// SPDX-License-Identifier: GPL-2.0-only /* * LM73 Sensor driver * Based on LM75 * * Copyright (C) 2007, CenoSYS (www.cenosys.com). * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu). * * Guillaume Ligneul <guillaume.ligneul@gmail.com> * Adrien Demarez <adrien.demarez@bolloretelecom.eu> * Jeremy Laine <jeremy.laine@bolloretelecom.eu> * Chris Verges <kg4ysn@gmail.com> */ #include <linux/module.h> #include <linux/init.h> #include <linux/i2c.h> #include <linux/hwmon.h> #include <linux/hwmon-sysfs.h> #include <linux/err.h> /* Addresses scanned */ static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; /* LM73 registers */ #define LM73_REG_INPUT 0x00 #define LM73_REG_CONF 0x01 #define LM73_REG_MAX 0x02 #define LM73_REG_MIN 0x03 #define LM73_REG_CTRL 0x04 #define LM73_REG_ID 0x07 #define LM73_ID 0x9001 /* 0x0190, byte-swapped */ #define DRVNAME "lm73" #define LM73_TEMP_MIN (-256000 / 250) #define LM73_TEMP_MAX (255750 / 250) #define LM73_CTRL_RES_SHIFT 5 #define LM73_CTRL_RES_MASK (BIT(5) | BIT(6)) #define LM73_CTRL_TO_MASK BIT(7) #define LM73_CTRL_HI_SHIFT 2 #define LM73_CTRL_LO_SHIFT 1 static const unsigned short lm73_convrates[] = { 14, /* 11-bits (0.25000 C/LSB): RES1 Bit = 0, RES0 Bit = 0 */ 28, /* 12-bits (0.12500 C/LSB): RES1 Bit = 0, RES0 Bit = 1 */ 56, /* 13-bits (0.06250 C/LSB): RES1 Bit = 1, RES0 Bit = 0 */ 112, /* 14-bits (0.03125 C/LSB): RES1 Bit = 1, RES0 Bit = 1 */ }; struct lm73_data { struct i2c_client *client; struct mutex lock; u8 ctrl; /* control register value */ }; /*-----------------------------------------------------------------------*/ static ssize_t temp_store(struct device *dev, struct device_attribute *da, const char *buf, size_t count) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct lm73_data *data = dev_get_drvdata(dev); long temp; short value; s32 err; int status = kstrtol(buf, 10, &temp); if (status < 0) return status; /* Write value */ value = clamp_val(temp / 250, LM73_TEMP_MIN, LM73_TEMP_MAX) << 5; err = i2c_smbus_write_word_swapped(data->client, attr->index, value); return (err < 0) ? err : count; } static ssize_t temp_show(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct lm73_data *data = dev_get_drvdata(dev); int temp; s32 err = i2c_smbus_read_word_swapped(data->client, attr->index); if (err < 0) return err; /* use integer division instead of equivalent right shift to guarantee arithmetic shift and preserve the sign */ temp = (((s16) err) * 250) / 32; return sysfs_emit(buf, "%d\n", temp); } static ssize_t convrate_store(struct device *dev, struct device_attribute *da, const char *buf, size_t count) { struct lm73_data *data = dev_get_drvdata(dev); unsigned long convrate; s32 err; int res = 0; err = kstrtoul(buf, 10, &convrate); if (err < 0) return err; /* * Convert the desired conversion rate into register bits. * res is already initialized, and everything past the second-to-last * value in the array is treated as belonging to the last value * in the array. */ while (res < (ARRAY_SIZE(lm73_convrates) - 1) && convrate > lm73_convrates[res]) res++; mutex_lock(&data->lock); data->ctrl &= LM73_CTRL_TO_MASK; data->ctrl |= res << LM73_CTRL_RES_SHIFT; err = i2c_smbus_write_byte_data(data->client, LM73_REG_CTRL, data->ctrl); mutex_unlock(&data->lock); if (err < 0) return err; return count; } static ssize_t convrate_show(struct device *dev, struct device_attribute *da, char *buf) { struct lm73_data *data = dev_get_drvdata(dev); int res; res = (data->ctrl & LM73_CTRL_RES_MASK) >> LM73_CTRL_RES_SHIFT; return sysfs_emit(buf, "%hu\n", lm73_convrates[res]); } static ssize_t maxmin_alarm_show(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct lm73_data *data = dev_get_drvdata(dev); s32 ctrl; mutex_lock(&data->lock); ctrl = i2c_smbus_read_byte_data(data->client, LM73_REG_CTRL); if (ctrl < 0) goto abort; data->ctrl = ctrl; mutex_unlock(&data->lock); return sysfs_emit(buf, "%d\n", (ctrl >> attr->index) & 1); abort: mutex_unlock(&data->lock); return ctrl; } /*-----------------------------------------------------------------------*/ /* sysfs attributes for hwmon */ static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, LM73_REG_MAX); static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, LM73_REG_MIN); static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, LM73_REG_INPUT); static SENSOR_DEVICE_ATTR_RW(update_interval, convrate, 0); static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, maxmin_alarm, LM73_CTRL_HI_SHIFT); static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, maxmin_alarm, LM73_CTRL_LO_SHIFT); static struct attribute *lm73_attrs[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, &sensor_dev_attr_temp1_max.dev_attr.attr, &sensor_dev_attr_temp1_min.dev_attr.attr, &sensor_dev_attr_update_interval.dev_attr.attr, &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, NULL }; ATTRIBUTE_GROUPS(lm73); /*-----------------------------------------------------------------------*/ /* device probe and removal */ static int lm73_probe(struct i2c_client *client) { struct device *dev = &client->dev; struct device *hwmon_dev; struct lm73_data *data; int ctrl; data = devm_kzalloc(dev, sizeof(struct lm73_data), GFP_KERNEL); if (!data) return -ENOMEM; data->client = client; mutex_init(&data->lock); ctrl = i2c_smbus_read_byte_data(client, LM73_REG_CTRL); if (ctrl < 0) return ctrl; data->ctrl = ctrl; hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, data, lm73_groups); if (IS_ERR(hwmon_dev)) return PTR_ERR(hwmon_dev); dev_info(dev, "sensor '%s'\n", client->name); return 0; } static const struct i2c_device_id lm73_ids[] = { { "lm73", 0 }, { /* LIST END */ } }; MODULE_DEVICE_TABLE(i2c, lm73_ids); /* Return 0 if detection is successful, -ENODEV otherwise */ static int lm73_detect(struct i2c_client *new_client, struct i2c_board_info *info) { struct i2c_adapter *adapter = new_client->adapter; int id, ctrl, conf; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA)) return -ENODEV; /* * Do as much detection as possible with byte reads first, as word * reads can confuse other devices. */ ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL); if (ctrl < 0 || (ctrl & 0x10)) return -ENODEV; conf = i2c_smbus_read_byte_data(new_client, LM73_REG_CONF); if (conf < 0 || (conf & 0x0c)) return -ENODEV; id = i2c_smbus_read_byte_data(new_client, LM73_REG_ID); if (id < 0 || id != (LM73_ID & 0xff)) return -ENODEV; /* Check device ID */ id = i2c_smbus_read_word_data(new_client, LM73_REG_ID); if (id < 0 || id != LM73_ID) return -ENODEV; strscpy(info->type, "lm73", I2C_NAME_SIZE); return 0; } static const struct of_device_id lm73_of_match[] = { { .compatible = "ti,lm73", }, { }, }; MODULE_DEVICE_TABLE(of, lm73_of_match); static struct i2c_driver lm73_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "lm73", .of_match_table = lm73_of_match, }, .probe = lm73_probe, .id_table = lm73_ids, .detect = lm73_detect, .address_list = normal_i2c, }; module_i2c_driver(lm73_driver); MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>"); MODULE_DESCRIPTION("LM73 driver"); MODULE_LICENSE("GPL");