| /* i2c.h - public I2C driver API */ |
| |
| /* |
| * Copyright (c) 2015 Intel Corporation |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| #ifndef __DRIVERS_I2C_H |
| #define __DRIVERS_I2C_H |
| |
| /** |
| * @brief I2C Interface |
| * @defgroup i2c_interface I2C Interface |
| * @ingroup io_interfaces |
| * @{ |
| */ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| #include <stdint.h> |
| #include <device.h> |
| |
| /* I2C speeds */ |
| #define I2C_SPEED_STANDARD (0x1) |
| #define I2C_SPEED_FAST (0x2) |
| #define I2C_SPEED_FAST_PLUS (0x3) |
| #define I2C_SPEED_HIGH (0x4) |
| #define I2C_SPEED_ULTRA (0x5) |
| |
| /* I2C dev_config bitfields */ |
| #define I2C_ADDR_10_BITS (1 << 0) |
| #define I2C_SPEED_MASK (0x7 << 1) /* 3 bits */ |
| #define I2C_MODE_MASTER (1 << 4) |
| #define I2C_MODE_SLAVE_READ (1 << 5) |
| |
| /* I2C Message Flags */ |
| #define I2C_MSG_WRITE (0 << 0) |
| #define I2C_MSG_READ (1 << 0) |
| #define I2C_MSG_RW_MASK (1 << 0) |
| |
| /* STOP I2C transaction (drive should take care of this) */ |
| #define I2C_MSG_STOP (1 << 1) |
| /* RESTART I2C transaction */ |
| #define I2C_MSG_RESTART (1 << 2) |
| |
| struct i2c_msg { |
| /* Data buffer in bytes */ |
| uint8_t *buf; |
| |
| /* Length of buffer in bytes */ |
| uint32_t len; |
| |
| /* Flags for this message */ |
| uint8_t flags; |
| }; |
| |
| union dev_config { |
| uint32_t raw; |
| struct { |
| uint32_t use_10_bit_addr : 1; |
| uint32_t speed : 3; |
| uint32_t is_master_device : 1; |
| uint32_t is_slave_read : 1; |
| uint32_t reserved : 26; |
| } bits; |
| }; |
| |
| enum i2c_cb_type { |
| I2C_CB_WRITE = 1, |
| I2C_CB_READ = 2, |
| I2C_CB_ERROR = 3, |
| }; |
| |
| typedef int (*i2c_api_configure_t)(struct device *dev, |
| uint32_t dev_config); |
| typedef int (*i2c_api_full_io_t)(struct device *dev, |
| struct i2c_msg *msgs, |
| uint8_t num_msgs, |
| uint16_t addr); |
| typedef int (*i2c_api_suspend_t)(struct device *dev); |
| typedef int (*i2c_api_resume_t)(struct device *dev); |
| |
| struct i2c_driver_api { |
| i2c_api_configure_t configure; |
| i2c_api_full_io_t transfer; |
| i2c_api_suspend_t suspend; |
| i2c_api_resume_t resume; |
| }; |
| |
| /** |
| * @brief Configure a host controllers operation |
| * |
| * @param dev Pointer to the device structure for the driver instance |
| * @param dev_config Bit-packed 32-bit value to the device runtime configuration |
| * for the I2C controller. |
| * |
| * @return DEV_OK if successful, another DEV_* code otherwise. |
| */ |
| static inline int i2c_configure(struct device *dev, uint32_t dev_config) |
| { |
| struct i2c_driver_api *api; |
| |
| api = (struct i2c_driver_api *)dev->driver_api; |
| return api->configure(dev, dev_config); |
| } |
| |
| /** |
| * @brief Write a set amount of data to an I2C device |
| * |
| * The function is synchronous. |
| * |
| * @param dev Pointer to the device structure for the driver instance |
| * @param buf Memory pool that data should be transferred from |
| * @param len Size of the memory pool available for reading from |
| * @param addr Address of the I2C device to write to |
| * |
| * @return DEV_OK if successful, another DEV_* code otherwise. |
| */ |
| static inline int i2c_write(struct device *dev, uint8_t *buf, |
| uint32_t len, uint16_t addr) |
| { |
| struct i2c_driver_api *api; |
| struct i2c_msg msg; |
| |
| msg.buf = buf; |
| msg.len = len; |
| msg.flags = I2C_MSG_WRITE | I2C_MSG_STOP; |
| |
| api = (struct i2c_driver_api *)dev->driver_api; |
| return api->transfer(dev, &msg, 1, addr); |
| } |
| |
| /** |
| * @brief Read a set amount of data from an I2C device |
| * |
| * The function is synchronous. |
| * |
| * @param dev Pointer to the device structure for the driver instance |
| * @param buf Memory pool that data should be transferred to |
| * @param len Size of the memory pool available for writing to |
| * @param addr Address of the I2C device to read from |
| * |
| * @return DEV_OK if successful, another DEV_* code otherwise. |
| */ |
| static inline int i2c_read(struct device *dev, uint8_t *buf, |
| uint32_t len, uint16_t addr) |
| { |
| struct i2c_driver_api *api; |
| struct i2c_msg msg; |
| |
| msg.buf = buf; |
| msg.len = len; |
| msg.flags = I2C_MSG_READ | I2C_MSG_STOP; |
| |
| api = (struct i2c_driver_api *)dev->driver_api; |
| return api->transfer(dev, &msg, 1, addr); |
| } |
| |
| /** |
| * @brief Performs data transfer to another I2C device |
| * |
| * This provides a generic interface to perform data transfer |
| * to another I2C device. If a simple read or write is needed, |
| * use i2c_read()/i2c_write() instead. The function is synchronous. |
| * |
| * @param dev Pointer to the device structure for the driver instance |
| * @param msgs Array of messages |
| * @param num_msgs Number of messages |
| * @param addr Address of the I2C target device |
| * |
| * @return DEV_OK if successful, another DEV_* code otherwise. |
| */ |
| static inline int i2c_transfer(struct device *dev, |
| struct i2c_msg *msgs, uint8_t num_msgs, |
| uint16_t addr) |
| { |
| struct i2c_driver_api *api; |
| |
| api = (struct i2c_driver_api *)dev->driver_api; |
| return api->transfer(dev, msgs, num_msgs, addr); |
| } |
| |
| /** |
| * @brief Suspend an I2C driver |
| * @param dev Pointer to the device structure for the driver instance |
| * |
| * @return DEV_OK |
| */ |
| static inline int i2c_suspend(struct device *dev) |
| { |
| struct i2c_driver_api *api; |
| |
| api = (struct i2c_driver_api *)dev->driver_api; |
| return api->suspend(dev); |
| } |
| |
| /** |
| * @brief Resume an I2C driver |
| * @param dev Pointer to the device structure for the driver instance |
| * |
| * @return DEV_OK |
| */ |
| static inline int i2c_resume(struct device *dev) |
| { |
| struct i2c_driver_api *api; |
| |
| api = (struct i2c_driver_api *)dev->driver_api; |
| return api->resume(dev); |
| } |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| /** |
| * @} |
| */ |
| |
| |
| #endif /* __DRIVERS_I2C_H */ |