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_COMPAT 44 bool "Enable compatibility bits for old user-space" 45 default y 46 help 47 Say Y here if you intend to run lm-sensors 3.1.1 or older, or any 48 other user-space package which expects i2c adapters to be class 49 devices. If you don't know, say Y. 50 51config I2C_CHARDEV 52 tristate "I2C device interface" 53 help 54 Say Y here to use i2c-* device files, usually found in the /dev 55 directory on your system. They make it possible to have user-space 56 programs use the I2C bus. Information on how to do this is 57 contained in the file <file:Documentation/i2c/dev-interface.rst>. 58 59 This support is also available as a module. If so, the module 60 will be called i2c-dev. 61 62config I2C_MUX 63 tristate "I2C bus multiplexing support" 64 help 65 Say Y here if you want the I2C core to support the ability to 66 handle multiplexed I2C bus topologies, by presenting each 67 multiplexed segment as a I2C adapter. 68 69 This support is also available as a module. If so, the module 70 will be called i2c-mux. 71 72source "drivers/i2c/muxes/Kconfig" 73 74config I2C_ATR 75 tristate "I2C Address Translator (ATR) support" 76 help 77 Enable support for I2C Address Translator (ATR) chips. 78 79 An ATR allows accessing multiple I2C busses from a single 80 physical bus via address translation instead of bus selection as 81 i2c-muxes do. 82 83config I2C_HELPER_AUTO 84 bool "Autoselect pertinent helper modules" 85 default y 86 help 87 Some I2C bus drivers require so-called "I2C algorithm" modules 88 to work. These are basically software-only abstractions of generic 89 I2C interfaces. This option will autoselect them so that you don't 90 have to care. 91 92 Unselect this only if you need to enable additional helper 93 modules, for example for use with external I2C bus drivers. 94 95 In doubt, say Y. 96 97config I2C_SMBUS 98 tristate "SMBus-specific protocols" if !I2C_HELPER_AUTO 99 help 100 Say Y here if you want support for SMBus extensions to the I2C 101 specification. At the moment, two extensions are supported: 102 the SMBus Alert protocol and the SMBus Host Notify protocol. 103 104 This support is also available as a module. If so, the module 105 will be called i2c-smbus. 106 107source "drivers/i2c/algos/Kconfig" 108source "drivers/i2c/busses/Kconfig" 109 110config I2C_STUB 111 tristate "I2C/SMBus Test Stub" 112 depends on m 113 help 114 This module may be useful to developers of SMBus client drivers, 115 especially for certain kinds of sensor chips. 116 117 If you do build this module, be sure to read the notes and warnings 118 in <file:Documentation/i2c/i2c-stub.rst>. 119 120 If you don't know what to do here, definitely say N. 121 122config I2C_SLAVE 123 bool "I2C slave support" 124 help 125 This enables Linux to act as an I2C slave device. Note that your I2C 126 bus master driver also needs to support this functionality. Please 127 read Documentation/i2c/slave-interface.rst for further details. 128 129if I2C_SLAVE 130 131config I2C_SLAVE_EEPROM 132 tristate "I2C eeprom slave driver" 133 help 134 This backend makes Linux behave like an I2C EEPROM. Please read 135 Documentation/i2c/slave-eeprom-backend.rst for further details. 136 137config I2C_SLAVE_TESTUNIT 138 tristate "I2C eeprom testunit driver" 139 help 140 This backend can be used to trigger test cases for I2C bus masters 141 which require a remote device with certain capabilities, e.g. 142 multi-master, SMBus Host Notify, etc. Please read 143 Documentation/i2c/slave-testunit-backend.rst for further details. 144 145endif 146 147config I2C_DEBUG_CORE 148 bool "I2C Core debugging messages" 149 help 150 Say Y here if you want the I2C core to produce a bunch of debug 151 messages to the system log. Select this if you are having a 152 problem with I2C support and want to see more of what is going on. 153 154config I2C_DEBUG_ALGO 155 bool "I2C Algorithm debugging messages" 156 help 157 Say Y here if you want the I2C algorithm drivers to produce a bunch 158 of debug messages to the system log. Select this if you are having 159 a problem with I2C support and want to see more of what is going 160 on. 161 162config I2C_DEBUG_BUS 163 bool "I2C Bus debugging messages" 164 depends on HAS_IOMEM 165 help 166 Say Y here if you want the I2C bus drivers to produce a bunch of 167 debug messages to the system log. Select this if you are having 168 a problem with I2C support and want to see more of what is going 169 on. 170 171endif # I2C 172 173endmenu 174