blob: 3be9c4dd3e0d56b6592216ffbd64a8a3a7863e9b (
plain) (
tree)
|
|
/**************************************************************************
*
* Copyright (c) 2013 Alcatel-Lucent
*
* Alcatel Lucent licenses this file to You under the Apache License,
* Version 2.0 (the "License"); you may not use this file except in
* compliance with the License. A copy of the License is contained the
* file LICENSE at the top level of this repository.
* You may also 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.
*
**************************************************************************
*
* i2c.h:
*
* Header for I-Squared-C code.
*
* Original author: Ed Sutter (ed.sutter@alcatel-lucent.com)
*
*/
#ifndef _I2C_H_
#define _I2C_H_
extern int i2cVerbose;
/********************************************************************
*
* Commands used by i2cCtrl():
*/
#define I2CCTRL_INIT 1
#define I2CCTRL_SHOW 2
#define I2CCTRL_START 3 /* Send START condition */
#define I2CCTRL_STOP 4 /* Send STOP condition */
#define I2CCTRL_WADD 5 /* Send Write address */
#define I2CCTRL_RADD 6 /* Send Read address */
#define I2CCTRL_RDAT 7 /* Read data */
#define I2CCTRL_WDAT 8 /* Write data */
#define I2CCTRL_SACK 9 /* Send ACK */
#define I2CCTRL_WACK 10 /* WaitFor ACK */
/********************************************************************
*
* Upper bits of the bigaddr integer used for special case read/write
*/
#define REPEATED_START 0x40000000
#define OMIT_STOP 0x20000000
/********************************************************************
*
* Functions that must be provided from some target-specific code.
*/
/* i2cCtrl()
* Parameters:
* int interface-
* This parameter supports the case where the target hardware has more
* than one i2c controller. The interface number would correspond to
* one of potentially several different controllers.
* int cmd-
* Command to be carried out by the control function.
* ulong arg1-
* First command-specific argument.
* ulong arg2-
* Second command-specific argument.
*/
extern int i2cCtrl(int interface,int cmd,unsigned long arg1,unsigned long arg2);
/* i2cRead()
* Parameters:
* int interface-
* See description under i2cCtrl.
* int bigaddr-
* The device address on the I2C bus. Referred to here as "big" because
* it is an "int" so it supports 10-bit addresses (if needed).
* uchar *data-
* Pointer to the data buffer into which the data is to be placed.
* int len-
* Number of bytes to be read from the I2C device. This must not be
* larger than the size of the data buffer.
* Return:
* int
* The function should return the number of bytes read. If everything
* went well, then the return value should equal the len parameter.
* Negative represents some failure.
*/
extern int i2cRead(int interface,int bigaddr,unsigned char *data,int len);
/* i2cWrite()
* Parameters:
* int interface-
* See description under i2cCtrl.
* int bigaddr-
* See description under i2cRead.
* uchar *data-
* Buffer from which the data is to be taken and put into the specified
* I2C device.
* int len-
* Number of bytes to be written.
* Return:
* int
* The function should return the number of bytes written. If everything
* went well, then the return value should equal the len parameter.
* Negative represents some failure.
*/
extern int i2cWrite(int interface,int bigaddr,unsigned char *data,int len);
/* i2cShow()
* Parameters:
* int interface-
* See description under i2cCtrl.
* Return:
* void
* The function should be part of target-specific code that simply
* prints out a list of the device names and their address on the
* I-Squared-C bus of the specfied interface.
*/
extern void i2cShow(int interface);
#endif
|
