hwmon: Add driver for Texas Instruments TMP421/422/423 sensor chips
authorAndre Prendel <andre.prendel@gmx.de>
Tue, 15 Sep 2009 15:18:11 +0000 (17:18 +0200)
committerJean Delvare <khali@linux-fr.org>
Tue, 15 Sep 2009 15:18:11 +0000 (17:18 +0200)
Add support for Texas Instruments TMP421/422/423 temperature sensor IC.

TI's TMP421/422/423 are I2C temperature sensor chips. These chips are
similar to TI's TMP401/411 chips, but with reduced functionality (only
temperature measurement). The chips have one local sensor and up to
three (TMP423) remote sensors.

Signed-off-by: Andre Prendel <andre.prendel@gmx.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
drivers/hwmon/Kconfig
drivers/hwmon/Makefile
drivers/hwmon/tmp421.c [new file with mode: 0644]

index 2e25b7a827d396d1357646066b711ad8550ea287..ee57a4a2cd72da18a4a34270542b6c3912458cce 100644 (file)
@@ -814,6 +814,16 @@ config SENSORS_TMP401
          This driver can also be built as a module.  If so, the module
          will be called tmp401.
 
+config SENSORS_TMP421
+       tristate "Texas Instruments TMP421 and compatible"
+       depends on I2C && EXPERIMENTAL
+       help
+         If you say yes here you get support for Texas Instruments TMP421,
+         TMP422 and TMP423 temperature sensor chips.
+
+         This driver can also be built as a module.  If so, the module
+         will be called tmp421.
+
 config SENSORS_VIA686A
        tristate "VIA686A"
        depends on PCI
index 7f239a247c336614f88f5ccaa77eb6d2ccc7cf33..b577b4997207b0054d666fa7fb39999803231dda 100644 (file)
@@ -84,6 +84,7 @@ obj-$(CONFIG_SENSORS_SMSC47M1)        += smsc47m1.o
 obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
 obj-$(CONFIG_SENSORS_THMC50)   += thmc50.o
 obj-$(CONFIG_SENSORS_TMP401)   += tmp401.o
+obj-$(CONFIG_SENSORS_TMP421)   += tmp421.o
 obj-$(CONFIG_SENSORS_VIA686A)  += via686a.o
 obj-$(CONFIG_SENSORS_VT1211)   += vt1211.o
 obj-$(CONFIG_SENSORS_VT8231)   += vt8231.o
diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
new file mode 100644 (file)
index 0000000..2092434
--- /dev/null
@@ -0,0 +1,347 @@
+/* tmp421.c
+ *
+ * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
+ * Preliminary support by:
+ * Melvin Rook, Raymond Ng
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/*
+ * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
+ * Supported models: TMP421, TMP422, TMP423
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/sysfs.h>
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
+                                      I2C_CLIENT_END };
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_3(tmp421, tmp422, tmp423);
+
+/* The TMP421 registers */
+#define TMP421_CONFIG_REG_1                    0x09
+#define TMP421_CONVERSION_RATE_REG             0x0B
+#define TMP421_MANUFACTURER_ID_REG             0xFE
+#define TMP421_DEVICE_ID_REG                   0xFF
+
+static const u8 TMP421_TEMP_MSB[4]             = { 0x00, 0x01, 0x02, 0x03 };
+static const u8 TMP421_TEMP_LSB[4]             = { 0x10, 0x11, 0x12, 0x13 };
+
+/* Flags */
+#define TMP421_CONFIG_SHUTDOWN                 0x40
+#define TMP421_CONFIG_RANGE                    0x04
+
+/* Manufacturer / Device ID's */
+#define TMP421_MANUFACTURER_ID                 0x55
+#define TMP421_DEVICE_ID                       0x21
+#define TMP422_DEVICE_ID                       0x22
+#define TMP423_DEVICE_ID                       0x23
+
+static const struct i2c_device_id tmp421_id[] = {
+       { "tmp421", tmp421 },
+       { "tmp422", tmp422 },
+       { "tmp423", tmp423 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, tmp421_id);
+
+struct tmp421_data {
+       struct device *hwmon_dev;
+       struct mutex update_lock;
+       char valid;
+       unsigned long last_updated;
+       int kind;
+       u8 config;
+       s16 temp[4];
+};
+
+static int temp_from_s16(s16 reg)
+{
+       int temp = reg;
+
+       return (temp * 1000 + 128) / 256;
+}
+
+static int temp_from_u16(u16 reg)
+{
+       int temp = reg;
+
+       /* Add offset for extended temperature range. */
+       temp -= 64 * 256;
+
+       return (temp * 1000 + 128) / 256;
+}
+
+static struct tmp421_data *tmp421_update_device(struct device *dev)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct tmp421_data *data = i2c_get_clientdata(client);
+       int i;
+
+       mutex_lock(&data->update_lock);
+
+       if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
+               data->config = i2c_smbus_read_byte_data(client,
+                       TMP421_CONFIG_REG_1);
+
+               for (i = 0; i <= data->kind; i++) {
+                       data->temp[i] = i2c_smbus_read_byte_data(client,
+                               TMP421_TEMP_MSB[i]) << 8;
+                       data->temp[i] |= i2c_smbus_read_byte_data(client,
+                               TMP421_TEMP_LSB[i]);
+               }
+               data->last_updated = jiffies;
+               data->valid = 1;
+       }
+
+       mutex_unlock(&data->update_lock);
+
+       return data;
+}
+
+static ssize_t show_temp_value(struct device *dev,
+                              struct device_attribute *devattr, char *buf)
+{
+       int index = to_sensor_dev_attr(devattr)->index;
+       struct tmp421_data *data = tmp421_update_device(dev);
+       int temp;
+
+       mutex_lock(&data->update_lock);
+       if (data->config & TMP421_CONFIG_RANGE)
+               temp = temp_from_u16(data->temp[index]);
+       else
+               temp = temp_from_s16(data->temp[index]);
+       mutex_unlock(&data->update_lock);
+
+       return sprintf(buf, "%d\n", temp);
+}
+
+static ssize_t show_fault(struct device *dev,
+                         struct device_attribute *devattr, char *buf)
+{
+       int index = to_sensor_dev_attr(devattr)->index;
+       struct tmp421_data *data = tmp421_update_device(dev);
+
+       /*
+        * The OPEN bit signals a fault. This is bit 0 of the temperature
+        * register (low byte).
+        */
+       if (data->temp[index] & 0x01)
+               return sprintf(buf, "1\n");
+       else
+               return sprintf(buf, "0\n");
+}
+
+static mode_t tmp421_is_visible(struct kobject *kobj, struct attribute *a,
+                               int n)
+{
+       struct device *dev = container_of(kobj, struct device, kobj);
+       struct tmp421_data *data = dev_get_drvdata(dev);
+       struct device_attribute *devattr;
+       unsigned int index;
+
+       devattr = container_of(a, struct device_attribute, attr);
+       index = to_sensor_dev_attr(devattr)->index;
+
+       if (data->kind > index)
+               return a->mode;
+
+       return 0;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_value, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_value, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp_value, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp_value, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
+
+static struct attribute *tmp421_attr[] = {
+       &sensor_dev_attr_temp1_input.dev_attr.attr,
+       &sensor_dev_attr_temp2_input.dev_attr.attr,
+       &sensor_dev_attr_temp2_fault.dev_attr.attr,
+       &sensor_dev_attr_temp3_input.dev_attr.attr,
+       &sensor_dev_attr_temp3_fault.dev_attr.attr,
+       &sensor_dev_attr_temp4_input.dev_attr.attr,
+       &sensor_dev_attr_temp4_fault.dev_attr.attr,
+       NULL
+};
+
+static const struct attribute_group tmp421_group = {
+       .attrs = tmp421_attr,
+       .is_visible = tmp421_is_visible,
+};
+
+static int tmp421_init_client(struct i2c_client *client)
+{
+       int config, config_orig;
+
+       /* Set the conversion rate to 2 Hz */
+       i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
+
+       /* Start conversions (disable shutdown if necessary) */
+       config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
+       if (config < 0) {
+               dev_err(&client->dev, "Could not read configuration"
+                        " register (%d)\n", config);
+               return -ENODEV;
+       }
+
+       config_orig = config;
+       config &= ~TMP421_CONFIG_SHUTDOWN;
+
+       if (config != config_orig) {
+               dev_info(&client->dev, "Enable monitoring chip\n");
+               i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
+       }
+
+       return 0;
+}
+
+static int tmp421_detect(struct i2c_client *client, int kind,
+                        struct i2c_board_info *info)
+{
+       struct i2c_adapter *adapter = client->adapter;
+       const char *names[] = { "TMP421", "TMP422", "TMP423" };
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+               return -ENODEV;
+
+       if (kind <= 0) {
+               u8 reg;
+
+               reg = i2c_smbus_read_byte_data(client,
+                                              TMP421_MANUFACTURER_ID_REG);
+               if (reg != TMP421_MANUFACTURER_ID)
+                       return -ENODEV;
+
+               reg = i2c_smbus_read_byte_data(client,
+                                              TMP421_DEVICE_ID_REG);
+               switch (reg) {
+               case TMP421_DEVICE_ID:
+                       kind = tmp421;
+                       break;
+               case TMP422_DEVICE_ID:
+                       kind = tmp422;
+                       break;
+               case TMP423_DEVICE_ID:
+                       kind = tmp423;
+                       break;
+               default:
+                       return -ENODEV;
+               }
+       }
+       strlcpy(info->type, tmp421_id[kind - 1].name, I2C_NAME_SIZE);
+       dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
+                names[kind - 1], client->addr);
+
+       return 0;
+}
+
+static int tmp421_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+       struct tmp421_data *data;
+       int err;
+
+       data = kzalloc(sizeof(struct tmp421_data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       i2c_set_clientdata(client, data);
+       mutex_init(&data->update_lock);
+       data->kind = id->driver_data;
+
+       err = tmp421_init_client(client);
+       if (err)
+               goto exit_free;
+
+       err = sysfs_create_group(&client->dev.kobj, &tmp421_group);
+       if (err)
+               goto exit_free;
+
+       data->hwmon_dev = hwmon_device_register(&client->dev);
+       if (IS_ERR(data->hwmon_dev)) {
+               err = PTR_ERR(data->hwmon_dev);
+               data->hwmon_dev = NULL;
+               goto exit_remove;
+       }
+       return 0;
+
+exit_remove:
+       sysfs_remove_group(&client->dev.kobj, &tmp421_group);
+
+exit_free:
+       i2c_set_clientdata(client, NULL);
+       kfree(data);
+
+       return err;
+}
+
+static int tmp421_remove(struct i2c_client *client)
+{
+       struct tmp421_data *data = i2c_get_clientdata(client);
+
+       hwmon_device_unregister(data->hwmon_dev);
+       sysfs_remove_group(&client->dev.kobj, &tmp421_group);
+
+       i2c_set_clientdata(client, NULL);
+       kfree(data);
+
+       return 0;
+}
+
+static struct i2c_driver tmp421_driver = {
+       .class = I2C_CLASS_HWMON,
+       .driver = {
+               .name   = "tmp421",
+       },
+       .probe = tmp421_probe,
+       .remove = tmp421_remove,
+       .id_table = tmp421_id,
+       .detect = tmp421_detect,
+       .address_data = &addr_data,
+};
+
+static int __init tmp421_init(void)
+{
+       return i2c_add_driver(&tmp421_driver);
+}
+
+static void __exit tmp421_exit(void)
+{
+       i2c_del_driver(&tmp421_driver);
+}
+
+MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
+MODULE_DESCRIPTION("Texas Instruments TMP421/422/423 temperature sensor"
+                  " driver");
+MODULE_LICENSE("GPL");
+
+module_init(tmp421_init);
+module_exit(tmp421_exit);