mirror of https://github.com/torvalds/linux.git
40 lines
1.3 KiB
ReStructuredText
40 lines
1.3 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
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Kernel driver kfan
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==================
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Supported chips:
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* KEBA fan controller (IP core in FPGA)
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Prefix: 'kfan'
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Authors:
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Gerhard Engleder <eg@keba.com>
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Petar Bojanic <boja@keba.com>
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Description
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-----------
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The KEBA fan controller is an IP core for FPGAs, which monitors the health
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and controls the speed of a fan. The fan is typically used to cool the CPU
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and the whole device. E.g., the CP500 FPGA includes this IP core to monitor
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and control the fan of PLCs and the corresponding cp500 driver creates an
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auxiliary device for the kfan driver.
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This driver provides information about the fan health to user space.
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The user space shall be informed if the fan is removed or blocked.
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Additionally, the speed in RPM is reported for fans with tacho signal.
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For fan control PWM is supported. For PWM 255 equals 100%. None-regulable
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fans can be turned on with PWM 255 and turned off with PWM 0.
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====================== ==== ===================================================
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Attribute R/W Contents
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====================== ==== ===================================================
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fan1_fault R Fan fault
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fan1_input R Fan tachometer input (in RPM)
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pwm1 RW Fan target duty cycle (0..255)
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====================== ==== ===================================================
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