thermal: stm32: Disable interrupts at probe

In case of CPU reset, the interrupts could be enabled at boot time.
Disable interrupts and clear flags.

Signed-off-by: Pascal Paillet <p.paillet@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200110101605.24984-4-p.paillet@st.com

drivers/thermal/st/stm_thermal.c

@@ -51,6 +51,12 @@
 /* DTS_DR register mask definitions */
 #define TS1_MFREQ_MASK		GENMASK(15, 0)
 
+/* DTS_ITENR register mask definitions */
+#define ITENR_MASK		(GENMASK(2, 0) | GENMASK(6, 4))
+
+/* DTS_ICIFR register mask definitions */
+#define ICIFR_MASK		(GENMASK(2, 0) | GENMASK(6, 4))
+
 /* Less significant bit position definitions */
 #define TS1_T0_POS		16
 #define TS1_SMP_TIME_POS	16
@@ -330,12 +336,10 @@ static int stm_disable_irq(struct stm_thermal_sensor *sensor)
 {
 	u32 value;
 
-	/* Disable IT generation for low and high thresholds */
+	/* Disable IT generation */
 	value = readl_relaxed(sensor->base + DTS_ITENR_OFFSET);
-	writel_relaxed(value & ~(LOW_THRESHOLD | HIGH_THRESHOLD),
-		       sensor->base + DTS_ITENR_OFFSET);
-
-	dev_dbg(sensor->dev, "%s: IT disabled on sensor side", __func__);
+	value &= ~ITENR_MASK;
+	writel_relaxed(value, sensor->base + DTS_ITENR_OFFSET);
 
 	return 0;
 }
@@ -645,6 +649,11 @@ static int stm_thermal_probe(struct platform_device *pdev)
 		return PTR_ERR(sensor->clk);
 	}
 
+	stm_disable_irq(sensor);
+
+	/* Clear irq flags */
+	writel_relaxed(ICIFR_MASK, sensor->base + DTS_ICIFR_OFFSET);
+
 	/* Register IRQ into GIC */
 	ret = stm_register_irq(sensor);
 	if (ret)