# SPDX-License-Identifier: GPL-2.0-only
#
# I2C subsystem configuration
#
menu "I2C support"
config I2C
tristate "I2C support"
select RT_MUTEXES
select IRQ_DOMAIN
help
I2C (pronounce: I-squared-C) is a slow serial bus protocol used in
many micro controller applications and developed by Philips. SMBus,
or System Management Bus is a subset of the I2C protocol. More
information is contained in the directory <file:Documentation/i2c/>,
especially in the file called "summary" there.
Both I2C and SMBus are supported here. You will need this for
hardware sensors support, and also for Video For Linux support.
If you want I2C support, you should say Y here and also to the
specific driver for your bus adapter(s) below.
This I2C support can also be built as a module. If so, the module
will be called i2c-core.
config ACPI_I2C_OPREGION
bool "ACPI I2C Operation region support"
depends on I2C=y && ACPI
default y
help
Say Y here if you want to enable ACPI I2C operation region support.
Operation Regions allow firmware (BIOS) code to access I2C slave devices,
such as smart batteries through an I2C host controller driver.
if I2C
config I2C_BOARDINFO
bool
default y
config I2C_COMPAT
bool "Enable compatibility bits for old user-space"
default y
help
Say Y here if you intend to run lm-sensors 3.1.1 or older, or any
other user-space package which expects i2c adapters to be class
devices. If you don't know, say Y.
config I2C_CHARDEV
tristate "I2C device interface"
help
Say Y here to use i2c-* device files, usually found in the /dev
directory on your system. They make it possible to have user-space
programs use the I2C bus. Information on how to do this is
contained in the file <file:Documentation/i2c/dev-interface.rst>.
This support is also available as a module. If so, the module
will be called i2c-dev.
config I2C_MUX
tristate "I2C bus multiplexing support"
help
Say Y here if you want the I2C core to support the ability to
handle multiplexed I2C bus topologies, by presenting each
multiplexed segment as a I2C adapter.
This support is also available as a module. If so, the module
will be called i2c-mux.
source "drivers/i2c/muxes/Kconfig"
config I2C_HELPER_AUTO
bool "Autoselect pertinent helper modules"
default y
help
Some I2C bus drivers require so-called "I2C algorithm" modules
to work. These are basically software-only abstractions of generic
I2C interfaces. This option will autoselect them so that you don't
have to care.
Unselect this only if you need to enable additional helper
modules, for example for use with external I2C bus drivers.
In doubt, say Y.
config I2C_SMBUS
tristate "SMBus-specific protocols" if !I2C_HELPER_AUTO
help
Say Y here if you want support for SMBus extensions to the I2C
specification. At the moment, two extensions are supported:
the SMBus Alert protocol and the SMBus Host Notify protocol.
This support is also available as a module. If so, the module
will be called i2c-smbus.
source "drivers/i2c/algos/Kconfig"
source "drivers/i2c/busses/Kconfig"
config I2C_STUB
tristate "I2C/SMBus Test Stub"
depends on m
default 'n'
help
This module may be useful to developers of SMBus client drivers,
especially for certain kinds of sensor chips.
If you do build this module, be sure to read the notes and warnings
in <file:Documentation/i2c/i2c-stub.rst>.
If you don't know what to do here, definitely say N.
config I2C_SLAVE
bool "I2C slave support"
help
This enables Linux to act as an I2C slave device. Note that your I2C
bus master driver also needs to support this functionality. Please
read Documentation/i2c/slave-interface.rst for further details.
if I2C_SLAVE
config I2C_SLAVE_EEPROM
tristate "I2C eeprom slave driver"
help
This backend makes Linux behave like an I2C EEPROM. Please read
Documentation/i2c/slave-eeprom-backend.rst for further details.
endif
config I2C_DEBUG_CORE
bool "I2C Core debugging messages"
help
Say Y here if you want the I2C core to produce a bunch of debug
messages to the system log. Select this if you are having a
problem with I2C support and want to see more of what is going on.
config I2C_DEBUG_ALGO
bool "I2C Algorithm debugging messages"
help
Say Y here if you want the I2C algorithm drivers to produce a bunch
of debug messages to the system log. Select this if you are having
a problem with I2C support and want to see more of what is going
on.
config I2C_DEBUG_BUS
bool "I2C Bus debugging messages"
depends on HAS_IOMEM
help
Say Y here if you want the I2C bus drivers to produce a bunch of
debug messages to the system log. Select this if you are having
a problem with I2C support and want to see more of what is going
on.
endif # I2C
endmenu
