Re: [PATCH V7 5/7] ACPI: Delay the enumeration on the devices whose dependency has not met

From: Rafael J. Wysocki
Date: Mon Mar 13 2017 - 17:30:16 EST


On Monday, March 13, 2017 10:42:41 AM zhichang.yuan wrote:
> In commit 40e7fcb1929(ACPI: Add _DEP support to fix battery issue on Asus
> T100TA), the '_DEP' was supported to solve the dependency of Asus battery. But
> this patch is specific to Asus battery device.
> In the real world, there are other devices which need the dependency to play the
> role on the enumeration order. For example, all the Hip06 LPC
> periperals(IPMI-BT, uart, etc) must be scanned after the LPC host driver
> finished the probing. So, it makes sense to add a checking whether the ACPI
> device meet all the dependencies during its enumeration slot, if not, the
> enumeration will be delayed till all dependency master finish their work.
>
> This patch adds the dependency checking in ACPI enumeration, also the
> corresponding handling to retrigger the Hip06 LPC peripherals' scanning.

AFAICS, _DEP is generally abused in the wild and cannot be made generic. Sorry.

Thanks,
Rafael