thermal: Add a function to get the minimum power

The thermal core already has a function to get the maximum power of a
cooling device: power_actor_get_max_power().  Add a function to get the
minimum power of a cooling device.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 5e5fc7015c7f..d9e525cc9c1c 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1013,6 +1013,34 @@ int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 }
 
 /**
+ * power_actor_get_min_power() - get the mainimum power that a cdev can consume
+ * @cdev:	pointer to &thermal_cooling_device
+ * @tz:		a valid thermal zone device pointer
+ * @min_power:	pointer in which to store the minimum power
+ *
+ * Calculate the minimum power consumption in milliwatts that the
+ * cooling device can currently consume and store it in @min_power.
+ *
+ * Return: 0 on success, -EINVAL if @cdev doesn't support the
+ * power_actor API or -E* on other error.
+ */
+int power_actor_get_min_power(struct thermal_cooling_device *cdev,
+			      struct thermal_zone_device *tz, u32 *min_power)
+{
+	unsigned long max_state;
+	int ret;
+
+	if (!cdev_is_power_actor(cdev))
+		return -EINVAL;
+
+	ret = cdev->ops->get_max_state(cdev, &max_state);
+	if (ret)
+		return ret;
+
+	return cdev->ops->state2power(cdev, tz, max_state, min_power);
+}
+
+/**
  * power_actor_set_power() - limit the maximum power that a cooling device can consume
  * @cdev:	pointer to &thermal_cooling_device
  * @instance:	thermal instance to update