/*

* 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 "lib/utils/interrupt_char.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) {

// 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) {

// 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;

}