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Message-ID: <20070828164905.GM32667@tree.beaverton.ibm.com>
Date:	Tue, 28 Aug 2007 09:49:06 -0700
From:	"Darrick J. Wong" <djwong@...ibm.com>
To:	Jean Delvare <khali@...ux-fr.org>
Cc:	Henrique de Moraes Holschuh <hmh@....eng.br>,
	"Mark M. Hoffman" <mhoffman@...htlink.com>,
	linux-kernel@...r.kernel.org, lm-sensors@...sensors.org
Subject: [PATCH] v2 of IBM power meter driver

ibm_pex: Driver to export IBM PowerExecutive power meter sensor readings
in mW.

Signed-off-by: Darrick J. Wong <djwong@...ibm.com>
---

 drivers/hwmon/Kconfig  |   12 +
 drivers/hwmon/Makefile |    1 
 drivers/hwmon/ibmpex.c |  600 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 613 insertions(+), 0 deletions(-)

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 555f470..41ffa2e 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -275,6 +275,18 @@ config SENSORS_CORETEMP
 	  sensor inside your CPU. Supported all are all known variants
 	  of Intel Core family.
 
+config SENSORS_IBMPEX
+	tristate "IBM PowerExecutive temperature/power sensors"
+	depends on IPMI_SI
+	help
+	  If you say yes here you get support for the temperature and
+	  power sensors in various IBM System X servers that support
+	  PowerExecutive.  So far this includes the x3550, x3650, x3655,
+	  x3755, and certain HS20 blades.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called ibmpex.
+
 config SENSORS_IT87
 	tristate "ITE IT87xx and compatibles"
 	select HWMON_VID
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index a133981..31da6fe 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_SENSORS_FSCPOS)	+= fscpos.o
 obj-$(CONFIG_SENSORS_GL518SM)	+= gl518sm.o
 obj-$(CONFIG_SENSORS_GL520SM)	+= gl520sm.o
 obj-$(CONFIG_SENSORS_HDAPS)	+= hdaps.o
+obj-$(CONFIG_SENSORS_IBMPEX)	+= ibmpex.o
 obj-$(CONFIG_SENSORS_IT87)	+= it87.o
 obj-$(CONFIG_SENSORS_K8TEMP)	+= k8temp.o
 obj-$(CONFIG_SENSORS_LM63)	+= lm63.o
diff --git a/drivers/hwmon/ibmpex.c b/drivers/hwmon/ibmpex.c
new file mode 100644
index 0000000..10f1205
--- /dev/null
+++ b/drivers/hwmon/ibmpex.c
@@ -0,0 +1,600 @@
+/*
+ * A hwmon driver for the IBM PowerExecutive temperature/power sensors
+ * Copyright (C) 2007 IBM
+ *
+ * Author: Darrick J. Wong <djwong@...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/mutex.h>
+
+#define REFRESH_INTERVAL	(5 * HZ)
+#define DRVNAME			"ibmpex"
+
+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			value;
+	s16			max;
+	s16			min;
+	int			multiplier;
+
+	struct sensor_device_attribute	attr_value;
+	struct sensor_device_attribute	attr_max;
+	struct sensor_device_attribute	attr_min;
+};
+
+struct ibmpex_bmc_data {
+	struct list_head	list;
+	struct class_device	*class_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] = 0x1;
+	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,
+	       data->rx_msg_data[3] | ((u16)data->rx_msg_data[2] << 8),
+	       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] = 0x2;
+	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] = 0x3;
+	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] = 0x6;
+	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 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].value = ((u16)data->rx_msg_data[16] << 8) |
+					 data->rx_msg_data[17];
+		data->sensors[i].min = ((u16)data->rx_msg_data[18] << 8) |
+				       data->rx_msg_data[19];
+		data->sensors[i].max = ((u16)data->rx_msg_data[20] << 8) |
+				       data->rx_msg_data[21];
+	}
+
+	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 *attr = to_sensor_dev_attr(devattr);
+	int iface = attr->index >> 8;
+	int sensor = attr->index & 0xFF;
+	struct ibmpex_bmc_data *data = get_bmc_data(iface);
+	int multiplier = data->sensors[sensor].multiplier;
+	ibmpex_update_device(data);
+
+	return sprintf(buf, "%d\n", data->sensors[sensor].value * multiplier);
+}
+
+static ssize_t ibmpex_show_max(struct device *dev,
+				  struct device_attribute *devattr,
+				  char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	int iface = attr->index >> 8;
+	int sensor = attr->index & 0xFF;
+	struct ibmpex_bmc_data *data = get_bmc_data(iface);
+	int multiplier = data->sensors[sensor].multiplier;
+	ibmpex_update_device(data);
+
+	return sprintf(buf, "%d\n", data->sensors[sensor].max * multiplier);
+}
+
+static ssize_t ibmpex_show_min(struct device *dev,
+				  struct device_attribute *devattr,
+				  char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	int iface = attr->index >> 8;
+	int sensor = attr->index & 0xFF;
+	struct ibmpex_bmc_data *data = get_bmc_data(iface);
+	int multiplier = data->sensors[sensor].multiplier;
+	ibmpex_update_device(data);
+
+	return sprintf(buf, "%d\n", data->sensors[sensor].min * multiplier);
+}
+
+static int is_power_sensor(const char *sensor_id, int len)
+{
+	if (len < 3)
+		return 0;
+
+	if (sensor_id[0] == 0x70 &&
+	    sensor_id[1] == 0x77 &&
+	    sensor_id[2] == 0x72)
+		return 1;
+	return 0;
+}
+
+static int is_temp_sensor(const char *sensor_id, int len)
+{
+	if (len < 3)
+		return 0;
+
+	if (sensor_id[0] == 0x74 &&
+	    sensor_id[1] == 0x65 &&
+	    sensor_id[2] == 0x6D)
+		return 1;
+	return 0;
+}
+
+static int power_sensor_multiplier(const char *sensor_id, int len)
+{
+	int i;
+
+	for (i = 3; i < len - 1; i++)
+		if (sensor_id[i] == 0x41 &&
+		    sensor_id[i + 1] == 0x43)
+			return 1000;
+
+	return 100;
+}
+
+static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
+{
+	int i, err;
+	char *n, *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";
+			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";
+			num_temp++;
+			sensor_counter = num_temp;
+			data->sensors[i].multiplier = 1;
+		} else
+			continue;
+
+		data->sensors[i].in_use = 1;
+
+		/* Create value attribute */
+		n = kmalloc(32, GFP_KERNEL);
+		if (!n)
+			goto exit_remove;
+		sprintf(n, "%s%d_input", sensor_type, sensor_counter);
+		data->sensors[i].attr_value.dev_attr.attr.name = n;
+		data->sensors[i].attr_value.dev_attr.attr.mode = S_IRUGO;
+		data->sensors[i].attr_value.dev_attr.show = ibmpex_show_sensor;
+		data->sensors[i].attr_value.index = (data->interface << 8) |
+						    (i & 0xFF);
+
+		err = device_create_file(data->bmc_device,
+					 &data->sensors[i].attr_value.dev_attr);
+		if (err) {
+			data->sensors[i].attr_value.dev_attr.attr.name = NULL;
+			kfree(n);
+			goto exit_remove;
+		}
+
+		/* Create max attribute */
+		n = kmalloc(32, GFP_KERNEL);
+		if (!n)
+			goto exit_remove;
+		sprintf(n, "%s%d_max_input", sensor_type, sensor_counter);
+		data->sensors[i].attr_max.dev_attr.attr.name = n;
+		data->sensors[i].attr_max.dev_attr.attr.mode = S_IRUGO;
+		data->sensors[i].attr_max.dev_attr.show = ibmpex_show_max;
+		data->sensors[i].attr_max.index = (data->interface << 8) |
+						    (i & 0xFF);
+
+		err = device_create_file(data->bmc_device,
+					 &data->sensors[i].attr_max.dev_attr);
+		if (err) {
+			data->sensors[i].attr_max.dev_attr.attr.name = NULL;
+			kfree(n);
+			goto exit_remove;
+		}
+
+		/* Create min attribute */
+		n = kmalloc(32, GFP_KERNEL);
+		if (!n)
+			goto exit_remove;
+		sprintf(n, "%s%d_min_input", sensor_type, sensor_counter);
+		data->sensors[i].attr_min.dev_attr.attr.name = n;
+		data->sensors[i].attr_min.dev_attr.attr.mode = S_IRUGO;
+		data->sensors[i].attr_min.dev_attr.show = ibmpex_show_min;
+		data->sensors[i].attr_min.index = (data->interface << 8) |
+						    (i & 0xFF);
+
+		err = device_create_file(data->bmc_device,
+					 &data->sensors[i].attr_min.dev_attr);
+		if (err) {
+			data->sensors[i].attr_min.dev_attr.attr.name = NULL;
+			kfree(n);
+			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:
+	for (i = 0; i < data->num_sensors; i++) {
+		if (data->sensors[i].attr_value.dev_attr.attr.name)
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr_value.dev_attr);
+		kfree(data->sensors[i].attr_value.dev_attr.attr.name);
+		if (data->sensors[i].attr_max.dev_attr.attr.name)
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr_max.dev_attr);
+		kfree(data->sensors[i].attr_max.dev_attr.attr.name);
+		if (data->sensors[i].attr_min.dev_attr.attr.name)
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr_min.dev_attr);
+		kfree(data->sensors[i].attr_min.dev_attr.attr.name);
+	}
+
+	kfree(data->sensors);
+	return -ENOENT;
+}
+
+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 = 0x3A;
+	data->tx_message.cmd = 0x3C;
+	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->class_dev = hwmon_device_register(data->bmc_device);
+
+	if (IS_ERR(data->class_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 */
+	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->class_dev);
+out_user:
+	ipmi_destroy_user(data->user);
+out:
+	kfree(data);
+}
+
+static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
+{
+	int i;
+
+	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
+	for (i = 0; i < data->num_sensors; i++) {
+		if (data->sensors[i].attr_max.dev_attr.attr.name)
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr_max.dev_attr);
+		kfree(data->sensors[i].attr_max.dev_attr.attr.name);
+		if (data->sensors[i].attr_min.dev_attr.attr.name)
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr_min.dev_attr);
+		kfree(data->sensors[i].attr_min.dev_attr.attr.name);
+		if (data->sensors[i].attr_value.dev_attr.attr.name)
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr_value.dev_attr);
+		kfree(data->sensors[i].attr_value.dev_attr.attr.name);
+	}
+	list_del(&data->list);
+	hwmon_device_unregister(data->class_dev);
+	ipmi_destroy_user(data->user);
+	if (data->sensors)
+		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@...ibm.com>");
+MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
+MODULE_LICENSE("GPL");
+
+module_init(ibmpex_init);
+module_exit(ibmpex_exit);

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