From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ben Warren <biggerbadderben@gmail.com>
Date: Wed, 30 Jan 2008 11:33:56 -0500
Subject: [U-Boot-Users] MPC8xx I2C
Message-ID: <47A0A6F4.4010402@gmail.com>
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To: u-boot@lists.denx.de

Hi,

I'm trying to rationalize some very common I2C code and came across the 
following:

Every controller except cpu/mpc8xx implements functions like this:

---

uchar i2c_reg_read(uchar i2c_addr, uchar reg)
{
	uchar buf;

	i2c_read(i2c_addr, reg, 1, &buf, 1);
	return buf;
}

void i2c_reg_write(uchar i2c_addr, uchar reg, uchar val)
{
	i2c_write(i2c_addr, reg, 1, &val, 1);
}


---

cpu/mpc8xx, however, adds i2c_init() calls:

---

uchar i2c_reg_read(uchar i2c_addr, uchar reg)
{
	uchar buf;

	i2c_init(CFG_I2C_SPEED, CFG_I2C_SLAVE);
	i2c_read(i2c_addr, reg, 1, &buf, 1);
	return (buf);
}

void i2c_reg_write(uchar i2c_addr, uchar reg, uchar val)
{
	i2c_init(CFG_I2C_SPEED, CFG_I2C_SLAVE);
	i2c_write(i2c_addr, reg, 1, &val, 1);
}

---

Can somebody lend historical perspective as to why these i2c_init() 
calls are needed?

thanks,
Ben