xref: /linux/Documentation/misc-devices/ics932s401.rst (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
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2Kernel driver ics932s401
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4
5Supported chips:
6
7  * IDT ICS932S401
8
9    Prefix: 'ics932s401'
10
11    Addresses scanned: I2C 0x69
12
13    Datasheet: Publicly available at the IDT website
14
15Author: Darrick J. Wong
16
17Description
18-----------
19
20This driver implements support for the IDT ICS932S401 chip family.
21
22This chip has 4 clock outputs--a base clock for the CPU (which is likely
23multiplied to get the real CPU clock), a system clock, a PCI clock, a USB
24clock, and a reference clock.  The driver reports selected and actual
25frequency.  If spread spectrum mode is enabled, the driver also reports by what
26percent the clock signal is being spread, which should be between 0 and -0.5%.
27All frequencies are reported in KHz.
28
29The ICS932S401 monitors all inputs continuously. The driver will not read
30the registers more often than once every other second.
31
32Special Features
33----------------
34
35The clocks could be reprogrammed to increase system speed.  I will not help you
36do this, as you risk damaging your system!
37