On Tue, Jul 16, 2019 at 08:19:04PM +0200, Maximilian Luz wrote:

Hi,

On 7/16/19 9:21 AM, Dmitry Torokhov wrote:

quoted

When you are saying that Pro 4 and later models use different
notifications, does this mean that Pro 4 does not define any GPIOs?

Unfortunately, at least the Surface Book (first generation, buttons are
handled the same way as on the Pro 4) has GPIOs defined in MSHW0040, but
they are for different use. Specifically: They can detect if the
clipboard (screen part of the device, the device basically has two parts
that can be separated: clipboard and base) is being removed. Relying on
the GPIOs was my first idea too, but that has been reported to shut down
the Book 1 when the clipboard is detached.

As far as I know, the OEM platform revision check is the easiest way to
differentiate between those devices.

OK, fair enough. By the way, I see you are adding some #ifdef
CONFIG_ACPI and stubbing out new functions, but the driver does not
really work without ACPI (acpi_match_device() will fail in this case I
would think and that will cause probe() to abort). So maybe we just add
depends on ACPI to the driver's Kconfig entry?

Thanks.

-- 
Dmitry