hwmon: (lm80) Add detection of NatSemi/TI LM96080

Add detection of the National Semiconductor (now Texas Instruments)
LM96080. It is functionally compatible with the LM80 but detection is
completely different.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>

diff --git a/Documentation/hwmon/lm80 b/Documentation/hwmon/lm80
index cb5b407..a60b43e 100644 (file)
--- a/Documentation/hwmon/lm80
+++ b/Documentation/hwmon/lm80
@@ -7,6 +7,11 @@ Supported chips:
     Addresses scanned: I2C 0x28 - 0x2f
     Datasheet: Publicly available at the National Semiconductor website
                http://www.national.com/
+  * National Semiconductor LM96080
+    Prefix: 'lm96080'
+    Addresses scanned: I2C 0x28 - 0x2f
+    Datasheet: Publicly available at the National Semiconductor website
+               http://www.national.com/
 
 Authors:
         Frodo Looijaard <frodol@dds.nl>,
@@ -17,7 +22,9 @@ Description
 
 This driver implements support for the National Semiconductor LM80.
 It is described as a 'Serial Interface ACPI-Compatible Microprocessor
-System Hardware Monitor'.
+System Hardware Monitor'. The LM96080 is a more recent incarnation,
+it is pin and register compatible, with a few additional features not
+yet supported by the driver.
 
 The LM80 implements one temperature sensor, two fan rotation speed sensors,
 seven voltage sensors, alarms, and some miscellaneous stuff.

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index dad895f..1cd0e20 100644 (file)
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -598,11 +598,11 @@ config SENSORS_LM78
          will be called lm78.
 
 config SENSORS_LM80
-       tristate "National Semiconductor LM80"
+       tristate "National Semiconductor LM80 and LM96080"
        depends on I2C
        help
          If you say yes here you get support for National Semiconductor
-         LM80 sensor chips.
+         LM80 and LM96080 sensor chips.
 
          This driver can also be built as a module.  If so, the module
          will be called lm80.

diff --git a/drivers/hwmon/lm80.c b/drivers/hwmon/lm80.c
index a996f27..e2c43e1 100644 (file)
--- a/drivers/hwmon/lm80.c
+++ b/drivers/hwmon/lm80.c
@@ -60,6 +60,10 @@ static const unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
 #define LM80_REG_FANDIV                        0x05
 #define LM80_REG_RES                   0x06
 
+#define LM96080_REG_CONV_RATE          0x07
+#define LM96080_REG_MAN_ID             0x3e
+#define LM96080_REG_DEV_ID             0x3f
+
 
 /*
  * Conversions. Rounding and limit checking is only done on the TO_REG
@@ -147,6 +151,7 @@ static int lm80_write_value(struct i2c_client *client, u8 reg, u8 value);
 
 static const struct i2c_device_id lm80_id[] = {
        { "lm80", 0 },
+       { "lm96080", 1 },
        { }
 };
 MODULE_DEVICE_TABLE(i2c, lm80_id);
@@ -490,23 +495,44 @@ static const struct attribute_group lm80_group = {
 static int lm80_detect(struct i2c_client *client, struct i2c_board_info *info)
 {
        struct i2c_adapter *adapter = client->adapter;
-       int i, cur;
+       int i, cur, man_id, dev_id;
+       const char *name = NULL;
 
        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
                return -ENODEV;
 
-       /* Now, we do the remaining detection. It is lousy. */
-       if (lm80_read_value(client, LM80_REG_ALARM2) & 0xc0)
+       /* First check for unused bits, common to both chip types */
+       if ((lm80_read_value(client, LM80_REG_ALARM2) & 0xc0)
+        || (lm80_read_value(client, LM80_REG_CONFIG) & 0x80))
                return -ENODEV;
-       for (i = 0x2a; i <= 0x3d; i++) {
-               cur = i2c_smbus_read_byte_data(client, i);
-               if ((i2c_smbus_read_byte_data(client, i + 0x40) != cur)
-                || (i2c_smbus_read_byte_data(client, i + 0x80) != cur)
-                || (i2c_smbus_read_byte_data(client, i + 0xc0) != cur))
+
+       /*
+        * The LM96080 has manufacturer and stepping/die rev registers so we
+        * can just check that. The LM80 does not have such registers so we
+        * have to use a more expensive trick.
+        */
+       man_id = lm80_read_value(client, LM96080_REG_MAN_ID);
+       dev_id = lm80_read_value(client, LM96080_REG_DEV_ID);
+       if (man_id == 0x01 && dev_id == 0x08) {
+               /* Check more unused bits for confirmation */
+               if (lm80_read_value(client, LM96080_REG_CONV_RATE) & 0xfe)
                        return -ENODEV;
+
+               name = "lm96080";
+       } else {
+               /* Check 6-bit addressing */
+               for (i = 0x2a; i <= 0x3d; i++) {
+                       cur = i2c_smbus_read_byte_data(client, i);
+                       if ((i2c_smbus_read_byte_data(client, i + 0x40) != cur)
+                        || (i2c_smbus_read_byte_data(client, i + 0x80) != cur)
+                        || (i2c_smbus_read_byte_data(client, i + 0xc0) != cur))
+                               return -ENODEV;
+               }
+
+               name = "lm80";
        }
 
-       strlcpy(info->type, "lm80", I2C_NAME_SIZE);
+       strlcpy(info->type, name, I2C_NAME_SIZE);
 
        return 0;
 }