/* * 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 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; 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 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 = 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 }; 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 = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; i2c_set_clientdata(client, data); 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; ret = sysfs_create_group(&client->dev.kobj, &adt7411_attr_grp); if (ret) return ret; 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); 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); return 0; } 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, .remove = __devexit_p(adt7411_remove), .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");