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linux/drivers/i2c/Kconfig
David Brownell 9c1600eda4 i2c: Add i2c_board_info and i2c_new_device()
This provides partial support for new-style I2C driver binding.  It builds
on "struct i2c_board_info" declarations that identify I2C devices on a given
board.  This is needed on systems with I2C devices that can't be fully probed
and/or autoconfigured, such as many embedded Linux configurations where the
way a given I2C device is wired may affect how it must be used.

There are two models for declaring such devices:

 * LATE -- using a public function i2c_new_device().  This lets modules
   declare I2C devices found *AFTER* a given I2C adapter becomes available.
   
   For example, a PCI card could create adapters giving access to utility
   chips on that card, and this would be used to associate those chips with
   those adapters.

 * EARLY -- from arch_initcall() level code, using a non-exported function
   i2c_register_board_info().  This copies the declarations *BEFORE* such
   an i2c_adapter becomes available, arranging that i2c_new_device() will
   be called later when i2c-core registers the relevant i2c_adapter.

   For example, arch/.../.../board-*.c files would declare the I2C devices
   along with their platform data, and I2C devices would behave much like
   PNPACPI devices.  (That is, both enumerate from board-specific tables.)

To match the exported i2c_new_device(), the previously-private function
i2c_unregister_device() is now exported.

Pending later patches using these new APIs, this is effectively a NOP.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 23:26:31 +02:00

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#
# I2C subsystem configuration
#
menu "I2C support"
config I2C
tristate "I2C support"
---help---
I2C (pronounce: I-square-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 I2C_BOARDINFO
boolean
depends on I2C
default y
config I2C_CHARDEV
tristate "I2C device interface"
depends on I2C
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>.
This support is also available as a module. If so, the module
will be called i2c-dev.
source drivers/i2c/algos/Kconfig
source drivers/i2c/busses/Kconfig
source drivers/i2c/chips/Kconfig
config I2C_DEBUG_CORE
bool "I2C Core debugging messages"
depends on I2C
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"
depends on I2C
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 I2C
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.
config I2C_DEBUG_CHIP
bool "I2C Chip debugging messages"
depends on I2C
help
Say Y here if you want the I2C chip 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.
endmenu