[U-Boot] [PATCH] libfdt: Add function to explicitly expand aliases

[U-Boot] [PATCH] libfdt: Add function to explicitly expand aliases

[Jerry Van Baren]

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 <david@gibson.dropbear.id.au>
---

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(-)

diff --git a/include/libfdt.h b/include/libfdt.h
index 5492a53..7cad68c 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -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
diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c
index f559eed..b705f91 100644
--- a/libfdt/fdt_ro.c
+++ b/libfdt/fdt_ro.c
@@ -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;
-- 
1.5.6.5

[U-Boot] [PATCH] libfdt: Add function to explicitly expand aliases

[Petri Lehtinen]

On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
[snip]
> diff --git a/include/libfdt.h b/include/libfdt.h
> index 5492a53..7cad68c 100644
> --- a/include/libfdt.h
> +++ b/include/libfdt.h
> @@ -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);
> +

This should be fdt_get_alias_namelen, right?

Petri

[U-Boot] [PATCH] libfdt: Add function to explicitly expand aliases

[Jon Loeliger]

Petri Lehtinen wrote:
> On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
> [snip]
>> diff --git a/include/libfdt.h b/include/libfdt.h
>> index 5492a53..7cad68c 100644
>> --- a/include/libfdt.h
>> +++ b/include/libfdt.h
>> @@ -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);
>> +
> 
> 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

[U-Boot] [PATCH] libfdt: Add function to explicitly expand aliases

[David Gibson]

On Fri, Oct 03, 2008 at 03:09:06PM -0500, Jon Loeliger wrote:
> Petri Lehtinen wrote:
>> On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
>> [snip]
>>> diff --git a/include/libfdt.h b/include/libfdt.h
>>> index 5492a53..7cad68c 100644
>>> --- a/include/libfdt.h
>>> +++ b/include/libfdt.h
>>> @@ -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);
>>> +
>>
>> 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.

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

-- 
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

[U-Boot] [PATCH] libfdt: Add function to explicitly expand aliases

[David Gibson]

On Fri, Oct 03, 2008 at 03:09:06PM -0500, Jon Loeliger wrote:
> Petri Lehtinen wrote:
>> On Thu, Oct 02, 2008 at 07:05:53PM -0400, Jerry Van Baren wrote:
>> [snip]
>>> diff --git a/include/libfdt.h b/include/libfdt.h
>>> index 5492a53..7cad68c 100644
>>> --- a/include/libfdt.h
>>> +++ b/include/libfdt.h
>>> @@ -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);
>>> +
>>
>> 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.

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 <david@gibson.dropbear.id.au>

Index: dtc/libfdt/libfdt.h
===================================================================
--- dtc.orig/libfdt/libfdt.h	2008-10-04 14:46:50.000000000 +1000
+++ dtc/libfdt/libfdt.h	2008-10-04 14:46:56.000000000 +1000
@@ -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



-- 
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