/*
* Copyright (C) 2010 NXP Semiconductors
*
* 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 phDalNfc_uart.c
* \brief DAL com port implementation for linux
*
* Project: Trusted NFC Linux Lignt
*
* $Date: 07 aug 2009
* $Author: Jonathan roux
* $Revision: 1.0 $
*
*/
#define LOG_TAG "NFC_uart"
#include <cutils/log.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <sys/select.h>
#include <stdio.h>
#include <errno.h>
#include <phDal4Nfc_debug.h>
#include <phDal4Nfc_uart.h>
#include <phOsalNfc.h>
#include <phNfcStatus.h>
#if defined(ANDROID)
#include <string.h>
#include <cutils/properties.h> // for property_get
#endif
typedef struct
{
int nHandle;
char nOpened;
struct termios nIoConfigBackup;
struct termios nIoConfig;
} phDal4Nfc_ComPortContext_t;
/*-----------------------------------------------------------------------------------
COM PORT CONFIGURATION
------------------------------------------------------------------------------------*/
#define DAL_BAUD_RATE B115200
/*-----------------------------------------------------------------------------------
VARIABLES
------------------------------------------------------------------------------------*/
static phDal4Nfc_ComPortContext_t gComPortContext;
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_set_open_from_handle
PURPOSE: Initialize internal variables
-----------------------------------------------------------------------------*/
void phDal4Nfc_uart_initialize(void)
{
memset(&gComPortContext, 0, sizeof(phDal4Nfc_ComPortContext_t));
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_set_open_from_handle
PURPOSE: The application could have opened the link itself. So we just need
to get the handle and consider that the open operation has already
been done.
-----------------------------------------------------------------------------*/
void phDal4Nfc_uart_set_open_from_handle(phHal_sHwReference_t * pDalHwContext)
{
gComPortContext.nHandle = (int) pDalHwContext->p_board_driver;
DAL_ASSERT_STR(gComPortContext.nHandle >= 0, "Bad passed com port handle");
gComPortContext.nOpened = 1;
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_is_opened
PURPOSE: Returns if the link is opened or not. (0 = not opened; 1 = opened)
-----------------------------------------------------------------------------*/
int phDal4Nfc_uart_is_opened(void)
{
return gComPortContext.nOpened;
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_flush
PURPOSE: Flushes the link ; clears the link buffers
-----------------------------------------------------------------------------*/
void phDal4Nfc_uart_flush(void)
{
int ret;
/* flushes the com port */
ret = tcflush(gComPortContext.nHandle, TCIFLUSH);
DAL_ASSERT_STR(ret!=-1, "tcflush failed");
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_close
PURPOSE: Closes the link
-----------------------------------------------------------------------------*/
void phDal4Nfc_uart_close(void)
{
if (gComPortContext.nOpened == 1)
{
close(gComPortContext.nHandle);
gComPortContext.nHandle = 0;
gComPortContext.nOpened = 0;
}
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_close
PURPOSE: Closes the link
-----------------------------------------------------------------------------*/
NFCSTATUS phDal4Nfc_uart_open_and_configure(pphDal4Nfc_sConfig_t pConfig, void ** pLinkHandle)
{
char * pComPort;
int nComStatus;
NFCSTATUS nfcret = NFCSTATUS_SUCCESS;
int ret;
DAL_ASSERT_STR(gComPortContext.nOpened==0, "Trying to open but already done!");
srand(time(NULL));
switch(pConfig->nLinkType)
{
case ENUM_DAL_LINK_TYPE_COM1:
pComPort = "/dev/ttyO0";
break;
case ENUM_DAL_LINK_TYPE_COM2:
pComPort = "/dev/ttyO1";
break;
case ENUM_DAL_LINK_TYPE_COM3:
pComPort = "/dev/ttyO2";
break;
case ENUM_DAL_LINK_TYPE_COM4:
pComPort = "/dev/ttyO3";
break;
case ENUM_DAL_LINK_TYPE_COM5:
pComPort = "/dev/ttyO4";
break;
case ENUM_DAL_LINK_TYPE_COM6:
pComPort = "/dev/ttyO5";
break;
case ENUM_DAL_LINK_TYPE_COM7:
pComPort = "/dev/ttyO6";
break;
case ENUM_DAL_LINK_TYPE_COM8:
pComPort = "/dev/ttyO7";
break;
case ENUM_DAL_LINK_TYPE_USB:
pComPort = "/dev/ttyUSB0";
break;
default:
return NFCSTATUS_INVALID_PARAMETER;
}
/* open communication port handle */
gComPortContext.nHandle = open(pComPort, O_RDWR | O_NOCTTY);
if (gComPortContext.nHandle < 0)
{
*pLinkHandle = NULL;
return PHNFCSTVAL(CID_NFC_DAL, NFCSTATUS_INVALID_DEVICE);
}
gComPortContext.nOpened = 1;
*pLinkHandle = (void*)gComPortContext.nHandle;
/*
* Now configure the com port
*/
ret = tcgetattr(gComPortContext.nHandle, &gComPortContext.nIoConfigBackup); /* save the old io config */
if (ret == -1)
{
/* tcgetattr failed -- it is likely that the provided port is invalid */
*pLinkHandle = NULL;
return PHNFCSTVAL(CID_NFC_DAL, NFCSTATUS_INVALID_DEVICE);
}
ret = fcntl(gComPortContext.nHandle, F_SETFL, 0); /* Makes the read blocking (default). */
DAL_ASSERT_STR(ret != -1, "fcntl failed");
/* Configures the io */
memset((void *)&gComPortContext.nIoConfig, (int)0, (size_t)sizeof(struct termios));
/*
BAUDRATE: Set bps rate. You could also use cfsetispeed and cfsetospeed.
CRTSCTS : output hardware flow control (only used if the cable has
all necessary lines. See sect. 7 of Serial-HOWTO)
CS8 : 8n1 (8bit,no parity,1 stopbit)
CLOCAL : local connection, no modem contol
CREAD : enable receiving characters
*/
gComPortContext.nIoConfig.c_cflag = DAL_BAUD_RATE | CS8 | CLOCAL | CREAD; /* Control mode flags */
gComPortContext.nIoConfig.c_iflag = IGNPAR; /* Input mode flags : IGNPAR Ignore parity errors */
gComPortContext.nIoConfig.c_oflag = 0; /* Output mode flags */
gComPortContext.nIoConfig.c_lflag = 0; /* Local mode flags. Read mode : non canonical, no echo */
gComPortContext.nIoConfig.c_cc[VTIME] = 0; /* Control characters. No inter-character timer */
gComPortContext.nIoConfig.c_cc[VMIN] = 1; /* Control characters. Read is blocking until X characters are read */
/*
TCSANOW Make changes now without waiting for data to complete
TCSADRAIN Wait until everything has been transmitted
TCSAFLUSH Flush input and output buffers and make the change
*/
ret = tcsetattr(gComPortContext.nHandle, TCSANOW, &gComPortContext.nIoConfig);
DAL_ASSERT_STR(ret != -1, "tcsetattr failed");
/*
On linux the DTR signal is set by default. That causes a problem for pn544 chip
because this signal is connected to "reset". So we clear it. (on windows it is cleared by default).
*/
ret = ioctl(gComPortContext.nHandle, TIOCMGET, &nComStatus);
DAL_ASSERT_STR(ret != -1, "ioctl TIOCMGET failed");
nComStatus &= ~TIOCM_DTR;
ret = ioctl(gComPortContext.nHandle, TIOCMSET, &nComStatus);
DAL_ASSERT_STR(ret != -1, "ioctl TIOCMSET failed");
DAL_DEBUG("Com port status=%d\n", nComStatus);
usleep(10000); /* Mandatory sleep so that the DTR line is ready before continuing */
return nfcret;
}
/*
adb shell setprop debug.nfc.UART_ERROR_RATE X
will corrupt and drop bytes in uart_read(), to test the error handling
of DAL & LLC errors.
*/
int property_error_rate = 0;
static void read_property() {
char value[PROPERTY_VALUE_MAX];
property_get("debug.nfc.UART_ERROR_RATE", value, "0");
property_error_rate = atoi(value);
}
/* returns length of buffer after errors */
static int apply_errors(uint8_t *buffer, int length) {
int i;
if (!property_error_rate) return length;
for (i = 0; i < length; i++) {
if (rand() % 1000 < property_error_rate) {
if (rand() % 2) {
// 50% chance of dropping byte
length--;
memcpy(&buffer[i], &buffer[i+1], length-i);
LOGW("dropped byte %d", i);
} else {
// 50% chance of corruption
buffer[i] = (uint8_t)rand();
LOGW("corrupted byte %d", i);
}
}
}
return length;
}
static struct timeval timeval_remaining(struct timespec timeout) {
struct timespec now;
struct timeval delta;
clock_gettime(CLOCK_MONOTONIC, &now);
delta.tv_sec = timeout.tv_sec - now.tv_sec;
delta.tv_usec = (timeout.tv_nsec - now.tv_nsec) / (long)1000;
if (delta.tv_usec < 0) {
delta.tv_usec += 1000000;
delta.tv_sec--;
}
if (delta.tv_sec < 0) {
delta.tv_sec = 0;
delta.tv_usec = 0;
}
return delta;
}
static int libnfc_firmware_mode = 0;
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_read
PURPOSE: Reads nNbBytesToRead bytes and writes them in pBuffer.
Returns the number of bytes really read or -1 in case of error.
-----------------------------------------------------------------------------*/
int phDal4Nfc_uart_read(uint8_t * pBuffer, int nNbBytesToRead)
{
int ret;
int numRead = 0;
struct timeval tv;
struct timeval *ptv;
struct timespec timeout;
fd_set rfds;
DAL_ASSERT_STR(gComPortContext.nOpened == 1, "read called but not opened!");
DAL_DEBUG("_uart_read() called to read %d bytes", nNbBytesToRead);
read_property();
// Read timeout:
// FW mode: 10s timeout
// 1 byte read: steady-state LLC length read, allowed to block forever
// >1 byte read: LLC payload, 100ms timeout (before pn544 re-transmit)
if (nNbBytesToRead > 1 && !libnfc_firmware_mode) {
clock_gettime(CLOCK_MONOTONIC, &timeout);
timeout.tv_nsec += 100000000;
if (timeout.tv_nsec > 1000000000) {
timeout.tv_sec++;
timeout.tv_nsec -= 1000000000;
}
ptv = &tv;
} else if (libnfc_firmware_mode) {
clock_gettime(CLOCK_MONOTONIC, &timeout);
timeout.tv_sec += 10;
ptv = &tv;
} else {
ptv = NULL;
}
while (numRead < nNbBytesToRead) {
FD_ZERO(&rfds);
FD_SET(gComPortContext.nHandle, &rfds);
if (ptv) {
tv = timeval_remaining(timeout);
ptv = &tv;
}
ret = select(gComPortContext.nHandle + 1, &rfds, NULL, NULL, ptv);
if (ret < 0) {
DAL_DEBUG("select() errno=%d", errno);
if (errno == EINTR || errno == EAGAIN) {
continue;
}
return -1;
} else if (ret == 0) {
LOGW("timeout!");
break; // return partial response
}
ret = read(gComPortContext.nHandle, pBuffer + numRead, nNbBytesToRead - numRead);
if (ret > 0) {
ret = apply_errors(pBuffer + numRead, ret);
DAL_DEBUG("read %d bytes", ret);
numRead += ret;
} else if (ret == 0) {
DAL_PRINT("_uart_read() EOF");
return 0;
} else {
DAL_DEBUG("_uart_read() errno=%d", errno);
if (errno == EINTR || errno == EAGAIN) {
continue;
}
return -1;
}
}
return numRead;
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_link_write
PURPOSE: Writes nNbBytesToWrite bytes from pBuffer to the link
Returns the number of bytes that have been wrote to the interface or -1 in case of error.
-----------------------------------------------------------------------------*/
int phDal4Nfc_uart_write(uint8_t * pBuffer, int nNbBytesToWrite)
{
int ret;
int numWrote = 0;
DAL_ASSERT_STR(gComPortContext.nOpened == 1, "write called but not opened!");
DAL_DEBUG("_uart_write() called to write %d bytes\n", nNbBytesToWrite);
while (numWrote < nNbBytesToWrite) {
ret = write(gComPortContext.nHandle, pBuffer + numWrote, nNbBytesToWrite - numWrote);
if (ret > 0) {
DAL_DEBUG("wrote %d bytes", ret);
numWrote += ret;
} else if (ret == 0) {
DAL_PRINT("_uart_write() EOF");
return -1;
} else {
DAL_DEBUG("_uart_write() errno=%d", errno);
if (errno == EINTR || errno == EAGAIN) {
continue;
}
return -1;
}
}
return numWrote;
}
/*-----------------------------------------------------------------------------
FUNCTION: phDal4Nfc_uart_reset
PURPOSE: Reset the PN544, using the VEN pin
-----------------------------------------------------------------------------*/
int phDal4Nfc_uart_reset(long level)
{
static const char NFC_POWER_PATH[] = "/sys/devices/platform/nfc-power/nfc_power";
int sz;
int fd = -1;
int ret = NFCSTATUS_FAILED;
char buffer[2];
DAL_DEBUG("phDal4Nfc_uart_reset, VEN level = %ld", level);
if (snprintf(buffer, sizeof(buffer), "%u", (unsigned int)level) != 1) {
LOGE("Bad nfc power level (%u)", (unsigned int)level);
goto out;
}
fd = open(NFC_POWER_PATH, O_WRONLY);
if (fd < 0) {
LOGE("open(%s) for write failed: %s (%d)", NFC_POWER_PATH,
strerror(errno), errno);
goto out;
}
sz = write(fd, &buffer, sizeof(buffer) - 1);
if (sz < 0) {
LOGE("write(%s) failed: %s (%d)", NFC_POWER_PATH, strerror(errno),
errno);
goto out;
}
ret = NFCSTATUS_SUCCESS;
if (level == 2) {
libnfc_firmware_mode = 1;
} else {
libnfc_firmware_mode = 0;
}
out:
if (fd >= 0) {
close(fd);
}
return ret;
}