1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Driver for Linear Technology LTC2990 power monitor 4 * 5 * Copyright (C) 2014 Topic Embedded Products 6 * 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 0x00 19 #define LTC2990_CONTROL 0x01 20 #define LTC2990_TRIGGER 0x02 21 #define LTC2990_TINT_MSB 0x04 22 #define LTC2990_V1_MSB 0x06 23 #define LTC2990_V2_MSB 0x08 24 #define LTC2990_V3_MSB 0x0A 25 #define LTC2990_V4_MSB 0x0C 26 #define LTC2990_VCC_MSB 0x0E 27 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 0 39 #define LTC2990_ALL GENMASK(9, 0) 40 41 #define LTC2990_MODE0_SHIFT 0 42 #define LTC2990_MODE0_MASK GENMASK(2, 0) 43 #define LTC2990_MODE1_SHIFT 3 44 #define LTC2990_MODE1_MASK GENMASK(1, 0) 45 46 /* Enabled measurements for mode bits 2..0 */ 47 static 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_IN4 56 }; 57 58 /* Enabled measurements for mode bits 4..3 */ 59 static 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_ALL 64 }; 65 66 struct 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 */ 72 static 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 } 137 138 static 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 snprintf(buf, PAGE_SIZE, "%d\n", value); 151 } 152 153 static umode_t ltc2990_attrs_visible(struct kobject *kobj, 154 struct attribute *a, int n) 155 { 156 struct device *dev = container_of(kobj, struct device, 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 } 171 172 static SENSOR_DEVICE_ATTR_RO(temp1_input, ltc2990_value, LTC2990_TEMP1); 173 static SENSOR_DEVICE_ATTR_RO(temp2_input, ltc2990_value, LTC2990_TEMP2); 174 static SENSOR_DEVICE_ATTR_RO(temp3_input, ltc2990_value, LTC2990_TEMP3); 175 static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2990_value, LTC2990_CURR1); 176 static SENSOR_DEVICE_ATTR_RO(curr2_input, ltc2990_value, LTC2990_CURR2); 177 static SENSOR_DEVICE_ATTR_RO(in0_input, ltc2990_value, LTC2990_IN0); 178 static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2990_value, LTC2990_IN1); 179 static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2990_value, LTC2990_IN2); 180 static SENSOR_DEVICE_ATTR_RO(in3_input, ltc2990_value, LTC2990_IN3); 181 static SENSOR_DEVICE_ATTR_RO(in4_input, ltc2990_value, LTC2990_IN4); 182 183 static 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 }; 196 197 static const struct attribute_group ltc2990_group = { 198 .attrs = ltc2990_attrs, 199 .is_visible = ltc2990_attrs_visible, 200 }; 201 __ATTRIBUTE_GROUPS(ltc2990); 202 203 static 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 } 260 261 static const struct i2c_device_id ltc2990_i2c_id[] = { 262 { "ltc2990", 0 }, 263 {} 264 }; 265 MODULE_DEVICE_TABLE(i2c, ltc2990_i2c_id); 266 267 static struct i2c_driver ltc2990_i2c_driver = { 268 .driver = { 269 .name = "ltc2990", 270 }, 271 .probe_new = ltc2990_i2c_probe, 272 .id_table = ltc2990_i2c_id, 273 }; 274 275 module_i2c_driver(ltc2990_i2c_driver); 276 277 MODULE_DESCRIPTION("LTC2990 Sensor Driver"); 278 MODULE_AUTHOR("Topic Embedded Products"); 279 MODULE_LICENSE("GPL v2"); 280