hwmon: IBM power meter driver

Add a driver to export IBM PowerExecutive power meter sensors.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>

1 files changed, 608 insertions, 0 deletions

diff --git a/drivers/hwmon/ibmpex.c b/drivers/hwmon/ibmpex.c
new file mode 100644
index 0000000..fe2c261
--- /dev/null
+++ b/drivers/hwmon/ibmpex.c
@@ -0,0 +1,608 @@
+/*
+ * A hwmon driver for the IBM PowerExecutive temperature/power sensors
+ * Copyright (C) 2007 IBM
+ *
+ * Author: Darrick J. Wong <djwong@us.ibm.com>
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/ipmi.h>
+#include <linux/module.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+
+#define REFRESH_INTERVAL	(2 * HZ)
+#define DRVNAME			"ibmpex"
+
+#define PEX_GET_VERSION		1
+#define PEX_GET_SENSOR_COUNT	2
+#define PEX_GET_SENSOR_NAME	3
+#define PEX_RESET_HIGH_LOW	4
+#define PEX_GET_SENSOR_DATA	6
+
+#define PEX_NET_FUNCTION	0x3A
+#define PEX_COMMAND		0x3C
+
+static inline u16 extract_value(const char *data, int offset)
+{
+	return be16_to_cpup((u16 *)&data[offset]);
+}
+
+#define TEMP_SENSOR		1
+#define POWER_SENSOR		2
+
+#define PEX_SENSOR_TYPE_LEN	3
+static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
+static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
+
+#define PEX_MULT_LEN		2
+static u8 const watt_sensor_sig[]  = {0x41, 0x43};
+
+#define PEX_NUM_SENSOR_FUNCS	3
+static char const * const power_sensor_name_templates[] = {
+	"%s%d_average",
+	"%s%d_average_lowest",
+	"%s%d_average_highest"
+};
+static char const * const temp_sensor_name_templates[] = {
+	"%s%d_input",
+	"%s%d_input_lowest",
+	"%s%d_input_highest"
+};
+
+static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
+static void ibmpex_register_bmc(int iface, struct device *dev);
+static void ibmpex_bmc_gone(int iface);
+
+struct ibmpex_sensor_data {
+	int			in_use;
+	s16			values[PEX_NUM_SENSOR_FUNCS];
+	int			multiplier;
+
+	struct sensor_device_attribute_2	attr[PEX_NUM_SENSOR_FUNCS];
+};
+
+struct ibmpex_bmc_data {
+	struct list_head	list;
+	struct device		*hwmon_dev;
+	struct device		*bmc_device;
+	struct mutex		lock;
+	char			valid;
+	unsigned long		last_updated;	/* In jiffies */
+
+	struct ipmi_addr	address;
+	struct completion	read_complete;
+	ipmi_user_t		user;
+	int			interface;
+
+	struct kernel_ipmi_msg	tx_message;
+	unsigned char		tx_msg_data[IPMI_MAX_MSG_LENGTH];
+	long			tx_msgid;
+
+	unsigned char		rx_msg_data[IPMI_MAX_MSG_LENGTH];
+	unsigned long		rx_msg_len;
+	unsigned char		rx_result;
+	int			rx_recv_type;
+
+	unsigned char		sensor_major;
+	unsigned char		sensor_minor;
+
+	unsigned char		num_sensors;
+	struct ibmpex_sensor_data	*sensors;
+};
+
+struct ibmpex_driver_data {
+	struct list_head	bmc_data;
+	struct ipmi_smi_watcher	bmc_events;
+	struct ipmi_user_hndl	ipmi_hndlrs;
+};
+
+static struct ibmpex_driver_data driver_data = {
+	.bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
+	.bmc_events = {
+		.owner = THIS_MODULE,
+		.new_smi = ibmpex_register_bmc,
+		.smi_gone = ibmpex_bmc_gone,
+	},
+	.ipmi_hndlrs = {
+		.ipmi_recv_hndl = ibmpex_msg_handler,
+	},
+};
+
+static int ibmpex_send_message(struct ibmpex_bmc_data *data)
+{
+	int err;
+
+	err = ipmi_validate_addr(&data->address, sizeof(data->address));
+	if (err)
+		goto out;
+
+	data->tx_msgid++;
+	err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
+				   &data->tx_message, data, 0, 0, 0);
+	if (err)
+		goto out1;
+
+	return 0;
+out1:
+	printk(KERN_ERR "%s: request_settime=%x\n", __FUNCTION__, err);
+	return err;
+out:
+	printk(KERN_ERR "%s: validate_addr=%x\n", __FUNCTION__, err);
+	return err;
+}
+
+static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
+{
+	data->tx_msg_data[0] = PEX_GET_VERSION;
+	data->tx_message.data_len = 1;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len != 6)
+		return -ENOENT;
+
+	data->sensor_major = data->rx_msg_data[0];
+	data->sensor_minor = data->rx_msg_data[1];
+
+	printk(KERN_INFO DRVNAME ": Found BMC with sensor interface "
+	       "v%d.%d %d-%02d-%02d on interface %d\n",
+	       data->sensor_major,
+	       data->sensor_minor,
+	       extract_value(data->rx_msg_data, 2),
+	       data->rx_msg_data[4],
+	       data->rx_msg_data[5],
+	       data->interface);
+
+	return 0;
+}
+
+static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
+{
+	data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
+	data->tx_message.data_len = 1;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len != 1)
+		return -ENOENT;
+
+	return data->rx_msg_data[0];
+}
+
+static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
+{
+	data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
+	data->tx_msg_data[1] = sensor;
+	data->tx_message.data_len = 2;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len < 1)
+		return -ENOENT;
+
+	return 0;
+}
+
+static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
+{
+	data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
+	data->tx_msg_data[1] = sensor;
+	data->tx_message.data_len = 2;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len < 26) {
+		printk(KERN_ERR "Error reading sensor %d, please check.\n",
+		       sensor);
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
+{
+	data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
+	data->tx_message.data_len = 1;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	return 0;
+}
+
+static void ibmpex_update_device(struct ibmpex_bmc_data *data)
+{
+	int i, err;
+
+	mutex_lock(&data->lock);
+	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
+	    data->valid)
+		goto out;
+
+	for (i = 0; i < data->num_sensors; i++) {
+		if (!data->sensors[i].in_use)
+			continue;
+		err = ibmpex_query_sensor_data(data, i);
+		if (err)
+			continue;
+		data->sensors[i].values[0] =
+			extract_value(data->rx_msg_data, 16);
+		data->sensors[i].values[1] =
+			extract_value(data->rx_msg_data, 18);
+		data->sensors[i].values[2] =
+			extract_value(data->rx_msg_data, 20);
+	}
+
+	data->last_updated = jiffies;
+	data->valid = 1;
+
+out:
+	mutex_unlock(&data->lock);
+}
+
+static struct ibmpex_bmc_data *get_bmc_data(int iface)
+{
+	struct ibmpex_bmc_data *p, *next;
+
+	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
+		if (p->interface == iface)
+			return p;
+
+	return NULL;
+}
+
+static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
+			 char *buf)
+{
+	return sprintf(buf, "%s\n", DRVNAME);
+}
+static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);
+
+static ssize_t ibmpex_show_sensor(struct device *dev,
+				  struct device_attribute *devattr,
+				  char *buf)
+{
+	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
+	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
+	int mult = data->sensors[attr->index].multiplier;
+	ibmpex_update_device(data);
+
+	return sprintf(buf, "%d\n",
+		       data->sensors[attr->index].values[attr->nr] * mult);
+}
+
+static ssize_t ibmpex_reset_high_low(struct device *dev,
+				     struct device_attribute *devattr,
+				     const char *buf,
+				     size_t count)
+{
+	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
+
+	ibmpex_reset_high_low_data(data);
+
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(reset_high_low, S_IWUSR, NULL,
+			  ibmpex_reset_high_low, 0);
+
+static int is_power_sensor(const char *sensor_id, int len)
+{
+	if (len < PEX_SENSOR_TYPE_LEN)
+		return 0;
+
+	if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
+		return 1;
+	return 0;
+}
+
+static int is_temp_sensor(const char *sensor_id, int len)
+{
+	if (len < PEX_SENSOR_TYPE_LEN)
+		return 0;
+
+	if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
+		return 1;
+	return 0;
+}
+
+static int power_sensor_multiplier(const char *sensor_id, int len)
+{
+	int i;
+
+	for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
+		if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
+			return 1000000;
+
+	return 100000;
+}
+
+static int create_sensor(struct ibmpex_bmc_data *data, int type,
+			 int counter, int sensor, int func)
+{
+	int err;
+	char *n;
+
+	n = kmalloc(32, GFP_KERNEL);
+	if (!n)
+		return -ENOMEM;
+
+	if (type == TEMP_SENSOR)
+		sprintf(n, temp_sensor_name_templates[func], "temp", counter);
+	else if (type == POWER_SENSOR)
+		sprintf(n, power_sensor_name_templates[func], "power", counter);
+
+	data->sensors[sensor].attr[func].dev_attr.attr.name = n;
+	data->sensors[sensor].attr[func].dev_attr.attr.mode = S_IRUGO;
+	data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
+	data->sensors[sensor].attr[func].index = sensor;
+	data->sensors[sensor].attr[func].nr = func;
+
+	err = device_create_file(data->bmc_device,
+				 &data->sensors[sensor].attr[func].dev_attr);
+	if (err) {
+		data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
+		kfree(n);
+		return err;
+	}
+
+	return 0;
+}
+
+static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
+{
+	int i, j, err;
+	int sensor_type;
+	int sensor_counter;
+	int num_power = 0;
+	int num_temp = 0;
+
+	err = ibmpex_query_sensor_count(data);
+	if (err <= 0)
+		return -ENOENT;
+	data->num_sensors = err;
+
+	data->sensors = kzalloc(data->num_sensors * sizeof(*data->sensors),
+				GFP_KERNEL);
+	if (!data->sensors)
+		return -ENOMEM;
+
+	for (i = 0; i < data->num_sensors; i++) {
+		err = ibmpex_query_sensor_name(data, i);
+		if (err)
+			continue;
+
+		if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
+			sensor_type = POWER_SENSOR;
+			num_power++;
+			sensor_counter = num_power;
+			data->sensors[i].multiplier =
+				power_sensor_multiplier(data->rx_msg_data,
+						     data->rx_msg_len);
+		} else if (is_temp_sensor(data->rx_msg_data,
+					  data->rx_msg_len)) {
+			sensor_type = TEMP_SENSOR;
+			num_temp++;
+			sensor_counter = num_temp;
+			data->sensors[i].multiplier = 1;
+		} else
+			continue;
+
+		data->sensors[i].in_use = 1;
+
+		/* Create attributes */
+		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
+			err = create_sensor(data, sensor_type, sensor_counter,
+					    i, j);
+			if (err)
+				goto exit_remove;
+		}
+	}
+
+	err = device_create_file(data->bmc_device,
+			&sensor_dev_attr_reset_high_low.dev_attr);
+	if (err)
+		goto exit_remove;
+
+	err = device_create_file(data->bmc_device,
+			&sensor_dev_attr_name.dev_attr);
+	if (err)
+		goto exit_remove;
+
+	return 0;
+
+exit_remove:
+	device_remove_file(data->bmc_device,
+			   &sensor_dev_attr_reset_high_low.dev_attr);
+	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
+	for (i = 0; i < data->num_sensors; i++)
+		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
+			if (!data->sensors[i].attr[j].dev_attr.attr.name)
+				continue;
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr[j].dev_attr);
+			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
+		}
+
+	kfree(data->sensors);
+	return err;
+}
+
+static void ibmpex_register_bmc(int iface, struct device *dev)
+{
+	struct ibmpex_bmc_data *data;
+	int err;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		printk(KERN_ERR DRVNAME ": Insufficient memory for BMC "
+		       "interface %d.\n", data->interface);
+		return;
+	}
+
+	data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	data->address.channel = IPMI_BMC_CHANNEL;
+	data->address.data[0] = 0;
+	data->interface = iface;
+	data->bmc_device = dev;
+
+	/* Create IPMI messaging interface user */
+	err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
+			       data, &data->user);
+	if (err < 0) {
+		printk(KERN_ERR DRVNAME ": Error, unable to register user with "
+		       "ipmi interface %d\n",
+		       data->interface);
+		goto out;
+	}
+
+	mutex_init(&data->lock);
+
+	/* Initialize message */
+	data->tx_msgid = 0;
+	init_completion(&data->read_complete);
+	data->tx_message.netfn = PEX_NET_FUNCTION;
+	data->tx_message.cmd = PEX_COMMAND;
+	data->tx_message.data = data->tx_msg_data;
+
+	/* Does this BMC support PowerExecutive? */
+	err = ibmpex_ver_check(data);
+	if (err)
+		goto out_user;
+
+	/* Register the BMC as a HWMON class device */
+	data->hwmon_dev = hwmon_device_register(data->bmc_device);
+
+	if (IS_ERR(data->hwmon_dev)) {
+		printk(KERN_ERR DRVNAME ": Error, unable to register hwmon "
+		       "class device for interface %d\n",
+		       data->interface);
+		kfree(data);
+		return;
+	}
+
+	/* finally add the new bmc data to the bmc data list */
+	dev_set_drvdata(dev, data);
+	list_add_tail(&data->list, &driver_data.bmc_data);
+
+	/* Now go find all the sensors */
+	err = ibmpex_find_sensors(data);
+	if (err) {
+		printk(KERN_ERR "Error %d allocating memory\n", err);
+		goto out_register;
+	}
+
+	return;
+
+out_register:
+	hwmon_device_unregister(data->hwmon_dev);
+out_user:
+	ipmi_destroy_user(data->user);
+out:
+	kfree(data);
+}
+
+static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
+{
+	int i, j;
+
+	device_remove_file(data->bmc_device,
+			   &sensor_dev_attr_reset_high_low.dev_attr);
+	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
+	for (i = 0; i < data->num_sensors; i++)
+		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
+			if (!data->sensors[i].attr[j].dev_attr.attr.name)
+				continue;
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr[j].dev_attr);
+			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
+		}
+
+	list_del(&data->list);
+	dev_set_drvdata(data->bmc_device, NULL);
+	hwmon_device_unregister(data->hwmon_dev);
+	ipmi_destroy_user(data->user);
+	kfree(data->sensors);
+	kfree(data);
+}
+
+static void ibmpex_bmc_gone(int iface)
+{
+	struct ibmpex_bmc_data *data = get_bmc_data(iface);
+
+	if (!data)
+		return;
+
+	ibmpex_bmc_delete(data);
+}
+
+static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
+{
+	struct ibmpex_bmc_data *data = (struct ibmpex_bmc_data *)user_msg_data;
+
+	if (msg->msgid != data->tx_msgid) {
+		printk(KERN_ERR "Received msgid (%02x) and transmitted "
+		       "msgid (%02x) mismatch!\n",
+		       (int)msg->msgid,
+		       (int)data->tx_msgid);
+		ipmi_free_recv_msg(msg);
+		return;
+	}
+
+	data->rx_recv_type = msg->recv_type;
+	if (msg->msg.data_len > 0)
+		data->rx_result = msg->msg.data[0];
+	else
+		data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
+
+	if (msg->msg.data_len > 1) {
+		data->rx_msg_len = msg->msg.data_len - 1;
+		memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
+	} else
+		data->rx_msg_len = 0;
+
+	ipmi_free_recv_msg(msg);
+	complete(&data->read_complete);
+}
+
+static int __init ibmpex_init(void)
+{
+	return ipmi_smi_watcher_register(&driver_data.bmc_events);
+}
+
+static void __exit ibmpex_exit(void)
+{
+	struct ibmpex_bmc_data *p, *next;
+
+	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
+	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
+		ibmpex_bmc_delete(p);
+}
+
+MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
+MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
+MODULE_LICENSE("GPL");
+
+module_init(ibmpex_init);
+module_exit(ibmpex_exit);