[3.8.y.z extended stable] Patch "hwmon: (w83l768ng) Fix fan speed control range" 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: (w83l768ng) Fix fan speed control range

to the linux-3.8.y-queue branch of the 3.8.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-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.16.

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

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 581f078f707b147575e60b70b7e06aec2ddda791 Mon Sep 17 00:00:00 2001
From: Jean Delvare <khali at linux-fr.org>
Date: Thu, 12 Dec 2013 08:05:32 +0100
Subject: hwmon: (w83l768ng) Fix fan speed control range

commit 33a7ab91d509fa33b4bcd3ce0038cc80298050da upstream.

The W83L786NG stores the fan speed on 4 bits while the sysfs interface
uses a 0-255 range. Thus the driver should scale the user input down
to map it to the device range, and scale up the value read from the
device before presenting it to the user. The reserved register nibble
should be left unchanged.

Signed-off-by: Jean Delvare <khali at linux-fr.org>
Reviewed-by: Guenter Roeck <linux at roeck-us.net>
[ kamal: backport to 3.8 (context) ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/hwmon/w83l786ng.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/hwmon/w83l786ng.c b/drivers/hwmon/w83l786ng.c
index c7514e0..0cce70c 100644
--- a/drivers/hwmon/w83l786ng.c
+++ b/drivers/hwmon/w83l786ng.c
@@ -482,9 +482,11 @@ store_pwm(struct device *dev, struct device_attribute *attr,
 	if (err)
 		return err;
 	val = SENSORS_LIMIT(val, 0, 255);
+	val = DIV_ROUND_CLOSEST(val, 0x11);

 	mutex_lock(&data->update_lock);
-	data->pwm[nr] = val;
+	data->pwm[nr] = val * 0x11;
+	val |= w83l786ng_read_value(client, W83L786NG_REG_PWM[nr]) & 0xf0;
 	w83l786ng_write_value(client, W83L786NG_REG_PWM[nr], val);
 	mutex_unlock(&data->update_lock);
 	return count;
@@ -778,8 +780,9 @@ static struct w83l786ng_data *w83l786ng_update_device(struct device *dev)
 			    ? 0 : 1;
 			data->pwm_enable[i] =
 			    ((pwmcfg >> W83L786NG_PWM_ENABLE_SHIFT[i]) & 3) + 1;
-			data->pwm[i] = w83l786ng_read_value(client,
-			    W83L786NG_REG_PWM[i]);
+			data->pwm[i] =
+			    (w83l786ng_read_value(client, W83L786NG_REG_PWM[i])
+			     & 0x0f) * 0x11;
 		}


--
1.8.3.2