Re: [PATCH V6 5/8] vfio: platform: call _RST method when using ACPI

[Rafael J. Wysocki]

On Sun, May 29, 2016 at 12:01 AM, Sinan Kaya <okaya@xxxxxxxxxxxxxx> wrote:
> The device tree code checks for the presence of a reset driver and calls
> the of_reset function pointer by looking up the reset driver as a module.
>
> ACPI defines _RST method to perform device level reset. After the _RST
> method is executed, the OS can resume using the device. _RST method is
> expected to stop DMA transfers and IRQs.
>
> This patch checks the presence of _RST method and calls the _RST
> method when reset is requested.

You could check if _RST is present at probe time and store the ACPI
handle of it instead of the HID pointer.

This way you wouldn't need to repeat that check every time reset is used.