Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
62 lines
1.7 KiB
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62 lines
1.7 KiB
ReStructuredText
.. 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 (in the scope of \_SB)::
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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, "\\_SB.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, "\\_SB.SMB1.MUX0.CH00",
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0x00, 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, "\\_SB.SMB1.MUX0.CH01",
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0x00, 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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