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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * LM73 Sensor driver4 * Based on LM755 *6 * Copyright (C) 2007, CenoSYS (www.cenosys.com).7 * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu).8 *9 * Guillaume Ligneul <guillaume.ligneul@gmail.com>10 * Adrien Demarez <adrien.demarez@bolloretelecom.eu>11 * Jeremy Laine <jeremy.laine@bolloretelecom.eu>12 * Chris Verges <kg4ysn@gmail.com>13 */14 15#include <linux/module.h>16#include <linux/init.h>17#include <linux/i2c.h>18#include <linux/hwmon.h>19#include <linux/hwmon-sysfs.h>20#include <linux/err.h>21 22 23/* Addresses scanned */24static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c,25 0x4d, 0x4e, I2C_CLIENT_END };26 27/* LM73 registers */28#define LM73_REG_INPUT 0x0029#define LM73_REG_CONF 0x0130#define LM73_REG_MAX 0x0231#define LM73_REG_MIN 0x0332#define LM73_REG_CTRL 0x0433#define LM73_REG_ID 0x0734 35#define LM73_ID 0x9001 /* 0x0190, byte-swapped */36#define DRVNAME "lm73"37#define LM73_TEMP_MIN (-256000 / 250)38#define LM73_TEMP_MAX (255750 / 250)39 40#define LM73_CTRL_RES_SHIFT 541#define LM73_CTRL_RES_MASK (BIT(5) | BIT(6))42#define LM73_CTRL_TO_MASK BIT(7)43 44#define LM73_CTRL_HI_SHIFT 245#define LM73_CTRL_LO_SHIFT 146 47static const unsigned short lm73_convrates[] = {48 14, /* 11-bits (0.25000 C/LSB): RES1 Bit = 0, RES0 Bit = 0 */49 28, /* 12-bits (0.12500 C/LSB): RES1 Bit = 0, RES0 Bit = 1 */50 56, /* 13-bits (0.06250 C/LSB): RES1 Bit = 1, RES0 Bit = 0 */51 112, /* 14-bits (0.03125 C/LSB): RES1 Bit = 1, RES0 Bit = 1 */52};53 54struct lm73_data {55 struct i2c_client *client;56 struct mutex lock;57 u8 ctrl; /* control register value */58};59 60/*-----------------------------------------------------------------------*/61 62static ssize_t temp_store(struct device *dev, struct device_attribute *da,63 const char *buf, size_t count)64{65 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);66 struct lm73_data *data = dev_get_drvdata(dev);67 long temp;68 short value;69 s32 err;70 71 int status = kstrtol(buf, 10, &temp);72 if (status < 0)73 return status;74 75 /* Write value */76 value = clamp_val(temp / 250, LM73_TEMP_MIN, LM73_TEMP_MAX) << 5;77 err = i2c_smbus_write_word_swapped(data->client, attr->index, value);78 return (err < 0) ? err : count;79}80 81static ssize_t temp_show(struct device *dev, struct device_attribute *da,82 char *buf)83{84 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);85 struct lm73_data *data = dev_get_drvdata(dev);86 int temp;87 88 s32 err = i2c_smbus_read_word_swapped(data->client, attr->index);89 if (err < 0)90 return err;91 92 /* use integer division instead of equivalent right shift to93 guarantee arithmetic shift and preserve the sign */94 temp = (((s16) err) * 250) / 32;95 return sysfs_emit(buf, "%d\n", temp);96}97 98static ssize_t convrate_store(struct device *dev, struct device_attribute *da,99 const char *buf, size_t count)100{101 struct lm73_data *data = dev_get_drvdata(dev);102 unsigned long convrate;103 s32 err;104 int res = 0;105 106 err = kstrtoul(buf, 10, &convrate);107 if (err < 0)108 return err;109 110 /*111 * Convert the desired conversion rate into register bits.112 * res is already initialized, and everything past the second-to-last113 * value in the array is treated as belonging to the last value114 * in the array.115 */116 while (res < (ARRAY_SIZE(lm73_convrates) - 1) &&117 convrate > lm73_convrates[res])118 res++;119 120 mutex_lock(&data->lock);121 data->ctrl &= LM73_CTRL_TO_MASK;122 data->ctrl |= res << LM73_CTRL_RES_SHIFT;123 err = i2c_smbus_write_byte_data(data->client, LM73_REG_CTRL,124 data->ctrl);125 mutex_unlock(&data->lock);126 127 if (err < 0)128 return err;129 130 return count;131}132 133static ssize_t convrate_show(struct device *dev, struct device_attribute *da,134 char *buf)135{136 struct lm73_data *data = dev_get_drvdata(dev);137 int res;138 139 res = (data->ctrl & LM73_CTRL_RES_MASK) >> LM73_CTRL_RES_SHIFT;140 return sysfs_emit(buf, "%hu\n", lm73_convrates[res]);141}142 143static ssize_t maxmin_alarm_show(struct device *dev,144 struct device_attribute *da, char *buf)145{146 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);147 struct lm73_data *data = dev_get_drvdata(dev);148 s32 ctrl;149 150 mutex_lock(&data->lock);151 ctrl = i2c_smbus_read_byte_data(data->client, LM73_REG_CTRL);152 if (ctrl < 0)153 goto abort;154 data->ctrl = ctrl;155 mutex_unlock(&data->lock);156 157 return sysfs_emit(buf, "%d\n", (ctrl >> attr->index) & 1);158 159abort:160 mutex_unlock(&data->lock);161 return ctrl;162}163 164/*-----------------------------------------------------------------------*/165 166/* sysfs attributes for hwmon */167 168static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, LM73_REG_MAX);169static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, LM73_REG_MIN);170static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, LM73_REG_INPUT);171static SENSOR_DEVICE_ATTR_RW(update_interval, convrate, 0);172static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, maxmin_alarm,173 LM73_CTRL_HI_SHIFT);174static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, maxmin_alarm,175 LM73_CTRL_LO_SHIFT);176 177static struct attribute *lm73_attrs[] = {178 &sensor_dev_attr_temp1_input.dev_attr.attr,179 &sensor_dev_attr_temp1_max.dev_attr.attr,180 &sensor_dev_attr_temp1_min.dev_attr.attr,181 &sensor_dev_attr_update_interval.dev_attr.attr,182 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,183 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,184 NULL185};186ATTRIBUTE_GROUPS(lm73);187 188/*-----------------------------------------------------------------------*/189 190/* device probe and removal */191 192static int193lm73_probe(struct i2c_client *client)194{195 struct device *dev = &client->dev;196 struct device *hwmon_dev;197 struct lm73_data *data;198 int ctrl;199 200 data = devm_kzalloc(dev, sizeof(struct lm73_data), GFP_KERNEL);201 if (!data)202 return -ENOMEM;203 204 data->client = client;205 mutex_init(&data->lock);206 207 ctrl = i2c_smbus_read_byte_data(client, LM73_REG_CTRL);208 if (ctrl < 0)209 return ctrl;210 data->ctrl = ctrl;211 212 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,213 data, lm73_groups);214 if (IS_ERR(hwmon_dev))215 return PTR_ERR(hwmon_dev);216 217 dev_info(dev, "sensor '%s'\n", client->name);218 219 return 0;220}221 222static const struct i2c_device_id lm73_ids[] = {223 { "lm73" },224 { /* LIST END */ }225};226MODULE_DEVICE_TABLE(i2c, lm73_ids);227 228/* Return 0 if detection is successful, -ENODEV otherwise */229static int lm73_detect(struct i2c_client *new_client,230 struct i2c_board_info *info)231{232 struct i2c_adapter *adapter = new_client->adapter;233 int id, ctrl, conf;234 235 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |236 I2C_FUNC_SMBUS_WORD_DATA))237 return -ENODEV;238 239 /*240 * Do as much detection as possible with byte reads first, as word241 * reads can confuse other devices.242 */243 ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL);244 if (ctrl < 0 || (ctrl & 0x10))245 return -ENODEV;246 247 conf = i2c_smbus_read_byte_data(new_client, LM73_REG_CONF);248 if (conf < 0 || (conf & 0x0c))249 return -ENODEV;250 251 id = i2c_smbus_read_byte_data(new_client, LM73_REG_ID);252 if (id < 0 || id != (LM73_ID & 0xff))253 return -ENODEV;254 255 /* Check device ID */256 id = i2c_smbus_read_word_data(new_client, LM73_REG_ID);257 if (id < 0 || id != LM73_ID)258 return -ENODEV;259 260 strscpy(info->type, "lm73", I2C_NAME_SIZE);261 262 return 0;263}264 265static const struct of_device_id lm73_of_match[] = {266 {267 .compatible = "ti,lm73",268 },269 { },270};271 272MODULE_DEVICE_TABLE(of, lm73_of_match);273 274static struct i2c_driver lm73_driver = {275 .class = I2C_CLASS_HWMON,276 .driver = {277 .name = "lm73",278 .of_match_table = lm73_of_match,279 },280 .probe = lm73_probe,281 .id_table = lm73_ids,282 .detect = lm73_detect,283 .address_list = normal_i2c,284};285 286module_i2c_driver(lm73_driver);287 288MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>");289MODULE_DESCRIPTION("LM73 driver");290MODULE_LICENSE("GPL");291