1 files changed, 489 insertions, 0 deletions

diff --git a/kernel/drivers/hwmon/ibmpowernv.c b/kernel/drivers/hwmon/ibmpowernv.c
new file mode 100644
index 000000000..4255514b2
--- /dev/null
+++ b/kernel/drivers/hwmon/ibmpowernv.c
@@ -0,0 +1,489 @@
+/*
+ * 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>
+#include <asm/cputhreads.h>
+#include <asm/smp.h>
+
+#define MAX_ATTR_LEN	32
+#define MAX_LABEL_LEN	64
+
+/* 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,
+	TEMP,
+	POWER_SUPPLY,
+	POWER_INPUT,
+	MAX_SENSOR_TYPE,
+};
+
+#define INVALID_INDEX (-1U)
+
+static struct sensor_group {
+	const char *name;
+	const char *compatible;
+	struct attribute_group group;
+	u32 attr_count;
+	u32 hwmon_index;
+} 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 */
+	u32 hwmon_index;
+	u32 opal_index;
+	enum sensors type;
+	char label[MAX_LABEL_LEN];
+	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 */
+};
+
+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 == TEMP)
+		x *= 1000;
+	/* Convert power to micro-watts */
+	else if (sdata->type == POWER_INPUT)
+		x *= 1000000;
+
+	return sprintf(buf, "%u\n", x);
+}
+
+static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
+			  char *buf)
+{
+	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
+						 dev_attr);
+
+	return sprintf(buf, "%s\n", sdata->label);
+}
+
+static int __init get_logical_cpu(int hwcpu)
+{
+	int cpu;
+
+	for_each_possible_cpu(cpu)
+		if (get_hard_smp_processor_id(cpu) == hwcpu)
+			return cpu;
+
+	return -ENOENT;
+}
+
+static void __init make_sensor_label(struct device_node *np,
+				     struct sensor_data *sdata,
+				     const char *label)
+{
+	u32 id;
+	size_t n;
+
+	n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
+
+	/*
+	 * Core temp pretty print
+	 */
+	if (!of_property_read_u32(np, "ibm,pir", &id)) {
+		int cpuid = get_logical_cpu(id);
+
+		if (cpuid >= 0)
+			/*
+			 * The digital thermal sensors are associated
+			 * with a core. Let's print out the range of
+			 * cpu ids corresponding to the hardware
+			 * threads of the core.
+			 */
+			n += snprintf(sdata->label + n,
+				      sizeof(sdata->label) - n, " %d-%d",
+				      cpuid, cpuid + threads_per_core - 1);
+		else
+			n += snprintf(sdata->label + n,
+				      sizeof(sdata->label) - n, " phy%d", id);
+	}
+
+	/*
+	 * Membuffer pretty print
+	 */
+	if (!of_property_read_u32(np, "ibm,chip-id", &id))
+		n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
+			      " %d", id & 0xffff);
+}
+
+static int 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;
+}
+
+static const char *convert_opal_attr_name(enum sensors type,
+					  const char *opal_attr)
+{
+	const char *attr_name = NULL;
+
+	if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
+		attr_name = "fault";
+	} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
+		attr_name = "input";
+	} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
+		if (type == TEMP)
+			attr_name = "max";
+		else if (type == FAN)
+			attr_name = "min";
+	}
+
+	return attr_name;
+}
+
+/*
+ * 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 const char *parse_opal_node_name(const char *node_name,
+					enum sensors type, u32 *index)
+{
+	char attr_suffix[MAX_ATTR_LEN];
+	const char *attr_name;
+	int err;
+
+	err = get_sensor_index_attr(node_name, index, attr_suffix);
+	if (err)
+		return ERR_PTR(err);
+
+	attr_name = convert_opal_attr_name(type, attr_suffix);
+	if (!attr_name)
+		return ERR_PTR(-ENOENT);
+
+	return attr_name;
+}
+
+static int get_sensor_type(struct device_node *np)
+{
+	enum sensors type;
+	const char *str;
+
+	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
+		if (of_device_is_compatible(np, sensor_groups[type].compatible))
+			return type;
+	}
+
+	/*
+	 * Let's check if we have a newer device tree
+	 */
+	if (!of_device_is_compatible(np, "ibm,opal-sensor"))
+		return MAX_SENSOR_TYPE;
+
+	if (of_property_read_string(np, "sensor-type", &str))
+		return MAX_SENSOR_TYPE;
+
+	for (type = 0; type < MAX_SENSOR_TYPE; type++)
+		if (!strcmp(str, sensor_groups[type].name))
+			return type;
+
+	return MAX_SENSOR_TYPE;
+}
+
+static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
+				  struct sensor_data *sdata_table, int count)
+{
+	int i;
+
+	/*
+	 * We don't use the OPAL index on newer device trees
+	 */
+	if (sdata->opal_index != INVALID_INDEX) {
+		for (i = 0; i < count; i++)
+			if (sdata_table[i].opal_index == sdata->opal_index &&
+			    sdata_table[i].type == sdata->type)
+				return sdata_table[i].hwmon_index;
+	}
+	return ++sensor_groups[sdata->type].hwmon_index;
+}
+
+static int 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");
+	for_each_child_of_node(opal, np) {
+		const char *label;
+
+		if (np->name == NULL)
+			continue;
+
+		type = get_sensor_type(np);
+		if (type == MAX_SENSOR_TYPE)
+			continue;
+
+		sensor_groups[type].attr_count++;
+
+		/*
+		 * add a new attribute for labels
+		 */
+		if (!of_property_read_string(np, "label", &label))
+			sensor_groups[type].attr_count++;
+	}
+
+	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;
+}
+
+static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
+			      ssize_t (*show)(struct device *dev,
+					      struct device_attribute *attr,
+					      char *buf))
+{
+	snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
+		 sensor_groups[sdata->type].name, sdata->hwmon_index,
+		 attr_name);
+
+	sysfs_attr_init(&sdata->dev_attr.attr);
+	sdata->dev_attr.attr.name = sdata->name;
+	sdata->dev_attr.attr.mode = S_IRUGO;
+	sdata->dev_attr.show = show;
+}
+
+/*
+ * 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 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;
+	u32 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) {
+		const char *attr_name;
+		u32 opal_index;
+		const char *label;
+
+		if (np->name == NULL)
+			continue;
+
+		type = get_sensor_type(np);
+		if (type == MAX_SENSOR_TYPE)
+			continue;
+
+		/*
+		 * Newer device trees use a "sensor-data" property
+		 * name for input.
+		 */
+		if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
+		    of_property_read_u32(np, "sensor-data", &sensor_id)) {
+			dev_info(&pdev->dev,
+				 "'sensor-id' missing in the node '%s'\n",
+				 np->name);
+			continue;
+		}
+
+		sdata[count].id = sensor_id;
+		sdata[count].type = type;
+
+		/*
+		 * If we can not parse the node name, it means we are
+		 * running on a newer device tree. We can just forget
+		 * about the OPAL index and use a defaut value for the
+		 * hwmon attribute name
+		 */
+		attr_name = parse_opal_node_name(np->name, type, &opal_index);
+		if (IS_ERR(attr_name)) {
+			attr_name = "input";
+			opal_index = INVALID_INDEX;
+		}
+
+		sdata[count].opal_index = opal_index;
+		sdata[count].hwmon_index =
+			get_sensor_hwmon_index(&sdata[count], sdata, count);
+
+		create_hwmon_attr(&sdata[count], attr_name, show_sensor);
+
+		pgroups[type]->attrs[sensor_groups[type].attr_count++] =
+				&sdata[count++].dev_attr.attr;
+
+		if (!of_property_read_string(np, "label", &label)) {
+			/*
+			 * For the label attribute, we can reuse the
+			 * "properties" of the previous "input"
+			 * attribute. They are related to the same
+			 * sensor.
+			 */
+			sdata[count].type = type;
+			sdata[count].opal_index = sdata[count - 1].opal_index;
+			sdata[count].hwmon_index = sdata[count - 1].hwmon_index;
+
+			make_sensor_label(np, &sdata[count], label);
+
+			create_hwmon_attr(&sdata[count], "label", show_label);
+
+			pgroups[type]->attrs[sensor_groups[type].attr_count++] =
+				&sdata[count++].dev_attr.attr;
+		}
+	}
+
+exit_put_node:
+	of_node_put(opal);
+	return err;
+}
+
+static int 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 const struct platform_device_id opal_sensor_driver_ids[] = {
+	{
+		.name = "opal-sensor",
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
+
+static struct platform_driver ibmpowernv_driver = {
+	.probe		= ibmpowernv_probe,
+	.id_table	= opal_sensor_driver_ids,
+	.driver		= {
+		.name	= DRVNAME,
+	},
+};
+
+module_platform_driver(ibmpowernv_driver);
+
+MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("IBM POWERNV platform sensors");
+MODULE_LICENSE("GPL");