igb: Enable hwmon data output for thermal sensors via I2C.

Some of our adapters have internal sensors that report thermal data.  This
patch enables reporting of that data via sysfs.

Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/igb/igb_hwmon.c b/drivers/net/ethernet/intel/igb/igb_hwmon.c
new file mode 100644
index 0000000..106bd7c
--- /dev/null
+++ b/drivers/net/ethernet/intel/igb/igb_hwmon.c
@@ -0,0 +1,242 @@
+/*******************************************************************************
+
+  Intel(R) Gigabit Ethernet Linux driver
+  Copyright(c) 2007-2012 Intel Corporation.
+
+  This program is free software; you can redistribute it and/or modify it
+  under the terms and conditions of the GNU General Public License,
+  version 2, as published by the Free Software Foundation.
+
+  This program is distributed in the hope 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.,
+  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+
+  The full GNU General Public License is included in this distribution in
+  the file called "COPYING".
+
+  Contact Information:
+  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
+  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+
+*******************************************************************************/
+
+#include "igb.h"
+#include "e1000_82575.h"
+#include "e1000_hw.h"
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/sysfs.h>
+#include <linux/kobject.h>
+#include <linux/device.h>
+#include <linux/netdevice.h>
+#include <linux/hwmon.h>
+#include <linux/pci.h>
+
+#ifdef CONFIG_IGB_HWMON
+/* hwmon callback functions */
+static ssize_t igb_hwmon_show_location(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	struct hwmon_attr *igb_attr = container_of(attr, struct hwmon_attr,
+						     dev_attr);
+	return sprintf(buf, "loc%u\n",
+		       igb_attr->sensor->location);
+}
+
+static ssize_t igb_hwmon_show_temp(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct hwmon_attr *igb_attr = container_of(attr, struct hwmon_attr,
+						     dev_attr);
+	unsigned int value;
+
+	/* reset the temp field */
+	igb_attr->hw->mac.ops.get_thermal_sensor_data(igb_attr->hw);
+
+	value = igb_attr->sensor->temp;
+
+	/* display millidegree */
+	value *= 1000;
+
+	return sprintf(buf, "%u\n", value);
+}
+
+static ssize_t igb_hwmon_show_cautionthresh(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct hwmon_attr *igb_attr = container_of(attr, struct hwmon_attr,
+						     dev_attr);
+	unsigned int value = igb_attr->sensor->caution_thresh;
+
+	/* display millidegree */
+	value *= 1000;
+
+	return sprintf(buf, "%u\n", value);
+}
+
+static ssize_t igb_hwmon_show_maxopthresh(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct hwmon_attr *igb_attr = container_of(attr, struct hwmon_attr,
+						     dev_attr);
+	unsigned int value = igb_attr->sensor->max_op_thresh;
+
+	/* display millidegree */
+	value *= 1000;
+
+	return sprintf(buf, "%u\n", value);
+}
+
+/* igb_add_hwmon_attr - Create hwmon attr table for a hwmon sysfs file.
+ * @ adapter: pointer to the adapter structure
+ * @ offset: offset in the eeprom sensor data table
+ * @ type: type of sensor data to display
+ *
+ * For each file we want in hwmon's sysfs interface we need a device_attribute
+ * This is included in our hwmon_attr struct that contains the references to
+ * the data structures we need to get the data to display.
+ */
+static int igb_add_hwmon_attr(struct igb_adapter *adapter,
+				unsigned int offset, int type) {
+	int rc;
+	unsigned int n_attr;
+	struct hwmon_attr *igb_attr;
+
+	n_attr = adapter->igb_hwmon_buff.n_hwmon;
+	igb_attr = &adapter->igb_hwmon_buff.hwmon_list[n_attr];
+
+	switch (type) {
+	case IGB_HWMON_TYPE_LOC:
+		igb_attr->dev_attr.show = igb_hwmon_show_location;
+		snprintf(igb_attr->name, sizeof(igb_attr->name),
+			 "temp%u_label", offset);
+		break;
+	case IGB_HWMON_TYPE_TEMP:
+		igb_attr->dev_attr.show = igb_hwmon_show_temp;
+		snprintf(igb_attr->name, sizeof(igb_attr->name),
+			 "temp%u_input", offset);
+		break;
+	case IGB_HWMON_TYPE_CAUTION:
+		igb_attr->dev_attr.show = igb_hwmon_show_cautionthresh;
+		snprintf(igb_attr->name, sizeof(igb_attr->name),
+			 "temp%u_max", offset);
+		break;
+	case IGB_HWMON_TYPE_MAX:
+		igb_attr->dev_attr.show = igb_hwmon_show_maxopthresh;
+		snprintf(igb_attr->name, sizeof(igb_attr->name),
+			 "temp%u_crit", offset);
+		break;
+	default:
+		rc = -EPERM;
+		return rc;
+	}
+
+	/* These always the same regardless of type */
+	igb_attr->sensor =
+		&adapter->hw.mac.thermal_sensor_data.sensor[offset];
+	igb_attr->hw = &adapter->hw;
+	igb_attr->dev_attr.store = NULL;
+	igb_attr->dev_attr.attr.mode = S_IRUGO;
+	igb_attr->dev_attr.attr.name = igb_attr->name;
+	sysfs_attr_init(&igb_attr->dev_attr.attr);
+	rc = device_create_file(&adapter->pdev->dev,
+				&igb_attr->dev_attr);
+	if (rc == 0)
+		++adapter->igb_hwmon_buff.n_hwmon;
+
+	return rc;
+}
+
+static void igb_sysfs_del_adapter(struct igb_adapter *adapter)
+{
+	int i;
+
+	if (adapter == NULL)
+		return;
+
+	for (i = 0; i < adapter->igb_hwmon_buff.n_hwmon; i++) {
+		device_remove_file(&adapter->pdev->dev,
+			   &adapter->igb_hwmon_buff.hwmon_list[i].dev_attr);
+	}
+
+	kfree(adapter->igb_hwmon_buff.hwmon_list);
+
+	if (adapter->igb_hwmon_buff.device)
+		hwmon_device_unregister(adapter->igb_hwmon_buff.device);
+}
+
+/* called from igb_main.c */
+void igb_sysfs_exit(struct igb_adapter *adapter)
+{
+	igb_sysfs_del_adapter(adapter);
+}
+
+/* called from igb_main.c */
+int igb_sysfs_init(struct igb_adapter *adapter)
+{
+	struct hwmon_buff *igb_hwmon = &adapter->igb_hwmon_buff;
+	unsigned int i;
+	int n_attrs;
+	int rc = 0;
+
+	/* If this method isn't defined we don't support thermals */
+	if (adapter->hw.mac.ops.init_thermal_sensor_thresh == NULL)
+		goto exit;
+
+	/* Don't create thermal hwmon interface if no sensors present */
+	rc = (adapter->hw.mac.ops.init_thermal_sensor_thresh(&adapter->hw));
+		if (rc)
+			goto exit;
+
+	/* Allocation space for max attributes
+	 * max num sensors * values (loc, temp, max, caution)
+	 */
+	n_attrs = E1000_MAX_SENSORS * 4;
+	igb_hwmon->hwmon_list = kcalloc(n_attrs, sizeof(struct hwmon_attr),
+					  GFP_KERNEL);
+	if (!igb_hwmon->hwmon_list) {
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	igb_hwmon->device = hwmon_device_register(&adapter->pdev->dev);
+	if (IS_ERR(igb_hwmon->device)) {
+		rc = PTR_ERR(igb_hwmon->device);
+		goto err;
+	}
+
+	for (i = 0; i < E1000_MAX_SENSORS; i++) {
+
+		/* Only create hwmon sysfs entries for sensors that have
+		 * meaningful data.
+		 */
+		if (adapter->hw.mac.thermal_sensor_data.sensor[i].location == 0)
+			continue;
+
+		/* Bail if any hwmon attr struct fails to initialize */
+		rc = igb_add_hwmon_attr(adapter, i, IGB_HWMON_TYPE_CAUTION);
+		rc |= igb_add_hwmon_attr(adapter, i, IGB_HWMON_TYPE_LOC);
+		rc |= igb_add_hwmon_attr(adapter, i, IGB_HWMON_TYPE_TEMP);
+		rc |= igb_add_hwmon_attr(adapter, i, IGB_HWMON_TYPE_MAX);
+		if (rc)
+			goto err;
+	}
+
+	goto exit;
+
+err:
+	igb_sysfs_del_adapter(adapter);
+exit:
+	return rc;
+}
+#endif