hwmon: (pmbus) Move PMBus drivers to drivers/hwmon/pmbus

Since the number of PMBus drivers is getting large, move them into
directory drivers/hwmon/pmbus to improve readability and scalability.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>

1 files changed, 1567 insertions, 0 deletions

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
new file mode 100644
index 00000000000..8e31a8e2c74
--- /dev/null
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -0,0 +1,1567 @@
+/*
+ * Hardware monitoring driver for PMBus devices
+ *
+ * Copyright (c) 2010, 2011 Ericsson AB.
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/delay.h>
+#include <linux/i2c/pmbus.h>
+#include "pmbus.h"
+
+/*
+ * Constants needed to determine number of sensors, booleans, and labels.
+ */
+#define PMBUS_MAX_INPUT_SENSORS		11	/* 6*volt, 3*curr, 2*power */
+#define PMBUS_VOUT_SENSORS_PER_PAGE	5	/* input, min, max, lcrit,
+						   crit */
+#define PMBUS_IOUT_SENSORS_PER_PAGE	4	/* input, min, max, crit */
+#define PMBUS_POUT_SENSORS_PER_PAGE	4	/* input, cap, max, crit */
+#define PMBUS_MAX_SENSORS_PER_FAN	1	/* input */
+#define PMBUS_MAX_SENSORS_PER_TEMP	5	/* input, min, max, lcrit,
+						   crit */
+
+#define PMBUS_MAX_INPUT_BOOLEANS	7	/* v: min_alarm, max_alarm,
+						   lcrit_alarm, crit_alarm;
+						   c: alarm, crit_alarm;
+						   p: crit_alarm */
+#define PMBUS_VOUT_BOOLEANS_PER_PAGE	4	/* min_alarm, max_alarm,
+						   lcrit_alarm, crit_alarm */
+#define PMBUS_IOUT_BOOLEANS_PER_PAGE	3	/* alarm, lcrit_alarm,
+						   crit_alarm */
+#define PMBUS_POUT_BOOLEANS_PER_PAGE	2	/* alarm, crit_alarm */
+#define PMBUS_MAX_BOOLEANS_PER_FAN	2	/* alarm, fault */
+#define PMBUS_MAX_BOOLEANS_PER_TEMP	4	/* min_alarm, max_alarm,
+						   lcrit_alarm, crit_alarm */
+
+#define PMBUS_MAX_INPUT_LABELS		4	/* vin, vcap, iin, pin */
+
+/*
+ * status, status_vout, status_iout, status_fans, status_fan34, and status_temp
+ * are paged. status_input is unpaged.
+ */
+#define PB_NUM_STATUS_REG	(PMBUS_PAGES * 6 + 1)
+
+/*
+ * Index into status register array, per status register group
+ */
+#define PB_STATUS_BASE		0
+#define PB_STATUS_VOUT_BASE	(PB_STATUS_BASE + PMBUS_PAGES)
+#define PB_STATUS_IOUT_BASE	(PB_STATUS_VOUT_BASE + PMBUS_PAGES)
+#define PB_STATUS_FAN_BASE	(PB_STATUS_IOUT_BASE + PMBUS_PAGES)
+#define PB_STATUS_FAN34_BASE	(PB_STATUS_FAN_BASE + PMBUS_PAGES)
+#define PB_STATUS_INPUT_BASE	(PB_STATUS_FAN34_BASE + PMBUS_PAGES)
+#define PB_STATUS_TEMP_BASE	(PB_STATUS_INPUT_BASE + 1)
+
+struct pmbus_sensor {
+	char name[I2C_NAME_SIZE];	/* sysfs sensor name */
+	struct sensor_device_attribute attribute;
+	u8 page;		/* page number */
+	u8 reg;			/* register */
+	enum pmbus_sensor_classes class;	/* sensor class */
+	bool update;		/* runtime sensor update needed */
+	int data;		/* Sensor data.
+				   Negative if there was a read error */
+};
+
+struct pmbus_boolean {
+	char name[I2C_NAME_SIZE];	/* sysfs boolean name */
+	struct sensor_device_attribute attribute;
+};
+
+struct pmbus_label {
+	char name[I2C_NAME_SIZE];	/* sysfs label name */
+	struct sensor_device_attribute attribute;
+	char label[I2C_NAME_SIZE];	/* label */
+};
+
+struct pmbus_data {
+	struct device *hwmon_dev;
+
+	u32 flags;		/* from platform data */
+
+	int exponent;		/* linear mode: exponent for output voltages */
+
+	const struct pmbus_driver_info *info;
+
+	int max_attributes;
+	int num_attributes;
+	struct attribute **attributes;
+	struct attribute_group group;
+
+	/*
+	 * Sensors cover both sensor and limit registers.
+	 */
+	int max_sensors;
+	int num_sensors;
+	struct pmbus_sensor *sensors;
+	/*
+	 * Booleans are used for alarms.
+	 * Values are determined from status registers.
+	 */
+	int max_booleans;
+	int num_booleans;
+	struct pmbus_boolean *booleans;
+	/*
+	 * Labels are used to map generic names (e.g., "in1")
+	 * to PMBus specific names (e.g., "vin" or "vout1").
+	 */
+	int max_labels;
+	int num_labels;
+	struct pmbus_label *labels;
+
+	struct mutex update_lock;
+	bool valid;
+	unsigned long last_updated;	/* in jiffies */
+
+	/*
+	 * A single status register covers multiple attributes,
+	 * so we keep them all together.
+	 */
+	u8 status[PB_NUM_STATUS_REG];
+
+	u8 currpage;
+};
+
+int pmbus_set_page(struct i2c_client *client, u8 page)
+{
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	int rv = 0;
+	int newpage;
+
+	if (page != data->currpage) {
+		rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
+		newpage = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
+		if (newpage != page)
+			rv = -EINVAL;
+		else
+			data->currpage = page;
+	}
+	return rv;
+}
+EXPORT_SYMBOL_GPL(pmbus_set_page);
+
+static int pmbus_write_byte(struct i2c_client *client, u8 page, u8 value)
+{
+	int rv;
+
+	rv = pmbus_set_page(client, page);
+	if (rv < 0)
+		return rv;
+
+	return i2c_smbus_write_byte(client, value);
+}
+
+static int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg,
+				 u16 word)
+{
+	int rv;
+
+	rv = pmbus_set_page(client, page);
+	if (rv < 0)
+		return rv;
+
+	return i2c_smbus_write_word_data(client, reg, word);
+}
+
+int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg)
+{
+	int rv;
+
+	rv = pmbus_set_page(client, page);
+	if (rv < 0)
+		return rv;
+
+	return i2c_smbus_read_word_data(client, reg);
+}
+EXPORT_SYMBOL_GPL(pmbus_read_word_data);
+
+static int pmbus_read_byte_data(struct i2c_client *client, u8 page, u8 reg)
+{
+	int rv;
+
+	rv = pmbus_set_page(client, page);
+	if (rv < 0)
+		return rv;
+
+	return i2c_smbus_read_byte_data(client, reg);
+}
+
+static void pmbus_clear_fault_page(struct i2c_client *client, int page)
+{
+	pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
+}
+
+void pmbus_clear_faults(struct i2c_client *client)
+{
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	int i;
+
+	for (i = 0; i < data->info->pages; i++)
+		pmbus_clear_fault_page(client, i);
+}
+EXPORT_SYMBOL_GPL(pmbus_clear_faults);
+
+static int pmbus_check_status_cml(struct i2c_client *client, int page)
+{
+	int status, status2;
+
+	status = pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE);
+	if (status < 0 || (status & PB_STATUS_CML)) {
+		status2 = pmbus_read_byte_data(client, page, PMBUS_STATUS_CML);
+		if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
+			return -EINVAL;
+	}
+	return 0;
+}
+
+bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
+{
+	int rv;
+	struct pmbus_data *data = i2c_get_clientdata(client);
+
+	rv = pmbus_read_byte_data(client, page, reg);
+	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
+		rv = pmbus_check_status_cml(client, page);
+	pmbus_clear_fault_page(client, page);
+	return rv >= 0;
+}
+EXPORT_SYMBOL_GPL(pmbus_check_byte_register);
+
+bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
+{
+	int rv;
+	struct pmbus_data *data = i2c_get_clientdata(client);
+
+	rv = pmbus_read_word_data(client, page, reg);
+	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
+		rv = pmbus_check_status_cml(client, page);
+	pmbus_clear_fault_page(client, page);
+	return rv >= 0;
+}
+EXPORT_SYMBOL_GPL(pmbus_check_word_register);
+
+const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
+{
+	struct pmbus_data *data = i2c_get_clientdata(client);
+
+	return data->info;
+}
+EXPORT_SYMBOL_GPL(pmbus_get_driver_info);
+
+/*
+ * _pmbus_read_byte_data() is similar to pmbus_read_byte_data(), but checks if
+ * a device specific mapping funcion exists and calls it if necessary.
+ */
+static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	const struct pmbus_driver_info *info = data->info;
+	int status;
+
+	if (info->read_byte_data) {
+		status = info->read_byte_data(client, page, reg);
+		if (status != -ENODATA)
+			return status;
+	}
+	return pmbus_read_byte_data(client, page, reg);
+}
+
+static struct pmbus_data *pmbus_update_device(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	const struct pmbus_driver_info *info = data->info;
+
+	mutex_lock(&data->update_lock);
+	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+		int i;
+
+		for (i = 0; i < info->pages; i++)
+			data->status[PB_STATUS_BASE + i]
+			    = pmbus_read_byte_data(client, i,
+						   PMBUS_STATUS_BYTE);
+		for (i = 0; i < info->pages; i++) {
+			if (!(info->func[i] & PMBUS_HAVE_STATUS_VOUT))
+				continue;
+			data->status[PB_STATUS_VOUT_BASE + i]
+			  = _pmbus_read_byte_data(client, i, PMBUS_STATUS_VOUT);
+		}
+		for (i = 0; i < info->pages; i++) {
+			if (!(info->func[i] & PMBUS_HAVE_STATUS_IOUT))
+				continue;
+			data->status[PB_STATUS_IOUT_BASE + i]
+			  = _pmbus_read_byte_data(client, i, PMBUS_STATUS_IOUT);
+		}
+		for (i = 0; i < info->pages; i++) {
+			if (!(info->func[i] & PMBUS_HAVE_STATUS_TEMP))
+				continue;
+			data->status[PB_STATUS_TEMP_BASE + i]
+			  = _pmbus_read_byte_data(client, i,
+						  PMBUS_STATUS_TEMPERATURE);
+		}
+		for (i = 0; i < info->pages; i++) {
+			if (!(info->func[i] & PMBUS_HAVE_STATUS_FAN12))
+				continue;
+			data->status[PB_STATUS_FAN_BASE + i]
+			  = _pmbus_read_byte_data(client, i,
+						  PMBUS_STATUS_FAN_12);
+		}
+
+		for (i = 0; i < info->pages; i++) {
+			if (!(info->func[i] & PMBUS_HAVE_STATUS_FAN34))
+				continue;
+			data->status[PB_STATUS_FAN34_BASE + i]
+			  = _pmbus_read_byte_data(client, i,
+						  PMBUS_STATUS_FAN_34);
+		}
+
+		if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
+			data->status[PB_STATUS_INPUT_BASE]
+			  = _pmbus_read_byte_data(client, 0,
+						  PMBUS_STATUS_INPUT);
+
+		for (i = 0; i < data->num_sensors; i++) {
+			struct pmbus_sensor *sensor = &data->sensors[i];
+
+			if (!data->valid || sensor->update)
+				sensor->data
+				    = pmbus_read_word_data(client, sensor->page,
+							   sensor->reg);
+		}
+		pmbus_clear_faults(client);
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+	mutex_unlock(&data->update_lock);
+	return data;
+}
+
+/*
+ * Convert linear sensor values to milli- or micro-units
+ * depending on sensor type.
+ */
+static long pmbus_reg2data_linear(struct pmbus_data *data,
+				  struct pmbus_sensor *sensor)
+{
+	s16 exponent;
+	s32 mantissa;
+	long val;
+
+	if (sensor->class == PSC_VOLTAGE_OUT) {	/* LINEAR16 */
+		exponent = data->exponent;
+		mantissa = (u16) sensor->data;
+	} else {				/* LINEAR11 */
+		exponent = (sensor->data >> 11) & 0x001f;
+		mantissa = sensor->data & 0x07ff;
+
+		if (exponent > 0x0f)
+			exponent |= 0xffe0;	/* sign extend exponent */
+		if (mantissa > 0x03ff)
+			mantissa |= 0xfffff800;	/* sign extend mantissa */
+	}
+
+	val = mantissa;
+
+	/* scale result to milli-units for all sensors except fans */
+	if (sensor->class != PSC_FAN)
+		val = val * 1000L;
+
+	/* scale result to micro-units for power sensors */
+	if (sensor->class == PSC_POWER)
+		val = val * 1000L;
+
+	if (exponent >= 0)
+		val <<= exponent;
+	else
+		val >>= -exponent;
+
+	return val;
+}
+
+/*
+ * Convert direct sensor values to milli- or micro-units
+ * depending on sensor type.
+ */
+static long pmbus_reg2data_direct(struct pmbus_data *data,
+				  struct pmbus_sensor *sensor)
+{
+	long val = (s16) sensor->data;
+	long m, b, R;
+
+	m = data->info->m[sensor->class];
+	b = data->info->b[sensor->class];
+	R = data->info->R[sensor->class];
+
+	if (m == 0)
+		return 0;
+
+	/* X = 1/m * (Y * 10^-R - b) */
+	R = -R;
+	/* scale result to milli-units for everything but fans */
+	if (sensor->class != PSC_FAN) {
+		R += 3;
+		b *= 1000;
+	}
+
+	/* scale result to micro-units for power sensors */
+	if (sensor->class == PSC_POWER) {
+		R += 3;
+		b *= 1000;
+	}
+
+	while (R > 0) {
+		val *= 10;
+		R--;
+	}
+	while (R < 0) {
+		val = DIV_ROUND_CLOSEST(val, 10);
+		R++;
+	}
+
+	return (val - b) / m;
+}
+
+static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
+{
+	long val;
+
+	if (data->info->direct[sensor->class])
+		val = pmbus_reg2data_direct(data, sensor);
+	else
+		val = pmbus_reg2data_linear(data, sensor);
+
+	return val;
+}
+
+#define MAX_MANTISSA	(1023 * 1000)
+#define MIN_MANTISSA	(511 * 1000)
+
+static u16 pmbus_data2reg_linear(struct pmbus_data *data,
+				 enum pmbus_sensor_classes class, long val)
+{
+	s16 exponent = 0, mantissa;
+	bool negative = false;
+
+	/* simple case */
+	if (val == 0)
+		return 0;
+
+	if (class == PSC_VOLTAGE_OUT) {
+		/* LINEAR16 does not support negative voltages */
+		if (val < 0)
+			return 0;
+
+		/*
+		 * For a static exponents, we don't have a choice
+		 * but to adjust the value to it.
+		 */
+		if (data->exponent < 0)
+			val <<= -data->exponent;
+		else
+			val >>= data->exponent;
+		val = DIV_ROUND_CLOSEST(val, 1000);
+		return val & 0xffff;
+	}
+
+	if (val < 0) {
+		negative = true;
+		val = -val;
+	}
+
+	/* Power is in uW. Convert to mW before converting. */
+	if (class == PSC_POWER)
+		val = DIV_ROUND_CLOSEST(val, 1000L);
+
+	/*
+	 * For simplicity, convert fan data to milli-units
+	 * before calculating the exponent.
+	 */
+	if (class == PSC_FAN)
+		val = val * 1000;
+
+	/* Reduce large mantissa until it fits into 10 bit */
+	while (val >= MAX_MANTISSA && exponent < 15) {
+		exponent++;
+		val >>= 1;
+	}
+	/* Increase small mantissa to improve precision */
+	while (val < MIN_MANTISSA && exponent > -15) {
+		exponent--;
+		val <<= 1;
+	}
+
+	/* Convert mantissa from milli-units to units */
+	mantissa = DIV_ROUND_CLOSEST(val, 1000);
+
+	/* Ensure that resulting number is within range */
+	if (mantissa > 0x3ff)
+		mantissa = 0x3ff;
+
+	/* restore sign */
+	if (negative)
+		mantissa = -mantissa;
+
+	/* Convert to 5 bit exponent, 11 bit mantissa */
+	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
+}
+
+static u16 pmbus_data2reg_direct(struct pmbus_data *data,
+				 enum pmbus_sensor_classes class, long val)
+{
+	long m, b, R;
+
+	m = data->info->m[class];
+	b = data->info->b[class];
+	R = data->info->R[class];
+
+	/* Power is in uW. Adjust R and b. */
+	if (class == PSC_POWER) {
+		R -= 3;
+		b *= 1000;
+	}
+
+	/* Calculate Y = (m * X + b) * 10^R */
+	if (class != PSC_FAN) {
+		R -= 3;		/* Adjust R and b for data in milli-units */
+		b *= 1000;
+	}
+	val = val * m + b;
+
+	while (R > 0) {
+		val *= 10;
+		R--;
+	}
+	while (R < 0) {
+		val = DIV_ROUND_CLOSEST(val, 10);
+		R++;
+	}
+
+	return val;
+}
+
+static u16 pmbus_data2reg(struct pmbus_data *data,
+			  enum pmbus_sensor_classes class, long val)
+{
+	u16 regval;
+
+	if (data->info->direct[class])
+		regval = pmbus_data2reg_direct(data, class, val);
+	else
+		regval = pmbus_data2reg_linear(data, class, val);
+
+	return regval;
+}
+
+/*
+ * Return boolean calculated from converted data.
+ * <index> defines a status register index and mask, and optionally
+ * two sensor indexes.
+ * The upper half-word references the two sensors,
+ * two sensor indices.
+ * The upper half-word references the two optional sensors,
+ * the lower half word references status register and mask.
+ * The function returns true if (status[reg] & mask) is true and,
+ * if specified, if v1 >= v2.
+ * To determine if an object exceeds upper limits, specify <v, limit>.
+ * To determine if an object exceeds lower limits, specify <limit, v>.
+ *
+ * For booleans created with pmbus_add_boolean_reg(), only the lower 16 bits of
+ * index are set. s1 and s2 (the sensor index values) are zero in this case.
+ * The function returns true if (status[reg] & mask) is true.
+ *
+ * If the boolean was created with pmbus_add_boolean_cmp(), a comparison against
+ * a specified limit has to be performed to determine the boolean result.
+ * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
+ * sensor values referenced by sensor indices s1 and s2).
+ *
+ * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
+ * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
+ *
+ * If a negative value is stored in any of the referenced registers, this value
+ * reflects an error code which will be returned.
+ */
+static int pmbus_get_boolean(struct pmbus_data *data, int index, int *val)
+{
+	u8 s1 = (index >> 24) & 0xff;
+	u8 s2 = (index >> 16) & 0xff;
+	u8 reg = (index >> 8) & 0xff;
+	u8 mask = index & 0xff;
+	int status;
+	u8 regval;
+
+	status = data->status[reg];
+	if (status < 0)
+		return status;
+
+	regval = status & mask;
+	if (!s1 && !s2)
+		*val = !!regval;
+	else {
+		long v1, v2;
+		struct pmbus_sensor *sensor1, *sensor2;
+
+		sensor1 = &data->sensors[s1];
+		if (sensor1->data < 0)
+			return sensor1->data;
+		sensor2 = &data->sensors[s2];
+		if (sensor2->data < 0)
+			return sensor2->data;
+
+		v1 = pmbus_reg2data(data, sensor1);
+		v2 = pmbus_reg2data(data, sensor2);
+		*val = !!(regval && v1 >= v2);
+	}
+	return 0;
+}
+
+static ssize_t pmbus_show_boolean(struct device *dev,
+				  struct device_attribute *da, char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct pmbus_data *data = pmbus_update_device(dev);
+	int val;
+	int err;
+
+	err = pmbus_get_boolean(data, attr->index, &val);
+	if (err)
+		return err;
+	return snprintf(buf, PAGE_SIZE, "%d\n", val);
+}
+
+static ssize_t pmbus_show_sensor(struct device *dev,
+				 struct device_attribute *da, char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct pmbus_data *data = pmbus_update_device(dev);
+	struct pmbus_sensor *sensor;
+
+	sensor = &data->sensors[attr->index];
+	if (sensor->data < 0)
+		return sensor->data;
+
+	return snprintf(buf, PAGE_SIZE, "%ld\n", pmbus_reg2data(data, sensor));
+}
+
+static ssize_t pmbus_set_sensor(struct device *dev,
+				struct device_attribute *devattr,
+				const char *buf, size_t count)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	struct i2c_client *client = to_i2c_client(dev);
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	struct pmbus_sensor *sensor = &data->sensors[attr->index];
+	ssize_t rv = count;
+	long val = 0;
+	int ret;
+	u16 regval;
+
+	if (strict_strtol(buf, 10, &val) < 0)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	regval = pmbus_data2reg(data, sensor->class, val);
+	ret = pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
+	if (ret < 0)
+		rv = ret;
+	else
+		data->sensors[attr->index].data = regval;
+	mutex_unlock(&data->update_lock);
+	return rv;
+}
+
+static ssize_t pmbus_show_label(struct device *dev,
+				struct device_attribute *da, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+
+	return snprintf(buf, PAGE_SIZE, "%s\n",
+			data->labels[attr->index].label);
+}
+
+#define PMBUS_ADD_ATTR(data, _name, _idx, _mode, _type, _show, _set)	\
+do {									\
+	struct sensor_device_attribute *a				\
+	    = &data->_type##s[data->num_##_type##s].attribute;		\
+	BUG_ON(data->num_attributes >= data->max_attributes);		\
+	sysfs_attr_init(&a->dev_attr.attr);				\
+	a->dev_attr.attr.name = _name;					\
+	a->dev_attr.attr.mode = _mode;					\
+	a->dev_attr.show = _show;					\
+	a->dev_attr.store = _set;					\
+	a->index = _idx;						\
+	data->attributes[data->num_attributes] = &a->dev_attr.attr;	\
+	data->num_attributes++;						\
+} while (0)
+
+#define PMBUS_ADD_GET_ATTR(data, _name, _type, _idx)			\
+	PMBUS_ADD_ATTR(data, _name, _idx, S_IRUGO, _type,		\
+		       pmbus_show_##_type,  NULL)
+
+#define PMBUS_ADD_SET_ATTR(data, _name, _type, _idx)			\
+	PMBUS_ADD_ATTR(data, _name, _idx, S_IWUSR | S_IRUGO, _type,	\
+		       pmbus_show_##_type, pmbus_set_##_type)
+
+static void pmbus_add_boolean(struct pmbus_data *data,
+			      const char *name, const char *type, int seq,
+			      int idx)
+{
+	struct pmbus_boolean *boolean;
+
+	BUG_ON(data->num_booleans >= data->max_booleans);
+
+	boolean = &data->booleans[data->num_booleans];
+
+	snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
+		 name, seq, type);
+	PMBUS_ADD_GET_ATTR(data, boolean->name, boolean, idx);
+	data->num_booleans++;
+}
+
+static void pmbus_add_boolean_reg(struct pmbus_data *data,
+				  const char *name, const char *type,
+				  int seq, int reg, int bit)
+{
+	pmbus_add_boolean(data, name, type, seq, (reg << 8) | bit);
+}
+
+static void pmbus_add_boolean_cmp(struct pmbus_data *data,
+				  const char *name, const char *type,
+				  int seq, int i1, int i2, int reg, int mask)
+{
+	pmbus_add_boolean(data, name, type, seq,
+			  (i1 << 24) | (i2 << 16) | (reg << 8) | mask);
+}
+
+static void pmbus_add_sensor(struct pmbus_data *data,
+			     const char *name, const char *type, int seq,
+			     int page, int reg, enum pmbus_sensor_classes class,
+			     bool update, bool readonly)
+{
+	struct pmbus_sensor *sensor;
+
+	BUG_ON(data->num_sensors >= data->max_sensors);
+
+	sensor = &data->sensors[data->num_sensors];
+	snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
+		 name, seq, type);
+	sensor->page = page;
+	sensor->reg = reg;
+	sensor->class = class;
+	sensor->update = update;
+	if (readonly)
+		PMBUS_ADD_GET_ATTR(data, sensor->name, sensor,
+				   data->num_sensors);
+	else
+		PMBUS_ADD_SET_ATTR(data, sensor->name, sensor,
+				   data->num_sensors);
+	data->num_sensors++;
+}
+
+static void pmbus_add_label(struct pmbus_data *data,
+			    const char *name, int seq,
+			    const char *lstring, int index)
+{
+	struct pmbus_label *label;
+
+	BUG_ON(data->num_labels >= data->max_labels);
+
+	label = &data->labels[data->num_labels];
+	snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
+	if (!index)
+		strncpy(label->label, lstring, sizeof(label->label) - 1);
+	else
+		snprintf(label->label, sizeof(label->label), "%s%d", lstring,
+			 index);
+
+	PMBUS_ADD_GET_ATTR(data, label->name, label, data->num_labels);
+	data->num_labels++;
+}
+
+/*
+ * Determine maximum number of sensors, booleans, and labels.
+ * To keep things simple, only make a rough high estimate.
+ */
+static void pmbus_find_max_attr(struct i2c_client *client,
+				struct pmbus_data *data)
+{
+	const struct pmbus_driver_info *info = data->info;
+	int page, max_sensors, max_booleans, max_labels;
+
+	max_sensors = PMBUS_MAX_INPUT_SENSORS;
+	max_booleans = PMBUS_MAX_INPUT_BOOLEANS;
+	max_labels = PMBUS_MAX_INPUT_LABELS;
+
+	for (page = 0; page < info->pages; page++) {
+		if (info->func[page] & PMBUS_HAVE_VOUT) {
+			max_sensors += PMBUS_VOUT_SENSORS_PER_PAGE;
+			max_booleans += PMBUS_VOUT_BOOLEANS_PER_PAGE;
+			max_labels++;
+		}
+		if (info->func[page] & PMBUS_HAVE_IOUT) {
+			max_sensors += PMBUS_IOUT_SENSORS_PER_PAGE;
+			max_booleans += PMBUS_IOUT_BOOLEANS_PER_PAGE;
+			max_labels++;
+		}
+		if (info->func[page] & PMBUS_HAVE_POUT) {
+			max_sensors += PMBUS_POUT_SENSORS_PER_PAGE;
+			max_booleans += PMBUS_POUT_BOOLEANS_PER_PAGE;
+			max_labels++;
+		}
+		if (info->func[page] & PMBUS_HAVE_FAN12) {
+			max_sensors += 2 * PMBUS_MAX_SENSORS_PER_FAN;
+			max_booleans += 2 * PMBUS_MAX_BOOLEANS_PER_FAN;
+		}
+		if (info->func[page] & PMBUS_HAVE_FAN34) {
+			max_sensors += 2 * PMBUS_MAX_SENSORS_PER_FAN;
+			max_booleans += 2 * PMBUS_MAX_BOOLEANS_PER_FAN;
+		}
+		if (info->func[page] & PMBUS_HAVE_TEMP) {
+			max_sensors += PMBUS_MAX_SENSORS_PER_TEMP;
+			max_booleans += PMBUS_MAX_BOOLEANS_PER_TEMP;
+		}
+		if (info->func[page] & PMBUS_HAVE_TEMP2) {
+			max_sensors += PMBUS_MAX_SENSORS_PER_TEMP;
+			max_booleans += PMBUS_MAX_BOOLEANS_PER_TEMP;
+		}
+		if (info->func[page] & PMBUS_HAVE_TEMP3) {
+			max_sensors += PMBUS_MAX_SENSORS_PER_TEMP;
+			max_booleans += PMBUS_MAX_BOOLEANS_PER_TEMP;
+		}
+	}
+	data->max_sensors = max_sensors;
+	data->max_booleans = max_booleans;
+	data->max_labels = max_labels;
+	data->max_attributes = max_sensors + max_booleans + max_labels;
+}
+
+/*
+ * Search for attributes. Allocate sensors, booleans, and labels as needed.
+ */
+
+/*
+ * The pmbus_limit_attr structure describes a single limit attribute
+ * and its associated alarm attribute.
+ */
+struct pmbus_limit_attr {
+	u8 reg;			/* Limit register */
+	const char *attr;	/* Attribute name */
+	const char *alarm;	/* Alarm attribute name */
+	u32 sbit;		/* Alarm attribute status bit */
+};
+
+/*
+ * The pmbus_sensor_attr structure describes one sensor attribute. This
+ * description includes a reference to the associated limit attributes.
+ */
+struct pmbus_sensor_attr {
+	u8 reg;				/* sensor register */
+	enum pmbus_sensor_classes class;/* sensor class */
+	const char *label;		/* sensor label */
+	bool paged;			/* true if paged sensor */
+	bool update;			/* true if update needed */
+	bool compare;			/* true if compare function needed */
+	u32 func;			/* sensor mask */
+	u32 sfunc;			/* sensor status mask */
+	int sbase;			/* status base register */
+	u32 gbit;			/* generic status bit */
+	const struct pmbus_limit_attr *limit;/* limit registers */
+	int nlimit;			/* # of limit registers */
+};
+
+/*
+ * Add a set of limit attributes and, if supported, the associated
+ * alarm attributes.
+ */
+static bool pmbus_add_limit_attrs(struct i2c_client *client,
+				  struct pmbus_data *data,
+				  const struct pmbus_driver_info *info,
+				  const char *name, int index, int page,
+				  int cbase,
+				  const struct pmbus_sensor_attr *attr)
+{
+	const struct pmbus_limit_attr *l = attr->limit;
+	int nlimit = attr->nlimit;
+	bool have_alarm = false;
+	int i, cindex;
+
+	for (i = 0; i < nlimit; i++) {
+		if (pmbus_check_word_register(client, page, l->reg)) {
+			cindex = data->num_sensors;
+			pmbus_add_sensor(data, name, l->attr, index, page,
+					 l->reg, attr->class, attr->update,
+					 false);
+			if (info->func[page] & attr->sfunc) {
+				if (attr->compare) {
+					pmbus_add_boolean_cmp(data, name,
+						l->alarm, index,
+						cbase, cindex,
+						attr->sbase + page, l->sbit);
+				} else {
+					pmbus_add_boolean_reg(data, name,
+						l->alarm, index,
+						attr->sbase + page, l->sbit);
+				}
+				have_alarm = true;
+			}
+		}
+		l++;
+	}
+	return have_alarm;
+}
+
+static void pmbus_add_sensor_attrs_one(struct i2c_client *client,
+				       struct pmbus_data *data,
+				       const struct pmbus_driver_info *info,
+				       const char *name,
+				       int index, int page,
+				       const struct pmbus_sensor_attr *attr)
+{
+	bool have_alarm;
+	int cbase = data->num_sensors;
+
+	if (attr->label)
+		pmbus_add_label(data, name, index, attr->label,
+				attr->paged ? page + 1 : 0);
+	pmbus_add_sensor(data, name, "input", index, page, attr->reg,
+			 attr->class, true, true);
+	if (attr->sfunc) {
+		have_alarm = pmbus_add_limit_attrs(client, data, info, name,
+						   index, page, cbase, attr);
+		/*
+		 * Add generic alarm attribute only if there are no individual
+		 * alarm attributes, and if there is a global alarm bit.
+		 */
+		if (!have_alarm && attr->gbit)
+			pmbus_add_boolean_reg(data, name, "alarm", index,
+					      PB_STATUS_BASE + page,
+					      attr->gbit);
+	}
+}
+
+static void pmbus_add_sensor_attrs(struct i2c_client *client,
+				   struct pmbus_data *data,
+				   const char *name,
+				   const struct pmbus_sensor_attr *attrs,
+				   int nattrs)
+{
+	const struct pmbus_driver_info *info = data->info;
+	int index, i;
+
+	index = 1;
+	for (i = 0; i < nattrs; i++) {
+		int page, pages;
+
+		pages = attrs->paged ? info->pages : 1;
+		for (page = 0; page < pages; page++) {
+			if (!(info->func[page] & attrs->func))
+				continue;
+			pmbus_add_sensor_attrs_one(client, data, info, name,
+						   index, page, attrs);
+			index++;
+		}
+		attrs++;
+	}
+}
+
+static const struct pmbus_limit_attr vin_limit_attrs[] = {
+	{
+		.reg = PMBUS_VIN_UV_WARN_LIMIT,
+		.attr = "min",
+		.alarm = "min_alarm",
+		.sbit = PB_VOLTAGE_UV_WARNING,
+	}, {
+		.reg = PMBUS_VIN_UV_FAULT_LIMIT,
+		.attr = "lcrit",
+		.alarm = "lcrit_alarm",
+		.sbit = PB_VOLTAGE_UV_FAULT,
+	}, {
+		.reg = PMBUS_VIN_OV_WARN_LIMIT,
+		.attr = "max",
+		.alarm = "max_alarm",
+		.sbit = PB_VOLTAGE_OV_WARNING,
+	}, {
+		.reg = PMBUS_VIN_OV_FAULT_LIMIT,
+		.attr = "crit",
+		.alarm = "crit_alarm",
+		.sbit = PB_VOLTAGE_OV_FAULT,
+	},
+};
+
+static const struct pmbus_limit_attr vout_limit_attrs[] = {
+	{
+		.reg = PMBUS_VOUT_UV_WARN_LIMIT,
+		.attr = "min",
+		.alarm = "min_alarm",
+		.sbit = PB_VOLTAGE_UV_WARNING,
+	}, {
+		.reg = PMBUS_VOUT_UV_FAULT_LIMIT,
+		.attr = "lcrit",
+		.alarm = "lcrit_alarm",
+		.sbit = PB_VOLTAGE_UV_FAULT,
+	}, {
+		.reg = PMBUS_VOUT_OV_WARN_LIMIT,
+		.attr = "max",
+		.alarm = "max_alarm",
+		.sbit = PB_VOLTAGE_OV_WARNING,
+	}, {
+		.reg = PMBUS_VOUT_OV_FAULT_LIMIT,
+		.attr = "crit",
+		.alarm = "crit_alarm",
+		.sbit = PB_VOLTAGE_OV_FAULT,
+	}
+};
+
+static const struct pmbus_sensor_attr voltage_attributes[] = {
+	{
+		.reg = PMBUS_READ_VIN,
+		.class = PSC_VOLTAGE_IN,
+		.label = "vin",
+		.func = PMBUS_HAVE_VIN,
+		.sfunc = PMBUS_HAVE_STATUS_INPUT,
+		.sbase = PB_STATUS_INPUT_BASE,
+		.gbit = PB_STATUS_VIN_UV,
+		.limit = vin_limit_attrs,
+		.nlimit = ARRAY_SIZE(vin_limit_attrs),
+	}, {
+		.reg = PMBUS_READ_VCAP,
+		.class = PSC_VOLTAGE_IN,
+		.label = "vcap",
+		.func = PMBUS_HAVE_VCAP,
+	}, {
+		.reg = PMBUS_READ_VOUT,
+		.class = PSC_VOLTAGE_OUT,
+		.label = "vout",
+		.paged = true,
+		.func = PMBUS_HAVE_VOUT,
+		.sfunc = PMBUS_HAVE_STATUS_VOUT,
+		.sbase = PB_STATUS_VOUT_BASE,
+		.gbit = PB_STATUS_VOUT_OV,
+		.limit = vout_limit_attrs,
+		.nlimit = ARRAY_SIZE(vout_limit_attrs),
+	}
+};
+
+/* Current attributes */
+
+static const struct pmbus_limit_attr iin_limit_attrs[] = {
+	{
+		.reg = PMBUS_IIN_OC_WARN_LIMIT,
+		.attr = "max",
+		.alarm = "max_alarm",
+		.sbit = PB_IIN_OC_WARNING,
+	}, {
+		.reg = PMBUS_IIN_OC_FAULT_LIMIT,
+		.attr = "crit",
+		.alarm = "crit_alarm",
+		.sbit = PB_IIN_OC_FAULT,
+	}
+};
+
+static const struct pmbus_limit_attr iout_limit_attrs[] = {
+	{
+		.reg = PMBUS_IOUT_OC_WARN_LIMIT,
+		.attr = "max",
+		.alarm = "max_alarm",
+		.sbit = PB_IOUT_OC_WARNING,
+	}, {
+		.reg = PMBUS_IOUT_UC_FAULT_LIMIT,
+		.attr = "lcrit",
+		.alarm = "lcrit_alarm",
+		.sbit = PB_IOUT_UC_FAULT,
+	}, {
+		.reg = PMBUS_IOUT_OC_FAULT_LIMIT,
+		.attr = "crit",
+		.alarm = "crit_alarm",
+		.sbit = PB_IOUT_OC_FAULT,
+	}
+};
+
+static const struct pmbus_sensor_attr current_attributes[] = {
+	{
+		.reg = PMBUS_READ_IIN,
+		.class = PSC_CURRENT_IN,
+		.label = "iin",
+		.func = PMBUS_HAVE_IIN,
+		.sfunc = PMBUS_HAVE_STATUS_INPUT,
+		.sbase = PB_STATUS_INPUT_BASE,
+		.limit = iin_limit_attrs,
+		.nlimit = ARRAY_SIZE(iin_limit_attrs),
+	}, {
+		.reg = PMBUS_READ_IOUT,
+		.class = PSC_CURRENT_OUT,
+		.label = "iout",
+		.paged = true,
+		.func = PMBUS_HAVE_IOUT,
+		.sfunc = PMBUS_HAVE_STATUS_IOUT,
+		.sbase = PB_STATUS_IOUT_BASE,
+		.gbit = PB_STATUS_IOUT_OC,
+		.limit = iout_limit_attrs,
+		.nlimit = ARRAY_SIZE(iout_limit_attrs),
+	}
+};
+
+/* Power attributes */
+
+static const struct pmbus_limit_attr pin_limit_attrs[] = {
+	{
+		.reg = PMBUS_PIN_OP_WARN_LIMIT,
+		.attr = "max",
+		.alarm = "alarm",
+		.sbit = PB_PIN_OP_WARNING,
+	}
+};
+
+static const struct pmbus_limit_attr pout_limit_attrs[] = {
+	{
+		.reg = PMBUS_POUT_MAX,
+		.attr = "cap",
+		.alarm = "cap_alarm",
+		.sbit = PB_POWER_LIMITING,
+	}, {
+		.reg = PMBUS_POUT_OP_WARN_LIMIT,<