// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2008, 2010 Davide Rizzo <elpa.rizzo@gmail.com> * * The LM95241 is a sensor chip made by National Semiconductors. * It reports up to three temperatures (its own plus up to two external ones). * Complete datasheet can be obtained from National's website at: * http://www.national.com/ds.cgi/LM/LM95241.pdf */ #include <linux/bitops.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/jiffies.h> #include <linux/hwmon.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/slab.h> #define DEVNAME "lm95241" static const unsigned short normal_i2c[] = { 0x19, 0x2a, 0x2b, I2C_CLIENT_END }; /* LM95241 registers */ #define LM95241_REG_R_MAN_ID 0xFE #define LM95241_REG_R_CHIP_ID 0xFF #define LM95241_REG_R_STATUS 0x02 #define LM95241_REG_RW_CONFIG 0x03 #define LM95241_REG_RW_REM_FILTER 0x06 #define LM95241_REG_RW_TRUTHERM 0x07 #define LM95241_REG_W_ONE_SHOT 0x0F #define LM95241_REG_R_LOCAL_TEMPH 0x10 #define LM95241_REG_R_REMOTE1_TEMPH 0x11 #define LM95241_REG_R_REMOTE2_TEMPH 0x12 #define LM95241_REG_R_LOCAL_TEMPL 0x20 #define LM95241_REG_R_REMOTE1_TEMPL 0x21 #define LM95241_REG_R_REMOTE2_TEMPL 0x22 #define LM95241_REG_RW_REMOTE_MODEL 0x30 /* LM95241 specific bitfields */ #define CFG_STOP BIT(6) #define CFG_CR0076 0x00 #define CFG_CR0182 BIT(4) #define CFG_CR1000 BIT(5) #define CFG_CR2700 (BIT(4) | BIT(5)) #define CFG_CRMASK (BIT(4) | BIT(5)) #define R1MS_MASK BIT(0) #define R2MS_MASK BIT(2) #define R1DF_MASK BIT(1) #define R2DF_MASK BIT(2) #define R1FE_MASK BIT(0) #define R2FE_MASK BIT(2) #define R1DM BIT(0) #define R2DM BIT(1) #define TT1_SHIFT 0 #define TT2_SHIFT 4 #define TT_OFF 0 #define TT_ON 1 #define TT_MASK 7 #define NATSEMI_MAN_ID 0x01 #define LM95231_CHIP_ID 0xA1 #define LM95241_CHIP_ID 0xA4 static const u8 lm95241_reg_address[] = { LM95241_REG_R_LOCAL_TEMPH, LM95241_REG_R_LOCAL_TEMPL, LM95241_REG_R_REMOTE1_TEMPH, LM95241_REG_R_REMOTE1_TEMPL, LM95241_REG_R_REMOTE2_TEMPH, LM95241_REG_R_REMOTE2_TEMPL }; /* Client data (each client gets its own) */ struct lm95241_data { struct i2c_client *client; struct mutex update_lock; unsigned long last_updated; /* in jiffies */ unsigned long interval; /* in milli-seconds */ char valid; /* zero until following fields are valid */ /* registers values */ u8 temp[ARRAY_SIZE(lm95241_reg_address)]; u8 status, config, model, trutherm; }; /* Conversions */ static int temp_from_reg_signed(u8 val_h, u8 val_l) { s16 val_hl = (val_h << 8) | val_l; return val_hl * 1000 / 256; } static int temp_from_reg_unsigned(u8 val_h, u8 val_l) { u16 val_hl = (val_h << 8) | val_l; return val_hl * 1000 / 256; } static struct lm95241_data *lm95241_update_device(struct device *dev) { struct lm95241_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; mutex_lock(&data->update_lock); if (time_after(jiffies, data->last_updated + msecs_to_jiffies(data->interval)) || !data->valid) { int i; dev_dbg(dev, "Updating lm95241 data.\n"); for (i = 0; i < ARRAY_SIZE(lm95241_reg_address); i++) data->temp[i] = i2c_smbus_read_byte_data(client, lm95241_reg_address[i]); data->status = i2c_smbus_read_byte_data(client, LM95241_REG_R_STATUS); data->last_updated = jiffies; data->valid = 1; } mutex_unlock(&data->update_lock); return data; } static int lm95241_read_chip(struct device *dev, u32 attr, int channel, long *val) { struct lm95241_data *data = dev_get_drvdata(dev); switch (attr) { case hwmon_chip_update_interval: *val = data->interval; return 0; default: return -EOPNOTSUPP; } } static int lm95241_read_temp(struct device *dev, u32 attr, int channel, long *val) { struct lm95241_data *data = lm95241_update_device(dev); switch (attr) { case hwmon_temp_input: if (!channel || (data->config & BIT(channel - 1))) *val = temp_from_reg_signed(data->temp[channel * 2], data->temp[channel * 2 + 1]); else *val = temp_from_reg_unsigned(data->temp[channel * 2], data->temp[channel * 2 + 1]); return 0; case hwmon_temp_min: if (channel == 1) *val = (data->config & R1DF_MASK) ? -128000 : 0; else *val = (data->config & R2DF_MASK) ? -128000 : 0; return 0; case hwmon_temp_max: if (channel == 1) *val = (data->config & R1DF_MASK) ? 127875 : 255875; else *val = (data->config & R2DF_MASK) ? 127875 : 255875; return 0; case hwmon_temp_type: if (channel == 1) *val = (data->model & R1MS_MASK) ? 1 : 2; else *val = (data->model & R2MS_MASK) ? 1 : 2; return 0; case hwmon_temp_fault: if (channel == 1) *val = !!(data->status & R1DM); else *val = !!(data->status & R2DM); return 0; default: return -EOPNOTSUPP; } } static int lm95241_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *val) { switch (type) { case hwmon_chip: return lm95241_read_chip(dev, attr, channel, val); case hwmon_temp: return lm95241_read_temp(dev, attr, channel, val); default: return -EOPNOTSUPP; } } static int lm95241_write_chip(struct device *dev, u32 attr, int channel, long val) { struct lm95241_data *data = dev_get_drvdata(dev); int convrate; u8 config; int ret; mutex_lock(&data->update_lock); switch (attr) { case hwmon_chip_update_interval: config = data->config & ~CFG_CRMASK; if (val < 130) { convrate = 76; config |= CFG_CR0076; } else if (val < 590) { convrate = 182; config |= CFG_CR0182; } else if (val < 1850) { convrate = 1000; config |= CFG_CR1000; } else { convrate = 2700; config |= CFG_CR2700; } data->interval = convrate; data->config = config; ret = i2c_smbus_write_byte_data(data->client, LM95241_REG_RW_CONFIG, config); break; default: ret = -EOPNOTSUPP; break; } mutex_unlock(&data->update_lock); return ret; } static int lm95241_write_temp(struct device *dev, u32 attr, int channel, long val) { struct lm95241_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; int ret; mutex_lock(&data->update_lock); switch (attr) { case hwmon_temp_min: if (channel == 1) { if (val < 0) data->config |= R1DF_MASK; else data->config &= ~R1DF_MASK; } else { if (val < 0) data->config |= R2DF_MASK; else data->config &= ~R2DF_MASK; } data->valid = 0; ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); break; case hwmon_temp_max: if (channel == 1) { if (val <= 127875) data->config |= R1DF_MASK; else data->config &= ~R1DF_MASK; } else { if (val <= 127875) data->config |= R2DF_MASK; else data->config &= ~R2DF_MASK; } data->valid = 0; ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); break; case hwmon_temp_type: if (val != 1 && val != 2) { ret = -EINVAL; break; } if (channel == 1) { data->trutherm &= ~(TT_MASK << TT1_SHIFT); if (val == 1) { data->model |= R1MS_MASK; data->trutherm |= (TT_ON << TT1_SHIFT); } else { data->model &= ~R1MS_MASK; data->trutherm |= (TT_OFF << TT1_SHIFT); } } else { data->trutherm &= ~(TT_MASK << TT2_SHIFT); if (val == 1) { data->model |= R2MS_MASK; data->trutherm |= (TT_ON << TT2_SHIFT); } else { data->model &= ~R2MS_MASK; data->trutherm |= (TT_OFF << TT2_SHIFT); } } ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, data->model); if (ret < 0) break; ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, data->trutherm); break; default: ret = -EOPNOTSUPP; break; } mutex_unlock(&data->update_lock); return ret; } static int lm95241_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long val) { switch (type) { case hwmon_chip: return lm95241_write_chip(dev, attr, channel, val); case hwmon_temp: return lm95241_write_temp(dev, attr, channel, val); default: return -EOPNOTSUPP; } } static umode_t lm95241_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, int channel) { switch (type) { case hwmon_chip: switch (attr) { case hwmon_chip_update_interval: return 0644; } break; case hwmon_temp: switch (attr) { case hwmon_temp_input: return 0444; case hwmon_temp_fault: return 0444; case hwmon_temp_min: case hwmon_temp_max: case hwmon_temp_type: return 0644; } break; default: break; } return 0; } /* Return 0 if detection is successful, -ENODEV otherwise */ static int lm95241_detect(struct i2c_client *new_client, struct i2c_board_info *info) { struct i2c_adapter *adapter = new_client->adapter; const char *name; int mfg_id, chip_id; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) return -ENODEV; mfg_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID); if (mfg_id != NATSEMI_MAN_ID) return -ENODEV; chip_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID); switch (chip_id) { case LM95231_CHIP_ID: name = "lm95231"; break; case LM95241_CHIP_ID: name = "lm95241"; break; default: return -ENODEV; } /* Fill the i2c board info */ strlcpy(info->type, name, I2C_NAME_SIZE); return 0; } static void lm95241_init_client(struct i2c_client *client, struct lm95241_data *data) { data->interval = 1000; data->config = CFG_CR1000; data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT); i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER, R1FE_MASK | R2FE_MASK); i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, data->trutherm); i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, data->model); } static const struct hwmon_channel_info *lm95241_info[] = { HWMON_CHANNEL_INFO(chip, HWMON_C_UPDATE_INTERVAL), HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | HWMON_T_TYPE | HWMON_T_FAULT, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | HWMON_T_TYPE | HWMON_T_FAULT), NULL }; static const struct hwmon_ops lm95241_hwmon_ops = { .is_visible = lm95241_is_visible, .read = lm95241_read, .write = lm95241_write, }; static const struct hwmon_chip_info lm95241_chip_info = { .ops = &lm95241_hwmon_ops, .info = lm95241_info, }; static int lm95241_probe(struct i2c_client *client) { struct device *dev = &client->dev; struct lm95241_data *data; struct device *hwmon_dev; data = devm_kzalloc(dev, sizeof(struct lm95241_data), GFP_KERNEL); if (!data) return -ENOMEM; data->client = client; mutex_init(&data->update_lock); /* Initialize the LM95241 chip */ lm95241_init_client(client, data); hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data, &lm95241_chip_info, NULL); return PTR_ERR_OR_ZERO(hwmon_dev); } /* Driver data (common to all clients) */ static const struct i2c_device_id lm95241_id[] = { { "lm95231", 0 }, { "lm95241", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, lm95241_id); static struct i2c_driver lm95241_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = DEVNAME, }, .probe_new = lm95241_probe, .id_table = lm95241_id, .detect = lm95241_detect, .address_list = normal_i2c, }; module_i2c_driver(lm95241_driver); MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>"); MODULE_DESCRIPTION("LM95231/LM95241 sensor driver"); MODULE_LICENSE("GPL");