diff options
Diffstat (limited to 'drivers/i2c/chips')
| -rw-r--r-- | drivers/i2c/chips/eeprom.c | 39 |
1 files changed, 19 insertions, 20 deletions
diff --git a/drivers/i2c/chips/eeprom.c b/drivers/i2c/chips/eeprom.c index 213a9f98dec..9a81252a721 100644 --- a/drivers/i2c/chips/eeprom.c +++ b/drivers/i2c/chips/eeprom.c @@ -78,7 +78,7 @@ static struct i2c_driver eeprom_driver = { static void eeprom_update_client(struct i2c_client *client, u8 slice) { struct eeprom_data *data = i2c_get_clientdata(client); - int i, j; + int i; mutex_lock(&data->update_lock); @@ -93,15 +93,12 @@ static void eeprom_update_client(struct i2c_client *client, u8 slice) != 32) goto exit; } else { - if (i2c_smbus_write_byte(client, slice << 5)) { - dev_dbg(&client->dev, "eeprom read start has failed!\n"); - goto exit; - } - for (i = slice << 5; i < (slice + 1) << 5; i++) { - j = i2c_smbus_read_byte(client); - if (j < 0) + for (i = slice << 5; i < (slice + 1) << 5; i += 2) { + int word = i2c_smbus_read_word_data(client, i); + if (word < 0) goto exit; - data->data[i] = (u8) j; + data->data[i] = word & 0xff; + data->data[i + 1] = word >> 8; } } data->last_updated[slice] = jiffies; @@ -177,14 +174,15 @@ static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind) if (!(adapter->class & I2C_CLASS_SPD) && address >= 0x51) goto exit; - /* There are three ways we can read the EEPROM data: + /* There are four ways we can read the EEPROM data: (1) I2C block reads (faster, but unsupported by most adapters) - (2) Consecutive byte reads (100% overhead) - (3) Regular byte data reads (200% overhead) - The third method is not implemented by this driver because all - known adapters support at least the second. */ - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA - | I2C_FUNC_SMBUS_BYTE)) + (2) Word reads (128% overhead) + (3) Consecutive byte reads (88% overhead, unsafe) + (4) Regular byte data reads (265% overhead) + The third and fourth methods are not implemented by this driver + because all known adapters support one of the first two. */ + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA) + && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) goto exit; if (!(data = kzalloc(sizeof(struct eeprom_data), GFP_KERNEL))) { @@ -212,13 +210,14 @@ static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind) /* Detect the Vaio nature of EEPROMs. We use the "PCG-" or "VGN-" prefix as the signature. */ - if (address == 0x57) { + if (address == 0x57 + && i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) { char name[4]; name[0] = i2c_smbus_read_byte_data(new_client, 0x80); - name[1] = i2c_smbus_read_byte(new_client); - name[2] = i2c_smbus_read_byte(new_client); - name[3] = i2c_smbus_read_byte(new_client); + name[1] = i2c_smbus_read_byte_data(new_client, 0x81); + name[2] = i2c_smbus_read_byte_data(new_client, 0x82); + name[3] = i2c_smbus_read_byte_data(new_client, 0x83); if (!memcmp(name, "PCG-", 4) || !memcmp(name, "VGN-", 4)) { dev_info(&new_client->dev, "Vaio EEPROM detected, " |