mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 02:30:34 +02:00
f13d483eaf
Use the new i2c_acpi_client_count() helper, this results in a nice cleanup. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20210803160044.158802-3-hdegoede@redhat.com
52 lines
1.7 KiB
C
52 lines
1.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Helper code to detect 360 degree hinges (yoga) style 2-in-1 devices using 2 accelerometers
|
|
* to allow the OS to determine the angle between the display and the base of the device.
|
|
*
|
|
* On Windows these are read by a special HingeAngleService process which calls undocumented
|
|
* ACPI methods, to let the firmware know if the 2-in-1 is in tablet- or laptop-mode.
|
|
* The firmware may use this to disable the kbd and touchpad to avoid spurious input in
|
|
* tablet-mode as well as to report SW_TABLET_MODE info to the OS.
|
|
*
|
|
* Since Linux does not call these undocumented methods, the SW_TABLET_MODE info reported
|
|
* by various drivers/platform/x86 drivers is incorrect. These drivers use the detection
|
|
* code in this file to disable SW_TABLET_MODE reporting to avoid reporting broken info
|
|
* (instead userspace can derive the status itself by directly reading the 2 accels).
|
|
*/
|
|
|
|
#include <linux/acpi.h>
|
|
#include <linux/i2c.h>
|
|
|
|
static bool dual_accel_detect_bosc0200(void)
|
|
{
|
|
struct acpi_device *adev;
|
|
int count;
|
|
|
|
adev = acpi_dev_get_first_match_dev("BOSC0200", NULL, -1);
|
|
if (!adev)
|
|
return false;
|
|
|
|
count = i2c_acpi_client_count(adev);
|
|
|
|
acpi_dev_put(adev);
|
|
|
|
return count == 2;
|
|
}
|
|
|
|
static bool dual_accel_detect(void)
|
|
{
|
|
/* Systems which use a pair of accels with KIOX010A / KIOX020A ACPI ids */
|
|
if (acpi_dev_present("KIOX010A", NULL, -1) &&
|
|
acpi_dev_present("KIOX020A", NULL, -1))
|
|
return true;
|
|
|
|
/* Systems which use a single DUAL250E ACPI device to model 2 accels */
|
|
if (acpi_dev_present("DUAL250E", NULL, -1))
|
|
return true;
|
|
|
|
/* Systems which use a single BOSC0200 ACPI device to model 2 accels */
|
|
if (dual_accel_detect_bosc0200())
|
|
return true;
|
|
|
|
return false;
|
|
}
|