This series implements: * Support for multiple rates in the audio gadget * Notification of gadget-side alsa processes about playback/capture start/stop on the host side via Playback/Capture Rate controls. * Detection of the USB cable disconnection by handling SUSPEND call in f_uac1/2. The disconnection generates a stop notification. Patches for the multirate support, originally authored by Julian Scheel, were rebased and modified for the current code base. Julian has acknowledged the presented patches. The detection of cable disconnection was discussed with dwc2 maintainer Minas Harutyunyan who confirmed that the suspend event can be used (https://lore.kernel.org/all/5aada8e3-f385-0589-8d58-187abd1a924d@xxxxxxxxxxxx/T/). Tests on dwc2 have confirmed reliable detection, the gadget correctly reports playback/capture stop at cable disconnection. The start/stop/current rate notification feature is accompanied by example implementation of audio gadget controller https://github.com/pavhofman/gaudio_ctl. The controller also handles debouncing fast start/stop events when USB host audio driver is loaded and/or audio daemon re/started. Changes: -------- v2: * Fixed compilation of "usb: gadget: f_uac1: Support multiple sampling rates" - added changes for CONFIG_GADGET_UAC1 v3: * Implemented most of changes suggested by John Keeping * Patches for bInterval calculation moved to a separate patch series * Patches for stopping substreams moved to a separate patch series * audio: Replaced deprecated macro S_IRUGO * u_audio: Moved dynamic srate from params to rtd * f_uac2: removed current state srates from struct f_uac2_opts, using u_audio_get_playback/capture_srate() instead. * f_uac2: Reworked macros for struct cntrl_ranges_lay3_xxx Julian Scheel (4): usb: gadget: u_audio: Support multiple sampling rates usb: gadget: f_uac2: Support multiple sampling rates usb: gadget: f_uac2: Rename Clock Sources to fixed names usb: gadget: f_uac1: Support multiple sampling rates Pavel Hofman (7): usb: gadget:audio: Replace deprecated macro S_IRUGO usb: gadget: u_audio: Move dynamic srate from params to rtd usb: gadget: u_audio: Add capture/playback srate getter usb: gadget: u_audio: Rate ctl notifies about current srate (0=stopped) usb: gadget: u_audio: Add suspend call usb: gadget: f_uac2: Add suspend callback usb: gadget: f_uac1: Add suspend callback .../ABI/testing/configfs-usb-gadget-uac1 | 4 +- .../ABI/testing/configfs-usb-gadget-uac2 | 4 +- Documentation/usb/gadget-testing.rst | 8 +- drivers/usb/gadget/function/f_uac1.c | 190 ++++++++++++-- drivers/usb/gadget/function/f_uac2.c | 209 ++++++++++++--- drivers/usb/gadget/function/u_audio.c | 238 ++++++++++++++++-- drivers/usb/gadget/function/u_audio.h | 14 +- drivers/usb/gadget/function/u_uac1.h | 5 +- drivers/usb/gadget/function/u_uac2.h | 5 +- drivers/usb/gadget/function/uac_common.h | 9 + drivers/usb/gadget/legacy/audio.c | 78 +++--- 11 files changed, 635 insertions(+), 129 deletions(-) create mode 100644 drivers/usb/gadget/function/uac_common.h -- 2.25.1
