RE: [PATCH v3] Support intel-vbtn based tablet mode switch

From: Mario.Limonciello
Date: Tue Jan 23 2018 - 09:52:13 EST


> -----Original Message-----
> From: platform-driver-x86-owner@xxxxxxxxxxxxxxx [mailto:platform-driver-x86-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Marco Martin
> Sent: Tuesday, January 23, 2018 6:42 AM
> To: linux-kernel@xxxxxxxxxxxxxxx
> Cc: mjg59@xxxxxxxxxxxxx; pali.rohar@xxxxxxxxx; dvhart@xxxxxxxxxxxxx;
> andy@xxxxxxxxxxxxx; bhush94@xxxxxxxxx; platform-driver-x86@xxxxxxxxxxxxxxx;
> Limonciello, Mario <Mario_Limonciello@xxxxxxxx>; Marco Martin
> <notmart@xxxxxxxxx>; Limonciello, Mario <Mario_Limonciello@xxxxxxxx>
> Subject: [PATCH v3] Support intel-vbtn based tablet mode switch
>
> Some laptops such as Dell Inspiron 7000 series have the
> tablet mode switch implemented in Intel ACPI,
> the events to enter and exit the tablet mode are 0xCC and 0xCD
>
> CC: platform-driver-x86@xxxxxxxxxxxxxxx
> CC: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
> CC: "Pali RohÃr" <pali.rohar@xxxxxxxxx>
> CC: Darren Hart <dvhart@xxxxxxxxxxxxx>
> CC: Mario Limonciello <mario_limonciello@xxxxxxxx>
> CC: Andy Shevchenko <andy@xxxxxxxxxxxxx>
>
> Signed-off-by: Marco Martin <notmart@xxxxxxxxx>
> ---
> drivers/platform/x86/intel-vbtn.c | 21 +++++++++++++++++++++
> 1 file changed, 21 insertions(+)
>
> diff --git a/drivers/platform/x86/intel-vbtn.c b/drivers/platform/x86/intel-vbtn.c
> index 58c5ff3..64b4b34 100644
> --- a/drivers/platform/x86/intel-vbtn.c
> +++ b/drivers/platform/x86/intel-vbtn.c
> @@ -26,6 +26,9 @@
> #include <linux/suspend.h>
> #include <acpi/acpi_bus.h>
>
> +/* When NOT in tablet mode, VBDS has the flag 0x40 */
> +#define TABLET_MODE_FLAG 0x40

Minor typographical error here, you mean VGBS output
not VDBS right?

VDBS may be implementation specific, you're explicitly
looking at VGBS.

> +
> MODULE_LICENSE("GPL");
> MODULE_AUTHOR("AceLan Kao");
>
> @@ -42,6 +45,8 @@ static const struct key_entry intel_vbtn_keymap[] = {
> { KE_IGNORE, 0xC5, { KEY_VOLUMEUP } }, /* volume-up key
> release */
> { KE_KEY, 0xC6, { KEY_VOLUMEDOWN } }, /* volume-down
> key press */
> { KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } }, /* volume-down key
> release */
> + { KE_SW, 0xCC, { .sw = { SW_TABLET_MODE, 1 } } }, /* Tablet mode in */
> + { KE_SW, 0xCD, { .sw = { SW_TABLET_MODE, 0 } } }, /* Tablet mode out */
> { KE_END },
> };
>
> @@ -88,6 +93,7 @@ static void notify_handler(acpi_handle handle, u32 event,
> void *context)
>
> static int intel_vbtn_probe(struct platform_device *device)
> {
> + struct acpi_buffer vgbs_output = { ACPI_ALLOCATE_BUFFER, NULL };
> acpi_handle handle = ACPI_HANDLE(&device->dev);
> struct intel_vbtn_priv *priv;
> acpi_status status;
> @@ -110,6 +116,21 @@ static int intel_vbtn_probe(struct platform_device
> *device)
> return err;
> }
>
> + status = acpi_evaluate_object(handle, "VGBS", NULL, &vgbs_output);
> + /* VGBS being present and returning something means
> + * we have a tablet mode switch
> + */
> + if (ACPI_SUCCESS(status)) {
> + union acpi_object *obj = vgbs_output.pointer;
> +
> + if (obj && obj->type == ACPI_TYPE_INTEGER) {
> + input_set_capability(priv->input_dev, EV_SW,
> SW_TABLET_MODE);
> + input_report_switch(priv->input_dev,
> +
> SW_TABLET_MODE,
> + !(obj-
> >integer.value & TABLET_MODE_FLAG));
> + }
> + }
> +
> status = acpi_install_notify_handler(handle,
> ACPI_DEVICE_NOTIFY,
> notify_handler,
> --
> 2.7.4