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authorAlessandro Zummo <azummo-lists@towertech.it>2007-05-08 17:22:02 +0200
committerJean Delvare <khali@hyperion.delvare>2007-05-08 17:22:02 +0200
commit2d8dd65fc14287f2c004dd755e517ba0f45d446e (patch)
tree5f6a886a3dc2dcaf6a2fef59d0f6a83c76101e5c /drivers/hwmon/ad7418.c
parentd58ee056cc40117afe4d3bb03006ac537d779634 (diff)
hwmon: New AD7416, AD7417 and AD7418 driver
A driver for the Analog Devices AD7416, AD7417 and AD7418 chips. Signed-off-by: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/hwmon/ad7418.c')
-rw-r--r--drivers/hwmon/ad7418.c373
1 files changed, 373 insertions, 0 deletions
diff --git a/drivers/hwmon/ad7418.c b/drivers/hwmon/ad7418.c
new file mode 100644
index 000000000000..cc8b624a1e51
--- /dev/null
+++ b/drivers/hwmon/ad7418.c
@@ -0,0 +1,373 @@
+/*
+ * An hwmon driver for the Analog Devices AD7416/17/18
+ * Copyright (C) 2006-07 Tower Technologies
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * Based on lm75.c
+ * Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
+ *
+ * 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 - version 2.
+ */
+
+#include <linux/module.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/delay.h>
+
+#include "lm75.h"
+
+#define DRV_VERSION "0.3"
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { 0x28, I2C_CLIENT_END };
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_3(ad7416, ad7417, ad7418);
+
+/* AD7418 registers */
+#define AD7418_REG_TEMP_IN 0x00
+#define AD7418_REG_CONF 0x01
+#define AD7418_REG_TEMP_HYST 0x02
+#define AD7418_REG_TEMP_OS 0x03
+#define AD7418_REG_ADC 0x04
+#define AD7418_REG_CONF2 0x05
+
+#define AD7418_REG_ADC_CH(x) ((x) << 5)
+#define AD7418_CH_TEMP AD7418_REG_ADC_CH(0)
+
+static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN,
+ AD7418_REG_TEMP_HYST,
+ AD7418_REG_TEMP_OS };
+
+struct ad7418_data {
+ struct i2c_client client;
+ struct class_device *class_dev;
+ struct attribute_group attrs;
+ enum chips type;
+ struct mutex lock;
+ int adc_max; /* number of ADC channels */
+ char valid;
+ unsigned long last_updated; /* In jiffies */
+ s16 temp[3]; /* Register values */
+ u16 in[4];
+};
+
+static int ad7418_attach_adapter(struct i2c_adapter *adapter);
+static int ad7418_detect(struct i2c_adapter *adapter, int address, int kind);
+static int ad7418_detach_client(struct i2c_client *client);
+
+static struct i2c_driver ad7418_driver = {
+ .driver = {
+ .name = "ad7418",
+ },
+ .attach_adapter = ad7418_attach_adapter,
+ .detach_client = ad7418_detach_client,
+};
+
+/* All registers are word-sized, except for the configuration registers.
+ * AD7418 uses a high-byte first convention. Do NOT use those functions to
+ * access the configuration registers CONF and CONF2, as they are byte-sized.
+ */
+static inline int ad7418_read(struct i2c_client *client, u8 reg)
+{
+ return swab16(i2c_smbus_read_word_data(client, reg));
+}
+
+static inline int ad7418_write(struct i2c_client *client, u8 reg, u16 value)
+{
+ return i2c_smbus_write_word_data(client, reg, swab16(value));
+}
+
+static void ad7418_init_client(struct i2c_client *client)
+{
+ struct ad7418_data *data = i2c_get_clientdata(client);
+
+ int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
+ if (reg < 0) {
+ dev_err(&client->dev, "cannot read configuration register\n");
+ } else {
+ dev_info(&client->dev, "configuring for mode 1\n");
+ i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe);
+
+ if (data->type == ad7417 || data->type == ad7418)
+ i2c_smbus_write_byte_data(client,
+ AD7418_REG_CONF2, 0x00);
+ }
+}
+
+static struct ad7418_data *ad7418_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ad7418_data *data = i2c_get_clientdata(client);
+
+ mutex_lock(&data->lock);
+
+ if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+ || !data->valid) {
+ u8 cfg;
+ int i, ch;
+
+ /* read config register and clear channel bits */
+ cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
+ cfg &= 0x1F;
+
+ i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
+ cfg | AD7418_CH_TEMP);
+ udelay(30);
+
+ for (i = 0; i < 3; i++) {
+ data->temp[i] = ad7418_read(client, AD7418_REG_TEMP[i]);
+ }
+
+ for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
+ i2c_smbus_write_byte_data(client,
+ AD7418_REG_CONF,
+ cfg | AD7418_REG_ADC_CH(ch));
+
+ udelay(15);
+ data->in[data->adc_max - 1 - i] =
+ ad7418_read(client, AD7418_REG_ADC);
+ }
+
+ /* restore old configuration value */
+ ad7418_write(client, AD7418_REG_CONF, cfg);
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+
+ mutex_unlock(&data->lock);
+
+ return data;
+}
+
+static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct ad7418_data *data = ad7418_update_device(dev);
+ return sprintf(buf, "%d\n",
+ LM75_TEMP_FROM_REG(data->temp[attr->index]));
+}
+
+static ssize_t show_adc(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct ad7418_data *data = ad7418_update_device(dev);
+
+ return sprintf(buf, "%d\n",
+ ((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
+}
+
+static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ad7418_data *data = i2c_get_clientdata(client);
+ int temp = simple_strtol(buf, NULL, 10);
+
+ mutex_lock(&data->lock);
+ data->temp[attr->index] = LM75_TEMP_TO_REG(temp);
+ ad7418_write(client, AD7418_REG_TEMP[attr->index], data->temp[attr->index]);
+ mutex_unlock(&data->lock);
+ return count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
+ show_temp, set_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+ show_temp, set_temp, 2);
+
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3);
+
+static int ad7418_attach_adapter(struct i2c_adapter *adapter)
+{
+ if (!(adapter->class & I2C_CLASS_HWMON))
+ return 0;
+ return i2c_probe(adapter, &addr_data, ad7418_detect);
+}
+
+static struct attribute *ad7416_attributes[] = {
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ NULL
+};
+
+static struct attribute *ad7417_attributes[] = {
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_in1_input.dev_attr.attr,
+ &sensor_dev_attr_in2_input.dev_attr.attr,
+ &sensor_dev_attr_in3_input.dev_attr.attr,
+ &sensor_dev_attr_in4_input.dev_attr.attr,
+ NULL
+};
+
+static struct attribute *ad7418_attributes[] = {
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_in1_input.dev_attr.attr,
+ NULL
+};
+
+static int ad7418_detect(struct i2c_adapter *adapter, int address, int kind)
+{
+ struct i2c_client *client;
+ struct ad7418_data *data;
+ int err = 0;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA))
+ goto exit;
+
+ if (!(data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL))) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ client = &data->client;
+ client->addr = address;
+ client->adapter = adapter;
+ client->driver = &ad7418_driver;
+
+ i2c_set_clientdata(client, data);
+
+ mutex_init(&data->lock);
+
+ /* AD7418 has a curious behaviour on registers 6 and 7. They
+ * both always read 0xC071 and are not documented on the datasheet.
+ * We use them to detect the chip.
+ */
+ if (kind <= 0) {
+ int reg, reg6, reg7;
+
+ /* the AD7416 lies within this address range, but I have
+ * no means to check.
+ */
+ if (address >= 0x48 && address <= 0x4f) {
+ /* XXX add tests for AD7416 here */
+ /* data->type = ad7416; */
+ }
+ /* here we might have AD7417 or AD7418 */
+ else if (address >= 0x28 && address <= 0x2f) {
+ reg6 = i2c_smbus_read_word_data(client, 0x06);
+ reg7 = i2c_smbus_read_word_data(client, 0x07);
+
+ if (address == 0x28 && reg6 == 0xC071 && reg7 == 0xC071)
+ data->type = ad7418;
+
+ /* XXX add tests for AD7417 here */
+
+
+ /* both AD7417 and AD7418 have bits 0-5 of
+ * the CONF2 register at 0
+ */
+ reg = i2c_smbus_read_byte_data(client,
+ AD7418_REG_CONF2);
+ if (reg & 0x3F)
+ data->type = any_chip; /* detection failed */
+ }
+ } else {
+ dev_dbg(&adapter->dev, "detection forced\n");
+ }
+
+ if (kind > 0)
+ data->type = kind;
+ else if (kind < 0 && data->type == any_chip) {
+ err = -ENODEV;
+ goto exit_free;
+ }
+
+ switch (data->type) {
+ case any_chip:
+ case ad7416:
+ data->adc_max = 0;
+ data->attrs.attrs = ad7416_attributes;
+ strlcpy(client->name, "ad7416", I2C_NAME_SIZE);
+ break;
+
+ case ad7417:
+ data->adc_max = 4;
+ data->attrs.attrs = ad7417_attributes;
+ strlcpy(client->name, "ad7417", I2C_NAME_SIZE);
+ break;
+
+ case ad7418:
+ data->adc_max = 1;
+ data->attrs.attrs = ad7418_attributes;
+ strlcpy(client->name, "ad7418", I2C_NAME_SIZE);
+ break;
+ }
+
+ if ((err = i2c_attach_client(client)))
+ goto exit_free;
+
+ dev_info(&client->dev, "%s chip found\n", client->name);
+
+ /* Initialize the AD7418 chip */
+ ad7418_init_client(client);
+
+ /* Register sysfs hooks */
+ if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs)))
+ goto exit_detach;
+
+ data->class_dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(data->class_dev)) {
+ err = PTR_ERR(data->class_dev);
+ goto exit_remove;
+ }
+
+ return 0;
+
+exit_remove:
+ sysfs_remove_group(&client->dev.kobj, &data->attrs);
+exit_detach:
+ i2c_detach_client(client);
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int ad7418_detach_client(struct i2c_client *client)
+{
+ struct ad7418_data *data = i2c_get_clientdata(client);
+ hwmon_device_unregister(data->class_dev);
+ sysfs_remove_group(&client->dev.kobj, &data->attrs);
+ i2c_detach_client(client);
+ kfree(data);
+ return 0;
+}
+
+static int __init ad7418_init(void)
+{
+ return i2c_add_driver(&ad7418_driver);
+}
+
+static void __exit ad7418_exit(void)
+{
+ i2c_del_driver(&ad7418_driver);
+}
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
+MODULE_DESCRIPTION("AD7416/17/18 driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
+
+module_init(ad7418_init);
+module_exit(ad7418_exit);