Changeset 5935 for lm-sensors/trunk/prog/detect

Timestamp:

02/24/11 10:49:17 (15 months ago)

Author:

khali

Message:

Add detection of National Semiconductor LM75A.

Files:

• lm-sensors/trunk/prog/detect/sensors-detect (modified) (6 diffs)

lm-sensors/trunk/prog/detect/sensors-detect

@@ -503 +503 @@
                 i2c_detect => sub { lm75_detect(@_, 0); },
         }, {
+                name => "National Semiconductor LM75A",
+                driver => "lm75",
+                i2c_addrs => [0x48..0x4f],
+                i2c_detect => sub { lm75_detect(@_, 2); },
+        }, {
                 name => "Dallas Semiconductor DS75",
                 driver => "lm75",
@@ -3840 +3845 @@
 }
 
-# Chip to detect: 0 = LM75, 1 = DS75
+# Chip to detect: 0 = LM75, 1 = DS75, 2 = LM75A
 # Registers used:
 #   0x00: Temperature
@@ -3847 +3852 @@
 #   0x03: Overtemperature Shutdown
 #   0x04-0x07: No registers
+#   0x07: Device ID (LM75A only)
 # The first detection step is based on the fact that the LM75 has only
 # four registers, and cycles addresses over 8-byte boundaries. We use the
@@ -3856 +3862 @@
 # all register addresses from 0x04 to 0x0f behave like 0x04-0x07 do for
 # the LM75.
+# And the LM75A is again different, it cycles over 8-byte boundaries, but
+# registers 0x04-0x06 return 0xff. Thankfully it has a device ID register
+# at 0x07.
 # Not all devices enjoy SMBus read word transactions, so we use read byte
 # transactions even for the 16-bit registers. The low bits aren't very
@@ -3865 +3874 @@
         my $cur = i2c_smbus_read_byte_data($file, 0x00);
         my $conf = i2c_smbus_read_byte_data($file, 0x01);
-
-        my $hyst = i2c_smbus_read_byte_data($file, 0x02, NO_CACHE);
-        my $maxreg = $chip == 1 ? 0x0f : 0x07;
-        for $i (0x04 .. $maxreg) {
-                return if i2c_smbus_read_byte_data($file, $i, NO_CACHE) != $hyst;
-        }
-
-        my $os = i2c_smbus_read_byte_data($file, 0x03, NO_CACHE);
-        for $i (0x04 .. $maxreg) {
-                return if i2c_smbus_read_byte_data($file, $i, NO_CACHE) != $os;
-        }
-
-        if ($chip == 0) {
+        my ($maxreg, $hyst, $os, $dev_id);
+
+        if ($chip == 2) {       # LM75A
+                $dev_id = i2c_smbus_read_byte_data($file, 0x07);
+                return if $dev_id != 0xA1;
+
+                $hyst = i2c_smbus_read_byte_data($file, 0x02);
+                $os = i2c_smbus_read_byte_data($file, 0x03);
+
+                for $i (0x04 .. 0x06) {
+                        return if i2c_smbus_read_byte_data($file, $i) != 0xff;
+                }
+        } else {                # LM75 or DS75
+                $maxreg = $chip == 1 ? 0x0f : 0x07;
+                $hyst = i2c_smbus_read_byte_data($file, 0x02, NO_CACHE);
+                for $i (0x04 .. $maxreg) {
+                        return if i2c_smbus_read_byte_data($file, $i, NO_CACHE) != $hyst;
+                }
+
+                $os = i2c_smbus_read_byte_data($file, 0x03, NO_CACHE);
+                for $i (0x04 .. $maxreg) {
+                        return if i2c_smbus_read_byte_data($file, $i, NO_CACHE) != $os;
+                }
+        }
+
+        if ($chip != 1) {       # LM75 or LM75A
                 for ($i = 8; $i <= 248; $i += 40) {
                         return if i2c_smbus_read_byte_data($file, $i + 0x01) != $conf
                                or i2c_smbus_read_byte_data($file, $i + 0x02) != $hyst
                                or i2c_smbus_read_byte_data($file, $i + 0x03) != $os;
+                        return if $chip == 2
+                              and i2c_smbus_read_byte_data($file, $i + 0x07) != $dev_id;
                 }
         }
@@ -3889 +3913 @@
 
         # Unused bits
-        return if $chip == 0 and ($conf & 0xe0);
+        return if $chip != 1 and ($conf & 0xe0);
         return if $chip == 1 and ($conf & 0x80);