[PATCH] drm/radeon: use 0-255 rather than 0-100 for pwm fan range

Alex Deucher alexdeucher at gmail.com
Wed Feb 4 14:27:10 PST 2015


0-255 seems to be the preferred range for the pwm interface.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/radeon/radeon_pm.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
index 91e1bd2..9f758d3 100644
--- a/drivers/gpu/drm/radeon/radeon_pm.c
+++ b/drivers/gpu/drm/radeon/radeon_pm.c
@@ -585,7 +585,7 @@ static ssize_t radeon_hwmon_set_pwm1_enable(struct device *dev,
 	if (err)
 		return err;
 
-	switch(value) {
+	switch (value) {
 	case 1: /* manual, percent-based */
 		rdev->asic->dpm.fan_ctrl_set_mode(rdev, FDO_PWM_MODE_STATIC);
 		break;
@@ -608,7 +608,7 @@ static ssize_t radeon_hwmon_get_pwm1_max(struct device *dev,
 					 struct device_attribute *attr,
 					 char *buf)
 {
-	return sprintf(buf, "%i\n", 100); /* pwm uses percent-based fan-control */
+	return sprintf(buf, "%i\n", 255);
 }
 
 static ssize_t radeon_hwmon_set_pwm1(struct device *dev,
@@ -623,6 +623,8 @@ static ssize_t radeon_hwmon_set_pwm1(struct device *dev,
 	if (err)
 		return err;
 
+	value = (value * 100) / 255;
+
 	err = rdev->asic->dpm.set_fan_speed_percent(rdev, value);
 	if (err)
 		return err;
@@ -642,6 +644,8 @@ static ssize_t radeon_hwmon_get_pwm1(struct device *dev,
 	if (err)
 		return err;
 
+	speed = (speed * 255) / 100;
+
 	return sprintf(buf, "%i\n", speed);
 }
 
-- 
1.8.3.1



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