diff options
Diffstat (limited to 'drivers/hwmon/adt7411.c')
| -rw-r--r-- | drivers/hwmon/adt7411.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/drivers/hwmon/adt7411.c b/drivers/hwmon/adt7411.c new file mode 100644 index 000000000..827c03703 --- /dev/null +++ b/drivers/hwmon/adt7411.c @@ -0,0 +1,335 @@ +/* + * 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/mutex.h> +#include <linux/jiffies.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/slab.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 */ + struct mutex update_lock; + unsigned long next_update; + int vref_cached; + struct i2c_client *client; +}; + +/* + * 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 adt7411_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + 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 adt7411_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + 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 adt7411_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + int val; + u8 lsb_reg, lsb_shift; + + mutex_lock(&data->update_lock); + if (time_after_eq(jiffies, data->next_update)) { + val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3); + if (val < 0) + goto exit_unlock; + + if (val & ADT7411_CFG3_REF_VDD) { + val = adt7411_read_10_bit(client, + ADT7411_REG_INT_TEMP_VDD_LSB, + ADT7411_REG_VDD_MSB, 2); + if (val < 0) + goto exit_unlock; + + 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); + if (val < 0) + goto exit_unlock; + + val = sprintf(buf, "%u\n", val * data->vref_cached / 1024); + exit_unlock: + mutex_unlock(&data->update_lock); + return val; +} + +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 adt7411_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + 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 adt7411_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + int ret; + unsigned long flag; + + ret = kstrtoul(buf, 0, &flag); + if (ret || flag > 1) + return -EINVAL; + + ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag); + + /* force update */ + mutex_lock(&data->update_lock); + data->next_update = jiffies; + mutex_unlock(&data->update_lock); + + 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 +}; + +ATTRIBUTE_GROUPS(adt7411); + +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 adt7411_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct adt7411_data *data; + struct device *hwmon_dev; + int ret; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + i2c_set_clientdata(client, data); + data->client = client; + mutex_init(&data->device_lock); + mutex_init(&data->update_lock); + + ret = adt7411_modify_bit(client, ADT7411_REG_CFG1, + ADT7411_CFG1_START_MONITOR, 1); + if (ret < 0) + return ret; + + /* force update on first occasion */ + data->next_update = jiffies; + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, + data, + adt7411_groups); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id adt7411_id[] = { + { "adt7411", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, adt7411_id); + +static struct i2c_driver adt7411_driver = { + .driver = { + .name = "adt7411", + }, + .probe = adt7411_probe, + .id_table = adt7411_id, + .detect = adt7411_detect, + .address_list = normal_i2c, + .class = I2C_CLASS_HWMON, +}; + +module_i2c_driver(adt7411_driver); + +MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and " + "Wolfram Sang <w.sang@pengutronix.de>"); +MODULE_DESCRIPTION("ADT7411 driver"); +MODULE_LICENSE("GPL v2"); |