diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/class/audio/audio_host.c | 36 | ||||
| -rw-r--r-- | src/class/audio/audio_host.h | 6 |
2 files changed, 21 insertions, 21 deletions
diff --git a/src/class/audio/audio_host.c b/src/class/audio/audio_host.c index 8918ca86e..b682d2d8a 100644 --- a/src/class/audio/audio_host.c +++ b/src/class/audio/audio_host.c @@ -311,15 +311,12 @@ static tuh_audio_stream_t *audioh_find_stream(uint8_t dev_addr, uint8_t ep_addr) //--------------------------------------------------------------------+ // Re-arm the capture endpoint: request one full packet (the device sends at -// most its max packet size per poll interval). Only submit while the whole -// packet fits into the FIFO — otherwise the frame is lost anyway and the -// transfer would be wasted; the stream resumes when tuh_audio_read() frees -// FIFO space. +// most its max packet size per poll interval). The overwritable FIFO retains +// the newest capture frames when the application cannot drain it in time. static void audioh_stream_capture_xfer(tuh_audio_stream_t *s) { TU_VERIFY(s->state == STREAM_STATE_READY && s->running, ); const audioh_stream_map_t *map = &s->map[s->active_config]; - TU_VERIFY(tu_fifo_remaining(&s->edpt.ff) >= map->ep_size, ); TU_VERIFY(usbh_edpt_claim(s->daddr, map->ep_addr), ); // one transfer in flight // ep_size is guaranteed <= CFG_TUH_AUDIO_EPIN_BUFSIZE by enumeration @@ -347,13 +344,13 @@ static void audioh_stream_playback_xfer(tuh_audio_stream_t *s) { bytes_64 <= CFG_TUH_AUDIO_STREAM_BUFSIZE, ); const uint16_t bytes = (uint16_t)bytes_64; if (tu_fifo_count(&s->edpt.ff) < bytes) { - // Wait until one complete poll interval is queued. This is required when - // bInterval is greater than one frame and also avoids short audio packets. - usbh_edpt_release(s->daddr, map->ep_addr); - return; + // Keep the isochronous stream active without consuming a partial frame. + // The queued audio is sent once a complete poll interval is available. + tu_memclr(s->edpt.ep_buf, bytes); + } else { + tu_fifo_read_n(&s->edpt.ff, s->edpt.ep_buf, bytes); } - tu_fifo_read_n(&s->edpt.ff, s->edpt.ep_buf, bytes); TU_ASSERT(usbh_edpt_xfer(s->daddr, map->ep_addr, s->edpt.ep_buf, bytes), ); s->rem_acc = next_rem_acc; } @@ -506,7 +503,7 @@ bool audioh_init(void) { out->dir = TUSB_DIR_OUT; // Bind FIFO buffer and transfer buffer (see tu_edpt_stream_init) - TU_VERIFY(tu_edpt_stream_init(&in->edpt, true, false, false, in->ff_buf, CFG_TUH_AUDIO_STREAM_BUFSIZE, + TU_VERIFY(tu_edpt_stream_init(&in->edpt, true, false, true, in->ff_buf, CFG_TUH_AUDIO_STREAM_BUFSIZE, _audioh_epbuf[idx].epin)); TU_VERIFY(tu_edpt_stream_init(&out->edpt, true, true, false, out->ff_buf, CFG_TUH_AUDIO_STREAM_BUFSIZE, _audioh_epbuf[idx].epout)); @@ -883,8 +880,8 @@ uint16_t audioh_open(uint8_t rhport, uint8_t dev_addr, const tusb_desc_interface uint8_t usb_input_terminal_id = 0; uint8_t usb_output_source_id = 0; // A Feature Unit may precede the USB terminal that identifies its stream. - uint8_t pending_fu_id = 0; - uint8_t pending_fu_source_id = 0; + uint8_t pending_fu_id = 0; + uint8_t pending_fu_source_id = 0; bool have_header = false; p_desc = tu_desc_next(p_desc); @@ -1159,6 +1156,12 @@ bool tuh_audio_configure(uint8_t dev_idx, uint8_t stream_idx, uint8_t config_idx s->complete_cb = complete_cb; s->user_data = user_data; s->state = STREAM_STATE_CONFIG; + if (s->dir == TUSB_DIR_IN) { + // A byte FIFO can overwrite only complete audio frames when its depth is + // an exact multiple of the configured frame size. + const uint16_t fifo_depth = CFG_TUH_AUDIO_STREAM_BUFSIZE - (CFG_TUH_AUDIO_STREAM_BUFSIZE % s->frame_bytes); + TU_VERIFY(tu_fifo_config(&s->edpt.ff, s->ff_buf, fifo_depth, true), false); + } TU_LOG_DRV(" AUDIO configure %s stream %u: itf %u alt %u ep %02x\r\n", (s->dir == TUSB_DIR_IN) ? "capture" : "playback", s->stream_idx, map->itf_num, map->alt_setting, @@ -1187,7 +1190,7 @@ static void audioh_stream_start_complete(tuh_xfer_t *xfer) { if (s->dir == TUSB_DIR_IN) { audioh_stream_capture_xfer(s); // feed the capture endpoint } else { - audioh_stream_playback_xfer(s); // flush queued frames, if any + audioh_stream_playback_xfer(s); // start the continuous playback transfer chain } } @@ -1261,10 +1264,6 @@ uint32_t tuh_audio_write(uint8_t dev_idx, uint8_t stream_idx, const void *buffer } tu_fifo_write_n(&s->edpt.ff, buffer, (uint16_t)(frames * s->frame_bytes)); - // Flush a packet when the FIFO holds at least one; the scheduler drains - // the rest on completion - audioh_stream_playback_xfer(s); - return frames; } @@ -1283,7 +1282,6 @@ uint32_t tuh_audio_read(uint8_t dev_idx, uint8_t stream_idx, void *buffer, uint3 const uint32_t frames = TU_MIN(frame_count, tu_fifo_count(&s->edpt.ff) / s->frame_bytes); if (frames > 0) { tu_fifo_read_n(&s->edpt.ff, buffer, (uint16_t)(frames * s->frame_bytes)); - audioh_stream_capture_xfer(s); // re-arm: the FIFO has room again } return frames; } diff --git a/src/class/audio/audio_host.h b/src/class/audio/audio_host.h index 74dfdcdb6..9fcbe2577 100644 --- a/src/class/audio/audio_host.h +++ b/src/class/audio/audio_host.h @@ -45,7 +45,8 @@ extern "C" { // Depth in bytes of the per-stream data FIFO. The FIFO decouples the // application's read/write calls from the endpoint's isochronous polling cadence -// and absorbs rate differences. 1024 bytes hold 4 default (256 B) packets. +// and absorbs rate differences. Capture overwrites the oldest frames when full. +// 1024 bytes hold 4 default (256 B) packets. #ifndef CFG_TUH_AUDIO_STREAM_BUFSIZE #define CFG_TUH_AUDIO_STREAM_BUFSIZE 1024 #endif @@ -240,7 +241,8 @@ void tuh_audio_umount_cb(uint8_t idx); void tuh_audio_capture_cb(uint8_t idx, uint8_t stream_idx, uint16_t xferred_bytes); // Invoked when an isochronous OUT transfer completes successfully: the -// next queued packet is submitted from the stream's playback FIFO. +// next playback packet is submitted from the stream FIFO, or as silence when +// a complete packet is not queued. void tuh_audio_playback_cb(uint8_t idx, uint8_t stream_idx, uint16_t xferred_bytes); // Invoked when an isochronous transfer fails. The stream is stopped |