--- /dev/null
+/*
+ * IBM PowerNV platform sensors for temperature/fan/voltage/power
+ * Copyright (C) 2014 IBM
+ *
+ * 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.
+ */
+
+#define DRVNAME "ibmpowernv"
+#define pr_fmt(fmt) DRVNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+#include <linux/platform_device.h>
+#include <asm/opal.h>
+#include <linux/err.h>
+
+#define MAX_ATTR_LEN 32
+
+/* Sensor suffix name from DT */
+#define DT_FAULT_ATTR_SUFFIX "faulted"
+#define DT_DATA_ATTR_SUFFIX "data"
+#define DT_THRESHOLD_ATTR_SUFFIX "thrs"
+
+/*
+ * Enumerates all the types of sensors in the POWERNV platform and does index
+ * into 'struct sensor_group'
+ */
+enum sensors {
+ FAN,
+ AMBIENT_TEMP,
+ POWER_SUPPLY,
+ POWER_INPUT,
+ MAX_SENSOR_TYPE,
+};
+
+static struct sensor_group {
+ const char *name;
+ const char *compatible;
+ struct attribute_group group;
+ u32 attr_count;
+} sensor_groups[] = {
+ {"fan", "ibm,opal-sensor-cooling-fan"},
+ {"temp", "ibm,opal-sensor-amb-temp"},
+ {"in", "ibm,opal-sensor-power-supply"},
+ {"power", "ibm,opal-sensor-power"}
+};
+
+struct sensor_data {
+ u32 id; /* An opaque id of the firmware for each sensor */
+ enum sensors type;
+ char name[MAX_ATTR_LEN];
+ struct device_attribute dev_attr;
+};
+
+struct platform_data {
+ const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
+ u32 sensors_count; /* Total count of sensors from each group */
+};
+
+/* Platform device representing all the ibmpowernv sensors */
+static struct platform_device *pdevice;
+
+static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct sensor_data *sdata = container_of(devattr, struct sensor_data,
+ dev_attr);
+ ssize_t ret;
+ u32 x;
+
+ ret = opal_get_sensor_data(sdata->id, &x);
+ if (ret)
+ return ret;
+
+ /* Convert temperature to milli-degrees */
+ if (sdata->type == AMBIENT_TEMP)
+ x *= 1000;
+ /* Convert power to micro-watts */
+ else if (sdata->type == POWER_INPUT)
+ x *= 1000000;
+
+ return sprintf(buf, "%u\n", x);
+}
+
+static int __init get_sensor_index_attr(const char *name, u32 *index,
+ char *attr)
+{
+ char *hash_pos = strchr(name, '#');
+ char buf[8] = { 0 };
+ char *dash_pos;
+ u32 copy_len;
+ int err;
+
+ if (!hash_pos)
+ return -EINVAL;
+
+ dash_pos = strchr(hash_pos, '-');
+ if (!dash_pos)
+ return -EINVAL;
+
+ copy_len = dash_pos - hash_pos - 1;
+ if (copy_len >= sizeof(buf))
+ return -EINVAL;
+
+ strncpy(buf, hash_pos + 1, copy_len);
+
+ err = kstrtou32(buf, 10, index);
+ if (err)
+ return err;
+
+ strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
+
+ return 0;
+}
+
+/*
+ * This function translates the DT node name into the 'hwmon' attribute name.
+ * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
+ * which need to be mapped as fan2_input, temp1_max respectively before
+ * populating them inside hwmon device class.
+ */
+static int __init create_hwmon_attr_name(struct device *dev, enum sensors type,
+ const char *node_name,
+ char *hwmon_attr_name)
+{
+ char attr_suffix[MAX_ATTR_LEN];
+ char *attr_name;
+ u32 index;
+ int err;
+
+ err = get_sensor_index_attr(node_name, &index, attr_suffix);
+ if (err) {
+ dev_err(dev, "Sensor device node name '%s' is invalid\n",
+ node_name);
+ return err;
+ }
+
+ if (!strcmp(attr_suffix, DT_FAULT_ATTR_SUFFIX)) {
+ attr_name = "fault";
+ } else if (!strcmp(attr_suffix, DT_DATA_ATTR_SUFFIX)) {
+ attr_name = "input";
+ } else if (!strcmp(attr_suffix, DT_THRESHOLD_ATTR_SUFFIX)) {
+ if (type == AMBIENT_TEMP)
+ attr_name = "max";
+ else if (type == FAN)
+ attr_name = "min";
+ else
+ return -ENOENT;
+ } else {
+ return -ENOENT;
+ }
+
+ snprintf(hwmon_attr_name, MAX_ATTR_LEN, "%s%d_%s",
+ sensor_groups[type].name, index, attr_name);
+ return 0;
+}
+
+static int __init populate_attr_groups(struct platform_device *pdev)
+{
+ struct platform_data *pdata = platform_get_drvdata(pdev);
+ const struct attribute_group **pgroups = pdata->attr_groups;
+ struct device_node *opal, *np;
+ enum sensors type;
+
+ opal = of_find_node_by_path("/ibm,opal/sensors");
+ if (!opal) {
+ dev_err(&pdev->dev, "Opal node 'sensors' not found\n");
+ return -ENODEV;
+ }
+
+ for_each_child_of_node(opal, np) {
+ if (np->name == NULL)
+ continue;
+
+ for (type = 0; type < MAX_SENSOR_TYPE; type++)
+ if (of_device_is_compatible(np,
+ sensor_groups[type].compatible)) {
+ sensor_groups[type].attr_count++;
+ break;
+ }
+ }
+
+ of_node_put(opal);
+
+ for (type = 0; type < MAX_SENSOR_TYPE; type++) {
+ sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
+ sizeof(struct attribute *) *
+ (sensor_groups[type].attr_count + 1),
+ GFP_KERNEL);
+ if (!sensor_groups[type].group.attrs)
+ return -ENOMEM;
+
+ pgroups[type] = &sensor_groups[type].group;
+ pdata->sensors_count += sensor_groups[type].attr_count;
+ sensor_groups[type].attr_count = 0;
+ }
+
+ return 0;
+}
+
+/*
+ * Iterate through the device tree for each child of 'sensors' node, create
+ * a sysfs attribute file, the file is named by translating the DT node name
+ * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
+ * etc..
+ */
+static int __init create_device_attrs(struct platform_device *pdev)
+{
+ struct platform_data *pdata = platform_get_drvdata(pdev);
+ const struct attribute_group **pgroups = pdata->attr_groups;
+ struct device_node *opal, *np;
+ struct sensor_data *sdata;
+ const __be32 *sensor_id;
+ enum sensors type;
+ u32 count = 0;
+ int err = 0;
+
+ opal = of_find_node_by_path("/ibm,opal/sensors");
+ sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
+ GFP_KERNEL);
+ if (!sdata) {
+ err = -ENOMEM;
+ goto exit_put_node;
+ }
+
+ for_each_child_of_node(opal, np) {
+ if (np->name == NULL)
+ continue;
+
+ for (type = 0; type < MAX_SENSOR_TYPE; type++)
+ if (of_device_is_compatible(np,
+ sensor_groups[type].compatible))
+ break;
+
+ if (type == MAX_SENSOR_TYPE)
+ continue;
+
+ sensor_id = of_get_property(np, "sensor-id", NULL);
+ if (!sensor_id) {
+ dev_info(&pdev->dev,
+ "'sensor-id' missing in the node '%s'\n",
+ np->name);
+ continue;
+ }
+
+ sdata[count].id = be32_to_cpup(sensor_id);
+ sdata[count].type = type;
+ err = create_hwmon_attr_name(&pdev->dev, type, np->name,
+ sdata[count].name);
+ if (err)
+ goto exit_put_node;
+
+ sysfs_attr_init(&sdata[count].dev_attr.attr);
+ sdata[count].dev_attr.attr.name = sdata[count].name;
+ sdata[count].dev_attr.attr.mode = S_IRUGO;
+ sdata[count].dev_attr.show = show_sensor;
+
+ pgroups[type]->attrs[sensor_groups[type].attr_count++] =
+ &sdata[count++].dev_attr.attr;
+ }
+
+exit_put_node:
+ of_node_put(opal);
+ return err;
+}
+
+static int __init ibmpowernv_probe(struct platform_device *pdev)
+{
+ struct platform_data *pdata;
+ struct device *hwmon_dev;
+ int err;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, pdata);
+ pdata->sensors_count = 0;
+ err = populate_attr_groups(pdev);
+ if (err)
+ return err;
+
+ /* Create sysfs attribute data for each sensor found in the DT */
+ err = create_device_attrs(pdev);
+ if (err)
+ return err;
+
+ /* Finally, register with hwmon */
+ hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
+ pdata,
+ pdata->attr_groups);
+
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct platform_driver ibmpowernv_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = DRVNAME,
+ },
+};
+
+static int __init ibmpowernv_init(void)
+{
+ int err;
+
+ pdevice = platform_device_alloc(DRVNAME, 0);
+ if (!pdevice) {
+ pr_err("Device allocation failed\n");
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ err = platform_device_add(pdevice);
+ if (err) {
+ pr_err("Device addition failed (%d)\n", err);
+ goto exit_device_put;
+ }
+
+ err = platform_driver_probe(&ibmpowernv_driver, ibmpowernv_probe);
+ if (err) {
+ pr_err("Platfrom driver probe failed\n");
+ goto exit_device_del;
+ }
+
+ return 0;
+
+exit_device_del:
+ platform_device_del(pdevice);
+exit_device_put:
+ platform_device_put(pdevice);
+exit:
+ return err;
+}
+
+static void __exit ibmpowernv_exit(void)
+{
+ platform_driver_unregister(&ibmpowernv_driver);
+ platform_device_unregister(pdevice);
+}
+
+MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("IBM POWERNV platform sensors");
+MODULE_LICENSE("GPL");
+
+module_init(ibmpowernv_init);
+module_exit(ibmpowernv_exit);
projects / deliverable / linux.git / commitdiff
