diff --git a/examples/device/dynamic_configuration/src/main.c b/examples/device/dynamic_configuration/src/main.c index 3ad13aefa..45786e99a 100644 --- a/examples/device/dynamic_configuration/src/main.c +++ b/examples/device/dynamic_configuration/src/main.c @@ -165,6 +165,12 @@ void midi_task(void) { static uint32_t start_ms = 0; + // The MIDI interface always creates input and output port/jack descriptors + // regardless of these being used or not. Therefore incoming traffic should be read + // (possibly just discarded) to avoid the sender blocking in IO + uint8_t packet[4]; + while(tud_midi_available()) tud_midi_receive(packet); + // send note every 1000 ms if (board_millis() - start_ms < 286) return; // not enough time start_ms += 286; diff --git a/examples/device/midi_test/src/main.c b/examples/device/midi_test/src/main.c index 96292dd6b..d92621fc9 100644 --- a/examples/device/midi_test/src/main.c +++ b/examples/device/midi_test/src/main.c @@ -125,6 +125,12 @@ void midi_task(void) { static uint32_t start_ms = 0; + // The MIDI interface always creates input and output port/jack descriptors + // regardless of these being used or not. Therefore incoming traffic should be read + // (possibly just discarded) to avoid the sender blocking in IO + uint8_t packet[4]; + while(tud_midi_available()) tud_midi_receive(packet); + // send note every 1000 ms if (board_millis() - start_ms < 286) return; // not enough time start_ms += 286; diff --git a/src/class/midi/midi_device.c b/src/class/midi/midi_device.c index 9fff20be2..b9d6b2efc 100644 --- a/src/class/midi/midi_device.c +++ b/src/class/midi/midi_device.c @@ -85,6 +85,32 @@ bool tud_midi_n_mounted (uint8_t itf) return midi->ep_in && midi->ep_out; } +static void _prep_out_transaction (midid_interface_t* p_midi) +{ + uint8_t const rhport = TUD_OPT_RHPORT; + uint16_t available = tu_fifo_remaining(&p_midi->rx_ff); + + // Prepare for incoming data but only allow what we can store in the ring buffer. + // TODO Actually we can still carry out the transfer, keeping count of received bytes + // and slowly move it to the FIFO when read(). + // This pre-check reduces endpoint claiming + TU_VERIFY(available >= sizeof(p_midi->epout_buf), ); + + // claim endpoint + TU_VERIFY(usbd_edpt_claim(rhport, p_midi->ep_out), ); + + // fifo can be changed before endpoint is claimed + available = tu_fifo_remaining(&p_midi->rx_ff); + + if ( available >= sizeof(p_midi->epout_buf) ) { + usbd_edpt_xfer(rhport, p_midi->ep_out, p_midi->epout_buf, sizeof(p_midi->epout_buf)); + }else + { + // Release endpoint since we don't make any transfer + usbd_edpt_release(rhport, p_midi->ep_out); + } +} + //--------------------------------------------------------------------+ // READ API //--------------------------------------------------------------------+ @@ -135,12 +161,17 @@ uint32_t tud_midi_n_read(uint8_t itf, uint8_t jack_id, void* buffer, uint32_t bu void tud_midi_n_read_flush (uint8_t itf, uint8_t jack_id) { (void) jack_id; - tu_fifo_clear(&_midid_itf[itf].rx_ff); + midid_interface_t* p_midi = &_midid_itf[itf]; + tu_fifo_clear(&p_midi->rx_ff); + _prep_out_transaction(p_midi); } bool tud_midi_n_receive (uint8_t itf, uint8_t packet[4]) { - return tu_fifo_read_n(&_midid_itf[itf].rx_ff, packet, 4); + midid_interface_t* p_midi = &_midid_itf[itf]; + uint32_t num_read = tu_fifo_read_n(&p_midi->rx_ff, packet, 4); + _prep_out_transaction(p_midi); + return (num_read == 4); } void midi_rx_done_cb(midid_interface_t* midi, uint8_t const* buffer, uint32_t bufsize) { @@ -275,8 +306,8 @@ void midid_init(void) midid_interface_t* midi = &_midid_itf[i]; // config fifo - tu_fifo_config(&midi->rx_ff, midi->rx_ff_buf, CFG_TUD_MIDI_RX_BUFSIZE, 1, true); - tu_fifo_config(&midi->tx_ff, midi->tx_ff_buf, CFG_TUD_MIDI_TX_BUFSIZE, 1, true); + tu_fifo_config(&midi->rx_ff, midi->rx_ff_buf, CFG_TUD_MIDI_RX_BUFSIZE, 1, false); // true, true + tu_fifo_config(&midi->tx_ff, midi->tx_ff_buf, CFG_TUD_MIDI_TX_BUFSIZE, 1, false); // OBVS. #if CFG_FIFO_MUTEX tu_fifo_config_mutex(&midi->rx_ff, osal_mutex_create(&midi->rx_ff_mutex)); @@ -367,11 +398,7 @@ uint16_t midid_open(uint8_t rhport, tusb_desc_interface_t const * desc_itf, uint } // Prepare for incoming data - if ( !usbd_edpt_xfer(rhport, p_midi->ep_out, p_midi->epout_buf, CFG_TUD_MIDI_EP_BUFSIZE) ) - { - TU_LOG1_FAILED(); - TU_BREAKPOINT(); - } + _prep_out_transaction(p_midi); return drv_len; } @@ -392,6 +419,7 @@ bool midid_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_request_t bool midid_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_t xferred_bytes) { (void) result; + (void) rhport; uint8_t itf; midid_interface_t* p_midi; @@ -415,7 +443,7 @@ bool midid_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32 // prepare for next // TODO for now ep_out is not used by public API therefore there is no race condition, // and does not need to claim like ep_in - TU_ASSERT(usbd_edpt_xfer(rhport, p_midi->ep_out, p_midi->epout_buf, CFG_TUD_MIDI_EP_BUFSIZE), false); + _prep_out_transaction(p_midi); } else if ( ep_addr == p_midi->ep_in ) {