platform/x86: system76: 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 system76 driver.

Fixes: 80b8f68b94ab ("platform/x86: system76: 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/2072699.usQuhbGJ8B@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/system76_acpi.c b/drivers/platform/x86/system76_acpi.c
index 693cbb4613822b6a63d9124cec753958c47d4b8a..dd7b1b07c3165939d182f9c2401c2d4055f118d0 100644 (file)
--- a/drivers/platform/x86/system76_acpi.c
+++ b/drivers/platform/x86/system76_acpi.c
@@ -674,10 +674,14 @@ static void system76_notify(acpi_handle handle, u32 event, void *context)
 // Probe a System76 platform device
 static int system76_probe(struct platform_device *pdev)
 {
-       struct acpi_device *acpi_dev = ACPI_COMPANION(&pdev->dev);
+       struct acpi_device *acpi_dev;
        struct system76_data *data;
        int err;
 
+       acpi_dev = ACPI_COMPANION(&pdev->dev);
+       if (!acpi_dev)
+               return -ENODEV;
+
        data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
        if (!data)
                return -ENOMEM;