xref: /freebsd/share/man/man4/man4.i386/glxiic.4 (revision 02e9120893770924227138ba49df1edb3896112a)
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24.Dd May 15, 2011
25.Dt GLXIIC 4 i386
26.Os
27.Sh NAME
28.Nm glxiic
29.Nd Geode LX CS5536 I2C controller driver
30.Sh SYNOPSIS
31To compile this driver into the kernel,
32place the following lines in your
33kernel configuration file:
34.Bd -ragged -offset indent
35.Cd "device pci"
36.Cd "device isa"
37.Cd "device glxiic"
38.Cd "device iicbus"
39.Ed
40.Pp
41Alternatively, to load the driver as a
42module at boot time, place the following line in
43.Xr loader.conf 5 :
44.Bd -literal -offset indent
45glxiic_load="YES"
46.Ed
47.Sh DESCRIPTION
48The
49.Nm
50driver supports the System Management Bus controller of the Geode LX
51series CS5536 Companion Device.
52The Geode LX is a member of the AMD Geode family of integrated x86 system chips.
53.Pp
54Although AMD refers to this device as a System Management Bus (SMBus)
55controller, it is really an I2C controller (it lacks SMBus ALERT# and
56Alert Response support).
57.Pp
58The
59.Nm
60driver supports both I2C master and slave mode.
61.Sh SYSCTL VARIABLE
62The
63.Nm
64driver supports the following variable as both
65.Xr sysctl 8
66and
67.Xr loader 8
68tunable:
69.Bl -tag -width indent
70.It Va dev.glxiic.0.timeout
71This variable controls the I2C bus timeout in milliseconds.
72The default timeout is 35 milliseconds.
73A value of zero disables the timeout.
74.El
75.Sh CAVEAT
76The
77.Nm
78driver uses the interrupt line number configured by the board firmware
79by default.
80If no interrupt line number has been configured by the board firmware
81(or to override the interrupt line number configured by board firmware),
82place the following line in
83.Xr device.hints 5 :
84.Bd -ragged -offset indent
85hint.glxiic.0.irq="10"
86.Ed
87.Pp
88The interrupt line number must be between 1 and 15.
89.Sh SEE ALSO
90.Xr iicbus 4 ,
91.Xr device.hints 5 ,
92.Xr loader.conf 5 ,
93.Xr loader 8 ,
94.Xr sysctl 8
95.Sh HISTORY
96The
97.Nm
98device driver and manual page first appeared in
99.Fx 9.0 .
100.Sh AUTHORS
101.An -nosplit
102The
103.Nm
104device driver and manual page were written by
105.An Henrik Brix Andersen Aq Mt brix@FreeBSD.org .
106