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-rw-r--r--drivers/hwmon/tmp421.c500
1 files changed, 500 insertions, 0 deletions
diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
new file mode 100644
index 0000000000..10b66c9ce0
--- /dev/null
+++ b/drivers/hwmon/tmp421.c
@@ -0,0 +1,500 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* tmp421.c
+ *
+ * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
+ * Preliminary support by:
+ * Melvin Rook, Raymond Ng
+ */
+
+/*
+ * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
+ * Supported models: TMP421, TMP422, TMP423, TMP441, TMP442
+ */
+
+#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/mutex.h>
+#include <linux/of.h>
+#include <linux/sysfs.h>
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
+ I2C_CLIENT_END };
+
+enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };
+
+#define MAX_CHANNELS 4
+/* The TMP421 registers */
+#define TMP421_STATUS_REG 0x08
+#define TMP421_CONFIG_REG_1 0x09
+#define TMP421_CONFIG_REG_2 0x0A
+#define TMP421_CONFIG_REG_REN(x) (BIT(3 + (x)))
+#define TMP421_CONFIG_REG_REN_MASK GENMASK(6, 3)
+#define TMP421_CONVERSION_RATE_REG 0x0B
+#define TMP421_N_FACTOR_REG_1 0x21
+#define TMP421_MANUFACTURER_ID_REG 0xFE
+#define TMP421_DEVICE_ID_REG 0xFF
+
+static const u8 TMP421_TEMP_MSB[MAX_CHANNELS] = { 0x00, 0x01, 0x02, 0x03 };
+static const u8 TMP421_TEMP_LSB[MAX_CHANNELS] = { 0x10, 0x11, 0x12, 0x13 };
+
+/* Flags */
+#define TMP421_CONFIG_SHUTDOWN 0x40
+#define TMP421_CONFIG_RANGE 0x04
+
+/* Manufacturer / Device ID's */
+#define TMP421_MANUFACTURER_ID 0x55
+#define TMP421_DEVICE_ID 0x21
+#define TMP422_DEVICE_ID 0x22
+#define TMP423_DEVICE_ID 0x23
+#define TMP441_DEVICE_ID 0x41
+#define TMP442_DEVICE_ID 0x42
+
+static const struct i2c_device_id tmp421_id[] = {
+ { "tmp421", 2 },
+ { "tmp422", 3 },
+ { "tmp423", 4 },
+ { "tmp441", 2 },
+ { "tmp442", 3 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tmp421_id);
+
+static const struct of_device_id __maybe_unused tmp421_of_match[] = {
+ {
+ .compatible = "ti,tmp421",
+ .data = (void *)2
+ },
+ {
+ .compatible = "ti,tmp422",
+ .data = (void *)3
+ },
+ {
+ .compatible = "ti,tmp423",
+ .data = (void *)4
+ },
+ {
+ .compatible = "ti,tmp441",
+ .data = (void *)2
+ },
+ {
+ .compatible = "ti,tmp442",
+ .data = (void *)3
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, tmp421_of_match);
+
+struct tmp421_channel {
+ const char *label;
+ bool enabled;
+ s16 temp;
+};
+
+struct tmp421_data {
+ struct i2c_client *client;
+ struct mutex update_lock;
+ u32 temp_config[MAX_CHANNELS + 1];
+ struct hwmon_channel_info temp_info;
+ const struct hwmon_channel_info *info[2];
+ struct hwmon_chip_info chip;
+ bool valid;
+ unsigned long last_updated;
+ unsigned long channels;
+ u8 config;
+ struct tmp421_channel channel[MAX_CHANNELS];
+};
+
+static int temp_from_raw(u16 reg, bool extended)
+{
+ /* Mask out status bits */
+ int temp = reg & ~0xf;
+
+ if (extended)
+ temp = temp - 64 * 256;
+ else
+ temp = (s16)temp;
+
+ return DIV_ROUND_CLOSEST(temp * 1000, 256);
+}
+
+static int tmp421_update_device(struct tmp421_data *data)
+{
+ struct i2c_client *client = data->client;
+ int ret = 0;
+ int i;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + (HZ / 2)) ||
+ !data->valid) {
+ ret = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
+ if (ret < 0)
+ goto exit;
+ data->config = ret;
+
+ for (i = 0; i < data->channels; i++) {
+ ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_MSB[i]);
+ if (ret < 0)
+ goto exit;
+ data->channel[i].temp = ret << 8;
+
+ ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_LSB[i]);
+ if (ret < 0)
+ goto exit;
+ data->channel[i].temp |= ret;
+ }
+ data->last_updated = jiffies;
+ data->valid = true;
+ }
+
+exit:
+ mutex_unlock(&data->update_lock);
+
+ if (ret < 0) {
+ data->valid = false;
+ return ret;
+ }
+
+ return 0;
+}
+
+static int tmp421_enable_channels(struct tmp421_data *data)
+{
+ int err;
+ struct i2c_client *client = data->client;
+ struct device *dev = &client->dev;
+ int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2);
+ int new, i;
+
+ if (old < 0) {
+ dev_err(dev, "error reading register, can't disable channels\n");
+ return old;
+ }
+
+ new = old & ~TMP421_CONFIG_REG_REN_MASK;
+ for (i = 0; i < data->channels; i++)
+ if (data->channel[i].enabled)
+ new |= TMP421_CONFIG_REG_REN(i);
+
+ if (new == old)
+ return 0;
+
+ err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new);
+ if (err < 0)
+ dev_err(dev, "error writing register, can't disable channels\n");
+
+ return err;
+}
+
+static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct tmp421_data *tmp421 = dev_get_drvdata(dev);
+ int ret = 0;
+
+ ret = tmp421_update_device(tmp421);
+ if (ret)
+ return ret;
+
+ switch (attr) {
+ case hwmon_temp_input:
+ if (!tmp421->channel[channel].enabled)
+ return -ENODATA;
+ *val = temp_from_raw(tmp421->channel[channel].temp,
+ tmp421->config & TMP421_CONFIG_RANGE);
+ return 0;
+ case hwmon_temp_fault:
+ if (!tmp421->channel[channel].enabled)
+ return -ENODATA;
+ /*
+ * Any of OPEN or /PVLD bits indicate a hardware mulfunction
+ * and the conversion result may be incorrect
+ */
+ *val = !!(tmp421->channel[channel].temp & 0x03);
+ return 0;
+ case hwmon_temp_enable:
+ *val = tmp421->channel[channel].enabled;
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+}
+
+static int tmp421_read_string(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, const char **str)
+{
+ struct tmp421_data *data = dev_get_drvdata(dev);
+
+ *str = data->channel[channel].label;
+
+ return 0;
+}
+
+static int tmp421_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ struct tmp421_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ switch (attr) {
+ case hwmon_temp_enable:
+ data->channel[channel].enabled = val;
+ ret = tmp421_enable_channels(data);
+ break;
+ default:
+ ret = -EOPNOTSUPP;
+ }
+
+ return ret;
+}
+
+static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ switch (attr) {
+ case hwmon_temp_fault:
+ case hwmon_temp_input:
+ return 0444;
+ case hwmon_temp_label:
+ return 0444;
+ case hwmon_temp_enable:
+ return 0644;
+ default:
+ return 0;
+ }
+}
+
+static int tmp421_init_client(struct tmp421_data *data)
+{
+ int config, config_orig;
+ struct i2c_client *client = data->client;
+
+ /* Set the conversion rate to 2 Hz */
+ i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
+
+ /* Start conversions (disable shutdown if necessary) */
+ config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
+ if (config < 0) {
+ dev_err(&client->dev,
+ "Could not read configuration register (%d)\n", config);
+ return config;
+ }
+
+ config_orig = config;
+ config &= ~TMP421_CONFIG_SHUTDOWN;
+
+ if (config != config_orig) {
+ dev_info(&client->dev, "Enable monitoring chip\n");
+ i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
+ }
+
+ return tmp421_enable_channels(data);
+}
+
+static int tmp421_detect(struct i2c_client *client,
+ struct i2c_board_info *info)
+{
+ enum chips kind;
+ struct i2c_adapter *adapter = client->adapter;
+ static const char * const names[] = {
+ "TMP421", "TMP422", "TMP423",
+ "TMP441", "TMP442"
+ };
+ int addr = client->addr;
+ u8 reg;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
+ if (reg != TMP421_MANUFACTURER_ID)
+ return -ENODEV;
+
+ reg = i2c_smbus_read_byte_data(client, TMP421_CONVERSION_RATE_REG);
+ if (reg & 0xf8)
+ return -ENODEV;
+
+ reg = i2c_smbus_read_byte_data(client, TMP421_STATUS_REG);
+ if (reg & 0x7f)
+ return -ENODEV;
+
+ reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
+ switch (reg) {
+ case TMP421_DEVICE_ID:
+ kind = tmp421;
+ break;
+ case TMP422_DEVICE_ID:
+ if (addr == 0x2a)
+ return -ENODEV;
+ kind = tmp422;
+ break;
+ case TMP423_DEVICE_ID:
+ if (addr != 0x4c && addr != 0x4d)
+ return -ENODEV;
+ kind = tmp423;
+ break;
+ case TMP441_DEVICE_ID:
+ kind = tmp441;
+ break;
+ case TMP442_DEVICE_ID:
+ if (addr != 0x4c && addr != 0x4d)
+ return -ENODEV;
+ kind = tmp442;
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ strscpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
+ dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
+ names[kind], client->addr);
+
+ return 0;
+}
+
+static int tmp421_probe_child_from_dt(struct i2c_client *client,
+ struct device_node *child,
+ struct tmp421_data *data)
+
+{
+ struct device *dev = &client->dev;
+ u32 i;
+ s32 val;
+ int err;
+
+ err = of_property_read_u32(child, "reg", &i);
+ if (err) {
+ dev_err(dev, "missing reg property of %pOFn\n", child);
+ return err;
+ }
+
+ if (i >= data->channels) {
+ dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
+ return -EINVAL;
+ }
+
+ of_property_read_string(child, "label", &data->channel[i].label);
+ if (data->channel[i].label)
+ data->temp_config[i] |= HWMON_T_LABEL;
+
+ data->channel[i].enabled = of_device_is_available(child);
+
+ err = of_property_read_s32(child, "ti,n-factor", &val);
+ if (!err) {
+ if (i == 0) {
+ dev_err(dev, "n-factor can't be set for internal channel\n");
+ return -EINVAL;
+ }
+
+ if (val > 127 || val < -128) {
+ dev_err(dev, "n-factor for channel %d invalid (%d)\n",
+ i, val);
+ return -EINVAL;
+ }
+ i2c_smbus_write_byte_data(client, TMP421_N_FACTOR_REG_1 + i - 1,
+ val);
+ }
+
+ return 0;
+}
+
+static int tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data)
+{
+ struct device *dev = &client->dev;
+ const struct device_node *np = dev->of_node;
+ struct device_node *child;
+ int err;
+
+ for_each_child_of_node(np, child) {
+ if (strcmp(child->name, "channel"))
+ continue;
+
+ err = tmp421_probe_child_from_dt(client, child, data);
+ if (err) {
+ of_node_put(child);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static const struct hwmon_ops tmp421_ops = {
+ .is_visible = tmp421_is_visible,
+ .read = tmp421_read,
+ .read_string = tmp421_read_string,
+ .write = tmp421_write,
+};
+
+static int tmp421_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct device *hwmon_dev;
+ struct tmp421_data *data;
+ int i, err;
+
+ data = devm_kzalloc(dev, sizeof(struct tmp421_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ mutex_init(&data->update_lock);
+ if (client->dev.of_node)
+ data->channels = (unsigned long)
+ of_device_get_match_data(&client->dev);
+ else
+ data->channels = i2c_match_id(tmp421_id, client)->driver_data;
+ data->client = client;
+
+ for (i = 0; i < data->channels; i++) {
+ data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_ENABLE;
+ data->channel[i].enabled = true;
+ }
+
+ err = tmp421_probe_from_dt(client, data);
+ if (err)
+ return err;
+
+ err = tmp421_init_client(data);
+ if (err)
+ return err;
+
+ data->chip.ops = &tmp421_ops;
+ data->chip.info = data->info;
+
+ data->info[0] = &data->temp_info;
+
+ data->temp_info.type = hwmon_temp;
+ data->temp_info.config = data->temp_config;
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+ data,
+ &data->chip,
+ NULL);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct i2c_driver tmp421_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "tmp421",
+ .of_match_table = of_match_ptr(tmp421_of_match),
+ },
+ .probe = tmp421_probe,
+ .id_table = tmp421_id,
+ .detect = tmp421_detect,
+ .address_list = normal_i2c,
+};
+
+module_i2c_driver(tmp421_driver);
+
+MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
+MODULE_DESCRIPTION("Texas Instruments TMP421/422/423/441/442 temperature sensor driver");
+MODULE_LICENSE("GPL");
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