Commit eb9299beadbd ("ACPI: EC: Use a spin lock without disabing
interrupts") introduced an unexpected user-visible change in
behavior, which is a significant CPU load increase when the EC
is in use.

This most likely happens due to increased spinlock contention
and so reducing this effect would require a major rework of the
EC driver locking.  There is no time for this in the current
cycle, so revert commit eb9299beadbd.

Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218511
Reported-by: Dieter Mummenschanz <dmummenschanz@web.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Since all of the ACPI EC driver code runs in thread context after recent
changes, it does not need to disable interrupts on the local CPU when
acquiring a spin lock.

Make it use the spin lock without disabling interrupts.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

After commit 7a36b901a6eb ("ACPI: OSL: Use a threaded interrupt handler
for SCI") all of the EC code runs in thread context on all systems where
EC events are signaled through a GPE.

It may as well run in thread context on systems using a dedicated IRQ
for EC events signaling, so make it use a threaded handler for that IRQ.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Add GPE quirk entry for HP 250 G7 Notebook PC.

This change allows the lid switch to be identified as the lid switch
and not a keyboard button. With the lid switch properly identified, the
device triggers suspend correctly on lid close.

Signed-off-by: Jonathan Denose <jdenose@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Added GPE quirk entry for the HP Pavilion Gaming 15-dk1xxx.
There is a quirk entry for 2 15-c..... laptops, this is
for a new version which has 15-dk1xxx as identifier.

This fixes the LID switch and rfkill and brightness hotkeys
not working.

Closes: https://github.com/systemd/systemd/issues/28942
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 896e97bf99ec ("ACPI: EC: Clear GPE on interrupt handling only")
broke suspend-to-idle at least on Dell XPS13 9360 and 9380.

The problem is that acpi_ec_dispatch_gpe() must clear the EC GPE,
because the EC GPE handler never runs when the system is in the
suspend-to-idle state and if the EC GPE is not cleared by the suspend-
to-idle loop, it is never cleared at all which leads to a GPE storm.
This causes suspend-to-idle to burn energy instead of saving it which
is potentially dangerous (the affected machines heat up rather badly
when that happens).

Addess this by making acpi_ec_dispatch_gpe() clear the EC GPE as it did
before.

Fixes: 896e97bf99ec ("ACPI: EC: Clear GPE on interrupt handling only")
Tested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

On multiple devices I work on, we noticed that
/sys/firmware/acpi/interrupts/sci_not is non-zero and keeps increasing
over time.

It turns out that there is a race condition between servicing a GPE
interrupt and handling task driven transactions.

If a GPE interrupt is received at the same time ec_poll() is running,
the advance_transaction() clears the GPE flag and the interrupt is not
serviced as acpi_ev_detect_gpe() relies on the GPE flag to call the
handler. As a result, `sci_not' is increased.

To address this, move the GPE status check and clearing from
advance_transaction() directly into acpi_ec_handle_interrupt(), so the
EC GPE only gets cleared in the interrupt handling path.

Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

When removing custom query handlers, the handler might still
be used inside the EC query workqueue, causing a kernel oops
if the module holding the callback function was already unloaded.

Fix this by flushing the EC query workqueue when removing
custom query handlers.

Tested on a Acer Travelmate 4002WLMi

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

According to the ACPI spec part 5.6.4.1.2, EC query handlers discovered
thru ACPI should not be removed when a driver removes his custom query
handler. On the Acer Travelmate 4002WLMi for example, such a query
handler is used as a fallback to handle the EC SMBus alert when no driver
is present.
Change acpi_ec_remove_query_handlers() so that only custom query
handlers are removed then remove_all is false. Query handlers discovered
thru ACPI will still get removed when remove_all is true, which happens
on device removal. Also add a simple check to ensure that
acpi_ec_add_query_handler() is always called with either handle or func
being set, since custom query handlers are detected based whether
handlers->func is set or not.

Tested on a Acer Travelmate 4002WLMi.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
[ rjw: Comment adjustment ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Merge additional ACPI EC driver fixes for 6.2-rc1:

 - Fix EC address space handler unregistration (Hans de Goede).

 - Defer the evaluation of _REG for ECDT described ECs till the matching
   EC device in the DSDT gets parsed and acpi_ec_add() gets called for
   it (Hans de Goede).

* acpi-ec:
  ACPI: EC: Fix ECDT probe ordering issues
  ACPI: EC: Fix EC address space handler unregistration