[PATCH v3 3/4] tsod: New hwmon driver for Temperature Sensors on DIMM

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
---
 drivers/hwmon/Kconfig  |  10 +++
 drivers/hwmon/Makefile |   1 +
 drivers/hwmon/tsod.c   | 195 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 206 insertions(+)
 create mode 100644 drivers/hwmon/tsod.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 89ac1cb..96edb87 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1462,6 +1462,16 @@ config SENSORS_MC13783_ADC
         help
           Support for the A/D converter on MC13783 and MC13892 PMIC.
 
+config SENSORS_TSOD
+	tristate "Temperature Sensor On DIMM (TSOD)"
+	depends on I2C
+	help
+	  If you say yes here you get support for the integrated temperature
+	  sensors on newer DIMMs that comply with JESD21-C.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called tsod.
+
 if ACPI
 
 comment "ACPI drivers"
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 8d6d97e..439ef1f 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -134,6 +134,7 @@ obj-$(CONFIG_SENSORS_W83L785TS)	+= w83l785ts.o
 obj-$(CONFIG_SENSORS_W83L786NG)	+= w83l786ng.o
 obj-$(CONFIG_SENSORS_WM831X)	+= wm831x-hwmon.o
 obj-$(CONFIG_SENSORS_WM8350)	+= wm8350-hwmon.o
+obj-$(CONFIG_SENSORS_TSOD)	+= tsod.o
 
 obj-$(CONFIG_PMBUS)		+= pmbus/
 
diff --git a/drivers/hwmon/tsod.c b/drivers/hwmon/tsod.c
new file mode 100644
index 0000000..f7bb070
--- /dev/null
+++ b/drivers/hwmon/tsod.c
@@ -0,0 +1,195 @@
+/*
+ * drivers/hwmon/tsod.c - Temperaure Sensor On DIMM
+ *
+ * Copyright (C) 2013 Andrew Lutomirski <luto@xxxxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License v2 as published by the
+ * Free Software Foundation.
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ *
+ * The official reference for these devices is JEDEC Standard No. 21-C,
+ * which is available for free from www.jedec.org.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/slab.h>
+
+/* Registers */
+#define TSOD_CURRENT_TEMP	5
+#define TSOD_VENDOR		6
+#define TSOD_DEVICE		7
+
+/*
+ * This driver does not program the trip points, etc. -- this is done by
+ * firmware, and the memory controller probably wants the defaults preserved.
+ */
+
+struct tsod_priv {
+	struct i2c_client *client;
+	struct device *hwmondev;
+};
+
+static ssize_t show_name(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "TSOD\n");
+}
+
+static ssize_t show_label(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "DIMM Temperature\n");
+}
+
+static ssize_t show_temperature(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct tsod_priv *priv = dev_get_drvdata(dev->parent);
+	int temp, raw;
+
+	raw = i2c_smbus_read_word_swapped(priv->client, TSOD_CURRENT_TEMP);
+	if (raw < 0)
+		return raw;
+
+	/*
+	 * The three high bits are undefined and the rest is twos-complement.
+	 * Use a sign-extending right shift to propagate the sign bit.
+	 */
+	temp = ((s16)((s16)raw << 3) >> 3);
+
+	/*
+	 * The value is in units of 0.0625 degrees, but we want it in
+	 * units of 0.001 degrees.
+	 */
+	return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(temp * 625, 10));
+}
+
+static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temperature, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL, 0);
+
+static struct attribute *tsod_hwmon_attributes[] = {
+	&dev_attr_name.attr,
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_label.dev_attr.attr,
+
+	NULL,
+};
+
+static const struct attribute_group tsod_hwmon_attr_group = {
+	.attrs	= tsod_hwmon_attributes,
+};
+
+static int tsod_detect(struct i2c_client *client, struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = client->adapter;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
+		return -ENODEV;
+
+	strlcpy(info->type, "tsod", I2C_NAME_SIZE);
+	return 0;
+}
+
+static int tsod_probe(struct i2c_client *client,
+		      const struct i2c_device_id *id)
+{
+	int ret;
+	struct tsod_priv *priv;
+
+	/* Sanity check the address */
+	if ((client->addr & 0x78) != 0x18)
+		return -ENODEV;
+
+	/* Sanity check: make sure we can read the temperature. */
+	ret = i2c_smbus_read_word_swapped(client, TSOD_CURRENT_TEMP);
+	if (ret < 0)
+		return -ENODEV;
+
+	priv = kzalloc(sizeof(struct tsod_priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->client = client;
+
+	priv->hwmondev = hwmon_device_register(&client->dev);
+	if (IS_ERR(priv->hwmondev)) {
+		ret = PTR_ERR(priv->hwmondev);
+		goto err_free;
+	}
+
+	i2c_set_clientdata(client, priv);
+
+	ret = sysfs_create_group(&priv->hwmondev->kobj, &tsod_hwmon_attr_group);
+	if (ret)
+		goto err_unreg;
+
+	return 0;
+
+err_unreg:
+	hwmon_device_unregister(&client->dev);
+
+err_free:
+	kfree(priv);
+	i2c_set_clientdata(client, 0);
+	return ret;
+}
+
+static int tsod_remove(struct i2c_client *client)
+{
+	struct tsod_priv *priv = i2c_get_clientdata(client);
+
+	sysfs_remove_group(&priv->hwmondev->kobj, &tsod_hwmon_attr_group);
+	hwmon_device_unregister(priv->hwmondev);
+	kfree(priv);
+	return 0;
+}
+
+static const unsigned short tsod_addresses[] = {
+	0x18, 0x19, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, I2C_CLIENT_END
+};
+
+static const struct i2c_device_id tsod_id[] = {
+	{ "tsod", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tsod_id);
+
+static struct i2c_driver tsod_driver = {
+	.driver = {
+		.name	= "tsod",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= tsod_probe,
+	.remove		= tsod_remove,
+	.id_table	= tsod_id,
+
+	/*
+	 * We do not claim I2C_CLASS_SPD -- there are other devices
+	 * on, e.g., the i2c_i801 bus that have these addresses.
+	 * Instead we let the dimm-bus code instantiate us.
+	 */
+
+	.detect		= tsod_detect,
+	.address_list	= tsod_addresses,
+};
+
+module_i2c_driver(tsod_driver);
+
+MODULE_AUTHOR("Andrew Lutomirski <luto@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Temperaure Sensor On DIMM");
+MODULE_LICENSE("GPL");
-- 
1.8.1.4


_______________________________________________
lm-sensors mailing list
lm-sensors@xxxxxxxxxxxxxx
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors




[Index of Archives]     [Linux Kernel]     [Linux Hardware Monitoring]     [Linux USB Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]

  Powered by Linux