1 files changed, 28 insertions, 6 deletions

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 79915d4a0031..28c75242fca9 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -825,19 +825,42 @@ bool acpi_check_dsm(acpi_handle handle, const guid_t *guid, u64 rev, u64 funcs)
 EXPORT_SYMBOL(acpi_check_dsm);
 
 /**
+ * acpi_dev_uid_match - Match device by supplied UID
+ * @adev: ACPI device to match.
+ * @uid2: Unique ID of the device.
+ *
+ * Matches UID in @adev with given @uid2.
+ *
+ * Returns:
+ *  - %true if matches.
+ *  - %false otherwise.
+ */
+bool acpi_dev_uid_match(struct acpi_device *adev, const char *uid2)
+{
+	const char *uid1 = acpi_device_uid(adev);
+
+	return uid1 && uid2 && !strcmp(uid1, uid2);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_uid_match);
+
+/**
  * acpi_dev_hid_uid_match - Match device by supplied HID and UID
  * @adev: ACPI device to match.
  * @hid2: Hardware ID of the device.
  * @uid2: Unique ID of the device, pass NULL to not check _UID.
  *
- * Matches HID and UID in @adev with given @hid2 and @uid2.
- * Returns true if matches.
+ * Matches HID and UID in @adev with given @hid2 and @uid2. Absence of @uid2
+ * will be treated as a match. If user wants to validate @uid2, it should be
+ * done before calling this function.
+ *
+ * Returns:
+ *  - %true if matches or @uid2 is NULL.
+ *  - %false otherwise.
  */
 bool acpi_dev_hid_uid_match(struct acpi_device *adev,
 			    const char *hid2, const char *uid2)
 {
 	const char *hid1 = acpi_device_hid(adev);
-	const char *uid1 = acpi_device_uid(adev);
 
 	if (strcmp(hid1, hid2))
 		return false;
@@ -845,7 +868,7 @@ bool acpi_dev_hid_uid_match(struct acpi_device *adev,
 	if (!uid2)
 		return true;
 
-	return uid1 && !strcmp(uid1, uid2);
+	return acpi_dev_uid_match(adev, uid2);
 }
 EXPORT_SYMBOL(acpi_dev_hid_uid_match);
 
@@ -919,8 +942,7 @@ static int acpi_dev_match_cb(struct device *dev, const void *data)
 	if (acpi_match_device_ids(adev, match->hid))
 		return 0;
 
-	if (match->uid && (!adev->pnp.unique_id ||
-	    strcmp(adev->pnp.unique_id, match->uid)))
+	if (match->uid && !acpi_dev_uid_match(adev, match->uid))
 		return 0;
 
 	if (match->hrv == -1)