Re: [PATCH v3] thermal: imx8mm_thermal: validate temperature range

From: Peng Fan
Date: Mon Oct 17 2022 - 04:06:38 EST




On 10/14/2022 3:35 PM, Marcus Folkesson wrote:
Check against the upper temperature limit (125 degrees C) before
consider the temperature valid.

Fixes: 5eed800a6811 ("thermal: imx8mm: Add support for i.MX8MM thermal monitoring unit")
Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
---

Notes:
v2: Also invalidate if temperature > max (125 degrees C)
v3: Only check temperature range as the valid bit is invalid.

drivers/thermal/imx8mm_thermal.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/imx8mm_thermal.c b/drivers/thermal/imx8mm_thermal.c
index af666bd9e8d4..c5cd873c6e01 100644
--- a/drivers/thermal/imx8mm_thermal.c
+++ b/drivers/thermal/imx8mm_thermal.c
@@ -65,8 +65,14 @@ static int imx8mm_tmu_get_temp(void *data, int *temp)
u32 val;
val = readl_relaxed(tmu->base + TRITSR) & TRITSR_TEMP0_VAL_MASK;
+
+ /*
+ * Do not validate against the V bit (bit 31) due to errata
+ * ERR051272: TMU: Bit 31 of registers TMU_TSCR/TMU_TRITSR/TMU_TRATSR invalid
+ */
+
*temp = val * 1000;
- if (*temp < VER1_TEMP_LOW_LIMIT)
+ if (*temp < VER1_TEMP_LOW_LIMIT || *temp > VER2_TEMP_HIGH_LIMIT)
return -EAGAIN;
return 0;

Reviewed-by: Peng Fan <peng.fan@xxxxxxx>