libfdt: Add function to explicitly expand aliases

PATCH New Jerry Van Baren 4 participants 5 messages Oct 2, 2008 – Oct 4, 2008

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Jerry Van Baren

author

2008-10-02 23:05 UTC #0 lore raw

PATCH 1/1 libfdt: Add function to explicitly expand aliases

Kumar has already added alias expansion to fdt_path_offset(). However, in some circumstances it may be convenient for the user of libfdt to explicitly get the string expansion of an alias. This patch adds a function to do this, fdt_get_alias(), and uses it to implement fdt_path_offset().

Signed-off-by David Gibson <[email protected]>

---

Another patch hot off the dtc/libfdt repository.

gvb

 include/libfdt.h |   26 ++++++++++++++++++++++++++
 libfdt/fdt_ro.c  |   26 +++++++++++++++++++-------
 2 files changed, 45 insertions(+), 7 deletions(-)

include/libfdt.h +26 -0

index 5492a53..7cad68c 100644
@@ -459,6 +459,32 @@ static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 
 /**
+ * fdt_get_namelen - get alias based on substring
+ * @fdt: pointer to the device tree blob
+ * @name: name of the alias th look up
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_get_alias(), but only examine the first namelen
+ * characters of name for matching the alias name.
+ */
+const char *fdt_get_alias_namelen(const void *fdt,
+				  const char *name, int namelen);
+
+/**
+ * fdt_get_alias - retreive the path referenced by a given alias
+ * @fdt: pointer to the device tree blob
+ * @name: name of the alias th look up
+ *
+ * fdt_get_alias() retrieves the value of a given alias.  That is, the
+ * value of the property named 'name' in the node /aliases.
+ *
+ * returns:
+ *	a pointer to the expansion of the alias named 'name', of it exists
+ *	NULL, if the given alias or the /aliases node does not exist
+ */
+const char *fdt_get_alias(const void *fdt, const char *name);
+
+/**
  * fdt_get_path - determine the full path of a node
  * @fdt: pointer to the device tree blob
  * @nodeoffset: offset of the node whose path to find

libfdt/fdt_ro.c +19 -7

index f559eed..b705f91 100644
@@ -145,17 +145,12 @@ int fdt_path_offset(const void *fdt, const char *path)
 
 	/* see if we have an alias */
 	if (*path != '/') {
-		const char *q;
-		int aliasoffset = fdt_path_offset(fdt, "/aliases");
-
-		if (aliasoffset < 0)
-			return -FDT_ERR_BADPATH;
+		const char *q = strchr(path, '/');
 
-		q = strchr(path, '/');
 		if (!q)
 			q = end;
 
-		p = fdt_getprop_namelen(fdt, aliasoffset, path, q - p, NULL);
+		p = fdt_get_alias_namelen(fdt, p, q - p);
 		if (!p)
 			return -FDT_ERR_BADPATH;
 		offset = fdt_path_offset(fdt, p);

@@ -306,6 +301,23 @@ uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
 	return fdt32_to_cpu(*php);
 }
 
+const char *fdt_get_alias_namelen(const void *fdt,
+				  const char *name, int namelen)
+{
+	int aliasoffset;
+
+	aliasoffset = fdt_path_offset(fdt, "/aliases");
+	if (aliasoffset < 0)
+		return NULL;
+
+	return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
+}
+
+const char *fdt_get_alias(const void *fdt, const char *name)
+{
+	return fdt_get_alias_namelen(fdt, name, strlen(name));
+}
+
 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
 {
 	int pdepth = 0, p = 0;

Signature · 1 line

1.5.6.5

Petri Lehtinen

2008-10-03 20:00 UTC #1 lore raw

PATCH 1/1 libfdt: Add function to explicitly expand aliases

On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
[snip]

include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 462

Quoted 9 lines

include/libfdt.h +1 -0

index 5492a53..7cad68c 100644
@@ -459,6 +459,32 @@ static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 
 /**
+ * fdt_get_namelen - get alias based on substring

===^^^^^^^^^^^^^^^===

include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 472

Quoted 10 lines

include/libfdt.h +10 -0

+ * @fdt: pointer to the device tree blob
+ * @name: name of the alias th look up
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_get_alias(), but only examine the first namelen
+ * characters of name for matching the alias name.
+ */
+const char *fdt_get_alias_namelen(const void *fdt,
+				  const char *name, int namelen);
+

This should be fdt_get_alias_namelen, right?

Petri

Jon Loeliger

2008-10-03 20:09 UTC #2 lore raw

PATCH 1/1 libfdt: Add function to explicitly expand aliases

Quoted 12 lines · Petri Lehtinen

On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
[snip]
include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 462
Quoted 9 lines
include/libfdt.h +1 -0
index 5492a53..7cad68c 100644
@@ -459,6 +459,32 @@ static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 
 /**
+ * fdt_get_namelen - get alias based on substring
===^^^^^^^^^^^^^^^===

Quoted 13 lines

include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 472

Quoted 10 lines

include/libfdt.h +10 -0

+ * @fdt: pointer to the device tree blob
+ * @name: name of the alias th look up
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_get_alias(), but only examine the first namelen
+ * characters of name for matching the alias name.
+ */
+const char *fdt_get_alias_namelen(const void *fdt,
+				  const char *name, int namelen);
+

This should be fdt_get_alias_namelen, right?

It does look that way....

This patch has already been applied upstream,
so correcting patches on top of this are welcome.

Thanks,
jdl

David Gibson

2008-10-04 02:42 UTC #3 lore raw

PATCH 1/1 libfdt: Add function to explicitly expand aliases

Quoted 26 lines · Jon Loeliger

Quoted 11 lines · Petri Lehtinen
On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
[snip]
include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 461
Quoted 8 lines
include/libfdt.h +1 -0
index 5492a53..7cad68c 100644
@@ -459,6 +459,32 @@ static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
  /**
+ * fdt_get_namelen - get alias based on substring
===^^^^^^^^^^^^^^^===
Quoted 13 lines
include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 472
Quoted 10 lines
include/libfdt.h +10 -0
+ * @fdt: pointer to the device tree blob
+ * @name: name of the alias th look up
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_get_alias(), but only examine the first namelen
+ * characters of name for matching the alias name.
+ */
+const char *fdt_get_alias_namelen(const void *fdt,
+				  const char *name, int namelen);
+
This should be fdt_get_alias_namelen, right?

Quoted 4 lines

It does look that way....
This patch has already been applied upstream,
so correcting patches on top of this are welcome.

Crap, sorry. I'll send a fixup patch if none of you gets to it first.

Signature · 4 lines

David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

David Gibson

2008-10-04 04:49 UTC #4 lore raw

PATCH 1/1 libfdt: Add function to explicitly expand aliases

In reply to Jon Loeliger

Quoted 25 lines · Jon Loeliger

Quoted 11 lines · Petri Lehtinen
On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
[snip]
include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 461
Quoted 8 lines
include/libfdt.h +1 -0
index 5492a53..7cad68c 100644
@@ -459,6 +459,32 @@ static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
  /**
+ * fdt_get_namelen - get alias based on substring
===^^^^^^^^^^^^^^^===
Quoted 12 lines
include/libfdt.h static inline void *fdt_getprop_w(void *fdt, int nodeoffset, · line 471
Quoted 10 lines
include/libfdt.h +10 -0
+ * @fdt: pointer to the device tree blob
+ * @name: name of the alias th look up
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_get_alias(), but only examine the first namelen
+ * characters of name for matching the alias name.
+ */
+const char *fdt_get_alias_namelen(const void *fdt,
+				  const char *name, int namelen);
+
This should be fdt_get_alias_namelen, right?

Quoted 4 lines

It does look that way....
This patch has already been applied upstream,
so correcting patches on top of this are welcome.

libfdt: Fix error in documentation for fdt_get_alias_namelen()

Oops, screwed up the function name in the documenting comment for this function. Trivial correction in this patch.

Signed-off-by David Gibson <[email protected]>

libfdt/libfdt.h +1 -1

Index: dtc/libfdt/libfdt.h
===================================================================
@@ -459,7 +459,7 @@ static inline void *fdt_getprop_w(void *
 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 
 /**
- * fdt_get_namelen - get alias based on substring
+ * fdt_get_alias_namelen - get alias based on substring
  * @fdt: pointer to the device tree blob
  * @name: name of the alias th look up
  * @namelen: number of characters of name to consider

Signature · 4 lines

David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson