Add identifiers in ACPI tables for GPIO based I2C multiplexer. The
multiplexer device defines the GPIO resource used to select the
adapter/bus lines. The multiplexer adapter device defines the address
to select the adapter/client lines. These ACPI identifiers are consumed
by the i2c-mux-gpio kernel driver:
https://www.kernel.org/doc/html/latest/i2c/muxes/i2c-mux-gpio.html
BUG=b:169444894
TEST=Build and boot waddledee to OS. Ensure that the ACPI identifiers
are added for I2C devices multiplexed using I2C MUX under the
appropriate scope. Here is the output SSDT:
Scope (\_SB.PCI0.I2C3)
{
Device (MUX0)
{
Name (_HID, "PRP0001") // _HID: Hardware ID
Method (_STA, 0, NotSerialized) // _STA: Status
{
Return (0x0F)
}
Name (_CRS, ResourceTemplate () // _CRS: Current Resource Settings
{
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly,
"\\_SB.PCI0.GPIO", 0x00, ResourceConsumer, ,
)
{ // Pin list
0x0125
}
})
Name (_DSD, Package (0x02) // _DSD: Device-Specific Data
{
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /* Device Properties for _DSD */,
Package (0x02)
{
Package (0x02)
{
"compatible",
"i2c-mux-gpio"
},
Package (0x02)
{
"mux-gpios",
Package (0x04)
{
\_SB.PCI0.I2C3.MUX0,
Zero,
Zero,
Zero
}
}
}
})
}
}
Change-Id: Ib371108cc6043c133681066bf7bf4b2e00771e8b
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45911
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
