qemu/include/hw/i2c/smbus_slave.h
Corey Minyard 9cf27d74a8 i2c:smbus: Simplify write operation
There were two different write functions and the SMBus code kept
track of the command.

Keeping track of the command wasn't useful, in fact it wasn't quite
correct for the eeprom_smbus code.  And there is no need for two write
functions.  Just have one write function and the first byte in the
buffer is the command.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
2019-02-27 21:06:08 -06:00

80 lines
2.9 KiB
C

/*
* QEMU SMBus device (slave) API
*
* Copyright (c) 2007 Arastra, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef HW_SMBUS_SLAVE_H
#define HW_SMBUS_SLAVE_H
#include "hw/i2c/i2c.h"
#define TYPE_SMBUS_DEVICE "smbus-device"
#define SMBUS_DEVICE(obj) \
OBJECT_CHECK(SMBusDevice, (obj), TYPE_SMBUS_DEVICE)
#define SMBUS_DEVICE_CLASS(klass) \
OBJECT_CLASS_CHECK(SMBusDeviceClass, (klass), TYPE_SMBUS_DEVICE)
#define SMBUS_DEVICE_GET_CLASS(obj) \
OBJECT_GET_CLASS(SMBusDeviceClass, (obj), TYPE_SMBUS_DEVICE)
typedef struct SMBusDevice SMBusDevice;
typedef struct SMBusDeviceClass
{
I2CSlaveClass parent_class;
/*
* An operation with no data, special in SMBus.
* This may be NULL, quick commands are ignore in that case.
*/
void (*quick_cmd)(SMBusDevice *dev, uint8_t read);
uint8_t (*receive_byte)(SMBusDevice *dev);
/*
* We can't distinguish between a word write and a block write with
* length 1, so pass the whole data block including the length byte
* (if present). The device is responsible figuring out what type of
* command this is.
* This may be NULL if no data is written to the device. Writes
* will be ignore in that case.
*/
int (*write_data)(SMBusDevice *dev, uint8_t *buf, uint8_t len);
/* Likewise we can't distinguish between different reads, or even know
the length of the read until the read is complete, so read data a
byte at a time. The device is responsible for adding the length
byte on block reads. */
uint8_t (*read_data)(SMBusDevice *dev, int n);
} SMBusDeviceClass;
struct SMBusDevice {
/* The SMBus protocol is implemented on top of I2C. */
I2CSlave i2c;
/* Remaining fields for internal use only. */
int mode;
int data_len;
uint8_t data_buf[34]; /* command + len + 32 bytes of data. */
};
#endif