X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fi2c%2Fchips%2Flm75.c;h=3752a2706194fce09ae7b205d4471fd8607f7dd5;hb=9bf4aaab3e101692164d49b7ca357651eb691cb6;hp=5c6ebdc096eaccbd6ed30a3a5e9a322492d27727;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/drivers/i2c/chips/lm75.c b/drivers/i2c/chips/lm75.c
index 5c6ebdc09..3752a2706 100644
--- a/drivers/i2c/chips/lm75.c
+++ b/drivers/i2c/chips/lm75.c
@@ -105,7 +105,7 @@ static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL);
 
 static int lm75_attach_adapter(struct i2c_adapter *adapter)
 {
-	if (!(adapter->class & I2C_ADAP_CLASS_SMBUS))
+	if (!(adapter->class & I2C_CLASS_HWMON))
 		return 0;
 	return i2c_detect(adapter, &addr_data, lm75_detect);
 }
@@ -113,7 +113,7 @@ static int lm75_attach_adapter(struct i2c_adapter *adapter)
 /* This function is called by i2c_detect */
 static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
 {
-	int i, cur, conf, hyst, os;
+	int i;
 	struct i2c_client *new_client;
 	struct lm75_data *data;
 	int err = 0;
@@ -149,16 +149,41 @@ static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
 	new_client->driver = &lm75_driver;
 	new_client->flags = 0;
 
-	/* Now, we do the remaining detection. It is lousy. */
+	/* Now, we do the remaining detection. There is no identification-
+	   dedicated register so we have to rely on several tricks:
+	   unused bits, registers cycling over 8-address boundaries,
+	   addresses 0x04-0x07 returning the last read value.
+	   The cycling+unused addresses combination is not tested,
+	   since it would significantly slow the detection down and would
+	   hardly add any value. */
 	if (kind < 0) {
+		int cur, conf, hyst, os;
+
+		/* Unused addresses */
 		cur = i2c_smbus_read_word_data(new_client, 0);
 		conf = i2c_smbus_read_byte_data(new_client, 1);
 		hyst = i2c_smbus_read_word_data(new_client, 2);
+		if (i2c_smbus_read_word_data(new_client, 4) != hyst
+		 || i2c_smbus_read_word_data(new_client, 5) != hyst
+		 || i2c_smbus_read_word_data(new_client, 6) != hyst
+		 || i2c_smbus_read_word_data(new_client, 7) != hyst)
+		 	goto exit_free;
 		os = i2c_smbus_read_word_data(new_client, 3);
-		for (i = 0; i <= 0x1f; i++)
-			if ((i2c_smbus_read_byte_data(new_client, i * 8 + 1) != conf) ||
-			    (i2c_smbus_read_word_data(new_client, i * 8 + 2) != hyst) ||
-			    (i2c_smbus_read_word_data(new_client, i * 8 + 3) != os))
+		if (i2c_smbus_read_word_data(new_client, 4) != os
+		 || i2c_smbus_read_word_data(new_client, 5) != os
+		 || i2c_smbus_read_word_data(new_client, 6) != os
+		 || i2c_smbus_read_word_data(new_client, 7) != os)
+		 	goto exit_free;
+
+		/* Unused bits */
+		if (conf & 0xe0)
+		 	goto exit_free;
+
+		/* Addresses cycling */
+		for (i = 8; i < 0xff; i += 8)
+			if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
+			 || i2c_smbus_read_word_data(new_client, i + 2) != hyst
+			 || i2c_smbus_read_word_data(new_client, i + 3) != os)
 				goto exit_free;
 	}