[PATCH 3/4] thermal: stm32: fix engineering calibration value

From: Pascal Paillet
Date: Tue Oct 29 2019 - 12:46:13 EST


TS1_T0 is only used by engineering during calibration.
The temperature offset is actually fixed to 30 Celsius.

Signed-off-by: Pascal Paillet <p.paillet@xxxxxx>
Change-Id: I83abea65ff3f58f8954256495f2d5d38f0d868d9
---
drivers/thermal/st/stm_thermal.c | 22 ++++++----------------
1 file changed, 6 insertions(+), 16 deletions(-)

diff --git a/drivers/thermal/st/stm_thermal.c b/drivers/thermal/st/stm_thermal.c
index 4bc1bbece0de..37abbdffe573 100644
--- a/drivers/thermal/st/stm_thermal.c
+++ b/drivers/thermal/st/stm_thermal.c
@@ -82,8 +82,7 @@
#define ONE_MHZ 1000000
#define POLL_TIMEOUT 5000
#define STARTUP_TIME 40
-#define TS1_T0_VAL0 30000 /* 30 celsius */
-#define TS1_T0_VAL1 130000 /* 130 celsius */
+#define T0 30000 /* 30 celsius */
#define NO_HW_TRIG 0
#define SAMPLING_TIME 15

@@ -94,7 +93,7 @@ struct stm_thermal_sensor {
struct clk *clk;
int irq;
void __iomem *base;
- int t0, fmt0, ramp_coeff;
+ int fmt0, ramp_coeff;
int low_en, high_en;
};

@@ -248,14 +247,6 @@ static int stm_thermal_calibration(struct stm_thermal_sensor *sensor)
/* Fill in DTS structure with factory sensor values */
static int stm_thermal_read_factory_settings(struct stm_thermal_sensor *sensor)
{
- /* Retrieve engineering calibration temperature */
- sensor->t0 = readl_relaxed(sensor->base + DTS_T0VALR1_OFFSET) &
- TS1_T0_MASK;
- if (!sensor->t0)
- sensor->t0 = TS1_T0_VAL0;
- else
- sensor->t0 = TS1_T0_VAL1;
-
/* Retrieve fmt0 and put it on Hz */
sensor->fmt0 = ADJUST * (readl_relaxed(sensor->base +
DTS_T0VALR1_OFFSET) & TS1_FMT0_MASK);
@@ -269,8 +260,8 @@ static int stm_thermal_read_factory_settings(struct stm_thermal_sensor *sensor)
return -EINVAL;
}

- dev_dbg(sensor->dev, "%s: T0 = %doC, FMT0 = %dHz, RAMP_COEFF = %dHz/oC",
- __func__, sensor->t0, sensor->fmt0, sensor->ramp_coeff);
+ dev_dbg(sensor->dev, "%s: FMT0 = %dHz, RAMP_COEFF = %dHz/oC",
+ __func__, sensor->fmt0, sensor->ramp_coeff);

return 0;
}
@@ -281,8 +272,7 @@ static int stm_thermal_calculate_threshold(struct stm_thermal_sensor *sensor,
int freqM;

/* Figure out the CLK_PTAT frequency for a given temperature */
- freqM = ((temp - sensor->t0) * sensor->ramp_coeff) / 1000 +
- sensor->fmt0;
+ freqM = ((temp - T0) * sensor->ramp_coeff) / 1000 + sensor->fmt0;

/* Figure out the threshold sample number */
*th = clk_get_rate(sensor->clk) * SAMPLING_TIME / freqM;
@@ -317,7 +307,7 @@ static int stm_thermal_get_temp(void *data, int *temp)
return -EINVAL;

/* Figure out the temperature in mili celsius */
- *temp = (freqM - sensor->fmt0) * 1000 / sensor->ramp_coeff + sensor->t0;
+ *temp = (freqM - sensor->fmt0) * 1000 / sensor->ramp_coeff + T0;

dev_dbg(sensor->dev, "periods=0x%x t=%d mC", periods, *temp);

--
2.17.1