[PATCH v2 4/5] platform/x86: intel_sar: Check ACPI_HANDLE() against NULL

["Rafael J. Wysocki" <rafael@kernel.org>]

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

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_HANDLE() check against NULL to the
platform/x86 intel_sar driver.

Fixes: dcfbd31ef4bc ("platform/x86: BIOS SAR driver for Intel M.2 Modem")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/platform/x86/intel/int1092/intel_sar.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/platform/x86/intel/int1092/intel_sar.c
+++ b/drivers/platform/x86/intel/int1092/intel_sar.c
@@ -245,15 +245,20 @@ static void sar_get_data(int reg, struct
 static int sar_probe(struct platform_device *device)
 {
 	struct wwan_sar_context *context;
+	acpi_handle handle;
 	int reg;
 	int result;
 
+	handle = ACPI_HANDLE(&device->dev);
+	if (!handle)
+		return -ENODEV;
+
 	context = kzalloc_obj(*context);
 	if (!context)
 		return -ENOMEM;
 
 	context->sar_device = device;
-	context->handle = ACPI_HANDLE(&device->dev);
+	context->handle = handle;
 	dev_set_drvdata(&device->dev, context);
 
 	result = guid_parse(SAR_DSM_UUID, &context->guid);