i2cread.c File Reference

Read an I2C device. More...

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <libgen.h>
#include <unistd.h>
#include "rnr/rnrconfig.h"
#include "rnr/log.h"
#include "rnr/opts.h"
#include "rnr/i2c-dev.h"
#include "rnr/i2c.h"
#include "version.h"

Go to the source code of this file.

Functions
static int	execRead (i2c_t *pI2C, int addr, int readlen)
	Execute I2C slave device read. More...
static void	MainInit (int argc, char *argv[], i2c_t *pI2C)
	Command initialization. More...
int	main (int argc, char *argv[])
	i2cread main() More...

Variables
static char *	Argv0
	command namve
static int	OptVerbose = 0
	verbose option
static char *	OptDevName = "/dev/i2c/0"
	i2c bus device option
static int	OptDevFd = -1
	opened i2c bus dev option
static int	OptI2CAddr = -1
	slave device address option
static int	OptI2CReadCount = 1
	read byte count option
static OptsPgmInfo_T	I2CReadPgmInfo
	Program Information. More...
static OptsInfo_T	I2CReadOptsInfo []
	Command Line Options Information.

Detailed Description

Read an I2C device.

LastChangedDate

2011-09-12 16:08:28 -0600 (Mon, 12 Sep 2011)

Rev

1279

Author

Robin Knight (robin.nosp@m..kni.nosp@m.ght@r.nosp@m.oadn.nosp@m.arrow.nosp@m.s.co.nosp@m.m)

Copyright

© 2007-2017. RoadNarrows LLC.
http://www.roadnarrows.com
All Rights Reserved

Definition in file i2cread.c.

Function Documentation

static int execRead ( i2c_t *  pI2C, int  addr, int  readlen  )

static

Execute I²C slave device read.

Parameters

pI2C	Pointer to I2C handle.
addr	Slave device address.
readlen	Number of bytes to read.

Returns

Returns number of bytes read ≥ 0 on success, -1 on failure.

Definition at line 177 of file i2cread.c.

References Argv0, i2c_read(), and OptVerbose.

Referenced by main().

{
  int     i;
  byte_t  readbuf[1024];

  if( readlen > sizeof(readbuf) )
  {
    readlen = sizeof(readbuf);
    fprintf(stderr, 
        "%s: Warning: %d: I2C read length too long. Resetting to %u]\n",
        Argv0, readlen, (uint_t)sizeof(readbuf));
  }

  if( OptVerbose )
  {
    printf("%s Reading 0x%02x for %d bytes...\n", Argv0, (byte_t)addr, readlen);
  }

  readlen = i2c_read(pI2C, (i2c_addr_t)addr, readbuf, (uint_t)readlen);

  if( readlen < 0 )
  {
    LOGSYSERROR("i2c_read()");
    return RC_ERROR;
  }

  if( OptVerbose )
  {
    printf("Read %d bytes: ", readlen);
  }
  for(i=0; i<readlen; ++i)
  {
    printf("0x%02x ", readbuf[i]);
  }
  if( (readlen > 0) || OptVerbose )
  {
    printf("\n");
  }

  return readlen;
}

int main	(	int	argc,
		char *	argv[]
	)

i2cread main()

Parameters

argc	Count of command-line options and arguments.
argv	Array of command-line options and arguments.

Returns

Exit value.

Definition at line 286 of file i2cread.c.

References execRead(), MainInit(), OptI2CAddr, and OptI2CReadCount.

{
  i2c_t i2c;
  int   rc;

  MainInit(argc, argv, &i2c);

  rc = execRead(&i2c, OptI2CAddr, OptI2CReadCount);

  return rc > 0? 0: (rc == 0? 1: 2);
}

static void MainInit ( int  argc, char *  argv[], i2c_t *  pI2C  )

static

Command initialization.

Parameters

argc	Command-line argument count.
argv	Command-line arguments.
pI2C	Pointer to I2C handle.

Definition at line 226 of file i2cread.c.

References i2c_struct::addr, Argv0, i2c_struct::fd, I2C_ADDR_DEV_HIGH, I2C_ADDR_DEV_LOW, i2c_open(), I2CReadOptsInfo, I2CReadPgmInfo, OptDevFd, OptDevName, OptI2CAddr, OptVerbose, and PkgInfo.

Referenced by main().

{
  // Name of this process
  Argv0 = basename(argv[0]);

  // Get the environment
  //EnvGet();

  // Parse input arguments
  argv = OptsGet(Argv0, &PkgInfo, &I2CReadPgmInfo, I2CReadOptsInfo, true,
                 &argc, argv);

  // Final option checks
  if( OptI2CAddr < 0x00 )
  {
    fprintf(stderr, "%s: Address option required\n", Argv0);
    exit(EC_BAD_OPT);
  }
  else if( (OptI2CAddr < I2C_ADDR_DEV_LOW) || (OptI2CAddr > I2C_ADDR_DEV_HIGH) )
  {
    fprintf(stderr, "%s: Address out of range: 0x%x\n", Argv0, OptI2CAddr);
    exit(EC_BAD_OPT);
  }

  // Opened device specified
  if( OptDevFd >= 0 )
  {
    pI2C->fd    = OptDevFd;
    pI2C->addr  = (ushort_t)(-1);
  }

  // I2C Bus device specified
  else
  {
    if( OptDevName == NULL || OptDevName[0] == 0 )
    {
      OptDevName = "/dev/i2c/0";
    }

    if( OptVerbose )
    {
      printf("I2C device: %s\n\n", OptDevName);
    }
  
    if( i2c_open(pI2C, OptDevName) < 0 )
    {
     LOGSYSERROR("%s: Failed to open.", OptDevName);
     exit(EC_ERROR);
    }
  }
}

Variable Documentation

OptsPgmInfo_T I2CReadPgmInfo

static

Initial value:

=
{
  .usage_args = "--address <addr>",

  .synopsis = "Read <count> bytes from an I2C device.",

  .long_desc = 
    "The %P command attempts to read <count> bytes from the specified I2C "
    "device. All read bytes are printed to stdout in ASCII hex format.",

  .diagnostics = 
    "Exit status is 0 if <count> bytes are read, 1 otherwise. "
    "Exit status is >=2 if error(s) are encountered."
}

Program Information.

Definition at line 84 of file i2cread.c.

Referenced by MainInit().