mbed-os/usb/device/USBDevice/EndpointResolver.cpp

132 lines
3.4 KiB
C++

/* mbed Microcontroller Library
* Copyright (c) 2018-2018 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "mbed.h"
#include "EndpointResolver.h"
static uint32_t logical_to_index(uint32_t logical, bool in_not_out)
{
return (logical << 1) | (in_not_out ? 1 : 0);
}
static uint32_t index_to_logical(uint32_t index)
{
return index >> 1;
}
EndpointResolver::EndpointResolver(const usb_ep_table_t *table) : _table(table), _cost(0), _used(0), _valid(true)
{
// Do nothing
}
EndpointResolver::~EndpointResolver()
{
// Do nothing
}
void EndpointResolver::endpoint_ctrl(uint32_t size)
{
endpoint_in(USB_EP_TYPE_CTRL, size);
endpoint_out(USB_EP_TYPE_CTRL, size);
}
usb_ep_t EndpointResolver::next_free_endpoint(bool in_not_out, usb_ep_type_t type, uint32_t size)
{
int index = next_index(type, in_not_out);
if (index < 0) {
_valid = false;
return 0;
}
const usb_ep_entry_t &entry = _table->table[index_to_logical(index)];
_cost += entry.base_cost + entry.byte_cost * size;
_used |= 1 << index;
return index_to_endpoint(index);
}
usb_ep_t EndpointResolver::endpoint_in(usb_ep_type_t type, uint32_t size)
{
return next_free_endpoint(true, type, size);
}
usb_ep_t EndpointResolver::endpoint_out(usb_ep_type_t type, uint32_t size)
{
return next_free_endpoint(false, type, size);
}
bool EndpointResolver::valid()
{
return _valid && (_cost <= _table->resources);
}
void EndpointResolver::reset() {
_cost = 0;
_used = 0;
_valid = true;
}
usb_ep_t EndpointResolver::index_to_endpoint(int index)
{
return index_to_logical(index) | ((index & 1) ? 0x80 : 0);
}
int EndpointResolver::next_index(usb_ep_type_t type, bool in_not_out)
{
for (int logical = 0; logical < (int)(sizeof(_table->table) / sizeof(_table->table[0])); logical++) {
uint32_t index = logical_to_index(logical, in_not_out);
uint32_t other = logical_to_index(logical, !in_not_out);
const usb_ep_entry_t &entry = _table->table[logical];
usb_ep_attr_t dir = entry.attributes & USB_EP_ATTR_DIR_MASK;
bool in_allowed = dir != USB_EP_ATTR_DIR_OUT;
bool out_allowed = dir != USB_EP_ATTR_DIR_IN;
bool shared = dir == USB_EP_ATTR_DIR_IN_OR_OUT;
if (!(entry.attributes & (1 << type))) {
// This type is not supported
continue;
}
if (in_not_out && !in_allowed) {
// In endpoint not supported
continue;
}
if (!in_not_out && !out_allowed) {
// Out endpoint not supported
continue;
}
if (_used & (1 << index)) {
// This endpoint is in use
continue;
}
if (shared && (_used & (1 << other))) {
// This endpoint can only be one direction at a time and is in
// use by the other direction
continue;
}
return index;
}
// Not found
return -1;
}