Import of the watch repository from Pebble

src/fw/drivers/i2c.h

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+/*
+ * Copyright 2024 Google LLC
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include "board/board.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+
+//! Start using the I2C bus to which \a slave is connected
+//! Must be called before any other reads or writes to the slave are performed
+//! @param slave    I2C slave reference, which will identify the bus to use
+void i2c_use(I2CSlavePort *slave);
+
+//! Stop using the I2C bus to which \a slave is connected
+//! Call when done communicating with the slave
+//! @param slave    I2C slave reference, which will identify the bus to release
+void i2c_release(I2CSlavePort *slave);
+
+//! Reset the slave
+//! Will cycle the power to and re-initialize the bus to which \a slave is connected, if this is
+//! supported for the bus.
+//! @param slave    I2C slave reference, which will identify the bus to be reset
+void i2c_reset(I2CSlavePort *slave);
+
+//! Manually bang out the clock on the bus to which \a slave is connected until the data line
+//! recovers for a period or we timeout waiting for it to recover
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave    I2C slave reference, which will identify the bus to be recovered
+//! @return true if the data line recovered, false otherwise
+bool i2c_bitbang_recovery(I2CSlavePort *slave);
+
+//! Read the value of a register
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave                I2C slave to communicate with
+//! @param register_address     Address of register to read
+//! @param result               Pointer to destination buffer
+//! @return true if transfer succeeded, false if error occurred
+bool i2c_read_register(I2CSlavePort *slave, uint8_t register_address, uint8_t *result);
+
+//! Read a sequence of registers starting from \a register_address_start
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave                    I2C slave to communicate with
+//! @param register_address_start   Address of first register to read
+//! @param read_size                Number of bytes to read
+//! @param result_buffer            Pointer to destination buffer
+//! @return true if transfer succeeded, false if error occurred
+bool i2c_read_register_block(I2CSlavePort *slave, uint8_t register_address_start,
+                             uint32_t read_size, uint8_t* result_buffer);
+
+//! Read a block of data without sending a register address before doing so.
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave                    I2C slave to communicate with
+//! @param read_size                Number of bytes to read
+//! @param result_buffer            Pointer to destination buffer
+//! @return true if transfer succeeded, false if error occurred
+bool i2c_read_block(I2CSlavePort *slave, uint32_t read_size, uint8_t* result_buffer);
+
+//! Write to a register
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave                I2C slave to communicate with
+//! @param register_address     Address of register to write to
+//! @param value                Data value to write
+//! @return true if transfer succeeded, false if error occurred
+bool i2c_write_register(I2CSlavePort *slave, uint8_t register_address, uint8_t value);
+
+//! Write to a sequence of registers starting from \a register_address_start
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave                    I2C slave to communicate with
+//! @param register_address_start   Address of first register to read
+//! @param write_size               Number of bytes to write
+//! @param buffer                   Pointer to source buffer
+//! @return true if transfer succeeded, false if error occurred
+bool i2c_write_register_block(I2CSlavePort *slave, uint8_t register_address_start,
+                              uint32_t write_size, const uint8_t* buffer);
+
+//! Write a block of data without sending a register address before doing so.
+//! Must not be called before \ref i2c_use has been called for the slave
+//! @param slave                    I2C slave to communicate with
+//! @param write_size               Number of bytes to write
+//! @param buffer                   Pointer to source buffer
+//! @return true if transfer succeeded, false if error occurred
+bool i2c_write_block(I2CSlavePort *slave, uint32_t write_size, const uint8_t* buffer);