1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 57570ac47803..e6ce262b5d44 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -39,20 +39,26 @@ static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
                            int size)
 {
         int len;
+        int count;
 
-        if (!acpi_dev->flags.hardware_id)
+        if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
                 return -ENODEV;
 
-        len = snprintf(modalias, size, "acpi:%s:",
-                       acpi_dev->pnp.hardware_id);
-        if (len < 0 || len >= size)
-                return -EINVAL;
+        len = snprintf(modalias, size, "acpi:");
         size -= len;
 
+        if (acpi_dev->flags.hardware_id) {
+                count = snprintf(&modalias[len], size, "%s:",
+                                 acpi_dev->pnp.hardware_id);
+                if (count < 0 || count >= size)
+                        return -EINVAL;
+                len += count;
+                size -= count;
+        }
+
         if (acpi_dev->flags.compatible_ids) {
                 struct acpi_compatible_id_list *cid_list;
                 int i;
-                int count;
 
                 cid_list = acpi_dev->pnp.cid_list;
                 for (i = 0; i < cid_list->count; i++) {