1 files changed, 78 insertions, 0 deletions

diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c
index db915267d6..c28cf6795f 100644
--- a/drivers/core/uclass.c
+++ b/drivers/core/uclass.c
@@ -158,6 +158,35 @@ int uclass_find_device(enum uclass_id id, int index, struct udevice **devp)
 	return -ENODEV;
 }
 
+int uclass_find_device_by_seq(enum uclass_id id, int seq_or_req_seq,
+			      bool find_req_seq, struct udevice **devp)
+{
+	struct uclass *uc;
+	struct udevice *dev;
+	int ret;
+
+	*devp = NULL;
+	debug("%s: %d %d\n", __func__, find_req_seq, seq_or_req_seq);
+	if (seq_or_req_seq == -1)
+		return -ENODEV;
+	ret = uclass_get(id, &uc);
+	if (ret)
+		return ret;
+
+	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
+		debug("   - %d %d\n", dev->req_seq, dev->seq);
+		if ((find_req_seq ? dev->req_seq : dev->seq) ==
+				seq_or_req_seq) {
+			*devp = dev;
+			debug("   - found\n");
+			return 0;
+		}
+	}
+	debug("   - not found\n");
+
+	return -ENODEV;
+}
+
 /**
  * uclass_get_device_tail() - handle the end of a get_device call
  *
@@ -193,6 +222,23 @@ int uclass_get_device(enum uclass_id id, int index, struct udevice **devp)
 	return uclass_get_device_tail(dev, ret, devp);
 }
 
+int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
+{
+	struct udevice *dev;
+	int ret;
+
+	*devp = NULL;
+	ret = uclass_find_device_by_seq(id, seq, false, &dev);
+	if (ret == -ENODEV) {
+		/*
+		 * We didn't find it in probed devices. See if there is one
+		 * that will request this seq if probed.
+		 */
+		ret = uclass_find_device_by_seq(id, seq, true, &dev);
+	}
+	return uclass_get_device_tail(dev, ret, devp);
+}
+
 int uclass_first_device(enum uclass_id id, struct udevice **devp)
 {
 	struct uclass *uc;
@@ -270,6 +316,37 @@ int uclass_unbind_device(struct udevice *dev)
 	return 0;
 }
 
+int uclass_resolve_seq(struct udevice *dev)
+{
+	struct udevice *dup;
+	int seq;
+	int ret;
+
+	assert(dev->seq == -1);
+	ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, dev->req_seq,
+					false, &dup);
+	if (!ret) {
+		dm_warn("Device '%s': seq %d is in use by '%s'\n",
+			dev->name, dev->req_seq, dup->name);
+	} else if (ret == -ENODEV) {
+		/* Our requested sequence number is available */
+		if (dev->req_seq != -1)
+			return dev->req_seq;
+	} else {
+		return ret;
+	}
+
+	for (seq = 0; seq < DM_MAX_SEQ; seq++) {
+		ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, seq,
+						false, &dup);
+		if (ret == -ENODEV)
+			break;
+		if (ret)
+			return ret;
+	}
+	return seq;
+}
+
 int uclass_post_probe_device(struct udevice *dev)
 {
 	struct uclass_driver *uc_drv = dev->uclass->uc_drv;
@@ -297,6 +374,7 @@ int uclass_pre_remove_device(struct udevice *dev)
 		free(dev->uclass_priv);
 		dev->uclass_priv = NULL;
 	}
+	dev->seq = -1;
 
 	return 0;
 }