hwmon: Driver for Nuvoton NCT6775F, NCT6776F, and NCT6779D

This driver will replace the w83627ehf driver for NCT6775F and NCT6776F,
and provides support for NCT6779D.

This patch provides support for voltage monitor attributes.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 1021 insertions, 0 deletions

diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c
new file mode 100644
index 000000000000..f75cd8231534
--- /dev/null
+++ b/drivers/hwmon/nct6775.c
@@ -0,0 +1,1021 @@
+/*
+ * nct6775 - Driver for the hardware monitoring functionality of
+ *	       Nuvoton NCT677x Super-I/O chips
+ *
+ * Copyright (C) 2012  Guenter Roeck <linux@roeck-us.net>
+ *
+ * Derived from w83627ehf driver
+ * Copyright (C) 2005-2012  Jean Delvare <khali@linux-fr.org>
+ * Copyright (C) 2006  Yuan Mu (Winbond),
+ *		       Rudolf Marek <r.marek@assembler.cz>
+ *		       David Hubbard <david.c.hubbard@gmail.com>
+ *		       Daniel J Blueman <daniel.blueman@gmail.com>
+ * Copyright (C) 2010  Sheng-Yuan Huang (Nuvoton) (PS00)
+ *
+ * Shamelessly ripped from the w83627hf driver
+ * Copyright (C) 2003  Mark Studebaker
+ *
+ * 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.
+ *
+ *
+ * Supports the following chips:
+ *
+ * Chip        #vin    #fan    #pwm    #temp  chip IDs       man ID
+ * nct6775f     9      4       3       6+3    0xb470 0xc1    0x5ca3
+ * nct6776f     9      5       3       6+3    0xc330 0xc1    0x5ca3
+ * nct6779d    15      5       5       2+6    0xc560 0xc1    0x5ca3
+ *
+ * #temp lists the number of monitored temperature sources (first value) plus
+ * the number of directly connectable temperature sensors (second value).
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/platform_device.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/hwmon-vid.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/acpi.h>
+#include <linux/io.h>
+#include "lm75.h"
+
+enum kinds { nct6775, nct6776, nct6779 };
+
+/* used to set data->name = nct6775_device_names[data->sio_kind] */
+static const char * const nct6775_device_names[] = {
+	"nct6775",
+	"nct6776",
+	"nct6779",
+};
+
+static unsigned short force_id;
+module_param(force_id, ushort, 0);
+MODULE_PARM_DESC(force_id, "Override the detected device ID");
+
+#define DRVNAME "nct6775"
+
+/*
+ * Super-I/O constants and functions
+ */
+
+#define NCT6775_LD_HWM		0x0b
+#define NCT6775_LD_VID		0x0d
+
+#define SIO_REG_LDSEL		0x07	/* Logical device select */
+#define SIO_REG_DEVID		0x20	/* Device ID (2 bytes) */
+#define SIO_REG_ENABLE		0x30	/* Logical device enable */
+#define SIO_REG_ADDR		0x60	/* Logical device address (2 bytes) */
+
+#define SIO_NCT6775_ID		0xb470
+#define SIO_NCT6776_ID		0xc330
+#define SIO_NCT6779_ID		0xc560
+#define SIO_ID_MASK		0xFFF0
+
+static inline void
+superio_outb(int ioreg, int reg, int val)
+{
+	outb(reg, ioreg);
+	outb(val, ioreg + 1);
+}
+
+static inline int
+superio_inb(int ioreg, int reg)
+{
+	outb(reg, ioreg);
+	return inb(ioreg + 1);
+}
+
+static inline void
+superio_select(int ioreg, int ld)
+{
+	outb(SIO_REG_LDSEL, ioreg);
+	outb(ld, ioreg + 1);
+}
+
+static inline int
+superio_enter(int ioreg)
+{
+	/*
+	 * Try to reserve <ioreg> and <ioreg + 1> for exclusive access.
+	 */
+	if (!request_muxed_region(ioreg, 2, DRVNAME))
+		return -EBUSY;
+
+	outb(0x87, ioreg);
+	outb(0x87, ioreg);
+
+	return 0;
+}
+
+static inline void
+superio_exit(int ioreg)
+{
+	outb(0xaa, ioreg);
+	outb(0x02, ioreg);
+	outb(0x02, ioreg + 1);
+	release_region(ioreg, 2);
+}
+
+/*
+ * ISA constants
+ */
+
+#define IOREGION_ALIGNMENT	(~7)
+#define IOREGION_OFFSET		5
+#define IOREGION_LENGTH		2
+#define ADDR_REG_OFFSET		0
+#define DATA_REG_OFFSET		1
+
+#define NCT6775_REG_BANK	0x4E
+#define NCT6775_REG_CONFIG	0x40
+
+/*
+ * Not currently used:
+ * REG_MAN_ID has the value 0x5ca3 for all supported chips.
+ * REG_CHIP_ID == 0x88/0xa1/0xc1 depending on chip model.
+ * REG_MAN_ID is at port 0x4f
+ * REG_CHIP_ID is at port 0x58
+ */
+
+#define NUM_REG_ALARM	4	/* Max number of alarm registers */
+
+/* Common and NCT6775 specific data */
+
+/* Voltage min/max registers for nr=7..14 are in bank 5 */
+
+static const u16 NCT6775_REG_IN_MAX[] = {
+	0x2b, 0x2d, 0x2f, 0x31, 0x33, 0x35, 0x37, 0x554, 0x556, 0x558, 0x55a,
+	0x55c, 0x55e, 0x560, 0x562 };
+static const u16 NCT6775_REG_IN_MIN[] = {
+	0x2c, 0x2e, 0x30, 0x32, 0x34, 0x36, 0x38, 0x555, 0x557, 0x559, 0x55b,
+	0x55d, 0x55f, 0x561, 0x563 };
+static const u16 NCT6775_REG_IN[] = {
+	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x550, 0x551, 0x552
+};
+
+#define NCT6775_REG_VBAT		0x5D
+
+static const u16 NCT6775_REG_ALARM[NUM_REG_ALARM] = { 0x459, 0x45A, 0x45B };
+
+/* 0..15 voltages, 16..23 fans, 24..31 temperatures */
+
+static const s8 NCT6775_ALARM_BITS[] = {
+	0, 1, 2, 3, 8, 21, 20, 16,	/* in0.. in7 */
+	17, -1, -1, -1, -1, -1, -1,	/* in8..in14 */
+	-1,				/* unused */
+	6, 7, 11, 10, 23,		/* fan1..fan5 */
+	-1, -1, -1,			/* unused */
+	4, 5, 13, -1, -1, -1,		/* temp1..temp6 */
+	12, -1 };			/* intrusion0, intrusion1 */
+
+/* NCT6776 specific data */
+
+static const s8 NCT6776_ALARM_BITS[] = {
+	0, 1, 2, 3, 8, 21, 20, 16,	/* in0.. in7 */
+	17, -1, -1, -1, -1, -1, -1,	/* in8..in14 */
+	-1,				/* unused */
+	6, 7, 11, 10, 23,		/* fan1..fan5 */
+	-1, -1, -1,			/* unused */
+	4, 5, 13, -1, -1, -1,		/* temp1..temp6 */
+	12, 9 };			/* intrusion0, intrusion1 */
+
+/* NCT6779 specific data */
+
+static const u16 NCT6779_REG_IN[] = {
+	0x480, 0x481, 0x482, 0x483, 0x484, 0x485, 0x486, 0x487,
+	0x488, 0x489, 0x48a, 0x48b, 0x48c, 0x48d, 0x48e };
+
+static const u16 NCT6779_REG_ALARM[NUM_REG_ALARM] = {
+	0x459, 0x45A, 0x45B, 0x568 };
+
+static const s8 NCT6779_ALARM_BITS[] = {
+	0, 1, 2, 3, 8, 21, 20, 16,	/* in0.. in7 */
+	17, 24, 25, 26, 27, 28, 29,	/* in8..in14 */
+	-1,				/* unused */
+	6, 7, 11, 10, 23,		/* fan1..fan5 */
+	-1, -1, -1,			/* unused */
+	4, 5, 13, -1, -1, -1,		/* temp1..temp6 */
+	12, 9 };			/* intrusion0, intrusion1 */
+
+/*
+ * Conversions
+ */
+
+/*
+ * Some of the voltage inputs have internal scaling, the tables below
+ * contain 8 (the ADC LSB in mV) * scaling factor * 100
+ */
+static const u16 scale_in[15] = {
+	800, 800, 1600, 1600, 800, 800, 800, 1600, 1600, 800, 800, 800, 800,
+	800, 800
+};
+
+static inline long in_from_reg(u8 reg, u8 nr)
+{
+	return DIV_ROUND_CLOSEST(reg * scale_in[nr], 100);
+}
+
+static inline u8 in_to_reg(u32 val, u8 nr)
+{
+	return clamp_val(DIV_ROUND_CLOSEST(val * 100, scale_in[nr]), 0, 255);
+}
+
+/*
+ * Data structures and manipulation thereof
+ */
+
+struct nct6775_data {
+	int addr;	/* IO base of hw monitor block */
+	enum kinds kind;
+	const char *name;
+
+	struct device *hwmon_dev;
+	struct mutex lock;
+
+	u16 REG_CONFIG;
+	u16 REG_VBAT;
+
+	const s8 *ALARM_BITS;
+
+	const u16 *REG_VIN;
+	const u16 *REG_IN_MINMAX[2];
+
+	const u16 *REG_ALARM;
+
+	struct mutex update_lock;
+	bool valid;		/* true if following fields are valid */
+	unsigned long last_updated;	/* In jiffies */
+
+	/* Register values */
+	u8 bank;		/* current register bank */
+	u8 in_num;		/* number of in inputs we have */
+	u8 in[15][3];		/* [0]=in, [1]=in_max, [2]=in_min */
+
+	u64 alarms;
+
+	u8 vid;
+	u8 vrm;
+
+	u16 have_in;
+};
+
+struct nct6775_sio_data {
+	int sioreg;
+	enum kinds kind;
+};
+
+static bool is_word_sized(struct nct6775_data *data, u16 reg)
+{
+	switch (data->kind) {
+	case nct6775:
+		return (((reg & 0xff00) == 0x100 ||
+		    (reg & 0xff00) == 0x200) &&
+		   ((reg & 0x00ff) == 0x50 ||
+		    (reg & 0x00ff) == 0x53 ||
+		    (reg & 0x00ff) == 0x55)) ||
+		  (reg & 0xfff0) == 0x630 ||
+		  reg == 0x640 || reg == 0x642 ||
+		  reg == 0x662 ||
+		  ((reg & 0xfff0) == 0x650 && (reg & 0x000f) >= 0x06) ||
+		  reg == 0x73 || reg == 0x75 || reg == 0x77;
+	case nct6776:
+		return (((reg & 0xff00) == 0x100 ||
+		    (reg & 0xff00) == 0x200) &&
+		   ((reg & 0x00ff) == 0x50 ||
+		    (reg & 0x00ff) == 0x53 ||
+		    (reg & 0x00ff) == 0x55)) ||
+		  (reg & 0xfff0) == 0x630 ||
+		  reg == 0x402 ||
+		  reg == 0x640 || reg == 0x642 ||
+		  ((reg & 0xfff0) == 0x650 && (reg & 0x000f) >= 0x06) ||
+		  reg == 0x73 || reg == 0x75 || reg == 0x77;
+	case nct6779:
+		return reg == 0x150 || reg == 0x153 || reg == 0x155 ||
+		  ((reg & 0xfff0) == 0x4b0 && (reg & 0x000f) < 0x09) ||
+		  reg == 0x402 ||
+		  reg == 0x63a || reg == 0x63c || reg == 0x63e ||
+		  reg == 0x640 || reg == 0x642 ||
+		  reg == 0x73 || reg == 0x75 || reg == 0x77 || reg == 0x79 ||
+		  reg == 0x7b;
+	}
+	return false;
+}
+
+/*
+ * On older chips, only registers 0x50-0x5f are banked.
+ * On more recent chips, all registers are banked.
+ * Assume that is the case and set the bank number for each access.
+ * Cache the bank number so it only needs to be set if it changes.
+ */
+static inline void nct6775_set_bank(struct nct6775_data *data, u16 reg)
+{
+	u8 bank = reg >> 8;
+	if (data->bank != bank) {
+		outb_p(NCT6775_REG_BANK, data->addr + ADDR_REG_OFFSET);
+		outb_p(bank, data->addr + DATA_REG_OFFSET);
+		data->bank = bank;
+	}
+}
+
+static u16 nct6775_read_value(struct nct6775_data *data, u16 reg)
+{
+	int res, word_sized = is_word_sized(data, reg);
+
+	mutex_lock(&data->lock);
+
+	nct6775_set_bank(data, reg);
+	outb_p(reg & 0xff, data->addr + ADDR_REG_OFFSET);
+	res = inb_p(data->addr + DATA_REG_OFFSET);
+	if (word_sized) {
+		outb_p((reg & 0xff) + 1,
+		       data->addr + ADDR_REG_OFFSET);
+		res = (res << 8) + inb_p(data->addr + DATA_REG_OFFSET);
+	}
+
+	mutex_unlock(&data->lock);
+	return res;
+}
+
+static int nct6775_write_value(struct nct6775_data *data, u16 reg, u16 value)
+{
+	int word_sized = is_word_sized(data, reg);
+
+	mutex_lock(&data->lock);
+
+	nct6775_set_bank(data, reg);
+	outb_p(reg & 0xff, data->addr + ADDR_REG_OFFSET);
+	if (word_sized) {
+		outb_p(value >> 8, data->addr + DATA_REG_OFFSET);
+		outb_p((reg & 0xff) + 1,
+		       data->addr + ADDR_REG_OFFSET);
+	}
+	outb_p(value & 0xff, data->addr + DATA_REG_OFFSET);
+
+	mutex_unlock(&data->lock);
+	return 0;
+}
+
+static struct nct6775_data *nct6775_update_device(struct device *dev)
+{
+	struct nct6775_data *data = dev_get_drvdata(dev);
+	int i;
+
+	mutex_lock(&data->update_lock);
+
+	if (time_after(jiffies, data->last_updated + HZ + HZ/2)
+	    || !data->valid) {
+		/* Measured voltages and limits */
+		for (i = 0; i < data->in_num; i++) {
+			if (!(data->have_in & (1 << i)))
+				continue;
+
+			data->in[i][0] = nct6775_read_value(data,
+							    data->REG_VIN[i]);
+			data->in[i][1] = nct6775_read_value(data,
+					  data->REG_IN_MINMAX[0][i]);
+			data->in[i][2] = nct6775_read_value(data,
+					  data->REG_IN_MINMAX[1][i]);
+		}
+
+		data->alarms = 0;
+		for (i = 0; i < NUM_REG_ALARM; i++) {
+			u8 alarm;
+			if (!data->REG_ALARM[i])
+				continue;
+			alarm = nct6775_read_value(data, data->REG_ALARM[i]);
+			data->alarms |= ((u64)alarm) << (i << 3);
+		}
+
+		data->last_updated = jiffies;
+		data->valid = true;
+	}
+
+	mutex_unlock(&data->update_lock);
+	return data;
+}
+
+/*
+ * Sysfs callback functions
+ */
+static ssize_t
+show_in_reg(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct nct6775_data *data = nct6775_update_device(dev);
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+	int nr = sattr->nr;
+	int index = sattr->index;
+	return sprintf(buf, "%ld\n", in_from_reg(data->in[nr][index], nr));
+}
+
+static ssize_t
+store_in_reg(struct device *dev, struct device_attribute *attr, const char *buf,
+	     size_t count)
+{
+	struct nct6775_data *data = dev_get_drvdata(dev);
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+	int nr = sattr->nr;
+	int index = sattr->index;
+	unsigned long val;
+	int err = kstrtoul(buf, 10, &val);
+	if (err < 0)
+		return err;
+	mutex_lock(&data->update_lock);
+	data->in[nr][index] = in_to_reg(val, nr);
+	nct6775_write_value(data, data->REG_IN_MINMAX[index-1][nr],
+			    data->in[nr][index]);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t
+show_alarm(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct nct6775_data *data = nct6775_update_device(dev);
+	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
+	int nr = data->ALARM_BITS[sattr->index];
+	return sprintf(buf, "%u\n",
+		       (unsigned int)((data->alarms >> nr) & 0x01));
+}
+
+static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO, show_in_reg, NULL, 0, 0);
+static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO, show_in_reg, NULL, 1, 0);
+static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO, show_in_reg, NULL, 2, 0);
+static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO, show_in_reg, NULL, 3, 0);
+static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO, show_in_reg, NULL, 4, 0);
+static SENSOR_DEVICE_ATTR_2(in5_input, S_IRUGO, show_in_reg, NULL, 5, 0);
+static SENSOR_DEVICE_ATTR_2(in6_input, S_IRUGO, show_in_reg, NULL, 6, 0);
+static SENSOR_DEVICE_ATTR_2(in7_input, S_IRUGO, show_in_reg, NULL, 7, 0);
+static SENSOR_DEVICE_ATTR_2(in8_input, S_IRUGO, show_in_reg, NULL, 8, 0);
+static SENSOR_DEVICE_ATTR_2(in9_input, S_IRUGO, show_in_reg, NULL, 9, 0);
+static SENSOR_DEVICE_ATTR_2(in10_input, S_IRUGO, show_in_reg, NULL, 10, 0);
+static SENSOR_DEVICE_ATTR_2(in11_input, S_IRUGO, show_in_reg, NULL, 11, 0);
+static SENSOR_DEVICE_ATTR_2(in12_input, S_IRUGO, show_in_reg, NULL, 12, 0);
+static SENSOR_DEVICE_ATTR_2(in13_input, S_IRUGO, show_in_reg, NULL, 13, 0);
+static SENSOR_DEVICE_ATTR_2(in14_input, S_IRUGO, show_in_reg, NULL, 14, 0);
+
+static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
+static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 4);
+static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 5);
+static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, show_alarm, NULL, 6);
+static SENSOR_DEVICE_ATTR(in7_alarm, S_IRUGO, show_alarm, NULL, 7);
+static SENSOR_DEVICE_ATTR(in8_alarm, S_IRUGO, show_alarm, NULL, 8);
+static SENSOR_DEVICE_ATTR(in9_alarm, S_IRUGO, show_alarm, NULL, 9);
+static SENSOR_DEVICE_ATTR(in10_alarm, S_IRUGO, show_alarm, NULL, 10);
+static SENSOR_DEVICE_ATTR(in11_alarm, S_IRUGO, show_alarm, NULL, 11);
+static SENSOR_DEVICE_ATTR(in12_alarm, S_IRUGO, show_alarm, NULL, 12);
+static SENSOR_DEVICE_ATTR(in13_alarm, S_IRUGO, show_alarm, NULL, 13);
+static SENSOR_DEVICE_ATTR(in14_alarm, S_IRUGO, show_alarm, NULL, 14);
+
+static SENSOR_DEVICE_ATTR_2(in0_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 0, 1);
+static SENSOR_DEVICE_ATTR_2(in1_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 1, 1);
+static SENSOR_DEVICE_ATTR_2(in2_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 2, 1);
+static SENSOR_DEVICE_ATTR_2(in3_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 3, 1);
+static SENSOR_DEVICE_ATTR_2(in4_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 4, 1);
+static SENSOR_DEVICE_ATTR_2(in5_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 5, 1);
+static SENSOR_DEVICE_ATTR_2(in6_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 6, 1);
+static SENSOR_DEVICE_ATTR_2(in7_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 7, 1);
+static SENSOR_DEVICE_ATTR_2(in8_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 8, 1);
+static SENSOR_DEVICE_ATTR_2(in9_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 9, 1);
+static SENSOR_DEVICE_ATTR_2(in10_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 10, 1);
+static SENSOR_DEVICE_ATTR_2(in11_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 11, 1);
+static SENSOR_DEVICE_ATTR_2(in12_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 12, 1);
+static SENSOR_DEVICE_ATTR_2(in13_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 13, 1);
+static SENSOR_DEVICE_ATTR_2(in14_min, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 14, 1);
+
+static SENSOR_DEVICE_ATTR_2(in0_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 0, 2);
+static SENSOR_DEVICE_ATTR_2(in1_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 1, 2);
+static SENSOR_DEVICE_ATTR_2(in2_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 2, 2);
+static SENSOR_DEVICE_ATTR_2(in3_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 3, 2);
+static SENSOR_DEVICE_ATTR_2(in4_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 4, 2);
+static SENSOR_DEVICE_ATTR_2(in5_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 5, 2);
+static SENSOR_DEVICE_ATTR_2(in6_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 6, 2);
+static SENSOR_DEVICE_ATTR_2(in7_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 7, 2);
+static SENSOR_DEVICE_ATTR_2(in8_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 8, 2);
+static SENSOR_DEVICE_ATTR_2(in9_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 9, 2);
+static SENSOR_DEVICE_ATTR_2(in10_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 10, 2);
+static SENSOR_DEVICE_ATTR_2(in11_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 11, 2);
+static SENSOR_DEVICE_ATTR_2(in12_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 12, 2);
+static SENSOR_DEVICE_ATTR_2(in13_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 13, 2);
+static SENSOR_DEVICE_ATTR_2(in14_max, S_IWUSR | S_IRUGO, show_in_reg,
+			    store_in_reg, 14, 2);
+
+static struct attribute *nct6775_attributes_in[15][5] = {
+	{
+		&sensor_dev_attr_in0_input.dev_attr.attr,
+		&sensor_dev_attr_in0_min.dev_attr.attr,
+		&sensor_dev_attr_in0_max.dev_attr.attr,
+		&sensor_dev_attr_in0_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in1_input.dev_attr.attr,
+		&sensor_dev_attr_in1_min.dev_attr.attr,
+		&sensor_dev_attr_in1_max.dev_attr.attr,
+		&sensor_dev_attr_in1_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in2_input.dev_attr.attr,
+		&sensor_dev_attr_in2_min.dev_attr.attr,
+		&sensor_dev_attr_in2_max.dev_attr.attr,
+		&sensor_dev_attr_in2_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in3_input.dev_attr.attr,
+		&sensor_dev_attr_in3_min.dev_attr.attr,
+		&sensor_dev_attr_in3_max.dev_attr.attr,
+		&sensor_dev_attr_in3_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in4_input.dev_attr.attr,
+		&sensor_dev_attr_in4_min.dev_attr.attr,
+		&sensor_dev_attr_in4_max.dev_attr.attr,
+		&sensor_dev_attr_in4_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in5_input.dev_attr.attr,
+		&sensor_dev_attr_in5_min.dev_attr.attr,
+		&sensor_dev_attr_in5_max.dev_attr.attr,
+		&sensor_dev_attr_in5_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in6_input.dev_attr.attr,
+		&sensor_dev_attr_in6_min.dev_attr.attr,
+		&sensor_dev_attr_in6_max.dev_attr.attr,
+		&sensor_dev_attr_in6_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in7_input.dev_attr.attr,
+		&sensor_dev_attr_in7_min.dev_attr.attr,
+		&sensor_dev_attr_in7_max.dev_attr.attr,
+		&sensor_dev_attr_in7_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in8_input.dev_attr.attr,
+		&sensor_dev_attr_in8_min.dev_attr.attr,
+		&sensor_dev_attr_in8_max.dev_attr.attr,
+		&sensor_dev_attr_in8_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in9_input.dev_attr.attr,
+		&sensor_dev_attr_in9_min.dev_attr.attr,
+		&sensor_dev_attr_in9_max.dev_attr.attr,
+		&sensor_dev_attr_in9_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in10_input.dev_attr.attr,
+		&sensor_dev_attr_in10_min.dev_attr.attr,
+		&sensor_dev_attr_in10_max.dev_attr.attr,
+		&sensor_dev_attr_in10_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in11_input.dev_attr.attr,
+		&sensor_dev_attr_in11_min.dev_attr.attr,
+		&sensor_dev_attr_in11_max.dev_attr.attr,
+		&sensor_dev_attr_in11_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in12_input.dev_attr.attr,
+		&sensor_dev_attr_in12_min.dev_attr.attr,
+		&sensor_dev_attr_in12_max.dev_attr.attr,
+		&sensor_dev_attr_in12_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in13_input.dev_attr.attr,
+		&sensor_dev_attr_in13_min.dev_attr.attr,
+		&sensor_dev_attr_in13_max.dev_attr.attr,
+		&sensor_dev_attr_in13_alarm.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_in14_input.dev_attr.attr,
+		&sensor_dev_attr_in14_min.dev_attr.attr,
+		&sensor_dev_attr_in14_max.dev_attr.attr,
+		&sensor_dev_attr_in14_alarm.dev_attr.attr,
+		NULL
+	},
+};
+
+static const struct attribute_group nct6775_group_in[15] = {
+	{ .attrs = nct6775_attributes_in[0] },
+	{ .attrs = nct6775_attributes_in[1] },
+	{ .attrs = nct6775_attributes_in[2] },
+	{ .attrs = nct6775_attributes_in[3] },
+	{ .attrs = nct6775_attributes_in[4] },
+	{ .attrs = nct6775_attributes_in[5] },
+	{ .attrs = nct6775_attributes_in[6] },
+	{ .attrs = nct6775_attributes_in[7] },
+	{ .attrs = nct6775_attributes_in[8] },
+	{ .attrs = nct6775_attributes_in[9] },
+	{ .attrs = nct6775_attributes_in[10] },
+	{ .attrs = nct6775_attributes_in[11] },
+	{ .attrs = nct6775_attributes_in[12] },
+	{ .attrs = nct6775_attributes_in[13] },
+	{ .attrs = nct6775_attributes_in[14] },
+};
+
+static ssize_t
+show_name(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct nct6775_data *data = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", data->name);
+}
+
+static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
+
+static ssize_t
+show_vid(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct nct6775_data *data = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
+}
+
+static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
+
+/*
+ * Driver and device management
+ */
+
+static void nct6775_device_remove_files(struct device *dev)
+{
+	/*
+	 * some entries in the following arrays may not have been used in
+	 * device_create_file(), but device_remove_file() will ignore them
+	 */
+	int i;
+	struct nct6775_data *data = dev_get_drvdata(dev);
+
+	for (i = 0; i < data->in_num; i++)
+		sysfs_remove_group(&dev->kobj, &nct6775_group_in[i]);
+
+	device_remove_file(dev, &dev_attr_name);
+	device_remove_file(dev, &dev_attr_cpu0_vid);
+}
+
+/* Get the monitoring functions started */
+static inline void nct6775_init_device(struct nct6775_data *data)
+{
+	u8 tmp;
+
+	/* Start monitoring if needed */
+	if (data->REG_CONFIG) {
+		tmp = nct6775_read_value(data, data->REG_CONFIG);
+		if (!(tmp & 0x01))
+			nct6775_write_value(data, data->REG_CONFIG, tmp | 0x01);
+	}
+
+	/* Enable VBAT monitoring if needed */
+	tmp = nct6775_read_value(data, data->REG_VBAT);
+	if (!(tmp & 0x01))
+		nct6775_write_value(data, data->REG_VBAT, tmp | 0x01);
+}
+
+static int nct6775_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct nct6775_sio_data *sio_data = dev->platform_data;
+	struct nct6775_data *data;
+	struct resource *res;
+	int i, err = 0;
+
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (!devm_request_region(&pdev->dev, res->start, IOREGION_LENGTH,
+				 DRVNAME))
+		return -EBUSY;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(struct nct6775_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->kind = sio_data->kind;
+	data->addr = res->start;
+	mutex_init(&data->lock);
+	mutex_init(&data->update_lock);
+	data->name = nct6775_device_names[data->kind];
+	data->bank = 0xff;		/* Force initial bank selection */
+	platform_set_drvdata(pdev, data);
+
+	switch (data->kind) {
+	case nct6775:
+		data->in_num = 9;
+
+		data->ALARM_BITS = NCT6775_ALARM_BITS;
+
+		data->REG_CONFIG = NCT6775_REG_CONFIG;
+		data->REG_VBAT = NCT6775_REG_VBAT;
+		data->REG_VIN = NCT6775_REG_IN;
+		data->REG_IN_MINMAX[0] = NCT6775_REG_IN_MIN;
+		data->REG_IN_MINMAX[1] = NCT6775_REG_IN_MAX;
+		data->REG_ALARM = NCT6775_REG_ALARM;
+		break;
+	case nct6776:
+		data->in_num = 9;
+
+		data->ALARM_BITS = NCT6776_ALARM_BITS;
+
+		data->REG_CONFIG = NCT6775_REG_CONFIG;
+		data->REG_VBAT = NCT6775_REG_VBAT;
+		data->REG_VIN = NCT6775_REG_IN;
+		data->REG_IN_MINMAX[0] = NCT6775_REG_IN_MIN;
+		data->REG_IN_MINMAX[1] = NCT6775_REG_IN_MAX;
+		data->REG_ALARM = NCT6775_REG_ALARM;
+		break;
+	case nct6779:
+		data->in_num = 15;
+
+		data->ALARM_BITS = NCT6779_ALARM_BITS;
+
+		data->REG_CONFIG = NCT6775_REG_CONFIG;
+		data->REG_VBAT = NCT6775_REG_VBAT;
+		data->REG_VIN = NCT6779_REG_IN;
+		data->REG_IN_MINMAX[0] = NCT6775_REG_IN_MIN;
+		data->REG_IN_MINMAX[1] = NCT6775_REG_IN_MAX;
+		data->REG_ALARM = NCT6779_REG_ALARM;
+		break;
+	default:
+		return -ENODEV;
+	}
+	data->have_in = (1 << data->in_num) - 1;
+
+	/* Initialize the chip */
+	nct6775_init_device(data);
+
+	data->vrm = vid_which_vrm();
+	err = superio_enter(sio_data->sioreg);
+	if (err)
+		return err;
+
+	/*
+	 * Read VID value
+	 * We can get the VID input values directly at logical device D 0xe3.
+	 */
+	superio_select(sio_data->sioreg, NCT6775_LD_VID);
+	data->vid = superio_inb(sio_data->sioreg, 0xe3);
+	superio_exit(sio_data->sioreg);
+
+	err = device_create_file(dev, &dev_attr_cpu0_vid);
+	if (err)
+		return err;
+
+	for (i = 0; i < data->in_num; i++) {
+		if (!(data->have_in & (1 << i)))
+			continue;
+		err = sysfs_create_group(&dev->kobj, &nct6775_group_in[i]);
+		if (err)
+			goto exit_remove;
+	}
+
+	err = device_create_file(dev, &dev_attr_name);
+	if (err)
+		goto exit_remove;
+
+	data->hwmon_dev = hwmon_device_register(dev);
+	if (IS_ERR(data->hwmon_dev)) {
+		err = PTR_ERR(data->hwmon_dev);
+		goto exit_remove;
+	}
+
+	return 0;
+
+exit_remove:
+	nct6775_device_remove_files(dev);
+	return err;
+}
+
+static int nct6775_remove(struct platform_device *pdev)
+{
+	struct nct6775_data *data = platform_get_drvdata(pdev);
+
+	hwmon_device_unregister(data->hwmon_dev);
+	nct6775_device_remove_files(&pdev->dev);
+
+	return 0;
+}
+
+static struct platform_driver nct6775_driver = {
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= DRVNAME,
+	},
+	.probe		= nct6775_probe,
+	.remove		= nct6775_remove,
+};
+
+/* nct6775_find() looks for a '627 in the Super-I/O config space */
+static int __init nct6775_find(int sioaddr, unsigned short *addr,
+			       struct nct6775_sio_data *sio_data)
+{
+	static const char sio_name_NCT6775[] __initconst = "NCT6775F";
+	static const char sio_name_NCT6776[] __initconst = "NCT6776F";
+	static const char sio_name_NCT6779[] __initconst = "NCT6779D";
+
+	u16 val;
+	const char *sio_name;
+	int err;
+
+	err = superio_enter(sioaddr);
+	if (err)
+		return err;
+
+	if (force_id)
+		val = force_id;
+	else
+		val = (superio_inb(sioaddr, SIO_REG_DEVID) << 8)
+		    | superio_inb(sioaddr, SIO_REG_DEVID + 1);
+	switch (val & SIO_ID_MASK) {
+	case SIO_NCT6775_ID:
+		sio_data->kind = nct6775;
+		sio_name = sio_name_NCT6775;
+		break;
+	case SIO_NCT6776_ID:
+		sio_data->kind = nct6776;
+		sio_name = sio_name_NCT6776;
+		break;
+	case SIO_NCT6779_ID:
+		sio_data->kind = nct6779;
+		sio_name = sio_name_NCT6779;
+		break;
+	default:
+		if (val != 0xffff)
+			pr_debug("unsupported chip ID: 0x%04x\n", val);
+		superio_exit(sioaddr);
+		return -ENODEV;
+	}
+
+	/* We have a known chip, find the HWM I/O address */
+	superio_select(sioaddr, NCT6775_LD_HWM);
+	val = (superio_inb(sioaddr, SIO_REG_ADDR) << 8)
+	    | superio_inb(sioaddr, SIO_REG_ADDR + 1);
+	*addr = val & IOREGION_ALIGNMENT;
+	if (*addr == 0) {
+		pr_err("Refusing to enable a Super-I/O device with a base I/O port 0\n");
+		superio_exit(sioaddr);
+		return -ENODEV;
+	}
+
+	/* Activate logical device if needed */
+	val = superio_inb(sioaddr, SIO_REG_ENABLE);
+	if (!(val & 0x01)) {
+		pr_warn("Forcibly enabling Super-I/O. Sensor is probably unusable.\n");
+		superio_outb(sioaddr, SIO_REG_ENABLE, val | 0x01);
+	}
+
+	superio_exit(sioaddr);
+	pr_info("Found %s chip at %#x\n", sio_name, *addr);
+	sio_data->sioreg = sioaddr;
+
+	return 0;
+}
+
+/*
+ * when Super-I/O functions move to a separate file, the Super-I/O
+ * bus will manage the lifetime of the device and this module will only keep
+ * track of the nct6775 driver. But since we platform_device_alloc(), we
+ * must keep track of the device
+ */
+static struct platform_device *pdev;
+
+static int __init sensors_nct6775_init(void)
+{
+	int err;
+	unsigned short address;
+	struct resource res;
+	struct nct6775_sio_data sio_data;
+
+	/*
+	 * initialize sio_data->kind and sio_data->sioreg.
+	 *
+	 * when Super-I/O functions move to a separate file, the Super-I/O
+	 * driver will probe 0x2e and 0x4e and auto-detect the presence of a
+	 * nct6775 hardware monitor, and call probe()
+	 */
+	if (nct6775_find(0x2e, &address, &sio_data) &&
+	    nct6775_find(0x4e, &address, &sio_data))
+		return -ENODEV;
+
+	err = platform_driver_register(&nct6775_driver);
+	if (err)
+		goto exit;
+
+	pdev = platform_device_alloc(DRVNAME, address);
+	if (!pdev) {
+		err = -ENOMEM;
+		pr_err("Device allocation failed\n");
+		goto exit_unregister;
+	}
+
+	err = platform_device_add_data(pdev, &sio_data,
+				       sizeof(struct nct6775_sio_data));
+	if (err) {
+		pr_err("Platform data allocation failed\n");
+		goto exit_device_put;
+	}
+
+	memset(&res, 0, sizeof(res));
+	res.name = DRVNAME;
+	res.start = address + IOREGION_OFFSET;
+	res.end = address + IOREGION_OFFSET + IOREGION_LENGTH - 1;
+	res.flags = IORESOURCE_IO;
+
+	err = acpi_check_resource_conflict(&res);
+	if (err)
+		goto exit_device_put;
+
+	err = platform_device_add_resources(pdev, &res, 1);
+	if (err) {
+		pr_err("Device resource addition failed (%d)\n", err);
+		goto exit_device_put;
+	}
+
+	/* platform_device_add calls probe() */
+	err = platform_device_add(pdev);
+	if (err) {
+		pr_err("Device addition failed (%d)\n", err);
+		goto exit_device_put;
+	}
+
+	return 0;
+
+exit_device_put:
+	platform_device_put(pdev);
+exit_unregister:
+	platform_driver_unregister(&nct6775_driver);
+exit:
+	return err;
+}
+
+static void __exit sensors_nct6775_exit(void)
+{
+	platform_device_unregister(pdev);
+	platform_driver_unregister(&nct6775_driver);
+}
+
+MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
+MODULE_DESCRIPTION("NCT6775F/NCT6776F/NCT6779D driver");
+MODULE_LICENSE("GPL");
+
+module_init(sensors_nct6775_init);
+module_exit(sensors_nct6775_exit);