[PATCH v2 3/4] dm: core: add ofnode_get_alias_seq()

[Mehmet Fide <mehmet.fide@gmail.com>]

From: Mehmet Fide <mehmet.fide@screeningeagle.com>

The sequence number an aliases entry gives a node can only be looked up
for a device, through dev_read_alias_seq(). A driver that has to know
the number of a node it does not own, one it reached through a phandle
for instance, has no livetree call for it and is left with fdtdec.

Move the body of dev_read_alias_seq() to the ofnode level and let both
of its variants call it. No functional change, so the moved lines keep
the ENOTSUPP return, the #if and the fdtdec call they had, which is what
checkpatch complains about here.

Signed-off-by: Mehmet Fide <mehmet.fide@screeningeagle.com>
---
 drivers/core/ofnode.c | 20 ++++++++++++++++++++
 drivers/core/read.c   | 20 ++------------------
 include/dm/ofnode.h   | 14 ++++++++++++++
 include/dm/read.h     |  8 ++------
 4 files changed, 38 insertions(+), 24 deletions(-)

diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c
index b5d13c43db1..81d91ce5476 100644
--- a/drivers/core/ofnode.c
+++ b/drivers/core/ofnode.c
@@ -1233,6 +1233,26 @@ ofnode ofnode_get_aliases_node(const char *name)
 	return ofnode_path(prop);
 }
 
+int ofnode_get_alias_seq(ofnode node, const char *stem, int *seqp)
+{
+	int ret = -ENOTSUPP;
+
+	if (ofnode_is_np(node)) {
+		ret = of_alias_get_id(ofnode_to_np(node), stem);
+		if (ret >= 0) {
+			*seqp = ret;
+			ret = 0;
+		}
+	} else {
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+		ret = fdtdec_get_alias_seq(ofnode_to_fdt(node), stem,
+					   ofnode_to_offset(node), seqp);
+#endif
+	}
+
+	return ret;
+}
+
 int ofnode_get_child_count(ofnode parent)
 {
 	ofnode child;
diff --git a/drivers/core/read.c b/drivers/core/read.c
index ba48862f44b..985f6128d97 100644
--- a/drivers/core/read.c
+++ b/drivers/core/read.c
@@ -356,24 +356,8 @@ const void *dev_read_prop_by_prop(struct ofprop *prop,
 
 int dev_read_alias_seq(const struct udevice *dev, int *devnump)
 {
-	ofnode node = dev_ofnode(dev);
-	const char *uc_name = dev->uclass->uc_drv->name;
-	int ret = -ENOTSUPP;
-
-	if (ofnode_is_np(node)) {
-		ret = of_alias_get_id(ofnode_to_np(node), uc_name);
-		if (ret >= 0) {
-			*devnump = ret;
-			ret = 0;
-		}
-	} else {
-#if CONFIG_IS_ENABLED(OF_CONTROL)
-		ret = fdtdec_get_alias_seq(gd->fdt_blob, uc_name,
-					   ofnode_to_offset(node), devnump);
-#endif
-	}
-
-	return ret;
+	return ofnode_get_alias_seq(dev_ofnode(dev),
+				    dev->uclass->uc_drv->name, devnump);
 }
 
 int dev_read_u32_array(const struct udevice *dev, const char *propname,
diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h
index c905e86b283..2363ca0ed33 100644
--- a/include/dm/ofnode.h
+++ b/include/dm/ofnode.h
@@ -1180,6 +1180,20 @@ const void *ofnode_read_aliases_prop(const char *propname, int *sizep);
  */
 ofnode ofnode_get_aliases_node(const char *propname);
 
+/**
+ * ofnode_get_alias_seq() - get the sequence number of a node from its alias
+ *
+ * The aliases node can name a node with a stem and a number, such as
+ * "serial2". This looks the node up and returns the number.
+ *
+ * @node: Node to look for
+ * @stem: Alias stem, e.g. "serial"
+ * @seqp: Returns the sequence number of the alias, if found
+ * Return: 0 if found, -ENOENT if the node has no such alias, -ENOTSUPP if
+ * there is no device tree to look in
+ */
+int ofnode_get_alias_seq(ofnode node, const char *stem, int *seqp);
+
 struct display_timing;
 /**
  * ofnode_decode_display_timing() - decode display timings
diff --git a/include/dm/read.h b/include/dm/read.h
index 12dcde6645c..d0c17c3d343 100644
--- a/include/dm/read.h
+++ b/include/dm/read.h
@@ -1168,12 +1168,8 @@ static inline const void *dev_read_prop_by_prop(struct ofprop *prop,
 
 static inline int dev_read_alias_seq(const struct udevice *dev, int *devnump)
 {
-#if CONFIG_IS_ENABLED(OF_CONTROL)
-	return fdtdec_get_alias_seq(gd->fdt_blob, dev->uclass->uc_drv->name,
-				    dev_of_offset(dev), devnump);
-#else
-	return -ENOTSUPP;
-#endif
+	return ofnode_get_alias_seq(dev_ofnode(dev),
+				    dev->uclass->uc_drv->name, devnump);
 }
 
 static inline int dev_read_u32_array(const struct udevice *dev,
-- 
2.54.0