kernel/drivers/usb/gadget/function/u_uac2.h, branch linux-6.9.y

usb: gadget: f_uac2: allow changing terminal types through configfs

2023-10-05T07:35:43Z

Add "c_terminal_type" and "p_terminal_type" configfs entries in order to allow the user to change the capture and playback terminal type codes. These fields affect the type of audio device that Windows detects, so being able to modify this is useful when it would be advantageous for a gadget to be detected as something other than a generic speaker/microphone. The fields default to microphone for the capture type field and speaker for the playback type field as was the case before. Signed-off-by: James Gruber Link: https://lore.kernel.org/r/20230914222746.155126-1-jimmyjgruber@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: Optionally determine bInterval for HS and SS

2022-01-31T13:26:18Z

Allow setting configfs params p_hs_bint/c_hs_bint to 0. If they are set to 0, determine the largest bInterval (4 to 1) for which the required bandwidth of the max samplerate fits the max allowed packet size. If the required bandwidth exceeds max bandwidth for single-packet mode (ep->mc=1), keep bInterval at 1. The FS speed is left at fixed bInterval=1. If for any speed the required bandwidth exceeds the max bandwidth corresponding to the selected/determined bInterval, print a warning. Signed-off-by: Pavel Hofman Link: https://lore.kernel.org/r/20220127114331.41367-4-pavel.hofman@ivitera.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: Add HS/SS bInterval to configfs

2022-01-31T13:26:18Z

Allow configuring the HS/SS bInterval through configfs, via parameters p_hs_bint/c_hs_bint separately for playback/capture. The default param values are left at the original 4. Suggested-by: John Keeping Signed-off-by: Pavel Hofman Link: https://lore.kernel.org/r/20220127114331.41367-2-pavel.hofman@ivitera.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: allow changing interface name via configfs

2022-01-26T13:10:44Z

This adds "function_name" configfs entry to change string value of the iInterface field. This field will be shown in Windows' audio settings panel, so being able to change it is useful. It will default to "Source/Sink" just as before. Signed-off-by: Yunhao Tian Link: https://lore.kernel.org/r/20220122112446.1415547-2-t123yh.xyz@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: Support multiple sampling rates

2022-01-26T13:06:08Z

A list of sampling rates can be specified via configfs. All enabled sampling rates are sent to the USB host on request. When the host selects a sampling rate, the internal active rate (stored in struct f_uac2) is updated. The gadget no longer supports only one frequency. Therefore USB strings corresponding to the clock sources are renamed from specific Hz value to general names Input clock/Output clock. Config strings with single value stay compatible with the previous version. Multiple samplerates passed as configuration arrays to g_audio module when built for f_uac2. Signed-off-by: Julian Scheel Signed-off-by: Pavel Hofman Link: https://lore.kernel.org/r/20220121155308.48794-6-pavel.hofman@ivitera.com Signed-off-by: Greg Kroah-Hartman

usb:gadget: f_uac1: fixed sync playback

2021-10-25T07:19:21Z

The u_audio param fb_max was not set to its default value in f_uac1.c. As a result the maximum value of Playback Pitch ctl was kept at 1000000, not allowing to set faster playback pitch for UAC1. The setting required moving the default constant UAC2_DEF_FB_MAX from u_uac2.h to FBACK_FAST_MAX in u_audio.h as that header is common for f_uac1.c and f_uac2.c. Fixes: 6fec018a7e70 ("usb: gadget: u_audio.c: Adding Playback Pitch ctl for sync playback") Signed-off-by: Pavel Hofman Link: https://lore.kernel.org/r/20211022140339.248669-1-pavel.hofman@ivitera.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: add volume and mute support

2021-07-21T08:10:11Z

This adds bi-directional (host->device, device->host) volume/mute support to the f_uac2 driver by adding Feature Units and interrupt endpoint. Currently only master channel is supported. Volume and mute are configurable through configfs, by default volume has -100..0 dB range with 1 dB step. Similar to existing flexible endpoints configuration, Feature Unit won't be added to the topology if both mute and volume are not enabled, also interrupt endpoint isn't added to the device if no feature unit is present Signed-off-by: Ruslan Bilovol Signed-off-by: Pavel Hofman Link: https://lore.kernel.org/r/20210712125529.76070-4-pavel.hofman@ivitera.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: add real feedback implementation

2021-06-09T09:26:49Z

This adds interface between userspace and feedback endpoint to report real feedback frequency to the Host. Current implementation adds new userspace interface ALSA mixer control "Capture Pitch 1000000" (similar to aloop driver's "PCM Rate Shift 100000" mixer control) Value in PPM is chosen to have correction value agnostic of the actual HW rate, which the application is not necessarily dealing with, while still retaining a good enough precision to allow smooth clock correction on the playback side, if necessary. Similar to sound/usb/endpoint.c, a slow down is allowed up to 25%. This has no impact on the required bandwidth. Speedup correction has an impact on the bandwidth reserved for the isochronous endpoint. The default allowed speedup is 500ppm. This seems to be more than enough but, if necessary, this is configurable through a module parameter. The reserved bandwidth is rounded up to the next packet size. Usage of this new control is easy to implement in existing userspace tools like alsaloop from alsa-utils. Signed-off-by: Ruslan Bilovol Signed-off-by: Jerome Brunet Link: https://lore.kernel.org/r/20210603220104.1216001-4-jbrunet@baylibre.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: add adaptive sync support for capture

2021-06-09T09:26:49Z

Current f_uac2 USB OUT (aka 'capture') synchronization implements 'ASYNC' scenario which means USB Gadget has it's own freerunning clock and can update Host about real clock frequency through feedback endpoint so Host can align number of samples sent to the USB gadget to prevent overruns/underruns In case if Gadget can has no it's internal clock and can consume audio samples at any rate (for example, on the Gadget side someone records audio directly to a file, or audio samples are played through an external DAC as soon as they arrive), UAC2 spec suggests 'ADAPTIVE' synchronization type. Change UAC2 driver to make it configurable through additional 'c_sync' configfs file. Default remains 'asynchronous' with possibility to switch it to 'adaptive' Signed-off-by: Ruslan Bilovol Signed-off-by: Jerome Brunet Link: https://lore.kernel.org/r/20210603220104.1216001-3-jbrunet@baylibre.com Signed-off-by: Greg Kroah-Hartman

USB: gadget: Use the correct style for SPDX License Identifier

2020-05-05T07:58:49Z

This patch corrects the SPDX License Identifier style in header files related to USB peripheral controller drivers. For C header files Documentation/process/license-rules.rst mandates C-like comments (opposed to C source files where C++ style should be used). Changes made by using a script provided by Joe Perches here: https://lkml.org/lkml/2019/2/7/46. Suggested-by: Joe Perches Signed-off-by: Nishad Kamdar Signed-off-by: Felipe Balbi