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Takashi Iwaia7fe49b2008-12-03 18:26:35 +01001MORE NOTES ON HD-AUDIO DRIVER
2=============================
3 Takashi Iwai <tiwai@suse.de>
4
5
6GENERAL
7-------
8
9HD-audio is the new standard on-board audio component on modern PCs
10after AC97. Although Linux has been supporting HD-audio since long
11time ago, there are often problems with new machines. A part of the
Takashi Iwaid2afbe72008-12-10 09:28:15 +010012problem is broken BIOS, and the rest is the driver implementation.
13This document explains the brief trouble-shooting and debugging
14methods for the HD-audio hardware.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010015
16The HD-audio component consists of two parts: the controller chip and
17the codec chips on the HD-audio bus. Linux provides a single driver
Takashi Iwaid2afbe72008-12-10 09:28:15 +010018for all controllers, snd-hda-intel. Although the driver name contains
Matt LaPlante19f59462009-04-27 15:06:31 +020019a word of a well-known hardware vendor, it's not specific to it but for
Takashi Iwaid2afbe72008-12-10 09:28:15 +010020all controller chips by other companies. Since the HD-audio
21controllers are supposed to be compatible, the single snd-hda-driver
22should work in most cases. But, not surprisingly, there are known
23bugs and issues specific to each controller type. The snd-hda-intel
24driver has a bunch of workarounds for these as described below.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010025
26A controller may have multiple codecs. Usually you have one audio
Takashi Iwaid2afbe72008-12-10 09:28:15 +010027codec and optionally one modem codec. In theory, there might be
28multiple audio codecs, e.g. for analog and digital outputs, and the
29driver might not work properly because of conflict of mixer elements.
30This should be fixed in future if such hardware really exists.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010031
32The snd-hda-intel driver has several different codec parsers depending
33on the codec. It has a generic parser as a fallback, but this
34functionality is fairly limited until now. Instead of the generic
35parser, usually the codec-specific parser (coded in patch_*.c) is used
36for the codec-specific implementations. The details about the
37codec-specific problems are explained in the later sections.
38
39If you are interested in the deep debugging of HD-audio, read the
40HD-audio specification at first. The specification is found on
41Intel's web page, for example:
42
43- http://www.intel.com/standards/hdaudio/
44
45
46HD-AUDIO CONTROLLER
47-------------------
48
49DMA-Position Problem
50~~~~~~~~~~~~~~~~~~~~
51The most common problem of the controller is the inaccurate DMA
52pointer reporting. The DMA pointer for playback and capture can be
53read in two ways, either via a LPIB register or via a position-buffer
Takashi Iwaid2afbe72008-12-10 09:28:15 +010054map. As default the driver tries to read from the io-mapped
55position-buffer, and falls back to LPIB if the position-buffer appears
56dead. However, this detection isn't perfect on some devices. In such
57a case, you can change the default method via `position_fix` option.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010058
59`position_fix=1` means to use LPIB method explicitly.
60`position_fix=2` means to use the position-buffer. 0 is the default
Takashi Iwaid2afbe72008-12-10 09:28:15 +010061value, the automatic check and fallback to LPIB as described in the
62above. If you get a problem of repeated sounds, this option might
63help.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010064
65In addition to that, every controller is known to be broken regarding
66the wake-up timing. It wakes up a few samples before actually
67processing the data on the buffer. This caused a lot of problems, for
68example, with ALSA dmix or JACK. Since 2.6.27 kernel, the driver puts
69an artificial delay to the wake up timing. This delay is controlled
70via `bdl_pos_adj` option.
71
72When `bdl_pos_adj` is a negative value (as default), it's assigned to
73an appropriate value depending on the controller chip. For Intel
Takashi Iwaid2afbe72008-12-10 09:28:15 +010074chips, it'd be 1 while it'd be 32 for others. Usually this works.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010075Only in case it doesn't work and you get warning messages, you should
Takashi Iwaid2afbe72008-12-10 09:28:15 +010076change this parameter to other values.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010077
78
79Codec-Probing Problem
80~~~~~~~~~~~~~~~~~~~~~
81A less often but a more severe problem is the codec probing. When
82BIOS reports the available codec slots wrongly, the driver gets
83confused and tries to access the non-existing codec slot. This often
Takashi Iwaid2afbe72008-12-10 09:28:15 +010084results in the total screw-up, and destructs the further communication
85with the codec chips. The symptom appears usually as error messages
86like:
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010087------------------------------------------------------------------------
Takashi Iwaid2afbe72008-12-10 09:28:15 +010088 hda_intel: azx_get_response timeout, switching to polling mode:
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010089 last cmd=0x12345678
Takashi Iwaid2afbe72008-12-10 09:28:15 +010090 hda_intel: azx_get_response timeout, switching to single_cmd mode:
Takashi Iwaia7fe49b2008-12-03 18:26:35 +010091 last cmd=0x12345678
92------------------------------------------------------------------------
93
94The first line is a warning, and this is usually relatively harmless.
95It means that the codec response isn't notified via an IRQ. The
96driver uses explicit polling method to read the response. It gives
97very slight CPU overhead, but you'd unlikely notice it.
98
99The second line is, however, a fatal error. If this happens, usually
100it means that something is really wrong. Most likely you are
101accessing a non-existing codec slot.
102
103Thus, if the second error message appears, try to narrow the probed
104codec slots via `probe_mask` option. It's a bitmask, and each bit
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100105corresponds to the codec slot. For example, to probe only the first
106slot, pass `probe_mask=1`. For the first and the third slots, pass
107`probe_mask=5` (where 5 = 1 | 4), and so on.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100108
109Since 2.6.29 kernel, the driver has a more robust probing method, so
110this error might happen rarely, though.
111
Takashi Iwaiae374d62009-02-13 08:33:55 +0100112On a machine with a broken BIOS, sometimes you need to force the
113driver to probe the codec slots the hardware doesn't report for use.
114In such a case, turn the bit 8 (0x100) of `probe_mask` option on.
115Then the rest 8 bits are passed as the codec slots to probe
116unconditionally. For example, `probe_mask=0x103` will force to probe
117the codec slots 0 and 1 no matter what the hardware reports.
118
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100119
120Interrupt Handling
121~~~~~~~~~~~~~~~~~~
122In rare but some cases, the interrupt isn't properly handled as
123default. You would notice this by the DMA transfer error reported by
124ALSA PCM core, for example. Using MSI might help in such a case.
125Pass `enable_msi=1` option for enabling MSI.
126
127
128HD-AUDIO CODEC
129--------------
130
131Model Option
132~~~~~~~~~~~~
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100133The most common problem regarding the HD-audio driver is the
134unsupported codec features or the mismatched device configuration.
135Most of codec-specific code has several preset models, either to
136override the BIOS setup or to provide more comprehensive features.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100137
138The driver checks PCI SSID and looks through the static configuration
139table until any matching entry is found. If you have a new machine,
140you may see a message like below:
141------------------------------------------------------------------------
Takashi Iwai9a11f1a2009-07-28 16:01:20 +0200142 hda_codec: ALC880: BIOS auto-probing.
143------------------------------------------------------------------------
144Meanwhile, in the earlier versions, you would see a message like:
145------------------------------------------------------------------------
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100146 hda_codec: Unknown model for ALC880, trying auto-probe from BIOS...
147------------------------------------------------------------------------
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100148Even if you see such a message, DON'T PANIC. Take a deep breath and
149keep your towel. First of all, it's an informational message, no
150warning, no error. This means that the PCI SSID of your device isn't
151listed in the known preset model (white-)list. But, this doesn't mean
152that the driver is broken. Many codec-drivers provide the automatic
153configuration mechanism based on the BIOS setup.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100154
155The HD-audio codec has usually "pin" widgets, and BIOS sets the default
156configuration of each pin, which indicates the location, the
157connection type, the jack color, etc. The HD-audio driver can guess
158the right connection judging from these default configuration values.
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100159However -- some codec-support codes, such as patch_analog.c, don't
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100160support the automatic probing (yet as of 2.6.28). And, BIOS is often,
161yes, pretty often broken. It sets up wrong values and screws up the
162driver.
163
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100164The preset model is provided basically to overcome such a situation.
165When the matching preset model is found in the white-list, the driver
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100166assumes the static configuration of that preset and builds the mixer
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100167elements and PCM streams based on the static information. Thus, if
168you have a newer machine with a slightly different PCI SSID from the
169existing one, you may have a good chance to re-use the same model.
170You can pass the `model` option to specify the preset model instead of
171PCI SSID look-up.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100172
173What `model` option values are available depends on the codec chip.
174Check your codec chip from the codec proc file (see "Codec Proc-File"
175section below). It will show the vendor/product name of your codec
Justin Mattock83b20862009-04-14 14:31:21 -0700176chip. Then, see Documentation/sound/alsa/HD-Audio-Models.txt file,
Takashi Iwai692f9042008-12-19 12:44:46 +0100177the section of HD-audio driver. You can find a list of codecs
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100178and `model` options belonging to each codec. For example, for Realtek
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100179ALC262 codec chip, pass `model=ultra` for devices that are compatible
180with Samsung Q1 Ultra.
181
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100182Thus, the first thing you can do for any brand-new, unsupported and
183non-working HD-audio hardware is to check HD-audio codec and several
Justin Mattock83b20862009-04-14 14:31:21 -0700184different `model` option values. If you have any luck, some of them
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100185might suit with your device well.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100186
187Some codecs such as ALC880 have a special model option `model=test`.
188This configures the driver to provide as many mixer controls as
189possible for every single pin feature except for the unsolicited
190events (and maybe some other specials). Adjust each mixer element and
191try the I/O in the way of trial-and-error until figuring out the whole
192I/O pin mappings.
193
194Note that `model=generic` has a special meaning. It means to use the
195generic parser regardless of the codec. Usually the codec-specific
196parser is much better than the generic parser (as now). Thus this
197option is more about the debugging purpose.
198
199
200Speaker and Headphone Output
201~~~~~~~~~~~~~~~~~~~~~~~~~~~~
202One of the most frequent (and obvious) bugs with HD-audio is the
203silent output from either or both of a built-in speaker and a
204headphone jack. In general, you should try a headphone output at
205first. A speaker output often requires more additional controls like
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100206the external amplifier bits. Thus a headphone output has a slightly
207better chance.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100208
209Before making a bug report, double-check whether the mixer is set up
210correctly. The recent version of snd-hda-intel driver provides mostly
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100211"Master" volume control as well as "Front" volume (where Front
212indicates the front-channels). In addition, there can be individual
213"Headphone" and "Speaker" controls.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100214
215Ditto for the speaker output. There can be "External Amplifier"
216switch on some codecs. Turn on this if present.
217
218Another related problem is the automatic mute of speaker output by
219headphone plugging. This feature is implemented in most cases, but
220not on every preset model or codec-support code.
221
222In anyway, try a different model option if you have such a problem.
223Some other models may match better and give you more matching
224functionality. If none of the available models works, send a bug
225report. See the bug report section for details.
226
227If you are masochistic enough to debug the driver problem, note the
228following:
229
230- The speaker (and the headphone, too) output often requires the
231 external amplifier. This can be set usually via EAPD verb or a
232 certain GPIO. If the codec pin supports EAPD, you have a better
233 chance via SET_EAPD_BTL verb (0x70c). On others, GPIO pin (mostly
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100234 it's either GPIO0 or GPIO1) may turn on/off EAPD.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100235- Some Realtek codecs require special vendor-specific coefficients to
236 turn on the amplifier. See patch_realtek.c.
237- IDT codecs may have extra power-enable/disable controls on each
238 analog pin. See patch_sigmatel.c.
239- Very rare but some devices don't accept the pin-detection verb until
240 triggered. Issuing GET_PIN_SENSE verb (0xf09) may result in the
241 codec-communication stall. Some examples are found in
242 patch_realtek.c.
243
244
245Capture Problems
246~~~~~~~~~~~~~~~~
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100247The capture problems are often because of missing setups of mixers.
248Thus, before submitting a bug report, make sure that you set up the
249mixer correctly. For example, both "Capture Volume" and "Capture
250Switch" have to be set properly in addition to the right "Capture
251Source" or "Input Source" selection. Some devices have "Mic Boost"
252volume or switch.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100253
254When the PCM device is opened via "default" PCM (without pulse-audio
255plugin), you'll likely have "Digital Capture Volume" control as well.
256This is provided for the extra gain/attenuation of the signal in
257software, especially for the inputs without the hardware volume
258control such as digital microphones. Unless really needed, this
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100259should be set to exactly 50%, corresponding to 0dB -- neither extra
260gain nor attenuation. When you use "hw" PCM, i.e., a raw access PCM,
261this control will have no influence, though.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100262
263It's known that some codecs / devices have fairly bad analog circuits,
264and the recorded sound contains a certain DC-offset. This is no bug
265of the driver.
266
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100267Most of modern laptops have no analog CD-input connection. Thus, the
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100268recording from CD input won't work in many cases although the driver
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100269provides it as the capture source. Use CDDA instead.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100270
271The automatic switching of the built-in and external mic per plugging
272is implemented on some codec models but not on every model. Partly
273because of my laziness but mostly lack of testers. Feel free to
274submit the improvement patch to the author.
275
276
277Direct Debugging
278~~~~~~~~~~~~~~~~
Takashi Iwaif8bbd062008-12-11 13:12:59 +0100279If no model option gives you a better result, and you are a tough guy
Takashi Iwai623b9f62008-12-11 07:44:18 +0100280to fight against evil, try debugging via hitting the raw HD-audio
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100281codec verbs to the device. Some tools are available: hda-emu and
282hda-analyzer. The detailed description is found in the sections
283below. You'd need to enable hwdep for using these tools. See "Kernel
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100284Configuration" section.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100285
286
287OTHER ISSUES
288------------
289
290Kernel Configuration
291~~~~~~~~~~~~~~~~~~~~
292In general, I recommend you to enable the sound debug option,
293`CONFIG_SND_DEBUG=y`, no matter whether you are debugging or not.
294This enables snd_printd() macro and others, and you'll get additional
295kernel messages at probing.
296
297In addition, you can enable `CONFIG_SND_DEBUG_VERBOSE=y`. But this
298will give you far more messages. Thus turn this on only when you are
299sure to want it.
300
301Don't forget to turn on the appropriate `CONFIG_SND_HDA_CODEC_*`
302options. Note that each of them corresponds to the codec chip, not
303the controller chip. Thus, even if lspci shows the Nvidia controller,
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100304you may need to choose the option for other vendors. If you are
305unsure, just select all yes.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100306
307`CONFIG_SND_HDA_HWDEP` is a useful option for debugging the driver.
308When this is enabled, the driver creates hardware-dependent devices
309(one per each codec), and you have a raw access to the device via
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100310these device files. For example, `hwC0D2` will be created for the
311codec slot #2 of the first card (#0). For debug-tools such as
312hda-verb and hda-analyzer, the hwdep device has to be enabled.
313Thus, it'd be better to turn this on always.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100314
315`CONFIG_SND_HDA_RECONFIG` is a new option, and this depends on the
316hwdep option above. When enabled, you'll have some sysfs files under
317the corresponding hwdep directory. See "HD-audio reconfiguration"
318section below.
319
320`CONFIG_SND_HDA_POWER_SAVE` option enables the power-saving feature.
321See "Power-saving" section below.
322
323
324Codec Proc-File
325~~~~~~~~~~~~~~~
326The codec proc-file is a treasure-chest for debugging HD-audio.
327It shows most of useful information of each codec widget.
328
329The proc file is located in /proc/asound/card*/codec#*, one file per
330each codec slot. You can know the codec vendor, product id and
331names, the type of each widget, capabilities and so on.
332This file, however, doesn't show the jack sensing state, so far. This
333is because the jack-sensing might be depending on the trigger state.
334
335This file will be picked up by the debug tools, and also it can be fed
336to the emulator as the primary codec information. See the debug tools
337section below.
338
339This proc file can be also used to check whether the generic parser is
340used. When the generic parser is used, the vendor/product ID name
341will appear as "Realtek ID 0262", instead of "Realtek ALC262".
342
343
344HD-Audio Reconfiguration
345~~~~~~~~~~~~~~~~~~~~~~~~
346This is an experimental feature to allow you re-configure the HD-audio
347codec dynamically without reloading the driver. The following sysfs
348files are available under each codec-hwdep device directory (e.g.
349/sys/class/sound/hwC0D0):
350
351vendor_id::
352 Shows the 32bit codec vendor-id hex number. You can change the
353 vendor-id value by writing to this file.
354subsystem_id::
355 Shows the 32bit codec subsystem-id hex number. You can change the
356 subsystem-id value by writing to this file.
357revision_id::
358 Shows the 32bit codec revision-id hex number. You can change the
359 revision-id value by writing to this file.
360afg::
361 Shows the AFG ID. This is read-only.
362mfg::
363 Shows the MFG ID. This is read-only.
364name::
365 Shows the codec name string. Can be changed by writing to this
366 file.
367modelname::
368 Shows the currently set `model` option. Can be changed by writing
369 to this file.
370init_verbs::
371 The extra verbs to execute at initialization. You can add a verb by
Takashi Iwaid02b1f32009-03-02 17:34:51 +0100372 writing to this file. Pass three numbers: nid, verb and parameter
373 (separated with a space).
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100374hints::
Takashi Iwaid02b1f32009-03-02 17:34:51 +0100375 Shows / stores hint strings for codec parsers for any use.
376 Its format is `key = value`. For example, passing `hp_detect = yes`
377 to IDT/STAC codec parser will result in the disablement of the
378 headphone detection.
Takashi Iwaif1085c42009-02-20 14:50:35 +0100379init_pin_configs::
380 Shows the initial pin default config values set by BIOS.
Takashi Iwai346ff702009-02-23 09:42:57 +0100381driver_pin_configs::
Takashi Iwaif1085c42009-02-20 14:50:35 +0100382 Shows the pin default values set by the codec parser explicitly.
383 This doesn't show all pin values but only the changed values by
384 the parser. That is, if the parser doesn't change the pin default
385 config values by itself, this will contain nothing.
Takashi Iwai346ff702009-02-23 09:42:57 +0100386user_pin_configs::
387 Shows the pin default config values to override the BIOS setup.
388 Writing this (with two numbers, NID and value) appends the new
389 value. The given will be used instead of the initial BIOS value at
Takashi Iwai5e7b8e02009-02-23 09:45:59 +0100390 the next reconfiguration time. Note that this config will override
391 even the driver pin configs, too.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100392reconfig::
393 Triggers the codec re-configuration. When any value is written to
394 this file, the driver re-initialize and parses the codec tree
395 again. All the changes done by the sysfs entries above are taken
396 into account.
397clear::
398 Resets the codec, removes the mixer elements and PCM stuff of the
399 specified codec, and clear all init verbs and hints.
400
Takashi Iwai39c28712009-02-23 14:14:51 +0100401For example, when you want to change the pin default configuration
402value of the pin widget 0x14 to 0x9993013f, and let the driver
403re-configure based on that state, run like below:
404------------------------------------------------------------------------
405 # echo 0x14 0x9993013f > /sys/class/sound/hwC0D0/user_pin_configs
406 # echo 1 > /sys/class/sound/hwC0D0/reconfig
407------------------------------------------------------------------------
408
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100409
Takashi Iwai76824822009-06-17 17:17:18 +0200410Early Patching
411~~~~~~~~~~~~~~
412When CONFIG_SND_HDA_PATCH_LOADER=y is set, you can pass a "patch" as a
413firmware file for modifying the HD-audio setup before initializing the
414codec. This can work basically like the reconfiguration via sysfs in
415the above, but it does it before the first codec configuration.
416
Takashi Iwai1e7b8c82009-06-17 17:30:54 +0200417A patch file is a plain text file which looks like below:
Takashi Iwai76824822009-06-17 17:17:18 +0200418
419------------------------------------------------------------------------
420 [codec]
421 0x12345678 0xabcd1234 2
422
423 [model]
424 auto
425
426 [pincfg]
427 0x12 0x411111f0
428
429 [verb]
430 0x20 0x500 0x03
431 0x20 0x400 0xff
432
433 [hint]
434 hp_detect = yes
435------------------------------------------------------------------------
436
437The file needs to have a line `[codec]`. The next line should contain
438three numbers indicating the codec vendor-id (0x12345678 in the
439example), the codec subsystem-id (0xabcd1234) and the address (2) of
440the codec. The rest patch entries are applied to this specified codec
441until another codec entry is given.
442
443The `[model]` line allows to change the model name of the each codec.
444In the example above, it will be changed to model=auto.
445Note that this overrides the module option.
446
447After the `[pincfg]` line, the contents are parsed as the initial
448default pin-configurations just like `user_pin_configs` sysfs above.
449The values can be shown in user_pin_configs sysfs file, too.
450
451Similarly, the lines after `[verb]` are parsed as `init_verbs`
452sysfs entries, and the lines after `[hint]` are parsed as `hints`
453sysfs entries, respectively.
454
Takashi Iwai1e7b8c82009-06-17 17:30:54 +0200455The hd-audio driver reads the file via request_firmware(). Thus,
456a patch file has to be located on the appropriate firmware path,
457typically, /lib/firmware. For example, when you pass the option
458`patch=hda-init.fw`, the file /lib/firmware/hda-init-fw must be
459present.
460
461The patch module option is specific to each card instance, and you
462need to give one file name for each instance, separated by commas.
463For example, if you have two cards, one for an on-board analog and one
464for an HDMI video board, you may pass patch option like below:
465------------------------------------------------------------------------
466 options snd-hda-intel patch=on-board-patch,hdmi-patch
467------------------------------------------------------------------------
468
Takashi Iwai76824822009-06-17 17:17:18 +0200469
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100470Power-Saving
471~~~~~~~~~~~~
472The power-saving is a kind of auto-suspend of the device. When the
473device is inactive for a certain time, the device is automatically
474turned off to save the power. The time to go down is specified via
475`power_save` module option, and this option can be changed dynamically
476via sysfs.
477
478The power-saving won't work when the analog loopback is enabled on
479some codecs. Make sure that you mute all unneeded signal routes when
480you want the power-saving.
481
482The power-saving feature might cause audible click noises at each
483power-down/up depending on the device. Some of them might be
484solvable, but some are hard, I'm afraid. Some distros such as
485openSUSE enables the power-saving feature automatically when the power
486cable is unplugged. Thus, if you hear noises, suspect first the
Takashi Iwai623b9f62008-12-11 07:44:18 +0100487power-saving. See /sys/module/snd_hda_intel/parameters/power_save to
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100488check the current value. If it's non-zero, the feature is turned on.
489
490
Takashi Iwai132bb7c2008-12-11 15:39:52 +0100491Development Tree
492~~~~~~~~~~~~~~~~
493The latest development codes for HD-audio are found on sound git tree:
494
495- git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6.git
496
497The master branch or for-next branches can be used as the main
498development branches in general while the HD-audio specific patches
499are committed in topic/hda branch.
500
501If you are using the latest Linus tree, it'd be better to pull the
502above GIT tree onto it. If you are using the older kernels, an easy
503way to try the latest ALSA code is to build from the snapshot
504tarball. There are daily tarballs and the latest snapshot tarball.
505All can be built just like normal alsa-driver release packages, that
506is, installed via the usual spells: configure, make and make
507install(-modules). See INSTALL in the package. The snapshot tarballs
508are found at:
509
510- ftp://ftp.kernel.org/pub/linux/kernel/people/tiwai/snapshot/
511
512
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100513Sending a Bug Report
514~~~~~~~~~~~~~~~~~~~~
515If any model or module options don't work for your device, it's time
516to send a bug report to the developers. Give the following in your
517bug report:
518
519- Hardware vendor, product and model names
520- Kernel version (and ALSA-driver version if you built externally)
521- `alsa-info.sh` output; run with `--no-upload` option. See the
522 section below about alsa-info
523
524If it's a regression, at best, send alsa-info outputs of both working
525and non-working kernels. This is really helpful because we can
526compare the codec registers directly.
527
528Send a bug report either the followings:
529
530kernel-bugzilla::
531 http://bugme.linux-foundation.org/
532alsa-devel ML::
533 alsa-devel@alsa-project.org
534
535
536DEBUG TOOLS
537-----------
538
539This section describes some tools available for debugging HD-audio
540problems.
541
542alsa-info
543~~~~~~~~~
544The script `alsa-info.sh` is a very useful tool to gather the audio
545device information. You can fetch the latest version from:
546
547- http://www.alsa-project.org/alsa-info.sh
548
549Run this script as root, and it will gather the important information
550such as the module lists, module parameters, proc file contents
551including the codec proc files, mixer outputs and the control
552elements. As default, it will store the information onto a web server
553on alsa-project.org. But, if you send a bug report, it'd be better to
554run with `--no-upload` option, and attach the generated file.
555
556There are some other useful options. See `--help` option output for
557details.
558
Takashi Iwaiae374d62009-02-13 08:33:55 +0100559When a probe error occurs or when the driver obviously assigns a
560mismatched model, it'd be helpful to load the driver with
561`probe_only=1` option (at best after the cold reboot) and run
562alsa-info at this state. With this option, the driver won't configure
563the mixer and PCM but just tries to probe the codec slot. After
564probing, the proc file is available, so you can get the raw codec
565information before modified by the driver. Of course, the driver
566isn't usable with `probe_only=1`. But you can continue the
567configuration via hwdep sysfs file if hda-reconfig option is enabled.
568
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100569
570hda-verb
571~~~~~~~~
572hda-verb is a tiny program that allows you to access the HD-audio
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100573codec directly. You can execute a raw HD-audio codec verb with this.
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100574This program accesses the hwdep device, thus you need to enable the
575kernel config `CONFIG_SND_HDA_HWDEP=y` beforehand.
576
577The hda-verb program takes four arguments: the hwdep device file, the
578widget NID, the verb and the parameter. When you access to the codec
579on the slot 2 of the card 0, pass /dev/snd/hwC0D2 to the first
580argument, typically. (However, the real path name depends on the
581system.)
582
583The second parameter is the widget number-id to access. The third
584parameter can be either a hex/digit number or a string corresponding
585to a verb. Similarly, the last parameter is the value to write, or
586can be a string for the parameter type.
587
588------------------------------------------------------------------------
589 % hda-verb /dev/snd/hwC0D0 0x12 0x701 2
590 nid = 0x12, verb = 0x701, param = 0x2
591 value = 0x0
592
593 % hda-verb /dev/snd/hwC0D0 0x0 PARAMETERS VENDOR_ID
594 nid = 0x0, verb = 0xf00, param = 0x0
595 value = 0x10ec0262
596
597 % hda-verb /dev/snd/hwC0D0 2 set_a 0xb080
598 nid = 0x2, verb = 0x300, param = 0xb080
599 value = 0x0
600------------------------------------------------------------------------
601
602Although you can issue any verbs with this program, the driver state
603won't be always updated. For example, the volume values are usually
604cached in the driver, and thus changing the widget amp value directly
605via hda-verb won't change the mixer value.
606
607The hda-verb program is found in the ftp directory:
608
609- ftp://ftp.kernel.org/pub/linux/kernel/people/tiwai/misc/
610
611Also a git repository is available:
612
613- git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/hda-verb.git
614
615See README file in the tarball for more details about hda-verb
616program.
617
618
619hda-analyzer
620~~~~~~~~~~~~
621hda-analyzer provides a graphical interface to access the raw HD-audio
622control, based on pyGTK2 binding. It's a more powerful version of
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100623hda-verb. The program gives you an easy-to-use GUI stuff for showing
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100624the widget information and adjusting the amp values, as well as the
625proc-compatible output.
626
627The hda-analyzer is a part of alsa.git repository in
628alsa-project.org:
629
630- http://git.alsa-project.org/?p=alsa.git;a=tree;f=hda-analyzer
631
632
Takashi Iwai623b9f62008-12-11 07:44:18 +0100633Codecgraph
634~~~~~~~~~~
635Codecgraph is a utility program to generate a graph and visualizes the
636codec-node connection of a codec chip. It's especially useful when
637you analyze or debug a codec without a proper datasheet. The program
638parses the given codec proc file and converts to SVG via graphiz
639program.
640
641The tarball and GIT trees are found in the web page at:
642
643- http://helllabs.org/codecgraph/
644
645
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100646hda-emu
647~~~~~~~
Takashi Iwaid2afbe72008-12-10 09:28:15 +0100648hda-emu is an HD-audio emulator. The main purpose of this program is
Takashi Iwaia7fe49b2008-12-03 18:26:35 +0100649to debug an HD-audio codec without the real hardware. Thus, it
650doesn't emulate the behavior with the real audio I/O, but it just
651dumps the codec register changes and the ALSA-driver internal changes
652at probing and operating the HD-audio driver.
653
654The program requires a codec proc-file to simulate. Get a proc file
655for the target codec beforehand, or pick up an example codec from the
656codec proc collections in the tarball. Then, run the program with the
657proc file, and the hda-emu program will start parsing the codec file
658and simulates the HD-audio driver:
659
660------------------------------------------------------------------------
661 % hda-emu codecs/stac9200-dell-d820-laptop
662 # Parsing..
663 hda_codec: Unknown model for STAC9200, using BIOS defaults
664 hda_codec: pin nid 08 bios pin config 40c003fa
665 ....
666------------------------------------------------------------------------
667
668The program gives you only a very dumb command-line interface. You
669can get a proc-file dump at the current state, get a list of control
670(mixer) elements, set/get the control element value, simulate the PCM
671operation, the jack plugging simulation, etc.
672
673The package is found in:
674
675- ftp://ftp.kernel.org/pub/linux/kernel/people/tiwai/misc/
676
677A git repository is available:
678
679- git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/hda-emu.git
680
681See README file in the tarball for more details about hda-emu
682program.