1 # SPDX-License-Identifier: GPL-2.0-only 2 # 3 # I2C subsystem configuration 4 # 5 6 menu "I2C support" 7 8 config 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 28 config 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 37 if I2C 38 39 config I2C_BOARDINFO 40 bool 41 default y 42 43 config 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 54 config 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 64 source "drivers/i2c/muxes/Kconfig" 65 66 config 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 75 config 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 89 config 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 99 source "drivers/i2c/algos/Kconfig" 100 source "drivers/i2c/busses/Kconfig" 101 102 config 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. 113 114 config 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. 120 121 if I2C_SLAVE 122 123 config 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. 128 129 config 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. 136 137 endif 138 139 config 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. 145 146 config 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. 153 154 config 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. 162 163 endif # I2C 164 165 endmenu 166