qemu/hw/smbus_eeprom.c

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/*
* QEMU SMBus EEPROM device
*
* 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.
*/
#include "hw.h"
#include "i2c.h"
#include "smbus.h"
//#define DEBUG
typedef struct SMBusEEPROMDevice {
SMBusDevice dev;
uint8_t *data;
uint8_t offset;
} SMBusEEPROMDevice;
static void eeprom_quick_cmd(SMBusDevice *dev, uint8_t read)
{
#ifdef DEBUG
printf("eeprom_quick_cmd: addr=0x%02x read=%d\n", dev->addr, read);
#endif
}
static void eeprom_send_byte(SMBusDevice *dev, uint8_t val)
{
SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
#ifdef DEBUG
printf("eeprom_send_byte: addr=0x%02x val=0x%02x\n", dev->addr, val);
#endif
eeprom->offset = val;
}
static uint8_t eeprom_receive_byte(SMBusDevice *dev)
{
SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
uint8_t val = eeprom->data[eeprom->offset++];
#ifdef DEBUG
printf("eeprom_receive_byte: addr=0x%02x val=0x%02x\n", dev->addr, val);
#endif
return val;
}
static void eeprom_write_data(SMBusDevice *dev, uint8_t cmd, uint8_t *buf, int len)
{
SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
int n;
#ifdef DEBUG
printf("eeprom_write_byte: addr=0x%02x cmd=0x%02x val=0x%02x\n", dev->addr,
cmd, buf[0]);
#endif
/* An page write operation is not a valid SMBus command.
It is a block write without a length byte. Fortunately we
get the full block anyway. */
/* TODO: Should this set the current location? */
if (cmd + len > 256)
n = 256 - cmd;
else
n = len;
memcpy(eeprom->data + cmd, buf, n);
len -= n;
if (len)
memcpy(eeprom->data, buf + n, len);
}
static uint8_t eeprom_read_data(SMBusDevice *dev, uint8_t cmd, int n)
{
SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
/* If this is the first byte then set the current position. */
if (n == 0)
eeprom->offset = cmd;
/* As with writes, we implement block reads without the
SMBus length byte. */
return eeprom_receive_byte(dev);
}
void smbus_eeprom_device_init(i2c_bus *bus, uint8_t addr, uint8_t *buf)
{
SMBusEEPROMDevice *eeprom;
eeprom = (SMBusEEPROMDevice *)smbus_device_init(bus, addr,
sizeof(SMBusEEPROMDevice));
eeprom->dev.quick_cmd = eeprom_quick_cmd;
eeprom->dev.send_byte = eeprom_send_byte;
eeprom->dev.receive_byte = eeprom_receive_byte;
eeprom->dev.write_data = eeprom_write_data;
eeprom->dev.read_data = eeprom_read_data;
eeprom->data = buf;
eeprom->offset = 0;
}