From 653ef165247824be27e900ab28d1f8aa74c09604 Mon Sep 17 00:00:00 2001 From: Michael Shych Date: Sat, 30 Apr 2022 14:49:05 +0300 Subject: [PATCH] docs: hwmon: add emc2305.rst to docs Submitted to linux-hwmon mailing list at https://patchwork.kernel.org/project/linux-hwmon/patch/20220430114905.53448-4-michaelsh@nvidia.com/ Add description of emc2305 driver. Signed-off-by: Michael Shych Reviewed-by: Vadim Pasternak --- Documentation/hwmon/emc2305.rst | 40 +++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 Documentation/hwmon/emc2305.rst --- /dev/null +++ b/Documentation/hwmon/emc2305.rst @@ -0,0 +1,40 @@ +.. 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 +================= == ======================================================================== + +Configuration is possible via device tree: +Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml