[RFC v3 3/4] ACPI: EC: Fix EC address space handler unregistration

[Hans de Goede <hdegoede@redhat.com>]

When an ECDT table is present the EC address space handler gets registered
on the root node. So to unregister it properly the unregister call also
must be done on the root node.

Store the ACPI handle used for the acpi_install_address_space_handler()
call and use te same handle for the acpi_remove_address_space_handler()
call.

Reported-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/acpi/ec.c       | 4 +++-
 drivers/acpi/internal.h | 1 +
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index c95e535035a0..55c503225396 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1479,6 +1479,7 @@ static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device)
 			return -ENODEV;
 		}
 		set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
+		ec->address_space_handler_holder = ec->handle;
 	}
 
 	if (!device)
@@ -1530,7 +1531,8 @@ static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device)
 static void ec_remove_handlers(struct acpi_ec *ec)
 {
 	if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
-		if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
+		if (ACPI_FAILURE(acpi_remove_address_space_handler(
+					ec->address_space_handler_holder,
 					ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 			pr_err("failed to remove space handler\n");
 		clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 628bf8f18130..dd3bcbefbc06 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -173,6 +173,7 @@ enum acpi_ec_event_state {
 
 struct acpi_ec {
 	acpi_handle handle;
+	acpi_handle address_space_handler_holder;
 	int gpe;
 	int irq;
 	unsigned long command_addr;
-- 
2.37.3