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1=============================2More Notes on HD-Audio Driver3=============================4 5Takashi Iwai <tiwai@suse.de>6 7 8General9=======10 11HD-audio is the new standard on-board audio component on modern PCs12after AC97. Although Linux has been supporting HD-audio since long13time ago, there are often problems with new machines. A part of the14problem is broken BIOS, and the rest is the driver implementation.15This document explains the brief trouble-shooting and debugging16methods for the HD-audio hardware.17 18The HD-audio component consists of two parts: the controller chip and19the codec chips on the HD-audio bus. Linux provides a single driver20for all controllers, snd-hda-intel. Although the driver name contains21a word of a well-known hardware vendor, it's not specific to it but for22all controller chips by other companies. Since the HD-audio23controllers are supposed to be compatible, the single snd-hda-driver24should work in most cases. But, not surprisingly, there are known25bugs and issues specific to each controller type. The snd-hda-intel26driver has a bunch of workarounds for these as described below.27 28A controller may have multiple codecs. Usually you have one audio29codec and optionally one modem codec. In theory, there might be30multiple audio codecs, e.g. for analog and digital outputs, and the31driver might not work properly because of conflict of mixer elements.32This should be fixed in future if such hardware really exists.33 34The snd-hda-intel driver has several different codec parsers depending35on the codec. It has a generic parser as a fallback, but this36functionality is fairly limited until now. Instead of the generic37parser, usually the codec-specific parser (coded in patch_*.c) is used38for the codec-specific implementations. The details about the39codec-specific problems are explained in the later sections.40 41If you are interested in the deep debugging of HD-audio, read the42HD-audio specification at first. The specification is found on43Intel's web page, for example:44 45* https://www.intel.com/standards/hdaudio/46 47 48HD-Audio Controller49===================50 51DMA-Position Problem52--------------------53The most common problem of the controller is the inaccurate DMA54pointer reporting. The DMA pointer for playback and capture can be55read in two ways, either via a LPIB register or via a position-buffer56map. As default the driver tries to read from the io-mapped57position-buffer, and falls back to LPIB if the position-buffer appears58dead. However, this detection isn't perfect on some devices. In such59a case, you can change the default method via ``position_fix`` option.60 61``position_fix=1`` means to use LPIB method explicitly.62``position_fix=2`` means to use the position-buffer.63``position_fix=3`` means to use a combination of both methods, needed64for some VIA controllers. The capture stream position is corrected65by comparing both LPIB and position-buffer values.66``position_fix=4`` is another combination available for all controllers,67and uses LPIB for the playback and the position-buffer for the capture68streams.69``position_fix=5`` is specific to Intel platforms, so far, for Skylake70and onward. It applies the delay calculation for the precise position71reporting.72``position_fix=6`` is to correct the position with the fixed FIFO73size, mainly targeted for the recent AMD controllers.740 is the default value for all other75controllers, the automatic check and fallback to LPIB as described in76the above. If you get a problem of repeated sounds, this option might77help.78 79In addition to that, every controller is known to be broken regarding80the wake-up timing. It wakes up a few samples before actually81processing the data on the buffer. This caused a lot of problems, for82example, with ALSA dmix or JACK. Since 2.6.27 kernel, the driver puts83an artificial delay to the wake up timing. This delay is controlled84via ``bdl_pos_adj`` option.85 86When ``bdl_pos_adj`` is a negative value (as default), it's assigned to87an appropriate value depending on the controller chip. For Intel88chips, it'd be 1 while it'd be 32 for others. Usually this works.89Only in case it doesn't work and you get warning messages, you should90change this parameter to other values.91 92 93Codec-Probing Problem94---------------------95A less often but a more severe problem is the codec probing. When96BIOS reports the available codec slots wrongly, the driver gets97confused and tries to access the non-existing codec slot. This often98results in the total screw-up, and destructs the further communication99with the codec chips. The symptom appears usually as error messages100like:101::102 103 hda_intel: azx_get_response timeout, switching to polling mode:104 last cmd=0x12345678105 hda_intel: azx_get_response timeout, switching to single_cmd mode:106 last cmd=0x12345678107 108The first line is a warning, and this is usually relatively harmless.109It means that the codec response isn't notified via an IRQ. The110driver uses explicit polling method to read the response. It gives111very slight CPU overhead, but you'd unlikely notice it.112 113The second line is, however, a fatal error. If this happens, usually114it means that something is really wrong. Most likely you are115accessing a non-existing codec slot.116 117Thus, if the second error message appears, try to narrow the probed118codec slots via ``probe_mask`` option. It's a bitmask, and each bit119corresponds to the codec slot. For example, to probe only the first120slot, pass ``probe_mask=1``. For the first and the third slots, pass121``probe_mask=5`` (where 5 = 1 | 4), and so on.122 123Since 2.6.29 kernel, the driver has a more robust probing method, so124this error might happen rarely, though.125 126On a machine with a broken BIOS, sometimes you need to force the127driver to probe the codec slots the hardware doesn't report for use.128In such a case, turn the bit 8 (0x100) of ``probe_mask`` option on.129Then the rest 8 bits are passed as the codec slots to probe130unconditionally. For example, ``probe_mask=0x103`` will force to probe131the codec slots 0 and 1 no matter what the hardware reports.132 133 134Interrupt Handling135------------------136HD-audio driver uses MSI as default (if available) since 2.6.33137kernel as MSI works better on some machines, and in general, it's138better for performance. However, Nvidia controllers showed bad139regressions with MSI (especially in a combination with AMD chipset),140thus we disabled MSI for them.141 142There seem also still other devices that don't work with MSI. If you143see a regression wrt the sound quality (stuttering, etc) or a lock-up144in the recent kernel, try to pass ``enable_msi=0`` option to disable145MSI. If it works, you can add the known bad device to the blacklist146defined in hda_intel.c. In such a case, please report and give the147patch back to the upstream developer.148 149 150HD-Audio Codec151==============152 153Model Option154------------155The most common problem regarding the HD-audio driver is the156unsupported codec features or the mismatched device configuration.157Most of codec-specific code has several preset models, either to158override the BIOS setup or to provide more comprehensive features.159 160The driver checks PCI SSID and looks through the static configuration161table until any matching entry is found. If you have a new machine,162you may see a message like below:163::164 165 hda_codec: ALC880: BIOS auto-probing.166 167Meanwhile, in the earlier versions, you would see a message like:168::169 170 hda_codec: Unknown model for ALC880, trying auto-probe from BIOS...171 172Even if you see such a message, DON'T PANIC. Take a deep breath and173keep your towel. First of all, it's an informational message, no174warning, no error. This means that the PCI SSID of your device isn't175listed in the known preset model (white-)list. But, this doesn't mean176that the driver is broken. Many codec-drivers provide the automatic177configuration mechanism based on the BIOS setup.178 179The HD-audio codec has usually "pin" widgets, and BIOS sets the default180configuration of each pin, which indicates the location, the181connection type, the jack color, etc. The HD-audio driver can guess182the right connection judging from these default configuration values.183However -- some codec-support codes, such as patch_analog.c, don't184support the automatic probing (yet as of 2.6.28). And, BIOS is often,185yes, pretty often broken. It sets up wrong values and screws up the186driver.187 188The preset model (or recently called as "fix-up") is provided189basically to overcome such a situation. When the matching preset190model is found in the white-list, the driver assumes the static191configuration of that preset with the correct pin setup, etc.192Thus, if you have a newer machine with a slightly different PCI SSID193(or codec SSID) from the existing one, you may have a good chance to194re-use the same model. You can pass the ``model`` option to specify the195preset model instead of PCI (and codec-) SSID look-up.196 197What ``model`` option values are available depends on the codec chip.198Check your codec chip from the codec proc file (see "Codec Proc-File"199section below). It will show the vendor/product name of your codec200chip. Then, see Documentation/sound/hd-audio/models.rst file,201the section of HD-audio driver. You can find a list of codecs202and ``model`` options belonging to each codec. For example, for Realtek203ALC262 codec chip, pass ``model=ultra`` for devices that are compatible204with Samsung Q1 Ultra.205 206Thus, the first thing you can do for any brand-new, unsupported and207non-working HD-audio hardware is to check HD-audio codec and several208different ``model`` option values. If you have any luck, some of them209might suit with your device well.210 211There are a few special model option values:212 213* when 'nofixup' is passed, the device-specific fixups in the codec214 parser are skipped.215* when ``generic`` is passed, the codec-specific parser is skipped and216 only the generic parser is used.217 218A new style for the model option that was introduced since 5.15 kernel219is to pass the PCI or codec SSID in the form of ``model=XXXX:YYYY``220where XXXX and YYYY are the sub-vendor and sub-device IDs in hex221numbers, respectively. This is a kind of aliasing to another device;222when this form is given, the driver will refer to that SSID as a223reference to the quirk table. It'd be useful especially when the224target quirk isn't listed in the model table. For example, passing225model=103c:8862 will apply the quirk for HP ProBook 445 G8 (which226isn't found in the model table as of writing) as long as the device is227handled equivalently by the same driver.228 229 230Speaker and Headphone Output231----------------------------232One of the most frequent (and obvious) bugs with HD-audio is the233silent output from either or both of a built-in speaker and a234headphone jack. In general, you should try a headphone output at235first. A speaker output often requires more additional controls like236the external amplifier bits. Thus a headphone output has a slightly237better chance.238 239Before making a bug report, double-check whether the mixer is set up240correctly. The recent version of snd-hda-intel driver provides mostly241"Master" volume control as well as "Front" volume (where Front242indicates the front-channels). In addition, there can be individual243"Headphone" and "Speaker" controls.244 245Ditto for the speaker output. There can be "External Amplifier"246switch on some codecs. Turn on this if present.247 248Another related problem is the automatic mute of speaker output by249headphone plugging. This feature is implemented in most cases, but250not on every preset model or codec-support code.251 252In anyway, try a different model option if you have such a problem.253Some other models may match better and give you more matching254functionality. If none of the available models works, send a bug255report. See the bug report section for details.256 257If you are masochistic enough to debug the driver problem, note the258following:259 260* The speaker (and the headphone, too) output often requires the261 external amplifier. This can be set usually via EAPD verb or a262 certain GPIO. If the codec pin supports EAPD, you have a better263 chance via SET_EAPD_BTL verb (0x70c). On others, GPIO pin (mostly264 it's either GPIO0 or GPIO1) may turn on/off EAPD.265* Some Realtek codecs require special vendor-specific coefficients to266 turn on the amplifier. See patch_realtek.c.267* IDT codecs may have extra power-enable/disable controls on each268 analog pin. See patch_sigmatel.c.269* Very rare but some devices don't accept the pin-detection verb until270 triggered. Issuing GET_PIN_SENSE verb (0xf09) may result in the271 codec-communication stall. Some examples are found in272 patch_realtek.c.273 274 275Capture Problems276----------------277The capture problems are often because of missing setups of mixers.278Thus, before submitting a bug report, make sure that you set up the279mixer correctly. For example, both "Capture Volume" and "Capture280Switch" have to be set properly in addition to the right "Capture281Source" or "Input Source" selection. Some devices have "Mic Boost"282volume or switch.283 284When the PCM device is opened via "default" PCM (without pulse-audio285plugin), you'll likely have "Digital Capture Volume" control as well.286This is provided for the extra gain/attenuation of the signal in287software, especially for the inputs without the hardware volume288control such as digital microphones. Unless really needed, this289should be set to exactly 50%, corresponding to 0dB -- neither extra290gain nor attenuation. When you use "hw" PCM, i.e., a raw access PCM,291this control will have no influence, though.292 293It's known that some codecs / devices have fairly bad analog circuits,294and the recorded sound contains a certain DC-offset. This is no bug295of the driver.296 297Most of modern laptops have no analog CD-input connection. Thus, the298recording from CD input won't work in many cases although the driver299provides it as the capture source. Use CDDA instead.300 301The automatic switching of the built-in and external mic per plugging302is implemented on some codec models but not on every model. Partly303because of my laziness but mostly lack of testers. Feel free to304submit the improvement patch to the author.305 306 307Direct Debugging308----------------309If no model option gives you a better result, and you are a tough guy310to fight against evil, try debugging via hitting the raw HD-audio311codec verbs to the device. Some tools are available: hda-emu and312hda-analyzer. The detailed description is found in the sections313below. You'd need to enable hwdep for using these tools. See "Kernel314Configuration" section.315 316 317Other Issues318============319 320Kernel Configuration321--------------------322In general, I recommend you to enable the sound debug option,323``CONFIG_SND_DEBUG=y``, no matter whether you are debugging or not.324 325Don't forget to turn on the appropriate ``CONFIG_SND_HDA_CODEC_*``326options. Note that each of them corresponds to the codec chip, not327the controller chip. Thus, even if lspci shows the Nvidia controller,328you may need to choose the option for other vendors. If you are329unsure, just select all yes.330 331``CONFIG_SND_HDA_HWDEP`` is a useful option for debugging the driver.332When this is enabled, the driver creates hardware-dependent devices333(one per each codec), and you have a raw access to the device via334these device files. For example, ``hwC0D2`` will be created for the335codec slot #2 of the first card (#0). For debug-tools such as336hda-verb and hda-analyzer, the hwdep device has to be enabled.337Thus, it'd be better to turn this on always.338 339``CONFIG_SND_HDA_RECONFIG`` is a new option, and this depends on the340hwdep option above. When enabled, you'll have some sysfs files under341the corresponding hwdep directory. See "HD-audio reconfiguration"342section below.343 344``CONFIG_SND_HDA_POWER_SAVE`` option enables the power-saving feature.345See "Power-saving" section below.346 347 348Codec Proc-File349---------------350The codec proc-file is a treasure-chest for debugging HD-audio.351It shows most of useful information of each codec widget.352 353The proc file is located in /proc/asound/card*/codec#*, one file per354each codec slot. You can know the codec vendor, product id and355names, the type of each widget, capabilities and so on.356This file, however, doesn't show the jack sensing state, so far. This357is because the jack-sensing might be depending on the trigger state.358 359This file will be picked up by the debug tools, and also it can be fed360to the emulator as the primary codec information. See the debug tools361section below.362 363This proc file can be also used to check whether the generic parser is364used. When the generic parser is used, the vendor/product ID name365will appear as "Realtek ID 0262", instead of "Realtek ALC262".366 367 368HD-Audio Reconfiguration369------------------------370This is an experimental feature to allow you re-configure the HD-audio371codec dynamically without reloading the driver. The following sysfs372files are available under each codec-hwdep device directory (e.g.373/sys/class/sound/hwC0D0):374 375vendor_id376 Shows the 32bit codec vendor-id hex number. You can change the377 vendor-id value by writing to this file.378subsystem_id379 Shows the 32bit codec subsystem-id hex number. You can change the380 subsystem-id value by writing to this file.381revision_id382 Shows the 32bit codec revision-id hex number. You can change the383 revision-id value by writing to this file.384afg385 Shows the AFG ID. This is read-only.386mfg387 Shows the MFG ID. This is read-only.388name389 Shows the codec name string. Can be changed by writing to this390 file.391modelname392 Shows the currently set ``model`` option. Can be changed by writing393 to this file.394init_verbs395 The extra verbs to execute at initialization. You can add a verb by396 writing to this file. Pass three numbers: nid, verb and parameter397 (separated with a space).398hints399 Shows / stores hint strings for codec parsers for any use.400 Its format is ``key = value``. For example, passing ``jack_detect = no``401 will disable the jack detection of the machine completely.402init_pin_configs403 Shows the initial pin default config values set by BIOS.404driver_pin_configs405 Shows the pin default values set by the codec parser explicitly.406 This doesn't show all pin values but only the changed values by407 the parser. That is, if the parser doesn't change the pin default408 config values by itself, this will contain nothing.409user_pin_configs410 Shows the pin default config values to override the BIOS setup.411 Writing this (with two numbers, NID and value) appends the new412 value. The given will be used instead of the initial BIOS value at413 the next reconfiguration time. Note that this config will override414 even the driver pin configs, too.415reconfig416 Triggers the codec re-configuration. When any value is written to417 this file, the driver re-initialize and parses the codec tree418 again. All the changes done by the sysfs entries above are taken419 into account.420clear421 Resets the codec, removes the mixer elements and PCM stuff of the422 specified codec, and clear all init verbs and hints.423 424For example, when you want to change the pin default configuration425value of the pin widget 0x14 to 0x9993013f, and let the driver426re-configure based on that state, run like below:427::428 429 # echo 0x14 0x9993013f > /sys/class/sound/hwC0D0/user_pin_configs430 # echo 1 > /sys/class/sound/hwC0D0/reconfig431 432 433Hint Strings434------------435The codec parser have several switches and adjustment knobs for436matching better with the actual codec or device behavior. Many of437them can be adjusted dynamically via "hints" strings as mentioned in438the section above. For example, by passing ``jack_detect = no`` string439via sysfs or a patch file, you can disable the jack detection, thus440the codec parser will skip the features like auto-mute or mic441auto-switch. As a boolean value, either ``yes``, ``no``, ``true``, ``false``,442``1`` or ``0`` can be passed.443 444The generic parser supports the following hints:445 446jack_detect (bool)447 specify whether the jack detection is available at all on this448 machine; default true449inv_jack_detect (bool)450 indicates that the jack detection logic is inverted451trigger_sense (bool)452 indicates that the jack detection needs the explicit call of453 AC_VERB_SET_PIN_SENSE verb454inv_eapd (bool)455 indicates that the EAPD is implemented in the inverted logic456pcm_format_first (bool)457 sets the PCM format before the stream tag and channel ID458sticky_stream (bool)459 keep the PCM format, stream tag and ID as long as possible;460 default true461spdif_status_reset (bool)462 reset the SPDIF status bits at each time the SPDIF stream is set463 up464pin_amp_workaround (bool)465 the output pin may have multiple amp values466single_adc_amp (bool)467 ADCs can have only single input amps468auto_mute (bool)469 enable/disable the headphone auto-mute feature; default true470auto_mic (bool)471 enable/disable the mic auto-switch feature; default true472line_in_auto_switch (bool)473 enable/disable the line-in auto-switch feature; default false474need_dac_fix (bool)475 limits the DACs depending on the channel count476primary_hp (bool)477 probe headphone jacks as the primary outputs; default true478multi_io (bool)479 try probing multi-I/O config (e.g. shared line-in/surround,480 mic/clfe jacks)481multi_cap_vol (bool)482 provide multiple capture volumes483inv_dmic_split (bool)484 provide split internal mic volume/switch for phase-inverted485 digital mics486indep_hp (bool)487 provide the independent headphone PCM stream and the corresponding488 mixer control, if available489add_stereo_mix_input (bool)490 add the stereo mix (analog-loopback mix) to the input mux if491 available492add_jack_modes (bool)493 add "xxx Jack Mode" enum controls to each I/O jack for allowing to494 change the headphone amp and mic bias VREF capabilities495power_save_node (bool)496 advanced power management for each widget, controlling the power497 state (D0/D3) of each widget node depending on the actual pin and498 stream states499power_down_unused (bool)500 power down the unused widgets, a subset of power_save_node, and501 will be dropped in future502add_hp_mic (bool)503 add the headphone to capture source if possible504hp_mic_detect (bool)505 enable/disable the hp/mic shared input for a single built-in mic506 case; default true507vmaster (bool)508 enable/disable the virtual Master control; default true509mixer_nid (int)510 specifies the widget NID of the analog-loopback mixer511 512 513Early Patching514--------------515When ``CONFIG_SND_HDA_PATCH_LOADER=y`` is set, you can pass a "patch"516as a firmware file for modifying the HD-audio setup before517initializing the codec. This can work basically like the518reconfiguration via sysfs in the above, but it does it before the519first codec configuration.520 521A patch file is a plain text file which looks like below:522 523::524 525 [codec]526 0x12345678 0xabcd1234 2527 528 [model]529 auto530 531 [pincfg]532 0x12 0x411111f0533 534 [verb]535 0x20 0x500 0x03536 0x20 0x400 0xff537 538 [hint]539 jack_detect = no540 541 542The file needs to have a line ``[codec]``. The next line should contain543three numbers indicating the codec vendor-id (0x12345678 in the544example), the codec subsystem-id (0xabcd1234) and the address (2) of545the codec. The rest patch entries are applied to this specified codec546until another codec entry is given. Passing 0 or a negative number to547the first or the second value will make the check of the corresponding548field be skipped. It'll be useful for really broken devices that don't549initialize SSID properly.550 551The ``[model]`` line allows to change the model name of the each codec.552In the example above, it will be changed to model=auto.553Note that this overrides the module option.554 555After the ``[pincfg]`` line, the contents are parsed as the initial556default pin-configurations just like ``user_pin_configs`` sysfs above.557The values can be shown in user_pin_configs sysfs file, too.558 559Similarly, the lines after ``[verb]`` are parsed as ``init_verbs``560sysfs entries, and the lines after ``[hint]`` are parsed as ``hints``561sysfs entries, respectively.562 563Another example to override the codec vendor id from 0x12345678 to5640xdeadbeef is like below:565::566 567 [codec]568 0x12345678 0xabcd1234 2569 570 [vendor_id]571 0xdeadbeef572 573 574In the similar way, you can override the codec subsystem_id via575``[subsystem_id]``, the revision id via ``[revision_id]`` line.576Also, the codec chip name can be rewritten via ``[chip_name]`` line.577::578 579 [codec]580 0x12345678 0xabcd1234 2581 582 [subsystem_id]583 0xffff1111584 585 [revision_id]586 0x10587 588 [chip_name]589 My-own NEWS-0002590 591 592The hd-audio driver reads the file via request_firmware(). Thus,593a patch file has to be located on the appropriate firmware path,594typically, /lib/firmware. For example, when you pass the option595``patch=hda-init.fw``, the file /lib/firmware/hda-init.fw must be596present.597 598The patch module option is specific to each card instance, and you599need to give one file name for each instance, separated by commas.600For example, if you have two cards, one for an on-board analog and one601for an HDMI video board, you may pass patch option like below:602::603 604 options snd-hda-intel patch=on-board-patch,hdmi-patch605 606 607Power-Saving608------------609The power-saving is a kind of auto-suspend of the device. When the610device is inactive for a certain time, the device is automatically611turned off to save the power. The time to go down is specified via612``power_save`` module option, and this option can be changed dynamically613via sysfs.614 615The power-saving won't work when the analog loopback is enabled on616some codecs. Make sure that you mute all unneeded signal routes when617you want the power-saving.618 619The power-saving feature might cause audible click noises at each620power-down/up depending on the device. Some of them might be621solvable, but some are hard, I'm afraid. Some distros such as622openSUSE enables the power-saving feature automatically when the power623cable is unplugged. Thus, if you hear noises, suspect first the624power-saving. See /sys/module/snd_hda_intel/parameters/power_save to625check the current value. If it's non-zero, the feature is turned on.626 627The recent kernel supports the runtime PM for the HD-audio controller628chip, too. It means that the HD-audio controller is also powered up /629down dynamically. The feature is enabled only for certain controller630chips like Intel LynxPoint. You can enable/disable this feature631forcibly by setting ``power_save_controller`` option, which is also632available at /sys/module/snd_hda_intel/parameters directory.633 634 635Tracepoints636-----------637The hd-audio driver gives a few basic tracepoints.638``hda:hda_send_cmd`` traces each CORB write while ``hda:hda_get_response``639traces the response from RIRB (only when read from the codec driver).640``hda:hda_bus_reset`` traces the bus-reset due to fatal error, etc,641``hda:hda_unsol_event`` traces the unsolicited events, and642``hda:hda_power_down`` and ``hda:hda_power_up`` trace the power down/up643via power-saving behavior.644 645Enabling all tracepoints can be done like646::647 648 # echo 1 > /sys/kernel/tracing/events/hda/enable649 650then after some commands, you can traces from651/sys/kernel/tracing/trace file. For example, when you want to652trace what codec command is sent, enable the tracepoint like:653::654 655 # cat /sys/kernel/tracing/trace656 # tracer: nop657 #658 # TASK-PID CPU# TIMESTAMP FUNCTION659 # | | | | |660 <...>-7807 [002] 105147.774889: hda_send_cmd: [0:0] val=e3a019661 <...>-7807 [002] 105147.774893: hda_send_cmd: [0:0] val=e39019662 <...>-7807 [002] 105147.999542: hda_send_cmd: [0:0] val=e3a01a663 <...>-7807 [002] 105147.999543: hda_send_cmd: [0:0] val=e3901a664 <...>-26764 [001] 349222.837143: hda_send_cmd: [0:0] val=e3a019665 <...>-26764 [001] 349222.837148: hda_send_cmd: [0:0] val=e39019666 <...>-26764 [001] 349223.058539: hda_send_cmd: [0:0] val=e3a01a667 <...>-26764 [001] 349223.058541: hda_send_cmd: [0:0] val=e3901a668 669Here ``[0:0]`` indicates the card number and the codec address, and670``val`` shows the value sent to the codec, respectively. The value is671a packed value, and you can decode it via hda-decode-verb program672included in hda-emu package below. For example, the value e3a019 is673to set the left output-amp value to 25.674::675 676 % hda-decode-verb 0xe3a019677 raw value = 0x00e3a019678 cid = 0, nid = 0x0e, verb = 0x3a0, parm = 0x19679 raw value: verb = 0x3a0, parm = 0x19680 verbname = set_amp_gain_mute681 amp raw val = 0xa019682 output, left, idx=0, mute=0, val=25683 684 685Development Tree686----------------687The latest development codes for HD-audio are found on sound git tree:688 689* git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git690 691The master branch or for-next branches can be used as the main692development branches in general while the development for the current693and next kernels are found in for-linus and for-next branches,694respectively.695 696 697Sending a Bug Report698--------------------699If any model or module options don't work for your device, it's time700to send a bug report to the developers. Give the following in your701bug report:702 703* Hardware vendor, product and model names704* Kernel version (and ALSA-driver version if you built externally)705* ``alsa-info.sh`` output; run with ``--no-upload`` option. See the706 section below about alsa-info707 708If it's a regression, at best, send alsa-info outputs of both working709and non-working kernels. This is really helpful because we can710compare the codec registers directly.711 712Send a bug report either the following:713 714kernel-bugzilla715 https://bugzilla.kernel.org/716alsa-devel ML717 alsa-devel@alsa-project.org718 719 720Debug Tools721===========722 723This section describes some tools available for debugging HD-audio724problems.725 726alsa-info727---------728The script ``alsa-info.sh`` is a very useful tool to gather the audio729device information. It's included in alsa-utils package. The latest730version can be found on git repository:731 732* git://git.alsa-project.org/alsa-utils.git733 734The script can be fetched directly from the following URL, too:735 736* https://www.alsa-project.org/alsa-info.sh737 738Run this script as root, and it will gather the important information739such as the module lists, module parameters, proc file contents740including the codec proc files, mixer outputs and the control741elements. As default, it will store the information onto a web server742on alsa-project.org. But, if you send a bug report, it'd be better to743run with ``--no-upload`` option, and attach the generated file.744 745There are some other useful options. See ``--help`` option output for746details.747 748When a probe error occurs or when the driver obviously assigns a749mismatched model, it'd be helpful to load the driver with750``probe_only=1`` option (at best after the cold reboot) and run751alsa-info at this state. With this option, the driver won't configure752the mixer and PCM but just tries to probe the codec slot. After753probing, the proc file is available, so you can get the raw codec754information before modified by the driver. Of course, the driver755isn't usable with ``probe_only=1``. But you can continue the756configuration via hwdep sysfs file if hda-reconfig option is enabled.757Using ``probe_only`` mask 2 skips the reset of HDA codecs (use758``probe_only=3`` as module option). The hwdep interface can be used759to determine the BIOS codec initialization.760 761 762hda-verb763--------764hda-verb is a tiny program that allows you to access the HD-audio765codec directly. You can execute a raw HD-audio codec verb with this.766This program accesses the hwdep device, thus you need to enable the767kernel config ``CONFIG_SND_HDA_HWDEP=y`` beforehand.768 769The hda-verb program takes four arguments: the hwdep device file, the770widget NID, the verb and the parameter. When you access to the codec771on the slot 2 of the card 0, pass /dev/snd/hwC0D2 to the first772argument, typically. (However, the real path name depends on the773system.)774 775The second parameter is the widget number-id to access. The third776parameter can be either a hex/digit number or a string corresponding777to a verb. Similarly, the last parameter is the value to write, or778can be a string for the parameter type.779 780::781 782 % hda-verb /dev/snd/hwC0D0 0x12 0x701 2783 nid = 0x12, verb = 0x701, param = 0x2784 value = 0x0785 786 % hda-verb /dev/snd/hwC0D0 0x0 PARAMETERS VENDOR_ID787 nid = 0x0, verb = 0xf00, param = 0x0788 value = 0x10ec0262789 790 % hda-verb /dev/snd/hwC0D0 2 set_a 0xb080791 nid = 0x2, verb = 0x300, param = 0xb080792 value = 0x0793 794 795Although you can issue any verbs with this program, the driver state796won't be always updated. For example, the volume values are usually797cached in the driver, and thus changing the widget amp value directly798via hda-verb won't change the mixer value.799 800The hda-verb program is included now in alsa-tools:801 802* git://git.alsa-project.org/alsa-tools.git803 804Also, the old stand-alone package is found in the ftp directory:805 806* ftp://ftp.suse.com/pub/people/tiwai/misc/807 808Also a git repository is available:809 810* git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/hda-verb.git811 812See README file in the tarball for more details about hda-verb813program.814 815 816hda-analyzer817------------818hda-analyzer provides a graphical interface to access the raw HD-audio819control, based on pyGTK2 binding. It's a more powerful version of820hda-verb. The program gives you an easy-to-use GUI stuff for showing821the widget information and adjusting the amp values, as well as the822proc-compatible output.823 824The hda-analyzer:825 826* https://git.alsa-project.org/?p=alsa.git;a=tree;f=hda-analyzer827 828is a part of alsa.git repository in alsa-project.org:829 830* git://git.alsa-project.org/alsa.git831 832Codecgraph833----------834Codecgraph is a utility program to generate a graph and visualizes the835codec-node connection of a codec chip. It's especially useful when836you analyze or debug a codec without a proper datasheet. The program837parses the given codec proc file and converts to SVG via graphiz838program.839 840The tarball and GIT trees are found in the web page at:841 842* http://helllabs.org/codecgraph/843 844 845hda-emu846-------847hda-emu is an HD-audio emulator. The main purpose of this program is848to debug an HD-audio codec without the real hardware. Thus, it849doesn't emulate the behavior with the real audio I/O, but it just850dumps the codec register changes and the ALSA-driver internal changes851at probing and operating the HD-audio driver.852 853The program requires a codec proc-file to simulate. Get a proc file854for the target codec beforehand, or pick up an example codec from the855codec proc collections in the tarball. Then, run the program with the856proc file, and the hda-emu program will start parsing the codec file857and simulates the HD-audio driver:858 859::860 861 % hda-emu codecs/stac9200-dell-d820-laptop862 # Parsing..863 hda_codec: Unknown model for STAC9200, using BIOS defaults864 hda_codec: pin nid 08 bios pin config 40c003fa865 ....866 867 868The program gives you only a very dumb command-line interface. You869can get a proc-file dump at the current state, get a list of control870(mixer) elements, set/get the control element value, simulate the PCM871operation, the jack plugging simulation, etc.872 873The program is found in the git repository below:874 875* git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/hda-emu.git876 877See README file in the repository for more details about hda-emu878program.879 880 881hda-jack-retask882---------------883hda-jack-retask is a user-friendly GUI program to manipulate the884HD-audio pin control for jack retasking. If you have a problem about885the jack assignment, try this program and check whether you can get886useful results. Once when you figure out the proper pin assignment,887it can be fixed either in the driver code statically or via passing a888firmware patch file (see "Early Patching" section).889 890The program is included in alsa-tools now:891 892* git://git.alsa-project.org/alsa-tools.git893