[PATCH 5.11 175/210] platform/x86: intel-hid: Fix spurious wakeups caused by tablet-mode events during suspend

Greg Kroah-Hartman
2021-04-12T09:43:34Z

From: Hans de Goede <hdegoede@redhat.com>

[ Upstream commit a3790a8a94fc0234c5d38013b48e74ef221ec84c ]

Some devices send (duplicate) tablet-mode events when moved around even
though the mode has not changed; and they do this even when suspended.

Change the tablet-mode event handling when priv->wakeup_mode is set to
update the switch state in case it changed and then return immediately
(without calling pm_wakeup_hard_event()) to avoid spurious wakeups.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=212537
Fixes: 537b0dd4729e ("platform/x86: intel-hid: Add support for SW_TABLET_MODE")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Elia Devito <eliadevito@gmail.com>
Link: https://lore.kernel.org/r/20210404143831.25173-1-hdegoede@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/platform/x86/intel-hid.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/x86/intel-hid.c b/drivers/platform/x86/intel-hid.c
index 57cc92891a57..078648a9201b 100644
--- a/drivers/platform/x86/intel-hid.c
+++ b/drivers/platform/x86/intel-hid.c
@@ -483,11 +483,16 @@ static void notify_handler(acpi_handle handle, u32 event, void *context)
goto wakeup;

/*
- * Switch events will wake the device and report the new switch
- * position to the input subsystem.
+ * Some devices send (duplicate) tablet-mode events when moved
+ * around even though the mode has not changed; and they do this
+ * even when suspended.
+ * Update the switch state in case it changed and then return
+ * without waking up to avoid spurious wakeups.
*/
- if (priv->switches && (event == 0xcc || event == 0xcd))
- goto wakeup;
+ if (event == 0xcc || event == 0xcd) {
+ report_tablet_mode_event(priv->switches, event);
+ return;
+ }

/* Wake up on 5-button array events only. */
if (event == 0xc0 || !priv->array)
@@ -501,9 +506,6 @@ static void notify_handler(acpi_handle handle, u32 event, void *context)
wakeup:
pm_wakeup_hard_event(&device->dev);

- if (report_tablet_mode_event(priv->switches, event))
- return;
-
return;
}

--
2.30.2