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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2008, 2010 Davide Rizzo <elpa.rizzo@gmail.com>4 *5 * The LM95241 is a sensor chip made by National Semiconductors.6 * It reports up to three temperatures (its own plus up to two external ones).7 * Complete datasheet can be obtained from National's website at:8 * http://www.national.com/ds.cgi/LM/LM95241.pdf9 */10 11#include <linux/bitops.h>12#include <linux/err.h>13#include <linux/i2c.h>14#include <linux/init.h>15#include <linux/jiffies.h>16#include <linux/hwmon.h>17#include <linux/module.h>18#include <linux/mutex.h>19#include <linux/slab.h>20 21#define DEVNAME "lm95241"22 23static const unsigned short normal_i2c[] = {24 0x19, 0x2a, 0x2b, I2C_CLIENT_END };25 26/* LM95241 registers */27#define LM95241_REG_R_MAN_ID 0xFE28#define LM95241_REG_R_CHIP_ID 0xFF29#define LM95241_REG_R_STATUS 0x0230#define LM95241_REG_RW_CONFIG 0x0331#define LM95241_REG_RW_REM_FILTER 0x0632#define LM95241_REG_RW_TRUTHERM 0x0733#define LM95241_REG_W_ONE_SHOT 0x0F34#define LM95241_REG_R_LOCAL_TEMPH 0x1035#define LM95241_REG_R_REMOTE1_TEMPH 0x1136#define LM95241_REG_R_REMOTE2_TEMPH 0x1237#define LM95241_REG_R_LOCAL_TEMPL 0x2038#define LM95241_REG_R_REMOTE1_TEMPL 0x2139#define LM95241_REG_R_REMOTE2_TEMPL 0x2240#define LM95241_REG_RW_REMOTE_MODEL 0x3041 42/* LM95241 specific bitfields */43#define CFG_STOP BIT(6)44#define CFG_CR0076 0x0045#define CFG_CR0182 BIT(4)46#define CFG_CR1000 BIT(5)47#define CFG_CR2700 (BIT(4) | BIT(5))48#define CFG_CRMASK (BIT(4) | BIT(5))49#define R1MS_MASK BIT(0)50#define R2MS_MASK BIT(2)51#define R1DF_MASK BIT(1)52#define R2DF_MASK BIT(2)53#define R1FE_MASK BIT(0)54#define R2FE_MASK BIT(2)55#define R1DM BIT(0)56#define R2DM BIT(1)57#define TT1_SHIFT 058#define TT2_SHIFT 459#define TT_OFF 060#define TT_ON 161#define TT_MASK 762#define NATSEMI_MAN_ID 0x0163#define LM95231_CHIP_ID 0xA164#define LM95241_CHIP_ID 0xA465 66static const u8 lm95241_reg_address[] = {67 LM95241_REG_R_LOCAL_TEMPH,68 LM95241_REG_R_LOCAL_TEMPL,69 LM95241_REG_R_REMOTE1_TEMPH,70 LM95241_REG_R_REMOTE1_TEMPL,71 LM95241_REG_R_REMOTE2_TEMPH,72 LM95241_REG_R_REMOTE2_TEMPL73};74 75/* Client data (each client gets its own) */76struct lm95241_data {77 struct i2c_client *client;78 struct mutex update_lock;79 unsigned long last_updated; /* in jiffies */80 unsigned long interval; /* in milli-seconds */81 bool valid; /* false until following fields are valid */82 /* registers values */83 u8 temp[ARRAY_SIZE(lm95241_reg_address)];84 u8 status, config, model, trutherm;85};86 87/* Conversions */88static int temp_from_reg_signed(u8 val_h, u8 val_l)89{90 s16 val_hl = (val_h << 8) | val_l;91 return val_hl * 1000 / 256;92}93 94static int temp_from_reg_unsigned(u8 val_h, u8 val_l)95{96 u16 val_hl = (val_h << 8) | val_l;97 return val_hl * 1000 / 256;98}99 100static struct lm95241_data *lm95241_update_device(struct device *dev)101{102 struct lm95241_data *data = dev_get_drvdata(dev);103 struct i2c_client *client = data->client;104 105 mutex_lock(&data->update_lock);106 107 if (time_after(jiffies, data->last_updated108 + msecs_to_jiffies(data->interval)) ||109 !data->valid) {110 int i;111 112 dev_dbg(dev, "Updating lm95241 data.\n");113 for (i = 0; i < ARRAY_SIZE(lm95241_reg_address); i++)114 data->temp[i]115 = i2c_smbus_read_byte_data(client,116 lm95241_reg_address[i]);117 118 data->status = i2c_smbus_read_byte_data(client,119 LM95241_REG_R_STATUS);120 data->last_updated = jiffies;121 data->valid = true;122 }123 124 mutex_unlock(&data->update_lock);125 126 return data;127}128 129static int lm95241_read_chip(struct device *dev, u32 attr, int channel,130 long *val)131{132 struct lm95241_data *data = dev_get_drvdata(dev);133 134 switch (attr) {135 case hwmon_chip_update_interval:136 *val = data->interval;137 return 0;138 default:139 return -EOPNOTSUPP;140 }141}142 143static int lm95241_read_temp(struct device *dev, u32 attr, int channel,144 long *val)145{146 struct lm95241_data *data = lm95241_update_device(dev);147 148 switch (attr) {149 case hwmon_temp_input:150 if (!channel || (data->config & BIT(channel - 1)))151 *val = temp_from_reg_signed(data->temp[channel * 2],152 data->temp[channel * 2 + 1]);153 else154 *val = temp_from_reg_unsigned(data->temp[channel * 2],155 data->temp[channel * 2 + 1]);156 return 0;157 case hwmon_temp_min:158 if (channel == 1)159 *val = (data->config & R1DF_MASK) ? -128000 : 0;160 else161 *val = (data->config & R2DF_MASK) ? -128000 : 0;162 return 0;163 case hwmon_temp_max:164 if (channel == 1)165 *val = (data->config & R1DF_MASK) ? 127875 : 255875;166 else167 *val = (data->config & R2DF_MASK) ? 127875 : 255875;168 return 0;169 case hwmon_temp_type:170 if (channel == 1)171 *val = (data->model & R1MS_MASK) ? 1 : 2;172 else173 *val = (data->model & R2MS_MASK) ? 1 : 2;174 return 0;175 case hwmon_temp_fault:176 if (channel == 1)177 *val = !!(data->status & R1DM);178 else179 *val = !!(data->status & R2DM);180 return 0;181 default:182 return -EOPNOTSUPP;183 }184}185 186static int lm95241_read(struct device *dev, enum hwmon_sensor_types type,187 u32 attr, int channel, long *val)188{189 switch (type) {190 case hwmon_chip:191 return lm95241_read_chip(dev, attr, channel, val);192 case hwmon_temp:193 return lm95241_read_temp(dev, attr, channel, val);194 default:195 return -EOPNOTSUPP;196 }197}198 199static int lm95241_write_chip(struct device *dev, u32 attr, int channel,200 long val)201{202 struct lm95241_data *data = dev_get_drvdata(dev);203 int convrate;204 u8 config;205 int ret;206 207 mutex_lock(&data->update_lock);208 209 switch (attr) {210 case hwmon_chip_update_interval:211 config = data->config & ~CFG_CRMASK;212 if (val < 130) {213 convrate = 76;214 config |= CFG_CR0076;215 } else if (val < 590) {216 convrate = 182;217 config |= CFG_CR0182;218 } else if (val < 1850) {219 convrate = 1000;220 config |= CFG_CR1000;221 } else {222 convrate = 2700;223 config |= CFG_CR2700;224 }225 data->interval = convrate;226 data->config = config;227 ret = i2c_smbus_write_byte_data(data->client,228 LM95241_REG_RW_CONFIG, config);229 break;230 default:231 ret = -EOPNOTSUPP;232 break;233 }234 mutex_unlock(&data->update_lock);235 return ret;236}237 238static int lm95241_write_temp(struct device *dev, u32 attr, int channel,239 long val)240{241 struct lm95241_data *data = dev_get_drvdata(dev);242 struct i2c_client *client = data->client;243 int ret;244 245 mutex_lock(&data->update_lock);246 247 switch (attr) {248 case hwmon_temp_min:249 if (channel == 1) {250 if (val < 0)251 data->config |= R1DF_MASK;252 else253 data->config &= ~R1DF_MASK;254 } else {255 if (val < 0)256 data->config |= R2DF_MASK;257 else258 data->config &= ~R2DF_MASK;259 }260 data->valid = false;261 ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG,262 data->config);263 break;264 case hwmon_temp_max:265 if (channel == 1) {266 if (val <= 127875)267 data->config |= R1DF_MASK;268 else269 data->config &= ~R1DF_MASK;270 } else {271 if (val <= 127875)272 data->config |= R2DF_MASK;273 else274 data->config &= ~R2DF_MASK;275 }276 data->valid = false;277 ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG,278 data->config);279 break;280 case hwmon_temp_type:281 if (val != 1 && val != 2) {282 ret = -EINVAL;283 break;284 }285 if (channel == 1) {286 data->trutherm &= ~(TT_MASK << TT1_SHIFT);287 if (val == 1) {288 data->model |= R1MS_MASK;289 data->trutherm |= (TT_ON << TT1_SHIFT);290 } else {291 data->model &= ~R1MS_MASK;292 data->trutherm |= (TT_OFF << TT1_SHIFT);293 }294 } else {295 data->trutherm &= ~(TT_MASK << TT2_SHIFT);296 if (val == 1) {297 data->model |= R2MS_MASK;298 data->trutherm |= (TT_ON << TT2_SHIFT);299 } else {300 data->model &= ~R2MS_MASK;301 data->trutherm |= (TT_OFF << TT2_SHIFT);302 }303 }304 ret = i2c_smbus_write_byte_data(client,305 LM95241_REG_RW_REMOTE_MODEL,306 data->model);307 if (ret < 0)308 break;309 ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM,310 data->trutherm);311 break;312 default:313 ret = -EOPNOTSUPP;314 break;315 }316 317 mutex_unlock(&data->update_lock);318 319 return ret;320}321 322static int lm95241_write(struct device *dev, enum hwmon_sensor_types type,323 u32 attr, int channel, long val)324{325 switch (type) {326 case hwmon_chip:327 return lm95241_write_chip(dev, attr, channel, val);328 case hwmon_temp:329 return lm95241_write_temp(dev, attr, channel, val);330 default:331 return -EOPNOTSUPP;332 }333}334 335static umode_t lm95241_is_visible(const void *data,336 enum hwmon_sensor_types type,337 u32 attr, int channel)338{339 switch (type) {340 case hwmon_chip:341 switch (attr) {342 case hwmon_chip_update_interval:343 return 0644;344 }345 break;346 case hwmon_temp:347 switch (attr) {348 case hwmon_temp_input:349 return 0444;350 case hwmon_temp_fault:351 return 0444;352 case hwmon_temp_min:353 case hwmon_temp_max:354 case hwmon_temp_type:355 return 0644;356 }357 break;358 default:359 break;360 }361 return 0;362}363 364/* Return 0 if detection is successful, -ENODEV otherwise */365static int lm95241_detect(struct i2c_client *new_client,366 struct i2c_board_info *info)367{368 struct i2c_adapter *adapter = new_client->adapter;369 const char *name;370 int mfg_id, chip_id;371 372 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))373 return -ENODEV;374 375 mfg_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID);376 if (mfg_id != NATSEMI_MAN_ID)377 return -ENODEV;378 379 chip_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID);380 switch (chip_id) {381 case LM95231_CHIP_ID:382 name = "lm95231";383 break;384 case LM95241_CHIP_ID:385 name = "lm95241";386 break;387 default:388 return -ENODEV;389 }390 391 /* Fill the i2c board info */392 strscpy(info->type, name, I2C_NAME_SIZE);393 return 0;394}395 396static void lm95241_init_client(struct i2c_client *client,397 struct lm95241_data *data)398{399 data->interval = 1000;400 data->config = CFG_CR1000;401 data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT);402 403 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config);404 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER,405 R1FE_MASK | R2FE_MASK);406 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM,407 data->trutherm);408 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL,409 data->model);410}411 412static const struct hwmon_channel_info * const lm95241_info[] = {413 HWMON_CHANNEL_INFO(chip,414 HWMON_C_UPDATE_INTERVAL),415 HWMON_CHANNEL_INFO(temp,416 HWMON_T_INPUT,417 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN |418 HWMON_T_TYPE | HWMON_T_FAULT,419 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN |420 HWMON_T_TYPE | HWMON_T_FAULT),421 NULL422};423 424static const struct hwmon_ops lm95241_hwmon_ops = {425 .is_visible = lm95241_is_visible,426 .read = lm95241_read,427 .write = lm95241_write,428};429 430static const struct hwmon_chip_info lm95241_chip_info = {431 .ops = &lm95241_hwmon_ops,432 .info = lm95241_info,433};434 435static int lm95241_probe(struct i2c_client *client)436{437 struct device *dev = &client->dev;438 struct lm95241_data *data;439 struct device *hwmon_dev;440 441 data = devm_kzalloc(dev, sizeof(struct lm95241_data), GFP_KERNEL);442 if (!data)443 return -ENOMEM;444 445 data->client = client;446 mutex_init(&data->update_lock);447 448 /* Initialize the LM95241 chip */449 lm95241_init_client(client, data);450 451 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,452 data,453 &lm95241_chip_info,454 NULL);455 return PTR_ERR_OR_ZERO(hwmon_dev);456}457 458/* Driver data (common to all clients) */459static const struct i2c_device_id lm95241_id[] = {460 { "lm95231" },461 { "lm95241" },462 { }463};464MODULE_DEVICE_TABLE(i2c, lm95241_id);465 466static struct i2c_driver lm95241_driver = {467 .class = I2C_CLASS_HWMON,468 .driver = {469 .name = DEVNAME,470 },471 .probe = lm95241_probe,472 .id_table = lm95241_id,473 .detect = lm95241_detect,474 .address_list = normal_i2c,475};476 477module_i2c_driver(lm95241_driver);478 479MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>");480MODULE_DESCRIPTION("LM95231/LM95241 sensor driver");481MODULE_LICENSE("GPL");482