drm/nouveau/therm: add support for fan-control modes

For now, only 2 control modes are available:
- NONE: The fan is never touched (default)
- MANUAL: The fan is set to the user-defined fan speed (pwm1)

This patch introduces a distinction between ptherm internal fan management
and external fan management. The latter is bound to respect the fan mode
while the first can still select the speed it wants unless the NONE mode
is selected. This is important for automatic fan management.

Signed-off-by: Martin Peres <martin.peres@labri.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_pm.c b/drivers/gpu/drm/nouveau/nouveau_pm.c
index 0dca191ee173..b9d5335df742 100644
--- a/drivers/gpu/drm/nouveau/nouveau_pm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_pm.c
@@ -503,6 +503,45 @@ nouveau_hwmon_show_fan0_input(struct device *d, struct device_attribute *attr,
 static SENSOR_DEVICE_ATTR(fan0_input, S_IRUGO, nouveau_hwmon_show_fan0_input,
 			  NULL, 0);
 
+ static ssize_t
+nouveau_hwmon_get_pwm1_enable(struct device *d,
+			   struct device_attribute *a, char *buf)
+{
+	struct drm_device *dev = dev_get_drvdata(d);
+	struct nouveau_drm *drm = nouveau_drm(dev);
+	struct nouveau_therm *therm = nouveau_therm(drm->device);
+	int ret;
+
+	ret = therm->attr_get(therm, NOUVEAU_THERM_ATTR_FAN_MODE);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%i\n", ret);
+}
+
+static ssize_t
+nouveau_hwmon_set_pwm1_enable(struct device *d, struct device_attribute *a,
+			   const char *buf, size_t count)
+{
+	struct drm_device *dev = dev_get_drvdata(d);
+	struct nouveau_drm *drm = nouveau_drm(dev);
+	struct nouveau_therm *therm = nouveau_therm(drm->device);
+	long value;
+	int ret;
+
+	if (strict_strtol(buf, 10, &value) == -EINVAL)
+		return -EINVAL;
+
+	ret = therm->attr_set(therm, NOUVEAU_THERM_ATTR_FAN_MODE, value);
+	if (ret)
+		return ret;
+	else
+		return count;
+}
+static SENSOR_DEVICE_ATTR(pwm1_enable, S_IRUGO | S_IWUSR,
+			  nouveau_hwmon_get_pwm1_enable,
+			  nouveau_hwmon_set_pwm1_enable, 0);
+
 static ssize_t
 nouveau_hwmon_get_pwm1(struct device *d, struct device_attribute *a, char *buf)
 {
@@ -638,6 +677,7 @@ static struct attribute *hwmon_fan_rpm_attributes[] = {
 	NULL
 };
 static struct attribute *hwmon_pwm_fan_attributes[] = {
+	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
 	&sensor_dev_attr_pwm1.dev_attr.attr,
 	&sensor_dev_attr_pwm1_min.dev_attr.attr,
 	&sensor_dev_attr_pwm1_max.dev_attr.attr,