esp32: Add support for USB with CDC ACM.

The REPL will be available on the USB serial port. Signed-off-by: Damien George <damien@micropython.org>
2021-02-19 12:08:11 +11:00
parent 66a86a0615
commit c81d048bb3
6 changed files with 145 additions and 1 deletions
--- a/ports/esp32/usb.c
+++ b/ports/esp32/usb.c
@@ -0,0 +1,92 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Damien P. George
+ *
+ * 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.
+ */
+
+#include "py/runtime.h"
+#include "py/mphal.h"
+#include "usb.h"
+
+#if CONFIG_USB_ENABLED
+
+#include "tinyusb.h"
+#include "tusb_cdc_acm.h"
+
+#define CDC_ITF TINYUSB_CDC_ACM_0
+
+static uint8_t usb_rx_buf[CONFIG_USB_CDC_RX_BUFSIZE];
+
+static void usb_callback_rx(int itf, cdcacm_event_t *event) {
+    // TODO: what happens if more chars come in during this function, are they lost?
+    for (;;) {
+        size_t len = 0;
+        esp_err_t ret = tinyusb_cdcacm_read(itf, usb_rx_buf, sizeof(usb_rx_buf), &len);
+        if (ret != ESP_OK) {
+            break;
+        }
+        if (len == 0) {
+            break;
+        }
+        for (size_t i = 0; i < len; ++i) {
+            if (usb_rx_buf[i] == mp_interrupt_char) {
+                mp_keyboard_interrupt();
+            } else {
+                ringbuf_put(&stdin_ringbuf, usb_rx_buf[i]);
+            }
+        }
+    }
+}
+
+void usb_init(void) {
+    // Initialise the USB with defaults.
+    tinyusb_config_t tusb_cfg = {0};
+    ESP_ERROR_CHECK(tinyusb_driver_install(&tusb_cfg));
+
+    // Initialise the USB serial interface.
+    tinyusb_config_cdcacm_t amc_cfg = {
+        .usb_dev = TINYUSB_USBDEV_0,
+        .cdc_port = CDC_ITF,
+        .rx_unread_buf_sz = 256,
+        .callback_rx = &usb_callback_rx,
+        .callback_rx_wanted_char = NULL,
+        .callback_line_state_changed = NULL,
+        .callback_line_coding_changed = NULL
+    };
+    ESP_ERROR_CHECK(tusb_cdc_acm_init(&amc_cfg));
+}
+
+void usb_tx_strn(const char *str, size_t len) {
+    while (len) {
+        size_t l = len;
+        if (l > CONFIG_USB_CDC_TX_BUFSIZE) {
+            l = CONFIG_USB_CDC_TX_BUFSIZE;
+        }
+        tinyusb_cdcacm_write_queue(CDC_ITF, (uint8_t *)str, l);
+        tinyusb_cdcacm_write_flush(CDC_ITF, pdMS_TO_TICKS(1000));
+        str += l;
+        len -= l;
+    }
+}
+
+#endif // CONFIG_USB_ENABLED