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 000000000000..fe2c2616c6b1
--- /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);