The I2C slave API has been present since 1.12 but lacked documentation on the behavior of its functions. Provide that, and revise existing documentation to make clear the type and mode of the device passed to each API call. Documented behavior is derived primarily from the LPC11U6X implementation, as the STM32 implementation generally ignores return values. Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
801 lines
24 KiB
C
801 lines
24 KiB
C
/**
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* @file
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*
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* @brief Public APIs for the I2C drivers.
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*/
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/*
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* Copyright (c) 2015 Intel Corporation
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#ifndef ZEPHYR_INCLUDE_DRIVERS_I2C_H_
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#define ZEPHYR_INCLUDE_DRIVERS_I2C_H_
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/**
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* @brief I2C Interface
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* @defgroup i2c_interface I2C Interface
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* @ingroup io_interfaces
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* @{
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*/
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#include <zephyr/types.h>
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#include <device.h>
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#ifdef __cplusplus
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extern "C" {
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#endif
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/*
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* The following #defines are used to configure the I2C controller.
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*/
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/** I2C Standard Speed: 100 kHz */
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#define I2C_SPEED_STANDARD (0x1U)
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/** I2C Fast Speed: 400 kHz */
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#define I2C_SPEED_FAST (0x2U)
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/** I2C Fast Plus Speed: 1 MHz */
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#define I2C_SPEED_FAST_PLUS (0x3U)
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/** I2C High Speed: 3.4 MHz */
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#define I2C_SPEED_HIGH (0x4U)
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/** I2C Ultra Fast Speed: 5 MHz */
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#define I2C_SPEED_ULTRA (0x5U)
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#define I2C_SPEED_SHIFT (1U)
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#define I2C_SPEED_SET(speed) (((speed) << I2C_SPEED_SHIFT) \
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& I2C_SPEED_MASK)
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#define I2C_SPEED_MASK (0x7U << I2C_SPEED_SHIFT) /* 3 bits */
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#define I2C_SPEED_GET(cfg) (((cfg) & I2C_SPEED_MASK) \
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>> I2C_SPEED_SHIFT)
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/** Use 10-bit addressing. DEPRECATED - Use I2C_MSG_ADDR_10_BITS instead. */
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#define I2C_ADDR_10_BITS BIT(0)
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/** Controller to act as Master. */
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#define I2C_MODE_MASTER BIT(4)
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/*
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* I2C_MSG_* are I2C Message flags.
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*/
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/** Write message to I2C bus. */
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#define I2C_MSG_WRITE (0U << 0U)
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/** Read message from I2C bus. */
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#define I2C_MSG_READ BIT(0)
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/** @cond INTERNAL_HIDDEN */
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#define I2C_MSG_RW_MASK BIT(0)
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/** @endcond */
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/** Send STOP after this message. */
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#define I2C_MSG_STOP BIT(1)
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/** RESTART I2C transaction for this message.
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*
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* @note Not all I2C drivers have or require explicit support for this
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* feature. Some drivers require this be present on a read message
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* that follows a write, or vice-versa. Some drivers will merge
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* adjacent fragments into a single transaction using this flag; some
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* will not. */
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#define I2C_MSG_RESTART BIT(2)
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/** Use 10-bit addressing for this message.
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*
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* @note Not all SoC I2C implementations support this feature. */
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#define I2C_MSG_ADDR_10_BITS BIT(3)
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/**
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* @brief One I2C Message.
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*
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* This defines one I2C message to transact on the I2C bus.
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*
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* @note Some of the configurations supported by this API may not be
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* supported by specific SoC I2C hardware implementations, in
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* particular features related to bus transactions intended to read or
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* write data from different buffers within a single transaction.
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* Invocations of i2c_transfer() may not indicate an error when an
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* unsupported configuration is encountered. In some cases drivers
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* will generate separate transactions for each message fragment, with
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* or without presence of @ref I2C_MSG_RESTART in #flags.
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*/
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struct i2c_msg {
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/** Data buffer in bytes */
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uint8_t *buf;
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/** Length of buffer in bytes */
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uint32_t len;
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/** Flags for this message */
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uint8_t flags;
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};
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/**
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* @cond INTERNAL_HIDDEN
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*
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* These are for internal use only, so skip these in
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* public documentation.
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*/
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struct i2c_slave_config;
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typedef int (*i2c_api_configure_t)(const struct device *dev,
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uint32_t dev_config);
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typedef int (*i2c_api_full_io_t)(const struct device *dev,
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struct i2c_msg *msgs,
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uint8_t num_msgs,
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uint16_t addr);
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typedef int (*i2c_api_slave_register_t)(const struct device *dev,
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struct i2c_slave_config *cfg);
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typedef int (*i2c_api_slave_unregister_t)(const struct device *dev,
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struct i2c_slave_config *cfg);
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typedef int (*i2c_api_recover_bus_t)(const struct device *dev);
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__subsystem struct i2c_driver_api {
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i2c_api_configure_t configure;
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i2c_api_full_io_t transfer;
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i2c_api_slave_register_t slave_register;
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i2c_api_slave_unregister_t slave_unregister;
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i2c_api_recover_bus_t recover_bus;
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};
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typedef int (*i2c_slave_api_register_t)(const struct device *dev);
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typedef int (*i2c_slave_api_unregister_t)(const struct device *dev);
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struct i2c_slave_driver_api {
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i2c_slave_api_register_t driver_register;
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i2c_slave_api_unregister_t driver_unregister;
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};
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/**
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* @endcond
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*/
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/** Slave device responds to 10-bit addressing. */
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#define I2C_SLAVE_FLAGS_ADDR_10_BITS BIT(0)
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/** @brief Function called when a write to the device is initiated.
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*
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* This function is invoked by the controller when the bus completes a
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* start condition for a write operation to the address associated
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* with a particular device.
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*
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* A success return shall cause the controller to ACK the next byte
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* received. An error return shall cause the controller to NACK the
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* next byte received.
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*
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* @param config the configuration structure associated with the
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* device to which the operation is addressed.
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*
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* @return 0 if the write is accepted, or a negative error code.
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*/
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typedef int (*i2c_slave_write_requested_cb_t)(
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struct i2c_slave_config *config);
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/** @brief Function called when a write to the device is continued.
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*
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* This function is invoked by the controller when it completes
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* reception of a byte of data in an ongoing write operation to the
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* device.
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*
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* A success return shall cause the controller to ACK the next byte
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* received. An error return shall cause the controller to NACK the
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* next byte received.
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*
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* @param config the configuration structure associated with the
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* device to which the operation is addressed.
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*
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* @param val the byte received by the controller.
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*
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* @return 0 if more data can be accepted, or a negative error
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* code.
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*/
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typedef int (*i2c_slave_write_received_cb_t)(
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struct i2c_slave_config *config, uint8_t val);
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/** @brief Function called when a read from the device is initiated.
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*
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* This function is invoked by the controller when the bus completes a
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* start condition for a read operation from the address associated
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* with a particular device.
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*
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* The value returned in @p *val will be transmitted. A success
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* return shall cause the controller to react to additional read
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* operations. An error return shall cause the controller to ignore
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* bus operations until a new start condition is received.
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*
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* @param config the configuration structure associated with the
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* device to which the operation is addressed.
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*
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* @param val pointer to storage for the first byte of data to return
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* for the read request.
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*
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* @return 0 if more data can be requested, or a negative error code.
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*/
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typedef int (*i2c_slave_read_requested_cb_t)(
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struct i2c_slave_config *config, uint8_t *val);
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/** @brief Function called when a read from the device is continued.
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*
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* This function is invoked by the controller when the bus is ready to
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* provide additional data for a read operation from the address
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* associated with the device device.
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*
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* The value returned in @p *val will be transmitted. A success
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* return shall cause the controller to react to additional read
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* operations. An error return shall cause the controller to ignore
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* bus operations until a new start condition is received.
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*
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* @param config the configuration structure associated with the
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* device to which the operation is addressed.
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*
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* @param val pointer to storage for the next byte of data to return
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* for the read request.
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*
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* @return 0 if data has been provided, or a negative error code.
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*/
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typedef int (*i2c_slave_read_processed_cb_t)(
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struct i2c_slave_config *config, uint8_t *val);
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/** @brief Function called when a stop condition is observed after a
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* start condition addressed to a particular device.
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*
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* This function is invoked by the controller when the bus is ready to
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* provide additional data for a read operation from the address
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* associated with the device device. After the function returns the
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* controller shall enter a state where it is ready to react to new
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* start conditions.
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*
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* @param config the configuration structure associated with the
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* device to which the operation is addressed.
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*
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* @return Ignored.
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*/
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typedef int (*i2c_slave_stop_cb_t)(struct i2c_slave_config *config);
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/** @brief Structure providing callbacks to be implemented for devices
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* that supports the I2C slave API.
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*
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* This structure may be shared by multiple devices that implement the
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* same API at different addresses on the bus.
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*/
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struct i2c_slave_callbacks {
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i2c_slave_write_requested_cb_t write_requested;
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i2c_slave_read_requested_cb_t read_requested;
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i2c_slave_write_received_cb_t write_received;
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i2c_slave_read_processed_cb_t read_processed;
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i2c_slave_stop_cb_t stop;
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};
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/** @brief Structure describing a device that supports the I2C
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* slave API.
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*
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* Instances of this are passed to the i2c_slave_register() and
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* i2c_slave_unregister() functions to indicate addition and removal
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* of a slave device, respective.
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*
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* Fields other than @c node must be initialized by the module that
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* implements the device behavior prior to passing the object
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* reference to i2c_slave_register().
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*/
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struct i2c_slave_config {
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/** Private, do not modify */
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sys_snode_t node;
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/** Flags for the slave device defined by I2C_SLAVE_FLAGS_* constants */
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uint8_t flags;
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/** Address for this slave device */
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uint16_t address;
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/** Callback functions */
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const struct i2c_slave_callbacks *callbacks;
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};
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/**
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* @brief Configure operation of a host controller.
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*
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* @param dev Pointer to the device structure for the driver instance.
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* @param dev_config Bit-packed 32-bit value to the device runtime configuration
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* for the I2C controller.
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*
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* @retval 0 If successful.
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* @retval -EIO General input / output error, failed to configure device.
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*/
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__syscall int i2c_configure(const struct device *dev, uint32_t dev_config);
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static inline int z_impl_i2c_configure(const struct device *dev,
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uint32_t dev_config)
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{
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const struct i2c_driver_api *api =
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(const struct i2c_driver_api *)dev->api;
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return api->configure(dev, dev_config);
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}
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/**
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* @brief Perform data transfer to another I2C device in master mode.
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*
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* This routine provides a generic interface to perform data transfer
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* to another I2C device synchronously. Use i2c_read()/i2c_write()
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* for simple read or write.
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*
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* The array of message @a msgs must not be NULL. The number of
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* message @a num_msgs may be zero,in which case no transfer occurs.
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*
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* @note Not all scatter/gather transactions can be supported by all
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* drivers. As an example, a gather write (multiple consecutive
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* `i2c_msg` buffers all configured for `I2C_MSG_WRITE`) may be packed
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* into a single transaction by some drivers, but others may emit each
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* fragment as a distinct write transaction, which will not produce
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* the same behavior. See the documentation of `struct i2c_msg` for
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* limitations on support for multi-message bus transactions.
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*
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* @param dev Pointer to the device structure for an I2C controller
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* driver configured in master mode.
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* @param msgs Array of messages to transfer.
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* @param num_msgs Number of messages to transfer.
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* @param addr Address of the I2C target device.
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*
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* @retval 0 If successful.
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* @retval -EIO General input / output error.
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*/
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__syscall int i2c_transfer(const struct device *dev,
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struct i2c_msg *msgs, uint8_t num_msgs,
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uint16_t addr);
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static inline int z_impl_i2c_transfer(const struct device *dev,
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struct i2c_msg *msgs, uint8_t num_msgs,
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uint16_t addr)
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{
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const struct i2c_driver_api *api =
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(const struct i2c_driver_api *)dev->api;
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return api->transfer(dev, msgs, num_msgs, addr);
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}
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/**
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* @brief Recover the I2C bus
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*
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* Attempt to recover the I2C bus.
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*
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* @param dev Pointer to the device structure for an I2C controller
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* driver configured in master mode.
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* @retval 0 If successful
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* @retval -EBUSY If bus is not clear after recovery attempt.
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* @retval -EIO General input / output error.
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* @retval -ENOTSUP If bus recovery is not supported
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*/
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__syscall int i2c_recover_bus(const struct device *dev);
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static inline int z_impl_i2c_recover_bus(const struct device *dev)
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{
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const struct i2c_driver_api *api =
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(const struct i2c_driver_api *)dev->api;
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if (api->recover_bus == NULL) {
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return -ENOTSUP;
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}
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return api->recover_bus(dev);
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}
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/**
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* @brief Registers the provided config as Slave device of a controller.
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*
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* Enable I2C slave mode for the 'dev' I2C bus driver using the provided
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* 'config' struct containing the functions and parameters to send bus
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* events. The I2C slave will be registered at the address provided as 'address'
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* struct member. Addressing mode - 7 or 10 bit - depends on the 'flags'
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* struct member. Any I2C bus events related to the slave mode will be passed
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* onto I2C slave device driver via a set of callback functions provided in
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* the 'callbacks' struct member.
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*
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* Most of the existing hardware allows simultaneous support for master
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* and slave mode. This is however not guaranteed.
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*
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* @param dev Pointer to the device structure for an I2C controller
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* driver configured in slave mode.
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* @param cfg Config struct with functions and parameters used by the I2C driver
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* to send bus events
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*
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* @retval 0 Is successful
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* @retval -EINVAL If parameters are invalid
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* @retval -EIO General input / output error.
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* @retval -ENOTSUP If slave mode is not supported
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*/
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static inline int i2c_slave_register(const struct device *dev,
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struct i2c_slave_config *cfg)
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{
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const struct i2c_driver_api *api =
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(const struct i2c_driver_api *)dev->api;
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if (api->slave_register == NULL) {
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return -ENOTSUP;
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}
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return api->slave_register(dev, cfg);
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}
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/**
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* @brief Unregisters the provided config as Slave device
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*
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* This routine disables I2C slave mode for the 'dev' I2C bus driver using
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* the provided 'config' struct containing the functions and parameters
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* to send bus events.
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*
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* @param dev Pointer to the device structure for an I2C controller
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* driver configured in slave mode.
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* @param cfg Config struct with functions and parameters used by the I2C driver
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* to send bus events
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*
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* @retval 0 Is successful
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* @retval -EINVAL If parameters are invalid
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* @retval -ENOTSUP If slave mode is not supported
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*/
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static inline int i2c_slave_unregister(const struct device *dev,
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struct i2c_slave_config *cfg)
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{
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const struct i2c_driver_api *api =
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(const struct i2c_driver_api *)dev->api;
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if (api->slave_unregister == NULL) {
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return -ENOTSUP;
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}
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return api->slave_unregister(dev, cfg);
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}
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/**
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* @brief Instructs the I2C Slave device to register itself to the I2C Controller
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*
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* This routine instructs the I2C Slave device to register itself to the I2C
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* Controller via its parent controller's i2c_slave_register() API.
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*
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* @param dev Pointer to the device structure for the I2C slave
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* device (not itself an I2C controller).
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*
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* @retval 0 Is successful
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* @retval -EINVAL If parameters are invalid
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* @retval -EIO General input / output error.
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*/
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__syscall int i2c_slave_driver_register(const struct device *dev);
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static inline int z_impl_i2c_slave_driver_register(const struct device *dev)
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{
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const struct i2c_slave_driver_api *api =
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(const struct i2c_slave_driver_api *)dev->api;
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return api->driver_register(dev);
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}
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/**
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* @brief Instructs the I2C Slave device to unregister itself from the I2C
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* Controller
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*
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* This routine instructs the I2C Slave device to unregister itself from the I2C
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* Controller via its parent controller's i2c_slave_register() API.
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*
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* @param dev Pointer to the device structure for the I2C slave
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* device (not itself an I2C controller).
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*
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* @retval 0 Is successful
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* @retval -EINVAL If parameters are invalid
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*/
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__syscall int i2c_slave_driver_unregister(const struct device *dev);
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static inline int z_impl_i2c_slave_driver_unregister(const struct device *dev)
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{
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const struct i2c_slave_driver_api *api =
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(const struct i2c_slave_driver_api *)dev->api;
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return api->driver_unregister(dev);
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}
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/*
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* Derived i2c APIs -- all implemented in terms of i2c_transfer()
|
|
*/
|
|
|
|
/**
|
|
* @brief Write a set amount of data to an I2C device.
|
|
*
|
|
* This routine writes a set amount of data synchronously.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param buf Memory pool from which the data is transferred.
|
|
* @param num_bytes Number of bytes to write.
|
|
* @param addr Address to the target I2C device for writing.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_write(const struct device *dev, const uint8_t *buf,
|
|
uint32_t num_bytes, uint16_t addr)
|
|
{
|
|
struct i2c_msg msg;
|
|
|
|
msg.buf = (uint8_t *)buf;
|
|
msg.len = num_bytes;
|
|
msg.flags = I2C_MSG_WRITE | I2C_MSG_STOP;
|
|
|
|
return i2c_transfer(dev, &msg, 1, addr);
|
|
}
|
|
|
|
/**
|
|
* @brief Read a set amount of data from an I2C device.
|
|
*
|
|
* This routine reads a set amount of data synchronously.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param buf Memory pool that stores the retrieved data.
|
|
* @param num_bytes Number of bytes to read.
|
|
* @param addr Address of the I2C device being read.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_read(const struct device *dev, uint8_t *buf,
|
|
uint32_t num_bytes, uint16_t addr)
|
|
{
|
|
struct i2c_msg msg;
|
|
|
|
msg.buf = buf;
|
|
msg.len = num_bytes;
|
|
msg.flags = I2C_MSG_READ | I2C_MSG_STOP;
|
|
|
|
return i2c_transfer(dev, &msg, 1, addr);
|
|
}
|
|
|
|
/**
|
|
* @brief Write then read data from an I2C device.
|
|
*
|
|
* This supports the common operation "this is what I want", "now give
|
|
* it to me" transaction pair through a combined write-then-read bus
|
|
* transaction.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param addr Address of the I2C device
|
|
* @param write_buf Pointer to the data to be written
|
|
* @param num_write Number of bytes to write
|
|
* @param read_buf Pointer to storage for read data
|
|
* @param num_read Number of bytes to read
|
|
*
|
|
* @retval 0 if successful
|
|
* @retval negative on error.
|
|
*/
|
|
static inline int i2c_write_read(const struct device *dev, uint16_t addr,
|
|
const void *write_buf, size_t num_write,
|
|
void *read_buf, size_t num_read)
|
|
{
|
|
struct i2c_msg msg[2];
|
|
|
|
msg[0].buf = (uint8_t *)write_buf;
|
|
msg[0].len = num_write;
|
|
msg[0].flags = I2C_MSG_WRITE;
|
|
|
|
msg[1].buf = (uint8_t *)read_buf;
|
|
msg[1].len = num_read;
|
|
msg[1].flags = I2C_MSG_RESTART | I2C_MSG_READ | I2C_MSG_STOP;
|
|
|
|
return i2c_transfer(dev, msg, 2, addr);
|
|
}
|
|
|
|
/**
|
|
* @brief Read multiple bytes from an internal address of an I2C device.
|
|
*
|
|
* This routine reads multiple bytes from an internal address of an
|
|
* I2C device synchronously.
|
|
*
|
|
* Instances of this may be replaced by i2c_write_read().
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param dev_addr Address of the I2C device for reading.
|
|
* @param start_addr Internal address from which the data is being read.
|
|
* @param buf Memory pool that stores the retrieved data.
|
|
* @param num_bytes Number of bytes being read.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_burst_read(const struct device *dev,
|
|
uint16_t dev_addr,
|
|
uint8_t start_addr,
|
|
uint8_t *buf,
|
|
uint32_t num_bytes)
|
|
{
|
|
return i2c_write_read(dev, dev_addr,
|
|
&start_addr, sizeof(start_addr),
|
|
buf, num_bytes);
|
|
}
|
|
|
|
/**
|
|
* @brief Write multiple bytes to an internal address of an I2C device.
|
|
*
|
|
* This routine writes multiple bytes to an internal address of an
|
|
* I2C device synchronously.
|
|
*
|
|
* @warning The combined write synthesized by this API may not be
|
|
* supported on all I2C devices. Uses of this API may be made more
|
|
* portable by replacing them with calls to i2c_write() passing a
|
|
* buffer containing the combined address and data.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param dev_addr Address of the I2C device for writing.
|
|
* @param start_addr Internal address to which the data is being written.
|
|
* @param buf Memory pool from which the data is transferred.
|
|
* @param num_bytes Number of bytes being written.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_burst_write(const struct device *dev,
|
|
uint16_t dev_addr,
|
|
uint8_t start_addr,
|
|
const uint8_t *buf,
|
|
uint32_t num_bytes)
|
|
{
|
|
struct i2c_msg msg[2];
|
|
|
|
msg[0].buf = &start_addr;
|
|
msg[0].len = 1U;
|
|
msg[0].flags = I2C_MSG_WRITE;
|
|
|
|
msg[1].buf = (uint8_t *)buf;
|
|
msg[1].len = num_bytes;
|
|
msg[1].flags = I2C_MSG_WRITE | I2C_MSG_STOP;
|
|
|
|
return i2c_transfer(dev, msg, 2, dev_addr);
|
|
}
|
|
|
|
/**
|
|
* @brief Read internal register of an I2C device.
|
|
*
|
|
* This routine reads the value of an 8-bit internal register of an I2C
|
|
* device synchronously.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param dev_addr Address of the I2C device for reading.
|
|
* @param reg_addr Address of the internal register being read.
|
|
* @param value Memory pool that stores the retrieved register value.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_reg_read_byte(const struct device *dev,
|
|
uint16_t dev_addr,
|
|
uint8_t reg_addr, uint8_t *value)
|
|
{
|
|
return i2c_write_read(dev, dev_addr,
|
|
®_addr, sizeof(reg_addr),
|
|
value, sizeof(*value));
|
|
}
|
|
|
|
/**
|
|
* @brief Write internal register of an I2C device.
|
|
*
|
|
* This routine writes a value to an 8-bit internal register of an I2C
|
|
* device synchronously.
|
|
*
|
|
* @note This function internally combines the register and value into
|
|
* a single bus transaction.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param dev_addr Address of the I2C device for writing.
|
|
* @param reg_addr Address of the internal register being written.
|
|
* @param value Value to be written to internal register.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_reg_write_byte(const struct device *dev,
|
|
uint16_t dev_addr,
|
|
uint8_t reg_addr, uint8_t value)
|
|
{
|
|
uint8_t tx_buf[2] = {reg_addr, value};
|
|
|
|
return i2c_write(dev, tx_buf, 2, dev_addr);
|
|
}
|
|
|
|
/**
|
|
* @brief Update internal register of an I2C device.
|
|
*
|
|
* This routine updates the value of a set of bits from an 8-bit internal
|
|
* register of an I2C device synchronously.
|
|
*
|
|
* @note If the calculated new register value matches the value that
|
|
* was read this function will not generate a write operation.
|
|
*
|
|
* @param dev Pointer to the device structure for an I2C controller
|
|
* driver configured in master mode.
|
|
* @param dev_addr Address of the I2C device for updating.
|
|
* @param reg_addr Address of the internal register being updated.
|
|
* @param mask Bitmask for updating internal register.
|
|
* @param value Value for updating internal register.
|
|
*
|
|
* @retval 0 If successful.
|
|
* @retval -EIO General input / output error.
|
|
*/
|
|
static inline int i2c_reg_update_byte(const struct device *dev,
|
|
uint8_t dev_addr,
|
|
uint8_t reg_addr, uint8_t mask,
|
|
uint8_t value)
|
|
{
|
|
uint8_t old_value, new_value;
|
|
int rc;
|
|
|
|
rc = i2c_reg_read_byte(dev, dev_addr, reg_addr, &old_value);
|
|
if (rc != 0) {
|
|
return rc;
|
|
}
|
|
|
|
new_value = (old_value & ~mask) | (value & mask);
|
|
if (new_value == old_value) {
|
|
return 0;
|
|
}
|
|
|
|
return i2c_reg_write_byte(dev, dev_addr, reg_addr, new_value);
|
|
}
|
|
|
|
/**
|
|
* @brief Dump out an I2C message
|
|
*
|
|
* Dumps out a list of I2C messages. For any that are writes (W), the data is
|
|
* displayed in hex.
|
|
*
|
|
* It looks something like this (with name "testing"):
|
|
*
|
|
* D: I2C msg: testing, addr=56
|
|
* D: W len=01:
|
|
* D: contents:
|
|
* D: 06 |.
|
|
* D: W len=0e:
|
|
* D: contents:
|
|
* D: 00 01 02 03 04 05 06 07 |........
|
|
* D: 08 09 0a 0b 0c 0d |......
|
|
*
|
|
* @param name Name of this dump, displayed at the top.
|
|
* @param msgs Array of messages to dump.
|
|
* @param num_msgs Number of messages to dump.
|
|
* @param addr Address of the I2C target device.
|
|
*/
|
|
void i2c_dump_msgs(const char *name, const struct i2c_msg *msgs,
|
|
uint8_t num_msgs, uint16_t addr);
|
|
|
|
struct i2c_client_config {
|
|
char *i2c_master;
|
|
uint16_t i2c_addr;
|
|
};
|
|
|
|
#define I2C_DECLARE_CLIENT_CONFIG struct i2c_client_config i2c_client
|
|
|
|
#define I2C_CLIENT(_master, _addr) \
|
|
.i2c_client = { \
|
|
.i2c_master = (_master), \
|
|
.i2c_addr = (_addr), \
|
|
}
|
|
|
|
#define I2C_GET_MASTER(_conf) ((_conf)->i2c_client.i2c_master)
|
|
#define I2C_GET_ADDR(_conf) ((_conf)->i2c_client.i2c_addr)
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
#include <syscalls/i2c.h>
|
|
|
|
#endif /* ZEPHYR_INCLUDE_DRIVERS_I2C_H_ */
|