Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

Pull input updates from Dmitry Torokhov:

 - input core allows hardware drivers to specify a [more precise]
   timestamp (normally taken in top half) to better track velocity of
   contacts

 - input_dev instances now support "polling" mode so that drivers could
   use the same object for polled and interrupt-driven operation. The
   plan is to convert existing drivers and retire input_polled_dev API

 - a new driver for the FlySky FS-iA6B RC receiver

 - a refresh of BU21013 touchpad driver

 - w90x900 keyboard and touchpad drivers are removed as the platform is
   gone

 - assorted fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (45 commits)
  Input: sidewinder - make array seq static const, makes object smaller
  Input: reset device timestamp on sync
  Input: bu21013_ts - switch to using standard touchscreen properties
  Input: bu21013_ts - switch to using MT-B (slotted) protocol
  Input: bu21013_ts - fix suspend when wake source
  Input: bu21013_ts - use interrupt from I2C client
  Input: bu21013_ts - remove support for platform data
  Input: bu21013_ts - convert to using managed resources
  Input: bu21013_ts - remove useless comments
  Input: bu21013_ts - annotate supend/resume methods as __maybe_unused
  Input: bu21013_ts - rename some variables
  Input: bu21013_ts - convert to use GPIO descriptors
  ARM: ux500: improve BU21013 touchpad bindings
  Input: i8042 - enable wakeup on a stable struct device
  Input: soc_button_array - use platform_device_register_resndata()
  Input: psmouse - drop all unneeded functions from mouse headers
  Input: add support for polling to input devices
  Input: wacom_w8001 - allocate additional space for 'phys'
  Input: cros_ec_keyb - add back missing mask for event_type
  Input: remove dev_err() usage after platform_get_irq()
  ...

1 files changed, 47 insertions, 0 deletions

diff --git a/drivers/platform/x86/surfacepro3_button.c b/drivers/platform/x86/surfacepro3_button.c
index 47c6d000465a..ec515223f654 100644
--- a/drivers/platform/x86/surfacepro3_button.c
+++ b/drivers/platform/x86/surfacepro3_button.c
@@ -20,6 +20,12 @@
 #define SURFACE_BUTTON_OBJ_NAME		"VGBI"
 #define SURFACE_BUTTON_DEVICE_NAME	"Surface Pro 3/4 Buttons"
 
+#define MSHW0040_DSM_REVISION		0x01
+#define MSHW0040_DSM_GET_OMPR		0x02	// get OEM Platform Revision
+static const guid_t MSHW0040_DSM_UUID =
+	GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
+		  0x49, 0x80, 0x35);
+
 #define SURFACE_BUTTON_NOTIFY_TABLET_MODE	0xc8
 
 #define SURFACE_BUTTON_NOTIFY_PRESS_POWER	0xc6
@@ -142,6 +148,44 @@ static int surface_button_resume(struct device *dev)
 }
 #endif
 
+/*
+ * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
+ * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
+ * device by checking for the _DSM method and OEM Platform Revision.
+ *
+ * Returns true if the driver should bind to this device, i.e. the device is
+ * either MSWH0028 (Pro 3) or MSHW0040 on a Pro 4 or Book 1.
+ */
+static bool surface_button_check_MSHW0040(struct acpi_device *dev)
+{
+	acpi_handle handle = dev->handle;
+	union acpi_object *result;
+	u64 oem_platform_rev = 0;	// valid revisions are nonzero
+
+	// get OEM platform revision
+	result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
+					 MSHW0040_DSM_REVISION,
+					 MSHW0040_DSM_GET_OMPR,
+					 NULL, ACPI_TYPE_INTEGER);
+
+	/*
+	 * If evaluating the _DSM fails, the method is not present. This means
+	 * that we have either MSHW0028 or MSHW0040 on Pro 4 or Book 1, so we
+	 * should use this driver. We use revision 0 indicating it is
+	 * unavailable.
+	 */
+
+	if (result) {
+		oem_platform_rev = result->integer.value;
+		ACPI_FREE(result);
+	}
+
+	dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
+
+	return oem_platform_rev == 0;
+}
+
+
 static int surface_button_add(struct acpi_device *device)
 {
 	struct surface_button *button;
@@ -154,6 +198,9 @@ static int surface_button_add(struct acpi_device *device)
 	    strlen(SURFACE_BUTTON_OBJ_NAME)))
 		return -ENODEV;
 
+	if (!surface_button_check_MSHW0040(device))
+		return -ENODEV;
+
 	button = kzalloc(sizeof(struct surface_button), GFP_KERNEL);
 	if (!button)
 		return -ENOMEM;