[PATCH v1] device property: Add helpers to count items in an array

[Andy Shevchenko]

The usual pattern to allocate the necessary space for an array of properties is
to count them fist using:

  count = device_property_read_uXX_array(dev, propname, NULL, 0);

Introduce helpers device_property_count_uXX() to count items by supplying hard
coded last two parameters to device_property_readXX_array().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 include/linux/property.h | 44 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/include/linux/property.h b/include/linux/property.h
index a29369c89e6e..65e31c090f9f 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -144,6 +144,26 @@ static inline int device_property_read_u64(struct device *dev,
 	return device_property_read_u64_array(dev, propname, val, 1);
 }
 
+static inline int device_property_count_u8(struct device *dev, const char *propname)
+{
+	return device_property_read_u8_array(dev, propname, NULL, 0);
+}
+
+static inline int device_property_count_u16(struct device *dev, const char *propname)
+{
+	return device_property_read_u16_array(dev, propname, NULL, 0);
+}
+
+static inline int device_property_count_u32(struct device *dev, const char *propname)
+{
+	return device_property_read_u32_array(dev, propname, NULL, 0);
+}
+
+static inline int device_property_count_u64(struct device *dev, const char *propname)
+{
+	return device_property_read_u64_array(dev, propname, NULL, 0);
+}
+
 static inline bool fwnode_property_read_bool(const struct fwnode_handle *fwnode,
 					     const char *propname)
 {
@@ -174,6 +194,30 @@ static inline int fwnode_property_read_u64(const struct fwnode_handle *fwnode,
 	return fwnode_property_read_u64_array(fwnode, propname, val, 1);
 }
 
+static inline int fwnode_property_count_u8(const struct fwnode_handle *fwnode,
+					   const char *propname)
+{
+	return fwnode_property_read_u8_array(fwnode, propname, NULL, 0);
+}
+
+static inline int fwnode_property_count_u16(const struct fwnode_handle *fwnode,
+					    const char *propname)
+{
+	return fwnode_property_read_u16_array(fwnode, propname, NULL, 0);
+}
+
+static inline int fwnode_property_count_u32(const struct fwnode_handle *fwnode,
+					    const char *propname)
+{
+	return fwnode_property_read_u32_array(fwnode, propname, NULL, 0);
+}
+
+static inline int fwnode_property_count_u64(const struct fwnode_handle *fwnode,
+					    const char *propname)
+{
+	return fwnode_property_read_u64_array(fwnode, propname, NULL, 0);
+}
+
 /**
  * struct property_entry - "Built-in" device property representation.
  * @name: Name of the property.
-- 
2.20.1