xref: /openbmc/linux/Documentation/i2c/busses/i2c-viapro.rst (revision 976e3645923bdd2fe7893aae33fd7a21098bfb28)
1*ccf988b6SMauro Carvalho Chehab========================
2*ccf988b6SMauro Carvalho ChehabKernel driver i2c-viapro
3*ccf988b6SMauro Carvalho Chehab========================
4*ccf988b6SMauro Carvalho Chehab
5*ccf988b6SMauro Carvalho ChehabSupported adapters:
6*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VT82C596A/B
7*ccf988b6SMauro Carvalho Chehab    Datasheet: Sometimes available at the VIA website
8*ccf988b6SMauro Carvalho Chehab
9*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VT82C686A/B
10*ccf988b6SMauro Carvalho Chehab    Datasheet: Sometimes available at the VIA website
11*ccf988b6SMauro Carvalho Chehab
12*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VT8231, VT8233, VT8233A
13*ccf988b6SMauro Carvalho Chehab    Datasheet: available on request from VIA
14*ccf988b6SMauro Carvalho Chehab
15*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VT8235, VT8237R, VT8237A, VT8237S, VT8251
16*ccf988b6SMauro Carvalho Chehab    Datasheet: available on request and under NDA from VIA
17*ccf988b6SMauro Carvalho Chehab
18*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. CX700
19*ccf988b6SMauro Carvalho Chehab    Datasheet: available on request and under NDA from VIA
20*ccf988b6SMauro Carvalho Chehab
21*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VX800/VX820
22*ccf988b6SMauro Carvalho Chehab    Datasheet: available on http://linux.via.com.tw
23*ccf988b6SMauro Carvalho Chehab
24*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VX855/VX875
25*ccf988b6SMauro Carvalho Chehab    Datasheet: available on http://linux.via.com.tw
26*ccf988b6SMauro Carvalho Chehab
27*ccf988b6SMauro Carvalho Chehab  * VIA Technologies, Inc. VX900
28*ccf988b6SMauro Carvalho Chehab    Datasheet: available on http://linux.via.com.tw
29*ccf988b6SMauro Carvalho Chehab
30*ccf988b6SMauro Carvalho ChehabAuthors:
31*ccf988b6SMauro Carvalho Chehab	- Kyösti Mälkki <kmalkki@cc.hut.fi>,
32*ccf988b6SMauro Carvalho Chehab	- Mark D. Studebaker <mdsxyz123@yahoo.com>,
33*ccf988b6SMauro Carvalho Chehab	- Jean Delvare <jdelvare@suse.de>
34*ccf988b6SMauro Carvalho Chehab
35*ccf988b6SMauro Carvalho ChehabModule Parameters
36*ccf988b6SMauro Carvalho Chehab-----------------
37*ccf988b6SMauro Carvalho Chehab
38*ccf988b6SMauro Carvalho Chehab* force: int
39*ccf988b6SMauro Carvalho Chehab  Forcibly enable the SMBus controller. DANGEROUS!
40*ccf988b6SMauro Carvalho Chehab* force_addr: int
41*ccf988b6SMauro Carvalho Chehab  Forcibly enable the SMBus at the given address. EXTREMELY DANGEROUS!
42*ccf988b6SMauro Carvalho Chehab
43*ccf988b6SMauro Carvalho ChehabDescription
44*ccf988b6SMauro Carvalho Chehab-----------
45*ccf988b6SMauro Carvalho Chehab
46*ccf988b6SMauro Carvalho Chehabi2c-viapro is a true SMBus host driver for motherboards with one of the
47*ccf988b6SMauro Carvalho Chehabsupported VIA south bridges.
48*ccf988b6SMauro Carvalho Chehab
49*ccf988b6SMauro Carvalho ChehabYour ``lspci -n`` listing must show one of these :
50*ccf988b6SMauro Carvalho Chehab
51*ccf988b6SMauro Carvalho Chehab ================   ======================
52*ccf988b6SMauro Carvalho Chehab device 1106:3050   (VT82C596A function 3)
53*ccf988b6SMauro Carvalho Chehab device 1106:3051   (VT82C596B function 3)
54*ccf988b6SMauro Carvalho Chehab device 1106:3057   (VT82C686 function 4)
55*ccf988b6SMauro Carvalho Chehab device 1106:3074   (VT8233)
56*ccf988b6SMauro Carvalho Chehab device 1106:3147   (VT8233A)
57*ccf988b6SMauro Carvalho Chehab device 1106:8235   (VT8231 function 4)
58*ccf988b6SMauro Carvalho Chehab device 1106:3177   (VT8235)
59*ccf988b6SMauro Carvalho Chehab device 1106:3227   (VT8237R)
60*ccf988b6SMauro Carvalho Chehab device 1106:3337   (VT8237A)
61*ccf988b6SMauro Carvalho Chehab device 1106:3372   (VT8237S)
62*ccf988b6SMauro Carvalho Chehab device 1106:3287   (VT8251)
63*ccf988b6SMauro Carvalho Chehab device 1106:8324   (CX700)
64*ccf988b6SMauro Carvalho Chehab device 1106:8353   (VX800/VX820)
65*ccf988b6SMauro Carvalho Chehab device 1106:8409   (VX855/VX875)
66*ccf988b6SMauro Carvalho Chehab device 1106:8410   (VX900)
67*ccf988b6SMauro Carvalho Chehab ================   ======================
68*ccf988b6SMauro Carvalho Chehab
69*ccf988b6SMauro Carvalho ChehabIf none of these show up, you should look in the BIOS for settings like
70*ccf988b6SMauro Carvalho Chehabenable ACPI / SMBus or even USB.
71*ccf988b6SMauro Carvalho Chehab
72*ccf988b6SMauro Carvalho ChehabExcept for the oldest chips (VT82C596A/B, VT82C686A and most probably
73*ccf988b6SMauro Carvalho ChehabVT8231), this driver supports I2C block transactions. Such transactions
74*ccf988b6SMauro Carvalho Chehabare mainly useful to read from and write to EEPROMs.
75*ccf988b6SMauro Carvalho Chehab
76*ccf988b6SMauro Carvalho ChehabThe CX700/VX800/VX820 additionally appears to support SMBus PEC, although
77*ccf988b6SMauro Carvalho Chehabthis driver doesn't implement it yet.
78