dm: core: Add a new sequence number for devices

At present each device has two sequence numbers, with 'req_seq' being
set up at bind time and 'seq' at probe time. The idea is that devices
can 'request' a sequence number and then the conflicts are resolved when
the device is probed.

This makes things complicated in a few cases, since we don't really know
what the sequence number will end up being. We want to honour the
bind-time requests if at all possible, but in fact the only source of
these at present is the devicetree aliases. Since we have the devicetree
available at bind time, we may as well just use it, in the hope that the
required processing will turn out to be useful later (i.e. the device
actually gets used).

Add a new 'sqq' member, the bind-time sequence number. It operates in
parallel to the old values for now. All devices get a valid sqq value,
i.e. it is never -1.

Drop an #ifdef while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>

2 files changed, 21 insertions, 9 deletions

diff --git a/drivers/core/device.c b/drivers/core/device.c
index 22d80694cd8..8d1287f9a19 100644
--- a/drivers/core/device.c
+++ b/drivers/core/device.c
@@ -41,6 +41,7 @@ static int device_bind_common(struct udevice *parent, const struct driver *drv,
 	struct udevice *dev;
 	struct uclass *uc;
 	int size, ret = 0;
+	bool auto_seq = true;
 
 	if (devp)
 		*devp = NULL;
@@ -73,6 +74,7 @@ static int device_bind_common(struct udevice *parent, const struct driver *drv,
 
 	dev->seq = -1;
 	dev->req_seq = -1;
+	dev->sqq = -1;
 	if (CONFIG_IS_ENABLED(DM_SEQ_ALIAS) &&
 	    (uc->uc_drv->flags & DM_UC_FLAG_SEQ_ALIAS)) {
 		/*
@@ -84,17 +86,25 @@ static int device_bind_common(struct udevice *parent, const struct driver *drv,
 		 */
 		if (CONFIG_IS_ENABLED(OF_CONTROL) &&
 		    !CONFIG_IS_ENABLED(OF_PLATDATA)) {
-			if (uc->uc_drv->name && ofnode_valid(node))
+			if (uc->uc_drv->name && ofnode_valid(node)) {
+				dev_read_alias_seq(dev, &dev->sqq);
 				dev_read_alias_seq(dev, &dev->req_seq);
-#if CONFIG_IS_ENABLED(OF_PRIOR_STAGE)
-			if (dev->req_seq == -1)
-				dev->req_seq =
-					uclass_find_next_free_req_seq(uc);
-#endif
+				auto_seq = false;
+			}
+			if (CONFIG_IS_ENABLED(OF_PRIOR_STAGE)) {
+				if (dev->req_seq == -1) {
+					auto_seq = true;
+					dev->req_seq =
+						uclass_find_next_free_req_seq(
+							uc);
+				}
+			}
 		} else {
 			dev->req_seq = uclass_find_next_free_req_seq(uc);
 		}
 	}
+	if (auto_seq)
+		dev->sqq = uclass_find_next_free_req_seq(uc);
 
 	if (drv->plat_auto) {
 		bool alloc = !plat;
diff --git a/drivers/core/root.c b/drivers/core/root.c
index 672aa7cea72..f2fba5883aa 100644
--- a/drivers/core/root.c
+++ b/drivers/core/root.c
@@ -311,22 +311,24 @@ int dm_init_and_scan(bool pre_reloc_only)
 	ret = dm_scan_plat(pre_reloc_only);
 	if (ret) {
 		debug("dm_scan_plat() failed: %d\n", ret);
-		return ret;
+		goto fail;
 	}
 
 	if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) {
 		ret = dm_extended_scan(pre_reloc_only);
 		if (ret) {
 			debug("dm_extended_scan() failed: %d\n", ret);
-			return ret;
+			goto fail;
 		}
 	}
 
 	ret = dm_scan_other(pre_reloc_only);
 	if (ret)
-		return ret;
+		goto fail;
 
 	return 0;
+fail:
+	return ret;
 }
 
 #ifdef CONFIG_ACPIGEN