root / hw / smbus_eeprom.c @ c75a823c
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/*
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* QEMU SMBus EEPROM device
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*
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* Copyright (c) 2007 Arastra, Inc.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "hw.h" |
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#include "i2c.h" |
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#include "smbus.h" |
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//#define DEBUG
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typedef struct SMBusEEPROMDevice { |
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SMBusDevice dev; |
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uint8_t *data; |
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uint8_t offset; |
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} SMBusEEPROMDevice; |
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static void eeprom_quick_cmd(SMBusDevice *dev, uint8_t read) |
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{ |
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#ifdef DEBUG
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printf("eeprom_quick_cmd: addr=0x%02x read=%d\n", dev->addr, read);
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#endif
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} |
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static void eeprom_send_byte(SMBusDevice *dev, uint8_t val) |
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{ |
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SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev; |
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#ifdef DEBUG
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printf("eeprom_send_byte: addr=0x%02x val=0x%02x\n", dev->addr, val);
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#endif
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eeprom->offset = val; |
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} |
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static uint8_t eeprom_receive_byte(SMBusDevice *dev)
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{ |
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SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev; |
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uint8_t val = eeprom->data[eeprom->offset++]; |
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#ifdef DEBUG
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printf("eeprom_receive_byte: addr=0x%02x val=0x%02x\n", dev->addr, val);
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#endif
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return val;
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} |
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static void eeprom_write_data(SMBusDevice *dev, uint8_t cmd, uint8_t *buf, int len) |
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{ |
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SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev; |
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int n;
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#ifdef DEBUG
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printf("eeprom_write_byte: addr=0x%02x cmd=0x%02x val=0x%02x\n", dev->addr,
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cmd, buf[0]);
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#endif
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/* An page write operation is not a valid SMBus command.
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It is a block write without a length byte. Fortunately we
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get the full block anyway. */
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/* TODO: Should this set the current location? */
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if (cmd + len > 256) |
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n = 256 - cmd;
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else
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n = len; |
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memcpy(eeprom->data + cmd, buf, n); |
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len -= n; |
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if (len)
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memcpy(eeprom->data, buf + n, len); |
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} |
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static uint8_t eeprom_read_data(SMBusDevice *dev, uint8_t cmd, int n) |
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{ |
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SMBusEEPROMDevice *eeprom = (SMBusEEPROMDevice *) dev; |
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/* If this is the first byte then set the current position. */
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if (n == 0) |
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eeprom->offset = cmd; |
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/* As with writes, we implement block reads without the
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SMBus length byte. */
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return eeprom_receive_byte(dev);
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} |
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void smbus_eeprom_device_init(i2c_bus *bus, uint8_t addr, uint8_t *buf)
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{ |
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SMBusEEPROMDevice *eeprom; |
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eeprom = (SMBusEEPROMDevice *)smbus_device_init(bus, addr, |
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sizeof(SMBusEEPROMDevice));
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eeprom->dev.quick_cmd = eeprom_quick_cmd; |
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eeprom->dev.send_byte = eeprom_send_byte; |
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eeprom->dev.receive_byte = eeprom_receive_byte; |
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eeprom->dev.write_data = eeprom_write_data; |
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eeprom->dev.read_data = eeprom_read_data; |
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eeprom->data = buf; |
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eeprom->offset = 0;
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} |