1# SPDX-License-Identifier: GPL-2.0-only
2#
3# I2C subsystem configuration
4#
5
6menu "I2C support"
7
8config I2C
9	tristate "I2C support"
10	select RT_MUTEXES
11	select IRQ_DOMAIN
12	help
13	  I2C (pronounce: I-squared-C) is a slow serial bus protocol used in
14	  many micro controller applications and developed by Philips.  SMBus,
15	  or System Management Bus is a subset of the I2C protocol.  More
16	  information is contained in the directory <file:Documentation/i2c/>,
17	  especially in the file called "summary" there.
18
19	  Both I2C and SMBus are supported here. You will need this for
20	  hardware sensors support, and also for Video For Linux support.
21
22	  If you want I2C support, you should say Y here and also to the
23	  specific driver for your bus adapter(s) below.
24
25	  This I2C support can also be built as a module.  If so, the module
26	  will be called i2c-core.
27
28config ACPI_I2C_OPREGION
29	bool "ACPI I2C Operation region support"
30	depends on I2C=y && ACPI
31	default y
32	help
33	  Say Y here if you want to enable ACPI I2C operation region support.
34	  Operation Regions allow firmware (BIOS) code to access I2C slave devices,
35	  such as smart batteries through an I2C host controller driver.
36
37if I2C
38
39config I2C_BOARDINFO
40	bool
41	default y
42
43config I2C_CHARDEV
44	tristate "I2C device interface"
45	help
46	  Say Y here to use i2c-* device files, usually found in the /dev
47	  directory on your system.  They make it possible to have user-space
48	  programs use the I2C bus.  Information on how to do this is
49	  contained in the file <file:Documentation/i2c/dev-interface.rst>.
50
51	  This support is also available as a module.  If so, the module
52	  will be called i2c-dev.
53
54config I2C_MUX
55	tristate "I2C bus multiplexing support"
56	help
57	  Say Y here if you want the I2C core to support the ability to
58	  handle multiplexed I2C bus topologies, by presenting each
59	  multiplexed segment as a I2C adapter.
60
61	  This support is also available as a module.  If so, the module
62	  will be called i2c-mux.
63
64source "drivers/i2c/muxes/Kconfig"
65
66config I2C_ATR
67	tristate "I2C Address Translator (ATR) support" if COMPILE_TEST
68	help
69	  Enable support for I2C Address Translator (ATR) chips.
70
71	  An ATR allows accessing multiple I2C busses from a single
72	  physical bus via address translation instead of bus selection as
73	  i2c-muxes do.
74
75config I2C_HELPER_AUTO
76	bool "Autoselect pertinent helper modules"
77	default y
78	help
79	  Some I2C bus drivers require so-called "I2C algorithm" modules
80	  to work. These are basically software-only abstractions of generic
81	  I2C interfaces. This option will autoselect them so that you don't
82	  have to care.
83
84	  Unselect this only if you need to enable additional helper
85	  modules, for example for use with external I2C bus drivers.
86
87	  In doubt, say Y.
88
89config I2C_SMBUS
90	tristate "SMBus-specific protocols" if !I2C_HELPER_AUTO
91	help
92	  Say Y here if you want support for SMBus extensions to the I2C
93	  specification. At the moment, two extensions are supported:
94	  the SMBus Alert protocol and the SMBus Host Notify protocol.
95
96	  This support is also available as a module.  If so, the module
97	  will be called i2c-smbus.
98
99source "drivers/i2c/algos/Kconfig"
100source "drivers/i2c/busses/Kconfig"
101
102config I2C_STUB
103	tristate "I2C/SMBus Test Stub"
104	depends on m
105	help
106	  This module may be useful to developers of SMBus client drivers,
107	  especially for certain kinds of sensor chips.
108
109	  If you do build this module, be sure to read the notes and warnings
110	  in <file:Documentation/i2c/i2c-stub.rst>.
111
112	  If you don't know what to do here, definitely say N.
113
114config I2C_SLAVE
115	bool "I2C slave support"
116	help
117	  This enables Linux to act as an I2C slave device. Note that your I2C
118	  bus master driver also needs to support this functionality. Please
119	  read Documentation/i2c/slave-interface.rst for further details.
120
121if I2C_SLAVE
122
123config I2C_SLAVE_EEPROM
124	tristate "I2C eeprom slave driver"
125	help
126	  This backend makes Linux behave like an I2C EEPROM. Please read
127	  Documentation/i2c/slave-eeprom-backend.rst for further details.
128
129config I2C_SLAVE_TESTUNIT
130	tristate "I2C testunit driver"
131	help
132	  This backend can be used to trigger test cases for I2C bus masters
133	  which require a remote device with certain capabilities, e.g.
134	  multi-master, SMBus Host Notify, etc. Please read
135	  Documentation/i2c/slave-testunit-backend.rst for further details.
136
137endif
138
139config I2C_DEBUG_CORE
140	bool "I2C Core debugging messages"
141	help
142	  Say Y here if you want the I2C core to produce a bunch of debug
143	  messages to the system log.  Select this if you are having a
144	  problem with I2C support and want to see more of what is going on.
145
146config I2C_DEBUG_ALGO
147	bool "I2C Algorithm debugging messages"
148	help
149	  Say Y here if you want the I2C algorithm drivers to produce a bunch
150	  of debug messages to the system log.  Select this if you are having
151	  a problem with I2C support and want to see more of what is going
152	  on.
153
154config I2C_DEBUG_BUS
155	bool "I2C Bus debugging messages"
156	depends on HAS_IOMEM
157	help
158	  Say Y here if you want the I2C bus drivers to produce a bunch of
159	  debug messages to the system log.  Select this if you are having
160	  a problem with I2C support and want to see more of what is going
161	  on.
162
163endif # I2C
164
165endmenu
166