ACPI: Unbundle execution of _REG methods

From: Alexey Starikovskiy <astarikovskiy@suse.de>

It is too early to run _REG method during the initialization of EC space handler from
ECDT. ACPI specification declares that _REG execution should be postponed to after all _INI
methods are evaluted, thus _REG method execution is unbundled from installing of space handlers,
and for EC ECDT init case moved to later stage.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
---

 drivers/acpi/ec.c              |   26 +++++++++++++-----
 drivers/acpi/events/evxfregn.c |   57 ++++++++++++++++++++++++++++++++++++----
 include/acpi/acpixf.h          |    8 ++++++
 3 files changed, 78 insertions(+), 13 deletions(-)

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index caf873c..a7c962b 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -129,7 +129,8 @@ static struct acpi_ec {
 	struct mutex lock;
 	wait_queue_head_t wait;
 	struct list_head list;
-	u8 handlers_installed;
+	u8 handlers_installed:1;
+	u8 reg_executed:1;
 } *boot_ec, *first_ec;
 
 /* --------------------------------------------------------------------------
@@ -895,6 +896,12 @@ static int acpi_ec_start(struct acpi_device *device)
 
 	ret = ec_install_handlers(ec);
 
+	if (!ret && !ec->reg_executed &&
+	    ACPI_FAILURE(acpi_execute_reg_methods(ec->handle,
+			 ACPI_ADR_SPACE_EC)))
+		return -ENODEV;
+	ec->reg_executed = 1;
+
 	/* EC is fully operational, allow queries */
 	clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 	return ret;
@@ -915,13 +922,18 @@ static int acpi_ec_stop(struct acpi_device *device, int type)
 
 int __init acpi_boot_ec_enable(void)
 {
-	if (!boot_ec || boot_ec->handlers_installed)
-		return 0;
-	if (!ec_install_handlers(boot_ec)) {
-		first_ec = boot_ec;
+	if (!boot_ec)
 		return 0;
-	}
-	return -EFAULT;
+	if (!boot_ec->handlers_installed && ec_install_handlers(boot_ec))
+		return -EFAULT;
+
+	if (!boot_ec->reg_executed &&
+	    ACPI_FAILURE(acpi_execute_reg_methods(boot_ec->handle,
+			 ACPI_ADR_SPACE_EC)))
+		return -EFAULT;
+	boot_ec->reg_executed = 1;
+	first_ec = boot_ec;
+	return 0;
 }
 
 int __init acpi_ec_ecdt_probe(void)
diff --git a/drivers/acpi/events/evxfregn.c b/drivers/acpi/events/evxfregn.c
index 7bf09c5..7cc1c78 100644
--- a/drivers/acpi/events/evxfregn.c
+++ b/drivers/acpi/events/evxfregn.c
@@ -65,10 +65,10 @@ ACPI_MODULE_NAME("evxfregn")
  *
  ******************************************************************************/
 acpi_status
-acpi_install_address_space_handler(acpi_handle device,
-				   acpi_adr_space_type space_id,
-				   acpi_adr_space_handler handler,
-				   acpi_adr_space_setup setup, void *context)
+acpi_install_address_space_handler_noreg(acpi_handle device,
+					 acpi_adr_space_type space_id,
+					 acpi_adr_space_handler handler,
+					 acpi_adr_space_setup setup, void *context)
 {
 	struct acpi_namespace_node *node;
 	acpi_status status;
@@ -103,15 +103,60 @@ acpi_install_address_space_handler(acpi_handle device,
 		goto unlock_and_exit;
 	}
 
-	/* Run all _REG methods for this address space */
+      unlock_and_exit:
+	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+	return_ACPI_STATUS(status);
+}
+
+ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler_noreg)
+
+acpi_status acpi_execute_reg_methods(acpi_handle device,
+	acpi_adr_space_type space_id)
+{
+	struct acpi_namespace_node *node;
+	acpi_status status;
+	if (!device) {
+		return AE_BAD_PARAMETER;
+	}
+	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
 
+	/* Convert and validate the device handle */
+
+	node = acpi_ns_map_handle_to_node(device);
+	if (!node) {
+		status = AE_BAD_PARAMETER;
+		goto unlock_and_exit;
+	}
+
+	/* Run all _REG methods for this address space */
 	status = acpi_ev_execute_reg_methods(node, space_id);
 
-      unlock_and_exit:
+ unlock_and_exit:
 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 	return_ACPI_STATUS(status);
 }
 
+ACPI_EXPORT_SYMBOL(acpi_execute_reg_methods)
+
+acpi_status
+acpi_install_address_space_handler(acpi_handle device,
+				   acpi_adr_space_type space_id,
+				   acpi_adr_space_handler handler,
+				   acpi_adr_space_setup setup,void *context)
+{
+	acpi_status status;
+	status = acpi_install_address_space_handler_noreg(device, space_id,
+							  handler, setup,
+							  context);
+	if (ACPI_FAILURE(status))
+		return status;
+	status = acpi_execute_reg_methods(device, space_id);
+	return status;
+}
+
 ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler)
 
 /*******************************************************************************
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index d970f7f..fbb6769 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -211,6 +211,14 @@ acpi_install_address_space_handler(acpi_handle device,
 				   acpi_adr_space_type space_id,
 				   acpi_adr_space_handler handler,
 				   acpi_adr_space_setup setup, void *context);
+acpi_status
+acpi_install_address_space_handler_noreg(acpi_handle device,
+					 acpi_adr_space_type space_id,
+					 acpi_adr_space_handler handler,
+					 acpi_adr_space_setup setup,
+					 void *context);
+acpi_status acpi_execute_reg_methods(acpi_handle device,
+				     acpi_adr_space_type space_id);
 
 acpi_status
 acpi_remove_address_space_handler(acpi_handle device,