coreboot-kgpe-d16/src/soc/rockchip/rk3288/software_i2c.c

134 lines
3.1 KiB
C

/*
* This file is part of the coreboot project.
*
* Copyright 2015 Google, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <device/mmio.h>
#include <console/console.h>
#include <device/i2c_simple.h>
#include <gpio.h>
#include <soc/grf.h>
#include <soc/i2c.h>
#include <soc/pmu.h>
static struct {
gpio_t scl;
gpio_t sda;
} pins[] = {
[0]{.scl = GPIO(0, C, 0), .sda = GPIO(0, B, 7)},
[1]{.scl = GPIO(8, A, 5), .sda = GPIO(8, A, 4)},
[2]{.scl = GPIO(6, B, 2), .sda = GPIO(6, B, 1)},
[3]{.scl = GPIO(2, C, 0), .sda = GPIO(2, C, 1)},
[4]{.scl = GPIO(7, C, 2), .sda = GPIO(7, C, 1)},
[5]{.scl = GPIO(7, C, 4), .sda = GPIO(7, C, 3)},
};
static int get_scl(unsigned int bus)
{
return gpio_get(pins[bus].scl);
}
static int get_sda(unsigned int bus)
{
return gpio_get(pins[bus].sda);
}
static void set_scl(unsigned int bus, int high)
{
if (high)
gpio_input_pullup(pins[bus].scl);
else
gpio_output(pins[bus].scl, 0);
}
static void set_sda(unsigned int bus, int high)
{
if (high)
gpio_input_pullup(pins[bus].sda);
else
gpio_output(pins[bus].sda, 0);
}
static struct software_i2c_ops rk_ops = {
.get_scl = get_scl,
.get_sda = get_sda,
.set_scl = set_scl,
.set_sda = set_sda,
};
void software_i2c_attach(unsigned int bus)
{
software_i2c[bus] = &rk_ops;
/* Mux pins to GPIO function for software I2C emulation. */
switch (bus) {
case 0:
clrbits32(&rk3288_pmu->iomux_i2c0scl, IOMUX_I2C0SCL);
clrbits32(&rk3288_pmu->iomux_i2c0sda, IOMUX_I2C0SDA);
break;
case 1:
write32(&rk3288_grf->iomux_i2c1, IOMUX_GPIO(IOMUX_I2C1));
break;
case 2:
write32(&rk3288_grf->iomux_i2c2, IOMUX_GPIO(IOMUX_I2C2));
break;
case 3:
write32(&rk3288_grf->iomux_i2c3, IOMUX_GPIO(IOMUX_I2C3));
break;
case 4:
write32(&rk3288_grf->iomux_i2c4, IOMUX_GPIO(IOMUX_I2C4));
break;
case 5:
write32(&rk3288_grf->iomux_i2c5scl, IOMUX_GPIO(IOMUX_I2C5SCL));
write32(&rk3288_grf->iomux_i2c5sda, IOMUX_GPIO(IOMUX_I2C5SDA));
break;
default:
die("Unknown I2C bus number!");
}
/* Initialize bus to idle state. */
set_scl(bus, 1);
set_sda(bus, 1);
}
void software_i2c_detach(unsigned int bus)
{
software_i2c[bus] = NULL;
/* Mux pins back to hardware I2C controller. */
switch (bus) {
case 0:
setbits32(&rk3288_pmu->iomux_i2c0scl, IOMUX_I2C0SCL);
setbits32(&rk3288_pmu->iomux_i2c0sda, IOMUX_I2C0SDA);
break;
case 1:
write32(&rk3288_grf->iomux_i2c1, IOMUX_I2C1);
break;
case 2:
write32(&rk3288_grf->iomux_i2c2, IOMUX_I2C2);
break;
case 3:
write32(&rk3288_grf->iomux_i2c3, IOMUX_I2C3);
break;
case 4:
write32(&rk3288_grf->iomux_i2c4, IOMUX_I2C4);
break;
case 5:
write32(&rk3288_grf->iomux_i2c5scl, IOMUX_I2C5SCL);
write32(&rk3288_grf->iomux_i2c5sda, IOMUX_I2C5SDA);
break;
default:
die("Unknown I2C bus number!");
}
}