#include "project.h"


#ifndef SLIM

#define GPIO_SCL GPIOB
#define GPIO_SDA GPIOB
#define SCL 	GPIO13
#define SDA	GPIO14

#define I2C_BB_DELAY do { delay_us(1); } while (0)

int
i2c_bb (int scl, int sda)
{
  if (scl)
    gpio_set (GPIO_SCL, SCL);
  else
    gpio_clear (GPIO_SCL, SCL);
  if (sda)
    gpio_set (GPIO_SDA, SDA);
  else
    gpio_clear (GPIO_SDA, SDA);

  return ! !(gpio_get (GPIO_SDA, SDA) & SDA);

}


void
i2c_bb_start (void)
{
  i2c_bb (1, 1);
  I2C_BB_DELAY;
  i2c_bb (1, 0);
  I2C_BB_DELAY;
  i2c_bb (0, 0);
  I2C_BB_DELAY;
}


void
i2c_bb_stop (void)
{
  i2c_bb (0, 0);
  I2C_BB_DELAY;
  i2c_bb (1, 0);
  I2C_BB_DELAY;
  i2c_bb (1, 1);
  I2C_BB_DELAY;
}

int
i2c_bb_send_data (uint8_t v)
{
  int c;


  for (c = 0x80; c; c >>= 1)
    {
      i2c_bb (0, c & v);
      I2C_BB_DELAY;
      i2c_bb (1, c & v);
      I2C_BB_DELAY;
      i2c_bb (0, c & v);
      I2C_BB_DELAY;
    }

  i2c_bb (0, 1);
  I2C_BB_DELAY;
  i2c_bb (1, 1);
  I2C_BB_DELAY;
  c = i2c_bb (1, 1);
  i2c_bb (0, 1);

  return c;
}


int
i2c_bb_start_transaction (uint8_t a, int wnr)
{
  int ret;

  i2c_bb_start ();
  ret = i2c_bb_send_data (a << 1 | ! !(wnr));


  return ret;
}

#if 0
void
i2c_bb_scan (void)
{
  int i, r;

  return;
  i2cp_reset ();

  printf ("Probing bus\r\n");
  for (i = 0; i < 128; ++i)
    {
      while (i2cp_lock ());
      i2cp_start ();
      i2cp_abort_start ();
      i2cp_stop ();
      i2cp_abort_stop ();
      r = i2cp_start_transaction (i, I2C_WRITE);
      i2cp_stop ();
      i2cp_unlock ();
      if (!r)
        printf ("Found device at address 0x%x\r\n", i);
      usart1_drain ();
    }
  printf ("Done\r\n");
  i2cp_reset ();

}
#endif

void
i2c_bb_init (void)
{
  gpio_set_mode (GPIO_SCL, GPIO_MODE_OUTPUT_50_MHZ,
                 GPIO_CNF_OUTPUT_OPENDRAIN, SCL);
  gpio_set_mode (GPIO_SDA, GPIO_MODE_OUTPUT_50_MHZ,
                 GPIO_CNF_OUTPUT_OPENDRAIN, SDA);

  i2c_bb_start ();
  i2c_bb_stop ();


}
#endif