Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) ==========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) Proc Files of ALSA Drivers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3) ==========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5) Takashi Iwai <tiwai@suse.de>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) General
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) =======
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) ALSA has its own proc tree, /proc/asound.  Many useful information are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) found in this tree.  When you encounter a problem and need debugging,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) check the files listed in the following sections.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) Each card has its subtree cardX, where X is from 0 to 7. The
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) card-specific files are stored in the ``card*`` subdirectories.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) Global Information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) ==================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) cards
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	Shows the list of currently configured ALSA drivers,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	index, the id string, short and long descriptions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) version
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	Shows the version string and compile date.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) modules
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	Lists the module of each card
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) devices
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	Lists the ALSA native device mappings.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) meminfo
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	Shows the status of allocated pages via ALSA drivers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	Appears only when ``CONFIG_SND_DEBUG=y``.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) hwdep
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	Lists the currently available hwdep devices in format of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	``<card>-<device>: <name>``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) pcm
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	Lists the currently available PCM devices in format of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	``<card>-<device>: <id>: <name> : <sub-streams>``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) timer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	Lists the currently available timer devices
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) oss/devices
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	Lists the OSS device mappings.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) oss/sndstat
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	Provides the output compatible with /dev/sndstat.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	You can symlink this to /dev/sndstat.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) Card Specific Files
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) ===================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) The card-specific files are found in ``/proc/asound/card*`` directories.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) Some drivers (e.g. cmipci) have their own proc entries for the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) register dump, etc (e.g. ``/proc/asound/card*/cmipci`` shows the register
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) dump).  These files would be really helpful for debugging.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) When PCM devices are available on this card, you can see directories
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) like pcm0p or pcm1c.  They hold the PCM information for each PCM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) stream.  The number after ``pcm`` is the PCM device number from 0, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) the last ``p`` or ``c`` means playback or capture direction.  The files in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) this subtree is described later.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) The status of MIDI I/O is found in ``midi*`` files.  It shows the device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) name and the received/transmitted bytes through the MIDI device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) When the card is equipped with AC97 codecs, there are ``codec97#*``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) subdirectories (described later).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) When the OSS mixer emulation is enabled (and the module is loaded),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) oss_mixer file appears here, too.  This shows the current mapping of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) OSS mixer elements to the ALSA control elements.  You can change the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) mapping by writing to this device.  Read OSS-Emulation.txt for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) details.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) PCM Proc Files
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) ==============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) ``card*/pcm*/info``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	The general information of this PCM device: card #, device #,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	substreams, etc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) ``card*/pcm*/xrun_debug``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	This file appears when ``CONFIG_SND_DEBUG=y`` and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	``CONFIG_SND_PCM_XRUN_DEBUG=y``.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	This shows the status of xrun (= buffer overrun/xrun) and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	invalid PCM position debug/check of ALSA PCM middle layer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	It takes an integer value, can be changed by writing to this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	file, such as::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		 # echo 5 > /proc/asound/card0/pcm0p/xrun_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	The value consists of the following bit flags:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	* bit 0 = Enable XRUN/jiffies debug messages
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	* bit 1 = Show stack trace at XRUN / jiffies check
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	* bit 2 = Enable additional jiffies check
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	When the bit 0 is set, the driver will show the messages to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	kernel log when an xrun is detected.  The debug message is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	shown also when the invalid H/W pointer is detected at the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 	update of periods (usually called from the interrupt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	handler).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	When the bit 1 is set, the driver will show the stack trace
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	additionally.  This may help the debugging.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	Since 2.6.30, this option can enable the hwptr check using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	jiffies.  This detects spontaneous invalid pointer callback
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	values, but can be lead to too much corrections for a (mostly
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	buggy) hardware that doesn't give smooth pointer updates.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	This feature is enabled via the bit 2.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) ``card*/pcm*/sub*/info``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	The general information of this PCM sub-stream.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) ``card*/pcm*/sub*/status``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	The current status of this PCM sub-stream, elapsed time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	H/W position, etc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) ``card*/pcm*/sub*/hw_params``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	The hardware parameters set for this sub-stream.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) ``card*/pcm*/sub*/sw_params``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	The soft parameters set for this sub-stream.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) ``card*/pcm*/sub*/prealloc``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	The buffer pre-allocation information.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) ``card*/pcm*/sub*/xrun_injection``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	Triggers an XRUN to the running stream when any value is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	written to this proc file.  Used for fault injection.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	This entry is write-only.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) AC97 Codec Information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) ======================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) ``card*/codec97#*/ac97#?-?``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	Shows the general information of this AC97 codec chip, such as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	name, capabilities, set up.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) ``card*/codec97#0/ac97#?-?+regs``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	Shows the AC97 register dump.  Useful for debugging.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	When CONFIG_SND_DEBUG is enabled, you can write to this file for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	changing an AC97 register directly.  Pass two hex numbers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	For example,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) ::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	# echo 02 9f1f > /proc/asound/card0/codec97#0/ac97#0-0+regs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) USB Audio Streams
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) =================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) ``card*/stream*``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	Shows the assignment and the current status of each audio stream
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	of the given card.  This information is very useful for debugging.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) HD-Audio Codecs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) ===============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) ``card*/codec#*``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	Shows the general codec information and the attribute of each
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	widget node.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) ``card*/eld#*``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	Available for HDMI or DisplayPort interfaces.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	Shows ELD(EDID Like Data) info retrieved from the attached HDMI sink,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	and describes its audio capabilities and configurations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	Some ELD fields may be modified by doing ``echo name hex_value > eld#*``.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	Only do this if you are sure the HDMI sink provided value is wrong.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	And if that makes your HDMI audio work, please report to us so that we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 	can fix it in future kernel releases.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) Sequencer Information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) =====================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) seq/drivers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	Lists the currently available ALSA sequencer drivers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) seq/clients
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 	Shows the list of currently available sequencer clients and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	ports.  The connection status and the running status are shown
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 	in this file, too.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) seq/queues
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 	Lists the currently allocated/running sequencer queues.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) seq/timer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 	Lists the currently allocated/running sequencer timers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) seq/oss
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	Lists the OSS-compatible sequencer stuffs.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) Help For Debugging?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) ===================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) When the problem is related with PCM, first try to turn on xrun_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) mode.  This will give you the kernel messages when and where xrun
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) happened.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) If it's really a bug, report it with the following information:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) - the name of the driver/card, show in ``/proc/asound/cards``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) - the register dump, if available (e.g. ``card*/cmipci``)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) when it's a PCM problem,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) - set-up of PCM, shown in hw_parms, sw_params, and status in the PCM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225)   sub-stream directory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) when it's a mixer problem,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) - AC97 proc files, ``codec97#*/*`` files
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) for USB audio/midi,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) - output of ``lsusb -v``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) - ``stream*`` files in card directory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) The ALSA bug-tracking system is found at:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) https://bugtrack.alsa-project.org/alsa-bug/