1 files changed, 47 insertions, 8 deletions

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 0df9b4461766..994a90747420 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -235,6 +235,19 @@ static int __init deferred_probe_timeout_setup(char *str)
 }
 __setup("deferred_probe_timeout=", deferred_probe_timeout_setup);
 
+static int __driver_deferred_probe_check_state(struct device *dev)
+{
+        if (!initcalls_done)
+                return -EPROBE_DEFER;
+
+        if (!deferred_probe_timeout) {
+                dev_WARN(dev, "deferred probe timeout, ignoring dependency");
+                return -ETIMEDOUT;
+        }
+
+        return 0;
+}
+
 /**
  * driver_deferred_probe_check_state() - Check deferred probe state
  * @dev: device to check
@@ -248,14 +261,40 @@ __setup("deferred_probe_timeout=", deferred_probe_timeout_setup);
  */
 int driver_deferred_probe_check_state(struct device *dev)
 {
-        if (initcalls_done) {
-                if (!deferred_probe_timeout) {
-                        dev_WARN(dev, "deferred probe timeout, ignoring dependency");
-                        return -ETIMEDOUT;
-                }
-                dev_warn(dev, "ignoring dependency for device, assuming no driver");
-                return -ENODEV;
-        }
+        int ret;
+
+        ret = __driver_deferred_probe_check_state(dev);
+        if (ret < 0)
+                return ret;
+
+        dev_warn(dev, "ignoring dependency for device, assuming no driver");
+
+        return -ENODEV;
+}
+
+/**
+ * driver_deferred_probe_check_state_continue() - check deferred probe state
+ * @dev: device to check
+ *
+ * Returns -ETIMEDOUT if deferred probe debug timeout has expired, or
+ * -EPROBE_DEFER otherwise.
+ *
+ * Drivers or subsystems can opt-in to calling this function instead of
+ * directly returning -EPROBE_DEFER.
+ *
+ * This is similar to driver_deferred_probe_check_state(), but it allows the
+ * subsystem to keep deferring probe after built-in drivers have had a chance
+ * to probe. One scenario where that is useful is if built-in drivers rely on
+ * resources that are provided by modular drivers.
+ */
+int driver_deferred_probe_check_state_continue(struct device *dev)
+{
+        int ret;
+
+        ret = __driver_deferred_probe_check_state(dev);
+        if (ret < 0)
+                return ret;
+
         return -EPROBE_DEFER;
 }