LXR qemu/hw/smbus

   1/*
   2 * QEMU SMBus EEPROM device
   3 *
   4 * Copyright (c) 2007 Arastra, Inc.
   5 *
   6 * Permission is hereby granted, free of charge, to any person obtaining a copy
   7 * of this software and associated documentation files (the "Software"), to deal
   8 * in the Software without restriction, including without limitation the rights
   9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 * copies of the Software, and to permit persons to whom the Software is
  11 * furnished to do so, subject to the following conditions:
  12 *
  13 * The above copyright notice and this permission notice shall be included in
  14 * all copies or substantial portions of the Software.
  15 *
  16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 * THE SOFTWARE.
  23 */
  24
  25#include "hw.h"
  26#include "i2c.h"
  27#include "smbus.h"
  28
  29//#define DEBUG
  30
  31typedef struct SMBusEEPROMDevice {
  32    SMBusDevice smbusdev;
  33    void *data;
  34    uint8_t offset;
  35} SMBusEEPROMDevice;
  36
  37static void eeprom_quick_cmd(SMBusDevice *dev, uint8_t read)
  38{
  39#ifdef DEBUG
  40    printf("eeprom_quick_cmd: addr=0x%02x read=%d\n", dev->i2c.address, read);
  41#endif
  42}
  43
  44static void eeprom_send_byte(SMBusDevice *dev, uint8_t val)
  45{
  46    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  47#ifdef DEBUG
  48    printf("eeprom_send_byte: addr=0x%02x val=0x%02x\n",
  49           dev->i2c.address, val);
  50#endif
  51    eeprom->offset = val;
  52}
  53
  54static uint8_t eeprom_receive_byte(SMBusDevice *dev)
  55{
  56    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  57    uint8_t *data = eeprom->data;
  58    uint8_t val = data[eeprom->offset++];
  59#ifdef DEBUG
  60    printf("eeprom_receive_byte: addr=0x%02x val=0x%02x\n",
  61           dev->i2c.address, val);
  62#endif
  63    return val;
  64}
  65
  66static void eeprom_write_data(SMBusDevice *dev, uint8_t cmd, uint8_t *buf, int len)
  67{
  68    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  69    int n;
  70#ifdef DEBUG
  71    printf("eeprom_write_byte: addr=0x%02x cmd=0x%02x val=0x%02x\n",
  72           dev->i2c.address, cmd, buf[0]);
  73#endif
  74    /* An page write operation is not a valid SMBus command.
  75       It is a block write without a length byte.  Fortunately we
  76       get the full block anyway.  */
  77    /* TODO: Should this set the current location?  */
  78    if (cmd + len > 256)
  79        n = 256 - cmd;
  80    else
  81        n = len;
  82    memcpy(eeprom->data + cmd, buf, n);
  83    len -= n;
  84    if (len)
  85        memcpy(eeprom->data, buf + n, len);
  86}
  87
  88static uint8_t eeprom_read_data(SMBusDevice *dev, uint8_t cmd, int n)
  89{
  90    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  91    /* If this is the first byte then set the current position.  */
  92    if (n == 0)
  93        eeprom->offset = cmd;
  94    /* As with writes, we implement block reads without the
  95       SMBus length byte.  */
  96    return eeprom_receive_byte(dev);
  97}
  98
  99static int smbus_eeprom_init(SMBusDevice *dev)
 100{
 101    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *)dev;
 102
 103    eeprom->offset = 0;
 104    return 0;
 105}
 106
 107static SMBusDeviceInfo smbus_eeprom_info = {
 108    .i2c.qdev.name = "smbus-eeprom",
 109    .i2c.qdev.size = sizeof(SMBusEEPROMDevice),
 110    .i2c.qdev.props = (Property[]) {
 111        DEFINE_PROP_PTR("data", SMBusEEPROMDevice, data),
 112        DEFINE_PROP_END_OF_LIST(),
 113    },
 114    .init = smbus_eeprom_init,
 115    .quick_cmd = eeprom_quick_cmd,
 116    .send_byte = eeprom_send_byte,
 117    .receive_byte = eeprom_receive_byte,
 118    .write_data = eeprom_write_data,
 119    .read_data = eeprom_read_data
 120};
 121
 122static void smbus_eeprom_register_devices(void)
 123{
 124    smbus_register_device(&smbus_eeprom_info);
 125}
 126
 127device_init(smbus_eeprom_register_devices)
 128