[XS] Change in coreboot[master]: mb/google/rex/var/rex0: Change touch over spi interrupt trigger to edge

[Eran Mitrani (Code Review)]

Attention is currently required from: Eric Lai, Jakub Czapiga, Kapil Porwal, Tarun Tuli.

Eran Mitrani has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/76116?usp=email )

Change subject: mb/google/rex/var/rex0: Change touch over spi interrupt trigger to edge
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Patch Set 3:

(1 comment)

File src/mainboard/google/rex/variants/rex0/include/variant/acpi/hid_spi_elan.asl:

https://review.coreboot.org/c/coreboot/+/76116/comment/86dc36dc_de0cd9af :
PS3, Line 42: Edge
> For I2C mode, it's level. Wondering why level not working here.

It is mentioned in the hid over spi spec here: https://www.microsoft.com/en-us/download/details.aspx?id=103325:
"HID SPI peripheral must provide a dedicated falling (HIGH-TO-LOW) edge triggered interrupt line to indicate when data or status is ready. This interrupt line must be pulled HIGH by hardware otherwise, meeting both HOST and DEVICE electrical requirements"