libnfc/libnfc/drivers/pn532_uart.c

347 lines
10 KiB
C

/*-
* Public platform independent Near Field Communication (NFC) library
*
* Copyright (C) 2009, Roel Verdult
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>
*/
/**
* @file pn532_uart.c
* @brief PN532 driver using UART bus (UART, RS232, etc.)
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif // HAVE_CONFIG_H
#include "../drivers.h"
#include <stdio.h>
#include <string.h>
#include "pn532_uart.h"
#include <nfc/nfc.h>
#include <nfc/nfc-messages.h>
// Bus
#include "uart.h"
#define BUFFER_LENGTH 256
#define SERIAL_DEFAULT_PORT_SPEED 115200
// TODO Move this one level up for libnfc-1.6
static const byte_t ack_frame[] = { 0x00, 0x00, 0xff, 0x00, 0xff, 0x00 };
void pn532_uart_ack (const nfc_device_spec_t nds);
void pn532_uart_wakeup (const nfc_device_spec_t nds);
bool pn532_uart_check_communication (const nfc_device_spec_t nds, bool * success);
nfc_device_desc_t *
pn532_uart_pick_device (void)
{
nfc_device_desc_t *pndd;
if ((pndd = malloc (sizeof (*pndd)))) {
size_t szN;
if (!pn532_uart_list_devices (pndd, 1, &szN)) {
DBG ("%s", "pn532_uart_list_devices failed");
return NULL;
}
if (szN == 0) {
DBG ("%s", "No device found");
return NULL;
}
}
return pndd;
}
bool
pn532_uart_list_devices (nfc_device_desc_t pnddDevices[], size_t szDevices, size_t * pszDeviceFound)
{
/** @note: Due to UART bus we can't know if its really a pn532 without
* sending some PN53x commands. But using this way to probe devices, we can
* have serious problem with other device on this bus */
#ifndef SERIAL_AUTOPROBE_ENABLED
(void) pnddDevices;
(void) szDevices;
*pszDeviceFound = 0;
DBG ("%s", "Serial auto-probing have been disabled at compile time. Skipping autoprobe.");
return false;
#else /* SERIAL_AUTOPROBE_ENABLED */
*pszDeviceFound = 0;
serial_port sp;
const char *pcPorts[] = DEFAULT_SERIAL_PORTS;
const char *pcPort;
int iDevice = 0;
while ((pcPort = pcPorts[iDevice++])) {
sp = uart_open (pcPort);
DBG ("Trying to find PN532 device on serial port: %s at %d bauds.", pcPort, SERIAL_DEFAULT_PORT_SPEED);
if ((sp != INVALID_SERIAL_PORT) && (sp != CLAIMED_SERIAL_PORT)) {
bool bComOk;
// Serial port claimed but we need to check if a PN532_UART is connected.
uart_set_speed (sp, SERIAL_DEFAULT_PORT_SPEED);
// Send ACK frame to cancel a previous command
pn532_uart_ack ((nfc_device_spec_t) sp);
// PN532 could be powered down, we need to wake it up before line testing.
pn532_uart_wakeup ((nfc_device_spec_t) sp);
// Check communication using "Diagnose" command, with "Comunication test" (0x00)
if (!pn532_uart_check_communication ((nfc_device_spec_t) sp, &bComOk))
return false;
if (!bComOk)
continue;
uart_close (sp);
snprintf (pnddDevices[*pszDeviceFound].acDevice, DEVICE_NAME_LENGTH - 1, "%s (%s)", "PN532", pcPort);
pnddDevices[*pszDeviceFound].acDevice[DEVICE_NAME_LENGTH - 1] = '\0';
pnddDevices[*pszDeviceFound].pcDriver = PN532_UART_DRIVER_NAME;
pnddDevices[*pszDeviceFound].pcPort = strdup (pcPort);
pnddDevices[*pszDeviceFound].uiSpeed = SERIAL_DEFAULT_PORT_SPEED;
DBG ("Device found: %s.", pnddDevices[*pszDeviceFound].acDevice);
(*pszDeviceFound)++;
// Test if we reach the maximum "wanted" devices
if ((*pszDeviceFound) >= szDevices)
break;
}
# ifdef DEBUG
if (sp == INVALID_SERIAL_PORT)
DBG ("Invalid serial port: %s", pcPort);
if (sp == CLAIMED_SERIAL_PORT)
DBG ("Serial port already claimed: %s", pcPort);
# endif
/* DEBUG */
}
#endif /* SERIAL_AUTOPROBE_ENABLED */
return true;
}
nfc_device_t *
pn532_uart_connect (const nfc_device_desc_t * pndd)
{
serial_port sp;
nfc_device_t *pnd = NULL;
bool bComOk;
DBG ("Attempt to connect to: %s at %d bauds.", pndd->pcPort, pndd->uiSpeed);
sp = uart_open (pndd->pcPort);
if (sp == INVALID_SERIAL_PORT)
ERR ("Invalid serial port: %s", pndd->pcPort);
if (sp == CLAIMED_SERIAL_PORT)
ERR ("Serial port already claimed: %s", pndd->pcPort);
if ((sp == CLAIMED_SERIAL_PORT) || (sp == INVALID_SERIAL_PORT))
return NULL;
uart_set_speed (sp, pndd->uiSpeed);
// PN532 could be powered down, we need to wake it up before line testing.
pn532_uart_wakeup ((nfc_device_spec_t) sp);
// Check communication using "Diagnose" command, with "Comunication test" (0x00)
if (!pn532_uart_check_communication ((nfc_device_spec_t) sp, &bComOk))
return NULL;
if (!bComOk)
return NULL;
DBG ("Successfully connected to: %s", pndd->pcPort);
// We have a connection
pnd = malloc (sizeof (nfc_device_t));
strncpy (pnd->acName, pndd->acDevice, DEVICE_NAME_LENGTH - 1);
pnd->acName[DEVICE_NAME_LENGTH - 1] = '\0';
pnd->nc = NC_PN532;
pnd->nds = (nfc_device_spec_t) sp;
pnd->bActive = true;
return pnd;
}
void
pn532_uart_disconnect (nfc_device_t * pnd)
{
uart_close ((serial_port) pnd->nds);
free (pnd);
}
bool
pn532_uart_transceive (nfc_device_t * pnd, const byte_t * pbtTx, const size_t szTxLen, byte_t * pbtRx,
size_t * pszRxLen)
{
byte_t abtTxBuf[BUFFER_LENGTH] = { 0x00, 0x00, 0xff }; // Every packet must start with "00 00 ff"
byte_t abtRxBuf[BUFFER_LENGTH];
size_t szRxBufLen = BUFFER_LENGTH;
size_t szPos;
int res;
// Packet length = data length (len) + checksum (1) + end of stream marker (1)
abtTxBuf[3] = szTxLen;
// Packet length checksum
abtTxBuf[4] = BUFFER_LENGTH - abtTxBuf[3];
// Copy the PN53X command into the packet buffer
memmove (abtTxBuf + 5, pbtTx, szTxLen);
// Calculate data payload checksum
abtTxBuf[szTxLen + 5] = 0;
for (szPos = 0; szPos < szTxLen; szPos++) {
abtTxBuf[szTxLen + 5] -= abtTxBuf[szPos + 5];
}
// End of stream marker
abtTxBuf[szTxLen + 6] = 0;
#ifdef DEBUG
PRINT_HEX ("TX", abtTxBuf, szTxLen + 7);
#endif
res = uart_send ((serial_port) pnd->nds, abtTxBuf, szTxLen + 7);
if (res != 0) {
ERR ("%s", "Unable to transmit data. (TX)");
pnd->iLastError = res;
return false;
}
res = uart_receive ((serial_port) pnd->nds, abtRxBuf, &szRxBufLen);
if (res != 0) {
ERR ("%s", "Unable to receive data. (RX)");
pnd->iLastError = res;
return false;
}
#ifdef DEBUG
PRINT_HEX ("RX", abtRxBuf, szRxBufLen);
#endif
// WARN: UART is a per byte reception, so you usually receive ACK and next frame the same time
if (!pn53x_transceive_check_ack_frame_callback (pnd, abtRxBuf, szRxBufLen))
return false;
szRxBufLen -= sizeof (ack_frame);
memmove (abtRxBuf, abtRxBuf + sizeof (ack_frame), szRxBufLen);
if (szRxBufLen == 0) {
szRxBufLen = BUFFER_LENGTH;
do {
delay_ms (10);
res = uart_receive ((serial_port) pnd->nds, abtRxBuf, &szRxBufLen);
} while (res != 0);
#ifdef DEBUG
PRINT_HEX ("RX", abtRxBuf, szRxBufLen);
#endif
}
#ifdef DEBUG
PRINT_HEX ("TX", ack_frame, 6);
#endif
res = uart_send ((serial_port) pnd->nds, ack_frame, 6);
if (res != 0) {
ERR ("%s", "Unable to transmit data. (TX)");
pnd->iLastError = res;
return false;
}
if (!pn53x_transceive_check_error_frame_callback (pnd, abtRxBuf, szRxBufLen))
return false;
// When the answer should be ignored, just return a successful result
if (pbtRx == NULL || pszRxLen == NULL)
return true;
// Only succeed when the result is at least 00 00 FF xx Fx Dx xx .. .. .. xx 00 (x = variable)
if (szRxBufLen < 9) {
pnd->iLastError = DEINVAL;
return false;
}
// Remove the preceding and appending bytes 00 00 ff 00 ff 00 00 00 FF xx Fx .. .. .. xx 00 (x = variable)
*pszRxLen = szRxBufLen - 9;
memcpy (pbtRx, abtRxBuf + 7, *pszRxLen);
return true;
}
void
pn532_uart_ack (const nfc_device_spec_t nds)
{
#ifdef DEBUG
PRINT_HEX ("TX", ack_frame, sizeof (ack_frame));
#endif
uart_send ((serial_port) nds, ack_frame, sizeof (ack_frame));
}
void
pn532_uart_wakeup (const nfc_device_spec_t nds)
{
byte_t abtRx[BUFFER_LENGTH];
size_t szRxLen;
/** PN532C106 wakeup. */
/** High Speed Unit (HSU) wake up consist to send 0x55 and wait a "long" delay for PN532 being wakeup. */
/** After the preamble we request the PN532C106 chip to switch to "normal" mode (SAM is not used) */
const byte_t pncmd_pn532c106_wakeup_preamble[] =
{ 0x55, 0x55, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x03, 0xfd, 0xd4, 0x14, 0x01, 0x17, 0x00, 0x00, 0xff, 0x03, 0xfd,
0xd4, 0x14, 0x01, 0x17, 0x00 };
#ifdef DEBUG
PRINT_HEX ("TX", pncmd_pn532c106_wakeup_preamble, sizeof (pncmd_pn532c106_wakeup_preamble));
#endif
uart_send ((serial_port) nds, pncmd_pn532c106_wakeup_preamble, sizeof (pncmd_pn532c106_wakeup_preamble));
if (0 == uart_receive ((serial_port) nds, abtRx, &szRxLen)) {
#ifdef DEBUG
PRINT_HEX ("RX", abtRx, szRxLen);
#endif
}
}
bool
pn532_uart_check_communication (const nfc_device_spec_t nds, bool * success)
{
byte_t abtRx[BUFFER_LENGTH];
size_t szRxLen;
const byte_t attempted_result[] =
{ 0x00, 0x00, 0xff, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff, 0x09, 0xf7, 0xD5, 0x01, 0x00, 'l', 'i', 'b', 'n', 'f', 'c',
0xbc, 0x00 };
int res;
/** To be sure that PN532 is alive, we have put a "Diagnose" command to execute a "Communication Line Test" */
const byte_t pncmd_communication_test[] =
{ 0x00, 0x00, 0xff, 0x09, 0xf7, 0xd4, 0x00, 0x00, 'l', 'i', 'b', 'n', 'f', 'c', 0xbe, 0x00 };
*success = false;
#ifdef DEBUG
PRINT_HEX ("TX", pncmd_communication_test, sizeof (pncmd_communication_test));
#endif
res = uart_send ((serial_port) nds, pncmd_communication_test, sizeof (pncmd_communication_test));
if (res != 0) {
ERR ("%s", "Unable to transmit data. (TX)");
return false;
}
res = uart_receive ((serial_port) nds, abtRx, &szRxLen);
if (res != 0) {
ERR ("%s", "Unable to receive data. (RX)");
return false;
}
#ifdef DEBUG
PRINT_HEX ("RX", abtRx, szRxLen);
#endif
if (0 == memcmp (abtRx, attempted_result, sizeof (attempted_result)))
*success = true;
return true;
}