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a430556ecb
Add an i2c mux driver providing access to i2c bus segments using a
hardware MUX sitting on a master bus and controlled through gpio pins.
E.G. something like:
---------- ---------- Bus segment 1 - - - - -
| | SCL/SDA | |-------------- | |
| |------------| |
| | | | Bus segment 2 | |
| Linux | GPIO 1..N | MUX |--------------- Devices
| |------------| | | |
| | | | Bus segment M
| | | |---------------| |
---------- ---------- - - - - -
SCL/SDA of the master I2C bus is multiplexed to bus segment 1..M
according to the settings of the GPIO pins 1..N.
Note commit log from kernel
commit 92ed1a76("i2c: Add generic I2C multiplexer using GPIO API")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Tested-by: Peng Fan <peng.fan@nxp.com> (i.MX6QP-Sabreauto)
Cc: Heiko Schocher <hs@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Simon Glass <sjg@chromium.org>
45 lines
1.6 KiB
Text
45 lines
1.6 KiB
Text
config I2C_MUX
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bool "Support I2C multiplexers"
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depends on DM_I2C
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help
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This enables I2C buses to be multiplexed, so that you can select
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one of several buses using some sort of control mechanism. The
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bus select is handled automatically when that bus is accessed,
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using a suitable I2C MUX driver.
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config SPL_I2C_MUX
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bool "Support I2C multiplexers on SPL"
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depends on I2C_MUX
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help
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This enables I2C buses to be multiplexed, so that you can select
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one of several buses using some sort of control mechanism. The
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bus select is handled automatically when that bus is accessed,
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using a suitable I2C MUX driver.
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config I2C_ARB_GPIO_CHALLENGE
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bool "GPIO-based I2C arbitration"
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depends on I2C_MUX
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help
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If you say yes to this option, support will be included for an
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I2C multimaster arbitration scheme using GPIOs and a challenge &
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response mechanism where masters have to claim the bus by asserting
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a GPIO.
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config I2C_MUX_PCA954x
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tristate "TI PCA954x I2C Mux/switches"
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depends on I2C_MUX
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help
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If you say yes here you get support for the TI PCA954x
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I2C mux/switch devices. It is x width I2C multiplexer which enables to
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paritioning I2C bus and connect multiple devices with the same address
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to the same I2C controller where driver handles proper routing to
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target i2c device. PCA9544 and PCA9548 are supported.
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config I2C_MUX_GPIO
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tristate "GPIO-based I2C multiplexer"
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depends on I2C_MUX && DM_GPIO
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help
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If you say yes to this option, support will be included for
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a GPIO based I2C multiplexer. This driver provides access to
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I2C busses connected through a MUX, which is controlled
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through GPIO pins.
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