sensors-detect: Nuvoton chip updates

Document driver support for NCT7802Y.
Add detection of NCT7904D.

CHANGES

@@ -33,6 +33,8 @@ SVN HEAD
                   Add detection of Intel 5500/5520/X58
                   Loosen detection rules for TS3000/TSE2002
                   Add detection of TSE2004 and TS3001
+                  Document driver support for NCT7802Y
+                  Add detection of NCT7904D
 
 3.3.5 "Happy Birthday Beddy" (2014-01-22)
   libsensors: Improve documentation of two functions

prog/detect/sensors-detect

@@ -734,9 +734,14 @@ use vars qw(@i2c_adapter_names);
 		i2c_detect => sub { w83795_detect(@_); },
 	}, {
 		name => "Nuvoton NCT7802Y",
-		driver => "to-be-written",
+		driver => "nct7802",
 		i2c_addrs => [0x28..0x2f],
 		i2c_detect => sub { nct7802_detect(@_); },
+	}, {
+		name => "Nuvoton NCT7904D",
+		driver => "nct7904",
+		i2c_addrs => [0x2d..0x2e],
+		i2c_detect => sub { nct7904_detect(@_); },
 	}, {
 		name => "Winbond W83627HF",
 		driver => "use-isa-instead",
@@ -5634,6 +5639,32 @@ sub nct7802_detect
 	return 8;
 }
 
+# Registers used:
+#   0x7a: Vendor ID
+#   0x7b: Chip ID
+#   0x7c: Device ID
+#   0xff: Bank Select
+#
+sub nct7904_detect
+{
+	my ($reg);
+	my ($file, $addr) = @_;
+
+	$reg = i2c_smbus_read_byte_data($file, 0x7a);
+	return unless $reg == 0x50;
+
+	$reg = i2c_smbus_read_byte_data($file, 0x7b);
+	return unless $reg == 0xc5;
+
+	$reg = i2c_smbus_read_byte_data($file, 0x7c);
+	return unless ($reg & 0xf0) == 0x50;
+
+	$reg = i2c_smbus_read_byte_data($file, 0xff);
+	return unless ($reg & 0xf8) == 0x00;
+
+	return 8;
+}
+
 # Registers used:
 #   0x48: Full I2C Address
 #   0x4e: Vendor ID byte selection