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path: root/drivers/hwmon/lm73.c
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Diffstat (limited to 'drivers/hwmon/lm73.c')
-rw-r--r--drivers/hwmon/lm73.c30
1 files changed, 22 insertions, 8 deletions
diff --git a/drivers/hwmon/lm73.c b/drivers/hwmon/lm73.c
index 29b9030d42c3..9e64d96620d3 100644
--- a/drivers/hwmon/lm73.c
+++ b/drivers/hwmon/lm73.c
@@ -34,7 +34,7 @@ static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c,
#define LM73_REG_CTRL 0x04
#define LM73_REG_ID 0x07
-#define LM73_ID 0x9001 /* or 0x190 after a swab16() */
+#define LM73_ID 0x9001 /* 0x0190, byte-swapped */
#define DRVNAME "lm73"
#define LM73_TEMP_MIN (-40)
#define LM73_TEMP_MAX 150
@@ -57,7 +57,7 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *da,
/* Write value */
value = (short) SENSORS_LIMIT(temp/250, (LM73_TEMP_MIN*4),
(LM73_TEMP_MAX*4)) << 5;
- i2c_smbus_write_word_data(client, attr->index, swab16(value));
+ i2c_smbus_write_word_swapped(client, attr->index, value);
return count;
}
@@ -68,8 +68,8 @@ static ssize_t show_temp(struct device *dev, struct device_attribute *da,
struct i2c_client *client = to_i2c_client(dev);
/* use integer division instead of equivalent right shift to
guarantee arithmetic shift and preserve the sign */
- int temp = ((s16) (swab16(i2c_smbus_read_word_data(client,
- attr->index)))*250) / 32;
+ int temp = ((s16) (i2c_smbus_read_word_swapped(client,
+ attr->index))*250) / 32;
return sprintf(buf, "%d\n", temp);
}
@@ -150,17 +150,31 @@ static int lm73_detect(struct i2c_client *new_client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
- u16 id;
- u8 ctrl;
+ int id, ctrl, conf;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
+ /*
+ * Do as much detection as possible with byte reads first, as word
+ * reads can confuse other devices.
+ */
+ ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL);
+ if (ctrl < 0 || (ctrl & 0x10))
+ return -ENODEV;
+
+ conf = i2c_smbus_read_byte_data(new_client, LM73_REG_CONF);
+ if (conf < 0 || (conf & 0x0c))
+ return -ENODEV;
+
+ id = i2c_smbus_read_byte_data(new_client, LM73_REG_ID);
+ if (id < 0 || id != (LM73_ID & 0xff))
+ return -ENODEV;
+
/* Check device ID */
id = i2c_smbus_read_word_data(new_client, LM73_REG_ID);
- ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL);
- if ((id != LM73_ID) || (ctrl & 0x10))
+ if (id < 0 || id != LM73_ID)
return -ENODEV;
strlcpy(info->type, "lm73", I2C_NAME_SIZE);