+/*
+ * Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
+ *
+ * Copyright (C) 2008, 2010 Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * TODO: SPI, support for external temperature sensor
+ * use power-down mode for suspend?, interrupt handling?
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#define ADT7411_REG_INT_TEMP_VDD_LSB 0x03
+#define ADT7411_REG_EXT_TEMP_AIN14_LSB 0x04
+#define ADT7411_REG_VDD_MSB 0x06
+#define ADT7411_REG_INT_TEMP_MSB 0x07
+#define ADT7411_REG_EXT_TEMP_AIN1_MSB 0x08
+
+#define ADT7411_REG_CFG1 0x18
+#define ADT7411_CFG1_START_MONITOR (1 << 0)
+
+#define ADT7411_REG_CFG2 0x19
+#define ADT7411_CFG2_DISABLE_AVG (1 << 5)
+
+#define ADT7411_REG_CFG3 0x1a
+#define ADT7411_CFG3_ADC_CLK_225 (1 << 0)
+#define ADT7411_CFG3_REF_VDD (1 << 4)
+
+#define ADT7411_REG_DEVICE_ID 0x4d
+#define ADT7411_REG_MANUFACTURER_ID 0x4e
+
+#define ADT7411_DEVICE_ID 0x2
+#define ADT7411_MANUFACTURER_ID 0x41
+
+static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
+
+struct adt7411_data {
+ struct mutex device_lock; /* for "atomic" device accesses */
+ unsigned long next_update;
+ int vref_cached;
+ bool ref_is_vdd;
+ struct device *hwmon_dev;
+};
+
+/*
+ * When reading a register containing (up to 4) lsb, all associated
+ * msb-registers get locked by the hardware. After _one_ of those msb is read,
+ * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
+ * is protected here with a mutex, too.
+ */
+static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
+ u8 msb_reg, u8 lsb_shift)
+{
+ struct adt7411_data *data = i2c_get_clientdata(client);
+ int val, tmp;
+
+ mutex_lock(&data->device_lock);
+
+ val = i2c_smbus_read_byte_data(client, lsb_reg);
+ if (val < 0)
+ goto exit_unlock;
+
+ tmp = (val >> lsb_shift) & 3;
+ val = i2c_smbus_read_byte_data(client, msb_reg);
+
+ if (val >= 0)
+ val = (val << 2) | tmp;
+
+ exit_unlock:
+ mutex_unlock(&data->device_lock);
+
+ return val;
+}
+
+static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
+ bool flag)
+{
+ struct adt7411_data *data = i2c_get_clientdata(client);
+ int ret, val;
+
+ mutex_lock(&data->device_lock);
+
+ ret = i2c_smbus_read_byte_data(client, reg);
+ if (ret < 0)
+ goto exit_unlock;
+
+ if (flag)
+ val = ret | bit;
+ else
+ val = ret & ~bit;
+
+ ret = i2c_smbus_write_byte_data(client, reg, val);
+
+ exit_unlock:
+ mutex_unlock(&data->device_lock);
+ return ret;
+}
+
+static ssize_t adt7411_show_vdd(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ int ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
+ ADT7411_REG_VDD_MSB, 2);
+
+ return ret < 0 ? ret : sprintf(buf, "%u\n", ret * 7000 / 1024);
+}
+
+static ssize_t adt7411_show_temp(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ int val = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
+ ADT7411_REG_INT_TEMP_MSB, 0);
+
+ if (val < 0)
+ return val;
+
+ val = val & 0x200 ? val - 0x400 : val; /* 10 bit signed */
+
+ return sprintf(buf, "%d\n", val * 250);
+}
+
+static ssize_t adt7411_show_input(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int nr = to_sensor_dev_attr(attr)->index;
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7411_data *data = i2c_get_clientdata(client);
+ int val;
+ u8 lsb_reg, lsb_shift;
+
+ if (time_after_eq(jiffies, data->next_update)) {
+ val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
+ if (val < 0)
+ return val;
+ data->ref_is_vdd = val & ADT7411_CFG3_REF_VDD;
+
+ if (data->ref_is_vdd) {
+ val = adt7411_read_10_bit(client,
+ ADT7411_REG_INT_TEMP_VDD_LSB,
+ ADT7411_REG_VDD_MSB, 2);
+ if (val < 0)
+ return val;
+
+ data->vref_cached = val * 7000 / 1024;
+ } else {
+ data->vref_cached = 2250;
+ }
+
+ data->next_update = jiffies + HZ;
+ }
+
+ lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
+ lsb_shift = 2 * (nr & 0x03);
+ val = adt7411_read_10_bit(client, lsb_reg,
+ ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift);
+
+ return val < 0 ? val :
+ sprintf(buf, "%u\n", val * data->vref_cached / 1024);
+}
+
+static ssize_t adt7411_show_bit(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
+ struct i2c_client *client = to_i2c_client(dev);
+ int ret = i2c_smbus_read_byte_data(client, attr2->index);
+
+ return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
+}
+
+static ssize_t adt7411_set_bit(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t count)
+{
+ struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7411_data *data = i2c_get_clientdata(client);
+ int ret;
+ unsigned long flag;
+
+ ret = strict_strtoul(buf, 0, &flag);
+ if (ret || flag > 1)
+ return -EINVAL;
+
+ ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
+
+ /* force update */
+ data->next_update = jiffies;
+
+ return ret < 0 ? ret : count;
+}
+
+#define ADT7411_BIT_ATTR(__name, __reg, __bit) \
+ SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
+ adt7411_set_bit, __bit, __reg)
+
+static DEVICE_ATTR(temp1_input, S_IRUGO, adt7411_show_temp, NULL);
+static DEVICE_ATTR(in0_input, S_IRUGO, adt7411_show_vdd, NULL);
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, adt7411_show_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, adt7411_show_input, NULL, 1);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, adt7411_show_input, NULL, 2);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, adt7411_show_input, NULL, 3);
+static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, adt7411_show_input, NULL, 4);
+static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, adt7411_show_input, NULL, 5);
+static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, adt7411_show_input, NULL, 6);
+static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, adt7411_show_input, NULL, 7);
+static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
+static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
+static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
+
+static struct attribute *adt7411_attrs[] = {
+ &dev_attr_temp1_input.attr,
+ &dev_attr_in0_input.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,
+ &sensor_dev_attr_in5_input.dev_attr.attr,
+ &sensor_dev_attr_in6_input.dev_attr.attr,
+ &sensor_dev_attr_in7_input.dev_attr.attr,
+ &sensor_dev_attr_in8_input.dev_attr.attr,
+ &sensor_dev_attr_no_average.dev_attr.attr,
+ &sensor_dev_attr_fast_sampling.dev_attr.attr,
+ &sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group adt7411_attr_grp = {
+ .attrs = adt7411_attrs,
+};
+
+static int adt7411_detect(struct i2c_client *client,
+ struct i2c_board_info *info)
+{
+ int val;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
+ if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
+ dev_dbg(&client->dev, "Wrong manufacturer ID. Got %d, "
+ "expected %d\n", val, ADT7411_MANUFACTURER_ID);
+ return -ENODEV;
+ }
+
+ val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
+ if (val < 0 || val != ADT7411_DEVICE_ID) {
+ dev_dbg(&client->dev, "Wrong device ID. Got %d, "
+ "expected %d\n", val, ADT7411_DEVICE_ID);
+ return -ENODEV;
+ }
+
+ strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+static int __devinit adt7411_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct adt7411_data *data;
+ int ret;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->device_lock);
+
+ ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
+ ADT7411_CFG1_START_MONITOR, 1);
+ if (ret < 0)
+ goto exit_free;
+
+ /* force update on first occasion */
+ data->next_update = jiffies;
+
+ ret = sysfs_create_group(&client->dev.kobj, &adt7411_attr_grp);
+ if (ret)
+ goto exit_free;
+
+ data->hwmon_dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ ret = PTR_ERR(data->hwmon_dev);
+ goto exit_remove;
+ }
+
+ dev_info(&client->dev, "successfully registered\n");
+
+ return 0;
+
+ exit_remove:
+ sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
+ exit_free:
+ i2c_set_clientdata(client, NULL);
+ kfree(data);
+ return ret;
+}
+
+static int __devexit adt7411_remove(struct i2c_client *client)
+{
+ struct adt7411_data *data = i2c_get_clientdata(client);
+
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
+ i2c_set_clientdata(client, NULL);
+ kfree(data);
+ return 0;
+}
+
+static const struct i2c_device_id adt7411_id[] = {
+ { "adt7411", 0 },
+ { }
+};
+
+static struct i2c_driver adt7411_driver = {
+ .driver = {
+ .name = "adt7411",
+ },
+ .probe = adt7411_probe,
+ .remove = __devexit_p(adt7411_remove),
+ .id_table = adt7411_id,
+ .detect = adt7411_detect,
+ .address_list = normal_i2c,
+ .class = I2C_CLASS_HWMON,
+};
+
+static int __init sensors_adt7411_init(void)
+{
+ return i2c_add_driver(&adt7411_driver);
+}
+module_init(sensors_adt7411_init)
+
+static void __exit sensors_adt7411_exit(void)
+{
+ i2c_del_driver(&adt7411_driver);
+}
+module_exit(sensors_adt7411_exit)
+
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
+ "Wolfram Sang <w.sang@pengutronix.de>");
+MODULE_DESCRIPTION("ADT7411 driver");
+MODULE_LICENSE("GPL v2");
git.openpandora.org / pandora-kernel.git / commitdiff