diff options
Diffstat (limited to 'src/soc/rockchip/rk3288/software_i2c.c')
| -rw-r--r-- | src/soc/rockchip/rk3288/software_i2c.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/src/soc/rockchip/rk3288/software_i2c.c b/src/soc/rockchip/rk3288/software_i2c.c new file mode 100644 index 0000000000..a71fcd16bf --- /dev/null +++ b/src/soc/rockchip/rk3288/software_i2c.c @@ -0,0 +1,137 @@ +/* + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA + */ + +#include <arch/io.h> +#include <console/console.h> +#include <device/i2c.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 bus) +{ + return gpio_get(pins[bus].scl); +} + +static int get_sda(unsigned bus) +{ + return gpio_get(pins[bus].sda); +} + +static void set_scl(unsigned bus, int high) +{ + if (high) + gpio_input_pullup(pins[bus].scl); + else + gpio_output(pins[bus].scl, 0); +} + +static void set_sda(unsigned 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 bus) +{ + software_i2c[bus] = &rk_ops; + + /* Mux pins to GPIO function for software I2C emulation. */ + switch (bus) { + case 0: + clrbits_le32(&rk3288_pmu->iomux_i2c0scl, IOMUX_I2C0SCL); + clrbits_le32(&rk3288_pmu->iomux_i2c0sda, IOMUX_I2C0SDA); + break; + case 1: + writel(IOMUX_GPIO(IOMUX_I2C1), &rk3288_grf->iomux_i2c1); + break; + case 2: + writel(IOMUX_GPIO(IOMUX_I2C2), &rk3288_grf->iomux_i2c2); + break; + case 3: + writel(IOMUX_GPIO(IOMUX_I2C3), &rk3288_grf->iomux_i2c3); + break; + case 4: + writel(IOMUX_GPIO(IOMUX_I2C4), &rk3288_grf->iomux_i2c4); + break; + case 5: + writel(IOMUX_GPIO(IOMUX_I2C5SCL), &rk3288_grf->iomux_i2c5scl); + writel(IOMUX_GPIO(IOMUX_I2C5SDA), &rk3288_grf->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 bus) +{ + software_i2c[bus] = NULL; + + /* Mux pins back to hardware I2C controller. */ + switch (bus) { + case 0: + setbits_le32(&rk3288_pmu->iomux_i2c0scl, IOMUX_I2C0SCL); + setbits_le32(&rk3288_pmu->iomux_i2c0sda, IOMUX_I2C0SDA); + break; + case 1: + writel(IOMUX_I2C1, &rk3288_grf->iomux_i2c1); + break; + case 2: + writel(IOMUX_I2C2, &rk3288_grf->iomux_i2c2); + break; + case 3: + writel(IOMUX_I2C3, &rk3288_grf->iomux_i2c3); + break; + case 4: + writel(IOMUX_I2C4, &rk3288_grf->iomux_i2c4); + break; + case 5: + writel(IOMUX_I2C5SCL, &rk3288_grf->iomux_i2c5scl); + writel(IOMUX_I2C5SDA, &rk3288_grf->iomux_i2c5sda); + break; + default: + die("Unknown I2C bus number!"); + } +} |