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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-10 09:15:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-10 09:15:46 -0700
commit190a3998be3ede25d6145e187d6d321f504d28fb (patch)
treead5d6ec7d701b2af054e4922502810908226c0d3 /drivers/thermal
parent4162877d3ffa900b618c369c490c7faa6af60e47 (diff)
parent9477165ec525d47abb1cb6523698e0cd89d65ddb (diff)
downloadlinux-190a3998be3ede25d6145e187d6d321f504d28fb.tar.gz
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal management updates from Zhang Rui:
 "We only have a couple of fixes/cleanups for platform thermal drivers
  this time.

  Specifics:

   - rcar thermal driver: avoid updating the thermal zone in case an IRQ
     was triggered but the temperature didn't effectively change.  From
     Patrick Titiano.

   - update the imx thermal driver' formula of converting thermal
     sensor' raw date to real temperature in degree C.  From Anson
     Huang.

   - trivial code cleanups of ti soc thermal and rcar thermal driver
     from Jingoo Han and Patrick Titiano"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  thermal: rcar-thermal: update thermal zone only when temperature changes
  thermal: rcar-thermal: fix same mask applied twice
  thermal: ti-soc-thermal: Use SIMPLE_DEV_PM_OPS macro
  thermal: imx: update formula for thermal sensor
Diffstat (limited to 'drivers/thermal')
-rw-r--r--drivers/thermal/imx_thermal.c39
-rw-r--r--drivers/thermal/rcar_thermal.c9
-rw-r--r--drivers/thermal/ti-soc-thermal/ti-bandgap.c6
3 files changed, 35 insertions, 19 deletions
diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
index 45af765a3198..a99c63152b8d 100644
--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -62,12 +62,16 @@ enum imx_thermal_trip {
 #define IMX_POLLING_DELAY		2000 /* millisecond */
 #define IMX_PASSIVE_DELAY		1000
 
+#define FACTOR0				10000000
+#define FACTOR1				15976
+#define FACTOR2				4297157
+
 struct imx_thermal_data {
 	struct thermal_zone_device *tz;
 	struct thermal_cooling_device *cdev;
 	enum thermal_device_mode mode;
 	struct regmap *tempmon;
-	int c1, c2; /* See formula in imx_get_sensor_data() */
+	u32 c1, c2; /* See formula in imx_get_sensor_data() */
 	unsigned long temp_passive;
 	unsigned long temp_critical;
 	unsigned long alarm_temp;
@@ -84,7 +88,7 @@ static void imx_set_alarm_temp(struct imx_thermal_data *data,
 	int alarm_value;
 
 	data->alarm_temp = alarm_temp;
-	alarm_value = (alarm_temp - data->c2) / data->c1;
+	alarm_value = (data->c2 - alarm_temp) / data->c1;
 	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
 	regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
 			TEMPSENSE0_ALARM_VALUE_SHIFT);
@@ -136,7 +140,7 @@ static int imx_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
 	n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;
 
 	/* See imx_get_sensor_data() for formula derivation */
-	*temp = data->c2 + data->c1 * n_meas;
+	*temp = data->c2 - n_meas * data->c1;
 
 	/* Update alarm value to next higher trip point */
 	if (data->alarm_temp == data->temp_passive && *temp >= data->temp_passive)
@@ -305,6 +309,7 @@ static int imx_get_sensor_data(struct platform_device *pdev)
 	int t1, t2, n1, n2;
 	int ret;
 	u32 val;
+	u64 temp64;
 
 	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 					      "fsl,tempmon-data");
@@ -330,6 +335,8 @@ static int imx_get_sensor_data(struct platform_device *pdev)
 	 *   [31:20] - sensor value @ 25C
 	 *    [19:8] - sensor value of hot
 	 *     [7:0] - hot temperature value
+	 * Use universal formula now and only need sensor value @ 25C
+	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
 	 */
 	n1 = val >> 20;
 	n2 = (val & 0xfff00) >> 8;
@@ -337,20 +344,26 @@ static int imx_get_sensor_data(struct platform_device *pdev)
 	t1 = 25; /* t1 always 25C */
 
 	/*
-	 * Derived from linear interpolation,
-	 * Tmeas = T2 + (Nmeas - N2) * (T1 - T2) / (N1 - N2)
+	 * Derived from linear interpolation:
+	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
+	 * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
+	 * (Nmeas - n1) / (Tmeas - t1) = slope
 	 * We want to reduce this down to the minimum computation necessary
 	 * for each temperature read.  Also, we want Tmeas in millicelsius
 	 * and we don't want to lose precision from integer division. So...
-	 * milli_Tmeas = 1000 * T2 + 1000 * (Nmeas - N2) * (T1 - T2) / (N1 - N2)
-	 * Let constant c1 = 1000 * (T1 - T2) / (N1 - N2)
-	 * milli_Tmeas = (1000 * T2) + c1 * (Nmeas - N2)
-	 * milli_Tmeas = (1000 * T2) + (c1 * Nmeas) - (c1 * N2)
-	 * Let constant c2 = (1000 * T2) - (c1 * N2)
-	 * milli_Tmeas = c2 + (c1 * Nmeas)
+	 * Tmeas = (Nmeas - n1) / slope + t1
+	 * milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
+	 * milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
+	 * Let constant c1 = (-1000 / slope)
+	 * milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
+	 * Let constant c2 = n1 *c1 + 1000 * t1
+	 * milli_Tmeas = c2 - Nmeas * c1
 	 */
-	data->c1 = 1000 * (t1 - t2) / (n1 - n2);
-	data->c2 = 1000 * t2 - data->c1 * n2;
+	temp64 = FACTOR0;
+	temp64 *= 1000;
+	do_div(temp64, FACTOR1 * n1 - FACTOR2);
+	data->c1 = temp64;
+	data->c2 = n1 * data->c1 + 1000 * t1;
 
 	/*
 	 * Set the default passive cooling trip point to 20 °C below the
diff --git a/drivers/thermal/rcar_thermal.c b/drivers/thermal/rcar_thermal.c
index 79a09d02bbca..5a37940b02c9 100644
--- a/drivers/thermal/rcar_thermal.c
+++ b/drivers/thermal/rcar_thermal.c
@@ -299,12 +299,17 @@ static void _rcar_thermal_irq_ctrl(struct rcar_thermal_priv *priv, int enable)
 static void rcar_thermal_work(struct work_struct *work)
 {
 	struct rcar_thermal_priv *priv;
+	unsigned long cctemp, nctemp;
 
 	priv = container_of(work, struct rcar_thermal_priv, work.work);
 
+	rcar_thermal_get_temp(priv->zone, &cctemp);
 	rcar_thermal_update_temp(priv);
 	rcar_thermal_irq_enable(priv);
-	thermal_zone_device_update(priv->zone);
+
+	rcar_thermal_get_temp(priv->zone, &nctemp);
+	if (nctemp != cctemp)
+		thermal_zone_device_update(priv->zone);
 }
 
 static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
@@ -313,7 +318,7 @@ static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
 
 	status = (status >> rcar_id_to_shift(priv)) & 0x3;
 
-	if (status & 0x3) {
+	if (status) {
 		dev_dbg(dev, "thermal%d %s%s\n",
 			priv->id,
 			(status & 0x2) ? "Rising " : "",
diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.c b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
index 74c0e3474d6e..3ab12ee359b7 100644
--- a/drivers/thermal/ti-soc-thermal/ti-bandgap.c
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
@@ -1500,10 +1500,8 @@ static int ti_bandgap_resume(struct device *dev)
 
 	return ti_bandgap_restore_ctxt(bgp);
 }
-static const struct dev_pm_ops ti_bandgap_dev_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(ti_bandgap_suspend,
-				ti_bandgap_resume)
-};
+static SIMPLE_DEV_PM_OPS(ti_bandgap_dev_pm_ops, ti_bandgap_suspend,
+			 ti_bandgap_resume);
 
 #define DEV_PM_OPS	(&ti_bandgap_dev_pm_ops)
 #else