| /* |
| * Copyright (c) 2019 Antmicro <www.antmicro.com> |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| #define DT_DRV_COMPAT litex_i2c |
| |
| #include <zephyr/device.h> |
| #include <zephyr/drivers/i2c.h> |
| #include "i2c_bitbang.h" |
| |
| #include <soc.h> |
| |
| #define SCL_BIT_POS 0 |
| #define SDA_DIR_BIT_POS 1 |
| #define SDA_BIT_W_POS 2 |
| #define SDA_BIT_R_POS 0 |
| |
| #define SDA_DIR_OUTPUT 1 |
| #define SDA_DIR_INPUT 0 |
| |
| #define HIGH_STATE_ON_I2C_LINES 0x7 |
| |
| struct i2c_litex_cfg { |
| uint32_t write_addr; |
| uint32_t read_addr; |
| }; |
| |
| #define GET_I2C_CFG(dev) \ |
| ((const struct i2c_litex_cfg *) dev->config) |
| |
| #define GET_I2C_BITBANG(dev) \ |
| ((struct i2c_bitbang *) dev->data) |
| |
| static inline void set_bit(uint32_t addr, uint32_t bit, uint32_t val) |
| { |
| uint32_t mask = BIT(bit); |
| |
| if (val) { |
| litex_write8(litex_read8(addr) | mask, addr); |
| } else { |
| litex_write8(litex_read8(addr) & ~mask, addr); |
| } |
| } |
| |
| static inline int get_bit(uint32_t addr, uint32_t bit) |
| { |
| uint32_t mask = BIT(bit); |
| |
| return !!(litex_read8(addr) & mask); |
| } |
| |
| static void i2c_litex_bitbang_set_scl(void *context, int state) |
| { |
| const struct i2c_litex_cfg *config = |
| (const struct i2c_litex_cfg *) context; |
| |
| set_bit(config->write_addr, SCL_BIT_POS, state); |
| } |
| |
| static void i2c_litex_bitbang_set_sda(void *context, int state) |
| { |
| const struct i2c_litex_cfg *config = |
| (const struct i2c_litex_cfg *) context; |
| |
| set_bit(config->write_addr, SDA_DIR_BIT_POS, SDA_DIR_OUTPUT); |
| set_bit(config->write_addr, SDA_BIT_W_POS, state); |
| } |
| |
| static int i2c_litex_bitbang_get_sda(void *context) |
| { |
| const struct i2c_litex_cfg *config = |
| (const struct i2c_litex_cfg *) context; |
| |
| set_bit(config->write_addr, SDA_DIR_BIT_POS, SDA_DIR_INPUT); |
| return get_bit(config->read_addr, SDA_BIT_R_POS); |
| } |
| |
| static const struct i2c_bitbang_io i2c_litex_bitbang_io = { |
| .set_scl = i2c_litex_bitbang_set_scl, |
| .set_sda = i2c_litex_bitbang_set_sda, |
| .get_sda = i2c_litex_bitbang_get_sda, |
| }; |
| |
| static int i2c_litex_init(const struct device *dev) |
| { |
| const struct i2c_litex_cfg *config = GET_I2C_CFG(dev); |
| struct i2c_bitbang *bitbang = GET_I2C_BITBANG(dev); |
| |
| litex_write8(litex_read8(config->write_addr) | HIGH_STATE_ON_I2C_LINES, config->write_addr); |
| i2c_bitbang_init(bitbang, &i2c_litex_bitbang_io, (void *)config); |
| |
| return 0; |
| } |
| |
| static int i2c_litex_configure(const struct device *dev, uint32_t dev_config) |
| { |
| struct i2c_bitbang *bitbang = GET_I2C_BITBANG(dev); |
| |
| return i2c_bitbang_configure(bitbang, dev_config); |
| } |
| |
| static int i2c_litex_transfer(const struct device *dev, struct i2c_msg *msgs, |
| uint8_t num_msgs, uint16_t addr) |
| { |
| struct i2c_bitbang *bitbang = GET_I2C_BITBANG(dev); |
| |
| return i2c_bitbang_transfer(bitbang, msgs, num_msgs, addr); |
| } |
| |
| static const struct i2c_driver_api i2c_litex_driver_api = { |
| .configure = i2c_litex_configure, |
| .transfer = i2c_litex_transfer, |
| }; |
| |
| /* Device Instantiation */ |
| |
| #define I2C_LITEX_INIT(n) \ |
| static const struct i2c_litex_cfg i2c_litex_cfg_##n = { \ |
| .write_addr = DT_INST_REG_ADDR_BY_NAME(n, write), \ |
| .read_addr = DT_INST_REG_ADDR_BY_NAME(n, read), \ |
| }; \ |
| \ |
| static struct i2c_bitbang i2c_bitbang_##n; \ |
| \ |
| I2C_DEVICE_DT_INST_DEFINE(n, \ |
| i2c_litex_init, \ |
| NULL, \ |
| &i2c_bitbang_##n, \ |
| &i2c_litex_cfg_##n, \ |
| POST_KERNEL, \ |
| CONFIG_I2C_INIT_PRIORITY, \ |
| &i2c_litex_driver_api \ |
| ); |
| |
| DT_INST_FOREACH_STATUS_OKAY(I2C_LITEX_INIT) |