[PATCH] thermal/drivers/airoha: Fix FIELD_PREP using wrong mask for sensor interval

Wayen.Yan win847 at gmail.com
Sat Jun 13 17:14:28 PDT 2026


In airoha_thermal_setup_monitor(), the TEMPMONCTL2 register is
programmed with:

  writel(FIELD_PREP(EN7581_FILT_INTERVAL, 1) |
         FIELD_PREP(EN7581_FILT_INTERVAL, 379), ...)

Both FIELD_PREP calls target FILT_INTERVAL (GENMASK(25,16)), so the
second one overwrites the first. The sensor interval field
SEN_INTERVAL (GENMASK(9,0)) is never written and remains zero.

The comment above states: "filt interval is 1 * 52.715us, sen interval
is 379 * 52.715us", confirming the second value should go into
SEN_INTERVAL. This matches the Mediatek auxadc_thermal.c reference
implementation which correctly writes FILTER_INTERVAL and
SENSOR_INTERVAL to their respective non-overlapping bit fields.

Actual effect: FILT=379 (should be 1), SEN=0 (should be 379).
The filter interval runs 379x too long and the sensor sampling
interval is uninitialized, causing incorrect thermal monitoring timing.

Fix by replacing the second FIELD_PREP's mask from FILT_INTERVAL to
SEN_INTERVAL.

Fixes: 42de37f40e1b ("thermal/drivers: Add support for Airoha EN7581 thermal sensor")
Signed-off-by: Wayen <win847 at gmail.com>
---
 drivers/thermal/airoha_thermal.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thermal/airoha_thermal.c b/drivers/thermal/airoha_thermal.c
index b9fd6bfc88..e8a33234e0 100644
--- a/drivers/thermal/airoha_thermal.c
+++ b/drivers/thermal/airoha_thermal.c
@@ -403,7 +403,7 @@ static void airoha_thermal_setup_monitor(struct airoha_thermal_priv *priv)
 	 * sen interval is 379 * 52.715us = 19.97ms
 	 */
 	writel(FIELD_PREP(EN7581_FILT_INTERVAL, 1) |
-	       FIELD_PREP(EN7581_FILT_INTERVAL, 379),
+	       FIELD_PREP(EN7581_SEN_INTERVAL, 379),
 	       priv->base + EN7581_TEMPMONCTL2);
 
 	/* AHB poll is set to 146 * 68.64 = 10.02us */
-- 
2.51.0





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