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-rw-r--r--drivers/hwmon/lm75.c958
1 files changed, 958 insertions, 0 deletions
diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
new file mode 100644
index 000000000..bcc3adcb3
--- /dev/null
+++ b/drivers/hwmon/lm75.c
@@ -0,0 +1,958 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * lm75.c - Part of lm_sensors, Linux kernel modules for hardware
+ * monitoring
+ * Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/util_macros.h>
+#include <linux/regulator/consumer.h>
+#include "lm75.h"
+
+/*
+ * This driver handles the LM75 and compatible digital temperature sensors.
+ */
+
+enum lm75_type { /* keep sorted in alphabetical order */
+ adt75,
+ at30ts74,
+ ds1775,
+ ds75,
+ ds7505,
+ g751,
+ lm75,
+ lm75a,
+ lm75b,
+ max6625,
+ max6626,
+ max31725,
+ mcp980x,
+ pct2075,
+ stds75,
+ stlm75,
+ tcn75,
+ tmp100,
+ tmp101,
+ tmp105,
+ tmp112,
+ tmp175,
+ tmp275,
+ tmp75,
+ tmp75b,
+ tmp75c,
+ tmp1075,
+};
+
+/**
+ * struct lm75_params - lm75 configuration parameters.
+ * @set_mask: Bits to set in configuration register when configuring
+ * the chip.
+ * @clr_mask: Bits to clear in configuration register when configuring
+ * the chip.
+ * @default_resolution: Default number of bits to represent the temperature
+ * value.
+ * @resolution_limits: Limit register resolution. Optional. Should be set if
+ * the resolution of limit registers does not match the
+ * resolution of the temperature register.
+ * @resolutions: List of resolutions associated with sample times.
+ * Optional. Should be set if num_sample_times is larger
+ * than 1, and if the resolution changes with sample times.
+ * If set, number of entries must match num_sample_times.
+ * @default_sample_time:Sample time to be set by default.
+ * @num_sample_times: Number of possible sample times to be set. Optional.
+ * Should be set if the number of sample times is larger
+ * than one.
+ * @sample_times: All the possible sample times to be set. Mandatory if
+ * num_sample_times is larger than 1. If set, number of
+ * entries must match num_sample_times.
+ */
+
+struct lm75_params {
+ u8 set_mask;
+ u8 clr_mask;
+ u8 default_resolution;
+ u8 resolution_limits;
+ const u8 *resolutions;
+ unsigned int default_sample_time;
+ u8 num_sample_times;
+ const unsigned int *sample_times;
+};
+
+/* Addresses scanned */
+static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
+ 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
+
+/* The LM75 registers */
+#define LM75_REG_TEMP 0x00
+#define LM75_REG_CONF 0x01
+#define LM75_REG_HYST 0x02
+#define LM75_REG_MAX 0x03
+#define PCT2075_REG_IDLE 0x04
+
+/* Each client has this additional data */
+struct lm75_data {
+ struct i2c_client *client;
+ struct regmap *regmap;
+ struct regulator *vs;
+ u8 orig_conf;
+ u8 current_conf;
+ u8 resolution; /* In bits, 9 to 16 */
+ unsigned int sample_time; /* In ms */
+ enum lm75_type kind;
+ const struct lm75_params *params;
+};
+
+/*-----------------------------------------------------------------------*/
+
+static const u8 lm75_sample_set_masks[] = { 0 << 5, 1 << 5, 2 << 5, 3 << 5 };
+
+#define LM75_SAMPLE_CLEAR_MASK (3 << 5)
+
+/* The structure below stores the configuration values of the supported devices.
+ * In case of being supported multiple configurations, the default one must
+ * always be the first element of the array
+ */
+static const struct lm75_params device_params[] = {
+ [adt75] = {
+ .clr_mask = 1 << 5, /* not one-shot mode */
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ },
+ [at30ts74] = {
+ .set_mask = 3 << 5, /* 12-bit mode*/
+ .default_resolution = 12,
+ .default_sample_time = 200,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 25, 50, 100, 200 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [ds1775] = {
+ .clr_mask = 3 << 5,
+ .set_mask = 2 << 5, /* 11-bit mode */
+ .default_resolution = 11,
+ .default_sample_time = 500,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 125, 250, 500, 1000 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [ds75] = {
+ .clr_mask = 3 << 5,
+ .set_mask = 2 << 5, /* 11-bit mode */
+ .default_resolution = 11,
+ .default_sample_time = 600,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [stds75] = {
+ .clr_mask = 3 << 5,
+ .set_mask = 2 << 5, /* 11-bit mode */
+ .default_resolution = 11,
+ .default_sample_time = 600,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [stlm75] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 6,
+ },
+ [ds7505] = {
+ .set_mask = 3 << 5, /* 12-bit mode*/
+ .default_resolution = 12,
+ .default_sample_time = 200,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 25, 50, 100, 200 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [g751] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ },
+ [lm75] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ },
+ [lm75a] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ },
+ [lm75b] = {
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ },
+ [max6625] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 7,
+ },
+ [max6626] = {
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 7,
+ .resolution_limits = 9,
+ },
+ [max31725] = {
+ .default_resolution = 16,
+ .default_sample_time = MSEC_PER_SEC / 20,
+ },
+ [tcn75] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 18,
+ },
+ [pct2075] = {
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ .num_sample_times = 31,
+ .sample_times = (unsigned int []){ 100, 200, 300, 400, 500, 600,
+ 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700,
+ 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,
+ 2800, 2900, 3000, 3100 },
+ },
+ [mcp980x] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode */
+ .default_resolution = 12,
+ .resolution_limits = 9,
+ .default_sample_time = 240,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 30, 60, 120, 240 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp100] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode */
+ .default_resolution = 12,
+ .default_sample_time = 320,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 40, 80, 160, 320 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp101] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode */
+ .default_resolution = 12,
+ .default_sample_time = 320,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 40, 80, 160, 320 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp105] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = 220,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 28, 55, 110, 220 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp112] = {
+ .set_mask = 3 << 5, /* 8 samples / second */
+ .clr_mask = 1 << 7, /* no one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = 125,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
+ },
+ [tmp175] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = 220,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 28, 55, 110, 220 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp275] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = 220,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 28, 55, 110, 220 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp75] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = 220,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 28, 55, 110, 220 },
+ .resolutions = (u8 []) {9, 10, 11, 12 },
+ },
+ [tmp75b] = { /* not one-shot mode, Conversion rate 37Hz */
+ .clr_mask = 1 << 7 | 3 << 5,
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 37,
+ .sample_times = (unsigned int []){ MSEC_PER_SEC / 37,
+ MSEC_PER_SEC / 18,
+ MSEC_PER_SEC / 9, MSEC_PER_SEC / 4 },
+ .num_sample_times = 4,
+ },
+ [tmp75c] = {
+ .clr_mask = 1 << 5, /*not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 12,
+ },
+ [tmp1075] = { /* not one-shot mode, 27.5 ms sample rate */
+ .clr_mask = 1 << 5 | 1 << 6 | 1 << 7,
+ .default_resolution = 12,
+ .default_sample_time = 28,
+ .num_sample_times = 4,
+ .sample_times = (unsigned int []){ 28, 55, 110, 220 },
+ }
+};
+
+static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
+{
+ return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
+}
+
+static int lm75_write_config(struct lm75_data *data, u8 set_mask,
+ u8 clr_mask)
+{
+ u8 value;
+
+ clr_mask |= LM75_SHUTDOWN;
+ value = data->current_conf & ~clr_mask;
+ value |= set_mask;
+
+ if (data->current_conf != value) {
+ s32 err;
+
+ err = i2c_smbus_write_byte_data(data->client, LM75_REG_CONF,
+ value);
+ if (err)
+ return err;
+ data->current_conf = value;
+ }
+ return 0;
+}
+
+static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct lm75_data *data = dev_get_drvdata(dev);
+ unsigned int regval;
+ int err, reg;
+
+ switch (type) {
+ case hwmon_chip:
+ switch (attr) {
+ case hwmon_chip_update_interval:
+ *val = data->sample_time;
+ break;
+ default:
+ return -EINVAL;
+ }
+ break;
+ case hwmon_temp:
+ switch (attr) {
+ case hwmon_temp_input:
+ reg = LM75_REG_TEMP;
+ break;
+ case hwmon_temp_max:
+ reg = LM75_REG_MAX;
+ break;
+ case hwmon_temp_max_hyst:
+ reg = LM75_REG_HYST;
+ break;
+ default:
+ return -EINVAL;
+ }
+ err = regmap_read(data->regmap, reg, &regval);
+ if (err < 0)
+ return err;
+
+ *val = lm75_reg_to_mc(regval, data->resolution);
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int lm75_write_temp(struct device *dev, u32 attr, long temp)
+{
+ struct lm75_data *data = dev_get_drvdata(dev);
+ u8 resolution;
+ int reg;
+
+ switch (attr) {
+ case hwmon_temp_max:
+ reg = LM75_REG_MAX;
+ break;
+ case hwmon_temp_max_hyst:
+ reg = LM75_REG_HYST;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /*
+ * Resolution of limit registers is assumed to be the same as the
+ * temperature input register resolution unless given explicitly.
+ */
+ if (data->params->resolution_limits)
+ resolution = data->params->resolution_limits;
+ else
+ resolution = data->resolution;
+
+ temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
+ temp = DIV_ROUND_CLOSEST(temp << (resolution - 8),
+ 1000) << (16 - resolution);
+
+ return regmap_write(data->regmap, reg, (u16)temp);
+}
+
+static int lm75_update_interval(struct device *dev, long val)
+{
+ struct lm75_data *data = dev_get_drvdata(dev);
+ unsigned int reg;
+ u8 index;
+ s32 err;
+
+ index = find_closest(val, data->params->sample_times,
+ (int)data->params->num_sample_times);
+
+ switch (data->kind) {
+ default:
+ err = lm75_write_config(data, lm75_sample_set_masks[index],
+ LM75_SAMPLE_CLEAR_MASK);
+ if (err)
+ return err;
+
+ data->sample_time = data->params->sample_times[index];
+ if (data->params->resolutions)
+ data->resolution = data->params->resolutions[index];
+ break;
+ case tmp112:
+ err = regmap_read(data->regmap, LM75_REG_CONF, &reg);
+ if (err < 0)
+ return err;
+ reg &= ~0x00c0;
+ reg |= (3 - index) << 6;
+ err = regmap_write(data->regmap, LM75_REG_CONF, reg);
+ if (err < 0)
+ return err;
+ data->sample_time = data->params->sample_times[index];
+ break;
+ case pct2075:
+ err = i2c_smbus_write_byte_data(data->client, PCT2075_REG_IDLE,
+ index + 1);
+ if (err)
+ return err;
+ data->sample_time = data->params->sample_times[index];
+ break;
+ }
+ return 0;
+}
+
+static int lm75_write_chip(struct device *dev, u32 attr, long val)
+{
+ switch (attr) {
+ case hwmon_chip_update_interval:
+ return lm75_update_interval(dev, val);
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ switch (type) {
+ case hwmon_chip:
+ return lm75_write_chip(dev, attr, val);
+ case hwmon_temp:
+ return lm75_write_temp(dev, attr, val);
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static umode_t lm75_is_visible(const void *data, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ const struct lm75_data *config_data = data;
+
+ switch (type) {
+ case hwmon_chip:
+ switch (attr) {
+ case hwmon_chip_update_interval:
+ if (config_data->params->num_sample_times > 1)
+ return 0644;
+ return 0444;
+ }
+ break;
+ case hwmon_temp:
+ switch (attr) {
+ case hwmon_temp_input:
+ return 0444;
+ case hwmon_temp_max:
+ case hwmon_temp_max_hyst:
+ return 0644;
+ }
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+static const struct hwmon_channel_info *lm75_info[] = {
+ HWMON_CHANNEL_INFO(chip,
+ HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL),
+ HWMON_CHANNEL_INFO(temp,
+ HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
+ NULL
+};
+
+static const struct hwmon_ops lm75_hwmon_ops = {
+ .is_visible = lm75_is_visible,
+ .read = lm75_read,
+ .write = lm75_write,
+};
+
+static const struct hwmon_chip_info lm75_chip_info = {
+ .ops = &lm75_hwmon_ops,
+ .info = lm75_info,
+};
+
+static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+ return reg != LM75_REG_TEMP;
+}
+
+static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+ return reg == LM75_REG_TEMP || reg == LM75_REG_CONF;
+}
+
+static const struct regmap_config lm75_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 16,
+ .max_register = PCT2075_REG_IDLE,
+ .writeable_reg = lm75_is_writeable_reg,
+ .volatile_reg = lm75_is_volatile_reg,
+ .val_format_endian = REGMAP_ENDIAN_BIG,
+ .cache_type = REGCACHE_RBTREE,
+ .use_single_read = true,
+ .use_single_write = true,
+};
+
+static void lm75_disable_regulator(void *data)
+{
+ struct lm75_data *lm75 = data;
+
+ regulator_disable(lm75->vs);
+}
+
+static void lm75_remove(void *data)
+{
+ struct lm75_data *lm75 = data;
+ struct i2c_client *client = lm75->client;
+
+ i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
+}
+
+static const struct i2c_device_id lm75_ids[];
+
+static int lm75_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct device *hwmon_dev;
+ struct lm75_data *data;
+ int status, err;
+ enum lm75_type kind;
+
+ if (client->dev.of_node)
+ kind = (enum lm75_type)of_device_get_match_data(&client->dev);
+ else
+ kind = i2c_match_id(lm75_ids, client)->driver_data;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
+ return -EIO;
+
+ data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->client = client;
+ data->kind = kind;
+
+ data->vs = devm_regulator_get(dev, "vs");
+ if (IS_ERR(data->vs))
+ return PTR_ERR(data->vs);
+
+ data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
+ if (IS_ERR(data->regmap))
+ return PTR_ERR(data->regmap);
+
+ /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
+ * Then tweak to be more precise when appropriate.
+ */
+
+ data->params = &device_params[data->kind];
+
+ /* Save default sample time and resolution*/
+ data->sample_time = data->params->default_sample_time;
+ data->resolution = data->params->default_resolution;
+
+ /* Enable the power */
+ err = regulator_enable(data->vs);
+ if (err) {
+ dev_err(dev, "failed to enable regulator: %d\n", err);
+ return err;
+ }
+
+ err = devm_add_action_or_reset(dev, lm75_disable_regulator, data);
+ if (err)
+ return err;
+
+ /* Cache original configuration */
+ status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
+ if (status < 0) {
+ dev_dbg(dev, "Can't read config? %d\n", status);
+ return status;
+ }
+ data->orig_conf = status;
+ data->current_conf = status;
+
+ err = lm75_write_config(data, data->params->set_mask,
+ data->params->clr_mask);
+ if (err)
+ return err;
+
+ err = devm_add_action_or_reset(dev, lm75_remove, data);
+ if (err)
+ return err;
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+ data, &lm75_chip_info,
+ NULL);
+ if (IS_ERR(hwmon_dev))
+ return PTR_ERR(hwmon_dev);
+
+ dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
+
+ return 0;
+}
+
+static const struct i2c_device_id lm75_ids[] = {
+ { "adt75", adt75, },
+ { "at30ts74", at30ts74, },
+ { "ds1775", ds1775, },
+ { "ds75", ds75, },
+ { "ds7505", ds7505, },
+ { "g751", g751, },
+ { "lm75", lm75, },
+ { "lm75a", lm75a, },
+ { "lm75b", lm75b, },
+ { "max6625", max6625, },
+ { "max6626", max6626, },
+ { "max31725", max31725, },
+ { "max31726", max31725, },
+ { "mcp980x", mcp980x, },
+ { "pct2075", pct2075, },
+ { "stds75", stds75, },
+ { "stlm75", stlm75, },
+ { "tcn75", tcn75, },
+ { "tmp100", tmp100, },
+ { "tmp101", tmp101, },
+ { "tmp105", tmp105, },
+ { "tmp112", tmp112, },
+ { "tmp175", tmp175, },
+ { "tmp275", tmp275, },
+ { "tmp75", tmp75, },
+ { "tmp75b", tmp75b, },
+ { "tmp75c", tmp75c, },
+ { "tmp1075", tmp1075, },
+ { /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i2c, lm75_ids);
+
+static const struct of_device_id __maybe_unused lm75_of_match[] = {
+ {
+ .compatible = "adi,adt75",
+ .data = (void *)adt75
+ },
+ {
+ .compatible = "atmel,at30ts74",
+ .data = (void *)at30ts74
+ },
+ {
+ .compatible = "dallas,ds1775",
+ .data = (void *)ds1775
+ },
+ {
+ .compatible = "dallas,ds75",
+ .data = (void *)ds75
+ },
+ {
+ .compatible = "dallas,ds7505",
+ .data = (void *)ds7505
+ },
+ {
+ .compatible = "gmt,g751",
+ .data = (void *)g751
+ },
+ {
+ .compatible = "national,lm75",
+ .data = (void *)lm75
+ },
+ {
+ .compatible = "national,lm75a",
+ .data = (void *)lm75a
+ },
+ {
+ .compatible = "national,lm75b",
+ .data = (void *)lm75b
+ },
+ {
+ .compatible = "maxim,max6625",
+ .data = (void *)max6625
+ },
+ {
+ .compatible = "maxim,max6626",
+ .data = (void *)max6626
+ },
+ {
+ .compatible = "maxim,max31725",
+ .data = (void *)max31725
+ },
+ {
+ .compatible = "maxim,max31726",
+ .data = (void *)max31725
+ },
+ {
+ .compatible = "maxim,mcp980x",
+ .data = (void *)mcp980x
+ },
+ {
+ .compatible = "nxp,pct2075",
+ .data = (void *)pct2075
+ },
+ {
+ .compatible = "st,stds75",
+ .data = (void *)stds75
+ },
+ {
+ .compatible = "st,stlm75",
+ .data = (void *)stlm75
+ },
+ {
+ .compatible = "microchip,tcn75",
+ .data = (void *)tcn75
+ },
+ {
+ .compatible = "ti,tmp100",
+ .data = (void *)tmp100
+ },
+ {
+ .compatible = "ti,tmp101",
+ .data = (void *)tmp101
+ },
+ {
+ .compatible = "ti,tmp105",
+ .data = (void *)tmp105
+ },
+ {
+ .compatible = "ti,tmp112",
+ .data = (void *)tmp112
+ },
+ {
+ .compatible = "ti,tmp175",
+ .data = (void *)tmp175
+ },
+ {
+ .compatible = "ti,tmp275",
+ .data = (void *)tmp275
+ },
+ {
+ .compatible = "ti,tmp75",
+ .data = (void *)tmp75
+ },
+ {
+ .compatible = "ti,tmp75b",
+ .data = (void *)tmp75b
+ },
+ {
+ .compatible = "ti,tmp75c",
+ .data = (void *)tmp75c
+ },
+ {
+ .compatible = "ti,tmp1075",
+ .data = (void *)tmp1075
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, lm75_of_match);
+
+#define LM75A_ID 0xA1
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int lm75_detect(struct i2c_client *new_client,
+ struct i2c_board_info *info)
+{
+ struct i2c_adapter *adapter = new_client->adapter;
+ int i;
+ int conf, hyst, os;
+ bool is_lm75a = 0;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA))
+ return -ENODEV;
+
+ /*
+ * Now, we do the remaining detection. There is no identification-
+ * dedicated register so we have to rely on several tricks:
+ * unused bits, registers cycling over 8-address boundaries,
+ * addresses 0x04-0x07 returning the last read value.
+ * The cycling+unused addresses combination is not tested,
+ * since it would significantly slow the detection down and would
+ * hardly add any value.
+ *
+ * The National Semiconductor LM75A is different than earlier
+ * LM75s. It has an ID byte of 0xaX (where X is the chip
+ * revision, with 1 being the only revision in existence) in
+ * register 7, and unused registers return 0xff rather than the
+ * last read value.
+ *
+ * Note that this function only detects the original National
+ * Semiconductor LM75 and the LM75A. Clones from other vendors
+ * aren't detected, on purpose, because they are typically never
+ * found on PC hardware. They are found on embedded designs where
+ * they can be instantiated explicitly so detection is not needed.
+ * The absence of identification registers on all these clones
+ * would make their exhaustive detection very difficult and weak,
+ * and odds are that the driver would bind to unsupported devices.
+ */
+
+ /* Unused bits */
+ conf = i2c_smbus_read_byte_data(new_client, 1);
+ if (conf & 0xe0)
+ return -ENODEV;
+
+ /* First check for LM75A */
+ if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
+ /*
+ * LM75A returns 0xff on unused registers so
+ * just to be sure we check for that too.
+ */
+ if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
+ || i2c_smbus_read_byte_data(new_client, 5) != 0xff
+ || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
+ return -ENODEV;
+ is_lm75a = 1;
+ hyst = i2c_smbus_read_byte_data(new_client, 2);
+ os = i2c_smbus_read_byte_data(new_client, 3);
+ } else { /* Traditional style LM75 detection */
+ /* Unused addresses */
+ hyst = i2c_smbus_read_byte_data(new_client, 2);
+ if (i2c_smbus_read_byte_data(new_client, 4) != hyst
+ || i2c_smbus_read_byte_data(new_client, 5) != hyst
+ || i2c_smbus_read_byte_data(new_client, 6) != hyst
+ || i2c_smbus_read_byte_data(new_client, 7) != hyst)
+ return -ENODEV;
+ os = i2c_smbus_read_byte_data(new_client, 3);
+ if (i2c_smbus_read_byte_data(new_client, 4) != os
+ || i2c_smbus_read_byte_data(new_client, 5) != os
+ || i2c_smbus_read_byte_data(new_client, 6) != os
+ || i2c_smbus_read_byte_data(new_client, 7) != os)
+ return -ENODEV;
+ }
+ /*
+ * It is very unlikely that this is a LM75 if both
+ * hysteresis and temperature limit registers are 0.
+ */
+ if (hyst == 0 && os == 0)
+ return -ENODEV;
+
+ /* Addresses cycling */
+ for (i = 8; i <= 248; i += 40) {
+ if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
+ || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
+ || i2c_smbus_read_byte_data(new_client, i + 3) != os)
+ return -ENODEV;
+ if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
+ != LM75A_ID)
+ return -ENODEV;
+ }
+
+ strscpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int lm75_suspend(struct device *dev)
+{
+ int status;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
+ if (status < 0) {
+ dev_dbg(&client->dev, "Can't read config? %d\n", status);
+ return status;
+ }
+ status = status | LM75_SHUTDOWN;
+ i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
+ return 0;
+}
+
+static int lm75_resume(struct device *dev)
+{
+ int status;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
+ if (status < 0) {
+ dev_dbg(&client->dev, "Can't read config? %d\n", status);
+ return status;
+ }
+ status = status & ~LM75_SHUTDOWN;
+ i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
+ return 0;
+}
+
+static const struct dev_pm_ops lm75_dev_pm_ops = {
+ .suspend = lm75_suspend,
+ .resume = lm75_resume,
+};
+#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
+#else
+#define LM75_DEV_PM_OPS NULL
+#endif /* CONFIG_PM */
+
+static struct i2c_driver lm75_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "lm75",
+ .of_match_table = of_match_ptr(lm75_of_match),
+ .pm = LM75_DEV_PM_OPS,
+ },
+ .probe_new = lm75_probe,
+ .id_table = lm75_ids,
+ .detect = lm75_detect,
+ .address_list = normal_i2c,
+};
+
+module_i2c_driver(lm75_driver);
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
+MODULE_DESCRIPTION("LM75 driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 08:50:21 +0000