From 9feb0763e4985ccfae632de3bb2f029cc8389842 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Mon, 19 Oct 2020 20:56:25 +0200
Subject: [PATCH] platform/x86: acer-wmi: Cleanup accelerometer device handling
Git-commit: 9feb0763e4985ccfae632de3bb2f029cc8389842
Patch-mainline: v5.11-rc1
References: git-fixes

Cleanup accelerometer device handling:
-Drop acer_wmi_accel_destroy instead directly call input_unregister_device.
-The information tracked by the CAP_ACCEL flag mirrors acer_wmi_accel_dev
 being NULL. Drop the CAP flag, this is a preparation change for allowing
 users to override the capability flags. Dropping the flag stops users
 from causing a NULL pointer dereference by forcing the capability.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20201019185628.264473-3-hdegoede@redhat.com
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/platform/x86/acer-wmi.c |   20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -211,7 +211,6 @@ struct hotkey_function_type_aa {
 #define ACER_CAP_BLUETOOTH		BIT(2)
 #define ACER_CAP_BRIGHTNESS		BIT(3)
 #define ACER_CAP_THREEG			BIT(4)
-#define ACER_CAP_ACCEL			BIT(5)
 
 /*
  * Interface type flags
@@ -1516,7 +1515,7 @@ static int acer_gsensor_event(void)
 	struct acpi_buffer output;
 	union acpi_object out_obj[5];
 
-	if (!has_cap(ACER_CAP_ACCEL))
+	if (!acer_wmi_accel_dev)
 		return -1;
 
 	output.length = sizeof(out_obj);
@@ -1925,8 +1924,6 @@ static int __init acer_wmi_accel_setup(v
 	if (err)
 		return err;
 
-	interface->capability |= ACER_CAP_ACCEL;
-
 	acer_wmi_accel_dev = input_allocate_device();
 	if (!acer_wmi_accel_dev)
 		return -ENOMEM;
@@ -1952,11 +1949,6 @@ err_free_dev:
 	return err;
 }
 
-static void acer_wmi_accel_destroy(void)
-{
-	input_unregister_device(acer_wmi_accel_dev);
-}
-
 static int __init acer_wmi_input_setup(void)
 {
 	acpi_status status;
@@ -2111,7 +2103,7 @@ static int acer_resume(struct device *de
 	if (has_cap(ACER_CAP_BRIGHTNESS))
 		set_u32(data->brightness, ACER_CAP_BRIGHTNESS);
 
-	if (has_cap(ACER_CAP_ACCEL))
+	if (acer_wmi_accel_dev)
 		acer_gsensor_init();
 
 	return 0;
@@ -2301,8 +2293,8 @@ error_device_alloc:
 error_platform_register:
 	if (wmi_has_guid(ACERWMID_EVENT_GUID))
 		acer_wmi_input_destroy();
-	if (has_cap(ACER_CAP_ACCEL))
-		acer_wmi_accel_destroy();
+	if (acer_wmi_accel_dev)
+		input_unregister_device(acer_wmi_accel_dev);
 
 	return err;
 }
@@ -2312,8 +2304,8 @@ static void __exit acer_wmi_exit(void)
 	if (wmi_has_guid(ACERWMID_EVENT_GUID))
 		acer_wmi_input_destroy();
 
-	if (has_cap(ACER_CAP_ACCEL))
-		acer_wmi_accel_destroy();
+	if (acer_wmi_accel_dev)
+		input_unregister_device(acer_wmi_accel_dev);
 
 	remove_debugfs();
 	platform_device_unregister(acer_platform_device);