1 files changed, 20 insertions, 10 deletions

diff --git a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
index e3c5e677eaa..8e67ebf9840 100644
--- a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
+++ b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
@@ -38,6 +38,7 @@
 /* common data structures */
 struct ti_thermal_data {
 	struct thermal_zone_device *ti_thermal;
+	struct thermal_zone_device *pcb_tz;
 	struct thermal_cooling_device *cool_dev;
 	struct ti_bandgap *bgp;
 	enum thermal_device_mode mode;
@@ -77,10 +78,12 @@ static inline int ti_thermal_hotspot_temperature(int t, int s, int c)
 static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
 				      unsigned long *temp)
 {
+	struct thermal_zone_device *pcb_tz = NULL;
 	struct ti_thermal_data *data = thermal->devdata;
 	struct ti_bandgap *bgp;
 	const struct ti_temp_sensor *s;
-	int ret, tmp, pcb_temp, slope, constant;
+	int ret, tmp, slope, constant;
+	unsigned long pcb_temp;
 
 	if (!data)
 		return 0;
@@ -92,16 +95,22 @@ static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
 	if (ret)
 		return ret;
 
-	pcb_temp = 0;
-	/* TODO: Introduce pcb temperature lookup */
+	/* Default constants */
+	slope = s->slope;
+	constant = s->constant;
+
+	pcb_tz = data->pcb_tz;
 	/* In case pcb zone is available, use the extrapolation rule with it */
-	if (pcb_temp) {
-		tmp -= pcb_temp;
-		slope = s->slope_pcb;
-		constant = s->constant_pcb;
-	} else {
-		slope = s->slope;
-		constant = s->constant;
+	if (!IS_ERR_OR_NULL(pcb_tz)) {
+		ret = thermal_zone_get_temp(pcb_tz, &pcb_temp);
+		if (!ret) {
+			tmp -= pcb_temp; /* got a valid PCB temp */
+			slope = s->slope_pcb;
+			constant = s->constant_pcb;
+		} else {
+			dev_err(bgp->dev,
+				"Failed to read PCB state. Using defaults\n");
+		}
 	}
 	*temp = ti_thermal_hotspot_temperature(tmp, slope, constant);
 
@@ -273,6 +282,7 @@ static struct ti_thermal_data
 	data->sensor_id = id;
 	data->bgp = bgp;
 	data->mode = THERMAL_DEVICE_ENABLED;
+	data->pcb_tz = thermal_zone_get_zone_by_name("pcb");
 	INIT_WORK(&data->thermal_wq, ti_thermal_work);
 
 	return data;