/* Zipit poweroff tool. 
 * (c) 2005 Chris Studholme
 * GPL
 */

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h> 
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include "i2c-dev.h"


static int i2c_open(int i2cbus) {
  char filename1[32];
  char filename2[32];
  char filename3[32];
  int e1,e2,e3;
  int file;

  /*
   * Try all three variants and give the correct error message
   * upon failure
   */

  sprintf(filename1,"/dev/i2c-%d",i2cbus);
  sprintf(filename2,"/dev/i2c%d",i2cbus);
  sprintf(filename3,"/dev/i2c/%d",i2cbus);
  if ((file = open(filename1,O_RDWR)) < 0) {
    e1 = errno;
    if ((file = open(filename2,O_RDWR)) < 0) {
      e2 = errno;
      if ((file = open(filename3,O_RDWR)) < 0) {
        e3 = errno;
        if(e1 == ENOENT && e2 == ENOENT && e3 == ENOENT) {
          fprintf(stderr,"Error: Could not open file `%s', `%s', or `%s': %s\n",
		  filename1,filename2,filename3,strerror(ENOENT));
        }
        if (e1 != ENOENT) {
          fprintf(stderr,"Error: Could not open file `%s' : %s\n",
		  filename1,strerror(e1));
          if(e1 == EACCES)
            fprintf(stderr,"Run as root?\n");
        }
        if (e2 != ENOENT) {
          fprintf(stderr,"Error: Could not open file `%s' : %s\n",
		  filename2,strerror(e2));
          if(e2 == EACCES)
            fprintf(stderr,"Run as root?\n");
        }
        if (e3 != ENOENT) {
          fprintf(stderr,"Error: Could not open file `%s' : %s\n",
		  filename3,strerror(e3));
          if(e3 == EACCES)
            fprintf(stderr,"Run as root?\n");
        }
	return -1;
      } else {
	//filename = filename3;
      }
    } else {
      //filename = filename2;
    }
  } else {
    //filename = filename1;
  }
  return file;
}

 
int main(int argc, char **argv) {

  if (argc<2 || (strcmp(argv[1],"-p")!=0 && strcmp(argv[1],"-r")!=0)) {
    printf("Usage:\n");
    printf("  poweroff-zipit [ -p | -r ]\n");
    return 1;
  }

  int i2cbus = 0;
  int address = 0x55;

  int file = i2c_open(i2cbus);
  if (file==-1) {
    return 1;
  }

  /* use FORCE so that we can look at registers even when
     a driver is also running */
  if (ioctl(file,I2C_SLAVE_FORCE,address) < 0) {
    fprintf(stderr,"Error: Could not set address to %d: %s\n",address,
            strerror(errno));
    return 1;
  }

  if (strcmp(argv[1],"-p")==0)
    i2c_smbus_read_byte_data(file,0x81);
  else if (strcmp(argv[1],"-r")==0)
    i2c_smbus_read_byte_data(file,0x84);
  
  close(file);
  return 0;
}