62 lines
1.7 KiB
ReStructuredText
62 lines
1.7 KiB
ReStructuredText
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.. SPDX-License-Identifier: GPL-2.0
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==============
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ACPI I2C Muxes
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==============
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Describing an I2C device hierarchy that includes I2C muxes requires an ACPI
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Device () scope per mux channel.
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Consider this topology::
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+------+ +------+
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| SMB1 |-->| MUX0 |--CH00--> i2c client A (0x50)
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| | | 0x70 |--CH01--> i2c client B (0x50)
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+------+ +------+
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which corresponds to the following ASL::
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Device (SMB1)
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{
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Name (_HID, ...)
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Device (MUX0)
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{
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Name (_HID, ...)
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Name (_CRS, ResourceTemplate () {
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I2cSerialBus (0x70, ControllerInitiated, I2C_SPEED,
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AddressingMode7Bit, "^SMB1", 0x00,
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ResourceConsumer,,)
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}
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Device (CH00)
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{
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Name (_ADR, 0)
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Device (CLIA)
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{
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Name (_HID, ...)
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Name (_CRS, ResourceTemplate () {
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I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED,
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AddressingMode7Bit, "^CH00", 0x00,
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ResourceConsumer,,)
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}
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}
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}
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Device (CH01)
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{
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Name (_ADR, 1)
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Device (CLIB)
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{
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Name (_HID, ...)
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Name (_CRS, ResourceTemplate () {
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I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED,
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AddressingMode7Bit, "^CH01", 0x00,
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ResourceConsumer,,)
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}
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}
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}
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}
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}
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