Re: [PATCH] hwmon: (coretemp) Do not return -EAGAIN for low temperatures

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 12/07/2013 10:05 AM, Guenter Roeck wrote:
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.

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
I don't think we ever closed on this. Giving it a shot.


Comments, anyone ?

Guenter

  drivers/hwmon/coretemp.c |   17 +++++++++--------
  1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index 310ce19..6e0579e 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 {



_______________________________________________
lm-sensors mailing list
lm-sensors@xxxxxxxxxxxxxx
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors




[Index of Archives]     [Linux Kernel]     [Linux Hardware Monitoring]     [Linux USB Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]

  Powered by Linux