[3.13.y.z extended stable] Patch "hwmon: (adm1031) Fix writes to limit registers" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    hwmon: (adm1031) Fix writes to limit registers

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.6.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From a4f04fa89b97798216200daa59e712ad0ed274a7 Mon Sep 17 00:00:00 2001
From: Guenter Roeck <linux at roeck-us.net>
Date: Thu, 3 Jul 2014 13:44:23 -0700
Subject: hwmon: (adm1031) Fix writes to limit registers

commit 145e74a4e5022225adb84f4e5d4fff7938475c35 upstream.

Upper limit for write operations to temperature limit registers
was clamped to a fractional value. However, limit registers do
not support fractional values. As a result, upper limits of 127.5
degrees C or higher resulted in a rounded limit of 128 degrees C.
Since limit registers are signed, this was stored as -128 degrees C.
Clamp limits to (-55, +127) degrees C to solve the problem.

Value on writes to auto_temp[12]_min and auto_temp[12]_max were not
clamped at all, but masked. As a result, out-of-range writes resulted
in a more or less arbitrary limit. Clamp those attributes to (0, 127)
degrees C for more predictable results.

Cc: Axel Lin <axel.lin at ingics.com>
Reviewed-by: Jean Delvare <jdelvare at suse.de>
Signed-off-by: Guenter Roeck <linux at roeck-us.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/hwmon/adm1031.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/hwmon/adm1031.c b/drivers/hwmon/adm1031.c
index 253ea39..bdceca0 100644
--- a/drivers/hwmon/adm1031.c
+++ b/drivers/hwmon/adm1031.c
@@ -365,6 +365,7 @@ set_auto_temp_min(struct device *dev, struct device_attribute *attr,
 	if (ret)
 		return ret;

+	val = clamp_val(val, 0, 127000);
 	mutex_lock(&data->update_lock);
 	data->auto_temp[nr] = AUTO_TEMP_MIN_TO_REG(val, data->auto_temp[nr]);
 	adm1031_write_value(client, ADM1031_REG_AUTO_TEMP(nr),
@@ -394,6 +395,7 @@ set_auto_temp_max(struct device *dev, struct device_attribute *attr,
 	if (ret)
 		return ret;

+	val = clamp_val(val, 0, 127000);
 	mutex_lock(&data->update_lock);
 	data->temp_max[nr] = AUTO_TEMP_MAX_TO_REG(val, data->auto_temp[nr],
 						  data->pwm[nr]);
@@ -696,7 +698,7 @@ static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
 	if (ret)
 		return ret;

-	val = clamp_val(val, -55000, nr == 0 ? 127750 : 127875);
+	val = clamp_val(val, -55000, 127000);
 	mutex_lock(&data->update_lock);
 	data->temp_min[nr] = TEMP_TO_REG(val);
 	adm1031_write_value(client, ADM1031_REG_TEMP_MIN(nr),
@@ -717,7 +719,7 @@ static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
 	if (ret)
 		return ret;

-	val = clamp_val(val, -55000, nr == 0 ? 127750 : 127875);
+	val = clamp_val(val, -55000, 127000);
 	mutex_lock(&data->update_lock);
 	data->temp_max[nr] = TEMP_TO_REG(val);
 	adm1031_write_value(client, ADM1031_REG_TEMP_MAX(nr),
@@ -738,7 +740,7 @@ static ssize_t set_temp_crit(struct device *dev, struct device_attribute *attr,
 	if (ret)
 		return ret;

-	val = clamp_val(val, -55000, nr == 0 ? 127750 : 127875);
+	val = clamp_val(val, -55000, 127000);
 	mutex_lock(&data->update_lock);
 	data->temp_crit[nr] = TEMP_TO_REG(val);
 	adm1031_write_value(client, ADM1031_REG_TEMP_CRIT(nr),
--
1.9.1