1 files changed, 431 insertions, 0 deletions

diff --git a/drivers/base/property.c b/drivers/base/property.c
new file mode 100644
index 000000000000..c45845874d4f
--- /dev/null
+++ b/drivers/base/property.c
@@ -0,0 +1,431 @@
+/*
+ * property.c - Unified device property interface.
+ *
+ * Copyright (C) 2014, Intel Corporation
+ * Authors: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/property.h>
+#include <linux/export.h>
+#include <linux/acpi.h>
+#include <linux/of.h>
+
+/**
+ * device_property_present - check if a property of a device is present
+ * @dev: Device whose property is being checked
+ * @propname: Name of the property
+ *
+ * Check if property @propname is present in the device firmware description.
+ */
+bool device_property_present(struct device *dev, const char *propname)
+{
+        if (IS_ENABLED(CONFIG_OF) && dev->of_node)
+                return of_property_read_bool(dev->of_node, propname);
+
+        return !acpi_dev_prop_get(ACPI_COMPANION(dev), propname, NULL);
+}
+EXPORT_SYMBOL_GPL(device_property_present);
+
+/**
+ * fwnode_property_present - check if a property of a firmware node is present
+ * @fwnode: Firmware node whose property to check
+ * @propname: Name of the property
+ */
+bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname)
+{
+        if (is_of_node(fwnode))
+                return of_property_read_bool(of_node(fwnode), propname);
+        else if (is_acpi_node(fwnode))
+                return !acpi_dev_prop_get(acpi_node(fwnode), propname, NULL);
+
+        return false;
+}
+EXPORT_SYMBOL_GPL(fwnode_property_present);
+
+#define OF_DEV_PROP_READ_ARRAY(node, propname, type, val, nval) \
+        (val) ? of_property_read_##type##_array((node), (propname), (val), (nval)) \
+              : of_property_count_elems_of_size((node), (propname), sizeof(type))
+
+#define DEV_PROP_READ_ARRAY(_dev_, _propname_, _type_, _proptype_, _val_, _nval_) \
+        IS_ENABLED(CONFIG_OF) && _dev_->of_node ? \
+                (OF_DEV_PROP_READ_ARRAY(_dev_->of_node, _propname_, _type_, \
+                                        _val_, _nval_)) : \
+                acpi_dev_prop_read(ACPI_COMPANION(_dev_), _propname_, \
+                                   _proptype_, _val_, _nval_)
+
+/**
+ * device_property_read_u8_array - return a u8 array property of a device
+ * @dev: Device to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Function reads an array of u8 properties with @propname from the device
+ * firmware description and stores them to @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected.
+ */
+int device_property_read_u8_array(struct device *dev, const char *propname,
+                                  u8 *val, size_t nval)
+{
+        return DEV_PROP_READ_ARRAY(dev, propname, u8, DEV_PROP_U8, val, nval);
+}
+EXPORT_SYMBOL_GPL(device_property_read_u8_array);
+
+/**
+ * device_property_read_u16_array - return a u16 array property of a device
+ * @dev: Device to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Function reads an array of u16 properties with @propname from the device
+ * firmware description and stores them to @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected.
+ */
+int device_property_read_u16_array(struct device *dev, const char *propname,
+                                   u16 *val, size_t nval)
+{
+        return DEV_PROP_READ_ARRAY(dev, propname, u16, DEV_PROP_U16, val, nval);
+}
+EXPORT_SYMBOL_GPL(device_property_read_u16_array);
+
+/**
+ * device_property_read_u32_array - return a u32 array property of a device
+ * @dev: Device to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Function reads an array of u32 properties with @propname from the device
+ * firmware description and stores them to @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected.
+ */
+int device_property_read_u32_array(struct device *dev, const char *propname,
+                                   u32 *val, size_t nval)
+{
+        return DEV_PROP_READ_ARRAY(dev, propname, u32, DEV_PROP_U32, val, nval);
+}
+EXPORT_SYMBOL_GPL(device_property_read_u32_array);
+
+/**
+ * device_property_read_u64_array - return a u64 array property of a device
+ * @dev: Device to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Function reads an array of u64 properties with @propname from the device
+ * firmware description and stores them to @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected.
+ */
+int device_property_read_u64_array(struct device *dev, const char *propname,
+                                   u64 *val, size_t nval)
+{
+        return DEV_PROP_READ_ARRAY(dev, propname, u64, DEV_PROP_U64, val, nval);
+}
+EXPORT_SYMBOL_GPL(device_property_read_u64_array);
+
+/**
+ * device_property_read_string_array - return a string array property of device
+ * @dev: Device to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Function reads an array of string properties with @propname from the device
+ * firmware description and stores them to @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO or %-EILSEQ if the property is not an array of strings,
+ *         %-EOVERFLOW if the size of the property is not as expected.
+ */
+int device_property_read_string_array(struct device *dev, const char *propname,
+                                      const char **val, size_t nval)
+{
+        return IS_ENABLED(CONFIG_OF) && dev->of_node ?
+                of_property_read_string_array(dev->of_node, propname, val, nval) :
+                acpi_dev_prop_read(ACPI_COMPANION(dev), propname,
+                                   DEV_PROP_STRING, val, nval);
+}
+EXPORT_SYMBOL_GPL(device_property_read_string_array);
+
+/**
+ * device_property_read_string - return a string property of a device
+ * @dev: Device to get the property of
+ * @propname: Name of the property
+ * @val: The value is stored here
+ *
+ * Function reads property @propname from the device firmware description and
+ * stores the value into @val if found. The value is checked to be a string.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO or %-EILSEQ if the property type is not a string.
+ */
+int device_property_read_string(struct device *dev, const char *propname,
+                                const char **val)
+{
+        return IS_ENABLED(CONFIG_OF) && dev->of_node ?
+                of_property_read_string(dev->of_node, propname, val) :
+                acpi_dev_prop_read(ACPI_COMPANION(dev), propname,
+                                   DEV_PROP_STRING, val, 1);
+}
+EXPORT_SYMBOL_GPL(device_property_read_string);
+
+#define FWNODE_PROP_READ_ARRAY(_fwnode_, _propname_, _type_, _proptype_, _val_, _nval_) \
+({ \
+        int _ret_; \
+        if (is_of_node(_fwnode_)) \
+                _ret_ = OF_DEV_PROP_READ_ARRAY(of_node(_fwnode_), _propname_, \
+                                               _type_, _val_, _nval_); \
+        else if (is_acpi_node(_fwnode_)) \
+                _ret_ = acpi_dev_prop_read(acpi_node(_fwnode_), _propname_, \
+                                           _proptype_, _val_, _nval_); \
+        else \
+                _ret_ = -ENXIO; \
+        _ret_; \
+})
+
+/**
+ * fwnode_property_read_u8_array - return a u8 array property of firmware node
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Read an array of u8 properties with @propname from @fwnode and stores them to
+ * @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected,
+ *         %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
+                                  const char *propname, u8 *val, size_t nval)
+{
+        return FWNODE_PROP_READ_ARRAY(fwnode, propname, u8, DEV_PROP_U8,
+                                      val, nval);
+}
+EXPORT_SYMBOL_GPL(fwnode_property_read_u8_array);
+
+/**
+ * fwnode_property_read_u16_array - return a u16 array property of firmware node
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Read an array of u16 properties with @propname from @fwnode and store them to
+ * @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected,
+ *         %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_read_u16_array(struct fwnode_handle *fwnode,
+                                   const char *propname, u16 *val, size_t nval)
+{
+        return FWNODE_PROP_READ_ARRAY(fwnode, propname, u16, DEV_PROP_U16,
+                                      val, nval);
+}
+EXPORT_SYMBOL_GPL(fwnode_property_read_u16_array);
+
+/**
+ * fwnode_property_read_u32_array - return a u32 array property of firmware node
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Read an array of u32 properties with @propname from @fwnode store them to
+ * @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected,
+ *         %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_read_u32_array(struct fwnode_handle *fwnode,
+                                   const char *propname, u32 *val, size_t nval)
+{
+        return FWNODE_PROP_READ_ARRAY(fwnode, propname, u32, DEV_PROP_U32,
+                                      val, nval);
+}
+EXPORT_SYMBOL_GPL(fwnode_property_read_u32_array);
+
+/**
+ * fwnode_property_read_u64_array - return a u64 array property firmware node
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Read an array of u64 properties with @propname from @fwnode and store them to
+ * @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of numbers,
+ *         %-EOVERFLOW if the size of the property is not as expected,
+ *         %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_read_u64_array(struct fwnode_handle *fwnode,
+                                   const char *propname, u64 *val, size_t nval)
+{
+        return FWNODE_PROP_READ_ARRAY(fwnode, propname, u64, DEV_PROP_U64,
+                                      val, nval);
+}
+EXPORT_SYMBOL_GPL(fwnode_property_read_u64_array);
+
+/**
+ * fwnode_property_read_string_array - return string array property of a node
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property
+ * @val: The values are stored here
+ * @nval: Size of the @val array
+ *
+ * Read an string list property @propname from the given firmware node and store
+ * them to @val if found.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO if the property is not an array of strings,
+ *         %-EOVERFLOW if the size of the property is not as expected,
+ *         %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
+                                      const char *propname, const char **val,
+                                      size_t nval)
+{
+        if (is_of_node(fwnode))
+                return of_property_read_string_array(of_node(fwnode), propname,
+                                                     val, nval);
+        else if (is_acpi_node(fwnode))
+                return acpi_dev_prop_read(acpi_node(fwnode), propname,
+                                          DEV_PROP_STRING, val, nval);
+
+        return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(fwnode_property_read_string_array);
+
+/**
+ * fwnode_property_read_string - return a string property of a firmware node
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property
+ * @val: The value is stored here
+ *
+ * Read property @propname from the given firmware node and store the value into
+ * @val if found.  The value is checked to be a string.
+ *
+ * Return: %0 if the property was found (success),
+ *         %-EINVAL if given arguments are not valid,
+ *         %-ENODATA if the property does not have a value,
+ *         %-EPROTO or %-EILSEQ if the property is not a string,
+ *         %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_read_string(struct fwnode_handle *fwnode,
+                                const char *propname, const char **val)
+{
+        if (is_of_node(fwnode))
+                return of_property_read_string(of_node(fwnode),propname, val);
+        else if (is_acpi_node(fwnode))
+                return acpi_dev_prop_read(acpi_node(fwnode), propname,
+                                          DEV_PROP_STRING, val, 1);
+
+        return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(fwnode_property_read_string);
+
+/**
+ * device_get_next_child_node - Return the next child node handle for a device
+ * @dev: Device to find the next child node for.
+ * @child: Handle to one of the device's child nodes or a null handle.
+ */
+struct fwnode_handle *device_get_next_child_node(struct device *dev,
+                                                 struct fwnode_handle *child)
+{
+        if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
+                struct device_node *node;
+
+                node = of_get_next_available_child(dev->of_node, of_node(child));
+                if (node)
+                        return &node->fwnode;
+        } else if (IS_ENABLED(CONFIG_ACPI)) {
+                struct acpi_device *node;
+
+                node = acpi_get_next_child(dev, acpi_node(child));
+                if (node)
+                        return acpi_fwnode_handle(node);
+        }
+        return NULL;
+}
+EXPORT_SYMBOL_GPL(device_get_next_child_node);
+
+/**
+ * fwnode_handle_put - Drop reference to a device node
+ * @fwnode: Pointer to the device node to drop the reference to.
+ *
+ * This has to be used when terminating device_for_each_child_node() iteration
+ * with break or return to prevent stale device node references from being left
+ * behind.
+ */
+void fwnode_handle_put(struct fwnode_handle *fwnode)
+{
+        if (is_of_node(fwnode))
+                of_node_put(of_node(fwnode));
+}
+EXPORT_SYMBOL_GPL(fwnode_handle_put);
+
+/**
+ * device_get_child_node_count - return the number of child nodes for device
+ * @dev: Device to cound the child nodes for
+ */
+unsigned int device_get_child_node_count(struct device *dev)
+{
+        struct fwnode_handle *child;
+        unsigned int count = 0;
+
+        device_for_each_child_node(dev, child)
+                count++;
+
+        return count;
+}
+EXPORT_SYMBOL_GPL(device_get_child_node_count);