75 lines
2.3 KiB
ReStructuredText
75 lines
2.3 KiB
ReStructuredText
Kernel driver max6650
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=====================
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Supported chips:
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* Maxim MAX6650
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Prefix: 'max6650'
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Addresses scanned: none
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Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
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* Maxim MAX6651
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Prefix: 'max6651'
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Addresses scanned: none
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Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
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Authors:
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- Hans J. Koch <hjk@hansjkoch.de>
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- John Morris <john.morris@spirentcom.com>
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- Claus Gindhart <claus.gindhart@kontron.com>
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Description
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-----------
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This driver implements support for the Maxim MAX6650 and MAX6651.
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The 2 devices are very similar, but the MAX6550 has a reduced feature
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set, e.g. only one fan-input, instead of 4 for the MAX6651.
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The driver is not able to distinguish between the 2 devices.
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The driver provides the following sensor accesses in sysfs:
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=============== ======= =======================================================
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fan1_input ro fan tachometer speed in RPM
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fan2_input ro "
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fan3_input ro "
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fan4_input ro "
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fan1_target rw desired fan speed in RPM (closed loop mode only)
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pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop
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3=off
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pwm1 rw relative speed (0-255), 255=max. speed.
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Used in open loop mode only.
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fan1_div rw sets the speed range the inputs can handle. Legal
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values are 1, 2, 4, and 8. Use lower values for
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faster fans.
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=============== ======= =======================================================
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Usage notes
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-----------
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This driver does not auto-detect devices. You will have to instantiate the
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devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for
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details.
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Module parameters
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-----------------
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If your board has a BIOS that initializes the MAX6650/6651 correctly, you can
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simply load your module without parameters. It won't touch the configuration
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registers then. If your board BIOS doesn't initialize the chip, or you want
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different settings, you can set the following parameters:
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voltage_12V: 5=5V fan, 12=12V fan, 0=don't change
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prescaler: Possible values are 1,2,4,8,16, or 0 for don't change
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clock: The clock frequency in Hz of the chip the driver should assume [254000]
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Please have a look at the MAX6650/6651 data sheet and make sure that you fully
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understand the meaning of these parameters before you attempt to change them.
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