mirror of
https://github.com/Telecominfraproject/OpenCellular.git
synced 2025-12-31 11:01:19 +00:00
a81f0cd547
Implement a generalized I2C transmit-receive function that write-then-read blocks of raw data. Original 8-bit and 16-bit read/write functions are refactored. SMBus read-block protocol for ASCII string is also implemented based on this API. Signed-off-by: Rong Chang <rongchang@chromium.org> BUG=chrome-os-partner:8026,8316 TEST=manual: Type 'lightsaber' to check 8-bit read/write. Type 'charger' to check 16-bit read. Type 'charger input 4032' to check 16-bit write. Change-Id: I0ad3ad45b796d9ec03d8fbc1d643aa6a92d6343f
52 lines
1.8 KiB
C
52 lines
1.8 KiB
C
/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
|
|
* Use of this source code is governed by a BSD-style license that can be
|
|
* found in the LICENSE file.
|
|
*/
|
|
|
|
/* I2C interface for Chrome EC */
|
|
|
|
#ifndef __CROS_EC_I2C_H
|
|
#define __CROS_EC_I2C_H
|
|
|
|
#include "common.h"
|
|
|
|
/* Flags for slave address field, in addition to the 8-bit address */
|
|
#define I2C_FLAG_BIG_ENDIAN 0x100 /* 16 byte values are MSB-first */
|
|
|
|
/* Initializes the module. */
|
|
int i2c_init(void);
|
|
|
|
/* Reads a 16-bit register from the slave at 8-bit slave address
|
|
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
|
|
* space. */
|
|
int i2c_read16(int port, int slave_addr, int offset, int* data);
|
|
|
|
/* Writes a 16-bit register to the slave at 8-bit slave address
|
|
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
|
|
* space. */
|
|
int i2c_write16(int port, int slave_addr, int offset, int data);
|
|
|
|
/* Reads an 8-bit register from the slave at 8-bit slave address
|
|
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
|
|
* space. */
|
|
int i2c_read8(int port, int slave_addr, int offset, int* data);
|
|
|
|
/* Writes an 8-bit register to the slave at 8-bit slave address
|
|
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
|
|
* space. */
|
|
int i2c_write8(int port, int slave_addr, int offset, int data);
|
|
|
|
/* Read ascii string using smbus read block protocol.
|
|
* Read bytestream from <slaveaddr>:<offset> with format:
|
|
* [length_N] [byte_0] [byte_1] ... [byte_N-1]
|
|
*
|
|
* <len> : the max length of receving buffer. to read N bytes
|
|
* ascii, len should be at least N+1 to include the
|
|
* terminating 0.
|
|
* <len> == 0 : buffer size > 255
|
|
*/
|
|
int i2c_read_string(int port, int slave_addr, int offset, uint8_t *data,
|
|
int len);
|
|
|
|
#endif /* __CROS_EC_I2C_H */
|