esp-idf/components/usb/usb_private.c

39 wiersze
1.3 KiB
C

/*
* SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "esp_heap_caps.h"
#include "usb_private.h"
#include "usb/usb_types_ch9.h"
urb_t *urb_alloc(size_t data_buffer_size, size_t header_size, int num_isoc_packets)
{
urb_t *urb = heap_caps_calloc(1, sizeof(urb_t) + (sizeof(usb_isoc_packet_desc_t) * num_isoc_packets), MALLOC_CAP_DEFAULT);
uint8_t *data_buffer = heap_caps_malloc(data_buffer_size + header_size, MALLOC_CAP_DMA);
if (urb == NULL || data_buffer == NULL) {
goto err;
}
urb->usb_host_header_size = header_size; //Indicate that this URB's data_buffer has a header in front of it.
//Case as dummy transfer to write to initialize const fields
usb_transfer_dummy_t *dummy_transfer = (usb_transfer_dummy_t *)&urb->transfer;
dummy_transfer->data_buffer = (uint8_t *)(data_buffer + header_size);
dummy_transfer->data_buffer_size = data_buffer_size;
dummy_transfer->num_isoc_packets = num_isoc_packets;
return urb;
err:
heap_caps_free(urb);
heap_caps_free(data_buffer);
return NULL;
}
void urb_free(urb_t *urb)
{
if (urb == NULL) {
return;
}
heap_caps_free((uint8_t *)(urb->transfer.data_buffer - urb->usb_host_header_size));
heap_caps_free(urb);
}