shared/tinyusb: Add common cdc tx/rx functions.

Signed-off-by: Andrew Leech <andrew@alelec.net>

shared/tinyusb/mp_cdc_common.c

@@ -28,9 +28,87 @@
 #include "py/mphal.h"
 #include "extmod/modmachine.h"
 
-#if MICROPY_HW_USB_CDC_1200BPS_TOUCH && MICROPY_HW_ENABLE_USBDEV
-
+#if MICROPY_HW_USB_CDC
 #include "tusb.h"
+#include "shared/tinyusb/mp_usbd.h"
+
+static uint8_t cdc_itf_pending; // keep track of cdc interfaces which need attention to poll
+
+void tud_cdc_poll_interfaces(void) {
+    if (!cdc_itf_pending) {
+        // Explicitly run the USB stack as the scheduler may be locked (eg we are in
+        // an interrupt handler) while there is data pending.
+        mp_usbd_task();
+    }
+
+    // any CDC interfaces left to poll?
+    if (cdc_itf_pending && ringbuf_free(&stdin_ringbuf)) {
+        for (uint8_t itf = 0; itf < 8; ++itf) {
+            if (cdc_itf_pending & (1 << itf)) {
+                tud_cdc_rx_cb(itf);
+                if (!cdc_itf_pending) {
+                    break;
+                }
+            }
+        }
+    }
+}
+
+void tud_cdc_rx_cb(uint8_t itf) {
+    // consume pending USB data immediately to free usb buffer and keep the endpoint from stalling.
+    // in case the ringbuffer is full, mark the CDC interface that need attention later on for polling
+    cdc_itf_pending &= ~(1 << itf);
+    for (uint32_t bytes_avail = tud_cdc_n_available(itf); bytes_avail > 0; --bytes_avail) {
+        if (ringbuf_free(&stdin_ringbuf)) {
+            int data_char = tud_cdc_read_char();
+            #if MICROPY_KBD_EXCEPTION
+            if (data_char == mp_interrupt_char) {
+                // Clear the ring buffer
+                stdin_ringbuf.iget = stdin_ringbuf.iput = 0;
+                // and stop
+                mp_sched_keyboard_interrupt();
+            } else {
+                ringbuf_put(&stdin_ringbuf, data_char);
+            }
+            #else
+            ringbuf_put(&stdin_ringbuf, data_char);
+            #endif
+        } else {
+            cdc_itf_pending |= (1 << itf);
+            return;
+        }
+    }
+}
+
+mp_uint_t tud_cdc_tx_strn(const char *str, mp_uint_t len) {
+    size_t i = 0;
+    if (tud_cdc_connected()) {
+        while (i < len) {
+            uint32_t n = len - i;
+            if (n > CFG_TUD_CDC_EP_BUFSIZE) {
+                n = CFG_TUD_CDC_EP_BUFSIZE;
+            }
+            int timeout = 0;
+            // Wait with a max of USC_CDC_TIMEOUT ms
+            while (n > tud_cdc_write_available() && timeout++ < MICROPY_HW_USB_CDC_TX_TIMEOUT) {
+                mp_event_wait_ms(1);
+
+                // Explicitly run the USB stack as the scheduler may be locked (eg we
+                // are in an interrupt handler), while there is data pending.
+                mp_usbd_task();
+            }
+            if (timeout >= MICROPY_HW_USB_CDC_TX_TIMEOUT) {
+                break;
+            }
+            uint32_t n2 = tud_cdc_write(str + i, n);
+            tud_cdc_write_flush();
+            i += n2;
+        }
+    }
+    return i;
+}
+
+#if MICROPY_HW_USB_CDC_1200BPS_TOUCH && MICROPY_HW_ENABLE_USBDEV
 
 static mp_sched_node_t mp_bootloader_sched_node;
 
@@ -58,3 +136,4 @@ tud_cdc_line_state_cb
 }
 
 #endif
+#endif

shared/tinyusb/mp_cdc_common.h

@@ -0,0 +1,35 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2022 Blake W. Felt & Angus Gratton
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SHARED_TINYUSB_MP_CDC_COMMON_H
+#define MICROPY_INCLUDED_SHARED_TINYUSB_MP_CDC_COMMON_H
+
+void tud_cdc_poll_interfaces(void);
+void tud_cdc_rx_cb(uint8_t itf);
+bool tud_cdc_tx_strn(const char *str, mp_uint_t len);
+
+
+#endif // MICROPY_INCLUDED_SHARED_TINYUSB_MP_CDC_COMMON_H