On 3/29/24 7:32 AM, Gwendal Grignou wrote:
> ACER Vivobook Flip (TP401NAS) virtual intel switch is implemented as
> follow:
>
> Device (VGBI)
> {
> Name (_HID, EisaId ("INT33D6") ...
> Name (VBDS, Zero)
> Method (_STA, 0, Serialized) // _STA: Status ...
> Method (VBDL, 0, Serialized)
> {
> PB1E |= 0x20
> VBDS |= 0x40
> }
> Method (VGBS, 0, Serialized)
> {
> Return (VBDS) /* \_SB_.PCI0.SBRG.EC0_.VGBI.VBDS */
> }
> ...
> }
>
> By default VBDS is set to 0. At boot it is set to clamshell (bit 6 set)
> only after method VBDL is executed.
>
> Since VBDL is now evaluated in the probe routine later, after the device
> is registered, the retrieved value of VBDS was still 0 ("tablet mode")
> when setting up the virtual switch.
>
> Make sure to evaluate VGBS after VBDL, to ensure the
> convertible boots in clamshell mode, the expected default.
>
> Fixes: 26173179fae1 ("platform/x86: intel-vbtn: Eval VBDL after registering our notifier")
> Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> ---
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> drivers/platform/x86/intel/vbtn.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/x86/intel/vbtn.c b/drivers/platform/x86/intel/vbtn.c
> index 48f0ac19d6ddf..79bb2c801daa9 100644
> --- a/drivers/platform/x86/intel/vbtn.c
> +++ b/drivers/platform/x86/intel/vbtn.c
> @@ -136,8 +136,6 @@ static int intel_vbtn_input_setup(struct platform_device *device)
> priv->switches_dev->id.bustype = BUS_HOST;
>
> if (priv->has_switches) {
> - detect_tablet_mode(&device->dev);
> -
> ret = input_register_device(priv->switches_dev);
> if (ret)
> return ret;
> @@ -312,6 +310,9 @@ static int intel_vbtn_probe(struct platform_device *device)
> if (ACPI_FAILURE(status))
> dev_err(&device->dev, "Error VBDL failed with ACPI status %d\n", status);
> }
> + // Check switches after buttons since VBDL may have side effects.
> + if (has_switches)
> + detect_tablet_mode(&device->dev);
>
> device_init_wakeup(&device->dev, true);
> /*
--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer
