platform/x86: asus-wireless: Fix uninitialized symbol usage

'ret' will not be initialized if acpi_evaluate_integer() returns through
an error path, so it should not be used in this case. This fixes the
following Smatch static analyser error:

 drivers/platform/x86/asus-wireless.c:76 asus_wireless_method() error:
                                                     uninitialized symbol 'ret'.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

diff --git a/drivers/platform/x86/asus-wireless.c b/drivers/platform/x86/asus-wireless.c
index 0e9f5ec1347443c10dbb8aad846ae53a3d9464b4..7458f7602d5e73be5fcd9b341a54b8ba0290c3b9 100644 (file)
--- a/drivers/platform/x86/asus-wireless.c
+++ b/drivers/platform/x86/asus-wireless.c
@@ -52,13 +52,12 @@ static const struct acpi_device_id device_ids[] = {
 };
 MODULE_DEVICE_TABLE(acpi, device_ids);
 
-static u64 asus_wireless_method(acpi_handle handle, const char *method,
-                               int param)
+static acpi_status asus_wireless_method(acpi_handle handle, const char *method,
+                                       int param, u64 *ret)
 {
        struct acpi_object_list p;
        union acpi_object obj;
        acpi_status s;
-       u64 ret;
 
        acpi_handle_debug(handle, "Evaluating method %s, parameter %#x\n",
                          method, param);
@@ -67,24 +66,27 @@ static u64 asus_wireless_method(acpi_handle handle, const char *method,
        p.count = 1;
        p.pointer = &obj;
 
-       s = acpi_evaluate_integer(handle, (acpi_string) method, &p, &ret);
+       s = acpi_evaluate_integer(handle, (acpi_string) method, &p, ret);
        if (ACPI_FAILURE(s))
                acpi_handle_err(handle,
                                "Failed to eval method %s, param %#x (%d)\n",
                                method, param, s);
-       acpi_handle_debug(handle, "%s returned %#llx\n", method, ret);
-       return ret;
+       else
+               acpi_handle_debug(handle, "%s returned %#llx\n", method, *ret);
+
+       return s;
 }
 
 static enum led_brightness led_state_get(struct led_classdev *led)
 {
        struct asus_wireless_data *data;
-       int s;
+       acpi_status s;
+       u64 ret;
 
        data = container_of(led, struct asus_wireless_data, led);
        s = asus_wireless_method(acpi_device_handle(data->adev), "HSWC",
-                                data->hswc_params->status);
-       if (s == data->hswc_params->on)
+                                data->hswc_params->status, &ret);
+       if (ACPI_SUCCESS(s) && ret == data->hswc_params->on)
                return LED_FULL;
        return LED_OFF;
 }
@@ -92,10 +94,11 @@ static enum led_brightness led_state_get(struct led_classdev *led)
 static void led_state_update(struct work_struct *work)
 {
        struct asus_wireless_data *data;
+       u64 ret;
 
        data = container_of(work, struct asus_wireless_data, led_work);
        asus_wireless_method(acpi_device_handle(data->adev), "HSWC",
-                            data->led_state);
+                            data->led_state, &ret);
 }
 
 static void led_state_set(struct led_classdev *led, enum led_brightness value)