of: Make of_find_property_value_of_size take a length range

index 3ce6953..b853737 100644
@@ -1146,16 +1146,18 @@ EXPORT_SYMBOL_GPL(of_property_count_elems_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
+ * @min:	minimum allowed length of property value
+ * @max:	maximum allowed length of property value (0 means unlimited)
+ * @len:	if !=NULL, actual length is written to here
  *
  * 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.
+ * property data is too small or too large.
  *
  */
 static void *of_find_property_value_of_size(const struct device_node *np,
-			const char *propname, u32 len)
+			const char *propname, u32 min, u32 max, size_t *len)
 {
 	struct property *prop = of_find_property(np, propname, NULL);
 

@@ -1163,9 +1165,14 @@ static void *of_find_property_value_of_size(const struct device_node *np,
 		return ERR_PTR(-EINVAL);
 	if (!prop->value)
 		return ERR_PTR(-ENODATA);
-	if (len > prop->length)
+	if (prop->length < min)
+		return ERR_PTR(-EOVERFLOW);
+	if (max && prop->length > max)
 		return ERR_PTR(-EOVERFLOW);
 
+	if (len)
+		*len = prop->length;
+
 	return prop->value;
 }
 

@@ -1189,7 +1196,9 @@ int of_property_read_u32_index(const struct device_node *np,
 				       u32 index, u32 *out_value)
 {
 	const u32 *val = of_find_property_value_of_size(np, propname,
-					((index + 1) * sizeof(*out_value)));
+					((index + 1) * sizeof(*out_value)),
+					0,
+					NULL);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);

@@ -1221,7 +1230,9 @@ int of_property_read_u8_array(const struct device_node *np,
 			const char *propname, u8 *out_values, size_t sz)
 {
 	const u8 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)));
+						(sz * sizeof(*out_values)),
+						0,
+						NULL);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);

@@ -1254,7 +1265,9 @@ int of_property_read_u16_array(const struct device_node *np,
 			const char *propname, u16 *out_values, size_t sz)
 {
 	const __be16 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)));
+						(sz * sizeof(*out_values)),
+						0,
+						NULL);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);

@@ -1286,7 +1299,9 @@ int of_property_read_u32_array(const struct device_node *np,
 			       size_t sz)
 {
 	const __be32 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)));
+						(sz * sizeof(*out_values)),
+						0,
+						NULL);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);

@@ -1314,7 +1329,9 @@ int of_property_read_u64(const struct device_node *np, const char *propname,
 			 u64 *out_value)
 {
 	const __be32 *val = of_find_property_value_of_size(np, propname,
-						sizeof(*out_value));
+						sizeof(*out_value),
+						0,
+						NULL);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);

@@ -1345,7 +1362,9 @@ int of_property_read_u64_array(const struct device_node *np,
 			       size_t sz)
 {
 	const __be32 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)));
+						(sz * sizeof(*out_values)),
+						0,
+						NULL);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);

index b853737..a0bccb5 100644
@@ -1209,108 +1209,145 @@ int of_property_read_u32_index(const struct device_node *np,
 EXPORT_SYMBOL_GPL(of_property_read_u32_index);
 
 /**
- * of_property_read_u8_array - Find and read an array of u8 from a property.
+ * of_property_read_variable_u8_array - Find and read an array of u8 from a
+ * property, with bounds on the minimum and maximum array size.
  *
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  * @out_values:	pointer to return value, modified only if return value is 0.
- * @sz:		number of array elements to read
+ * @sz_min:	minimum number of array elements to read
+ * @sz_max:	maximum number of array elements to read, if zero there is no
+ *		upper limit on the number of elements in the dts entry but only
+ *		sz_min will be read.
  *
  * Search for a property in a device node and read 8-bit value(s) from
- * it. Returns 0 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.
+ * it. Returns number of elements read on success, -EINVAL if the property
+ * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
+ * if the property data is smaller than sz_min or longer than sz_max.
  *
  * dts entry of array should be like:
  *	property = /bits/ 8 <0x50 0x60 0x70>;
  *
  * The out_values is modified only if a valid u8 value can be decoded.
  */
-int of_property_read_u8_array(const struct device_node *np,
-			const char *propname, u8 *out_values, size_t sz)
+int of_property_read_variable_u8_array(const struct device_node *np,
+					const char *propname, u8 *out_values,
+					size_t sz_min, size_t sz_max)
 {
+	size_t sz, count;
 	const u8 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)),
-						0,
-						NULL);
+						(sz_min * sizeof(*out_values)),
+						(sz_max * sizeof(*out_values)),
+						&sz);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);
 
-	while (sz--)
+	if (!sz_max)
+		sz = sz_min;
+	else
+		sz /= sizeof(*out_values);
+
+	count = sz;
+	while (count--)
 		*out_values++ = *val++;
-	return 0;
+
+	return sz;
 }
-EXPORT_SYMBOL_GPL(of_property_read_u8_array);
+EXPORT_SYMBOL_GPL(of_property_read_variable_u8_array);
 
 /**
- * of_property_read_u16_array - Find and read an array of u16 from a property.
+ * of_property_read_variable_u16_array - Find and read an array of u16 from a
+ * property, with bounds on the minimum and maximum array size.
  *
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  * @out_values:	pointer to return value, modified only if return value is 0.
- * @sz:		number of array elements to read
+ * @sz_min:	minimum number of array elements to read
+ * @sz_max:	maximum number of array elements to read, if zero there is no
+ *		upper limit on the number of elements in the dts entry but only
+ *		sz_min will be read.
  *
  * Search for a property in a device node and read 16-bit value(s) from
- * it. Returns 0 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.
+ * it. Returns number of elements read on success, -EINVAL if the property
+ * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
+ * if the property data is smaller than sz_min or longer than sz_max.
  *
  * dts entry of array should be like:
  *	property = /bits/ 16 <0x5000 0x6000 0x7000>;
  *
  * The out_values is modified only if a valid u16 value can be decoded.
  */
-int of_property_read_u16_array(const struct device_node *np,
-			const char *propname, u16 *out_values, size_t sz)
+int of_property_read_variable_u16_array(const struct device_node *np,
+					const char *propname, u16 *out_values,
+					size_t sz_min, size_t sz_max)
 {
+	size_t sz, count;
 	const __be16 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)),
-						0,
-						NULL);
+						(sz_min * sizeof(*out_values)),
+						(sz_max * sizeof(*out_values)),
+						&sz);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);
 
-	while (sz--)
+	if (!sz_max)
+		sz = sz_min;
+	else
+		sz /= sizeof(*out_values);
+
+	count = sz;
+	while (count--)
 		*out_values++ = be16_to_cpup(val++);
-	return 0;
+
+	return sz;
 }
-EXPORT_SYMBOL_GPL(of_property_read_u16_array);
+EXPORT_SYMBOL_GPL(of_property_read_variable_u16_array);
 
 /**
- * of_property_read_u32_array - Find and read an array of 32 bit integers
- * from a property.
+ * of_property_read_variable_u32_array - Find and read an array of 32 bit
+ * integers from a property, with bounds on the minimum and maximum array size.
  *
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  * @out_values:	pointer to return value, modified only if return value is 0.
- * @sz:		number of array elements to read
+ * @sz_min:	minimum number of array elements to read
+ * @sz_max:	maximum number of array elements to read, if zero there is no
+ *		upper limit on the number of elements in the dts entry but only
+ *		sz_min will be read.
  *
  * Search for a property in a device node and read 32-bit value(s) from
- * it. Returns 0 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.
+ * it. Returns number of elements read on success, -EINVAL if the property
+ * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
+ * if the property data is smaller than sz_min or longer than sz_max.
  *
  * The out_values is modified only if a valid u32 value can be decoded.
  */
-int of_property_read_u32_array(const struct device_node *np,
+int of_property_read_variable_u32_array(const struct device_node *np,
 			       const char *propname, u32 *out_values,
-			       size_t sz)
+			       size_t sz_min, size_t sz_max)
 {
+	size_t sz, count;
 	const __be32 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)),
-						0,
-						NULL);
+						(sz_min * sizeof(*out_values)),
+						(sz_max * sizeof(*out_values)),
+						&sz);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);
 
-	while (sz--)
+	if (!sz_max)
+		sz = sz_min;
+	else
+		sz /= sizeof(*out_values);
+
+	count = sz;
+	while (count--)
 		*out_values++ = be32_to_cpup(val++);
-	return 0;
+
+	return sz;
 }
-EXPORT_SYMBOL_GPL(of_property_read_u32_array);
+EXPORT_SYMBOL_GPL(of_property_read_variable_u32_array);
 
 /**
  * of_property_read_u64 - Find and read a 64 bit integer from a property

@@ -1342,40 +1379,51 @@ int of_property_read_u64(const struct device_node *np, const char *propname,
 EXPORT_SYMBOL_GPL(of_property_read_u64);
 
 /**
- * of_property_read_u64_array - Find and read an array of 64 bit integers
- * from a property.
+ * of_property_read_variable_u64_array - Find and read an array of 64 bit
+ * integers from a property, with bounds on the minimum and maximum array size.
  *
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  * @out_values:	pointer to return value, modified only if return value is 0.
- * @sz:		number of array elements to read
+ * @sz_min:	minimum number of array elements to read
+ * @sz_max:	maximum number of array elements to read, if zero there is no
+ *		upper limit on the number of elements in the dts entry but only
+ *		sz_min will be read.
  *
  * Search for a property in a device node and read 64-bit value(s) from
- * it. Returns 0 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.
+ * it. Returns number of elements read on success, -EINVAL if the property
+ * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
+ * if the property data is smaller than sz_min or longer than sz_max.
  *
  * The out_values is modified only if a valid u64 value can be decoded.
  */
-int of_property_read_u64_array(const struct device_node *np,
+int of_property_read_variable_u64_array(const struct device_node *np,
 			       const char *propname, u64 *out_values,
-			       size_t sz)
+			       size_t sz_min, size_t sz_max)
 {
+	size_t sz, count;
 	const __be32 *val = of_find_property_value_of_size(np, propname,
-						(sz * sizeof(*out_values)),
-						0,
-						NULL);
+						(sz_min * sizeof(*out_values)),
+						(sz_max * sizeof(*out_values)),
+						&sz);
 
 	if (IS_ERR(val))
 		return PTR_ERR(val);
 
-	while (sz--) {
+	if (!sz_max)
+		sz = sz_min;
+	else
+		sz /= sizeof(*out_values);
+
+	count = sz;
+	while (count--) {
 		*out_values++ = of_read_number(val, 2);
 		val += 2;
 	}
-	return 0;
+
+	return sz;
 }
-EXPORT_SYMBOL_GPL(of_property_read_u64_array);
+EXPORT_SYMBOL_GPL(of_property_read_variable_u64_array);
 
 /**
  * of_property_read_string - Find and read a string from a property

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