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author | Pantelis Antoniou <pantelis.antoniou@konsulko.com> | 2014-07-04 19:58:47 +0300 |
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committer | Grant Likely <grant.likely@linaro.org> | 2014-07-16 08:16:17 -0600 |
commit | 698433963b98d6de7b102c242805c99fda4fa1fb (patch) | |
tree | 05a223f160742f6659e47cd5accc245934c941ef /drivers/of | |
parent | 6afc0dc381573559251de9a8259404f49e6aed14 (diff) | |
download | linux-stable-698433963b98d6de7b102c242805c99fda4fa1fb.tar.gz linux-stable-698433963b98d6de7b102c242805c99fda4fa1fb.tar.bz2 linux-stable-698433963b98d6de7b102c242805c99fda4fa1fb.zip |
OF: Utility helper functions for dynamic nodes
Introduce helper functions for working with the live DT tree,
all of them related to dynamically adding/removing nodes and
properties.
__of_prop_dup() copies a property dynamically
__of_node_alloc() creates an empty node
Bug fix about prop->len == 0 by Ionut Nicu <ioan.nicu.ext@nsn.com>
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[glikely: Added unittest for of_copy_property and dropped fine-grained allocations]
[glikely: removed name, type and phandle arguments from __of_node_alloc]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Diffstat (limited to 'drivers/of')
-rw-r--r-- | drivers/of/dynamic.c | 77 | ||||
-rw-r--r-- | drivers/of/of_private.h | 10 | ||||
-rw-r--r-- | drivers/of/selftest.c | 28 |
3 files changed, 115 insertions, 0 deletions
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index 125994330437..e0c4c6e25980 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -214,3 +214,80 @@ void of_node_release(struct kobject *kobj) kfree(node->data); kfree(node); } + +/** + * __of_prop_dup - Copy a property dynamically. + * @prop: Property to copy + * @allocflags: Allocation flags (typically pass GFP_KERNEL) + * + * Copy a property by dynamically allocating the memory of both the + * property stucture and the property name & contents. The property's + * flags have the OF_DYNAMIC bit set so that we can differentiate between + * dynamically allocated properties and not. + * Returns the newly allocated property or NULL on out of memory error. + */ +struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags) +{ + struct property *new; + + new = kzalloc(sizeof(*new), allocflags); + if (!new) + return NULL; + + /* + * NOTE: There is no check for zero length value. + * In case of a boolean property This will allocate a value + * of zero bytes. We do this to work around the use + * of of_get_property() calls on boolean values. + */ + new->name = kstrdup(prop->name, allocflags); + new->value = kmemdup(prop->value, prop->length, allocflags); + new->length = prop->length; + if (!new->name || !new->value) + goto err_free; + + /* mark the property as dynamic */ + of_property_set_flag(new, OF_DYNAMIC); + + return new; + + err_free: + kfree(new->name); + kfree(new->value); + kfree(new); + return NULL; +} + +/** + * __of_node_alloc() - Create an empty device node dynamically. + * @full_name: Full name of the new device node + * @allocflags: Allocation flags (typically pass GFP_KERNEL) + * + * Create an empty device tree node, suitable for further modification. + * The node data are dynamically allocated and all the node flags + * have the OF_DYNAMIC & OF_DETACHED bits set. + * Returns the newly allocated node or NULL on out of memory error. + */ +struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags) +{ + struct device_node *node; + + node = kzalloc(sizeof(*node), allocflags); + if (!node) + return NULL; + + node->full_name = kstrdup(full_name, allocflags); + of_node_set_flag(node, OF_DYNAMIC); + of_node_set_flag(node, OF_DETACHED); + if (!node->full_name) + goto err_free; + + of_node_init(node); + + return node; + + err_free: + kfree(node->full_name); + kfree(node); + return NULL; +} diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index c270f2037779..1799ed2b3808 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -51,4 +51,14 @@ static inline int of_property_notify(int action, struct device_node *np, } #endif /* CONFIG_OF_DYNAMIC */ +/** + * General utilities for working with live trees. + * + * All functions with two leading underscores operate + * without taking node references, so you either have to + * own the devtree lock or work on detached trees only. + */ +struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags); +struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags); + #endif /* _LINUX_OF_PRIVATE_H */ diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c index 077314eebb95..ee2166f0f36a 100644 --- a/drivers/of/selftest.c +++ b/drivers/of/selftest.c @@ -16,6 +16,8 @@ #include <linux/slab.h> #include <linux/device.h> +#include "of_private.h" + static struct selftest_results { int passed; int failed; @@ -266,6 +268,31 @@ static void __init of_selftest_property_match_string(void) selftest(rc == -EILSEQ, "unterminated string; rc=%i", rc); } +#define propcmp(p1, p2) (((p1)->length == (p2)->length) && \ + (p1)->value && (p2)->value && \ + !memcmp((p1)->value, (p2)->value, (p1)->length) && \ + !strcmp((p1)->name, (p2)->name)) +static void __init of_selftest_property_copy(void) +{ +#ifdef CONFIG_OF_DYNAMIC + struct property p1 = { .name = "p1", .length = 0, .value = "" }; + struct property p2 = { .name = "p2", .length = 5, .value = "abcd" }; + struct property *new; + + new = __of_prop_dup(&p1, GFP_KERNEL); + selftest(new && propcmp(&p1, new), "empty property didn't copy correctly\n"); + kfree(new->value); + kfree(new->name); + kfree(new); + + new = __of_prop_dup(&p2, GFP_KERNEL); + selftest(new && propcmp(&p2, new), "non-empty property didn't copy correctly\n"); + kfree(new->value); + kfree(new->name); + kfree(new); +#endif +} + static void __init of_selftest_parse_interrupts(void) { struct device_node *np; @@ -533,6 +560,7 @@ static int __init of_selftest(void) of_selftest_dynamic(); of_selftest_parse_phandle_with_args(); of_selftest_property_match_string(); + of_selftest_property_copy(); of_selftest_parse_interrupts(); of_selftest_parse_interrupts_extended(); of_selftest_match_node(); |