hwmon: Driver for TI ADC128D818

ADC128D818 is a System Monitor with Temperature Sensor. It is similar to LM80
and LM96080, but has 16 bit wide sensor registers and no fan speed monitoring.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 491 insertions, 0 deletions

diff --git a/drivers/hwmon/adc128d818.c b/drivers/hwmon/adc128d818.c
new file mode 100644
index 000000000000..5ffd81f19d01
--- /dev/null
+++ b/drivers/hwmon/adc128d818.c
@@ -0,0 +1,491 @@
+/*
+ * Driver for TI ADC128D818 System Monitor with Temperature Sensor
+ *
+ * Copyright (c) 2014 Guenter Roeck
+ *
+ * Derived from lm80.c
+ * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
+ *                           and Philip Edelbrock <phil@netroedge.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.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/regulator/consumer.h>
+#include <linux/mutex.h>
+
+/* Addresses to scan
+ * The chip also supports addresses 0x35..0x37. Don't scan those addresses
+ * since they are also used by some EEPROMs, which may result in false
+ * positives.
+ */
+static const unsigned short normal_i2c[] = {
+        0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
+
+/* registers */
+#define ADC128_REG_IN_MAX(nr)           (0x2a + (nr) * 2)
+#define ADC128_REG_IN_MIN(nr)           (0x2b + (nr) * 2)
+#define ADC128_REG_IN(nr)               (0x20 + (nr))
+
+#define ADC128_REG_TEMP                 0x27
+#define ADC128_REG_TEMP_MAX             0x38
+#define ADC128_REG_TEMP_HYST            0x39
+
+#define ADC128_REG_CONFIG               0x00
+#define ADC128_REG_ALARM                0x01
+#define ADC128_REG_MASK                 0x03
+#define ADC128_REG_CONV_RATE            0x07
+#define ADC128_REG_ONESHOT              0x09
+#define ADC128_REG_SHUTDOWN             0x0a
+#define ADC128_REG_CONFIG_ADV           0x0b
+#define ADC128_REG_BUSY_STATUS          0x0c
+
+#define ADC128_REG_MAN_ID               0x3e
+#define ADC128_REG_DEV_ID               0x3f
+
+struct adc128_data {
+        struct i2c_client *client;
+        struct regulator *regulator;
+        int vref;               /* Reference voltage in mV */
+        struct mutex update_lock;
+        bool valid;             /* true if following fields are valid */
+        unsigned long last_updated;     /* In jiffies */
+
+        u16 in[3][7];           /* Register value, normalized to 12 bit
+                                 * 0: input voltage
+                                 * 1: min limit
+                                 * 2: max limit
+                                 */
+        s16 temp[3];            /* Register value, normalized to 9 bit
+                                 * 0: sensor 1: limit 2: hyst
+                                 */
+        u8 alarms;              /* alarm register value */
+};
+
+static struct adc128_data *adc128_update_device(struct device *dev)
+{
+        struct adc128_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = data->client;
+        struct adc128_data *ret = data;
+        int i, rv;
+
+        mutex_lock(&data->update_lock);
+
+        if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+                for (i = 0; i < 7; i++) {
+                        rv = i2c_smbus_read_word_swapped(client,
+                                                         ADC128_REG_IN(i));
+                        if (rv < 0)
+                                goto abort;
+                        data->in[0][i] = rv >> 4;
+
+                        rv = i2c_smbus_read_byte_data(client,
+                                                      ADC128_REG_IN_MIN(i));
+                        if (rv < 0)
+                                goto abort;
+                        data->in[1][i] = rv << 4;
+
+                        rv = i2c_smbus_read_byte_data(client,
+                                                      ADC128_REG_IN_MAX(i));
+                        if (rv < 0)
+                                goto abort;
+                        data->in[2][i] = rv << 4;
+                }
+
+                rv = i2c_smbus_read_word_swapped(client, ADC128_REG_TEMP);
+                if (rv < 0)
+                        goto abort;
+                data->temp[0] = rv >> 7;
+
+                rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_MAX);
+                if (rv < 0)
+                        goto abort;
+                data->temp[1] = rv << 1;
+
+                rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_HYST);
+                if (rv < 0)
+                        goto abort;
+                data->temp[2] = rv << 1;
+
+                rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
+                if (rv < 0)
+                        goto abort;
+                data->alarms |= rv;
+
+                data->last_updated = jiffies;
+                data->valid = true;
+        }
+        goto done;
+
+abort:
+        ret = ERR_PTR(rv);
+        data->valid = false;
+done:
+        mutex_unlock(&data->update_lock);
+        return ret;
+}
+
+static ssize_t adc128_show_in(struct device *dev, struct device_attribute *attr,
+                              char *buf)
+{
+        struct adc128_data *data = adc128_update_device(dev);
+        int index = to_sensor_dev_attr_2(attr)->index;
+        int nr = to_sensor_dev_attr_2(attr)->nr;
+        int val;
+
+        if (IS_ERR(data))
+                return PTR_ERR(data);
+
+        val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
+        return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t adc128_set_in(struct device *dev, struct device_attribute *attr,
+                             const char *buf, size_t count)
+{
+        struct adc128_data *data = dev_get_drvdata(dev);
+        int index = to_sensor_dev_attr_2(attr)->index;
+        int nr = to_sensor_dev_attr_2(attr)->nr;
+        u8 reg, regval;
+        long val;
+        int err;
+
+        err = kstrtol(buf, 10, &val);
+        if (err < 0)
+                return err;
+
+        mutex_lock(&data->update_lock);
+        /* 10 mV LSB on limit registers */
+        regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
+        data->in[index][nr] = regval << 4;
+        reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
+        i2c_smbus_write_byte_data(data->client, reg, regval);
+        mutex_unlock(&data->update_lock);
+
+        return count;
+}
+
+static ssize_t adc128_show_temp(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+        struct adc128_data *data = adc128_update_device(dev);
+        int index = to_sensor_dev_attr(attr)->index;
+        int temp;
+
+        if (IS_ERR(data))
+                return PTR_ERR(data);
+
+        temp = (data->temp[index] << 7) >> 7;   /* sign extend */
+        return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
+}
+
+static ssize_t adc128_set_temp(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+        struct adc128_data *data = dev_get_drvdata(dev);
+        int index = to_sensor_dev_attr(attr)->index;
+        long val;
+        int err;
+        s8 regval;
+
+        err = kstrtol(buf, 10, &val);
+        if (err < 0)
+                return err;
+
+        mutex_lock(&data->update_lock);
+        regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
+        data->temp[index] = regval << 1;
+        i2c_smbus_write_byte_data(data->client,
+                                  index == 1 ? ADC128_REG_TEMP_MAX
+                                             : ADC128_REG_TEMP_HYST,
+                                  regval);
+        mutex_unlock(&data->update_lock);
+
+        return count;
+}
+
+static ssize_t adc128_show_alarm(struct device *dev,
+                                 struct device_attribute *attr, char *buf)
+{
+        struct adc128_data *data = adc128_update_device(dev);
+        int mask = 1 << to_sensor_dev_attr(attr)->index;
+        u8 alarms;
+
+        if (IS_ERR(data))
+                return PTR_ERR(data);
+
+        /*
+         * Clear an alarm after reporting it to user space. If it is still
+         * active, the next update sequence will set the alarm bit again.
+         */
+        alarms = data->alarms;
+        data->alarms &= ~mask;
+
+        return sprintf(buf, "%u\n", !!(alarms & mask));
+}
+
+static SENSOR_DEVICE_ATTR_2(in0_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 0, 0);
+static SENSOR_DEVICE_ATTR_2(in0_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 0, 1);
+static SENSOR_DEVICE_ATTR_2(in0_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 0, 2);
+
+static SENSOR_DEVICE_ATTR_2(in1_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 1, 0);
+static SENSOR_DEVICE_ATTR_2(in1_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 1, 1);
+static SENSOR_DEVICE_ATTR_2(in1_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 1, 2);
+
+static SENSOR_DEVICE_ATTR_2(in2_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 2, 0);
+static SENSOR_DEVICE_ATTR_2(in2_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 2, 1);
+static SENSOR_DEVICE_ATTR_2(in2_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 2, 2);
+
+static SENSOR_DEVICE_ATTR_2(in3_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 3, 0);
+static SENSOR_DEVICE_ATTR_2(in3_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 3, 1);
+static SENSOR_DEVICE_ATTR_2(in3_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 3, 2);
+
+static SENSOR_DEVICE_ATTR_2(in4_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 4, 0);
+static SENSOR_DEVICE_ATTR_2(in4_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 4, 1);
+static SENSOR_DEVICE_ATTR_2(in4_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 4, 2);
+
+static SENSOR_DEVICE_ATTR_2(in5_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 5, 0);
+static SENSOR_DEVICE_ATTR_2(in5_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 5, 1);
+static SENSOR_DEVICE_ATTR_2(in5_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 5, 2);
+
+static SENSOR_DEVICE_ATTR_2(in6_input, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 6, 0);
+static SENSOR_DEVICE_ATTR_2(in6_min, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 6, 1);
+static SENSOR_DEVICE_ATTR_2(in6_max, S_IWUSR | S_IRUGO,
+                            adc128_show_in, adc128_set_in, 6, 2);
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adc128_show_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+                          adc128_show_temp, adc128_set_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
+                          adc128_show_temp, adc128_set_temp, 2);
+
+static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, adc128_show_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, adc128_show_alarm, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, adc128_show_alarm, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, adc128_show_alarm, NULL, 3);
+static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, adc128_show_alarm, NULL, 4);
+static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, adc128_show_alarm, NULL, 5);
+static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, adc128_show_alarm, NULL, 6);
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adc128_show_alarm, NULL, 7);
+
+static struct attribute *adc128_attrs[] = {
+        &sensor_dev_attr_in0_min.dev_attr.attr,
+        &sensor_dev_attr_in1_min.dev_attr.attr,
+        &sensor_dev_attr_in2_min.dev_attr.attr,
+        &sensor_dev_attr_in3_min.dev_attr.attr,
+        &sensor_dev_attr_in4_min.dev_attr.attr,
+        &sensor_dev_attr_in5_min.dev_attr.attr,
+        &sensor_dev_attr_in6_min.dev_attr.attr,
+        &sensor_dev_attr_in0_max.dev_attr.attr,
+        &sensor_dev_attr_in1_max.dev_attr.attr,
+        &sensor_dev_attr_in2_max.dev_attr.attr,
+        &sensor_dev_attr_in3_max.dev_attr.attr,
+        &sensor_dev_attr_in4_max.dev_attr.attr,
+        &sensor_dev_attr_in5_max.dev_attr.attr,
+        &sensor_dev_attr_in6_max.dev_attr.attr,
+        &sensor_dev_attr_in0_input.dev_attr.attr,
+        &sensor_dev_attr_in1_input.dev_attr.attr,
+        &sensor_dev_attr_in2_input.dev_attr.attr,
+        &sensor_dev_attr_in3_input.dev_attr.attr,
+        &sensor_dev_attr_in4_input.dev_attr.attr,
+        &sensor_dev_attr_in5_input.dev_attr.attr,
+        &sensor_dev_attr_in6_input.dev_attr.attr,
+        &sensor_dev_attr_temp1_input.dev_attr.attr,
+        &sensor_dev_attr_temp1_max.dev_attr.attr,
+        &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+        &sensor_dev_attr_in0_alarm.dev_attr.attr,
+        &sensor_dev_attr_in1_alarm.dev_attr.attr,
+        &sensor_dev_attr_in2_alarm.dev_attr.attr,
+        &sensor_dev_attr_in3_alarm.dev_attr.attr,
+        &sensor_dev_attr_in4_alarm.dev_attr.attr,
+        &sensor_dev_attr_in5_alarm.dev_attr.attr,
+        &sensor_dev_attr_in6_alarm.dev_attr.attr,
+        &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+        NULL
+};
+ATTRIBUTE_GROUPS(adc128);
+
+static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
+{
+        int man_id, dev_id;
+
+        if (!i2c_check_functionality(client->adapter,
+                                     I2C_FUNC_SMBUS_BYTE_DATA |
+                                     I2C_FUNC_SMBUS_WORD_DATA))
+                return -ENODEV;
+
+        man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
+        dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
+        if (man_id != 0x01 || dev_id != 0x09)
+                return -ENODEV;
+
+        /* Check unused bits for confirmation */
+        if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
+                return -ENODEV;
+        if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
+                return -ENODEV;
+        if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
+                return -ENODEV;
+        if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
+                return -ENODEV;
+        if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
+                return -ENODEV;
+        if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
+                return -ENODEV;
+
+        strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
+
+        return 0;
+}
+
+static int adc128_init_client(struct adc128_data *data)
+{
+        struct i2c_client *client = data->client;
+        int err;
+
+        /*
+         * Reset chip to defaults.
+         * This makes most other initializations unnecessary.
+         */
+        err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
+        if (err)
+                return err;
+
+        /* Start monitoring */
+        err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
+        if (err)
+                return err;
+
+        /* If external vref is selected, configure the chip to use it */
+        if (data->regulator) {
+                err = i2c_smbus_write_byte_data(client,
+                                                ADC128_REG_CONFIG_ADV, 0x01);
+                if (err)
+                        return err;
+        }
+
+        return 0;
+}
+
+static int adc128_probe(struct i2c_client *client,
+                        const struct i2c_device_id *id)
+{
+        struct device *dev = &client->dev;
+        struct regulator *regulator;
+        struct device *hwmon_dev;
+        struct adc128_data *data;
+        int err, vref;
+
+        data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        /* vref is optional. If specified, is used as chip reference voltage */
+        regulator = devm_regulator_get_optional(dev, "vref");
+        if (!IS_ERR(regulator)) {
+                data->regulator = regulator;
+                err = regulator_enable(regulator);
+                if (err < 0)
+                        return err;
+                vref = regulator_get_voltage(regulator);
+                if (vref < 0) {
+                        err = vref;
+                        goto error;
+                }
+                data->vref = DIV_ROUND_CLOSEST(vref, 1000);
+        } else {
+                data->vref = 2560;      /* 2.56V, in mV */
+        }
+
+        data->client = client;
+        i2c_set_clientdata(client, data);
+        mutex_init(&data->update_lock);
+
+        /* Initialize the chip */
+        err = adc128_init_client(data);
+        if (err < 0)
+                goto error;
+
+        hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+                                                           data, adc128_groups);
+        if (IS_ERR(hwmon_dev)) {
+                err = PTR_ERR(hwmon_dev);
+                goto error;
+        }
+
+        return 0;
+
+error:
+        if (data->regulator)
+                regulator_disable(data->regulator);
+        return err;
+}
+
+static int adc128_remove(struct i2c_client *client)
+{
+        struct adc128_data *data = i2c_get_clientdata(client);
+
+        if (data->regulator)
+                regulator_disable(data->regulator);
+
+        return 0;
+}
+
+static const struct i2c_device_id adc128_id[] = {
+        { "adc128d818", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, adc128_id);
+
+static struct i2c_driver adc128_driver = {
+        .class          = I2C_CLASS_HWMON,
+        .driver = {
+                .name   = "adc128d818",
+        },
+        .probe          = adc128_probe,
+        .remove         = adc128_remove,
+        .id_table       = adc128_id,
+        .detect         = adc128_detect,
+        .address_list   = normal_i2c,
+};
+
+module_i2c_driver(adc128_driver);
+
+MODULE_AUTHOR("Guenter Roeck");
+MODULE_DESCRIPTION("Driver for ADC128D818");
+MODULE_LICENSE("GPL");