[PATCHv5 2/7] of: Remove duplicated code for validating property and value

Tony Prisk
2013-04-03T06:26:28Z

Several functions in of/base.c have the same code duplicated for
finding and validating a property and value.

struct property *prop = of_find_property(np, propname, NULL);
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (<some length> > prop->length)
return -EOVERFLOW;

This patch adds of_find_property_value_of_size() which performs the
equivalent of the above code and removes the instances where it was
duplicated in several functions.

Reported-by: Rob Herring <robherring2@gmail.com>
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
---
drivers/of/base.c | 94 +++++++++++++++++++++++++++++------------------------
1 file changed, 51 insertions(+), 43 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index f6c89ed..c6443de 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -746,6 +746,34 @@ struct device_node *of_find_node_by_phandle(phandle handle)
EXPORT_SYMBOL(of_find_node_by_phandle);

/**
+ * of_find_property_value_of_size
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @len: requested length of property value
+ *
+ * Search for a property in a device node and valid the requested size.
+ * Returns the property value on success, -EINVAL if the property does not
+ * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ */
+static void *of_find_property_value_of_size(const struct device_node *np,
+ const char *propname, u32 len)
+{
+ struct property *prop = of_find_property(np, propname, NULL);
+
+ if (!prop)
+ return ERR_PTR(-EINVAL);
+ if (!prop->value)
+ return ERR_PTR(-ENODATA);
+ if (len > prop->length)
+ return ERR_PTR(-EOVERFLOW);
+
+ return prop->value;
+}
+
+/**
* of_property_read_u32_index - Find and read a u32 from a multi-value property.
*
* @np: device node from which the property value is to be read.
@@ -764,16 +792,13 @@ int of_property_read_u32_index(const struct device_node *np,
const char *propname,
u32 index, u32 *out_value)
{
- struct property *prop = of_find_property(np, propname, NULL);
+ const u32 *val = of_find_property_value_of_size(np, propname,
+ ((index + 1) * sizeof(*out_value)));

- if (!prop)
- return -EINVAL;
- if (!prop->value)
- return -ENODATA;
- if (((index + 1) * sizeof(*out_value)) > prop->length)
- return -EOVERFLOW;
+ if (IS_ERR(val))
+ return PTR_ERR(val);

- *out_value = be32_to_cpup(((__be32 *)prop->value) + index);
+ *out_value = be32_to_cpup(((__be32 *)val) + index);
return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u32_index);
@@ -799,17 +824,12 @@ EXPORT_SYMBOL_GPL(of_property_read_u32_index);
int of_property_read_u8_array(const struct device_node *np,
const char *propname, u8 *out_values, size_t sz)
{
- struct property *prop = of_find_property(np, propname, NULL);
- const u8 *val;
+ const u8 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));

- if (!prop)
- return -EINVAL;
- if (!prop->value)
- return -ENODATA;
- if ((sz * sizeof(*out_values)) > prop->length)
- return -EOVERFLOW;
+ if (IS_ERR(val))
+ return PTR_ERR(val);

- val = prop->value;
while (sz--)
*out_values++ = *val++;
return 0;
@@ -837,17 +857,12 @@ EXPORT_SYMBOL_GPL(of_property_read_u8_array);
int of_property_read_u16_array(const struct device_node *np,
const char *propname, u16 *out_values, size_t sz)
{
- struct property *prop = of_find_property(np, propname, NULL);
- const __be16 *val;
+ const __be16 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));

- if (!prop)
- return -EINVAL;
- if (!prop->value)
- return -ENODATA;
- if ((sz * sizeof(*out_values)) > prop->length)
- return -EOVERFLOW;
+ if (IS_ERR(val))
+ return PTR_ERR(val);

- val = prop->value;
while (sz--)
*out_values++ = be16_to_cpup(val++);
return 0;
@@ -874,17 +889,12 @@ int of_property_read_u32_array(const struct device_node *np,
const char *propname, u32 *out_values,
size_t sz)
{
- struct property *prop = of_find_property(np, propname, NULL);
- const __be32 *val;
+ const __be32 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));

- if (!prop)
- return -EINVAL;
- if (!prop->value)
- return -ENODATA;
- if ((sz * sizeof(*out_values)) > prop->length)
- return -EOVERFLOW;
+ if (IS_ERR(val))
+ return PTR_ERR(val);

- val = prop->value;
while (sz--)
*out_values++ = be32_to_cpup(val++);
return 0;
@@ -907,15 +917,13 @@ EXPORT_SYMBOL_GPL(of_property_read_u32_array);
int of_property_read_u64(const struct device_node *np, const char *propname,
u64 *out_value)
{
- struct property *prop = of_find_property(np, propname, NULL);
+ const __be32 *val = of_find_property_value_of_size(np, propname,
+ sizeof(*out_value));

- if (!prop)
- return -EINVAL;
- if (!prop->value)
- return -ENODATA;
- if (sizeof(*out_value) > prop->length)
- return -EOVERFLOW;
- *out_value = of_read_number(prop->value, 2);
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ *out_value = of_read_number(val, 2);
return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u64);
--
1.7.9.5