]> git.ipfire.org Git - thirdparty/kernel/linux.git/commitdiff
hwmon: Add driver for Texas Instruments TMP464 and TMP468
authorGuenter Roeck <linux@roeck-us.net>
Tue, 22 Feb 2022 22:36:10 +0000 (14:36 -0800)
committerGuenter Roeck <linux@roeck-us.net>
Thu, 3 Mar 2022 15:40:42 +0000 (07:40 -0800)
Add support for Texas Instruments TMP464 and TMP468 temperature sensor
ICs.

TI's TMP464 is an I2C temperature sensor chip. This chip is similar
to TI's TMP421 chip, but with 16bit-wide registers (instead of
8bit-wide registers). The chip has one local sensor and four remote
sensors. TMP468 is similar to TMP464 but has one local and eight
remote sensors.

Originally-from: Agathe Porte <agathe.porte@nokia.com>
Cc: Agathe Porte <agathe.porte@nokia.com>
Cc: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Tested-by: Agathe Porte <agathe.porte@nokia.com>
Link: https://lore.kernel.org/r/20220222223610.23098-2-linux@roeck-us.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Documentation/hwmon/index.rst
Documentation/hwmon/tmp464.rst [new file with mode: 0644]
MAINTAINERS
drivers/hwmon/Kconfig
drivers/hwmon/Makefile
drivers/hwmon/tmp464.c [new file with mode: 0644]

index 075d1defcd204a3d01acd42b93ef21014aa334fa..9d2787a12a69371593e57201fbb65cd3596918f5 100644 (file)
@@ -195,6 +195,7 @@ Hardware Monitoring Kernel Drivers
    tmp108
    tmp401
    tmp421
+   tmp464
    tmp513
    tps23861
    tps40422
diff --git a/Documentation/hwmon/tmp464.rst b/Documentation/hwmon/tmp464.rst
new file mode 100644 (file)
index 0000000..7596e76
--- /dev/null
@@ -0,0 +1,73 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver tmp464
+====================
+
+Supported chips:
+
+  * Texas Instruments TMP464
+
+    Prefix: 'tmp464'
+
+    Addresses scanned: I2C 0x48, 0x49, 0x4a and 0x4b
+
+    Datasheet: http://focus.ti.com/docs/prod/folders/print/tmp464.html
+
+  * Texas Instruments TMP468
+
+    Prefix: 'tmp468'
+
+    Addresses scanned: I2C 0x48, 0x49, 0x4a and 0x4b
+
+    Datasheet: http://focus.ti.com/docs/prod/folders/print/tmp468.html
+
+Authors:
+
+       Agathe Porte <agathe.porte@nokia.com>
+       Guenter Roeck <linux@roeck-us.net>
+
+Description
+-----------
+
+This driver implements support for Texas Instruments TMP464 and TMP468
+temperature sensor chips. TMP464 provides one local and four remote
+sensors. TMP468 provides one local and eight remote sensors.
+Temperature is measured in degrees Celsius. The chips are wired over
+I2C/SMBus and specified over a temperature range of -40 to +125 degrees
+Celsius. Resolution for both the local and remote channels is 0.0625
+degree C.
+
+The chips support only temperature measurements. The driver exports
+temperature values, limits, and alarms via the following sysfs files:
+
+**temp[1-9]_input**
+
+**temp[1-9]_max**
+
+**temp[1-9]_max_hyst**
+
+**temp[1-9]_max_alarm**
+
+**temp[1-9]_crit**
+
+**temp[1-9]_crit_alarm**
+
+**temp[1-9]_crit_hyst**
+
+**temp[2-9]_offset**
+
+**temp[2-9]_fault**
+
+Each sensor can be individually disabled via Devicetree or from sysfs
+via:
+
+**temp[1-9]_enable**
+
+If labels were specified in Devicetree, additional sysfs files will
+be present:
+
+**temp[1-9]_label**
+
+The update interval is configurable with the following sysfs attribute.
+
+**update_interval**
index 3766875f4f2aeea40a365aa7aa671fcbb4e9ea99..a9c9ee378f93e98dcf52d7f18334773ae3d3bad2 100644 (file)
@@ -19502,6 +19502,8 @@ M:      Guenter Roeck <linux@roeck-us.net>
 L:     linux-hwmon@vger.kernel.org
 S:     Maintained
 F:     Documentation/devicetree/bindings/hwmon/ti,tmp464.yaml
+F:     Documentation/hwmon/tmp464.rst
+F:     drivers/hwmon/tmp464.c
 
 TMP513 HARDWARE MONITOR DRIVER
 M:     Eric Tremblay <etremblay@distech-controls.com>
index 463d5b110a85f90e540eacbbef368f27dd6df5ae..9ab4e9b3d27b6a57f76b3f9817d3534d5eb6888a 100644 (file)
@@ -1996,6 +1996,17 @@ config SENSORS_TMP421
          This driver can also be built as a module. If so, the module
          will be called tmp421.
 
+config SENSORS_TMP464
+       tristate "Texas Instruments TMP464 and compatible"
+       depends on I2C
+       select REGMAP_I2C
+       help
+         If you say yes here you get support for Texas Instruments TMP464
+         and TMP468 temperature sensor chips.
+
+         This driver can also be built as a module. If so, the module
+         will be called tmp464.
+
 config SENSORS_TMP513
        tristate "Texas Instruments TMP513 and compatibles"
        depends on I2C
index 7bba3415ca3df9607eb0176c418d7bfc29e2b89a..4ed138d0621f991bbd0b19005d728b134557c3e7 100644 (file)
@@ -195,6 +195,7 @@ obj-$(CONFIG_SENSORS_TMP103)        += tmp103.o
 obj-$(CONFIG_SENSORS_TMP108)   += tmp108.o
 obj-$(CONFIG_SENSORS_TMP401)   += tmp401.o
 obj-$(CONFIG_SENSORS_TMP421)   += tmp421.o
+obj-$(CONFIG_SENSORS_TMP464)   += tmp464.o
 obj-$(CONFIG_SENSORS_TMP513)   += tmp513.o
 obj-$(CONFIG_SENSORS_VEXPRESS) += vexpress-hwmon.o
 obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
diff --git a/drivers/hwmon/tmp464.c b/drivers/hwmon/tmp464.c
new file mode 100644 (file)
index 0000000..7814f39
--- /dev/null
@@ -0,0 +1,712 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/* Driver for the Texas Instruments TMP464 SMBus temperature sensor IC.
+ * Supported models: TMP464, TMP468
+
+ * Copyright (C) 2022 Agathe Porte <agathe.porte@nokia.com>
+ * Preliminary support by:
+ * Lionel Pouliquen <lionel.lp.pouliquen@nokia.com>
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, I2C_CLIENT_END };
+
+#define TMP464_NUM_CHANNELS            5       /* chan 0 is internal, 1-4 are remote */
+#define TMP468_NUM_CHANNELS            9       /* chan 0 is internal, 1-8 are remote */
+
+#define MAX_CHANNELS                   9
+
+#define TMP464_TEMP_REG(channel)       (channel)
+#define TMP464_TEMP_OFFSET_REG(channel)        (0x40 + ((channel) - 1) * 8)
+#define TMP464_N_FACTOR_REG(channel)   (0x41 + ((channel) - 1) * 8)
+
+static const u8 TMP464_THERM_LIMIT[MAX_CHANNELS] = {
+       0x39, 0x42, 0x4A, 0x52, 0x5A, 0x62, 0x6a, 0x72, 0x7a };
+static const u8 TMP464_THERM2_LIMIT[MAX_CHANNELS] = {
+       0x3A, 0x43, 0x4B, 0x53, 0x5B, 0x63, 0x6b, 0x73, 0x7b };
+
+#define TMP464_THERM_STATUS_REG                        0x21
+#define TMP464_THERM2_STATUS_REG               0x22
+#define TMP464_REMOTE_OPEN_REG                 0x23
+#define TMP464_CONFIG_REG                      0x30
+#define TMP464_TEMP_HYST_REG                   0x38
+#define TMP464_LOCK_REG                                0xc4
+
+/* Identification */
+#define TMP464_MANUFACTURER_ID_REG             0xFE
+#define TMP464_DEVICE_ID_REG                   0xFF
+
+/* Flags */
+#define TMP464_CONFIG_SHUTDOWN                 BIT(5)
+#define TMP464_CONFIG_RANGE                    0x04
+#define TMP464_CONFIG_REG_REN(x)               (BIT(7 + (x)))
+#define TMP464_CONFIG_REG_REN_MASK             GENMASK(15, 7)
+#define TMP464_CONFIG_CONVERSION_RATE_B0       2
+#define TMP464_CONFIG_CONVERSION_RATE_B2       4
+#define TMP464_CONFIG_CONVERSION_RATE_MASK      GENMASK(TMP464_CONFIG_CONVERSION_RATE_B2, \
+                                                       TMP464_CONFIG_CONVERSION_RATE_B0)
+
+#define TMP464_UNLOCK_VAL                      0xeb19
+#define TMP464_LOCK_VAL                                0x5ca6
+#define TMP464_LOCKED                          0x8000
+
+/* Manufacturer / Device ID's */
+#define TMP464_MANUFACTURER_ID                 0x5449
+#define TMP464_DEVICE_ID                       0x1468
+#define TMP468_DEVICE_ID                       0x0468
+
+static const struct i2c_device_id tmp464_id[] = {
+       { "tmp464", TMP464_NUM_CHANNELS },
+       { "tmp468", TMP468_NUM_CHANNELS },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, tmp464_id);
+
+static const struct of_device_id __maybe_unused tmp464_of_match[] = {
+       {
+               .compatible = "ti,tmp464",
+               .data = (void *)TMP464_NUM_CHANNELS
+       },
+       {
+               .compatible = "ti,tmp468",
+               .data = (void *)TMP468_NUM_CHANNELS
+       },
+       {},
+};
+MODULE_DEVICE_TABLE(of, tmp464_of_match);
+
+struct tmp464_channel {
+       const char *label;
+       bool enabled;
+};
+
+struct tmp464_data {
+       struct regmap *regmap;
+       struct mutex update_lock;
+       int channels;
+       s16 config_orig;
+       u16 open_reg;
+       unsigned long last_updated;
+       bool valid;
+       int update_interval;
+       struct tmp464_channel channel[MAX_CHANNELS];
+};
+
+static int temp_from_reg(s16 reg)
+{
+       return DIV_ROUND_CLOSEST((reg >> 3) * 625, 10);
+}
+
+static s16 temp_to_limit_reg(long temp)
+{
+       return DIV_ROUND_CLOSEST(temp, 500) << 6;
+}
+
+static s16 temp_to_offset_reg(long temp)
+{
+       return DIV_ROUND_CLOSEST(temp * 10, 625) << 3;
+}
+
+static int tmp464_enable_channels(struct tmp464_data *data)
+{
+       struct regmap *regmap = data->regmap;
+       u16 enable = 0;
+       int i;
+
+       for (i = 0; i < data->channels; i++)
+               if (data->channel[i].enabled)
+                       enable |= TMP464_CONFIG_REG_REN(i);
+
+       return regmap_update_bits(regmap, TMP464_CONFIG_REG, TMP464_CONFIG_REG_REN_MASK, enable);
+}
+
+static int tmp464_chip_read(struct device *dev, u32 attr, int channel, long *val)
+{
+       struct tmp464_data *data = dev_get_drvdata(dev);
+
+       switch (attr) {
+       case hwmon_chip_update_interval:
+               *val = data->update_interval;
+               return 0;
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int tmp464_temp_read(struct device *dev, u32 attr, int channel, long *val)
+{
+       struct tmp464_data *data = dev_get_drvdata(dev);
+       struct regmap *regmap = data->regmap;
+       unsigned int regval, regval2;
+       int err = 0;
+
+       mutex_lock(&data->update_lock);
+
+       switch (attr) {
+       case hwmon_temp_max_alarm:
+               err = regmap_read(regmap, TMP464_THERM_STATUS_REG, &regval);
+               if (err < 0)
+                       break;
+               *val = !!(regval & BIT(channel + 7));
+               break;
+       case hwmon_temp_crit_alarm:
+               err = regmap_read(regmap, TMP464_THERM2_STATUS_REG, &regval);
+               if (err < 0)
+                       break;
+               *val = !!(regval & BIT(channel + 7));
+               break;
+       case hwmon_temp_fault:
+               /*
+                * The chip clears TMP464_REMOTE_OPEN_REG after it is read
+                * and only updates it after the next measurement cycle is
+                * complete. That means we have to cache the value internally
+                * for one measurement cycle and report the cached value.
+                */
+               if (!data->valid || time_after(jiffies, data->last_updated +
+                                              msecs_to_jiffies(data->update_interval))) {
+                       err = regmap_read(regmap, TMP464_REMOTE_OPEN_REG, &regval);
+                       if (err < 0)
+                               break;
+                       data->open_reg = regval;
+                       data->last_updated = jiffies;
+                       data->valid = true;
+               }
+               *val = !!(data->open_reg & BIT(channel + 7));
+               break;
+       case hwmon_temp_max_hyst:
+               err = regmap_read(regmap, TMP464_THERM_LIMIT[channel], &regval);
+               if (err < 0)
+                       break;
+               err = regmap_read(regmap, TMP464_TEMP_HYST_REG, &regval2);
+               if (err < 0)
+                       break;
+               regval -= regval2;
+               *val = temp_from_reg(regval);
+               break;
+       case hwmon_temp_max:
+               err = regmap_read(regmap, TMP464_THERM_LIMIT[channel], &regval);
+               if (err < 0)
+                       break;
+               *val = temp_from_reg(regval);
+               break;
+       case hwmon_temp_crit_hyst:
+               err = regmap_read(regmap, TMP464_THERM2_LIMIT[channel], &regval);
+               if (err < 0)
+                       break;
+               err = regmap_read(regmap, TMP464_TEMP_HYST_REG, &regval2);
+               if (err < 0)
+                       break;
+               regval -= regval2;
+               *val = temp_from_reg(regval);
+               break;
+       case hwmon_temp_crit:
+               err = regmap_read(regmap, TMP464_THERM2_LIMIT[channel], &regval);
+               if (err < 0)
+                       break;
+               *val = temp_from_reg(regval);
+               break;
+       case hwmon_temp_offset:
+               err = regmap_read(regmap, TMP464_TEMP_OFFSET_REG(channel), &regval);
+               if (err < 0)
+                       break;
+               *val = temp_from_reg(regval);
+               break;
+       case hwmon_temp_input:
+               if (!data->channel[channel].enabled) {
+                       err = -ENODATA;
+                       break;
+               }
+               err = regmap_read(regmap, TMP464_TEMP_REG(channel), &regval);
+               if (err < 0)
+                       break;
+               *val = temp_from_reg(regval);
+               break;
+       case hwmon_temp_enable:
+               *val = data->channel[channel].enabled;
+               break;
+       default:
+               err = -EOPNOTSUPP;
+               break;
+       }
+
+       mutex_unlock(&data->update_lock);
+
+       return err;
+}
+
+static int tmp464_read(struct device *dev, enum hwmon_sensor_types type,
+                      u32 attr, int channel, long *val)
+{
+       switch (type) {
+       case hwmon_chip:
+               return tmp464_chip_read(dev, attr, channel, val);
+       case hwmon_temp:
+               return tmp464_temp_read(dev, attr, channel, val);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int tmp464_read_string(struct device *dev, enum hwmon_sensor_types type,
+                             u32 attr, int channel, const char **str)
+{
+       struct tmp464_data *data = dev_get_drvdata(dev);
+
+       *str = data->channel[channel].label;
+
+       return 0;
+}
+
+static int tmp464_set_convrate(struct tmp464_data *data, long interval)
+{
+       int rate;
+
+       /*
+        * For valid rates, interval in milli-seconds can be calculated as
+        *      interval = 125 << (7 - rate);
+        * or
+        *      interval = (1 << (7 - rate)) * 125;
+        * The rate is therefore
+        *      rate = 7 - __fls(interval / 125);
+        * and the rounded rate is
+        *      rate = 7 - __fls(interval * 4 / (125 * 3));
+        * Use clamp_val() to avoid overflows, and to ensure valid input
+        * for __fls.
+        */
+       interval = clamp_val(interval, 125, 16000);
+       rate = 7 - __fls(interval * 4 / (125 * 3));
+       data->update_interval = 125 << (7 - rate);
+
+       return regmap_update_bits(data->regmap, TMP464_CONFIG_REG,
+                                 TMP464_CONFIG_CONVERSION_RATE_MASK,
+                                 rate << TMP464_CONFIG_CONVERSION_RATE_B0);
+}
+
+static int tmp464_chip_write(struct tmp464_data *data, u32 attr, int channel, long val)
+{
+       switch (attr) {
+       case hwmon_chip_update_interval:
+               return tmp464_set_convrate(data, val);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int tmp464_temp_write(struct tmp464_data *data, u32 attr, int channel, long val)
+{
+       struct regmap *regmap = data->regmap;
+       unsigned int regval;
+       int err = 0;
+
+       switch (attr) {
+       case hwmon_temp_max_hyst:
+               err = regmap_read(regmap, TMP464_THERM_LIMIT[0], &regval);
+               if (err < 0)
+                       break;
+               val = clamp_val(val, -256000, 256000);  /* prevent overflow/underflow */
+               val = clamp_val(temp_from_reg(regval) - val, 0, 255000);
+               err = regmap_write(regmap, TMP464_TEMP_HYST_REG,
+                                  DIV_ROUND_CLOSEST(val, 1000) << 7);
+               break;
+       case hwmon_temp_max:
+               val = temp_to_limit_reg(clamp_val(val, -255000, 255500));
+               err = regmap_write(regmap, TMP464_THERM_LIMIT[channel], val);
+               break;
+       case hwmon_temp_crit:
+               val = temp_to_limit_reg(clamp_val(val, -255000, 255500));
+               err = regmap_write(regmap, TMP464_THERM2_LIMIT[channel], val);
+               break;
+       case hwmon_temp_offset:
+               val = temp_to_offset_reg(clamp_val(val, -128000, 127937));
+               err = regmap_write(regmap, TMP464_TEMP_OFFSET_REG(channel), val);
+               break;
+       case hwmon_temp_enable:
+               data->channel[channel].enabled = !!val;
+               err = tmp464_enable_channels(data);
+               break;
+       default:
+               err = -EOPNOTSUPP;
+               break;
+       }
+
+       return err;
+}
+
+static int tmp464_write(struct device *dev, enum hwmon_sensor_types type,
+                       u32 attr, int channel, long val)
+{
+       struct tmp464_data *data = dev_get_drvdata(dev);
+       int err;
+
+       mutex_lock(&data->update_lock);
+
+       switch (type) {
+       case hwmon_chip:
+               err = tmp464_chip_write(data, attr, channel, val);
+               break;
+       case hwmon_temp:
+               err = tmp464_temp_write(data, attr, channel, val);
+               break;
+       default:
+               err = -EOPNOTSUPP;
+               break;
+       }
+
+       mutex_unlock(&data->update_lock);
+
+       return err;
+}
+
+static umode_t tmp464_is_visible(const void *_data, enum hwmon_sensor_types type,
+                                u32 attr, int channel)
+{
+       const struct tmp464_data *data = _data;
+
+       if (channel >= data->channels)
+               return 0;
+
+       if (type == hwmon_chip) {
+               if (attr == hwmon_chip_update_interval)
+                       return 0644;
+               return 0;
+       }
+
+       switch (attr) {
+       case hwmon_temp_input:
+       case hwmon_temp_max_alarm:
+       case hwmon_temp_crit_alarm:
+       case hwmon_temp_crit_hyst:
+               return 0444;
+       case hwmon_temp_enable:
+       case hwmon_temp_max:
+       case hwmon_temp_crit:
+               return 0644;
+       case hwmon_temp_max_hyst:
+               if (!channel)
+                       return 0644;
+               return 0444;
+       case hwmon_temp_label:
+               if (data->channel[channel].label)
+                       return 0444;
+               return 0;
+       case hwmon_temp_fault:
+               if (channel)
+                       return 0444;
+               return 0;
+       case hwmon_temp_offset:
+               if (channel)
+                       return 0644;
+               return 0;
+       default:
+               return 0;
+       }
+}
+
+static void tmp464_restore_lock(void *regmap)
+{
+       regmap_write(regmap, TMP464_LOCK_REG, TMP464_LOCK_VAL);
+}
+
+static void tmp464_restore_config(void *_data)
+{
+       struct tmp464_data *data = _data;
+
+       regmap_write(data->regmap, TMP464_CONFIG_REG, data->config_orig);
+}
+
+static int tmp464_init_client(struct device *dev, struct tmp464_data *data)
+{
+       struct regmap *regmap = data->regmap;
+       unsigned int regval;
+       int err;
+
+       err = regmap_read(regmap, TMP464_LOCK_REG, &regval);
+       if (err)
+               return err;
+       if (regval == TMP464_LOCKED) {
+               /* Explicitly unlock chip if it is locked */
+               err = regmap_write(regmap, TMP464_LOCK_REG, TMP464_UNLOCK_VAL);
+               if (err)
+                       return err;
+               /* and lock it again when unloading the driver */
+               err = devm_add_action_or_reset(dev, tmp464_restore_lock, regmap);
+               if (err)
+                       return err;
+       }
+
+       err = regmap_read(regmap, TMP464_CONFIG_REG, &regval);
+       if (err)
+               return err;
+       data->config_orig = regval;
+       err = devm_add_action_or_reset(dev, tmp464_restore_config, data);
+       if (err)
+               return err;
+
+       /* Default to 500 ms update interval */
+       err = regmap_update_bits(regmap, TMP464_CONFIG_REG,
+                                TMP464_CONFIG_CONVERSION_RATE_MASK | TMP464_CONFIG_SHUTDOWN,
+                                BIT(TMP464_CONFIG_CONVERSION_RATE_B0) |
+                                BIT(TMP464_CONFIG_CONVERSION_RATE_B2));
+       if (err)
+               return err;
+
+       data->update_interval = 500;
+
+       return tmp464_enable_channels(data);
+}
+
+static int tmp464_detect(struct i2c_client *client,
+                        struct i2c_board_info *info)
+{
+       struct i2c_adapter *adapter = client->adapter;
+       char *name, *chip;
+       int reg;
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
+               return -ENODEV;
+
+       reg = i2c_smbus_read_word_swapped(client, TMP464_MANUFACTURER_ID_REG);
+       if (reg < 0)
+               return reg;
+       if (reg != TMP464_MANUFACTURER_ID)
+               return -ENODEV;
+
+       /* Check for "always return zero" bits */
+       reg = i2c_smbus_read_word_swapped(client, TMP464_THERM_STATUS_REG);
+       if (reg < 0)
+               return reg;
+       if (reg & 0x1f)
+               return -ENODEV;
+       reg = i2c_smbus_read_word_swapped(client, TMP464_THERM2_STATUS_REG);
+       if (reg < 0)
+               return reg;
+       if (reg & 0x1f)
+               return -ENODEV;
+
+       reg = i2c_smbus_read_word_swapped(client, TMP464_DEVICE_ID_REG);
+       if (reg < 0)
+               return reg;
+       switch (reg) {
+       case TMP464_DEVICE_ID:
+               name = "tmp464";
+               chip = "TMP464";
+               break;
+       case TMP468_DEVICE_ID:
+               name = "tmp468";
+               chip = "TMP468";
+               break;
+       default:
+               return -ENODEV;
+       }
+
+       strscpy(info->type, name, I2C_NAME_SIZE);
+       dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n", chip, client->addr);
+
+       return 0;
+}
+
+static int tmp464_probe_child_from_dt(struct device *dev,
+                                     struct device_node *child,
+                                     struct tmp464_data *data)
+
+{
+       struct regmap *regmap = data->regmap;
+       u32 channel;
+       s32 nfactor;
+       int err;
+
+       err = of_property_read_u32(child, "reg", &channel);
+       if (err) {
+               dev_err(dev, "missing reg property of %pOFn\n", child);
+               return err;
+       }
+
+       if (channel >= data->channels) {
+               dev_err(dev, "invalid reg %d of %pOFn\n", channel, child);
+               return -EINVAL;
+       }
+
+       of_property_read_string(child, "label", &data->channel[channel].label);
+
+       data->channel[channel].enabled = of_device_is_available(child);
+
+       err = of_property_read_s32(child, "ti,n-factor", &nfactor);
+       if (err && err != -EINVAL)
+               return err;
+       if (!err) {
+               if (channel == 0) {
+                       dev_err(dev, "n-factor can't be set for internal channel\n");
+                       return -EINVAL;
+               }
+               if (nfactor > 127 || nfactor < -128) {
+                       dev_err(dev, "n-factor for channel %d invalid (%d)\n",
+                               channel, nfactor);
+                       return -EINVAL;
+               }
+               err = regmap_write(regmap, TMP464_N_FACTOR_REG(channel),
+                                  (nfactor << 8) & 0xff00);
+               if (err)
+                       return err;
+       }
+
+       return 0;
+}
+
+static int tmp464_probe_from_dt(struct device *dev, struct tmp464_data *data)
+{
+       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 = tmp464_probe_child_from_dt(dev, child, data);
+               if (err) {
+                       of_node_put(child);
+                       return err;
+               }
+       }
+
+       return 0;
+}
+
+static const struct hwmon_ops tmp464_ops = {
+       .is_visible = tmp464_is_visible,
+       .read = tmp464_read,
+       .read_string = tmp464_read_string,
+       .write = tmp464_write,
+};
+
+static const struct hwmon_channel_info *tmp464_info[] = {
+       HWMON_CHANNEL_INFO(chip,
+                          HWMON_C_UPDATE_INTERVAL),
+       HWMON_CHANNEL_INFO(temp,
+                          HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_CRIT |
+                          HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
+                          HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
+                          HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
+                          HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE),
+       NULL
+};
+
+static const struct hwmon_chip_info tmp464_chip_info = {
+       .ops = &tmp464_ops,
+       .info = tmp464_info,
+};
+
+/* regmap */
+
+static bool tmp464_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+       return (reg < TMP464_TEMP_REG(TMP468_NUM_CHANNELS) ||
+               reg == TMP464_THERM_STATUS_REG ||
+               reg == TMP464_THERM2_STATUS_REG ||
+               reg == TMP464_REMOTE_OPEN_REG);
+}
+
+static const struct regmap_config tmp464_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 16,
+       .max_register = TMP464_DEVICE_ID_REG,
+       .volatile_reg = tmp464_is_volatile_reg,
+       .val_format_endian = REGMAP_ENDIAN_BIG,
+       .cache_type = REGCACHE_RBTREE,
+       .use_single_read = true,
+       .use_single_write = true,
+};
+
+static int tmp464_probe(struct i2c_client *client)
+{
+       struct device *dev = &client->dev;
+       struct device *hwmon_dev;
+       struct tmp464_data *data;
+       int i, err;
+
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
+               dev_err(&client->dev, "i2c functionality check failed\n");
+               return -ENODEV;
+       }
+       data = devm_kzalloc(dev, sizeof(struct tmp464_data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       mutex_init(&data->update_lock);
+
+       if (dev->of_node)
+               data->channels = (int)(unsigned long)of_device_get_match_data(&client->dev);
+       else
+               data->channels = i2c_match_id(tmp464_id, client)->driver_data;
+
+       data->regmap = devm_regmap_init_i2c(client, &tmp464_regmap_config);
+       if (IS_ERR(data->regmap))
+               return PTR_ERR(data->regmap);
+
+       for (i = 0; i < data->channels; i++)
+               data->channel[i].enabled = true;
+
+       err = tmp464_init_client(dev, data);
+       if (err)
+               return err;
+
+       if (dev->of_node) {
+               err = tmp464_probe_from_dt(dev, data);
+               if (err)
+                       return err;
+       }
+
+       hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+                                                        data, &tmp464_chip_info, NULL);
+       return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct i2c_driver tmp464_driver = {
+       .class = I2C_CLASS_HWMON,
+       .driver = {
+               .name   = "tmp464",
+               .of_match_table = of_match_ptr(tmp464_of_match),
+       },
+       .probe_new = tmp464_probe,
+       .id_table = tmp464_id,
+       .detect = tmp464_detect,
+       .address_list = normal_i2c,
+};
+
+module_i2c_driver(tmp464_driver);
+
+MODULE_AUTHOR("Agathe Porte <agathe.porte@nokia.com>");
+MODULE_DESCRIPTION("Texas Instruments TMP464 temperature sensor driver");
+MODULE_LICENSE("GPL");