diff options
Diffstat (limited to 'Documentation/sound/alsa-configuration.rst')
| -rw-r--r-- | Documentation/sound/alsa-configuration.rst | 147 |
1 files changed, 115 insertions, 32 deletions
diff --git a/Documentation/sound/alsa-configuration.rst b/Documentation/sound/alsa-configuration.rst index 34888d4fc4a8..0a4eaa7d66dd 100644 --- a/Documentation/sound/alsa-configuration.rst +++ b/Documentation/sound/alsa-configuration.rst @@ -58,7 +58,7 @@ debug 2 = verbose debug messages); This option appears only when ``CONFIG_SND_DEBUG=y``. This option can be dynamically changed via sysfs - /sys/modules/snd/parameters/debug file. + /sys/module/snd/parameters/debug file. Module snd-pcm-oss ------------------ @@ -70,7 +70,7 @@ dsp_map PCM device number maps assigned to the 1st OSS device; Default: 0 adsp_map - PCM device number maps assigned to the 2st OSS device; + PCM device number maps assigned to the 2nd OSS device; Default: 1 nonblock_open Don't block opening busy PCM devices; @@ -97,7 +97,7 @@ midi_map MIDI device number maps assigned to the 1st OSS device; Default: 0 amidi_map - MIDI device number maps assigned to the 2st OSS device; + MIDI device number maps assigned to the 2nd OSS device; Default: 1 Module snd-soc-core @@ -133,6 +133,19 @@ enable enable card; Default: enabled, for PCI and ISA PnP cards +These options are used for either specifying the order of instances or +controlling enabling and disabling of each one of the devices if there +are multiple devices bound with the same driver. For example, there are +many machines which have two HD-audio controllers (one for HDMI/DP +audio and another for onboard analog). In most cases, the second one is +in primary usage, and people would like to assign it as the first +appearing card. They can do it by specifying "index=1,0" module +parameter, which will swap the assignment slots. + +Today, with the sound backend like PulseAudio and PipeWire which +supports dynamic configuration, it's of little use, but that was a +help for static configuration in the past. + Module snd-adlib ---------------- @@ -723,13 +736,14 @@ Module for EMU10K1/EMU10k2 based PCI sound cards. * Sound Blaster Live! * Sound Blaster PCI 512 -* Emu APS (partially supported) * Sound Blaster Audigy - +* E-MU APS (partially supported) +* E-MU DAS + extin - bitmap of available external inputs for FX8010 (see bellow) + bitmap of available external inputs for FX8010 (see below) extout - bitmap of available external outputs for FX8010 (see bellow) + bitmap of available external outputs for FX8010 (see below) seq_ports allocated sequencer ports (4 by default) max_synth_voices @@ -1045,6 +1059,9 @@ power_save Automatic power-saving timeout (in second, 0 = disable) power_save_controller Reset HD-audio controller in power-saving mode (default = on) +pm_blacklist + Enable / disable power-management deny-list (default = look up PM + deny-list, 0 = skip PM deny-list, 1 = force to turn off runtime PM) align_buffer_size Force rounding of buffer/period sizes to multiples of 128 bytes. This is more efficient in terms of memory access but isn't @@ -2236,8 +2253,15 @@ device_setup Default: 0x0000 ignore_ctl_error Ignore any USB-controller regarding mixer interface (default: no) + ``ignore_ctl_error=1`` may help when you get an error at accessing + the mixer element such as URB error -22. This happens on some + buggy USB device or the controller. This workaround corresponds to + the ``quirk_flags`` bit 14, too. autoclock Enable auto-clock selection for UAC2 devices (default: yes) +lowlatency + Enable low latency playback mode (default: yes). + Could disable it to switch back to the old mode if face a regression. quirk_alias Quirk alias list, pass strings like ``0123abcd:5678beef``, which applies the existing quirk for the device 5678:beef to a new @@ -2246,7 +2270,7 @@ implicit_fb Apply the generic implicit feedback sync mode. When this is set and the playback stream sync mode is ASYNC, the driver tries to tie an adjacent ASYNC capture stream as the implicit feedback - source. + source. This is equivalent with quirk_flags bit 17. use_vmalloc Use vmalloc() for allocations of the PCM buffers (default: yes). For architectures with non-coherent memory like ARM or MIPS, the @@ -2267,27 +2291,87 @@ delayed_register The driver prints a message like "Found post-registration device assignment: 1234abcd:04" for such a device, so that user can notice the need. +skip_validation + Skip unit descriptor validation (default: no). + The option is used to ignore the validation errors with the hexdump + of the unit descriptor instead of a driver probe error, so that we + can check its details. quirk_flags - Contains the bit flags for various device specific workarounds. - Applied to the corresponding card index. - - * bit 0: Skip reading sample rate for devices - * bit 1: Create Media Controller API entries - * bit 2: Allow alignment on audio sub-slot at transfer - * bit 3: Add length specifier to transfers - * bit 4: Start playback stream at first in implement feedback mode - * bit 5: Skip clock selector setup - * bit 6: Ignore errors from clock source search - * bit 7: Indicates ITF-USB DSD based DACs - * bit 8: Add a delay of 20ms at each control message handling - * bit 9: Add a delay of 1-2ms at each control message handling - * bit 10: Add a delay of 5-6ms at each control message handling - * bit 11: Add a delay of 50ms at each interface setup - * bit 12: Perform sample rate validations at probe - * bit 13: Disable runtime PM autosuspend - * bit 14: Ignore errors for mixer access - * bit 15: Support generic DSD raw U32_BE format - * bit 16: Set up the interface at first like UAC1 + The option provides a refined and flexible control for applying quirk + flags. It allows to specify the quirk flags for each device, and can + be modified dynamically via sysfs. + The old usage accepts an array of integers, each of which applies quirk + flags on the device in the order of probing. + E.g., ``quirk_flags=0x01,0x02`` applies get_sample_rate to the first + device, and share_media_device to the second device. + The new usage accepts a string in the format of + ``VID1:PID1:FLAGS1;VID2:PID2:FLAGS2;...``, where ``VIDx`` and ``PIDx`` + specify the device, and ``FLAGSx`` specify the flags to be applied. + ``VIDx`` and ``PIDx`` are 4-digit hexadecimal numbers, and can be + specified as ``*`` to match any value. ``FLAGSx`` can be a set of + flags given by name, separated by ``|``, or a hexadecimal number + representing the bit flags. The available flag names are listed below. + An exclamation mark can be prefixed to a flag name to negate the flag. + For example, ``1234:abcd:mixer_playback_min_mute|!ignore_ctl_error;*:*:0x01;`` + applies the ``mixer_playback_min_mute`` flag and clears the + ``ignore_ctl_error`` flag for the device 1234:abcd, and applies the + ``skip_sample_rate`` flag for all devices. + + * bit 0: ``get_sample_rate`` + Skip reading sample rate for devices + * bit 1: ``share_media_device`` + Create Media Controller API entries + * bit 2: ``align_transfer`` + Allow alignment on audio sub-slot at transfer + * bit 3: ``tx_length`` + Add length specifier to transfers + * bit 4: ``playback_first`` + Start playback stream at first in implement feedback mode + * bit 5: ``skip_clock_selector`` + Skip clock selector setup + * bit 6: ``ignore_clock_source`` + Ignore errors from clock source search + * bit 7: ``itf_usb_dsd_dac`` + Indicates ITF-USB DSD-based DACs + * bit 8: ``ctl_msg_delay`` + Add a delay of 20ms at each control message handling + * bit 9: ``ctl_msg_delay_1m`` + Add a delay of 1-2ms at each control message handling + * bit 10: ``ctl_msg_delay_5m`` + Add a delay of 5-6ms at each control message handling + * bit 11: ``iface_delay`` + Add a delay of 50ms at each interface setup + * bit 12: ``validate_rates`` + Perform sample rate validations at probe + * bit 13: ``disable_autosuspend`` + Disable runtime PM autosuspend + * bit 14: ``ignore_ctl_error`` + Ignore errors for mixer access + * bit 15: ``dsd_raw`` + Support generic DSD raw U32_BE format + * bit 16: ``set_iface_first`` + Set up the interface at first like UAC1 + * bit 17: ``generic_implicit_fb`` + Apply the generic implicit feedback sync mode + * bit 18: ``skip_implicit_fb`` + Don't apply implicit feedback sync mode + * bit 19: ``iface_skip_close`` + Don't close interface during setting sample rate + * bit 20: ``force_iface_reset`` + Force an interface reset whenever stopping & restarting a stream + * bit 21: ``fixed_rate`` + Do not set PCM rate (frequency) when only one rate is available + for the given endpoint + * bit 22: ``mic_res_16`` + Set the fixed resolution 16 for Mic Capture Volume + * bit 23: ``mic_res_384`` + Set the fixed resolution 384 for Mic Capture Volume + * bit 24: ``mixer_playback_min_mute`` + Set minimum volume control value as mute for devices where the + lowest playback value represents muted state instead of minimum + audible volume + * bit 25: ``mixer_capture_min_mute`` + Similar to bit 24 but for capture streams This module supports multiple devices, autoprobe and hotplugging. @@ -2295,10 +2379,9 @@ NB: ``nrpacks`` parameter can be modified dynamically via sysfs. Don't put the value over 20. Changing via sysfs has no sanity check. -NB: ``ignore_ctl_error=1`` may help when you get an error at accessing -the mixer element such as URB error -22. This happens on some -buggy USB device or the controller. This workaround corresponds to -the ``quirk_flags`` bit 14, too. +NB: ``ignore_ctl_error=1`` just provides a quick way to work around the +issues. If you have a buggy device that requires these quirks, please +report it to the upstream. NB: ``quirk_alias`` option is provided only for testing / development. If you want to have a proper support, contact to upstream for |