Handle errors on 8-bit register reads and writes too. Also use likely and unlikely to make the functions faster on success. Signed-off-by: Jean Delvare <khali@xxxxxxxxxxxx> Cc: Guenter Roeck <guenter.roeck@xxxxxxxxxxxx> --- drivers/hwmon/emc6w201.c | 58 ++++++++++++++++++++++++++++++++++------------ 1 file changed, 44 insertions(+), 14 deletions(-) --- linux-2.6.40-rc0.orig/drivers/hwmon/emc6w201.c 2011-05-27 09:46:54.000000000 +0200 +++ linux-2.6.40-rc0/drivers/hwmon/emc6w201.c 2011-05-27 13:36:21.000000000 +0200 @@ -78,8 +78,9 @@ static u16 emc6w201_read16(struct i2c_cl lsb = i2c_smbus_read_byte_data(client, reg); msb = i2c_smbus_read_byte_data(client, reg + 1); - if (lsb < 0 || msb < 0) { - dev_err(&client->dev, "16-bit read failed at 0x%02x\n", reg); + if (unlikely(lsb < 0 || msb < 0)) { + dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n", + 16, "read", reg); return 0xFFFF; /* Arbitrary value */ } @@ -95,10 +96,39 @@ static int emc6w201_write16(struct i2c_c int err; err = i2c_smbus_write_byte_data(client, reg, val & 0xff); - if (!err) + if (likely(!err)) err = i2c_smbus_write_byte_data(client, reg + 1, val >> 8); - if (err < 0) - dev_err(&client->dev, "16-bit write failed at 0x%02x\n", reg); + if (unlikely(err < 0)) + dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n", + 16, "write", reg); + + return err; +} + +/* Read 8-bit value from register */ +static u8 emc6w201_read8(struct i2c_client *client, u8 reg) +{ + int val; + + val = i2c_smbus_read_byte_data(client, reg); + if (unlikely(val < 0)) { + dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n", + 8, "read", reg); + return 0x00; /* Arbitrary value */ + } + + return val; +} + +/* Write 8-bit value to register */ +static int emc6w201_write8(struct i2c_client *client, u8 reg, u8 val) +{ + int err; + + err = i2c_smbus_write_byte_data(client, reg, val); + if (unlikely(err < 0)) + dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n", + 8, "write", reg); return err; } @@ -114,25 +144,25 @@ static struct emc6w201_data *emc6w201_up if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { for (nr = 0; nr < 6; nr++) { data->in[input][nr] = - i2c_smbus_read_byte_data(client, + emc6w201_read8(client, EMC6W201_REG_IN(nr)); data->in[min][nr] = - i2c_smbus_read_byte_data(client, + emc6w201_read8(client, EMC6W201_REG_IN_LOW(nr)); data->in[max][nr] = - i2c_smbus_read_byte_data(client, + emc6w201_read8(client, EMC6W201_REG_IN_HIGH(nr)); } for (nr = 0; nr < 6; nr++) { data->temp[input][nr] = - i2c_smbus_read_byte_data(client, + emc6w201_read8(client, EMC6W201_REG_TEMP(nr)); data->temp[min][nr] = - i2c_smbus_read_byte_data(client, + emc6w201_read8(client, EMC6W201_REG_TEMP_LOW(nr)); data->temp[max][nr] = - i2c_smbus_read_byte_data(client, + emc6w201_read8(client, EMC6W201_REG_TEMP_HIGH(nr)); } @@ -192,7 +222,7 @@ static ssize_t set_in(struct device *dev mutex_lock(&data->update_lock); data->in[sf][nr] = SENSORS_LIMIT(val, 0, 255); - err = i2c_smbus_write_byte_data(client, reg, data->in[sf][nr]); + err = emc6w201_write8(client, reg, data->in[sf][nr]); mutex_unlock(&data->update_lock); return err < 0 ? err : count; @@ -229,7 +259,7 @@ static ssize_t set_temp(struct device *d mutex_lock(&data->update_lock); data->temp[sf][nr] = SENSORS_LIMIT(val, -127, 128); - err = i2c_smbus_write_byte_data(client, reg, data->temp[sf][nr]); + err = emc6w201_write8(client, reg, data->temp[sf][nr]); mutex_unlock(&data->update_lock); return err < 0 ? err : count; @@ -444,7 +474,7 @@ static int emc6w201_detect(struct i2c_cl /* Check configuration */ config = i2c_smbus_read_byte_data(client, EMC6W201_REG_CONFIG); - if ((config & 0xF4) != 0x04) + if (config < 0 || (config & 0xF4) != 0x04) return -ENODEV; if (!(config & 0x01)) { dev_err(&client->dev, "Monitoring not enabled\n"); -- Jean Delvare _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors