LXR qemu/hw/i2c/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 "qemu/osdep.h"
  26#include "hw/hw.h"
  27#include "hw/i2c/i2c.h"
  28#include "hw/i2c/smbus.h"
  29
  30//#define DEBUG
  31
  32typedef struct SMBusEEPROMDevice {
  33    SMBusDevice smbusdev;
  34    void *data;
  35    uint8_t offset;
  36} SMBusEEPROMDevice;
  37
  38static void eeprom_quick_cmd(SMBusDevice *dev, uint8_t read)
  39{
  40#ifdef DEBUG
  41    printf("eeprom_quick_cmd: addr=0x%02x read=%d\n", dev->i2c.address, read);
  42#endif
  43}
  44
  45static void eeprom_send_byte(SMBusDevice *dev, uint8_t val)
  46{
  47    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  48#ifdef DEBUG
  49    printf("eeprom_send_byte: addr=0x%02x val=0x%02x\n",
  50           dev->i2c.address, val);
  51#endif
  52    eeprom->offset = val;
  53}
  54
  55static uint8_t eeprom_receive_byte(SMBusDevice *dev)
  56{
  57    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  58    uint8_t *data = eeprom->data;
  59    uint8_t val = data[eeprom->offset++];
  60#ifdef DEBUG
  61    printf("eeprom_receive_byte: addr=0x%02x val=0x%02x\n",
  62           dev->i2c.address, val);
  63#endif
  64    return val;
  65}
  66
  67static void eeprom_write_data(SMBusDevice *dev, uint8_t cmd, uint8_t *buf, int len)
  68{
  69    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  70    int n;
  71#ifdef DEBUG
  72    printf("eeprom_write_byte: addr=0x%02x cmd=0x%02x val=0x%02x\n",
  73           dev->i2c.address, cmd, buf[0]);
  74#endif
  75    /* A page write operation is not a valid SMBus command.
  76       It is a block write without a length byte.  Fortunately we
  77       get the full block anyway.  */
  78    /* TODO: Should this set the current location?  */
  79    if (cmd + len > 256)
  80        n = 256 - cmd;
  81    else
  82        n = len;
  83    memcpy(eeprom->data + cmd, buf, n);
  84    len -= n;
  85    if (len)
  86        memcpy(eeprom->data, buf + n, len);
  87}
  88
  89static uint8_t eeprom_read_data(SMBusDevice *dev, uint8_t cmd, int n)
  90{
  91    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;
  92    /* If this is the first byte then set the current position.  */
  93    if (n == 0)
  94        eeprom->offset = cmd;
  95    /* As with writes, we implement block reads without the
  96       SMBus length byte.  */
  97    return eeprom_receive_byte(dev);
  98}
  99
 100static void smbus_eeprom_realize(DeviceState *dev, Error **errp)
 101{
 102    SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *)dev;
 103
 104    eeprom->offset = 0;
 105}
 106
 107static Property smbus_eeprom_properties[] = {
 108    DEFINE_PROP_PTR("data", SMBusEEPROMDevice, data),
 109    DEFINE_PROP_END_OF_LIST(),
 110};
 111
 112static void smbus_eeprom_class_initfn(ObjectClass *klass, void *data)
 113{
 114    DeviceClass *dc = DEVICE_CLASS(klass);
 115    SMBusDeviceClass *sc = SMBUS_DEVICE_CLASS(klass);
 116
 117    dc->realize = smbus_eeprom_realize;
 118    sc->quick_cmd = eeprom_quick_cmd;
 119    sc->send_byte = eeprom_send_byte;
 120    sc->receive_byte = eeprom_receive_byte;
 121    sc->write_data = eeprom_write_data;
 122    sc->read_data = eeprom_read_data;
 123    dc->props = smbus_eeprom_properties;
 124    /* Reason: pointer property "data" */
 125    dc->user_creatable = false;
 126}
 127
 128static const TypeInfo smbus_eeprom_info = {
 129    .name          = "smbus-eeprom",
 130    .parent        = TYPE_SMBUS_DEVICE,
 131    .instance_size = sizeof(SMBusEEPROMDevice),
 132    .class_init    = smbus_eeprom_class_initfn,
 133};
 134
 135static void smbus_eeprom_register_types(void)
 136{
 137    type_register_static(&smbus_eeprom_info);
 138}
 139
 140type_init(smbus_eeprom_register_types)
 141
 142void smbus_eeprom_init_one(I2CBus *smbus, uint8_t address, uint8_t *eeprom_buf)
 143{
 144    DeviceState *dev;
 145
 146    dev = qdev_create((BusState *) smbus, "smbus-eeprom");
 147    qdev_prop_set_uint8(dev, "address", address);
 148    qdev_prop_set_ptr(dev, "data", eeprom_buf);
 149    qdev_init_nofail(dev);
 150}
 151
 152void smbus_eeprom_init(I2CBus *smbus, int nb_eeprom,
 153                       const uint8_t *eeprom_spd, int eeprom_spd_size)
 154{
 155    int i;
 156    uint8_t *eeprom_buf = g_malloc0(8 * 256); /* XXX: make this persistent */
 157    if (eeprom_spd_size > 0) {
 158        memcpy(eeprom_buf, eeprom_spd, eeprom_spd_size);
 159    }
 160
 161    for (i = 0; i < nb_eeprom; i++) {
 162        smbus_eeprom_init_one(smbus, 0x50 + i, eeprom_buf + (i * 256));
 163    }
 164}
 165