From 2d7a548a3eff382da5cd743670693b7657327714 Mon Sep 17 00:00:00 2001 From: Jaghathiswari Rankappagounder Natarajan Date: Tue, 4 Apr 2017 17:52:41 -0700 Subject: drivers: hwmon: Support for ASPEED PWM/Fan tach The ASPEED AST2400/2500 PWM controller supports 8 PWM output ports. The ASPEED AST2400/2500 Fan tach controller supports 16 tachometer inputs. The device driver matches on the device tree node. The configuration values are read from the device tree and written to the respective registers. The driver provides a sysfs entries through which the user can configure the duty-cycle value (ranging from 0 to 100 percent) and read the fan tach rpm value. Signed-off-by: Jaghathiswari Rankappagounder Natarajan Signed-off-by: Guenter Roeck --- Documentation/hwmon/aspeed-pwm-tacho | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 Documentation/hwmon/aspeed-pwm-tacho (limited to 'Documentation/hwmon') diff --git a/Documentation/hwmon/aspeed-pwm-tacho b/Documentation/hwmon/aspeed-pwm-tacho new file mode 100644 index 000000000000..7cfb34977460 --- /dev/null +++ b/Documentation/hwmon/aspeed-pwm-tacho @@ -0,0 +1,22 @@ +Kernel driver aspeed-pwm-tacho +============================== + +Supported chips: + ASPEED AST2400/2500 + +Authors: + + +Description: +------------ +This driver implements support for ASPEED AST2400/2500 PWM and Fan Tacho +controller. The PWM controller supports upto 8 PWM outputs. The Fan tacho +controller supports up to 16 tachometer inputs. + +The driver provides the following sensor accesses in sysfs: + +fanX_input ro provide current fan rotation value in RPM as reported + by the fan to the device. + +pwmX rw get or set PWM fan control value. This is an integer + value between 0(off) and 255(full speed). -- cgit v1.2.3-59-g8ed1b