platform/x86: wireless-hotkey: Check ACPI_COMPANION() against NULL

Every platform driver can be forced to match a device that doesn't match
its list of device IDs because of device_match_driver_override(), so
platform drivers that rely on the existence of a device's ACPI companion
object need to verify its presence.

Accordingly, add a requisite ACPI_COMPANION() check against NULL to the
platform/x86 wireless-hotkey driver.

Fixes: 8507277ef132 ("platform/x86: wireless-hotkey: Convert ACPI driver to a platform one")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/3899916.MHq7AAxBmi@rafael.j.wysocki
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/wireless-hotkey.c b/drivers/platform/x86/wireless-hotkey.c
index f680d8ff8e87757f04507f8b149369de8f0b19ab..3151844d1699ddefbd33daf8c0a7de2ebcc6ebd1 100644 (file)
--- a/drivers/platform/x86/wireless-hotkey.c
+++ b/drivers/platform/x86/wireless-hotkey.c
@@ -89,9 +89,14 @@ static void wl_notify(acpi_handle handle, u32 event, void *data)
 
 static int wl_probe(struct platform_device *pdev)
 {
+       struct acpi_device *adev;
        struct wl_button *button;
        int err;
 
+       adev = ACPI_COMPANION(&pdev->dev);
+       if (!adev)
+               return -ENODEV;
+
        button = kzalloc_obj(struct wl_button);
        if (!button)
                return -ENOMEM;
@@ -104,8 +109,8 @@ static int wl_probe(struct platform_device *pdev)
                kfree(button);
                return err;
        }
-       err = acpi_dev_install_notify_handler(ACPI_COMPANION(&pdev->dev),
-                                             ACPI_DEVICE_NOTIFY, wl_notify, button);
+       err = acpi_dev_install_notify_handler(adev, ACPI_DEVICE_NOTIFY,
+                                             wl_notify, button);
        if (err) {
                pr_err("Failed to install ACPI notify handler\n");
                wireless_input_destroy(&pdev->dev);