[PATCH 2/2] staging: ti-soc-thermal: remove external heat while extrapolating hotspot

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



For boards that provide a PCB sensor close to SoC junction
temperature, it is possible to remove the cumulative heat
reported by the SoC temperature sensor.

This patch changes the extrapolation computation to consider
an external sensor in the extrapolation equations.

Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxx>
---
 drivers/staging/ti-soc-thermal/ti-thermal-common.c | 30 ++++++++++++++--------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/ti-soc-thermal/ti-thermal-common.c b/drivers/staging/ti-soc-thermal/ti-thermal-common.c
index e3c5e67..8e67ebf 100644
--- a/drivers/staging/ti-soc-thermal/ti-thermal-common.c
+++ b/drivers/staging/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;
-- 
1.8.2.1.342.gfa7285d

--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux