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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Driver for Linear Technology LTC2990 power monitor4 *5 * Copyright (C) 2014 Topic Embedded Products6 * Author: Mike Looijmans <mike.looijmans@topic.nl>7 */8 9#include <linux/bitops.h>10#include <linux/err.h>11#include <linux/hwmon.h>12#include <linux/hwmon-sysfs.h>13#include <linux/i2c.h>14#include <linux/kernel.h>15#include <linux/module.h>16#include <linux/property.h>17 18#define LTC2990_STATUS 0x0019#define LTC2990_CONTROL 0x0120#define LTC2990_TRIGGER 0x0221#define LTC2990_TINT_MSB 0x0422#define LTC2990_V1_MSB 0x0623#define LTC2990_V2_MSB 0x0824#define LTC2990_V3_MSB 0x0A25#define LTC2990_V4_MSB 0x0C26#define LTC2990_VCC_MSB 0x0E27 28#define LTC2990_IN0 BIT(0)29#define LTC2990_IN1 BIT(1)30#define LTC2990_IN2 BIT(2)31#define LTC2990_IN3 BIT(3)32#define LTC2990_IN4 BIT(4)33#define LTC2990_CURR1 BIT(5)34#define LTC2990_CURR2 BIT(6)35#define LTC2990_TEMP1 BIT(7)36#define LTC2990_TEMP2 BIT(8)37#define LTC2990_TEMP3 BIT(9)38#define LTC2990_NONE 039#define LTC2990_ALL GENMASK(9, 0)40 41#define LTC2990_MODE0_SHIFT 042#define LTC2990_MODE0_MASK GENMASK(2, 0)43#define LTC2990_MODE1_SHIFT 344#define LTC2990_MODE1_MASK GENMASK(1, 0)45 46/* Enabled measurements for mode bits 2..0 */47static const int ltc2990_attrs_ena_0[] = {48 LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,49 LTC2990_CURR1 | LTC2990_TEMP3,50 LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,51 LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,52 LTC2990_TEMP2 | LTC2990_CURR2,53 LTC2990_TEMP2 | LTC2990_TEMP3,54 LTC2990_CURR1 | LTC2990_CURR2,55 LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN456};57 58/* Enabled measurements for mode bits 4..3 */59static const int ltc2990_attrs_ena_1[] = {60 LTC2990_NONE,61 LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,62 LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,63 LTC2990_ALL64};65 66struct ltc2990_data {67 struct i2c_client *i2c;68 u32 mode[2];69};70 71/* Return the converted value from the given register in uV or mC */72static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result)73{74 int val;75 u8 reg;76 77 switch (index) {78 case LTC2990_IN0:79 reg = LTC2990_VCC_MSB;80 break;81 case LTC2990_IN1:82 case LTC2990_CURR1:83 case LTC2990_TEMP2:84 reg = LTC2990_V1_MSB;85 break;86 case LTC2990_IN2:87 reg = LTC2990_V2_MSB;88 break;89 case LTC2990_IN3:90 case LTC2990_CURR2:91 case LTC2990_TEMP3:92 reg = LTC2990_V3_MSB;93 break;94 case LTC2990_IN4:95 reg = LTC2990_V4_MSB;96 break;97 case LTC2990_TEMP1:98 reg = LTC2990_TINT_MSB;99 break;100 default:101 return -EINVAL;102 }103 104 val = i2c_smbus_read_word_swapped(i2c, reg);105 if (unlikely(val < 0))106 return val;107 108 switch (index) {109 case LTC2990_TEMP1:110 case LTC2990_TEMP2:111 case LTC2990_TEMP3:112 /* temp, 0.0625 degrees/LSB */113 *result = sign_extend32(val, 12) * 1000 / 16;114 break;115 case LTC2990_CURR1:116 case LTC2990_CURR2:117 /* Vx-Vy, 19.42uV/LSB */118 *result = sign_extend32(val, 14) * 1942 / 100;119 break;120 case LTC2990_IN0:121 /* Vcc, 305.18uV/LSB, 2.5V offset */122 *result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;123 break;124 case LTC2990_IN1:125 case LTC2990_IN2:126 case LTC2990_IN3:127 case LTC2990_IN4:128 /* Vx, 305.18uV/LSB */129 *result = sign_extend32(val, 14) * 30518 / (100 * 1000);130 break;131 default:132 return -EINVAL; /* won't happen, keep compiler happy */133 }134 135 return 0;136}137 138static ssize_t ltc2990_value_show(struct device *dev,139 struct device_attribute *da, char *buf)140{141 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);142 struct ltc2990_data *data = dev_get_drvdata(dev);143 int value;144 int ret;145 146 ret = ltc2990_get_value(data->i2c, attr->index, &value);147 if (unlikely(ret < 0))148 return ret;149 150 return sysfs_emit(buf, "%d\n", value);151}152 153static umode_t ltc2990_attrs_visible(struct kobject *kobj,154 struct attribute *a, int n)155{156 struct device *dev = kobj_to_dev(kobj);157 struct ltc2990_data *data = dev_get_drvdata(dev);158 struct device_attribute *da =159 container_of(a, struct device_attribute, attr);160 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);161 162 int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |163 (ltc2990_attrs_ena_0[data->mode[0]] &164 ltc2990_attrs_ena_1[data->mode[1]]);165 166 if (attr->index & attrs_mask)167 return a->mode;168 169 return 0;170}171 172static SENSOR_DEVICE_ATTR_RO(temp1_input, ltc2990_value, LTC2990_TEMP1);173static SENSOR_DEVICE_ATTR_RO(temp2_input, ltc2990_value, LTC2990_TEMP2);174static SENSOR_DEVICE_ATTR_RO(temp3_input, ltc2990_value, LTC2990_TEMP3);175static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2990_value, LTC2990_CURR1);176static SENSOR_DEVICE_ATTR_RO(curr2_input, ltc2990_value, LTC2990_CURR2);177static SENSOR_DEVICE_ATTR_RO(in0_input, ltc2990_value, LTC2990_IN0);178static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2990_value, LTC2990_IN1);179static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2990_value, LTC2990_IN2);180static SENSOR_DEVICE_ATTR_RO(in3_input, ltc2990_value, LTC2990_IN3);181static SENSOR_DEVICE_ATTR_RO(in4_input, ltc2990_value, LTC2990_IN4);182 183static struct attribute *ltc2990_attrs[] = {184 &sensor_dev_attr_temp1_input.dev_attr.attr,185 &sensor_dev_attr_temp2_input.dev_attr.attr,186 &sensor_dev_attr_temp3_input.dev_attr.attr,187 &sensor_dev_attr_curr1_input.dev_attr.attr,188 &sensor_dev_attr_curr2_input.dev_attr.attr,189 &sensor_dev_attr_in0_input.dev_attr.attr,190 &sensor_dev_attr_in1_input.dev_attr.attr,191 &sensor_dev_attr_in2_input.dev_attr.attr,192 &sensor_dev_attr_in3_input.dev_attr.attr,193 &sensor_dev_attr_in4_input.dev_attr.attr,194 NULL,195};196 197static const struct attribute_group ltc2990_group = {198 .attrs = ltc2990_attrs,199 .is_visible = ltc2990_attrs_visible,200};201__ATTRIBUTE_GROUPS(ltc2990);202 203static int ltc2990_i2c_probe(struct i2c_client *i2c)204{205 int ret;206 struct device *hwmon_dev;207 struct ltc2990_data *data;208 209 if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |210 I2C_FUNC_SMBUS_WORD_DATA))211 return -ENODEV;212 213 data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);214 if (unlikely(!data))215 return -ENOMEM;216 217 data->i2c = i2c;218 219 if (dev_fwnode(&i2c->dev)) {220 ret = device_property_read_u32_array(&i2c->dev,221 "lltc,meas-mode",222 data->mode, 2);223 if (ret < 0)224 return ret;225 226 if (data->mode[0] & ~LTC2990_MODE0_MASK ||227 data->mode[1] & ~LTC2990_MODE1_MASK)228 return -EINVAL;229 } else {230 ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);231 if (ret < 0)232 return ret;233 234 data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK;235 data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK;236 }237 238 /* Setup continuous mode */239 ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,240 data->mode[0] << LTC2990_MODE0_SHIFT |241 data->mode[1] << LTC2990_MODE1_SHIFT);242 if (ret < 0) {243 dev_err(&i2c->dev, "Error: Failed to set control mode.\n");244 return ret;245 }246 /* Trigger once to start continuous conversion */247 ret = i2c_smbus_write_byte_data(i2c, LTC2990_TRIGGER, 1);248 if (ret < 0) {249 dev_err(&i2c->dev, "Error: Failed to start acquisition.\n");250 return ret;251 }252 253 hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,254 i2c->name,255 data,256 ltc2990_groups);257 258 return PTR_ERR_OR_ZERO(hwmon_dev);259}260 261static const struct i2c_device_id ltc2990_i2c_id[] = {262 { "ltc2990" },263 {}264};265MODULE_DEVICE_TABLE(i2c, ltc2990_i2c_id);266 267static struct i2c_driver ltc2990_i2c_driver = {268 .driver = {269 .name = "ltc2990",270 },271 .probe = ltc2990_i2c_probe,272 .id_table = ltc2990_i2c_id,273};274 275module_i2c_driver(ltc2990_i2c_driver);276 277MODULE_DESCRIPTION("LTC2990 Sensor Driver");278MODULE_AUTHOR("Topic Embedded Products");279MODULE_LICENSE("GPL v2");280