[PATCH] hwmon: (dell-smm) Add Dell Precision 3650 Tower to fan control whitelist
From: Patrick Pepin
Date: Sun Sep 13 2026 - 07:30:34 EST
On the Dell Precision 3650 Tower, the EC ignores fan speed writes unless
automatic BIOS fan control is disabled first. The same SMM code pair as
the OptiPlex 7000 (I8K_FAN_34A3_35A3) works on this machine through the
WMI-SMM backend: after writing 1 to pwm1_enable, all three fans (CPU,
front, top) accept the three fan states and report matching RPM.
Tested on BIOS 1.48.0 with kernels 7.0.0-30 and 7.0.0-31 (Ubuntu 26.04).
Signed-off-by: Patrick Pepin <patpep@xxxxxx>
---
drivers/hwmon/dell-smm-hwmon.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index 7ed94a3db..47668634f 100644
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -1639,6 +1639,14 @@ static const struct dmi_system_id i8k_whitelist_fan_control[] __initconst = {
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
+ {
+ .ident = "Dell Precision 3650 Tower",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+ DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 3650 Tower"),
+ },
+ .driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
+ },
{
.ident = "Dell Optiplex 7090",
.matches = {
--
2.53.0