This is a note to let you know that I've just added the patch titled ACPI / EC: Fix regression related to triggering source of EC event handling ACPI / EC: Fix an issue that SCI_EVT cannot be detected ACPI / EC: Remove old CLEAR_ON_RESUME quirk Revert "ACPI / EC: Enable event freeze mode..." to fix to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: acpi-ec-fix-regression-related-to-triggering-source-of-ec-event-handling.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 53c5eaabaea9a1b7a96f95ccc486d2ad721d95bb Mon Sep 17 00:00:00 2001 From: Lv Zheng <lv.zheng@xxxxxxxxx> Date: Tue, 26 Sep 2017 16:54:03 +0800 Subject: ACPI / EC: Fix regression related to triggering source of EC event handling From: Lv Zheng <lv.zheng@xxxxxxxxx> commit 53c5eaabaea9a1b7a96f95ccc486d2ad721d95bb upstream. Originally the Samsung quirks removed by commit 4c237371 can be covered by commit e923e8e7 and ec_freeze_events=Y mode. But commit 9c40f956 changed ec_freeze_events=Y back to N, making this problem re-surface. Actually, if commit e923e8e7 is robust enough, we can freely change ec_freeze_events mode, so this patch fixes the issue by improving commit e923e8e7. Related commits listed in the merged order: Commit: e923e8e79e18fd6be9162f1be6b99a002e9df2cb Subject: ACPI / EC: Fix an issue that SCI_EVT cannot be detected after event is enabled Commit: 4c237371f290d1ed3b2071dd43554362137b1cce Subject: ACPI / EC: Remove old CLEAR_ON_RESUME quirk Commit: 9c40f956ce9b331493347d1b3cb7e384f7dc0581 Subject: Revert "ACPI / EC: Enable event freeze mode..." to fix a regression This patch not only fixes the reported post-resume EC event triggering source issue, but also fixes an unreported similar issue related to the driver bind by adding EC event triggering source in ec_install_handlers(). Fixes: e923e8e79e18 (ACPI / EC: Fix an issue that SCI_EVT cannot be detected after event is enabled) Fixes: 4c237371f290 (ACPI / EC: Remove old CLEAR_ON_RESUME quirk) Fixes: 9c40f956ce9b (Revert "ACPI / EC: Enable event freeze mode..." to fix a regression) Link: https://bugzilla.kernel.org/show_bug.cgi?id=196833 Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> Reported-by: Alistair Hamilton <ahpatent@xxxxxxxxx> Tested-by: Alistair Hamilton <ahpatent@xxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/ec.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -482,8 +482,11 @@ static inline void __acpi_ec_enable_even { if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) ec_log_drv("event unblocked"); - if (!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) - advance_transaction(ec); + /* + * Unconditionally invoke this once after enabling the event + * handling mechanism to detect the pending events. + */ + advance_transaction(ec); } static inline void __acpi_ec_disable_event(struct acpi_ec *ec) @@ -1458,11 +1461,10 @@ static int ec_install_handlers(struct ac if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) acpi_ec_enable_gpe(ec, true); - - /* EC is fully operational, allow queries */ - acpi_ec_enable_event(ec); } } + /* EC is fully operational, allow queries */ + acpi_ec_enable_event(ec); return 0; } Patches currently in stable-queue which might be from lv.zheng@xxxxxxxxx are queue-4.9/acpi-ec-fix-regression-related-to-triggering-source-of-ec-event-handling.patch