[PATCH 1/4] platform/x86: wmi: Fix error handling in legacy WMI notify handler functions

[Armin Wolf <W_Armin@gmx.de>]

When wmi_install_notify_handler()/wmi_remove_notify_handler() are
unable to enable/disable the WMI device, they unconditionally return
an error to the caller.
When registering legacy WMI notify handlers, this means that the
callback remains registered despite wmi_install_notify_handler()
having returned an error.
When removing legacy WMI notify handlers, this means that the
callback is removed despite wmi_remove_notify_handler() having
returned an error.

Fix this by only warning when the WMI device could not be enabled.
This behaviour matches the bus-based WMI interface.

Tested on a Dell Inspiron 3505 and a Acer Aspire E1-731.

Fixes: 58f6425eb92f ("WMI: Cater for multiple events with same GUID")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
---
 drivers/platform/x86/wmi.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index a7cfcbf92432..3899a5e3fca7 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -592,9 +592,10 @@ acpi_status wmi_install_notify_handler(const char *guid,
 			block->handler_data = data;

 			wmi_status = wmi_method_enable(block, true);
-			if ((wmi_status != AE_OK) ||
-			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
-				status = wmi_status;
+			if (ACPI_FAILURE(wmi_status))
+				dev_warn(&block->dev.dev, "Failed to enable device\n");
+
+			status = AE_OK;
 		}
 	}

@@ -630,10 +631,13 @@ acpi_status wmi_remove_notify_handler(const char *guid)
 				return AE_NULL_ENTRY;

 			wmi_status = wmi_method_enable(block, false);
+			if (ACPI_FAILURE(wmi_status))
+				dev_warn(&block->dev.dev, "Failed to disable device\n");
+
 			block->handler = NULL;
 			block->handler_data = NULL;
-			if (wmi_status != AE_OK || (wmi_status == AE_OK && status == AE_NOT_EXIST))
-				status = wmi_status;
+
+			status = AE_OK;
 		}
 	}

--
2.39.2