xref: /linux/Documentation/i2c/busses/i2c-viapro.rst (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1========================
2Kernel driver i2c-viapro
3========================
4
5Supported adapters:
6  * VIA Technologies, Inc. VT82C596A/B
7    Datasheet: Sometimes available at the VIA website
8
9  * VIA Technologies, Inc. VT82C686A/B
10    Datasheet: Sometimes available at the VIA website
11
12  * VIA Technologies, Inc. VT8231, VT8233, VT8233A
13    Datasheet: available on request from VIA
14
15  * VIA Technologies, Inc. VT8235, VT8237R, VT8237A, VT8237S, VT8251
16    Datasheet: available on request and under NDA from VIA
17
18  * VIA Technologies, Inc. CX700
19    Datasheet: available on request and under NDA from VIA
20
21  * VIA Technologies, Inc. VX800/VX820
22    Datasheet: available on http://linux.via.com.tw
23
24  * VIA Technologies, Inc. VX855/VX875
25    Datasheet: available on http://linux.via.com.tw
26
27  * VIA Technologies, Inc. VX900
28    Datasheet: available on http://linux.via.com.tw
29
30Authors:
31	- Kyösti Mälkki <kmalkki@cc.hut.fi>,
32	- Mark D. Studebaker <mdsxyz123@yahoo.com>,
33	- Jean Delvare <jdelvare@suse.de>
34
35Module Parameters
36-----------------
37
38* force: int
39  Forcibly enable the SMBus controller. DANGEROUS!
40* force_addr: int
41  Forcibly enable the SMBus at the given address. EXTREMELY DANGEROUS!
42
43Description
44-----------
45
46i2c-viapro is a true SMBus host driver for motherboards with one of the
47supported VIA south bridges.
48
49Your ``lspci -n`` listing must show one of these :
50
51 ================   ======================
52 device 1106:3050   (VT82C596A function 3)
53 device 1106:3051   (VT82C596B function 3)
54 device 1106:3057   (VT82C686 function 4)
55 device 1106:3074   (VT8233)
56 device 1106:3147   (VT8233A)
57 device 1106:8235   (VT8231 function 4)
58 device 1106:3177   (VT8235)
59 device 1106:3227   (VT8237R)
60 device 1106:3337   (VT8237A)
61 device 1106:3372   (VT8237S)
62 device 1106:3287   (VT8251)
63 device 1106:8324   (CX700)
64 device 1106:8353   (VX800/VX820)
65 device 1106:8409   (VX855/VX875)
66 device 1106:8410   (VX900)
67 ================   ======================
68
69If none of these show up, you should look in the BIOS for settings like
70enable ACPI / SMBus or even USB.
71
72Except for the oldest chips (VT82C596A/B, VT82C686A and most probably
73VT8231), this driver supports I2C block transactions. Such transactions
74are mainly useful to read from and write to EEPROMs.
75
76The CX700/VX800/VX820 additionally appears to support SMBus PEC, although
77this driver doesn't implement it yet.
78