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+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2013 Google, Inc
+ *
+ * (C) Copyright 2012
+ * Pavel Herrmann <morpheus.ibis@gmail.com>
+ * Marek Vasut <marex@denx.de>
+ */
+
+#ifndef _DM_DEVICE_H
+#define _DM_DEVICE_H
+
+#include <dm/ofnode.h>
+#include <dm/uclass-id.h>
+#include <fdtdec.h>
+#include <linker_lists.h>
+#include <linux/compat.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/printk.h>
+
+struct driver_info;
+
+/* Driver is active (probed). Cleared when it is removed */
+#define DM_FLAG_ACTIVATED (1 << 0)
+
+/* DM is responsible for allocating and freeing platdata */
+#define DM_FLAG_ALLOC_PDATA (1 << 1)
+
+/* DM should init this device prior to relocation */
+#define DM_FLAG_PRE_RELOC (1 << 2)
+
+/* DM is responsible for allocating and freeing parent_platdata */
+#define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
+
+/* DM is responsible for allocating and freeing uclass_platdata */
+#define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4)
+
+/* Allocate driver private data on a DMA boundary */
+#define DM_FLAG_ALLOC_PRIV_DMA (1 << 5)
+
+/* Device is bound */
+#define DM_FLAG_BOUND (1 << 6)
+
+/* Device name is allocated and should be freed on unbind() */
+#define DM_FLAG_NAME_ALLOCED (1 << 7)
+
+#define DM_FLAG_OF_PLATDATA (1 << 8)
+
+/*
+ * Call driver remove function to stop currently active DMA transfers or
+ * give DMA buffers back to the HW / controller. This may be needed for
+ * some drivers to do some final stage cleanup before the OS is called
+ * (U-Boot exit)
+ */
+#define DM_FLAG_ACTIVE_DMA (1 << 9)
+
+/*
+ * Call driver remove function to do some final configuration, before
+ * U-Boot exits and the OS is started
+ */
+#define DM_FLAG_OS_PREPARE (1 << 10)
+
+/* DM does not enable/disable the power domains corresponding to this device */
+#define DM_FLAG_DEFAULT_PD_CTRL_OFF (1 << 11)
+
+/*
+ * One or multiple of these flags are passed to device_remove() so that
+ * a selective device removal as specified by the remove-stage and the
+ * driver flags can be done.
+ */
+enum {
+ /* Normal remove, remove all devices */
+ DM_REMOVE_NORMAL = 1 << 0,
+
+ /* Remove devices with active DMA */
+ DM_REMOVE_ACTIVE_DMA = DM_FLAG_ACTIVE_DMA,
+
+ /* Remove devices which need some final OS preparation steps */
+ DM_REMOVE_OS_PREPARE = DM_FLAG_OS_PREPARE,
+
+ /* Add more use cases here */
+
+ /* Remove devices with any active flag */
+ DM_REMOVE_ACTIVE_ALL = DM_REMOVE_ACTIVE_DMA | DM_REMOVE_OS_PREPARE,
+};
+
+/**
+ * struct udevice - An instance of a driver
+ *
+ * This holds information about a device, which is a driver bound to a
+ * particular port or peripheral (essentially a driver instance).
+ *
+ * A device will come into existence through a 'bind' call, either due to
+ * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node
+ * in the device tree (in which case of_offset is >= 0). In the latter case
+ * we translate the device tree information into platdata in a function
+ * implemented by the driver ofdata_to_platdata method (called just before the
+ * probe method if the device has a device tree node.
+ *
+ * All three of platdata, priv and uclass_priv can be allocated by the
+ * driver, or you can use the auto_alloc_size members of struct driver and
+ * struct uclass_driver to have driver model do this automatically.
+ *
+ * @driver: The driver used by this device
+ * @name: Name of device, typically the FDT node name
+ * @platdata: Configuration data for this device
+ * @parent_platdata: The parent bus's configuration data for this device
+ * @uclass_platdata: The uclass's configuration data for this device
+ * @node: Reference to device tree node for this device
+ * @driver_data: Driver data word for the entry that matched this device with
+ * its driver
+ * @parent: Parent of this device, or NULL for the top level device
+ * @priv: Private data for this device
+ * @uclass: Pointer to uclass for this device
+ * @uclass_priv: The uclass's private data for this device
+ * @parent_priv: The parent's private data for this device
+ * @uclass_node: Used by uclass to link its devices
+ * @child_head: List of children of this device
+ * @sibling_node: Next device in list of all devices
+ * @flags: Flags for this device DM_FLAG_...
+ * @req_seq: Requested sequence number for this device (-1 = any)
+ * @seq: Allocated sequence number for this device (-1 = none). This is set up
+ * when the device is probed and will be unique within the device's uclass.
+ * @devres_head: List of memory allocations associated with this device.
+ * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
+ * add to this list. Memory so-allocated will be freed
+ * automatically when the device is removed / unbound
+ */
+struct udevice {
+ const struct driver *driver;
+ const char *name;
+ void *platdata;
+ void *parent_platdata;
+ void *uclass_platdata;
+ ofnode node;
+ ulong driver_data;
+ struct udevice *parent;
+ void *priv;
+ struct uclass *uclass;
+ void *uclass_priv;
+ void *parent_priv;
+ struct list_head uclass_node;
+ struct list_head child_head;
+ struct list_head sibling_node;
+ uint32_t flags;
+ int req_seq;
+ int seq;
+#ifdef CONFIG_DEVRES
+ struct list_head devres_head;
+#endif
+};
+
+/* Maximum sequence number supported */
+#define DM_MAX_SEQ 999
+
+/* Returns the operations for a device */
+#define device_get_ops(dev) (dev->driver->ops)
+
+/* Returns non-zero if the device is active (probed and not removed) */
+#define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED)
+
+static inline int dev_of_offset(const struct udevice *dev)
+{
+ return ofnode_to_offset(dev->node);
+}
+
+static inline void dev_set_of_offset(struct udevice *dev, int of_offset)
+{
+ dev->node = offset_to_ofnode(of_offset);
+}
+
+static inline bool dev_has_of_node(struct udevice *dev)
+{
+ return ofnode_valid(dev->node);
+}
+
+/**
+ * struct udevice_id - Lists the compatible strings supported by a driver
+ * @compatible: Compatible string
+ * @data: Data for this compatible string
+ */
+struct udevice_id {
+ const char *compatible;
+ ulong data;
+};
+
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+#define of_match_ptr(_ptr) (_ptr)
+#else
+#define of_match_ptr(_ptr) NULL
+#endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
+
+/**
+ * struct driver - A driver for a feature or peripheral
+ *
+ * This holds methods for setting up a new device, and also removing it.
+ * The device needs information to set itself up - this is provided either
+ * by platdata or a device tree node (which we find by looking up
+ * matching compatible strings with of_match).
+ *
+ * Drivers all belong to a uclass, representing a class of devices of the
+ * same type. Common elements of the drivers can be implemented in the uclass,
+ * or the uclass can provide a consistent interface to the drivers within
+ * it.
+ *
+ * @name: Device name
+ * @id: Identifies the uclass we belong to
+ * @of_match: List of compatible strings to match, and any identifying data
+ * for each.
+ * @bind: Called to bind a device to its driver
+ * @probe: Called to probe a device, i.e. activate it
+ * @remove: Called to remove a device, i.e. de-activate it
+ * @unbind: Called to unbind a device from its driver
+ * @ofdata_to_platdata: Called before probe to decode device tree data
+ * @child_post_bind: Called after a new child has been bound
+ * @child_pre_probe: Called before a child device is probed. The device has
+ * memory allocated but it has not yet been probed.
+ * @child_post_remove: Called after a child device is removed. The device
+ * has memory allocated but its device_remove() method has been called.
+ * @priv_auto_alloc_size: If non-zero this is the size of the private data
+ * to be allocated in the device's ->priv pointer. If zero, then the driver
+ * is responsible for allocating any data required.
+ * @platdata_auto_alloc_size: If non-zero this is the size of the
+ * platform data to be allocated in the device's ->platdata pointer.
+ * This is typically only useful for device-tree-aware drivers (those with
+ * an of_match), since drivers which use platdata will have the data
+ * provided in the U_BOOT_DEVICE() instantiation.
+ * @per_child_auto_alloc_size: Each device can hold private data owned by
+ * its parent. If required this will be automatically allocated if this
+ * value is non-zero.
+ * @per_child_platdata_auto_alloc_size: A bus likes to store information about
+ * its children. If non-zero this is the size of this data, to be allocated
+ * in the child's parent_platdata pointer.
+ * @ops: Driver-specific operations. This is typically a list of function
+ * pointers defined by the driver, to implement driver functions required by
+ * the uclass.
+ * @flags: driver flags - see DM_FLAGS_...
+ */
+struct driver {
+ char *name;
+ enum uclass_id id;
+ const struct udevice_id *of_match;
+ int (*bind)(struct udevice *dev);
+ int (*probe)(struct udevice *dev);
+ int (*remove)(struct udevice *dev);
+ int (*unbind)(struct udevice *dev);
+ int (*ofdata_to_platdata)(struct udevice *dev);
+ int (*child_post_bind)(struct udevice *dev);
+ int (*child_pre_probe)(struct udevice *dev);
+ int (*child_post_remove)(struct udevice *dev);
+ int priv_auto_alloc_size;
+ int platdata_auto_alloc_size;
+ int per_child_auto_alloc_size;
+ int per_child_platdata_auto_alloc_size;
+ const void *ops; /* driver-specific operations */
+ uint32_t flags;
+};
+
+/* Declare a new U-Boot driver */
+#define U_BOOT_DRIVER(__name) \
+ ll_entry_declare(struct driver, __name, driver)
+
+/* Get a pointer to a given driver */
+#define DM_GET_DRIVER(__name) \
+ ll_entry_get(struct driver, __name, driver)
+
+/**
+ * dev_get_platdata() - Get the platform data for a device
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev Device to check
+ * @return platform data, or NULL if none
+ */
+void *dev_get_platdata(const struct udevice *dev);
+
+/**
+ * dev_get_parent_platdata() - Get the parent platform data for a device
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev Device to check
+ * @return parent's platform data, or NULL if none
+ */
+void *dev_get_parent_platdata(const struct udevice *dev);
+
+/**
+ * dev_get_uclass_platdata() - Get the uclass platform data for a device
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev Device to check
+ * @return uclass's platform data, or NULL if none
+ */
+void *dev_get_uclass_platdata(const struct udevice *dev);
+
+/**
+ * dev_get_priv() - Get the private data for a device
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev Device to check
+ * @return private data, or NULL if none
+ */
+void *dev_get_priv(const struct udevice *dev);
+
+/**
+ * dev_get_parent_priv() - Get the parent private data for a device
+ *
+ * The parent private data is data stored in the device but owned by the
+ * parent. For example, a USB device may have parent data which contains
+ * information about how to talk to the device over USB.
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev Device to check
+ * @return parent data, or NULL if none
+ */
+void *dev_get_parent_priv(const struct udevice *dev);
+
+/**
+ * dev_get_uclass_priv() - Get the private uclass data for a device
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev Device to check
+ * @return private uclass data for this device, or NULL if none
+ */
+void *dev_get_uclass_priv(const struct udevice *dev);
+
+/**
+ * struct dev_get_parent() - Get the parent of a device
+ *
+ * @child: Child to check
+ * @return parent of child, or NULL if this is the root device
+ */
+struct udevice *dev_get_parent(const struct udevice *child);
+
+/**
+ * dev_get_driver_data() - get the driver data used to bind a device
+ *
+ * When a device is bound using a device tree node, it matches a
+ * particular compatible string in struct udevice_id. This function
+ * returns the associated data value for that compatible string. This is
+ * the 'data' field in struct udevice_id.
+ *
+ * As an example, consider this structure:
+ * static const struct udevice_id tegra_i2c_ids[] = {
+ * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
+ * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
+ * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
+ * { }
+ * };
+ *
+ * When driver model finds a driver for this it will store the 'data' value
+ * corresponding to the compatible string it matches. This function returns
+ * that value. This allows the driver to handle several variants of a device.
+ *
+ * For USB devices, this is the driver_info field in struct usb_device_id.
+ *
+ * @dev: Device to check
+ * @return driver data (0 if none is provided)
+ */
+ulong dev_get_driver_data(const struct udevice *dev);
+
+/**
+ * dev_get_driver_ops() - get the device's driver's operations
+ *
+ * This checks that dev is not NULL, and returns the pointer to device's
+ * driver's operations.
+ *
+ * @dev: Device to check
+ * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
+ */
+const void *dev_get_driver_ops(const struct udevice *dev);
+
+/**
+ * device_get_uclass_id() - return the uclass ID of a device
+ *
+ * @dev: Device to check
+ * @return uclass ID for the device
+ */
+enum uclass_id device_get_uclass_id(const struct udevice *dev);
+
+/**
+ * dev_get_uclass_name() - return the uclass name of a device
+ *
+ * This checks that dev is not NULL.
+ *
+ * @dev: Device to check
+ * @return pointer to the uclass name for the device
+ */
+const char *dev_get_uclass_name(const struct udevice *dev);
+
+/**
+ * device_get_child() - Get the child of a device by index
+ *
+ * Returns the numbered child, 0 being the first. This does not use
+ * sequence numbers, only the natural order.
+ *
+ * @dev: Parent device to check
+ * @index: Child index
+ * @devp: Returns pointer to device
+ * @return 0 if OK, -ENODEV if no such device, other error if the device fails
+ * to probe
+ */
+int device_get_child(struct udevice *parent, int index, struct udevice **devp);
+
+/**
+ * device_get_child_count() - Get the available child count of a device
+ *
+ * Returns the number of children to a device.
+ *
+ * @parent: Parent device to check
+ */
+int device_get_child_count(struct udevice *parent);
+
+/**
+ * device_find_child_by_seq() - Find a child device based on a sequence
+ *
+ * This searches for a device with the given seq or req_seq.
+ *
+ * For seq, if an active device has this sequence it will be returned.
+ * If there is no such device then this will return -ENODEV.
+ *
+ * For req_seq, if a device (whether activated or not) has this req_seq
+ * value, that device will be returned. This is a strong indication that
+ * the device will receive that sequence when activated.
+ *
+ * @parent: Parent device
+ * @seq_or_req_seq: Sequence number to find (0=first)
+ * @find_req_seq: true to find req_seq, false to find seq
+ * @devp: Returns pointer to device (there is only one per for each seq).
+ * Set to NULL if none is found
+ * @return 0 if OK, -ve on error
+ */
+int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq,
+ bool find_req_seq, struct udevice **devp);
+
+/**
+ * device_get_child_by_seq() - Get a child device based on a sequence
+ *
+ * If an active device has this sequence it will be returned. If there is no
+ * such device then this will check for a device that is requesting this
+ * sequence.
+ *
+ * The device is probed to activate it ready for use.
+ *
+ * @parent: Parent device
+ * @seq: Sequence number to find (0=first)
+ * @devp: Returns pointer to device (there is only one per for each seq)
+ * Set to NULL if none is found
+ * @return 0 if OK, -ve on error
+ */
+int device_get_child_by_seq(struct udevice *parent, int seq,
+ struct udevice **devp);
+
+/**
+ * device_find_child_by_of_offset() - Find a child device based on FDT offset
+ *
+ * Locates a child device by its device tree offset.
+ *
+ * @parent: Parent device
+ * @of_offset: Device tree offset to find
+ * @devp: Returns pointer to device if found, otherwise this is set to NULL
+ * @return 0 if OK, -ve on error
+ */
+int device_find_child_by_of_offset(struct udevice *parent, int of_offset,
+ struct udevice **devp);
+
+/**
+ * device_get_child_by_of_offset() - Get a child device based on FDT offset
+ *
+ * Locates a child device by its device tree offset.
+ *
+ * The device is probed to activate it ready for use.
+ *
+ * @parent: Parent device
+ * @of_offset: Device tree offset to find
+ * @devp: Returns pointer to device if found, otherwise this is set to NULL
+ * @return 0 if OK, -ve on error
+ */
+int device_get_child_by_of_offset(struct udevice *parent, int of_offset,
+ struct udevice **devp);
+
+/**
+ * device_find_global_by_ofnode() - Get a device based on ofnode
+ *
+ * Locates a device by its device tree ofnode, searching globally throughout
+ * the all driver model devices.
+ *
+ * The device is NOT probed
+ *
+ * @node: Device tree ofnode to find
+ * @devp: Returns pointer to device if found, otherwise this is set to NULL
+ * @return 0 if OK, -ve on error
+ */
+
+int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
+
+/**
+ * device_get_global_by_ofnode() - Get a device based on ofnode
+ *
+ * Locates a device by its device tree ofnode, searching globally throughout
+ * the all driver model devices.
+ *
+ * The device is probed to activate it ready for use.
+ *
+ * @node: Device tree ofnode to find
+ * @devp: Returns pointer to device if found, otherwise this is set to NULL
+ * @return 0 if OK, -ve on error
+ */
+int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
+
+/**
+ * device_find_first_child() - Find the first child of a device
+ *
+ * @parent: Parent device to search
+ * @devp: Returns first child device, or NULL if none
+ * @return 0
+ */
+int device_find_first_child(struct udevice *parent, struct udevice **devp);
+
+/**
+ * device_find_next_child() - Find the next child of a device
+ *
+ * @devp: Pointer to previous child device on entry. Returns pointer to next
+ * child device, or NULL if none
+ * @return 0
+ */
+int device_find_next_child(struct udevice **devp);
+
+/**
+ * device_find_first_inactive_child() - Find the first inactive child
+ *
+ * This is used to locate an existing child of a device which is of a given
+ * uclass.
+ *
+ * The device is NOT probed
+ *
+ * @parent: Parent device to search
+ * @uclass_id: Uclass to look for
+ * @devp: Returns device found, if any
+ * @return 0 if found, else -ENODEV
+ */
+int device_find_first_inactive_child(struct udevice *parent,
+ enum uclass_id uclass_id,
+ struct udevice **devp);
+
+/**
+ * device_find_first_child_by_uclass() - Find the first child of a device in uc
+ *
+ * @parent: Parent device to search
+ * @uclass_id: Uclass to look for
+ * @devp: Returns first child device in that uclass, if any
+ * @return 0 if found, else -ENODEV
+ */
+int device_find_first_child_by_uclass(struct udevice *parent,
+ enum uclass_id uclass_id,
+ struct udevice **devp);
+
+/**
+ * device_find_child_by_name() - Find a child by device name
+ *
+ * @parent: Parent device to search
+ * @name: Name to look for
+ * @devp: Returns device found, if any
+ * @return 0 if found, else -ENODEV
+ */
+int device_find_child_by_name(struct udevice *parent, const char *name,
+ struct udevice **devp);
+
+/**
+ * device_has_children() - check if a device has any children
+ *
+ * @dev: Device to check
+ * @return true if the device has one or more children
+ */
+bool device_has_children(const struct udevice *dev);
+
+/**
+ * device_has_active_children() - check if a device has any active children
+ *
+ * @dev: Device to check
+ * @return true if the device has one or more children and at least one of
+ * them is active (probed).
+ */
+bool device_has_active_children(struct udevice *dev);
+
+/**
+ * device_is_last_sibling() - check if a device is the last sibling
+ *
+ * This function can be useful for display purposes, when special action needs
+ * to be taken when displaying the last sibling. This can happen when a tree
+ * view of devices is being displayed.
+ *
+ * @dev: Device to check
+ * @return true if there are no more siblings after this one - i.e. is it
+ * last in the list.
+ */
+bool device_is_last_sibling(struct udevice *dev);
+
+/**
+ * device_set_name() - set the name of a device
+ *
+ * This must be called in the device's bind() method and no later. Normally
+ * this is unnecessary but for probed devices which don't get a useful name
+ * this function can be helpful.
+ *
+ * The name is allocated and will be freed automatically when the device is
+ * unbound.
+ *
+ * @dev: Device to update
+ * @name: New name (this string is allocated new memory and attached to
+ * the device)
+ * @return 0 if OK, -ENOMEM if there is not enough memory to allocate the
+ * string
+ */
+int device_set_name(struct udevice *dev, const char *name);
+
+/**
+ * device_set_name_alloced() - note that a device name is allocated
+ *
+ * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
+ * unbound the name will be freed. This avoids memory leaks.
+ *
+ * @dev: Device to update
+ */
+void device_set_name_alloced(struct udevice *dev);
+
+/**
+ * device_is_compatible() - check if the device is compatible with the compat
+ *
+ * This allows to check whether the device is comaptible with the compat.
+ *
+ * @dev: udevice pointer for which compatible needs to be verified.
+ * @compat: Compatible string which needs to verified in the given
+ * device
+ * @return true if OK, false if the compatible is not found
+ */
+bool device_is_compatible(struct udevice *dev, const char *compat);
+
+/**
+ * of_machine_is_compatible() - check if the machine is compatible with
+ * the compat
+ *
+ * This allows to check whether the machine is comaptible with the compat.
+ *
+ * @compat: Compatible string which needs to verified
+ * @return true if OK, false if the compatible is not found
+ */
+bool of_machine_is_compatible(const char *compat);
+
+/**
+ * dev_disable_by_path() - Disable a device given its device tree path
+ *
+ * @path: The device tree path identifying the device to be disabled
+ * @return 0 on success, -ve on error
+ */
+int dev_disable_by_path(const char *path);
+
+/**
+ * dev_enable_by_path() - Enable a device given its device tree path
+ *
+ * @path: The device tree path identifying the device to be enabled
+ * @return 0 on success, -ve on error
+ */
+int dev_enable_by_path(const char *path);
+
+/**
+ * device_is_on_pci_bus - Test if a device is on a PCI bus
+ *
+ * @dev: device to test
+ * @return: true if it is on a PCI bus, false otherwise
+ */
+static inline bool device_is_on_pci_bus(struct udevice *dev)
+{
+ return device_get_uclass_id(dev->parent) == UCLASS_PCI;
+}
+
+/**
+ * device_foreach_child_safe() - iterate through child devices safely
+ *
+ * This allows the @pos child to be removed in the loop if required.
+ *
+ * @pos: struct udevice * for the current device
+ * @next: struct udevice * for the next device
+ * @parent: parent device to scan
+ */
+#define device_foreach_child_safe(pos, next, parent) \
+ list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
+
+/**
+ * device_foreach_child() - iterate through child devices
+ *
+ * @pos: struct udevice * for the current device
+ * @parent: parent device to scan
+ */
+#define device_foreach_child(pos, parent) \
+ list_for_each_entry(pos, &parent->child_head, sibling_node)
+
+/**
+ * dm_scan_fdt_dev() - Bind child device in a the device tree
+ *
+ * This handles device which have sub-nodes in the device tree. It scans all
+ * sub-nodes and binds drivers for each node where a driver can be found.
+ *
+ * If this is called prior to relocation, only pre-relocation devices will be
+ * bound (those marked with u-boot,dm-pre-reloc in the device tree, or where
+ * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
+ * be bound.
+ *
+ * @dev: Device to scan
+ * @return 0 if OK, -ve on error
+ */
+int dm_scan_fdt_dev(struct udevice *dev);
+
+/* device resource management */
+typedef void (*dr_release_t)(struct udevice *dev, void *res);
+typedef int (*dr_match_t)(struct udevice *dev, void *res, void *match_data);
+
+#ifdef CONFIG_DEVRES
+
+#ifdef CONFIG_DEBUG_DEVRES
+void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
+ const char *name);
+#define _devres_alloc(release, size, gfp) \
+ __devres_alloc(release, size, gfp, #release)
+#else
+void *_devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
+#endif
+
+/**
+ * devres_alloc() - Allocate device resource data
+ * @release: Release function devres will be associated with
+ * @size: Allocation size
+ * @gfp: Allocation flags
+ *
+ * Allocate devres of @size bytes. The allocated area is associated
+ * with @release. The returned pointer can be passed to
+ * other devres_*() functions.
+ *
+ * RETURNS:
+ * Pointer to allocated devres on success, NULL on failure.
+ */
+#define devres_alloc(release, size, gfp) \
+ _devres_alloc(release, size, gfp | __GFP_ZERO)
+
+/**
+ * devres_free() - Free device resource data
+ * @res: Pointer to devres data to free
+ *
+ * Free devres created with devres_alloc().
+ */
+void devres_free(void *res);
+
+/**
+ * devres_add() - Register device resource
+ * @dev: Device to add resource to
+ * @res: Resource to register
+ *
+ * Register devres @res to @dev. @res should have been allocated
+ * using devres_alloc(). On driver detach, the associated release
+ * function will be invoked and devres will be freed automatically.
+ */
+void devres_add(struct udevice *dev, void *res);
+
+/**
+ * devres_find() - Find device resource
+ * @dev: Device to lookup resource from
+ * @release: Look for resources associated with this release function
+ * @match: Match function (optional)
+ * @match_data: Data for the match function
+ *
+ * Find the latest devres of @dev which is associated with @release
+ * and for which @match returns 1. If @match is NULL, it's considered
+ * to match all.
+ *
+ * @return pointer to found devres, NULL if not found.
+ */
+void *devres_find(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data);
+
+/**
+ * devres_get() - Find devres, if non-existent, add one atomically
+ * @dev: Device to lookup or add devres for
+ * @new_res: Pointer to new initialized devres to add if not found
+ * @match: Match function (optional)
+ * @match_data: Data for the match function
+ *
+ * Find the latest devres of @dev which has the same release function
+ * as @new_res and for which @match return 1. If found, @new_res is
+ * freed; otherwise, @new_res is added atomically.
+ *
+ * @return ointer to found or added devres.
+ */
+void *devres_get(struct udevice *dev, void *new_res,
+ dr_match_t match, void *match_data);
+
+/**
+ * devres_remove() - Find a device resource and remove it
+ * @dev: Device to find resource from
+ * @release: Look for resources associated with this release function
+ * @match: Match function (optional)
+ * @match_data: Data for the match function
+ *
+ * Find the latest devres of @dev associated with @release and for
+ * which @match returns 1. If @match is NULL, it's considered to
+ * match all. If found, the resource is removed atomically and
+ * returned.
+ *
+ * @return ointer to removed devres on success, NULL if not found.
+ */
+void *devres_remove(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data);
+
+/**
+ * devres_destroy() - Find a device resource and destroy it
+ * @dev: Device to find resource from
+ * @release: Look for resources associated with this release function
+ * @match: Match function (optional)
+ * @match_data: Data for the match function
+ *
+ * Find the latest devres of @dev associated with @release and for
+ * which @match returns 1. If @match is NULL, it's considered to
+ * match all. If found, the resource is removed atomically and freed.
+ *
+ * Note that the release function for the resource will not be called,
+ * only the devres-allocated data will be freed. The caller becomes
+ * responsible for freeing any other data.
+ *
+ * @return 0 if devres is found and freed, -ENOENT if not found.
+ */
+int devres_destroy(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data);
+
+/**
+ * devres_release() - Find a device resource and destroy it, calling release
+ * @dev: Device to find resource from
+ * @release: Look for resources associated with this release function
+ * @match: Match function (optional)
+ * @match_data: Data for the match function
+ *
+ * Find the latest devres of @dev associated with @release and for
+ * which @match returns 1. If @match is NULL, it's considered to
+ * match all. If found, the resource is removed atomically, the
+ * release function called and the resource freed.
+ *
+ * @return 0 if devres is found and freed, -ENOENT if not found.
+ */
+int devres_release(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data);
+
+/* managed devm_k.alloc/kfree for device drivers */
+/**
+ * devm_kmalloc() - Resource-managed kmalloc
+ * @dev: Device to allocate memory for
+ * @size: Allocation size
+ * @gfp: Allocation gfp flags
+ *
+ * Managed kmalloc. Memory allocated with this function is
+ * automatically freed on driver detach. Like all other devres
+ * resources, guaranteed alignment is unsigned long long.
+ *
+ * @return pointer to allocated memory on success, NULL on failure.
+ */
+void *devm_kmalloc(struct udevice *dev, size_t size, gfp_t gfp);
+static inline void *devm_kzalloc(struct udevice *dev, size_t size, gfp_t gfp)
+{
+ return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
+}
+static inline void *devm_kmalloc_array(struct udevice *dev,
+ size_t n, size_t size, gfp_t flags)
+{
+ if (size != 0 && n > SIZE_MAX / size)
+ return NULL;
+ return devm_kmalloc(dev, n * size, flags);
+}
+static inline void *devm_kcalloc(struct udevice *dev,
+ size_t n, size_t size, gfp_t flags)
+{
+ return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
+}
+
+/**
+ * devm_kfree() - Resource-managed kfree
+ * @dev: Device this memory belongs to
+ * @ptr: Memory to free
+ *
+ * Free memory allocated with devm_kmalloc().
+ */
+void devm_kfree(struct udevice *dev, void *ptr);
+
+#else /* ! CONFIG_DEVRES */
+
+static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
+{
+ return kzalloc(size, gfp);
+}
+
+static inline void devres_free(void *res)
+{
+ kfree(res);
+}
+
+static inline void devres_add(struct udevice *dev, void *res)
+{
+}
+
+static inline void *devres_find(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data)
+{
+ return NULL;
+}
+
+static inline void *devres_get(struct udevice *dev, void *new_res,
+ dr_match_t match, void *match_data)
+{
+ return NULL;
+}
+
+static inline void *devres_remove(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data)
+{
+ return NULL;
+}
+
+static inline int devres_destroy(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data)
+{
+ return 0;
+}
+
+static inline int devres_release(struct udevice *dev, dr_release_t release,
+ dr_match_t match, void *match_data)
+{
+ return 0;
+}
+
+static inline void *devm_kmalloc(struct udevice *dev, size_t size, gfp_t gfp)
+{
+ return kmalloc(size, gfp);
+}
+
+static inline void *devm_kzalloc(struct udevice *dev, size_t size, gfp_t gfp)
+{
+ return kzalloc(size, gfp);
+}
+
+static inline void *devm_kmalloc_array(struct udevice *dev,
+ size_t n, size_t size, gfp_t flags)
+{
+ /* TODO: add kmalloc_array() to linux/compat.h */
+ if (size != 0 && n > SIZE_MAX / size)
+ return NULL;
+ return kmalloc(n * size, flags);
+}
+
+static inline void *devm_kcalloc(struct udevice *dev,
+ size_t n, size_t size, gfp_t flags)
+{
+ /* TODO: add kcalloc() to linux/compat.h */
+ return kmalloc(n * size, flags | __GFP_ZERO);
+}
+
+static inline void devm_kfree(struct udevice *dev, void *ptr)
+{
+ kfree(ptr);
+}
+
+#endif /* ! CONFIG_DEVRES */
+
+/*
+ * REVISIT:
+ * remove the following after resolving conflicts with <linux/compat.h>
+ */
+#ifdef dev_dbg
+#undef dev_dbg
+#endif
+#ifdef dev_vdbg
+#undef dev_vdbg
+#endif
+#ifdef dev_info
+#undef dev_info
+#endif
+#ifdef dev_err
+#undef dev_err
+#endif
+#ifdef dev_warn
+#undef dev_warn
+#endif
+
+/*
+ * REVISIT:
+ * print device name like Linux
+ */
+#define dev_printk(dev, fmt, ...) \
+({ \
+ printk(fmt, ##__VA_ARGS__); \
+})
+
+#define __dev_printk(level, dev, fmt, ...) \
+({ \
+ if (level < CONFIG_VAL(LOGLEVEL)) \
+ dev_printk(dev, fmt, ##__VA_ARGS__); \
+})
+
+#define dev_emerg(dev, fmt, ...) \
+ __dev_printk(0, dev, fmt, ##__VA_ARGS__)
+#define dev_alert(dev, fmt, ...) \
+ __dev_printk(1, dev, fmt, ##__VA_ARGS__)
+#define dev_crit(dev, fmt, ...) \
+ __dev_printk(2, dev, fmt, ##__VA_ARGS__)
+#define dev_err(dev, fmt, ...) \
+ __dev_printk(3, dev, fmt, ##__VA_ARGS__)
+#define dev_warn(dev, fmt, ...) \
+ __dev_printk(4, dev, fmt, ##__VA_ARGS__)
+#define dev_notice(dev, fmt, ...) \
+ __dev_printk(5, dev, fmt, ##__VA_ARGS__)
+#define dev_info(dev, fmt, ...) \
+ __dev_printk(6, dev, fmt, ##__VA_ARGS__)
+
+#ifdef DEBUG
+#define dev_dbg(dev, fmt, ...) \
+ __dev_printk(7, dev, fmt, ##__VA_ARGS__)
+#else
+#define dev_dbg(dev, fmt, ...) \
+({ \
+ if (0) \
+ __dev_printk(7, dev, fmt, ##__VA_ARGS__); \
+})
+#endif
+
+#ifdef VERBOSE_DEBUG
+#define dev_vdbg dev_dbg
+#else
+#define dev_vdbg(dev, fmt, ...) \
+({ \
+ if (0) \
+ __dev_printk(7, dev, fmt, ##__VA_ARGS__); \
+})
+#endif
+
+#endif