diff --git a/src/class/audio/audio_device.c b/src/class/audio/audio_device.c index d9f2e284ed..a461e97c52 100644 --- a/src/class/audio/audio_device.c +++ b/src/class/audio/audio_device.c @@ -2248,12 +2248,13 @@ static void audiod_parse_for_AS_params(audiod_function_t* audio, uint8_t const * #if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP // Input value feedback has to be in 16.16 format - the format will be converted according to speed settings automatically +// unless format correction is disabled. bool tud_audio_n_fb_set(uint8_t func_id, uint32_t feedback) { TU_VERIFY(func_id < CFG_TUD_AUDIO && _audiod_fct[func_id].p_desc != NULL); // Format the feedback value -#if !TUD_OPT_HIGH_SPEED +#if !TUD_OPT_HIGH_SPEED && !CFG_TUD_AUDIO_DISABLE_FEEDBACK_FORMAT_CORRECTION uint8_t * fb = (uint8_t *) &_audiod_fct[func_id].fb_val; // For FS format is 10.14 diff --git a/src/class/audio/audio_device.h b/src/class/audio/audio_device.h index 5a469523c9..731fd6c018 100644 --- a/src/class/audio/audio_device.h +++ b/src/class/audio/audio_device.h @@ -186,6 +186,11 @@ #define CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP 0 // Feedback - 0 or 1 #endif +// Disable/enable conversion from 16.16 to 10.14 format on high-speed devices. See tud_audio_n_fb_set(). +#ifndef CFG_TUD_AUDIO_DISABLE_FEEDBACK_FORMAT_CORRECTION +#define CFG_TUD_AUDIO_DISABLE_FEEDBACK_FORMAT_CORRECTION 0 // 0 or 1 +#endif + // Audio interrupt control EP size - disabled if 0 #ifndef CFG_TUD_AUDIO_INT_CTR_EPSIZE_IN #define CFG_TUD_AUDIO_INT_CTR_EPSIZE_IN 0 // Audio interrupt control - if required - 6 Bytes according to UAC 2 specification (p. 74) @@ -458,6 +463,11 @@ TU_ATTR_WEAK bool tud_audio_fb_done_cb(uint8_t rhport); // Value will be corrected for FS to 10.14 format automatically. // (see Universal Serial Bus Specification Revision 2.0 5.12.4.2). // Feedback value will be sent at FB endpoint interval till it's changed. +// +// Note that the USB Audio 2.0 driver on Windows 10 is not following the spec and expects 16.16 +// format for FS. You can define CFG_TUD_AUDIO_DISABLE_FEEDBACK_FORMAT_CORRECTION=1 as a workaround +// to transmit the feedback value unchanged. Be aware that this might break feedback on other hosts, +// though at least on Linux the ALSA driver will happily accept either format. bool tud_audio_n_fb_set(uint8_t func_id, uint32_t feedback); static inline bool tud_audio_fb_set(uint32_t feedback); #endif