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 

    31 typedef struct SMBusEEPROMDevice {

    32     SMBusDevice dev;

    33     uint8_t *data;

    34     uint8_t offset;

    35 } SMBusEEPROMDevice;

    36 

    37 static 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 

    44 static 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 

    54 static uint8_t eeprom_receive_byte(SMBusDevice *dev)

    55 {

    56     SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;

    57     uint8_t val = eeprom->data[eeprom->offset++];

    58 #ifdef DEBUG

    59     printf("eeprom_receive_byte: addr=0x%02x val=0x%02x\n",

    60            dev->i2c.address, val);

    61 #endif

    62     return val;

    63 }

    64 

    65 static void eeprom_write_data(SMBusDevice *dev, uint8_t cmd, uint8_t *buf, int len)

    66 {

    67     SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;

    68     int n;

    69 #ifdef DEBUG

    70     printf("eeprom_write_byte: addr=0x%02x cmd=0x%02x val=0x%02x\n",

    71            dev->i2c.address, cmd, buf[0]);

    72 #endif

    73     /* An page write operation is not a valid SMBus command.

    74        It is a block write without a length byte.  Fortunately we

    75        get the full block anyway.  */

    76     /* TODO: Should this set the current location?  */

    77     if (cmd + len > 256)

    78         n = 256 - cmd;

    79     else

    80         n = len;

    81     memcpy(eeprom->data + cmd, buf, n);

    82     len -= n;

    83     if (len)

    84         memcpy(eeprom->data, buf + n, len);

    85 }

    86 

    87 static uint8_t eeprom_read_data(SMBusDevice *dev, uint8_t cmd, int n)

    88 {

    89     SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev;

    90     /* If this is the first byte then set the current position.  */

    91     if (n == 0)

    92         eeprom->offset = cmd;

    93     /* As with writes, we implement block reads without the

    94        SMBus length byte.  */

    95     return eeprom_receive_byte(dev);

    96 }

    97 

    98 void smbus_eeprom_device_init(i2c_bus *bus, uint8_t addr, uint8_t *buf)

    99 {

   100     SMBusEEPROMDevice *eeprom;

   101 

   102     eeprom = (SMBusEEPROMDevice *)smbus_device_init(bus, addr,

   103         sizeof(SMBusEEPROMDevice));

   104 

   105     eeprom->dev.quick_cmd = eeprom_quick_cmd;

   106     eeprom->dev.send_byte = eeprom_send_byte;

   107     eeprom->dev.receive_byte = eeprom_receive_byte;

   108     eeprom->dev.write_data = eeprom_write_data;

   109     eeprom->dev.read_data = eeprom_read_data;

   110     eeprom->data = buf;

   111     eeprom->offset = 0;

   112 }