hwmon: (dme1737) Add SCH5127 support

Add support for the hardware monitoring capabilities of the SCH5127
chip to the dme1737 driver.
Signed-off-by: Juerg Haefliger <juergh@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Jeff Rickman <jrickman@myamigos.us>

Documentation/hwmon/dme1737

@@ -9,11 +9,15 @@ Supported chips:
   * SMSC SCH3112, SCH3114, SCH3116
     Prefix: 'sch311x'
     Addresses scanned: none, address read from Super-I/O config space
-    Datasheet: http://www.nuhorizons.com/FeaturedProducts/Volume1/SMSC/311x.pdf
+    Datasheet: Available on the Internet
   * SMSC SCH5027
     Prefix: 'sch5027'
     Addresses scanned: I2C 0x2c, 0x2d, 0x2e
     Datasheet: Provided by SMSC upon request and under NDA
+  * SMSC SCH5127
+    Prefix: 'sch5127'
+    Addresses scanned: none, address read from Super-I/O config space
+    Datasheet: Provided by SMSC upon request and under NDA
 
 Authors:
     Juerg Haefliger <juergh@gmail.com>
@@ -36,8 +40,8 @@ Description
 -----------
 
 This driver implements support for the hardware monitoring capabilities of the
-SMSC DME1737 and Asus A8000 (which are the same), SMSC SCH5027, and SMSC
-SCH311x Super-I/O chips. These chips feature monitoring of 3 temp sensors
+SMSC DME1737 and Asus A8000 (which are the same), SMSC SCH5027, SCH311x,
+and SCH5127 Super-I/O chips. These chips feature monitoring of 3 temp sensors
 temp[1-3] (2 remote diodes and 1 internal), 7 voltages in[0-6] (6 external and
 1 internal) and up to 6 fan speeds fan[1-6]. Additionally, the chips implement
 up to 5 PWM outputs pwm[1-3,5-6] for controlling fan speeds both manually and
@@ -48,14 +52,14 @@ Fan[3-6] and pwm[3,5-6] are optional features and their availability depends on
 the configuration of the chip. The driver will detect which features are
 present during initialization and create the sysfs attributes accordingly.
 
-For the SCH311x, fan[1-3] and pwm[1-3] are always present and fan[4-6] and
-pwm[5-6] don't exist.
+For the SCH311x and SCH5127, fan[1-3] and pwm[1-3] are always present and
+fan[4-6] and pwm[5-6] don't exist.
 
 The hardware monitoring features of the DME1737, A8000, and SCH5027 are only
-accessible via SMBus, while the SCH311x only provides access via the ISA bus.
-The driver will therefore register itself as an I2C client driver if it detects
-a DME1737, A8000, or SCH5027 and as a platform driver if it detects a SCH311x
-chip.
+accessible via SMBus, while the SCH311x and SCH5127 only provide access via
+the ISA bus. The driver will therefore register itself as an I2C client driver
+if it detects a DME1737, A8000, or SCH5027 and as a platform driver if it
+detects a SCH311x or SCH5127 chip.
 
 
 Voltage Monitoring
@@ -76,7 +80,7 @@ DME1737, A8000:
 	in6: Vbat	(+3.0V)			0V - 4.38V
 
 SCH311x:
-	in0: +2.5V				0V - 6.64V
+	in0: +2.5V				0V - 3.32V
 	in1: Vccp	(processor core)	0V - 2V
 	in2: VCC	(internal +3.3V)	0V - 4.38V
 	in3: +5V				0V - 6.64V
@@ -93,6 +97,15 @@ SCH5027:
 	in5: VTR	(+3.3V standby)		0V - 4.38V
 	in6: Vbat	(+3.0V)			0V - 4.38V
 
+SCH5127:
+	in0: +2.5				0V - 3.32V
+	in1: Vccp	(processor core)	0V - 3V
+	in2: VCC	(internal +3.3V)	0V - 4.38V
+	in3: V2_IN				0V - 1.5V
+	in4: V1_IN				0V - 1.5V
+	in5: VTR	(+3.3V standby)		0V - 4.38V
+	in6: Vbat	(+3.0V)			0V - 4.38V
+
 Each voltage input has associated min and max limits which trigger an alarm
 when crossed.
 
@@ -293,3 +306,21 @@ pwm[1-3]_auto_point1_pwm	RW	Auto PWM pwm point. Auto_point1 is the
 pwm[1-3]_auto_point2_pwm	RO	Auto PWM pwm point. Auto_point2 is the
 					full-speed duty-cycle which is hard-
 					wired to 255 (100% duty-cycle).
+
+Chip Differences
+----------------
+
+Feature			dme1737	sch311x	sch5027	sch5127
+-------------------------------------------------------
+temp[1-3]_offset	yes	yes
+vid			yes
+zone3			yes	yes	yes
+zone[1-3]_hyst		yes	yes
+pwm min/off		yes	yes
+fan3			opt	yes	opt	yes
+pwm3			opt	yes	opt	yes
+fan4			opt		opt
+fan5			opt		opt
+pwm5			opt		opt
+fan6			opt		opt
+pwm6			opt		opt

drivers/hwmon/dme1737.c

 /*
- * dme1737.c - Driver for the SMSC DME1737, Asus A8000, SMSC SCH311x and
- *             SCH5027 Super-I/O chips integrated hardware monitoring features.
- * Copyright (c) 2007, 2008 Juerg Haefliger <juergh@gmail.com>
+ * dme1737.c - Driver for the SMSC DME1737, Asus A8000, SMSC SCH311x, SCH5027,
+ *             and SCH5127 Super-I/O chips integrated hardware monitoring
+ *             features.
+ * Copyright (c) 2007, 2008, 2009, 2010 Juerg Haefliger <juergh@gmail.com>
  *
  * This driver is an I2C/ISA hybrid, meaning that it uses the I2C bus to access
  * the chip registers if a DME1737, A8000, or SCH5027 is found and the ISA bus
- * if a SCH311x chip is found. Both types of chips have very similar hardware
- * monitoring capabilities but differ in the way they can be accessed.
+ * if a SCH311x or SCH5127 chip is found. Both types of chips have very
+ * similar hardware monitoring capabilities but differ in the way they can be
+ * accessed.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -57,7 +59,7 @@ MODULE_PARM_DESC(probe_all_addr, "Include probing of non-standard LPC "
 /* Addresses to scan */
 static const unsigned short normal_i2c[] = {0x2c, 0x2d, 0x2e, I2C_CLIENT_END};
 
-enum chips { dme1737, sch5027, sch311x };
+enum chips { dme1737, sch5027, sch311x, sch5127 };
 
 /* ---------------------------------------------------------------------
  * Registers
@@ -164,10 +166,29 @@ static const u8 DME1737_BIT_ALARM_FAN[] = {10, 11, 12, 13, 22, 23};
 #define DME1737_VERSTEP_MASK	0xf8
 #define SCH311X_DEVICE		0x8c
 #define SCH5027_VERSTEP		0x69
+#define SCH5127_DEVICE		0x8e
+
+/* Device ID values (global configuration register index 0x20) */
+#define DME1737_ID_1	0x77
+#define DME1737_ID_2	0x78
+#define SCH3112_ID	0x7c
+#define SCH3114_ID	0x7d
+#define SCH3116_ID	0x7f
+#define SCH5027_ID	0x89
+#define SCH5127_ID	0x86
 
 /* Length of ISA address segment */
 #define DME1737_EXTENT	2
 
+/* chip-dependent features */
+#define HAS_TEMP_OFFSET		(1 << 0)		/* bit 0 */
+#define HAS_VID			(1 << 1)		/* bit 1 */
+#define HAS_ZONE3		(1 << 2)		/* bit 2 */
+#define HAS_ZONE_HYST		(1 << 3)		/* bit 3 */
+#define HAS_PWM_MIN		(1 << 4)		/* bit 4 */
+#define HAS_FAN(ix)		(1 << ((ix) + 5))	/* bits 5-10 */
+#define HAS_PWM(ix)		(1 << ((ix) + 11))	/* bits 11-16 */
+
 /* ---------------------------------------------------------------------
  * Data structures and manipulation thereof
  * --------------------------------------------------------------------- */
@@ -187,8 +208,7 @@ struct dme1737_data {
 
 	u8 vid;
 	u8 pwm_rr_en;
-	u8 has_pwm;
-	u8 has_fan;
+	u32 has_features;
 
 	/* Register values */
 	u16 in[7];
@@ -224,8 +244,11 @@ static const int IN_NOMINAL_SCH311x[] = {2500, 1500, 3300, 5000, 12000, 3300,
 					 3300};
 static const int IN_NOMINAL_SCH5027[] = {5000, 2250, 3300, 1125, 1125, 3300,
 					 3300};
+static const int IN_NOMINAL_SCH5127[] = {2500, 2250, 3300, 1125, 1125, 3300,
+					 3300};
 #define IN_NOMINAL(type)	((type) == sch311x ? IN_NOMINAL_SCH311x : \
 				 (type) == sch5027 ? IN_NOMINAL_SCH5027 : \
+				 (type) == sch5127 ? IN_NOMINAL_SCH5127 : \
 				 IN_NOMINAL_DME1737)
 
 /* Voltage input
@@ -568,7 +591,7 @@ static struct dme1737_data *dme1737_update_device(struct device *dev)
 
 	/* Sample register contents every 1 sec */
 	if (time_after(jiffies, data->last_update + HZ) || !data->valid) {
-		if (data->type == dme1737) {
+		if (data->has_features & HAS_VID) {
 			data->vid = dme1737_read(data, DME1737_REG_VID) &
 				0x3f;
 		}
@@ -599,7 +622,7 @@ static struct dme1737_data *dme1737_update_device(struct device *dev)
 					DME1737_REG_TEMP_MIN(ix));
 			data->temp_max[ix] = dme1737_read(data,
 					DME1737_REG_TEMP_MAX(ix));
-			if (data->type != sch5027) {
+			if (data->has_features & HAS_TEMP_OFFSET) {
 				data->temp_offset[ix] = dme1737_read(data,
 						DME1737_REG_TEMP_OFFSET(ix));
 			}
@@ -626,7 +649,7 @@ static struct dme1737_data *dme1737_update_device(struct device *dev)
 		for (ix = 0; ix < ARRAY_SIZE(data->fan); ix++) {
 			/* Skip reading registers if optional fans are not
 			 * present */
-			if (!(data->has_fan & (1 << ix))) {
+			if (!(data->has_features & HAS_FAN(ix))) {
 				continue;
 			}
 			data->fan[ix] = dme1737_read(data,
@@ -650,7 +673,7 @@ static struct dme1737_data *dme1737_update_device(struct device *dev)
 		for (ix = 0; ix < ARRAY_SIZE(data->pwm); ix++) {
 			/* Skip reading registers if optional PWMs are not
 			 * present */
-			if (!(data->has_pwm & (1 << ix))) {
+			if (!(data->has_features & HAS_PWM(ix))) {
 				continue;
 			}
 			data->pwm[ix] = dme1737_read(data,
@@ -672,12 +695,24 @@ static struct dme1737_data *dme1737_update_device(struct device *dev)
 
 		/* Thermal zone registers */
 		for (ix = 0; ix < ARRAY_SIZE(data->zone_low); ix++) {
-			data->zone_low[ix] = dme1737_read(data,
-					DME1737_REG_ZONE_LOW(ix));
-			data->zone_abs[ix] = dme1737_read(data,
-					DME1737_REG_ZONE_ABS(ix));
+			/* Skip reading registers if zone3 is not present */
+			if ((ix == 2) && !(data->has_features & HAS_ZONE3)) {
+				continue;
+			}
+			/* sch5127 zone2 registers are special */
+			if ((ix == 1) && (data->type == sch5127)) {
+				data->zone_low[1] = dme1737_read(data,
+						DME1737_REG_ZONE_LOW(2));
+				data->zone_abs[1] = dme1737_read(data,
+						DME1737_REG_ZONE_ABS(2));
+			} else {
+				data->zone_low[ix] = dme1737_read(data,
+						DME1737_REG_ZONE_LOW(ix));
+				data->zone_abs[ix] = dme1737_read(data,
+						DME1737_REG_ZONE_ABS(ix));
+			}
 		}
-		if (data->type != sch5027) {
+		if (data->has_features & HAS_ZONE_HYST) {
 			for (ix = 0; ix < ARRAY_SIZE(data->zone_hyst); ix++) {
 				data->zone_hyst[ix] = dme1737_read(data,
 						DME1737_REG_ZONE_HYST(ix));
@@ -1594,10 +1629,6 @@ static struct attribute *dme1737_attr[] ={
 	&sensor_dev_attr_zone2_auto_point2_temp.dev_attr.attr,
 	&sensor_dev_attr_zone2_auto_point3_temp.dev_attr.attr,
 	&sensor_dev_attr_zone2_auto_channels_temp.dev_attr.attr,
-	&sensor_dev_attr_zone3_auto_point1_temp.dev_attr.attr,
-	&sensor_dev_attr_zone3_auto_point2_temp.dev_attr.attr,
-	&sensor_dev_attr_zone3_auto_point3_temp.dev_attr.attr,
-	&sensor_dev_attr_zone3_auto_channels_temp.dev_attr.attr,
 	NULL
 };
 
@@ -1605,27 +1636,23 @@ static const struct attribute_group dme1737_group = {
 	.attrs = dme1737_attr,
 };
 
-/* The following struct holds misc attributes, which are not available in all
- * chips. Their creation depends on the chip type which is determined during
- * module load. */
-static struct attribute *dme1737_misc_attr[] = {
-	/* Temperatures */
+/* The following struct holds temp offset attributes, which are not available
+ * in all chips. The following chips support them:
+ * DME1737, SCH311x */
+static struct attribute *dme1737_temp_offset_attr[] = {
 	&sensor_dev_attr_temp1_offset.dev_attr.attr,
 	&sensor_dev_attr_temp2_offset.dev_attr.attr,
 	&sensor_dev_attr_temp3_offset.dev_attr.attr,
-	/* Zones */
-	&sensor_dev_attr_zone1_auto_point1_temp_hyst.dev_attr.attr,
-	&sensor_dev_attr_zone2_auto_point1_temp_hyst.dev_attr.attr,
-	&sensor_dev_attr_zone3_auto_point1_temp_hyst.dev_attr.attr,
 	NULL
 };
 
-static const struct attribute_group dme1737_misc_group = {
-	.attrs = dme1737_misc_attr,
+static const struct attribute_group dme1737_temp_offset_group = {
+	.attrs = dme1737_temp_offset_attr,
 };
 
-/* The following struct holds VID-related attributes. Their creation
-   depends on the chip type which is determined during module load. */
+/* The following struct holds VID related attributes, which are not available
+ * in all chips. The following chips support them:
+ * DME1737 */
 static struct attribute *dme1737_vid_attr[] = {
 	&dev_attr_vrm.attr,
 	&dev_attr_cpu0_vid.attr,
@@ -1636,6 +1663,36 @@ static const struct attribute_group dme1737_vid_group = {
 	.attrs = dme1737_vid_attr,
 };
 
+/* The following struct holds temp zone 3 related attributes, which are not
+ * available in all chips. The following chips support them:
+ * DME1737, SCH311x, SCH5027 */
+static struct attribute *dme1737_zone3_attr[] = {
+	&sensor_dev_attr_zone3_auto_point1_temp.dev_attr.attr,
+	&sensor_dev_attr_zone3_auto_point2_temp.dev_attr.attr,
+	&sensor_dev_attr_zone3_auto_point3_temp.dev_attr.attr,
+	&sensor_dev_attr_zone3_auto_channels_temp.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group dme1737_zone3_group = {
+	.attrs = dme1737_zone3_attr,
+};
+
+
+/* The following struct holds temp zone hysteresis  related attributes, which
+ * are not available in all chips. The following chips support them:
+ * DME1737, SCH311x */
+static struct attribute *dme1737_zone_hyst_attr[] = {
+	&sensor_dev_attr_zone1_auto_point1_temp_hyst.dev_attr.attr,
+	&sensor_dev_attr_zone2_auto_point1_temp_hyst.dev_attr.attr,
+	&sensor_dev_attr_zone3_auto_point1_temp_hyst.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group dme1737_zone_hyst_group = {
+	.attrs = dme1737_zone_hyst_attr,
+};
+
 /* The following structs hold the PWM attributes, some of which are optional.
  * Their creation depends on the chip configuration which is determined during
  * module load. */
@@ -1691,10 +1748,10 @@ static const struct attribute_group dme1737_pwm_group[] = {
 	{ .attrs = dme1737_pwm6_attr },
 };
 
-/* The following struct holds misc PWM attributes, which are not available in
- * all chips. Their creation depends on the chip type which is determined
+/* The following struct holds auto PWM min attributes, which are not available
+ * in all chips. Their creation depends on the chip type which is determined
  * during module load. */
-static struct attribute *dme1737_pwm_misc_attr[] = {
+static struct attribute *dme1737_auto_pwm_min_attr[] = {
 	&sensor_dev_attr_pwm1_auto_pwm_min.dev_attr.attr,
 	&sensor_dev_attr_pwm2_auto_pwm_min.dev_attr.attr,
 	&sensor_dev_attr_pwm3_auto_pwm_min.dev_attr.attr,
@@ -1764,14 +1821,25 @@ static struct attribute *dme1737_zone_chmod_attr[] = {
 	&sensor_dev_attr_zone2_auto_point1_temp.dev_attr.attr,
 	&sensor_dev_attr_zone2_auto_point2_temp.dev_attr.attr,
 	&sensor_dev_attr_zone2_auto_point3_temp.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group dme1737_zone_chmod_group = {
+	.attrs = dme1737_zone_chmod_attr,
+};
+
+
+/* The permissions of the following zone 3 attributes are changed to read-
+ * writeable if the chip is *not* locked. Otherwise they stay read-only. */
+static struct attribute *dme1737_zone3_chmod_attr[] = {
 	&sensor_dev_attr_zone3_auto_point1_temp.dev_attr.attr,
 	&sensor_dev_attr_zone3_auto_point2_temp.dev_attr.attr,
 	&sensor_dev_attr_zone3_auto_point3_temp.dev_attr.attr,
 	NULL
 };
 
-static const struct attribute_group dme1737_zone_chmod_group = {
-	.attrs = dme1737_zone_chmod_attr,
+static const struct attribute_group dme1737_zone3_chmod_group = {
+	.attrs = dme1737_zone3_chmod_attr,
 };
 
 /* The permissions of the following PWM attributes are changed to read-
@@ -1887,30 +1955,35 @@ static void dme1737_remove_files(struct device *dev)
 	int ix;
 
 	for (ix = 0; ix < ARRAY_SIZE(dme1737_fan_group); ix++) {
-		if (data->has_fan & (1 << ix)) {
+		if (data->has_features & HAS_FAN(ix)) {
 			sysfs_remove_group(&dev->kobj,
 					   &dme1737_fan_group[ix]);
 		}
 	}
 
 	for (ix = 0; ix < ARRAY_SIZE(dme1737_pwm_group); ix++) {
-		if (data->has_pwm & (1 << ix)) {
+		if (data->has_features & HAS_PWM(ix)) {
 			sysfs_remove_group(&dev->kobj,
 					   &dme1737_pwm_group[ix]);
-			if (data->type != sch5027 && ix < 3) {
+			if ((data->has_features & HAS_PWM_MIN) && ix < 3) {
 				sysfs_remove_file(&dev->kobj,
-						  dme1737_pwm_misc_attr[ix]);
+						dme1737_auto_pwm_min_attr[ix]);
 			}
 		}
 	}
 
-	if (data->type != sch5027) {
-		sysfs_remove_group(&dev->kobj, &dme1737_misc_group);
+	if (data->has_features & HAS_TEMP_OFFSET) {
+		sysfs_remove_group(&dev->kobj, &dme1737_temp_offset_group);
 	}
-	if (data->type == dme1737) {
+	if (data->has_features & HAS_VID) {
 		sysfs_remove_group(&dev->kobj, &dme1737_vid_group);
 	}
-
+	if (data->has_features & HAS_ZONE3) {
+		sysfs_remove_group(&dev->kobj, &dme1737_zone3_group);
+	}
+	if (data->has_features & HAS_ZONE_HYST) {
+		sysfs_remove_group(&dev->kobj, &dme1737_zone_hyst_group);
+	}
 	sysfs_remove_group(&dev->kobj, &dme1737_group);
 
 	if (!data->client) {
@@ -1934,23 +2007,31 @@ static int dme1737_create_files(struct device *dev)
 		goto exit_remove;
 	}
 
-	/* Create misc sysfs attributes */
-	if ((data->type != sch5027) &&
+	/* Create chip-dependent sysfs attributes */
+	if ((data->has_features & HAS_TEMP_OFFSET) &&
 	    (err = sysfs_create_group(&dev->kobj,
-				      &dme1737_misc_group))) {
+				      &dme1737_temp_offset_group))) {
 		goto exit_remove;
 	}
-
-	/* Create VID-related sysfs attributes */
-	if ((data->type == dme1737) &&
+	if ((data->has_features & HAS_VID) &&
 	    (err = sysfs_create_group(&dev->kobj,
 				      &dme1737_vid_group))) {
 		goto exit_remove;
 	}
+	if ((data->has_features & HAS_ZONE3) &&
+	    (err = sysfs_create_group(&dev->kobj,
+				      &dme1737_zone3_group))) {
+		goto exit_remove;
+	}
+	if ((data->has_features & HAS_ZONE_HYST) &&
+	    (err = sysfs_create_group(&dev->kobj,
+				      &dme1737_zone_hyst_group))) {
+		goto exit_remove;
+	}
 
 	/* Create fan sysfs attributes */
 	for (ix = 0; ix < ARRAY_SIZE(dme1737_fan_group); ix++) {
-		if (data->has_fan & (1 << ix)) {
+		if (data->has_features & HAS_FAN(ix)) {
 			if ((err = sysfs_create_group(&dev->kobj,
 						&dme1737_fan_group[ix]))) {
 				goto exit_remove;
@@ -1960,14 +2041,14 @@ static int dme1737_create_files(struct device *dev)
 
 	/* Create PWM sysfs attributes */
 	for (ix = 0; ix < ARRAY_SIZE(dme1737_pwm_group); ix++) {
-		if (data->has_pwm & (1 << ix)) {
+		if (data->has_features & HAS_PWM(ix)) {
 			if ((err = sysfs_create_group(&dev->kobj,
 						&dme1737_pwm_group[ix]))) {
 				goto exit_remove;
 			}
-			if (data->type != sch5027 && ix < 3 &&
+			if ((data->has_features & HAS_PWM_MIN) && ix < 3 &&
 			    (err = sysfs_create_file(&dev->kobj,
-						dme1737_pwm_misc_attr[ix]))) {
+					dme1737_auto_pwm_min_attr[ix]))) {
 				goto exit_remove;
 			}
 		}
@@ -1983,21 +2064,30 @@ static int dme1737_create_files(struct device *dev)
 		dme1737_chmod_group(dev, &dme1737_zone_chmod_group,
 				    S_IRUGO | S_IWUSR);
 
-		/* Change permissions of misc sysfs attributes */
-		if (data->type != sch5027) {
-			dme1737_chmod_group(dev, &dme1737_misc_group,
+		/* Change permissions of chip-dependent sysfs attributes */
+		if (data->has_features & HAS_TEMP_OFFSET) {
+			dme1737_chmod_group(dev, &dme1737_temp_offset_group,
+					    S_IRUGO | S_IWUSR);
+		}
+		if (data->has_features & HAS_ZONE3) {
+			dme1737_chmod_group(dev, &dme1737_zone3_chmod_group,
+					    S_IRUGO | S_IWUSR);
+		}
+		if (data->has_features & HAS_ZONE_HYST) {
+			dme1737_chmod_group(dev, &dme1737_zone_hyst_group,
 					    S_IRUGO | S_IWUSR);
 		}
 
 		/* Change permissions of PWM sysfs attributes */
 		for (ix = 0; ix < ARRAY_SIZE(dme1737_pwm_chmod_group); ix++) {
-			if (data->has_pwm & (1 << ix)) {
+			if (data->has_features & HAS_PWM(ix)) {
 				dme1737_chmod_group(dev,
 						&dme1737_pwm_chmod_group[ix],
 						S_IRUGO | S_IWUSR);
-				if (data->type != sch5027 && ix < 3) {
+				if ((data->has_features & HAS_PWM_MIN) &&
+				    ix < 3) {
 					dme1737_chmod_file(dev,
-						dme1737_pwm_misc_attr[ix],
+						dme1737_auto_pwm_min_attr[ix],
 						S_IRUGO | S_IWUSR);
 				}
 			}
@@ -2005,7 +2095,7 @@ static int dme1737_create_files(struct device *dev)
 
 		/* Change permissions of pwm[1-3] if in manual mode */
 		for (ix = 0; ix < 3; ix++) {
-			if ((data->has_pwm & (1 << ix)) &&
+			if ((data->has_features & HAS_PWM(ix)) &&
 			    (PWM_EN_FROM_REG(data->pwm_config[ix]) == 1)) {
 				dme1737_chmod_file(dev,
 						dme1737_pwm_chmod_attr[ix],
@@ -2052,20 +2142,20 @@ static int dme1737_init_device(struct device *dev)
 		return -EFAULT;
 	}
 
-	/* Determine which optional fan and pwm features are enabled/present */
+	/* Determine which optional fan and pwm features are enabled (only
+	 * valid for I2C devices) */
 	if (client) {   /* I2C chip */
 		data->config2 = dme1737_read(data, DME1737_REG_CONFIG2);
 		/* Check if optional fan3 input is enabled */
 		if (data->config2 & 0x04) {
-			data->has_fan |= (1 << 2);
+			data->has_features |= HAS_FAN(2);
 		}
 
 		/* Fan4 and pwm3 are only available if the client's I2C address
 		 * is the default 0x2e. Otherwise the I/Os associated with
 		 * these functions are used for addr enable/select. */
 		if (client->addr == 0x2e) {
-			data->has_fan |= (1 << 3);
-			data->has_pwm |= (1 << 2);
+			data->has_features |= HAS_FAN(3) | HAS_PWM(2);
 		}
 
 		/* Determine which of the optional fan[5-6] and pwm[5-6]
@@ -2077,26 +2167,40 @@ static int dme1737_init_device(struct device *dev)
 			dev_warn(dev, "Failed to query Super-IO for optional "
 				 "features.\n");
 		}
-	} else {   /* ISA chip */
-		/* Fan3 and pwm3 are always available. Fan[4-5] and pwm[5-6]
-		 * don't exist in the ISA chip. */
-		data->has_fan |= (1 << 2);
-		data->has_pwm |= (1 << 2);
 	}
 
-	/* Fan1, fan2, pwm1, and pwm2 are always present */
-	data->has_fan |= 0x03;
-	data->has_pwm |= 0x03;
+	/* Fan[1-2] and pwm[1-2] are present in all chips */
+	data->has_features |= HAS_FAN(0) | HAS_FAN(1) | HAS_PWM(0) | HAS_PWM(1);
+
+	/* Chip-dependent features */
+	switch (data->type) {
+	case dme1737:
+		data->has_features |= HAS_TEMP_OFFSET | HAS_VID | HAS_ZONE3 |
+			HAS_ZONE_HYST | HAS_PWM_MIN;
+		break;
+	case sch311x:
+		data->has_features |= HAS_TEMP_OFFSET | HAS_ZONE3 |
+			HAS_ZONE_HYST | HAS_PWM_MIN | HAS_FAN(2) | HAS_PWM(2);
+		break;
+	case sch5027:
+		data->has_features |= HAS_ZONE3;
+		break;
+	case sch5127:
+		data->has_features |= HAS_FAN(2) | HAS_PWM(2);
+		break;
+	default:
+		break;
+	}
 
 	dev_info(dev, "Optional features: pwm3=%s, pwm5=%s, pwm6=%s, "
 		 "fan3=%s, fan4=%s, fan5=%s, fan6=%s.\n",
-		 (data->has_pwm & (1 << 2)) ? "yes" : "no",
-		 (data->has_pwm & (1 << 4)) ? "yes" : "no",
-		 (data->has_pwm & (1 << 5)) ? "yes" : "no",
-		 (data->has_fan & (1 << 2)) ? "yes" : "no",
-		 (data->has_fan & (1 << 3)) ? "yes" : "no",
-		 (data->has_fan & (1 << 4)) ? "yes" : "no",
-		 (data->has_fan & (1 << 5)) ? "yes" : "no");
+		 (data->has_features & HAS_PWM(2)) ? "yes" : "no",
+		 (data->has_features & HAS_PWM(4)) ? "yes" : "no",
+		 (data->has_features & HAS_PWM(5)) ? "yes" : "no",
+		 (data->has_features & HAS_FAN(2)) ? "yes" : "no",
+		 (data->has_features & HAS_FAN(3)) ? "yes" : "no",
+		 (data->has_features & HAS_FAN(4)) ? "yes" : "no",
+		 (data->has_features & HAS_FAN(5)) ? "yes" : "no");
 
 	reg = dme1737_read(data, DME1737_REG_TACH_PWM);
 	/* Inform if fan-to-pwm mapping differs from the default */
@@ -2122,7 +2226,7 @@ static int dme1737_init_device(struct device *dev)
 		for (ix = 0; ix < 3; ix++) {
 			data->pwm_config[ix] = dme1737_read(data,
 						DME1737_REG_PWM_CONFIG(ix));
-			if ((data->has_pwm & (1 << ix)) &&
+			if ((data->has_features & HAS_PWM(ix)) &&
 			    (PWM_EN_FROM_REG(data->pwm_config[ix]) == -1)) {
 				dev_info(dev, "Switching pwm%d to "
 					 "manual mode.\n", ix + 1);
@@ -2142,7 +2246,7 @@ static int dme1737_init_device(struct device *dev)
 	data->pwm_acz[2] = 4;	/* pwm3 -> zone3 */
 
 	/* Set VRM */
-	if (data->type == dme1737) {
+	if (data->has_features & HAS_VID) {
 		data->vrm = vid_which_vrm();
 	}
 
@@ -2163,10 +2267,10 @@ static int dme1737_i2c_get_features(int sio_cip, struct dme1737_data *data)
 	dme1737_sio_enter(sio_cip);
 
 	/* Check device ID
-	 * The DME1737 can return either 0x78 or 0x77 as its device ID.
-	 * The SCH5027 returns 0x89 as its device ID. */
+	 * We currently know about two kinds of DME1737 and SCH5027. */
 	reg = force_id ? force_id : dme1737_sio_inb(sio_cip, 0x20);
-	if (!(reg == 0x77 || reg == 0x78 || reg == 0x89)) {
+	if (!(reg == DME1737_ID_1 || reg == DME1737_ID_2 ||
+	      reg == SCH5027_ID)) {
 		err = -ENODEV;
 		goto exit;
 	}
@@ -2185,16 +2289,16 @@ static int dme1737_i2c_get_features(int sio_cip, struct dme1737_data *data)
 	 * are enabled and available. Bits [3:2] of registers 0x43-0x46 are set
 	 * to '10' if the respective feature is enabled. */
 	if ((inb(addr + 0x43) & 0x0c) == 0x08) { /* fan6 */
-		data->has_fan |= (1 << 5);
+		data->has_features |= HAS_FAN(5);
 	}
 	if ((inb(addr + 0x44) & 0x0c) == 0x08) { /* pwm6 */
-		data->has_pwm |= (1 << 5);
+		data->has_features |= HAS_PWM(5);
 	}
 	if ((inb(addr + 0x45) & 0x0c) == 0x08) { /* fan5 */
-		data->has_fan |= (1 << 4);
+		data->has_features |= HAS_FAN(4);
 	}
 	if ((inb(addr + 0x46) & 0x0c) == 0x08) { /* pwm5 */
-		data->has_pwm |= (1 << 4);
+		data->has_features |= HAS_PWM(4);
 	}
 
 exit:
@@ -2222,7 +2326,6 @@ static int dme1737_i2c_detect(struct i2c_client *client,
 	if (company == DME1737_COMPANY_SMSC &&
 	    verstep == SCH5027_VERSTEP) {
 		name = "sch5027";
-
 	} else if (company == DME1737_COMPANY_SMSC &&
 		   (verstep & DME1737_VERSTEP_MASK) == DME1737_VERSTEP) {
 		name = "dme1737";
@@ -2329,10 +2432,10 @@ static int __init dme1737_isa_detect(int sio_cip, unsigned short *addr)
 	dme1737_sio_enter(sio_cip);
 
 	/* Check device ID
-	 * We currently know about SCH3112 (0x7c), SCH3114 (0x7d), and
-	 * SCH3116 (0x7f). */
+	 * We currently know about SCH3112, SCH3114, SCH3116, and SCH5127 */
 	reg = force_id ? force_id : dme1737_sio_inb(sio_cip, 0x20);
-	if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
+	if (!(reg == SCH3112_ID || reg == SCH3114_ID || reg == SCH3116_ID ||
+	      reg == SCH5127_ID)) {
 		err = -ENODEV;
 		goto exit;
 	}
@@ -2424,23 +2527,42 @@ static int __devinit dme1737_isa_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, data);
 
 	/* Skip chip detection if module is loaded with force_id parameter */
-	if (!force_id) {
+	switch (force_id) {
+	case SCH3112_ID:
+	case SCH3114_ID:
+	case SCH3116_ID:
+		data->type = sch311x;
+		break;
+	case SCH5127_ID:
+		data->type = sch5127;
+		break;
+	default:
 		company = dme1737_read(data, DME1737_REG_COMPANY);
 		device = dme1737_read(data, DME1737_REG_DEVICE);
 
-		if (!((company == DME1737_COMPANY_SMSC) &&
-		      (device == SCH311X_DEVICE))) {
+		if ((company == DME1737_COMPANY_SMSC) &&
+		    (device == SCH311X_DEVICE)) {
+			data->type = sch311x;
+		} else if ((company == DME1737_COMPANY_SMSC) &&
+			   (device == SCH5127_DEVICE)) {
+			data->type = sch5127;
+		} else {
 			err = -ENODEV;
 			goto exit_kfree;
 		}
 	}
-	data->type = sch311x;
 
-	/* Fill in the remaining client fields and initialize the mutex */
-	data->name = "sch311x";
+	if (data->type == sch5127) {
+		data->name = "sch5127";
+	} else {
+		data->name = "sch311x";
+	}
+
+	/* Initialize the mutex */
 	mutex_init(&data->update_lock);
 
-	dev_info(dev, "Found a SCH311x chip at 0x%04x\n", data->addr);
+	dev_info(dev, "Found a %s chip at 0x%04x\n",
+		 data->type == sch5127 ? "SCH5127" : "SCH311x", data->addr);
 
 	/* Initialize the chip */
 	if ((err = dme1737_init_device(dev))) {