add circuitpython code

1 files changed, 158 insertions, 0 deletions

diff --git a/circuitpython/shared-module/usb_cdc/Serial.c b/circuitpython/shared-module/usb_cdc/Serial.c
new file mode 100644
index 0000000..7f1bc75
--- /dev/null
+++ b/circuitpython/shared-module/usb_cdc/Serial.c
@@ -0,0 +1,158 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Dan Halbert for Adafruit Industries
+ *
+ * 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 "shared/runtime/interrupt_char.h"
+#include "shared-bindings/usb_cdc/Serial.h"
+#include "shared-module/usb_cdc/Serial.h"
+#include "supervisor/shared/tick.h"
+
+#include "tusb.h"
+
+size_t common_hal_usb_cdc_serial_read(usb_cdc_serial_obj_t *self, uint8_t *data, size_t len, int *errcode) {
+
+    const bool wait_forever = self->timeout < 0.0f;
+    const bool wait_for_timeout = self->timeout > 0.0f;
+
+    // Read up to len bytes immediately.
+    // The number of bytes read will not be larger than what is already in the TinyUSB FIFO.
+    uint32_t total_num_read = tud_cdc_n_read(self->idx, data, len);
+
+    if (wait_forever || wait_for_timeout) {
+        // Continue filling the buffer past what we already read.
+        len -= total_num_read;
+        data += total_num_read;
+
+        // Read more if we have time.
+        // Use special routine to avoid pulling in uint64-float-compatible math routines.
+        uint64_t timeout_ms = float_to_uint64(self->timeout * 1000);  // Junk value if timeout < 0.
+        uint64_t start_ticks = supervisor_ticks_ms64();
+
+        uint32_t num_read = 0;
+        while (total_num_read < len &&
+               (wait_forever || supervisor_ticks_ms64() - start_ticks <= timeout_ms)) {
+
+            // Wait for a bit, and check for ctrl-C.
+            RUN_BACKGROUND_TASKS;
+            if (mp_hal_is_interrupted()) {
+                return 0;
+            }
+
+            // Advance buffer pointer and reduce number of bytes that need to be read.
+            len -= num_read;
+            data += num_read;
+
+            // Try to read another batch of bytes.
+            num_read = tud_cdc_n_read(self->idx, data, len);
+            total_num_read += num_read;
+        }
+    }
+
+    return total_num_read;
+}
+
+size_t common_hal_usb_cdc_serial_write(usb_cdc_serial_obj_t *self, const uint8_t *data, size_t len, int *errcode) {
+    const bool wait_forever = self->write_timeout < 0.0f;
+    const bool wait_for_timeout = self->write_timeout > 0.0f;
+
+    // Write as many bytes as possible immediately.
+    // The number of bytes written at once will not be larger than what can fit in the TinyUSB FIFO.
+    uint32_t total_num_written = tud_cdc_n_write(self->idx, data, len);
+    tud_cdc_n_write_flush(self->idx);
+
+    if (wait_forever || wait_for_timeout) {
+        // Continue writing the rest of the buffer.
+        len -= total_num_written;
+        data += total_num_written;
+
+        // Write more if we have time.
+        // Use special routine to avoid pulling in uint64-float-compatible math routines.
+        uint64_t timeout_ms = float_to_uint64(self->write_timeout * 1000);  // Junk value if write_timeout < 0.
+        uint64_t start_ticks = supervisor_ticks_ms64();
+
+        uint32_t num_written = 0;
+        while (total_num_written < len &&
+               (wait_forever || supervisor_ticks_ms64() - start_ticks <= timeout_ms)) {
+
+            // Wait for a bit, and check for ctrl-C.
+            RUN_BACKGROUND_TASKS;
+            if (mp_hal_is_interrupted()) {
+                return 0;
+            }
+
+            // Advance buffer pointer and reduce number of bytes that need to be written.
+            len -= num_written;
+            data += num_written;
+
+            // Try to write another batch of bytes.
+            num_written = tud_cdc_n_write(self->idx, data, len);
+            tud_cdc_n_write_flush(self->idx);
+            total_num_written += num_written;
+        }
+    }
+
+    return total_num_written;
+}
+
+uint32_t common_hal_usb_cdc_serial_get_in_waiting(usb_cdc_serial_obj_t *self) {
+    return tud_cdc_n_available(self->idx);
+}
+
+uint32_t common_hal_usb_cdc_serial_get_out_waiting(usb_cdc_serial_obj_t *self) {
+    // Return number of FIFO bytes currently occupied.
+    return CFG_TUD_CDC_TX_BUFSIZE - tud_cdc_n_write_available(self->idx);
+}
+
+void common_hal_usb_cdc_serial_reset_input_buffer(usb_cdc_serial_obj_t *self) {
+    tud_cdc_n_read_flush(self->idx);
+}
+
+uint32_t common_hal_usb_cdc_serial_reset_output_buffer(usb_cdc_serial_obj_t *self) {
+    return tud_cdc_n_write_clear(self->idx);
+}
+
+uint32_t common_hal_usb_cdc_serial_flush(usb_cdc_serial_obj_t *self) {
+    return tud_cdc_n_write_flush(self->idx);
+}
+
+bool common_hal_usb_cdc_serial_get_connected(usb_cdc_serial_obj_t *self) {
+    return tud_cdc_n_connected(self->idx);
+}
+
+mp_float_t common_hal_usb_cdc_serial_get_timeout(usb_cdc_serial_obj_t *self) {
+    return self->timeout;
+}
+
+void common_hal_usb_cdc_serial_set_timeout(usb_cdc_serial_obj_t *self, mp_float_t timeout) {
+    self->timeout = timeout;
+}
+
+mp_float_t common_hal_usb_cdc_serial_get_write_timeout(usb_cdc_serial_obj_t *self) {
+    return self->write_timeout;
+}
+
+void common_hal_usb_cdc_serial_set_write_timeout(usb_cdc_serial_obj_t *self, mp_float_t write_timeout) {
+    self->write_timeout = write_timeout;
+}