platform/x86: acer-wmi: Cleanup accelerometer device handling

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

diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c
index 1683fd3..60d2c38 100644 (file)
--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -210,7 +210,6 @@ 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
@@ -1509,7 +1508,7 @@ 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);
@@ -1883,8 +1882,6 @@ static int __init acer_wmi_accel_setup(void)
        gsensor_handle = acpi_device_handle(adev);
        acpi_dev_put(adev);
 
-       interface->capability |= ACER_CAP_ACCEL;
-
        acer_wmi_accel_dev = input_allocate_device();
        if (!acer_wmi_accel_dev)
                return -ENOMEM;
@@ -1910,11 +1907,6 @@ 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;
@@ -2069,7 +2061,7 @@ static int acer_resume(struct device *dev)
        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;
@@ -2259,8 +2251,8 @@ 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;
 }
@@ -2270,8 +2262,8 @@ 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);