Function start_cond

src/device/software_i2c.c:72–102

}

static int start_cond(unsigned int bus)
{
	spew("software_i2c(%d): Sending start condition... ", bus);

	/* SDA might not yet be high if repeated start. */
	software_i2c[bus]->set_sda(bus, 1);
	wait(bus);

	/* Might need to wait for clock stretching if repeated start. */
	software_i2c[bus]->set_scl(bus, 1);
	if (wait_for_scl(bus, "before start condition"))
		return ERR_TIMEOUT;
	wait(bus);	/* Repeated start setup time, minimum 4.7us */

	if (!software_i2c[bus]->get_sda(bus)) {
		printk(BIOS_ERR, "software_i2c(%d): Arbitration lost trying "
			"to send start condition!\n", bus);
		return ERR_ARB;
	}

	/* SCL is high, transition SDA low as first part of start condition. */
	software_i2c[bus]->set_sda(bus, 0);
	wait(bus);
	assert(software_i2c[bus]->get_scl(bus));

	/* Pull SCL low to finish start condition (next pulse will be data). */
	software_i2c[bus]->set_scl(bus, 0);

	spew("Start condition transmitted!\n");
	return 0;
}

static int stop_cond(unsigned int bus)
{