Hi guys, Any feedback on this patch series? Has anybody had a chance to test it? Regards, Ruslan On Tue, May 24, 2016 at 2:50 AM, Ruslan Bilovol <ruslan.bilovol@xxxxxxxxx> wrote: > I came to this patch series when wanted to do two things: > - use UAC1 as virtual ALSA sound card on gadget side, > just like UAC2 is used so it's possible to do rate > resampling > - have both playback/capture support in UAC1 > > Since I wanted to have same behavior for both UAC1/UAC2, > obviously I've got an utility part (u_audio.c) for > virtual ALSA sound card handling like we have > for ethernet(u_ether) or serial(u_serial) functions. > Function-specific parts (f_uac1/f_uac2) became almost > as storage for class-specfic USB descriptors, some > boilerplate for configfs, binding and few USB > config request handling. > > Major change to f_uac1 it that it can't do > direct play to existing ALSA sound card anymore, > representing audio on gadget side as virtual > ALSA sound card where audio streams are simply > sinked to and sourced from it, so it may break > current usecase for some people (and that's why > it's RFC). > > Luckily, it's possible to use existing user-space > applications for audio routing between Audio Gadget > and real sound card. I personally use alsaloop tool > from alsautils and have ability to create PCM > loopback between two different ALSA cards using > rate resampling, which is not possible with previous > "direct play to ALSA card" approach in f_uac1. > > While here, also dropped redundant platform > driver/device creation in f_uac2 driver as well as > "never implemented" volume/mute functionality in f_uac1 > that made this work even easier to do. > > This series is tested with both legacy g_audio.ko and > modern configfs approaches under Ubuntu 14.04 (UAC1 and > UAC2) and under Windows7 x64 (UAC1 only) having > perfect results in all cases. > > Some changes may have lack of good description that may > be obvious for me but not so clear for others, but I > hope to fix it in next versions. > > Comments, testing are welcome. > > Ruslan Bilovol (5): > usb: gadget: f_uac2: remove platform driver/device creation > usb: gadget: f_uac2: split out audio core > usb: gadget: f_uac1: drop volume/mute functionality > usb: gadget: f_uac1: switch to u_audio core utilities > usb: gadget: f_uac1: add capture support > > drivers/usb/gadget/Kconfig | 13 +- > drivers/usb/gadget/function/Makefile | 3 +- > drivers/usb/gadget/function/f_uac1.c | 842 +++++++++++++--------------------- > drivers/usb/gadget/function/f_uac2.c | 778 ++++--------------------------- > drivers/usb/gadget/function/u_audio.c | 632 +++++++++++++++++++++++++ > drivers/usb/gadget/function/u_audio.h | 93 ++++ > drivers/usb/gadget/function/u_uac1.c | 314 ------------- > drivers/usb/gadget/function/u_uac1.h | 71 +-- > drivers/usb/gadget/legacy/Kconfig | 1 + > drivers/usb/gadget/legacy/audio.c | 54 ++- > 10 files changed, 1208 insertions(+), 1593 deletions(-) > create mode 100644 drivers/usb/gadget/function/u_audio.c > create mode 100644 drivers/usb/gadget/function/u_audio.h > delete mode 100644 drivers/usb/gadget/function/u_uac1.c > > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
