[RFC PATCH v3 0/2] hwmon: emc2305: Support configurable fan PWM at shutdown
From: florin . leotescu
Date: Thu Mar 12 2026 - 10:33:54 EST
From: Florin Leotescu <florin.leotescu@xxxxxxx>
This series adds support for configuring the fan PWM duty cycle applied
during system shutdown for the EMC2305 fan controller.
Some platforms require fans to transition to a predefined safe state
during shutdown or reboot handoff until firmware or the next boot stage
reconfigures the controller.
The new optional Device Tree property "fan-shutdown-percent" allows the
shutdown PWM duty cycle to be configured per fan output.
Changes in v3:
- Rebased on current upstream
- Dropped already upstreamed of_node_put(child) fix
Changes in v2:
- Address feedback from Guenter Roeck
- Make shutdown behavior configurable via Device Tree
- Add optional fan-shutdown-percent property
- Apply shutdown PWM only for channels defining the property
Florin Leotescu (2):
dt-bindings: hwmon: emc2305: Add fan-shutdown-percent property
hwmon: emc2305: Support configurable fan PWM at shutdown
.../bindings/hwmon/microchip,emc2305.yaml | 8 +++++
drivers/hwmon/emc2305.c | 34 +++++++++++++++++++
2 files changed, 42 insertions(+)
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2.34.1