hwmon: (lm90) Support ADT7461 in extended mode
Support ADT7461 in extended temperature range mode, which will change
the range of readings from 0..127 to -64..191 degC. Adjust the
register conversion functions accordingly.
Signed-off-by: Nate Case <ncase@xes-inc.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Martyn Welch <martyn.welch@gefanuc.com>
diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index b2d9b3f..fe5d860 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -37,11 +37,10 @@
* chips. The MAX6680 and MAX6681 only differ in the pinout so they can
* be treated identically.
*
- * This driver also supports the ADT7461 chip from Analog Devices but
- * only in its "compatability mode". If an ADT7461 chip is found but
- * is configured in non-compatible mode (where its temperature
- * register values are decoded differently) it is ignored by this
- * driver.
+ * This driver also supports the ADT7461 chip from Analog Devices.
+ * It's supported in both compatibility and extended mode. It is mostly
+ * compatible with LM90 except for a data format difference for the
+ * temperature value registers.
*
* Since the LM90 was the first chipset supported by this driver, most
* comments will refer to this chipset, but are actually general and
@@ -138,6 +137,11 @@
#define MAX6657_REG_R_LOCAL_TEMPL 0x11
/*
+ * Device flags
+ */
+#define LM90_FLAG_ADT7461_EXT 0x01 /* ADT7461 extended mode */
+
+/*
* Functions declaration
*/
@@ -191,6 +195,7 @@
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
int kind;
+ int flags;
/* registers values */
s8 temp8[4]; /* 0: local low limit
@@ -256,26 +261,61 @@
}
/*
- * ADT7461 is almost identical to LM90 except that attempts to write
- * values that are outside the range 0 < temp < 127 are treated as
- * the boundary value.
+ * ADT7461 in compatibility mode is almost identical to LM90 except that
+ * attempts to write values that are outside the range 0 < temp < 127 are
+ * treated as the boundary value.
+ *
+ * ADT7461 in "extended mode" operation uses unsigned integers offset by
+ * 64 (e.g., 0 -> -64 degC). The range is restricted to -64..191 degC.
*/
-static u8 temp1_to_reg_adt7461(long val)
+static inline int temp1_from_reg_adt7461(struct lm90_data *data, u8 val)
{
- if (val <= 0)
- return 0;
- if (val >= 127000)
- return 127;
- return (val + 500) / 1000;
+ if (data->flags & LM90_FLAG_ADT7461_EXT)
+ return (val - 64) * 1000;
+ else
+ return temp1_from_reg(val);
}
-static u16 temp2_to_reg_adt7461(long val)
+static inline int temp2_from_reg_adt7461(struct lm90_data *data, u16 val)
{
- if (val <= 0)
- return 0;
- if (val >= 127750)
- return 0x7FC0;
- return (val + 125) / 250 * 64;
+ if (data->flags & LM90_FLAG_ADT7461_EXT)
+ return (val - 0x4000) / 64 * 250;
+ else
+ return temp2_from_reg(val);
+}
+
+static u8 temp1_to_reg_adt7461(struct lm90_data *data, long val)
+{
+ if (data->flags & LM90_FLAG_ADT7461_EXT) {
+ if (val <= -64000)
+ return 0;
+ if (val >= 191000)
+ return 0xFF;
+ return (val + 500 + 64000) / 1000;
+ } else {
+ if (val <= 0)
+ return 0;
+ if (val >= 127000)
+ return 127;
+ return (val + 500) / 1000;
+ }
+}
+
+static u16 temp2_to_reg_adt7461(struct lm90_data *data, long val)
+{
+ if (data->flags & LM90_FLAG_ADT7461_EXT) {
+ if (val <= -64000)
+ return 0;
+ if (val >= 191750)
+ return 0xFFC0;
+ return (val + 64000 + 125) / 250 * 64;
+ } else {
+ if (val <= 0)
+ return 0;
+ if (val >= 127750)
+ return 0x7FC0;
+ return (val + 125) / 250 * 64;
+ }
}
/*
@@ -287,7 +327,14 @@
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct lm90_data *data = lm90_update_device(dev);
- return sprintf(buf, "%d\n", temp1_from_reg(data->temp8[attr->index]));
+ int temp;
+
+ if (data->kind == adt7461)
+ temp = temp1_from_reg_adt7461(data, data->temp8[attr->index]);
+ else
+ temp = temp1_from_reg(data->temp8[attr->index]);
+
+ return sprintf(buf, "%d\n", temp);
}
static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
@@ -308,7 +355,7 @@
mutex_lock(&data->update_lock);
if (data->kind == adt7461)
- data->temp8[nr] = temp1_to_reg_adt7461(val);
+ data->temp8[nr] = temp1_to_reg_adt7461(data, val);
else
data->temp8[nr] = temp1_to_reg(val);
i2c_smbus_write_byte_data(client, reg[nr], data->temp8[nr]);
@@ -321,7 +368,14 @@
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct lm90_data *data = lm90_update_device(dev);
- return sprintf(buf, "%d\n", temp2_from_reg(data->temp11[attr->index]));
+ int temp;
+
+ if (data->kind == adt7461)
+ temp = temp2_from_reg_adt7461(data, data->temp11[attr->index]);
+ else
+ temp = temp2_from_reg(data->temp11[attr->index]);
+
+ return sprintf(buf, "%d\n", temp);
}
static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
@@ -344,7 +398,7 @@
mutex_lock(&data->update_lock);
if (data->kind == adt7461)
- data->temp11[nr] = temp2_to_reg_adt7461(val);
+ data->temp11[nr] = temp2_to_reg_adt7461(data, val);
else if (data->kind == max6657 || data->kind == max6680)
data->temp11[nr] = temp1_to_reg(val) << 8;
else
@@ -364,8 +418,14 @@
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct lm90_data *data = lm90_update_device(dev);
- return sprintf(buf, "%d\n", temp1_from_reg(data->temp8[attr->index])
- - temp1_from_reg(data->temp_hyst));
+ int temp;
+
+ if (data->kind == adt7461)
+ temp = temp1_from_reg_adt7461(data, data->temp8[attr->index]);
+ else
+ temp = temp1_from_reg(data->temp8[attr->index]);
+
+ return sprintf(buf, "%d\n", temp - temp1_from_reg(data->temp_hyst));
}
static ssize_t set_temphyst(struct device *dev, struct device_attribute *dummy,
@@ -598,7 +658,7 @@
kind = adm1032;
} else
if (chip_id == 0x51 /* ADT7461 */
- && (reg_config1 & 0x1F) == 0x00 /* check compat mode */
+ && (reg_config1 & 0x1B) == 0x00
&& reg_convrate <= 0x0A) {
kind = adt7461;
}
@@ -737,6 +797,12 @@
}
config_orig = config;
+ /* Check Temperature Range Select */
+ if (data->kind == adt7461) {
+ if (config & 0x04)
+ data->flags |= LM90_FLAG_ADT7461_EXT;
+ }
+
/*
* Put MAX6680/MAX8881 into extended resolution (bit 0x10,
* 0.125 degree resolution) and range (0x08, extend range
