linux/Documentation/hwmon/emc2305.rst

.. SPDX-License-Identifier: GPL-2.0

Kernel driver emc2305
=====================

Supported chips:
   Microchip EMC2305, EMC2303, EMC2302, EMC2301

   Addresses scanned: I2C 0x27, 0x2c, 0x2d, 0x2e, 0x2f, 0x4c, 0x4d
   Prefixes: 'emc2305'

   Datasheet: Publicly available at the Microchip website :
      https://www.microchip.com/en-us/product/EMC2305

Description:
------------
This driver implements support for Microchip EMC2301/2/3/5 RPM-based PWM Fan Controller.
The EMC2305 Fan Controller supports up to 5 independently controlled PWM fan drives.
Fan rotation speeds are reported in RPM.
The driver supports the RPM-based PWM control to keep a fan at the desired speed.
The driver provides the possibility to have one common PWM interface for all FANs
or up to the maximum available or configured independent PWMs.

The driver provides the following sysfs interfaces in hwmon subsystem:

================= == ===================================================
fan[1-5]_fault    RO files for tachometers TACH1-TACH5 fault indication
fan[1-5]_input    RO files for tachometers TACH1-TACH5 input (in RPM)
pwm[1-5]          RW file for fan[1-5] target duty cycle (0..255)
================= == ===================================================

sysfs interfaces in thermal subsystem:

================= == ========================================================================
cur_state         RW file for the current cooling state of the cooling device (0..max_state)
max_state         RO file for the maximum cooling state of the cooling device
================= == ========================================================================