Commit Graph

43 Commits

Author SHA1 Message Date
chihhao.chen
40d784cc39 ALSA: usb-audio: fix incorrect clock source setting
[ Upstream commit 4511781f95da0a3b2bad34f3f5e3967e80cd2d18 ]

The following scenario describes an echo test for
Samsung USBC Headset (AKG) with VID/PID (0x04e8/0xa051).

We first start a capture stream(USB IN transfer) in 96Khz/24bit/1ch mode.
In clock find source function, we get value 0x2 for clock selector
and 0x1 for clock source.

Kernel-4.14 behavior
Since clock source is valid so clock selector was not set again.
We pass through this function and start a playback stream(USB OUT transfer)
in 48Khz/32bit/2ch mode. This time we get value 0x1 for clock selector
and 0x1 for clock source. Finally clock id with this setting is 0x9.

Kernel-5.10 behavior
Clock selector was always set one more time even it is valid.
When we start a playback stream, we will get 0x2 for clock selector
and 0x1 for clock source. In this case clock id becomes 0xA.
This is an incorrect clock source setting and results in severe noises.
We see wrong data rate in USB IN transfer.
(From 288 bytes/ms becomes 144 bytes/ms) It should keep in 288 bytes/ms.

This earphone works fine on older kernel version load because
this is a newly-added behavior.

Fixes: d2e8f641257d ("ALSA: usb-audio: Explicitly set up the clock selector")
Signed-off-by: chihhao.chen <chihhao.chen@mediatek.com>
Link: https://lore.kernel.org/r/1627100621-19225-1-git-send-email-chihhao.chen@mediatek.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05 18:51:27 +02:00
Takashi Iwai
ad7736cebf ALSA: usb-audio: Explicitly set up the clock selector
commit d2e8f641257d0d3af6e45d6ac2d6f9d56b8ea964 upstream.

In the current code, we have some assumption that the audio clock
selector has been set up implicitly and don't want to touch it unless
it's really needed for the fallback autoclock setup.  This works for
most devices but some seem having a problem.  Partially this was
covered for the devices with a single connector at the initialization
phase (commit 086b957cc17f "ALSA: usb-audio: Skip the clock selector
inquiry for single connections"), but also there are cases where the
wrong clock set up is kept silently.  The latter seems to be the cause
of the noises on Behringer devices.

In this patch, we explicitly set up the audio clock selector whenever
the appropriate node is found.

Reported-by: Geraldo Nascimento <geraldogabriel@gmail.com>
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199327
Link: https://lore.kernel.org/r/CAEsQvcvF7LnO8PxyyCxuRCx=7jNeSCvFAd-+dE0g_rd1rOxxdw@mail.gmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210413084152.32325-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11 14:47:32 +02:00
Takashi Iwai
de8f8a38f2 ALSA: usb-audio: Disable sample read check if firmware doesn't give back
commit 9df28edce7c6ab38050235f6f8b43dd7ccd01b6d upstream.

Some buggy firmware don't give the current sample rate but leaves
zero.  Handle this case more gracefully without warning but just skip
the current rate verification from the next time.

Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201218145858.2357-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:54:07 +01:00
Gustavo A. R. Silva
c0dbbdad4e ALSA: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200708203236.GA5112@embeddedor
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-07-09 13:01:29 +02:00
Alexander Tsoy
2edb84e304 ALSA: usb-audio: Add support for MOTU MicroBook IIc
MicroBook IIc operates in UAC2 mode by default. This patch addresses
several issues with it:

- MicroBook II and IIc shares the same USB ID. We can distinguish them
  by interface class.
- MaxPacketsOnly attribute is erroneously set in endpoint descriptors.
  As a result this card produces noise with all sample rates other than
  96 KHz. This also causes issues like IOMMU page faults and other
  problems with host controller.
- Sample rate changes takes more than 2 seconds for this device. Clock
  validity request returns false during that period, so the clock validity
  quirk is required.

Signed-off-by: Alexander Tsoy <alexander@tsoy.me>
Link: https://lore.kernel.org/r/20200229151815.14199-1-alexander@tsoy.me
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-03-06 09:03:17 +01:00
Alexander Tsoy
9f35a31283 ALSA: usb-audio: Add clock validity quirk for Denon MC7000/MCX8000
It should be safe to ignore clock validity check result if the following
conditions are met:
 - only one single sample rate is supported;
 - the terminal is directly connected to the clock source;
 - the clock type is internal.

This is to deal with some Denon DJ controllers that always reports that
clock is invalid.

Tested-by: Tobias Oszlanyi <toszlanyi@yahoo.de>
Signed-off-by: Alexander Tsoy <alexander@tsoy.me>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200212235450.697348-1-alexander@tsoy.me
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-02-13 07:18:58 +01:00
Saurav Girepunje
1d4961d9eb ALSA: usb-audio: sound: usb: usb true/false for bool return type
Use true/false for bool type return in uac_clock_source_is_valid().

Signed-off-by: Saurav Girepunje <saurav.girepunje@gmail.com>
Link: https://lore.kernel.org/r/20191029175200.GA7320@saurav
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-10-30 08:46:33 +01:00
Takashi Iwai
b8e4f1fdfa ALSA: usb-audio: Remove superfluous bLength checks
Now that we got the more comprehensive validation code for USB-audio
descriptors, the check of overflow in each descriptor unit parser
became superfluous.  Drop some of the obvious cases.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-08-22 10:36:00 +02:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Adam Goode
58cabe8715 ALSA: usb-audio: Allow changing from a bad sample rate
If the audio device is externally clocked and set to a rate that does
not match the external clock, the clock will never be valid and we cannot
set the rate successfully. To fix this, allow a rate change even if
the clock is initially invalid, and validate again after the rate is
changed.

This fixes problems with MOTU UltraLite AVB hardware over USB.

Signed-off-by: Adam Goode <agoode@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-19 08:44:46 +02:00
Takashi Iwai
f25ecf8f98 ALSA: usb-audio: Follow standard coding style
Avoid if ((err = ...) style and expand to multiple lines instead.
No change in the end result, but just the beautification.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-28 14:52:40 +02:00
Ruslan Bilovol
17156f23e9 ALSA: usb: add UAC3 BADD profiles support
Recently released USB Audio Class 3.0 specification
contains BADD (Basic Audio Device Definition) document
which describes pre-defined UAC3 configurations.

BADD support is mandatory for UAC3 devices, it should be
implemented as a separate USB device configuration.
As per BADD document, class-specific descriptors
shall not be included in the Device’s Configuration
descriptor ("inferred"), but host can guess them
from BADD profile number, number of endpoints and
their max packed sizes.

This patch adds support of all BADD profiles from the spec

Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Tested-by: Jorge Sanjuan <jorge.sanjuan@codethink.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-13 08:54:35 +02:00
Takashi Iwai
b580fbfff1 ALSA: usb-audio: Add sanity checks in UAC3 clock parsers
The UAC3 clock parser codes lack of the sanity checks for malformed
descriptors like UAC2 parser does.  Without it, the driver may lead to
a potential crash.

Fixes: 9a2fe9b801 ("ALSA: usb: initial USB Audio Device Class 3.0 support")
Tested-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Reviewed-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-07 13:07:17 +02:00
Takashi Iwai
f5d76e9c40 ALSA: usb-audio: More strict sanity checks for clock parsers
The sanity checks introduced for malformed descriptors loosely check
the given descriptor size, although the size greater than the defined
description is invalid.  It was due to a concern of any funky firmware
in the actual products.  But this doesn't look hitting, and any sane
products must have the defined descriptors.

So in this patch, we make the validators more strict, allowing only
with the defined descriptor sizes.  The value in clock selector
validator is corrected from 5 to 7 to count the two unlisted fields
after baCSourceID[].

Suggested-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Reviewed-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-07 13:07:11 +02:00
Takashi Iwai
f7645bd636 ALSA: usb-audio: Refactor clock finder helpers
There are lots of open-coded functions to find a clock source,
selector and multiplier.  Now there are both v2 and v3, so six
variants.

This patch refactors the code to use a common helper for the main
loop, and define each validator function for each target.
There is no functional change.

Fixes: 9a2fe9b801 ("ALSA: usb: initial USB Audio Device Class 3.0 support")
Reviewed-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-07 13:07:05 +02:00
Andrew Chant
21e9b3e931 ALSA: usb-audio: fix uac control query argument
This patch fixes code readability and should have no functional change.

Correct uac control query functions to account for the 1-based indexing
of USB Audio Class control identifiers.

The function parameter, u8 control, should be the
constant defined in audio-v2.h to identify the control to be checked for
readability or writeability.

This patch fixes all callers that had adjusted, and makes explicit
the mapping between audio_feature_info[] array index and the associated
control identifier.

Signed-off-by: Andrew Chant <achant@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-23 10:25:03 +01:00
Ruslan Bilovol
9a2fe9b801 ALSA: usb: initial USB Audio Device Class 3.0 support
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@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-21 11:46:33 +01:00
Takashi Iwai
0a62d6c966 ALSA: usb-audio: Add sanity checks in v2 clock parsers
The helper functions to parse and look for the clock source, selector
and multiplier unit may return the descriptor with a too short length
than required, while there is no sanity check in the caller side.
Add some sanity checks in the parsers, at least, to guarantee the
given descriptor size, for avoiding the potential crashes.

Fixes: 79f920fbff ("ALSA: usb-audio: parse clock topology of UAC2 devices")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-11-21 17:50:34 +01:00
Takashi Iwai
57dd5414a0 ALSA: usb-audio: Limit retrying sample rate reads
There are many USB audio devices with buggy firmware that don't react
with the sample rate reading properly.  This often results in the
flood of error messages and slowing down the operation.

The sample rate read back is basically only for confirming the sample
rate setup, and it's not critically important.  As a compromise, in
this patch, we stop the sample rate read back once when the device
gives errors more than tolerance (twice, as of now).  This should
improve most of error cases while we still can catch the firmware
bugginess.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-04-29 11:49:04 +02:00
Takashi Iwai
447d6275f0 ALSA: usb-audio: Add sanity checks for endpoint accesses
Add some sanity check codes before actually accessing the endpoint via
get_endpoint() in order to avoid the invalid access through a
malformed USB descriptor.  Mostly just checking bNumEndpoints, but in
one place (snd_microii_spdif_default_get()), the validity of iface and
altsetting index is checked as well.

Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=971125
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-03-16 12:45:32 +01:00
Joe Turner
b62b998010 ALSA: usb-audio: Don't attempt to get Lifecam HD-5000 sample rate
Adds a quirk to disable the check that the sample rate has been set correctly, as the Lifecam does not support getting the sample rate.

This means that we don't need to wait for the USB timeout when attempting to get the sample rate. Waiting for the timeout causes problems in some applications, which give up on the device acquisition process before it has had time to complete, resulting in no sound.

[minor tidy up by tiwai]

Signed-off-by: Joe Turner <joe@oampo.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-17 07:20:04 +01:00
Takashi Iwai
0ba41d917e ALSA: usb-audio: Use standard printk helpers
Convert with dev_err() and co from snd_printk(), etc.
As there are too deep indirections (e.g. ep->chip->dev->dev),
a few new local macros, usb_audio_err() & co, are introduced.

Also, the device numbers in some messages are dropped, as they are
shown in the prefix automatically.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-02-26 16:45:34 +01:00
Clemens Ladisch
8f898e92ae ALSA: usb-audio: store protocol version in struct audioformat
Instead of reading bInterfaceProtocol from the descriptor whenever it's
needed, store this value in the audioformat structure.  Besides
simplifying some code, this will allow us to correctly handle vendor-
specific devices where the descriptors are marked with other values.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2013-06-27 21:59:47 +02:00
David Henningsson
fa92dd77ec ALSA: usb - Avoid unnecessary sample rate changes on USB 2.0 clock sources
The Scarlett 2i2 seems to take almost 500 ms to set the sample rate,
even if the clock is currently set to that value. This patch speeds
up prepare of the device, by avoiding setting the clock to something
it already is.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-26 07:37:09 +02:00
Daniel Mack
21bb5aafce ALSA: snd-usb: Playback Design: use usb_set_inferface quirk from more locations
It turns out the devices from Playback Design need the delay quirk
after usb_set_interface from clocks.c as well. Make it a proper
quirks function and factor out the code to quirks.c.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-10 09:21:43 +02:00
Eldad Zack
1dc669fed6 ALSA: usb-audio: UAC2: support read-only freq control
Some clocks might be read-only, e.g., external clocks (see also
UAC2 4.7.2.1).

In this case, setting the sample frequency will always fail
(even if the rate is equal to the current clock rate),
therefore do not write, but read the value and compare to the
requested rate.
If the clock is read only, avoid reading it twice.

If it doesn't match, return -ENXIO since the clock is invalid for
this configuration.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-04 08:32:07 +02:00
Eldad Zack
027bbc1546 ALSA: usb-audio: show err in set_sample_rate_v2 debug
Show the error code returned from the USB subsystem in
the debug messages.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-04 08:31:40 +02:00
Eldad Zack
ef02e29b01 ALSA: usb-audio: UAC2: auto clock selection module param
Add a module param to disable auto clock selection.
This is provided for users that expect the audio stream to
fail when the clock source is invalid (e.g., the word clock
was unintentionally disconnected).

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-04 08:31:32 +02:00
Eldad Zack
8c55af3f69 ALSA: usb-audio: UAC2: try to find and switch to valid clock
If a selector is available on a device, it may be pointing to a
clock source which is currently invalid.
If there is a valid clock source which can be selected, switch
to it.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-04 08:31:14 +02:00
Eldad Zack
06ffc1ebdd ALSA: usb-audio: UAC2: do clock validity check earlier
Move the check that parse_audio_format_rates_v2() do after
receiving the clock source entity ID directly into the find
function and add a validation flag to the function.

This patch does not introduce any logic flow change.

It is provided to allow introducing automatic clock switching
easier later. By moving this uac_clock_source_is_valid callsite,
2 additional callsites can be avoided.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-04 08:30:59 +02:00
Eldad Zack
f6a8bc70f8 ALSA: usb-audio: use endianness macros
Replace the endianness conversions with the kernel-wide swabbing macros
in get/set_sample_rate_v2.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-04 08:30:49 +02:00
Takashi Iwai
7c51746517 ALSA: usb-audio: Clean up the code in set_sample_rate_v2()
Just for cleaning up, introduce a new function get_sample_rate_v2()
for replacing two identical calls in set_sample_rate_v2().

No functional change.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-03 19:08:29 +02:00
Torstein Hegge
690a863ff0 ALSA: usb: Work around CM6631 sample rate change bug
The C-Media CM6631 USB receiver doesn't respond to changes in sample rate
while the interface is active. The same behavior is observed in other UAC2
hardware like the VIA VT1731.

Reset the interface after setting the sampling frequency on sample rate
changes, to ensure that the sample rate set by snd_usb_init_sample_rate() is
used. Otherwise, the device will try to use the sample rate of the previous
stream, causing distorted sound on sample rate changes.

The reset is performed for all UAC2 devices, as it should not affect a
standards compliant device, but it is only necessary for C-Media CM6631,
VIA VT1731 and possibly others.

Failure to read sample rate from the device is not handled as an error in
set_sample_rate_v2(), as (permanent or intermittent) failure to read sample
rate isn't essential for a successful sample rate set.

Signed-off-by: Torstein Hegge <hegge@resisty.net>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-04-03 17:05:44 +02:00
Daniel Mack
aff252a848 ALSA: snd-usb: fix clock source validity index
uac_clock_source_is_valid() uses the control selector value to access
the bmControls bitmap of the clock source unit. This is wrong, as
control selector values start from 1, while the bitmap uses all
available bits.

In other words, "Clock Validity Control" is stored in D3..2, not D5..4
of the clock selector unit's bmControls.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Reported-by: Andreas Koch <andreas@akdesigninc.com>
Cc: stable@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-08-01 10:24:16 +02:00
Clemens Ladisch
17d900c4a1 ALSA: usb-audio: increase control transfer timeout
There are certain devices that are reportedly so slow that they need
more than 100 ms to handle control transfers.  Therefore, increase the
timeout in mixer(_quirks).c to 1000 ms.

The timeout parameter of snd_usb_ctl_msg() is now constant, so we can
drop it.

Reported-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-09-27 09:21:48 +02:00
Daniel Mack
3bc6fbc743 ALSA: usb-audio: assume valid clock
If the interface can't report a clock's validity, assume that it's
valid.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Reported-by: Vicente Joel <vicentejoel@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-05-18 11:44:44 +02:00
Clemens Ladisch
a2acad8298 ALSA: usb-audio: fix detection of vendor-specific device protocol settings
The Audio Class v2 support code in 2.6.35 added checks for the
bInterfaceProtocol field.  However, there are devices (usually those
detected by vendor-specific quirks) that do not have one of the
predefined values in this field, which made the driver reject them.

To fix this regression, restore the old behaviour, i.e., assume that
a device with an unknown bInterfaceProtocol field (other than
UAC_VERSION_2) has more or less UAC-v1-compatible descriptors.

[compile warning fixes by tiwai]

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-03 22:36:39 +02:00
Clemens Ladisch
d32d552e66 ALSA: usb-audio: silence a superfluous warning
It is not advisable to print a warning when a device does not support
setting the sample rate because this is perfectly valid for devices with
a single rate or where rates are implicitly changed by selecting another
alternate setting.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-07-09 15:08:12 +02:00
Daniel Mack
3d8d4dcfd4 ALSA: usb-audio: simplify control interface access
As the control interface is now carried in struct snd_usb_audio, we can
simplify the API a little and also drop the private ctrlif field from
struct usb_mixer_interface.

Also remove a left-over function prototype in pcm.h.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-06-23 16:10:23 +02:00
Daniel Mack
157a57b6fa ALSA: usb-audio: move and add some comments
Also add a list of open topics.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-06-23 16:09:50 +02:00
Daniel Mack
f22aa94908 ALSA: usb-audio: clean up includes in clock.c
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-06-23 16:09:14 +02:00
Daniel Mack
11bcbc443a ALSA: usb-audio: fix control messages for USB_RECIP_INTERFACE
Control messages directed to an interface must have the interface number
set in the lower 8 bits of wIndex. This wasn't done correctly for some
clock and mixer messages.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Reported-by: Alex Lee <alexlee188@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-06-11 18:05:38 +02:00
Daniel Mack
79f920fbff ALSA: usb-audio: parse clock topology of UAC2 devices
Audio devices which comply to the UAC2 standard can export complex clock
topologies in its descriptors and set up links between them.

The entities that are defined are

 - clock sources, which define the end-leafs.
 - clock selectors, which act as switch to select one out of many
   possible clocks sources.
 - clock multipliers, which have an input clock source, and act as clock
   source again. They can be used to derive one clock from another.

All sample rate changes, clock validity queries and the like must go to
clock source elements, while clock selectors and multipliers can be used
as terminal clock source.

The following patch adds a parser for these elements and functions to
iterate over the tree and find the leaf nodes (clock sources).

The samplerate set functions were moved to the new clock.c file.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-05-31 18:16:59 +02:00