ACPI / i2c-hid: replace open-coded _DSM code with helper functions

Use helper functions to simplify _DSM related code in i2c-hid driver.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 5f7e55f..d22668f 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -850,37 +850,23 @@
 		0xF7, 0xF6, 0xDF, 0x3C, 0x67, 0x42, 0x55, 0x45,
 		0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE,
 	};
-	union acpi_object params[4];
-	struct acpi_object_list input;
+	union acpi_object *obj;
 	struct acpi_device *adev;
-	unsigned long long value;
 	acpi_handle handle;
 
 	handle = ACPI_HANDLE(&client->dev);
 	if (!handle || acpi_bus_get_device(handle, &adev))
 		return -ENODEV;
 
-	input.count = ARRAY_SIZE(params);
-	input.pointer = params;
-
-	params[0].type = ACPI_TYPE_BUFFER;
-	params[0].buffer.length = sizeof(i2c_hid_guid);
-	params[0].buffer.pointer = i2c_hid_guid;
-	params[1].type = ACPI_TYPE_INTEGER;
-	params[1].integer.value = 1;
-	params[2].type = ACPI_TYPE_INTEGER;
-	params[2].integer.value = 1; /* HID function */
-	params[3].type = ACPI_TYPE_PACKAGE;
-	params[3].package.count = 0;
-	params[3].package.elements = NULL;
-
-	if (ACPI_FAILURE(acpi_evaluate_integer(handle, "_DSM", &input,
-								&value))) {
+	obj = acpi_evaluate_dsm_typed(handle, i2c_hid_guid, 1, 1, NULL,
+				      ACPI_TYPE_INTEGER);
+	if (!obj) {
 		dev_err(&client->dev, "device _DSM execution failed\n");
 		return -ENODEV;
 	}
 
-	pdata->hid_descriptor_address = value;
+	pdata->hid_descriptor_address = obj->integer.value;
+	ACPI_FREE(obj);
 
 	return 0;
 }