, support for LPM/L1
> >> > > > - new Cluster descriptor
> >> > > > - changed layout of all class-specific descriptors
> >> > > > - new High Capability descriptors
> >> > > > - New class-specific String descriptors
> >> > > > - new and removed units
> >> > > > - additional sources for interrupts
> >> > > > - removed Type II Audio Data Formats
> >> > > > - ... and many other things (check spec)
> >> > > >
> >> > > > It also provides backward compatibility through
> >> > > > multiple configurations, as well as requires
> >> > > > mandatory support for BADD (Basic Audio Device
> >> > > > Definition) on each ADC3.0 compliant device
> >> > > >
> >> > > > This patch adds initial support of UAC3 specification
> >> > > > that is enough for Generic I/O Profile (BAOF, BAIF)
> >> > > > device support from BADD document.
> >> > > >
> >> > > > Signed-off-by: Ruslan Bilovol <ruslan.bilovol@xxxxxxxxx>
> >> > >
> >> > > The patch looks good, but the timing is fairly late for merging to
> >> > > 4.15.
> >> >
> >> > Isn't kbuild barfing all over these? Is that because of the cross-tree
> >> > changes needed?
> >>
> >> No, it's just local to the audio driver, plus a few
> >> include/linux/usb/*.h modification / addition.
> >> So there shouldn't be a big breakage in that regard.
>
> The UAC3 gadget driver (which I sent to linux-usb mailing list) depends on
> a new audio-v3.h header which is a part of this patch.
>
> So Felipe's tree will have dependency on Takashi's tree; and that's why
> kbuild notifies about build failure of UAC3 gadget driver.

OK, I see. I can prepare an immutable branch once when the patches
are ready to merge.


Takashi