Commit Graph

8543 Commits

Author SHA1 Message Date
Takashi Iwai
9d0af44c2e Merge branch 'for-linus' into for-next
Resolved the merge conflict in HD-audio Tegra driver.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-20 11:44:51 +01:00
Takashi Iwai
4d024fe8f8 ALSA: hda: Apply aligned MMIO access only conditionally
It turned out that the recent simplification of HD-audio bus access
helpers caused a regression on the virtual HD-audio device on QEMU
with ARM platforms.  The driver got a CORB/RIRB timeout and couldn't
probe any codecs.

The essential difference that caused a problem was the enforced
aligned MMIO accesses by simplification.  Since snd-hda-tegra driver
is enabled on ARM, it enables CONFIG_SND_HDA_ALIGNED_MMIO, which makes
the all HD-audio drivers using the aligned MMIO accesses.  While this
is mandatory for snd-hda-tegra, it seems that snd-hda-intel on ARM
gets broken by this access pattern.

For addressing the regression, this patch introduces a new flag,
aligned_mmio, to hdac_bus object, and applies the aligned MMIO only
when this flag is set.  This change affects only platforms with
CONFIG_SND_HDA_ALIGNED_MMIO set, i.e. mostly only for ARM platforms.

Unfortunately the patch became a big bigger than it should be, just
because the former calls didn't take hdac_bus object in the argument,
hence we had to extend the call patterns.

Fixes: 19abfefd4c ("ALSA: hda: Direct MMIO accesses")
BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1161152
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200120104127.28985-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-20 11:42:15 +01:00
Kailang Yang
5af29028fd ALSA: hda/realtek - Add Headset Mic supported for HP cPC
HP ALC671 need to support Headset Mic.

Signed-off-by: Kailang Yang <kailang@realtek.com>
Link: https://lore.kernel.org/r/06a9d2b176e14706976d6584cbe2d92a@realtek.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-17 11:46:32 +01:00
Takashi Iwai
2ba0176c70 ALSA: hda/analog - Minor optimization for SPDIF mux connections
AD HD-audio codec driver has a few code lines invoking
snd_get_num_conns() and using its return value as the array index
without checking.  This is basically safe in all those places; at the
second and later calls snd_get_num_conns() returns the value cached
from the first invocation, hence the value is always consistent.

However, it looks a bit confusing as if a lack of the proper check.
This patch introduces a new field num_smux_conns in ad198x_spec for
simplifying the code.  Now we store and refer to the value more
locally without invoking the extra function at each time.

Reported-by: Colin King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200115100035.22511-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-16 17:29:17 +01:00
Pierre-Louis Bossart
75663c093d ALSA: hda: patch_hdmi: remove warnings with empty body
make W=1 reports the following warnings, fix as suggested

sound/pci/hda/patch_hdmi.c: In function ‘hdmi_non_intrinsic_event’:
sound/pci/hda/patch_hdmi.c:824:3: warning: suggest braces around empty
body in an ‘if’ statement [-Wempty-body]
  824 |   ;
      |   ^
sound/pci/hda/patch_hdmi.c:826:3: warning: suggest braces around empty
body in an ‘if’ statement [-Wempty-body]
  826 |   ;
      |   ^

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200113211405.28070-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-14 07:47:53 +01:00
Pierre-Louis Bossart
4f5c26534d ALSA: hda: correct kernel-doc parameter descriptions
make W=1 throws warnings, provide missing documentation

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200113211405.28070-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-14 07:47:44 +01:00
Takashi Iwai
1a462be52f ALSA: hda: Manage concurrent reg access more properly
In the commit 8e85def572 ("ALSA: hda: enable regmap internal
locking"), we re-enabled the regmap lock due to the reported
regression that showed the possible concurrent accesses.  It was a
temporary workaround, and there are still a few opened races even
after the revert.  In this patch, we cover those still opened windows
with a proper mutex lock and disable the regmap internal lock again.

First off, the patch introduces a new snd_hdac_device.regmap_lock
mutex that is applied for each snd_hdac_regmap_*() call, including
read, write and update helpers.  The mutex is applied carefully so
that it won't block the self-power-up procedure in the helper
function.  Also, this assures the protection for the accesses without
regmap, too.

The snd_hdac_regmap_update_raw() is refactored to use the standard
regmap_update_bits_check() function instead of the open-code.  The
non-regmap case is still open-coded but it's an easy part.  The all
read and write operations are in the single mutex protection, so it's
now race-free.

In addition, a couple of new helper functions are added:
snd_hdac_regmap_update_raw_once() and snd_hdac_regmap_sync().  Both
are called from HD-audio legacy driver.  The former is to initialize
the given verb bits but only once when it's not initialized yet.  Due
to this condition, the function invokes regcache_cache_only(), and
it's now performed inside the regmap_lock (formerly it was racy) too.
The latter function is for simply invoking regcache_sync() inside the
regmap_lock, which is called from the codec resume call path.
Along with that, the HD-audio codec driver code is slightly modified /
simplified to adapt those new functions.

And finally, snd_hdac_regmap_read_raw(), *_write_raw(), etc are
rewritten with the helper macro.  It's just for simplification because
the code logic is identical among all those functions.

Tested-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200109090104.26073-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-13 13:40:41 +01:00
Pierre-Louis Bossart
8a71821f12 ALSA: hda: patch_realtek: fix empty macro usage in if block
GCC reports the following warning with W=1

sound/pci/hda/patch_realtek.c: In function ‘alc269_suspend’:
sound/pci/hda/patch_realtek.c:3616:29: warning: suggest braces around
empty body in an ‘if’ statement [-Wempty-body]
 3616 |   alc5505_dsp_suspend(codec);
      |                             ^

sound/pci/hda/patch_realtek.c: In function ‘alc269_resume’:
sound/pci/hda/patch_realtek.c:3651:28: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
 3651 |   alc5505_dsp_resume(codec);
      |                            ^

This is a classic macro problem and can indeed lead to bad program
flows.

Fix by using the usual "do { } while (0)" pattern

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200111214736.3002-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-12 09:45:09 +01:00
Takashi Iwai
3cdca6d62b Merge branch 'for-linus' into for-next
Sync 5.5-devel branch once again for applying the HD-audio fixes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-11 09:03:40 +01:00
Takashi Iwai
7fba6aea44 ALSA: hda: Rename back to dmic_detect option
We've got quite a few bug reports showing the SOF driver being loaded
unintentionally recently, and the reason seems to be that users didn't
know the module option change: with the recent kernel, a new option
dsp_driver=1 has to be passed to a new module snd-intel-dspcfg
instead of snd_hda_intel.dmic_detect=0 option.

That is, actually there are two tricky things here:
- We changed the whole detection in another module and another
  option semantics.
- The existing option for skipping the DSP probe was also renamed.

For avoiding the confusion and giving user more hint, this patch
reverts the renamed option dsp_driver back to dmic_detect for
snd-hda-intel module, and show the warning about the module option
change when the non-default value is passed.

Fixes: 82d9d54a6c ("ALSA: hda: add Intel DSP configuration / probe code")
Link: https://lore.kernel.org/r/20200109082000.26729-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-11 09:02:23 +01:00
YueHaibing
55c203a308 ALSA: pci: echoaudio: remove set but not used variable 'chip'
sound/pci/echoaudio/echoaudio.c: In function snd_echo_mixer_info:
sound/pci/echoaudio/echoaudio.c:1233:20: warning: variable chip set but not used [-Wunused-but-set-variable]
sound/pci/echoaudio/echoaudio.c: In function 'snd_echo_vmixer_info':
sound/pci/echoaudio/echoaudio.c:1300:20: warning: variable 'chip' set but not used [-Wunused-but-set-variable]

commit e67c3f0fd4 ("ALSA: pci: echoaudio: remove usage
of dimen menber of elem_value structure") left behind this
unused variable.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200108125803.45584-1-yuehaibing@huawei.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-08 15:07:24 +01:00
Kailang Yang
54a6a7dc10 ALSA: hda/realtek - Add quirk for the bass speaker on Lenovo Yoga X1 7th gen
Add quirk to ALC285_FIXUP_SPEAKER2_TO_DAC1, which is the same fixup
applied for X1 Carbon 7th gen in commit d2cd795c4e ("ALSA: hda -
fixup for the bass speaker on Lenovo Carbon X1 7th gen").

Signed-off-by: Kailang Yang <kailang@realtek.com>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-08 10:46:33 +01:00
Kailang Yang
9194a1ebbc ALSA: hda/realtek - Set EAPD control to default for ALC222
Set EAPD control to verb control.

Signed-off-by: Kailang Yang <kailang@realtek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-08 09:48:36 +01:00
Takashi Iwai
a05c0737d3 ALSA: via82xx: More constification
Apply const prefix to the static table for the chip models.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-66-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:12 +01:00
Takashi Iwai
8045d0fc95 ALSA: fm801: More constification
Apply const prefix to the static register table.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-65-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:12 +01:00
Takashi Iwai
7103e4a70c ALSA: ens137x: More constification
Apply const prefix to the quirk entry, forgotten in the previous fix.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-64-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:11 +01:00
Takashi Iwai
9bca090793 ALSA: echoaudio: More constification
Apply const prefix to the static channel list table.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-63-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:10 +01:00
Takashi Iwai
e157f0cd05 ALSA: cs4281: More constification
Apply const prefix to the static register table.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-62-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:10 +01:00
Takashi Iwai
83fdb6fbcc ALSA: azt3328: More constification
Apply const prefix to the static initial register table.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-61-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:09 +01:00
Takashi Iwai
24ce8056a9 ALSA: ak4531: More constification
Apply const prefix to the initial register map.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-60-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:09 +01:00
Takashi Iwai
2f200ce291 ALSA: lx6464es: More constifications
Apply const prefix to the static tables for the DSP command and the
peak map.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-56-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:07 +01:00
Takashi Iwai
26170691ff ALSA: aw2: More constifications
Apply const prefix to the static parameter tables.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-55-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:15:06 +01:00
Takashi Iwai
5f3aca1065 ALSA: cmipci: More constifications
Apply const prefix to the static tables for rates, ports and
registers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-37-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:55 +01:00
Takashi Iwai
096da809f6 ALSA: es1968: More constifications
Apply const prefix to the quirk white/black lists.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-36-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:55 +01:00
Takashi Iwai
96d5ebf25e ALSA: es1938: More constifications
Apply const prefix to the static register table and its callers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-35-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:54 +01:00
Takashi Iwai
066c044b05 ALSA: atiixp: More constifications
Apply const prefix to the static register tables.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-34-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:54 +01:00
Takashi Iwai
9ca7a0c979 ALSA: asihpi: More constifications
Apply const prefix to each possible place: the static tables for
formats, parameters, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-33-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:53 +01:00
Takashi Iwai
6e0e75d94e ALSA: ctxfi: More constifications
Apply const prefix to each possible place: the DAIO tables and the
register offset table.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-32-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:52 +01:00
Takashi Iwai
9797430972 ALSA: ca0106: More constifications
Apply const prefix to each possible place: the static tables for
registers and verbs, and the string arrays.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-31-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:52 +01:00
Takashi Iwai
ba09f5d84e ALSA: cs46xx: More constifications
Apply const prefix to each possible place: the static tables for
registers and op codes, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-30-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:51 +01:00
Takashi Iwai
a7f7edcfa4 ALSA: korg1212: More constifications
Apply const prefix to each possible place: the string array, the
static tables for clock selectors, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-29-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:50 +01:00
Takashi Iwai
ccfacf2b2e ALSA: nm256: More constifications
Apply const prefix to the static tables coefs and init registers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-28-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:50 +01:00
Takashi Iwai
10aab1a24d ALSA: ymfpci: More constifications
Apply const prefix to each possible place: the static tables for
sample rates, parameters and registers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-26-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:49 +01:00
Takashi Iwai
3cfe54b96c ALSA: mixart: More constifications
Apply const prefix to each possible place: the string arrays and the
static tables for volumes.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-25-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:48 +01:00
Takashi Iwai
98fd539841 ALSA: pcxhr: More constifications
Apply const prefix to each possible place: the board parameters and
DSP command table, and the string arrays.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-24-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:47 +01:00
Takashi Iwai
1e393ef4e3 ALSA: rme9652: More constifications
Apply const prefix to the channel map tables.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-21-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:45 +01:00
Takashi Iwai
e315cc3f93 ALSA: hdspm: More constifications
Apply const prefix to each possible place: the string arrays, the
channel map tables and callers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-20-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:45 +01:00
Takashi Iwai
d92596402d ALSA: hdsp: More constifications
Apply const prefix to each channel map table and its callers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-19-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:44 +01:00
Takashi Iwai
f16a4e960a ALSA: ice1712: More constifications
Apply const prefix to each possible place: the EEPROM tables, the
static string arrays, the init verb tables, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-17-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:41 +01:00
Takashi Iwai
bf6f3d74c9 ALSA: riptide: More constifications
Apply const prefix to each lbus path table definition and its
callers.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-16-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:40 +01:00
Takashi Iwai
6fddce26f8 ALSA: emu10k1: More constifications
Apply const prefix to the remaining possible places: the static tables
for init verbs and registers, the string arrays, the conversion
tables, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-15-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:39 +01:00
Takashi Iwai
eafcdbdb4f ALSA: au88x0: More constifications
Apply const prefix to each possible place: the static register tables,
the coef tables, the string arrays, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-14-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:38 +01:00
Takashi Iwai
1675bfc0fb ALSA: ac97: More constifications
Apply const prefix to each possible place: the static tables for
registers and bits, the quirk tables, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-11-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:34 +01:00
Takashi Iwai
bf82326fce ALSA: hda: More constifications
Apply const prefix to the remaining possible places: the string
tables, the rate tables, the verb tables, the index tables, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-10-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:32 +01:00
Takashi Iwai
f729f88a04 ALSA: intel8x0: More constifications
Apply const prefix to more places: the static tables for PCM
definitions, the register tables, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-9-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:31 +01:00
Takashi Iwai
c09482455c ALSA: vx: More constifications
Apply const prefix to every possible place: the static tables for DSP
commands, the string tables, and register/offset tables.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-8-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:30 +01:00
Takashi Iwai
6b0f95c49d ALSA: hda/realtek - More constifications
Apply const prefix to each coef table array.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 16:14:27 +01:00
Takashi Iwai
5d8398aa59 Merge branch 'for-linus' into for-next
Merge 5.5-rc devel branch back for applying the conflicting USB-audio
fix.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 09:19:34 +01:00
Takashi Iwai
5fab582967 ALSA: hda/realtek - Apply mic mute LED quirk for Dell E7xx laptops, too
Dell E7xx laptops have also mic mute LED that is driven by the
dell-laptop platform driver.  Bind it with the capture control as
already done for other models.

A caveat is that the fixup hook for the mic mute LED has to be applied
at last, otherwise it results in the invalid override of the callback.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=205529
Link: https://lore.kernel.org/r/20200105081119.21396-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-05 09:12:11 +01:00
Takashi Iwai
fbd3eb7f66 ALSA: control: Add verification for kctl accesses
The current implementation of ALSA control API fully relies on the
callbacks of each driver, and there is no verification of the values
passed via API.  This patch is an attempt to improve the situation
slightly by adding the validation code for the values stored via info
and get callbacks.

The patch adds a new kconfig, CONFIG_SND_CTL_VALIDATION.  It depends
on CONFIG_SND_DEBUG and off as default since the validation would
require a slight overhead including the additional call of info
callback at each get callback invocation.

When this config is enabled, the values stored by each info callback
invocation are verified, namely:
- Whether the info type is valid
- Whether the number of enum items is non-zero
- Whether the given info count is within the allowed boundary

Similarly, the values stored at each get callback are verified as
well:
- Whether the values are within the given range
- Whether the values are aligned with the given step
- Whether any further changes are seen in the data array over the
  given info count

The last point helps identifying a possibly invalid data type access,
typically a case where the info callback declares the type being
SNDRV_CTL_ELEM_TYPE_ENUMERATED while the get/put callbacks store
the values in value.integer.value[] array.

When a validation fails, the ALSA core logs an error message including
the device and the control ID, and the API call also returns an
error.  So, with the new validation turned on, the driver behavior
difference may be visible on user-space, too -- it's intentional,
though, so that we can catch an error more clearly.

The patch also introduces a new ctl access type,
SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK.  A driver may pass this flag with
other access bits to indicate that the ctl element won't be verified.
It's useful when a driver code is specially written to access the data
greater than info->count size by some reason.  For example, this flag
is actually set now in HD-audio HDMI codec driver which needs to clear
the data array in the case of the disconnected monitor.

Also, the PCM channel-map helper code is slightly modified to avoid
the false-positive hit by this validation code, too.

Link: https://lore.kernel.org/r/20200104083556.27789-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-04 09:37:59 +01:00