From 1b66c148cce2699c3f5e470fa82f0efb192eb00a Mon Sep 17 00:00:00 2001 From: HiFiPhile Date: Sun, 19 Nov 2023 15:55:24 +0100 Subject: [PATCH] UAC2: Implement feedback by fifo counting. --- src/class/audio/audio_device.c | 169 ++++++++++++++++++++++----------- src/class/audio/audio_device.h | 11 +-- 2 files changed, 114 insertions(+), 66 deletions(-) diff --git a/src/class/audio/audio_device.c b/src/class/audio/audio_device.c index 9ba38a20c..4ca95d4e7 100644 --- a/src/class/audio/audio_device.c +++ b/src/class/audio/audio_device.c @@ -2,6 +2,7 @@ * The MIT License (MIT) * * Copyright (c) 2020 Reinhard Panhuber, Jerzy Kasenberg + * Copyright (c) 2023 HiFiPhile * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -319,7 +320,8 @@ typedef struct #if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP struct { - CFG_TUSB_MEM_ALIGN uint32_t value; // Feedback value for asynchronous mode (in 16.16 format). + CFG_TUSB_MEM_ALIGN uint32_t send_buf; + uint32_t value; // Feedback value for asynchronous mode (in 16.16 format). uint32_t min_value; // min value according to UAC2 FMT-2.0 section 2.3.1.1. uint32_t max_value; // max value according to UAC2 FMT-2.0 section 2.3.1.1. @@ -335,12 +337,12 @@ typedef struct uint32_t mclk_freq; }fixed; -#if 0 // implement later struct { - uint32_t nominal_value; - uint32_t threshold_bytes; + uint32_t nom_value; // In 16.16 format + uint32_t fifo_lvl_avg; // In 16.16 format + uint16_t fifo_lvl_thr; // fifo level threshold + uint16_t rate_const[2]; // pre-computed feedback/fifo_depth rate }fifo_count; -#endif }compute; } feedback; @@ -473,7 +475,8 @@ static uint16_t audiod_tx_packet_size(const uint16_t* norminal_size, uint16_t da #endif #if CFG_TUD_AUDIO_ENABLE_EP_OUT && CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP -static bool set_fb_params_freq(audiod_function_t* audio, uint32_t sample_freq, uint32_t mclk_freq); +static bool audiod_set_fb_params_freq(audiod_function_t* audio, uint32_t sample_freq, uint32_t mclk_freq); +static void audiod_fb_fifo_count_update(audiod_function_t* audio, uint16_t lvl_new); #endif bool tud_audio_n_mounted(uint8_t func_id) @@ -566,7 +569,7 @@ static bool audiod_rx_done_cb(uint8_t rhport, audiod_function_t* audio, uint16_t TU_VERIFY(tud_audio_rx_done_pre_read_cb(rhport, n_bytes_received, idx_audio_fct, audio->ep_out, audio->alt_setting[idxItf])); } -#if CFG_TUD_AUDIO_ENABLE_DECODING && CFG_TUD_AUDIO_ENABLE_EP_OUT +#if CFG_TUD_AUDIO_ENABLE_DECODING switch (audio->format_type_rx) { @@ -615,6 +618,13 @@ static bool audiod_rx_done_cb(uint8_t rhport, audiod_function_t* audio, uint16_t TU_VERIFY(usbd_edpt_xfer_fifo(rhport, audio->ep_out, &audio->ep_out_ff, audio->ep_out_sz), false); #endif +#if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP + if(audio->feedback.compute_method == AUDIO_FEEDBACK_METHOD_FIFO_COUNT) + { + audiod_fb_fifo_count_update(audio, tu_fifo_count(&audio->ep_out_ff)); + } +#endif + #endif // Call a weak callback here - a possibility for user to get informed decoding was completed @@ -725,6 +735,13 @@ static bool audiod_decode_type_I_pcm(uint8_t rhport, audiod_function_t* audio, u // Number of bytes should be a multiple of CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_RX * CFG_TUD_AUDIO_N_CHANNELS_RX but checking makes no sense - no way to correct it // TU_VERIFY(cnt != n_bytes); +#if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP + if(audio->feedback.compute_method == AUDIO_FEEDBACK_METHOD_FIFO_COUNT) + { + audiod_fb_fifo_count_update(audio, tu_fifo_count(&audio->rx_supp_ff[0])); + } +#endif + return true; } #endif //CFG_TUD_AUDIO_ENABLE_DECODING @@ -1067,9 +1084,29 @@ static uint16_t audiod_encode_type_I_pcm(uint8_t rhport, audiod_function_t* audi // This function is called once a transmit of a feedback packet was successfully completed. Here, we get the next feedback value to be sent #if CFG_TUD_AUDIO_ENABLE_EP_OUT && CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP -static inline bool audiod_fb_send(uint8_t rhport, audiod_function_t *audio) +static inline bool audiod_fb_send(audiod_function_t *audio) { - return usbd_edpt_xfer(rhport, audio->ep_fb, (uint8_t *) &audio->feedback.value, 4); + // Format the feedback value +#if CFG_TUD_AUDIO_ENABLE_FEEDBACK_FORMAT_CORRECTION + if ( TUSB_SPEED_FULL == tud_speed_get() ) + { + uint8_t * fb = (uint8_t *) &audio->feedback.send_buf; + + // For FS format is 10.14 + *(fb++) = (audio->feedback.value >> 2) & 0xFF; + *(fb++) = (audio->feedback.value >> 10) & 0xFF; + *(fb++) = (audio->feedback.value >> 18) & 0xFF; + // 4th byte is needed to work correctly with MS Windows + *fb = 0; + } else + { + value = audio->feedback.value; + } +#else + audio->feedback.send_buf = audio->feedback.value; +#endif + + return usbd_edpt_xfer(audio->rhport, audio->ep_fb, (uint8_t *) &audio->feedback.send_buf, 4); } #endif @@ -1861,7 +1898,7 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const * // Minimal/Maximum value in 16.16 format for full speed (1ms per frame) or high speed (125 us per frame) uint32_t const frame_div = (TUSB_SPEED_FULL == tud_speed_get()) ? 1000 : 8000; - audio->feedback.min_value = (fb_param.sample_freq/frame_div - 1) << 16; + audio->feedback.min_value = ((fb_param.sample_freq - 1)/frame_div) << 16; audio->feedback.max_value = (fb_param.sample_freq/frame_div + 1) << 16; switch(fb_param.method) @@ -1869,20 +1906,27 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const * case AUDIO_FEEDBACK_METHOD_FREQUENCY_FIXED: case AUDIO_FEEDBACK_METHOD_FREQUENCY_FLOAT: case AUDIO_FEEDBACK_METHOD_FREQUENCY_POWER_OF_2: - set_fb_params_freq(audio, fb_param.sample_freq, fb_param.frequency.mclk_freq); + audiod_set_fb_params_freq(audio, fb_param.sample_freq, fb_param.frequency.mclk_freq); break; - #if 0 // implement later case AUDIO_FEEDBACK_METHOD_FIFO_COUNT: { - uint64_t fb64 = ((uint64_t) fb_param.sample_freq) << 16; - audio->feedback.compute.fifo_count.nominal_value = (uint32_t) (fb64 / frame_div); - audio->feedback.compute.fifo_count.threshold_bytes = fb_param.fifo_count.threshold_bytes; - - tud_audio_fb_set(audio->feedback.compute.fifo_count.nominal_value); + /* Initialize the threshold level to half filled */ + uint16_t fifo_lvl_thr; +#if CFG_TUD_AUDIO_ENABLE_DECODING + fifo_lvl_thr = tu_fifo_depth(&audio->rx_supp_ff[0]) / 2; +#else + fifo_lvl_thr = tu_fifo_depth(&audio->ep_out_ff) / 2; +#endif + audio->feedback.compute.fifo_count.fifo_lvl_thr = fifo_lvl_thr; + audio->feedback.compute.fifo_count.fifo_lvl_avg = ((uint32_t)fifo_lvl_thr) << 16; + /* Avoid 64bit division */ + uint32_t nominal = ((fb_param.sample_freq / 100) << 16) / (frame_div / 100); + audio->feedback.compute.fifo_count.nom_value = nominal; + audio->feedback.compute.fifo_count.rate_const[0] = (audio->feedback.max_value - nominal) / fifo_lvl_thr; + audio->feedback.compute.fifo_count.rate_const[1] = (nominal - audio->feedback.min_value) / fifo_lvl_thr; } break; - #endif // nothing to do default: break; @@ -2198,7 +2242,7 @@ bool audiod_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint3 if (!usbd_edpt_busy(rhport, audio->ep_fb)) { // Schedule next transmission - value is changed bytud_audio_n_fb_set() in the meantime or the old value gets sent - return audiod_fb_send(rhport, audio); + return audiod_fb_send(audio); } } #endif @@ -2210,7 +2254,7 @@ bool audiod_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint3 #if CFG_TUD_AUDIO_ENABLE_EP_OUT && CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP -static bool set_fb_params_freq(audiod_function_t* audio, uint32_t sample_freq, uint32_t mclk_freq) +static bool audiod_set_fb_params_freq(audiod_function_t* audio, uint32_t sample_freq, uint32_t mclk_freq) { // Check if frame interval is within sane limits // The interval value n_frames was taken from the descriptors within audiod_set_interface() @@ -2244,6 +2288,38 @@ static bool set_fb_params_freq(audiod_function_t* audio, uint32_t sample_freq, u return true; } +static void audiod_fb_fifo_count_update(audiod_function_t* audio, uint16_t lvl_new) +{ + /* Low-pass (averaging) filter */ + uint32_t lvl = audio->feedback.compute.fifo_count.fifo_lvl_avg; + lvl = (uint32_t)(((uint64_t)lvl * 63 + ((uint32_t)lvl_new << 16)) >> 6); + audio->feedback.compute.fifo_count.fifo_lvl_avg = lvl; + + uint32_t const ff_lvl = lvl >> 16; + uint16_t const ff_thr = audio->feedback.compute.fifo_count.fifo_lvl_thr; + uint16_t const *rate = audio->feedback.compute.fifo_count.rate_const; + + uint32_t feedback; + + if(ff_lvl < ff_thr) + { + feedback = audio->feedback.compute.fifo_count.nom_value + (ff_thr - ff_lvl) * rate[0]; + } else + { + feedback = audio->feedback.compute.fifo_count.nom_value - (ff_lvl - ff_thr) * rate[1]; + } + + if ( feedback > audio->feedback.max_value ) feedback = audio->feedback.max_value; + if ( feedback < audio->feedback.min_value ) feedback = audio->feedback.min_value; + audio->feedback.value = feedback; + + // Schedule a transmit with the new value if EP is not busy - this triggers repetitive scheduling of the feedback value + if (!usbd_edpt_busy(audio->rhport, audio->ep_fb)) + { + audiod_fb_send(audio); + } +} + uint32_t tud_audio_feedback_update(uint8_t func_id, uint32_t cycles) { audiod_function_t* audio = &_audiod_fct[func_id]; @@ -2280,6 +2356,21 @@ uint32_t tud_audio_feedback_update(uint8_t func_id, uint32_t cycles) return feedback; } + +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); + + _audiod_fct[func_id].feedback.value = feedback; + + // Schedule a transmit with the new value if EP is not busy - this triggers repetitive scheduling of the feedback value + if (!usbd_edpt_busy(_audiod_fct[func_id].rhport, _audiod_fct[func_id].ep_fb)) + { + return audiod_fb_send(&_audiod_fct[func_id]); + } + + return true; +} #endif TU_ATTR_FAST_FUNC void audiod_sof_isr (uint8_t rhport, uint32_t frame_count) @@ -2691,44 +2782,8 @@ static uint16_t audiod_tx_packet_size(const uint16_t* norminal_size, uint16_t da #endif -#if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP - -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 CFG_TUD_AUDIO_ENABLE_FEEDBACK_FORMAT_CORRECTION - if ( TUSB_SPEED_FULL == tud_speed_get() ) - { - uint8_t * fb = (uint8_t *) &_audiod_fct[func_id].feedback.value; - - // For FS format is 10.14 - *(fb++) = (feedback >> 2) & 0xFF; - *(fb++) = (feedback >> 10) & 0xFF; - *(fb++) = (feedback >> 18) & 0xFF; - // 4th byte is needed to work correctly with MS Windows - *fb = 0; - }else -#else - { - // Send value as-is, caller will choose the appropriate format - _audiod_fct[func_id].feedback.value = feedback; - } -#endif - - // Schedule a transmit with the new value if EP is not busy - this triggers repetitive scheduling of the feedback value - if (!usbd_edpt_busy(_audiod_fct[func_id].rhport, _audiod_fct[func_id].ep_fb)) - { - return audiod_fb_send(_audiod_fct[func_id].rhport, &_audiod_fct[func_id]); - } - - return true; -} -#endif - // No security checks here - internal function only which should always succeed -uint8_t audiod_get_audio_fct_idx(audiod_function_t * audio) +static uint8_t audiod_get_audio_fct_idx(audiod_function_t * audio) { for (uint8_t cnt=0; cnt < CFG_TUD_AUDIO; cnt++) { diff --git a/src/class/audio/audio_device.h b/src/class/audio/audio_device.h index b16514fd4..9c95ce1a9 100644 --- a/src/class/audio/audio_device.h +++ b/src/class/audio/audio_device.h @@ -3,6 +3,7 @@ * * Copyright (c) 2020 Ha Thach (tinyusb.org) * Copyright (c) 2020 Reinhard Panhuber + * Copyright (c) 2023 HiFiPhile * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -487,7 +488,6 @@ TU_ATTR_WEAK void tud_audio_fb_done_cb(uint8_t func_id); // feedback = n_cycles / n_frames * f_s / f_m in 16.16 format, where n_cycles are the number of main clock cycles within fb_n_frames bool tud_audio_n_fb_set(uint8_t func_id, uint32_t feedback); -static inline bool tud_audio_fb_set(uint32_t feedback); // Update feedback value with passed cycles since last time this update function is called. // Typically called within tud_audio_sof_isr(). Required tud_audio_feedback_params_cb() is implemented @@ -500,9 +500,7 @@ enum { AUDIO_FEEDBACK_METHOD_FREQUENCY_FIXED, AUDIO_FEEDBACK_METHOD_FREQUENCY_FLOAT, AUDIO_FEEDBACK_METHOD_FREQUENCY_POWER_OF_2, - - // impelemnt later - // AUDIO_FEEDBACK_METHOD_FIFO_COUNT + AUDIO_FEEDBACK_METHOD_FIFO_COUNT }; typedef struct { @@ -514,11 +512,6 @@ typedef struct { uint32_t mclk_freq; // Main clock frequency in Hz i.e. master clock to which sample clock is based on }frequency; -#if 0 // implement later - struct { - uint32_t threshold_bytes; // minimum number of bytes received to be considered as filled/ready - }fifo_count; -#endif }; }audio_feedback_params_t;