* [RFC v3 1/3] of: Add a testcase for of_find_node_by_path()
2014-03-14 17:11 [RFC v3 0/3] Add aliases parsing to of_find_node_by_path() Grant Likely
@ 2014-03-14 17:11 ` Grant Likely
2014-03-14 17:11 ` [RFC v3 2/3] lib: add glibc style strchrnul() variant Grant Likely
` (2 subsequent siblings)
3 siblings, 0 replies; 7+ messages in thread
From: Grant Likely @ 2014-03-14 17:11 UTC (permalink / raw)
To: linux-kernel, devicetree; +Cc: Pantelis Antoniou, Grant Likely
Add a testcase for the find_node_by_path() function to make sure it
handles all the valid scenarios.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
drivers/of/selftest.c | 39 +++++++++++++++++++++++++++++
drivers/of/testcase-data/tests-phandle.dtsi | 6 ++++-
2 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
index ae4450070503..f5b4dcffbe32 100644
--- a/drivers/of/selftest.c
+++ b/drivers/of/selftest.c
@@ -30,6 +30,43 @@ static struct selftest_results {
} \
}
+static void __init of_selftest_find_node_by_name(void)
+{
+ struct device_node *np;
+
+ np = of_find_node_by_path("/testcase-data");
+ selftest(np && !strcmp("/testcase-data", np->full_name),
+ "find /testcase-data failed\n");
+ of_node_put(np);
+
+ np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+ selftest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+ "find /testcase-data/phandle-tests/consumer-a failed\n");
+ of_node_put(np);
+
+ np = of_find_node_by_path("testcase-alias");
+ selftest(np && !strcmp("/testcase-data", np->full_name),
+ "find testcase-alias failed\n");
+ of_node_put(np);
+
+ np = of_find_node_by_path("testcase-alias/phandle-tests/consumer-a");
+ selftest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+ "find testcase-alias/phandle-tests/consumer-a failed\n");
+ of_node_put(np);
+
+ np = of_find_node_by_path("/testcase-data/missing-path");
+ selftest(!np, "non-existent path returned node %s\n", np->full_name);
+ of_node_put(np);
+
+ np = of_find_node_by_path("missing-alias");
+ selftest(!np, "non-existent alias returned node %s\n", np->full_name);
+ of_node_put(np);
+
+ np = of_find_node_by_path("testcase-alias/missing-path");
+ selftest(!np, "non-existent alias with relative path returned node %s\n", np->full_name);
+ of_node_put(np);
+}
+
static void __init of_selftest_dynamic(void)
{
struct device_node *np;
@@ -89,6 +126,7 @@ static void __init of_selftest_dynamic(void)
if (prop->value)
selftest(of_add_property(np, prop) == 0,
"Adding a large property should have passed\n");
+
}
static void __init of_selftest_parse_phandle_with_args(void)
@@ -439,6 +477,7 @@ static int __init of_selftest(void)
of_node_put(np);
pr_info("start of selftest - you will see error messages\n");
+ of_selftest_find_node_by_name();
of_selftest_dynamic();
of_selftest_parse_phandle_with_args();
of_selftest_property_match_string();
diff --git a/drivers/of/testcase-data/tests-phandle.dtsi b/drivers/of/testcase-data/tests-phandle.dtsi
index 788a4c24b8f5..ce0fe083d406 100644
--- a/drivers/of/testcase-data/tests-phandle.dtsi
+++ b/drivers/of/testcase-data/tests-phandle.dtsi
@@ -1,6 +1,10 @@
/ {
- testcase-data {
+ aliases {
+ testcase-alias = &testcase;
+ };
+
+ testcase: testcase-data {
security-password = "password";
duplicate-name = "duplicate";
duplicate-name { };
--
1.8.3.2
^ permalink raw reply related [flat|nested] 7+ messages in thread* [RFC v3 2/3] lib: add glibc style strchrnul() variant
2014-03-14 17:11 [RFC v3 0/3] Add aliases parsing to of_find_node_by_path() Grant Likely
2014-03-14 17:11 ` [RFC v3 1/3] of: Add a testcase for of_find_node_by_path() Grant Likely
@ 2014-03-14 17:11 ` Grant Likely
2014-03-14 17:11 ` [RFC v3 3/3] of: Make of_find_node_by_path() handle /aliases Grant Likely
[not found] ` < 1394817109-26199-4-git-send-email-grant.likely@linaro.org>
3 siblings, 0 replies; 7+ messages in thread
From: Grant Likely @ 2014-03-14 17:11 UTC (permalink / raw)
To: linux-kernel, devicetree; +Cc: Pantelis Antoniou, Grant Likely
The strchrnul() variant helpfully returns a the end of the string
instead of a NULL if the requested character is not found. This can
simplify string parsing code since it doesn't need to expicitly check
for a NULL return. If a valid string pointer is passed in, then a valid
null terminated string will always come back out.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
include/linux/string.h | 3 +++
lib/string.c | 15 +++++++++++++++
2 files changed, 18 insertions(+)
diff --git a/include/linux/string.h b/include/linux/string.h
index ac889c5ea11b..d36977e029af 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -52,6 +52,9 @@ extern int strncasecmp(const char *s1, const char *s2, size_t n);
#ifndef __HAVE_ARCH_STRCHR
extern char * strchr(const char *,int);
#endif
+#ifndef __HAVE_ARCH_STRCHRNUL
+extern char * strchrnul(const char *,int);
+#endif
#ifndef __HAVE_ARCH_STRNCHR
extern char * strnchr(const char *, size_t, int);
#endif
diff --git a/lib/string.c b/lib/string.c
index e5878de4f101..879e839cc555 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -301,6 +301,21 @@ char *strchr(const char *s, int c)
EXPORT_SYMBOL(strchr);
#endif
+#ifndef __HAVE_ARCH_STRCHRNUL
+/**
+ * strchr - Find the first occurrence of a character in a string
+ * @s: The string to be searched
+ * @c: The character to search for
+ */
+char *strchrnul(const char *s, int c)
+{
+ while (*s && *s != (char)c)
+ s++;
+ return (char *)s;
+}
+EXPORT_SYMBOL(strchrnul);
+#endif
+
#ifndef __HAVE_ARCH_STRRCHR
/**
* strrchr - Find the last occurrence of a character in a string
--
1.8.3.2
^ permalink raw reply related [flat|nested] 7+ messages in thread* [RFC v3 3/3] of: Make of_find_node_by_path() handle /aliases
2014-03-14 17:11 [RFC v3 0/3] Add aliases parsing to of_find_node_by_path() Grant Likely
2014-03-14 17:11 ` [RFC v3 1/3] of: Add a testcase for of_find_node_by_path() Grant Likely
2014-03-14 17:11 ` [RFC v3 2/3] lib: add glibc style strchrnul() variant Grant Likely
@ 2014-03-14 17:11 ` Grant Likely
2014-03-14 21:39 ` Rob Herring
[not found] ` < 1394817109-26199-4-git-send-email-grant.likely@linaro.org>
3 siblings, 1 reply; 7+ messages in thread
From: Grant Likely @ 2014-03-14 17:11 UTC (permalink / raw)
To: linux-kernel, devicetree; +Cc: Pantelis Antoniou, Grant Likely, David Daney
Make of_find_node_by_path() handle aliases as prefixes. To make this
work the name search is refactored to search by path component instead
of by full string. This should be a more efficient search, and it makes
it possible to start a search at a subnode of a tree.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Rework to not require allocating at runtime]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
drivers/of/base.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 56 insertions(+), 4 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 7083fad079a6..b8b673526dbd 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -770,9 +770,38 @@ struct device_node *of_get_child_by_name(const struct device_node *node,
}
EXPORT_SYMBOL(of_get_child_by_name);
+static struct device_node *__of_find_node_by_path(struct device_node *parent,
+ const char *path)
+{
+ struct device_node *child;
+ int len = strchrnul(path, '/') - path;
+
+ if (!len)
+ return parent;
+
+ for_each_child_of_node(parent, child) {
+ const char *name = strrchr(child->full_name, '/');
+ if (WARN(!name, "malformed device_node %s\n", child->full_name))
+ continue;
+ name++;
+ if (strncmp(path, name, len) == 0 && (strlen(name) == len))
+ return child;
+ }
+ return NULL;
+}
+
/**
* of_find_node_by_path - Find a node matching a full OF path
* @path: The full path to match
+ * @path: Either the full path to match, or if the path does not
+ * start with '/', the name of a property of the /aliases
+ * node (an alias). In the case of an alias, the node
+ * matching the alias' value will be returned.
+ *
+ * Valid paths:
+ * /foo/bar Full path
+ * foo Valid alias
+ * foo/bar Valid alias + relative path
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
@@ -780,13 +809,36 @@ EXPORT_SYMBOL(of_get_child_by_name);
struct device_node *of_find_node_by_path(const char *path)
{
struct device_node *np = of_allnodes;
+ struct property *pp;
unsigned long flags;
+ /* The path could begin with an alias */
+ if (*path != '/') {
+ char *p = strchrnul(path, '/');
+ int len = p - path;
+
+ /* of_aliases must not be NULL */
+ if (!of_aliases)
+ return NULL;
+
+ np = NULL;
+ for_each_property_of_node(of_aliases, pp) {
+ if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
+ np = of_find_node_by_path(pp->value);
+ break;
+ }
+ }
+ if (!np)
+ return NULL;
+ path = p;
+ }
+
+ /* Step down the tree matching path components */
raw_spin_lock_irqsave(&devtree_lock, flags);
- for (; np; np = np->allnext) {
- if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
- && of_node_get(np))
- break;
+ while (np && *path == '/') {
+ path++; /* Increment past '/' delimiter */
+ np = __of_find_node_by_path(np, path);
+ path = strchrnul(path, '/');
}
raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
--
1.8.3.2
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [RFC v3 3/3] of: Make of_find_node_by_path() handle /aliases
2014-03-14 17:11 ` [RFC v3 3/3] of: Make of_find_node_by_path() handle /aliases Grant Likely
@ 2014-03-14 21:39 ` Rob Herring
0 siblings, 0 replies; 7+ messages in thread
From: Rob Herring @ 2014-03-14 21:39 UTC (permalink / raw)
To: Grant Likely
Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
Pantelis Antoniou, David Daney
On Fri, Mar 14, 2014 at 12:11 PM, Grant Likely <grant.likely@linaro.org> wrote:
> Make of_find_node_by_path() handle aliases as prefixes. To make this
> work the name search is refactored to search by path component instead
> of by full string. This should be a more efficient search, and it makes
> it possible to start a search at a subnode of a tree.
>
> Signed-off-by: David Daney <david.daney@cavium.com>
> Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
> [grant.likely: Rework to not require allocating at runtime]
> Signed-off-by: Grant Likely <grant.likely@linaro.org>
I should have read the comments before trying to figure out why you
had that "pointless" recursion...
Acked-by: Rob Herring <robh@kernel.org>
> ---
> drivers/of/base.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 56 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index 7083fad079a6..b8b673526dbd 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -770,9 +770,38 @@ struct device_node *of_get_child_by_name(const struct device_node *node,
> }
> EXPORT_SYMBOL(of_get_child_by_name);
>
> +static struct device_node *__of_find_node_by_path(struct device_node *parent,
> + const char *path)
> +{
> + struct device_node *child;
> + int len = strchrnul(path, '/') - path;
> +
> + if (!len)
> + return parent;
> +
> + for_each_child_of_node(parent, child) {
> + const char *name = strrchr(child->full_name, '/');
> + if (WARN(!name, "malformed device_node %s\n", child->full_name))
> + continue;
> + name++;
> + if (strncmp(path, name, len) == 0 && (strlen(name) == len))
> + return child;
> + }
> + return NULL;
> +}
> +
> /**
> * of_find_node_by_path - Find a node matching a full OF path
> * @path: The full path to match
> + * @path: Either the full path to match, or if the path does not
> + * start with '/', the name of a property of the /aliases
> + * node (an alias). In the case of an alias, the node
> + * matching the alias' value will be returned.
> + *
> + * Valid paths:
> + * /foo/bar Full path
> + * foo Valid alias
> + * foo/bar Valid alias + relative path
> *
> * Returns a node pointer with refcount incremented, use
> * of_node_put() on it when done.
> @@ -780,13 +809,36 @@ EXPORT_SYMBOL(of_get_child_by_name);
> struct device_node *of_find_node_by_path(const char *path)
> {
> struct device_node *np = of_allnodes;
> + struct property *pp;
> unsigned long flags;
>
> + /* The path could begin with an alias */
> + if (*path != '/') {
> + char *p = strchrnul(path, '/');
> + int len = p - path;
> +
> + /* of_aliases must not be NULL */
> + if (!of_aliases)
> + return NULL;
> +
> + np = NULL;
> + for_each_property_of_node(of_aliases, pp) {
> + if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
> + np = of_find_node_by_path(pp->value);
> + break;
> + }
> + }
> + if (!np)
> + return NULL;
> + path = p;
> + }
> +
> + /* Step down the tree matching path components */
> raw_spin_lock_irqsave(&devtree_lock, flags);
> - for (; np; np = np->allnext) {
> - if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
> - && of_node_get(np))
> - break;
> + while (np && *path == '/') {
> + path++; /* Increment past '/' delimiter */
> + np = __of_find_node_by_path(np, path);
> + path = strchrnul(path, '/');
> }
> raw_spin_unlock_irqrestore(&devtree_lock, flags);
> return np;
> --
> 1.8.3.2
>
> --
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^ permalink raw reply [flat|nested] 7+ messages in thread
[parent not found: < 1394817109-26199-4-git-send-email-grant.likely@linaro.org>]