hwmon: (lm75) Add support for the Dallas/Maxim DS7505

[karo-tx-linux.git] / drivers / hwmon / lm75.c

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index 291edfff55bfa033191448f69846603e5336eca6..c03b490bba813287d1d6368338743b450f34e687 100644 (file)
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -38,6 +38,7 @@ enum lm75_type {              /* keep sorted in alphabetical order */
        adt75,
        ds1775,
        ds75,
+       ds7505,
        lm75,
        lm75a,
        max6625,
@@ -71,9 +72,12 @@ struct lm75_data {
        struct device           *hwmon_dev;
        struct mutex            update_lock;
        u8                      orig_conf;
+       u8                      resolution;     /* In bits, between 9 and 12 */
+       u8                      resolution_limits;
        char                    valid;          /* !=0 if registers are valid */
        unsigned long           last_updated;   /* In jiffies */
-       u16                     temp[3];        /* Register values,
+       unsigned long           sample_time;    /* In jiffies */
+       s16                     temp[3];        /* Register values,
                                                   0 = input
                                                   1 = max
                                                   2 = hyst */
@@ -93,12 +97,15 @@ static ssize_t show_temp(struct device *dev, struct device_attribute *da,
 {
        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
        struct lm75_data *data = lm75_update_device(dev);
+       long temp;
 
        if (IS_ERR(data))
                return PTR_ERR(data);
 
-       return sprintf(buf, "%d\n",
-                      LM75_TEMP_FROM_REG(data->temp[attr->index]));
+       temp = ((data->temp[attr->index] >> (16 - data->resolution)) * 1000)
+              >> (data->resolution - 8);
+
+       return sprintf(buf, "%ld\n", temp);
 }
 
 static ssize_t set_temp(struct device *dev, struct device_attribute *da,
@@ -110,13 +117,25 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *da,
        int nr = attr->index;
        long temp;
        int error;
+       u8 resolution;
 
        error = kstrtol(buf, 10, &temp);
        if (error)
                return error;
 
+       /*
+        * Resolution of limit registers is assumed to be the same as the
+        * temperature input register resolution unless given explicitly.
+        */
+       if (attr->index && data->resolution_limits)
+               resolution = data->resolution_limits;
+       else
+               resolution = data->resolution;
+
        mutex_lock(&data->update_lock);
-       data->temp[nr] = LM75_TEMP_TO_REG(temp);
+       temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
+       data->temp[nr] = DIV_ROUND_CLOSEST(temp  << (resolution - 8),
+                                          1000) << (16 - resolution);
        lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]);
        mutex_unlock(&data->update_lock);
        return count;
@@ -151,6 +170,7 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
        int status;
        u8 set_mask, clr_mask;
        int new;
+       enum lm75_type kind = id->driver_data;
 
        if (!i2c_check_functionality(client->adapter,
                        I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
@@ -167,8 +187,65 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
         * Then tweak to be more precise when appropriate.
         */
        set_mask = 0;
-       clr_mask = (1 << 0)                     /* continuous conversions */
-               | (1 << 6) | (1 << 5);          /* 9-bit mode */
+       clr_mask = LM75_SHUTDOWN;               /* continuous conversions */
+
+       switch (kind) {
+       case adt75:
+               clr_mask |= 1 << 5;             /* not one-shot mode */
+               data->resolution = 12;
+               data->sample_time = HZ / 8;
+               break;
+       case ds1775:
+       case ds75:
+       case stds75:
+               clr_mask |= 3 << 5;
+               set_mask |= 2 << 5;             /* 11-bit mode */
+               data->resolution = 11;
+               data->sample_time = HZ;
+               break;
+       case ds7505:
+               set_mask |= 3 << 5;             /* 12-bit mode */
+               data->resolution = 12;
+               data->sample_time = HZ / 4;
+               break;
+       case lm75:
+       case lm75a:
+               data->resolution = 9;
+               data->sample_time = HZ / 2;
+               break;
+       case max6625:
+               data->resolution = 9;
+               data->sample_time = HZ / 4;
+               break;
+       case max6626:
+               data->resolution = 12;
+               data->resolution_limits = 9;
+               data->sample_time = HZ / 4;
+               break;
+       case tcn75:
+               data->resolution = 9;
+               data->sample_time = HZ / 8;
+               break;
+       case mcp980x:
+               data->resolution_limits = 9;
+               /* fall through */
+       case tmp100:
+       case tmp101:
+               set_mask |= 3 << 5;             /* 12-bit mode */
+               data->resolution = 12;
+               data->sample_time = HZ;
+               clr_mask |= 1 << 7;             /* not one-shot mode */
+               break;
+       case tmp105:
+       case tmp175:
+       case tmp275:
+       case tmp75:
+               set_mask |= 3 << 5;             /* 12-bit mode */
+               clr_mask |= 1 << 7;             /* not one-shot mode */
+               data->resolution = 12;
+               data->sample_time = HZ / 2;
+               break;
+       }
 
        /* configure as specified */
        status = lm75_read_value(client, LM75_REG_CONF);
@@ -218,6 +295,7 @@ static const struct i2c_device_id lm75_ids[] = {
        { "adt75", adt75, },
        { "ds1775", ds1775, },
        { "ds75", ds75, },
+       { "ds7505", ds7505, },
        { "lm75", lm75, },
        { "lm75a", lm75a, },
        { "max6625", max6625, },
@@ -407,7 +485,7 @@ static struct lm75_data *lm75_update_device(struct device *dev)
 
        mutex_lock(&data->update_lock);
 
-       if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+       if (time_after(jiffies, data->last_updated + data->sample_time)
            || !data->valid) {
                int i;
                dev_dbg(&client->dev, "Starting lm75 update\n");