mbed-os/features/nfc/stack/transceiver/pn512/pn512_cmd.c

149 lines
3.8 KiB
C

/*
* Copyright (c) 2013-2018, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* 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.
*/
/**
* \file pn512_cmd.c
* \copyright Copyright (c) ARM Ltd 2013
* \author Donatien Garnier
* \details Format and execute PN512 commands
* \internal
*/
#define __DEBUG__ 0
#ifndef __MODULE__
#define __MODULE__ "pn512_cmd.c"
#endif
#include "stack/nfc_errors.h"
#include "pn512_cmd.h"
#define PN512_FIFO_SIZE 64
#include "pn512.h"
#include "pn512_registers.h"
#include "pn512_irq.h"
#include "pn512_hw.h"
/** \addtogroup PN512
* \internal
* @{
* \name Commands
* @{
*/
/** \internal Initialize underlying pn512_cmd_t structure
* \param pPN512 pointer to pn512_t structure
*/
void pn512_cmd_init(pn512_t *pPN512)
{
(void) pPN512;
}
//Fifo read / write
/** \internal Write bytes to FIFO
* \param pPN512 pointer to pn512_t structure
* \param pData buffer to write
*/
void pn512_fifo_write(pn512_t *pPN512, ac_buffer_t *pData)
{
uint8_t fifo_space = pn512_fifo_space(pPN512); //Do not call this fn twice
size_t len = ac_buffer_reader_readable(pData);
len = MIN(fifo_space, len);
pn512_register_switch_page(pPN512, PN512_REG_FIFODATA);
pn512_hw_write_buffer(pPN512, PN512_REG_FIFODATA, pData, len);
}
/** \internal Read bytes from FIFO
* \param pPN512 pointer to pn512_t structure
* \param pData buffer in which to read
*/
void pn512_fifo_read(pn512_t *pPN512, ac_buffer_builder_t *pData)
{
uint8_t fifo_len = pn512_fifo_length(pPN512); //Do not call this fn twice
size_t len = ac_buffer_builder_writable(pData);
len = MIN(fifo_len, len);
pn512_register_switch_page(pPN512, PN512_REG_FIFODATA);
pn512_hw_read_buffer(pPN512, PN512_REG_FIFODATA, pData, len);
}
/** \internal Clear FIFO
* Removes any bytes left in FIFO
* \param pPN512 pointer to pn512_t structure
*/
void pn512_fifo_clear(pn512_t *pPN512)
{
pn512_register_write(pPN512, PN512_REG_FIFOLEVEL, 0x80); //Flush FIFO
}
/** \internal Get space in FIFO
* \param pPN512 pointer to pn512_t structure
* \return number of bytes that can be written to FIFO
*/
size_t pn512_fifo_space(pn512_t *pPN512)
{
return PN512_FIFO_SIZE - pn512_register_read(pPN512, PN512_REG_FIFOLEVEL);
}
/** \internal Get FIFO length
* \param pPN512 pointer to pn512_t structure
* \return number of bytes that can be read from FIFO
*/
size_t pn512_fifo_length(pn512_t *pPN512)
{
return pn512_register_read(pPN512, PN512_REG_FIFOLEVEL);
}
/** \internal Execute command
* \param pPN512 pointer to pn512_t structure
* \param cmd PN512 command to execute
*/
void pn512_cmd_exec(pn512_t *pPN512, uint8_t cmd)
{
pn512_register_write(pPN512, PN512_REG_COMMAND, cmd);
}
/** \internal Wait for command completion
* \param pPN512 pointer to pn512_t structure
* \param timeout timeout in milliseconds or -1 for blocking mode
* \return NFC_OK on success or NFC_ERR_TIMEOUT on timeout
*/
nfc_err_t pn512_cmd_wait_idle(pn512_t *pPN512, int timeout)
{
(void) timeout;
while (pn512_cmd_get(pPN512) != PN512_CMD_IDLE) {
}
return NFC_OK;
}
/** \internal Read executed command
* \param pPN512 pointer to pn512_t structure
* \return PN512 command being executed
*/
uint8_t pn512_cmd_get(pn512_t *pPN512)
{
return pn512_register_read(pPN512, PN512_REG_COMMAND) & PN512_CMD_REG_MASK;
}
/**
* @}
* @}
* */