summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorGuenter Roeck <linux@roeck-us.net>2013-11-20 19:25:17 +0100
committerGuenter Roeck <linux@roeck-us.net>2014-01-15 06:36:52 +0100
commitbf6ea084ebb54cf8e1d6e60aac3c727cf45bf6c7 (patch)
tree2a2feafbbaae6a0c5000bd217eb6e9327753af70 /drivers
parenthwmon: (da9052) Fix adc to voltage calculation (diff)
downloadlinux-bf6ea084ebb54cf8e1d6e60aac3c727cf45bf6c7.tar.xz
linux-bf6ea084ebb54cf8e1d6e60aac3c727cf45bf6c7.zip
hwmon: (coretemp) Do not return -EAGAIN for low temperatures
Some Intel CPUs do not set the 'valid' bit in IA32_THERM_STATUS if the temperature is too low to be measured. This condition will not change until the CPU is hot enough for its temperature to be measured. Returning an error in such conditions is not very useful. Drop checking the valid bit and just return the reported temperature instead. Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/hwmon/coretemp.c17
1 files changed, 9 insertions, 8 deletions
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index b2e59b395ce4..bbb0b0d463f7 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -177,18 +177,19 @@ static ssize_t show_temp(struct device *dev,
/* Check whether the time interval has elapsed */
if (!tdata->valid || time_after(jiffies, tdata->last_updated + HZ)) {
rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
- tdata->valid = 0;
- /* Check whether the data is valid */
- if (eax & 0x80000000) {
- tdata->temp = tdata->tjmax -
- ((eax >> 16) & 0x7f) * 1000;
- tdata->valid = 1;
- }
+ /*
+ * Ignore the valid bit. In all observed cases the register
+ * value is either low or zero if the valid bit is 0.
+ * Return it instead of reporting an error which doesn't
+ * really help at all.
+ */
+ tdata->temp = tdata->tjmax - ((eax >> 16) & 0x7f) * 1000;
+ tdata->valid = 1;
tdata->last_updated = jiffies;
}
mutex_unlock(&tdata->update_lock);
- return tdata->valid ? sprintf(buf, "%d\n", tdata->temp) : -EAGAIN;
+ return sprintf(buf, "%d\n", tdata->temp);
}
struct tjmax_pci {