DTS详解
Zephyr

/dts-v1/
/{
    a-node{
        a_node_label: a-sub-node {
            foo = <3>;
        };
        b-sub-node {
            foo = <3>;
            bar = <&a_node_label>;
        };
    };
};

#有address
sram0: memory@3ffb0000 {
    compatible = "mmio-sram";
    reg = < 0x3ffb0000 0x2c200 >;
};
#无address
button0: button_0 {
    gpios = < &gpio0 0x0 0x11 >;
    label = "BOOT Button";
    zephyr,code = < 0xb >;
};

/dts-v1/;
/ {
    chosen {
        zephyr,console = &uart0;
    };
    aliases {
        my-uart = &uart0;
    };
    soc {
        uart0: serial@12340000 {
            ...
        };
    };
};

#include <zephyr/dt-bindings/display/ili9xxx.h>
ili9342c: ili9342c@0 {
    compatible = "ilitek,ili9342c";
    mipi-max-frequency = <30000000>;
    reg = <0>;
    vin-supply = <&lcd_bg>;
    pixel-format = <ILI9XXX_PIXEL_FORMAT_RGB565>;
    display-inversion;
    width = <320>;
    height = <240>;
    rotation = <0>;
};

soc {
    #address-cells = < 0x1 >;
    #size-cells = < 0x1 >;
    compatible = "simple-bus";
    interrupt-parent = < &nvic >;
    ranges;
    i3c0: i3c@36000 {
        compatible = "nxp,mcux-i3c";
        reg = < 0x36000 0x1000 >;
        interrupts = < 0x31 0x0 >;
        clocks = < &clkctl1 0x600 >;
        clk-divider = < 0xc >;
        clk-divider-slow = < 0x1 >;
        clk-divider-tc = < 0x1 >;
        status = "okay";
        #address-cells = < 0x3 >;
        #size-cells = < 0x0 >;
        pinctrl-0 = < &pinmux_i3c >;
        pinctrl-names = "default";
        i2c-scl-hz = < 0x61a80 >;
        i3c-scl-hz = < 0x61a80 >;
        i3c-od-scl-hz = < 0x61a80 >;
        lps22hh0: lps22hh@5d0000020800b30000 {
            compatible = "st,lps22hh";
            reg = < 0x5d 0x208 0xb30000 >;
            status = "okay";
        };
    };
}

soc {
    #address-cells = < 0x1 >;
    #size-cells = < 0x1 >;
    compatible = "simple-bus";
    pcc: clock-controller@4000d000 {
        compatible = "nuvoton,npcx-pcc";
        /* Cells for bus type, clock control reg and bit */
        #clock-cells = <3>;
        /* First reg region is Power Management Controller */
        /* Second reg region is Core Domain Clock Generator */
        reg = <0x4000d000 0x2000 0x400b5000 0x2000>;
        reg-names = "pmc", "cdcg";
    };
}

peripheral: peripheral@50000000 {
    ranges = < 0x0 0x50000000 0x10000000 >;
    #address-cells = < 0x1 >;
    #size-cells = < 0x1 >;
    clkctl0: clkctl@1000 {
        compatible = "nxp,lpc-syscon";
        reg = < 0x1000 0x1000 >;
        #clock-cells = < 0x1 >;
    };
};

chosen {
    zephyr,sram = &sram0;
    zephyr,console = &uart0;
    zephyr,shell-uart = &uart0;
    zephyr,flash = &flash0;
    zephyr,code-partition = &slot0_partition;
    zephyr,bt-hci = &esp32_bt_hci;
};

chosen {
    zephyr,sram = &sram0;
    zephyr,console = &uart0;
    zephyr,shell-uart = &uart1;
    zephyr,flash = &flash0;
    zephyr,code-partition = &slot0_partition;
    zephyr,bt-hci = &esp32_bt_hci;
};

aliases {
    sw0 = &user_button1;
    i2c-0 = &i2c0;
    watchdog0 = &wdt0;
};

/* Returns the operations for a device */
#define device_get_ops(dev) ((dev)->driver->ops)

u32 dev_get_flags(const struct udevice *dev);
void dev_or_flags(const struct udevice *dev, u32 or);
void dev_bic_flags(const struct udevice *dev, u32 bic);

static inline __attribute_const__ ofnode dev_ofnode(const struct udevice *dev)

#define device_active(dev)  (dev_get_flags(dev) & DM_FLAG_ACTIVATED)

#define dev_set_dma_offset(_dev, _offset)   _dev->dma_offset = _offset
#define dev_get_dma_offset(_dev)        _dev->dma_offset

int dev_of_offset(const struct udevice *dev)
/** 
 * @brief 检查node是否存在
 * @param dev 
 */
bool dev_has_ofnode(const struct udevice *dev)
void dev_set_ofnode(struct udevice *dev, ofnode node)
int dev_seq(const struct udevice *dev)

/**
 * dev_get_plat() - 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_plat(const struct udevice *dev);

/**
 * dev_get_parent_plat() - 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_plat(const struct udevice *dev);

/**
 * dev_get_uclass_plat() - 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_plat(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);

/**
 * dev_get_attach_ptr() - Get the value of an attached pointed tag
 *
 * The tag is assumed to hold a pointer, if it exists
 *
 * @dev: Device to look at
 * @tag: Tag to access
 * @return value of tag, or NULL if there is no tag of this type
 */
void *dev_get_attach_ptr(const struct udevice *dev, enum dm_tag_t tag);

/**
 * dev_get_attach_size() - Get the size of an attached tag
 *
 * Core tags have an automatic-allocation mechanism where the allocated size is
 * defined by the device, parent or uclass. This returns the size associated
 * with a particular tag
 *
 * @dev: Device to look at
 * @tag: Tag to access
 * @return size of auto-allocated data, 0 if none
 */
int dev_get_attach_size(const struct udevice *dev, enum dm_tag_t tag);

/**
 * 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.
 *
 * @parent: 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(const struct udevice *parent, int index,
                     struct udevice **devp);

/**
 * device_get_child_count() - Get the child count of a device
 *
 * Returns the number of children to a device.
 *
 * @parent: Parent device to check
 */
int device_get_child_count(const struct udevice *parent);

/**
 * device_get_decendent_count() - Get the total number of decendents of a device
 *
 * Returns the total number of decendents, including all children
 *
 * @parent: Parent device to check
 */
int device_get_decendent_count(const 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.
 *
 * @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, -ENODEV if not found
 */
int device_find_child_by_seq(const struct udevice *parent, int 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(const 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(const 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(const 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_get_by_ofplat_idx() - Get a device based on of-platdata index
 *
 * Locates a device by either its struct driver_info index, or its
 * struct udevice index. The latter is used with OF_PLATDATA_INST, since we have
 * a list of build-time instantiated struct udevice records, The former is used
 * with !OF_PLATDATA_INST since in that case we have a list of
 * struct driver_info records.
 *
 * The index number is written into the idx field of struct phandle_1_arg, etc.
 * It is the position of this driver_info/udevice in its linker list.
 *
 * The device is probed to activate it ready for use.
 *
 * @idx: Index number of the driver_info/udevice structure (0=first)
 * @devp: Returns pointer to device if found, otherwise this is set to NULL
 * Return: 0 if OK, -ve on error
 */
int device_get_by_ofplat_idx(uint idx, 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(const 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, else NULL
 * Return: 0 if found, else -ENODEV
 */
int device_find_first_inactive_child(const 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, else NULL
 * Return: 0 if found, else -ENODEV
 */
int device_find_first_child_by_uclass(const struct udevice *parent,
                                      enum uclass_id uclass_id,
                                      struct udevice **devp);

/**
 * device_find_child_by_namelen() - Find a child by device name
 *
 * @parent: Parent device to search
 * @name:   Name to look for
 * @len:    Length of the name
 * @devp:   Returns device found, if any
 * Return: 0 if found, else -ENODEV
 */
int device_find_child_by_namelen(const struct udevice *parent, const char *name,
                                 int len, 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(const struct udevice *parent, const char *name,
                              struct udevice **devp);

/**
 * device_first_child_ofdata_err() - Find the first child and reads its plat
 *
 * The of_to_plat() method is called on the child before it is returned,
 * but the child is not probed.
 *
 * @parent: Parent to check
 * @devp: Returns child that was found, if any
 * Return: 0 on success, -ENODEV if no children, other -ve on error
 */
int device_first_child_ofdata_err(struct udevice *parent,
                                  struct udevice **devp);

/*
 * device_next_child_ofdata_err() - Find the next child and read its plat
 *
 * The of_to_plat() method is called on the child before it is returned,
 * but the child is not probed.
 *
 * @devp: On entry, points to the previous child; on exit returns the child that
 *  was found, if any
 * Return: 0 on success, -ENODEV if no children, other -ve on error
 */
int device_next_child_ofdata_err(struct udevice **devp);

/**
 * device_first_child_err() - Get the first child of a device
 *
 * The device returned is probed if necessary, and ready for use
 *
 * @parent: Parent device to search
 * @devp:   Returns device found, if any
 * Return: 0 if found, -ENODEV if not, -ve error if device failed to probe
 */
int device_first_child_err(struct udevice *parent, struct udevice **devp);

/**
 * device_next_child_err() - Get the next child of a parent device
 *
 * The device returned is probed if necessary, and ready for use
 *
 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
 * to the next sibling if no error occurred
 * Return: 0 if found, -ENODEV if not, -ve error if device failed to probe
 */
int device_next_child_err(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(const 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(const 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(const 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(const struct udevice *dev)
{
        return dev->parent && 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)

/**
 * device_foreach_child_of_to_plat() - iterate through children
 *
 * This stops when it gets an error, with @pos set to the device that failed to
 * read ofdata.
 *
 * This creates a for() loop which works through the available children of
 * a device in order from start to end. Device ofdata is read by calling
 * device_of_to_plat() on each one. The devices are not probed.
 *
 * @pos: struct udevice * for the current device
 * @parent: parent device to scan
 */
#define device_foreach_child_of_to_plat(pos, parent)    \
        for (int _ret = device_first_child_ofdata_err(parent, &pos); !_ret; \
             _ret = device_next_child_ofdata_err(&pos))

/**
 * device_foreach_child_probe() - iterate through children, probing them
 *
 * This creates a for() loop which works through the available children of
 * a device in order from start to end. Devices are probed if necessary,
 * and ready for use.
 *
 * This stops when it gets an error, with @pos set to the device that failed to
 * probe
 *
 * @pos: struct udevice * for the current device
 * @parent: parent device to scan
 */
#define device_foreach_child_probe(pos, parent) \
        for (int _ret = device_first_child_err(parent, &pos); !_ret; \
             _ret = device_next_child_err(&pos))

/**
 * dm_scan_fdt_dev() - Bind child device in 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 bootph-all 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);

/**
 * oftree_reset() - reset the state of the oftree list
 *
 * Reset the oftree list so it can be started again. This should be called
 * once the control FDT is in place, but before the ofnode interface is used.
 */
void oftree_reset(void);

/**
 * ofnode_to_fdt() - convert an ofnode to a flat DT pointer
 *
 * This cannot be called if the reference contains a node pointer.
 *
 * @node: Reference containing offset (possibly invalid)
 * Return: DT offset (can be NULL)
 */
void *ofnode_to_fdt(ofnode node);

/**
 * ofnode_to_offset() - convert an ofnode to a flat DT offset
 *
 * This cannot be called if the reference contains a node pointer.
 *
 * @node: Reference containing offset (possibly invalid)
 * Return: DT offset (can be -1)
 */
int ofnode_to_offset(ofnode node);

/**
 * oftree_from_fdt() - Returns an oftree from a flat device tree pointer
 *
 * If @fdt is not already registered in the list of current device trees, it is
 * added to the list.
 *
 * @fdt: Device tree to use
 *
 * Returns: reference to the given node
 */
oftree oftree_from_fdt(void *fdt);

/**
 * noffset_to_ofnode() - convert a DT offset to an ofnode
 *
 * @other_node: Node in the same tree to use as a reference
 * @of_offset: DT offset (either valid, or -1)
 * Return: reference to the associated DT offset
 */
ofnode noffset_to_ofnode(ofnode other_node, int of_offset);

/**
 * ofnode_to_np() - convert an ofnode to a live DT node pointer
 *
 * This cannot be called if the reference contains an offset.
 *
 * @node: Reference containing struct device_node * (possibly invalid)
 * Return: pointer to device node (can be NULL)
 */
static inline struct device_node *ofnode_to_np(ofnode node)

/**
 * ofnode_valid() - check if an ofnode is valid
 *
 * @node: Reference containing offset (possibly invalid)
 * Return: true if the reference contains a valid ofnode, false if not
 */
static inline bool ofnode_valid(ofnode node)

/**
 * oftree_lookup_fdt() - obtain the FDT pointer from an oftree
 *
 * This can only be called when flat tree is enabled
 *
 * @tree: Tree to look at
 * @return FDT pointer from the tree
 */
static inline void *oftree_lookup_fdt(oftree tree)
/**
 * offset_to_ofnode() - convert a DT offset to an ofnode
 *
 * @of_offset: DT offset (either valid, or -1)
 * Return: reference to the associated DT offset
 */
static inline ofnode offset_to_ofnode(int of_offset)
/**
 * np_to_ofnode() - convert a node pointer to an ofnode
 *
 * @np: Live node pointer (can be NULL)
 * Return: reference to the associated node pointer
 */
static inline ofnode np_to_ofnode(struct device_node *np)
/**
 * ofnode_is_np() - check if a reference is a node pointer
 *
 * This function associated that if there is a valid live tree then all
 * references will use it. This is because using the flat DT when the live tree
 * is valid is not permitted.
 *
 * @node: reference to check (possibly invalid)
 * Return: true if the reference is a live node pointer, false if it is a DT
 * offset
 */
static inline bool ofnode_is_np(ofnode node)
/**
 * ofnode_equal() - check if two references are equal
 *
 * @ref1: first reference to check (possibly invalid)
 * @ref2: second reference to check (possibly invalid)
 * Return: true if equal, else false
 */
static inline bool ofnode_equal(ofnode ref1, ofnode ref2)
/**
 * oftree_valid() - check if an oftree is valid
 *
 * @tree: Reference containing oftree
 * Return: true if the reference contains a valid oftree, false if node
 */
static inline bool oftree_valid(oftree tree)
/**
 * oftree_null() - Obtain a null oftree
 *
 * This returns an oftree which points to no tree. It works both with the flat
 * tree and livetree.
 */
static inline oftree oftree_null(void)
/**
 * ofnode_null() - Obtain a null ofnode
 *
 * This returns an ofnode which points to no node. It works both with the flat
 * tree and livetree.
 */
static inline ofnode ofnode_null(void)
static inline ofnode ofnode_root(void)
/**
 * ofprop_valid() - check if an ofprop is valid
 *
 * @prop: Pointer to ofprop to check
 * Return: true if the reference contains a valid ofprop, false if not
 */
static inline bool ofprop_valid(struct ofprop *prop)
/**
 * oftree_default() - Returns the default device tree (U-Boot's control FDT)
 *
 * Returns: reference to the control FDT
 */
static inline oftree oftree_default(void)
/**
 * oftree_from_np() - Returns an oftree from a node pointer
 *
 * @root: Root node of the tree
 * Returns: reference to the given node
 */
static inline oftree oftree_from_np(struct device_node *root)
/**
 * ofnode_name_eq() - Check if the node name is equivalent to a given name
 *                    ignoring the unit address
 *
 * @node:   valid node reference that has to be compared
 * @name:   name that has to be compared with the node name
 * Return: true if matches, false if it doesn't match
 */
bool ofnode_name_eq(ofnode node, const char *name);

/**
 * ofnode_read_u8() - Read a 8-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @outp:   place to put value (if found)
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_u8(ofnode node, const char *propname, u8 *outp);

/**
 * ofnode_read_u8_default() - Read a 8-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @def:    default value to return if the property has no value
 * Return: property value, or @def if not found
 */
u8 ofnode_read_u8_default(ofnode node, const char *propname, u8 def);

/**
 * ofnode_read_u16() - Read a 16-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @outp:   place to put value (if found)
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_u16(ofnode node, const char *propname, u16 *outp);

/**
 * ofnode_read_u16_default() - Read a 16-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @def:    default value to return if the property has no value
 * Return: property value, or @def if not found
 */
u16 ofnode_read_u16_default(ofnode node, const char *propname, u16 def);

/**
 * ofnode_read_u32() - Read a 32-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @outp:   place to put value (if found)
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_u32(ofnode node, const char *propname, u32 *outp);

/**
 * ofnode_read_u32_index() - Read a 32-bit integer from a multi-value property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @index:  index of the integer to return
 * @outp:   place to put value (if found)
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_u32_index(ofnode node, const char *propname, int index,
                          u32 *outp);

/**
 * ofnode_read_s32() - Read a 32-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @outp:   place to put value (if found)
 * Return: 0 if OK, -ve on error
 */
static inline int ofnode_read_s32(ofnode node, const char *propname,s32 *outp)
/**
 * ofnode_read_u32_default() - Read a 32-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @def:    default value to return if the property has no value
 * Return: property value, or @def if not found
 */
u32 ofnode_read_u32_default(ofnode node, const char *propname, u32 def);

/**
 * ofnode_read_u32_index_default() - Read a 32-bit integer from a multi-value
 *                                   property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @index:  index of the integer to return
 * @def:    default value to return if the property has no value
 * Return: property value, or @def if not found
 */
u32 ofnode_read_u32_index_default(ofnode node, const char *propname, int index,u32 def);

/**
 * ofnode_read_s32_default() - Read a 32-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @def:    default value to return if the property has no value
 * Return: property value, or @def if not found
 */
int ofnode_read_s32_default(ofnode node, const char *propname, s32 def);

/**
 * ofnode_read_u64() - Read a 64-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @outp:   place to put value (if found)
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_u64(ofnode node, const char *propname, u64 *outp);

/**
 * ofnode_read_u64_default() - Read a 64-bit integer from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read from
 * @def:    default value to return if the property has no value
 * Return: property value, or @def if not found
 */
u64 ofnode_read_u64_default(ofnode node, const char *propname, u64 def);

/**
 * ofnode_read_prop() - Read a property from a node
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read
 * @sizep:  if non-NULL, returns the size of the property, or an error code
 *              if not found
 * Return: property value, or NULL if there is no such property
 */
const void *ofnode_read_prop(ofnode node, const char *propname, int *sizep);

/**
 * ofnode_read_string() - Read a string from a property
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read
 * Return: string from property value, or NULL if there is no such property
 */
const char *ofnode_read_string(ofnode node, const char *propname);

/**
 * ofnode_read_u32_array() - Find and read an array of 32 bit integers
 *
 * @node:   valid node reference to read property from
 * @propname:   name of the property to read
 * @out_values: pointer to return value, modified only if return value is 0
 * @sz:     number of array elements to read
 * Return: 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
 *
 * Search for a property in a device node and read 32-bit value(s) from
 * it.
 *
 * The out_values is modified only if a valid u32 value can be decoded.
 */
int ofnode_read_u32_array(ofnode node, const char *propname,u32 *out_values, size_t sz);

/**
 * ofnode_read_bool() - read a boolean value from a property
 * 读取node下的属性propname，如果有返回true，否则false
 * 如ofnode_read_bool(node, "gpio-controller")
 * @node:   valid node reference to read property from
 * @propname:   name of property to read
 * Return: true if property is present (meaning true), false if not present
 */
bool ofnode_read_bool(ofnode node, const char *propname);
/**
 * ofnode_find_subnode() - find a named subnode of a parent node
 *
 * @node:   valid reference to parent node
 * @subnode_name: name of subnode to find
 * Return: reference to subnode (which can be invalid if there is no such
 * subnode)
 */
ofnode ofnode_find_subnode(ofnode node, const char *subnode_name);
/**
 * ofnode_is_enabled() - Checks whether a node is enabled.
 * This looks for a 'status' property. If this exists, then returns true if
 * the status is 'okay' and false otherwise. If there is no status property,
 * it returns true on the assumption that anything mentioned should be enabled
 * by default.
 *
 * @node: node to examine
 * Return: false (not enabled) or true (enabled)
 */
bool ofnode_is_enabled(ofnode node);

/**
 * ofnode_first_subnode() - find the first subnode of a parent node
 *
 * @node:   valid reference to a valid parent node
 * Return: reference to the first subnode (which can be invalid if the parent
 * node has no subnodes)
 */
ofnode ofnode_first_subnode(ofnode node);

/**
 * ofnode_next_subnode() - find the next sibling of a subnode
 *
 * @node:   valid reference to previous node (sibling)
 * Return: reference to the next subnode (which can be invalid if the node
 * has no more siblings)
 */
ofnode ofnode_next_subnode(ofnode node);

/**
 * ofnode_get_parent() - get the ofnode's parent (enclosing ofnode)
 *
 * @node: valid node to look up
 * Return: ofnode reference of the parent node
 */
ofnode ofnode_get_parent(ofnode node);

/**
 * ofnode_get_name() - get the name of a node
 * 读取node名字，不是读取flag的名字
 * @node: valid node to look up
 * Return: name of node (for the root node this is "")
 */
const char *ofnode_get_name(ofnode node);

/**
 * ofnode_get_path() - get the full path of a node
 *
 * @node: valid node to look up
 * @buf: buffer to write the node path into
 * @buflen: buffer size
 * Return: 0 if OK, -ve on error
 */
int ofnode_get_path(ofnode node, char *buf, int buflen);

/**
 * ofnode_get_by_phandle() - get ofnode from phandle
 *
 * This uses the default (control) device tree
 *
 * @phandle:    phandle to look up
 * Return: ofnode reference to the phandle
 */
ofnode ofnode_get_by_phandle(uint phandle);

/**
 * oftree_get_by_phandle() - get ofnode from phandle
 *
 * @tree:   tree to use
 * @phandle:    phandle to look up
 * Return: ofnode reference to the phandle
 */
ofnode oftree_get_by_phandle(oftree tree, uint phandle);

/**
 * ofnode_read_size() - read the size of a property
 *
 * @node: node to check
 * @propname: property to check
 * Return: size of property if present, or -EINVAL if not
 */
int ofnode_read_size(ofnode node, const char *propname);

/**
 * ofnode_get_addr_size_index() - get an address/size from a node
 *                based on index
 *
 * This reads the register address/size from a node based on index
 *
 * @node: node to read from
 * @index: Index of address to read (0 for first)
 * @size: Pointer to size of the address
 * Return: address, or FDT_ADDR_T_NONE if not present or invalid
 */
fdt_addr_t ofnode_get_addr_size_index(ofnode node, int index,
                                      fdt_size_t *size);

/**
 * ofnode_get_addr_size_index_notrans() - get an address/size from a node
 *                    based on index, without address
 *                    translation
 *
 * This reads the register address/size from a node based on index.
 * The resulting address is not translated. Useful for example for on-disk
 * addresses.
 *
 * @node: node to read from
 * @index: Index of address to read (0 for first)
 * @size: Pointer to size of the address
 * Return: address, or FDT_ADDR_T_NONE if not present or invalid
 */
fdt_addr_t ofnode_get_addr_size_index_notrans(ofnode node, int index,
                                              fdt_size_t *size);

/**
 * ofnode_get_addr_index() - get an address from a node
 *
 * This reads the register address from a node
 *
 * @node: node to read from
 * @index: Index of address to read (0 for first)
 * Return: address, or FDT_ADDR_T_NONE if not present or invalid
 */
fdt_addr_t ofnode_get_addr_index(ofnode node, int index);

/**
 * ofnode_get_addr() - get an address from a node
 *
 * This reads the register address from a node
 *
 * @node: node to read from
 * Return: address, or FDT_ADDR_T_NONE if not present or invalid
 */
fdt_addr_t ofnode_get_addr(ofnode node);

/**
 * ofnode_get_size() - get size from a node
 *
 * This reads the register size from a node
 *
 * @node: node to read from
 * Return: size of the address, or FDT_SIZE_T_NONE if not present or invalid
 */
fdt_size_t ofnode_get_size(ofnode node);

/**
 * ofnode_stringlist_search() - find a string in a string list and return index
 *
 * Note that it is possible for this function to succeed on property values
 * that are not NUL-terminated. That's because the function will stop after
 * finding the first occurrence of @string. This can for example happen with
 * small-valued cell properties, such as #address-cells, when searching for
 * the empty string.
 *
 * @node: node to check
 * @propname: name of the property containing the string list
 * @string: string to look up in the string list
 *
 * Return:
 *   the index of the string in the list of strings
 *   -ENODATA if the property is not found
 *   -EINVAL on some other error
 */
int ofnode_stringlist_search(ofnode node, const char *propname,
                             const char *string);

/**
 * ofnode_read_string_index() - obtain an indexed string from a string list
 *
 * Note that this will successfully extract strings from properties with
 * non-NUL-terminated values. For example on small-valued cell properties
 * this function will return the empty string.
 *
 * If non-NULL, the length of the string (on success) or a negative error-code
 * (on failure) will be stored in the integer pointer to by lenp.
 *
 * @node: node to check
 * @propname: name of the property containing the string list
 * @index: index of the string to return (cannot be negative)
 * @outp: return location for the string
 *
 * Return:
 *   0 if found or -ve error value if not found
 */
int ofnode_read_string_index(ofnode node, const char *propname, int index,
                             const char **outp);

/**
 * ofnode_read_string_count() - find the number of strings in a string list
 *
 * @node: node to check
 * @property: name of the property containing the string list
 * Return:
 *   number of strings in the list, or -ve error value if not found
 */
int ofnode_read_string_count(ofnode node, const char *property);

/**
 * ofnode_read_string_list() - read a list of strings
 *
 * This produces a list of string pointers with each one pointing to a string
 * in the string list. If the property does not exist, it returns {NULL}.
 *
 * The data is allocated and the caller is reponsible for freeing the return
 * value (the list of string pointers). The strings themselves may not be
 * changed as they point directly into the devicetree property.
 *
 * @node: node to check
 * @property: name of the property containing the string list
 * @listp: returns an allocated, NULL-terminated list of strings if the return
 *  value is > 0, else is set to NULL
 * Return:
 * number of strings in list, 0 if none, -ENOMEM if out of memory,
 * -EINVAL if no such property, -EENODATA if property is empty
 */
int ofnode_read_string_list(ofnode node, const char *property,
                            const char ***listp);

/**
 * ofnode_parse_phandle_with_args() - Find a node pointed by phandle in a list
 *
 * This function is useful to parse lists of phandles and their arguments.
 * Returns 0 on success and fills out_args, on error returns appropriate
 * errno value.
 *
 * Caller is responsible to call of_node_put() on the returned out_args->np
 * pointer.
 *
 * Example:
 *
 * .. code-block::
 *
 *   phandle1: node1 {
 *       #list-cells = <2>;
 *   };
 *   phandle2: node2 {
 *       #list-cells = <1>;
 *   };
 *   node3 {
 *       list = <&phandle1 1 2 &phandle2 3>;
 *   };
 *
 * To get a device_node of the `node2' node you may call this:
 * ofnode_parse_phandle_with_args(node3, "list", "#list-cells", 0, 1, &args);
 *
 * @node:   device tree node containing a list
 * @list_name:  property name that contains a list
 * @cells_name: property name that specifies phandles' arguments count
 * @cell_count: Cell count to use if @cells_name is NULL
 * @index:  index of a phandle to parse out
 * @out_args:   optional pointer to output arguments structure (will be filled)
 * Return:
 *   0 on success (with @out_args filled out if not NULL), -ENOENT if
 *   @list_name does not exist, -EINVAL if a phandle was not found,
 *   @cells_name could not be found, the arguments were truncated or there
 *   were too many arguments.
 */
int ofnode_parse_phandle_with_args(ofnode node, const char *list_name,
                                   const char *cells_name, int cell_count,
                                   int index,
                                   struct ofnode_phandle_args *out_args);

/**
 * ofnode_count_phandle_with_args() - Count number of phandle in a list
 *
 * This function is useful to count phandles into a list.
 * Returns number of phandle on success, on error returns appropriate
 * errno value.
 *
 * @node:   device tree node containing a list
 * @list_name:  property name that contains a list
 * @cells_name: property name that specifies phandles' arguments count
 * @cell_count: Cell count to use if @cells_name is NULL
 * Return:
 *   number of phandle on success, -ENOENT if @list_name does not exist,
 *   -EINVAL if a phandle was not found, @cells_name could not be found.
 */
int ofnode_count_phandle_with_args(ofnode node, const char *list_name,
                                   const char *cells_name, int cell_count);

/**
 * ofnode_path() - find a node by full path
 *
 * This uses the control FDT.
 *
 * @path: Full path to node, e.g. "/bus/spi@1"
 * Return: reference to the node found. Use ofnode_valid() to check if it exists
 */
ofnode ofnode_path(const char *path);

/**
 * oftree_path() - find a node by full path from a root node
 *
 * @tree: Device tree to use
 * @path: Full path to node, e.g. "/bus/spi@1"
 * Return: reference to the node found. Use ofnode_valid() to check if it exists
 */
ofnode oftree_path(oftree tree, const char *path);

/**
 * oftree_root() - get the root node of a tree
 *
 * @tree: Device tree to use
 * Return: reference to the root node
 */
ofnode oftree_root(oftree tree);

/**
 * ofnode_read_chosen_prop() - get the value of a chosen property
 *
 * This looks for a property within the /chosen node and returns its value.
 *
 * This only works with the control FDT.
 *
 * @propname: Property name to look for
 * @sizep: Returns size of property, or  `FDT_ERR_...` error code if function
 *  returns NULL
 * Return: property value if found, else NULL
 */
const void *ofnode_read_chosen_prop(const char *propname, int *sizep);

/**
 * ofnode_read_chosen_string() - get the string value of a chosen property
 *
 * This looks for a property within the /chosen node and returns its value,
 * checking that it is a valid nul-terminated string
 *
 * This only works with the control FDT.
 *
 * @propname: Property name to look for
 * Return: string value if found, else NULL
 */
const char *ofnode_read_chosen_string(const char *propname);

/**
 * ofnode_get_chosen_node() - get a referenced node from the chosen node
 *
 * This looks up a named property in the chosen node and uses that as a path to
 * look up a code.
 *
 * This only works with the control FDT.
 *
 * @propname: Property name to look for
 * Return: the referenced node if present, else ofnode_null()
 */
ofnode ofnode_get_chosen_node(const char *propname);

/**
 * ofnode_read_aliases_prop() - get the value of a aliases property
 *
 * This looks for a property within the /aliases node and returns its value
 *
 * This only works with the control FDT.
 *
 * @propname: Property name to look for
 * @sizep: Returns size of property, or `FDT_ERR_...` error code if function
 *  returns NULL
 * Return: property value if found, else NULL
 */
const void *ofnode_read_aliases_prop(const char *propname, int *sizep);

/**
 * ofnode_get_aliases_node() - get a referenced node from the aliases node
 *
 * This looks up a named property in the aliases node and uses that as a path to
 * look up a code.
 *
 * This only works with the control FDT.
 *
 * @propname: Property name to look for
 * Return: the referenced node if present, else ofnode_null()
 */
ofnode ofnode_get_aliases_node(const char *propname);

struct display_timing;
/**
 * ofnode_decode_display_timing() - decode display timings
 *
 * Decode display timings from the supplied 'display-timings' node.
 * See doc/device-tree-bindings/video/display-timing.txt for binding
 * information.
 *
 * @node:   'display-timing' node containing the timing subnodes
 * @index:  Index number to read (0=first timing subnode)
 * @config: Place to put timings
 * Return: 0 if OK, -FDT_ERR_NOTFOUND if not found
 */
int ofnode_decode_display_timing(ofnode node, int index,
                                 struct display_timing *config);

/**
 * ofnode_decode_panel_timing() - decode display timings
 *
 * Decode panel timings from the supplied 'panel-timings' node.
 *
 * @node:   'display-timing' node containing the timing subnodes
 * @config: Place to put timings
 * Return: 0 if OK, -FDT_ERR_NOTFOUND if not found
 */
int ofnode_decode_panel_timing(ofnode node,
                               struct display_timing *config);

/**
 * ofnode_get_property() - get a pointer to the value of a node property
 * 获取node下的属性，如“ofnode_get_property(node, "compatible", &ret)”
 * @node: node to read
 * @propname: property to read
 * @lenp: place to put length on success,如果没有这个属性，*lenp=-1
 * Return: pointer to property, or NULL if not found
 */
const void *ofnode_get_property(ofnode node, const char *propname, int *lenp);
/**
 * ofnode_first_property()- get the reference of the first property
 *
 * Get reference to the first property of the node, it is used to iterate
 * and read all the property with ofprop_get_property().
 *
 * @node: node to read
 * @prop: place to put argument reference
 * Return: 0 if OK, -ve on error. -FDT_ERR_NOTFOUND if not found
 */
int ofnode_first_property(ofnode node, struct ofprop *prop);

/**
 * ofnode_next_property() - get the reference of the next property
 *
 * Get reference to the next property of the node, it is used to iterate
 * and read all the property with ofprop_get_property().
 *
 * @prop: reference of current argument and place to put reference of next one
 * Return: 0 if OK, -ve on error. -FDT_ERR_NOTFOUND if not found
 */
int ofnode_next_property(struct ofprop *prop);

/**
 * ofnode_for_each_prop() - iterate over all properties of a node
 *
 * @prop:   struct ofprop
 * @node:   node (lvalue, ofnode)
 *
 * This is a wrapper around a for loop and is used like this::
 *
 *   ofnode node;
 *   struct ofprop prop;
 *
 *   ofnode_for_each_prop(prop, node) {
 *       ...use prop...
 *   }
 *
 * Note that this is implemented as a macro and @prop is used as
 * iterator in the loop. The parent variable can be a constant or even a
 * literal.
 */
#define ofnode_for_each_prop(prop, node) \
        for (ofnode_first_property(node, &prop); \
             ofprop_valid(&prop); \
             ofnode_next_property(&prop))

/**
 * ofprop_get_property() - get a pointer to the value of a property
 *
 * Get value for the property identified by the provided reference.
 *
 * @prop: reference on property
 * @propname: If non-NULL, place to property name on success,
 * @lenp: If non-NULL, place to put length on success, or error code on failure
 * Return: pointer to property, or NULL if not found
 */
const void *ofprop_get_property(const struct ofprop *prop,
                                const char **propname, int *lenp);

/**
 * ofnode_get_addr_size() - get address and size from a property
 *
 * This does no address translation. It simply reads an property that contains
 * an address and a size value, one after the other.
 *
 * @node: node to read from
 * @propname: property to read
 * @sizep: place to put size value (on success)
 * Return: address value, or FDT_ADDR_T_NONE on error
 */
fdt_addr_t ofnode_get_addr_size(ofnode node, const char *propname,
                                fdt_size_t *sizep);

/**
 * ofnode_read_u8_array_ptr() - find an 8-bit array
 *
 * Look up a property in a node and return a pointer to its contents as a
 * byte array of given length. The property must have at least enough data
 * for the array (count bytes). It may have more, but this will be ignored.
 * The data is not copied.
 *
 * @node:   node to examine
 * @propname:   name of property to find
 * @sz:     number of array elements
 * Return:
 * pointer to byte array if found, or NULL if the property is not found or
 * there is not enough data
 */
const uint8_t *ofnode_read_u8_array_ptr(ofnode node, const char *propname,
                                        size_t sz);

/**
 * ofnode_read_pci_addr() - look up a PCI address
 *
 * Look at an address property in a node and return the PCI address which
 * corresponds to the given type in the form of fdt_pci_addr.
 * The property must hold one fdt_pci_addr with a lengh.
 *
 * @node:   node to examine
 * @type:   pci address type (FDT_PCI_SPACE_xxx)
 * @propname:   name of property to find
 * @addr:   returns pci address in the form of fdt_pci_addr
 * Return:
 * 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
 * format of the property was invalid, -ENXIO if the requested
 * address type was not found
 */
int ofnode_read_pci_addr(ofnode node, enum fdt_pci_space type,
                         const char *propname, struct fdt_pci_addr *addr);

/**
 * ofnode_read_pci_vendev() - look up PCI vendor and device id
 *
 * Look at the compatible property of a device node that represents a PCI
 * device and extract pci vendor id and device id from it.
 *
 * @node:   node to examine
 * @vendor: vendor id of the pci device
 * @device: device id of the pci device
 * Return: 0 if ok, negative on error
 */
int ofnode_read_pci_vendev(ofnode node, u16 *vendor, u16 *device);

/**
 * ofnode_read_eth_phy_id() - look up eth phy vendor and device id
 *
 * Look at the compatible property of a device node that represents a eth phy
 * device and extract phy vendor id and device id from it.
 *
 * @node:   node to examine
 * @vendor: vendor id of the eth phy device
 * @device: device id of the eth phy device
 * Return:   0 if ok, negative on error
 */
int ofnode_read_eth_phy_id(ofnode node, u16 *vendor, u16 *device);

/**
 * ofnode_read_addr_cells() - Get the number of address cells for a node
 *
 * This walks back up the tree to find the closest #address-cells property
 * which controls the given node.
 *
 * @node: Node to check
 * Return: number of address cells this node uses
 */
int ofnode_read_addr_cells(ofnode node);

/**
 * ofnode_read_size_cells() - Get the number of size cells for a node
 *
 * This walks back up the tree to find the closest #size-cells property
 * which controls the given node.
 *
 * @node: Node to check
 * Return: number of size cells this node uses
 */
int ofnode_read_size_cells(ofnode node);

/**
 * ofnode_read_simple_addr_cells() - Get the address cells property in a node
 *
 * This function matches fdt_address_cells().
 *
 * @node: Node to check
 * Return: value of #address-cells property in this node, or 2 if none
 */
int ofnode_read_simple_addr_cells(ofnode node);

/**
 * ofnode_read_simple_size_cells() - Get the size cells property in a node
 *
 * This function matches fdt_size_cells().
 *
 * @node: Node to check
 * Return: value of #size-cells property in this node, or 2 if none
 */
int ofnode_read_simple_size_cells(ofnode node);

/**
 * ofnode_pre_reloc() - check if a node should be bound before relocation
 *
 * Device tree nodes can be marked as needing-to-be-bound in the loader stages
 * via special device tree properties.
 *
 * Before relocation this function can be used to check if nodes are required
 * in either SPL or TPL stages.
 *
 * After relocation and jumping into the real U-Boot binary it is possible to
 * determine if a node was bound in one of SPL/TPL stages.
 *
 * There are 4 settings currently in use
 * - bootph-some-ram: U-Boot proper pre-relocation only
 * - bootph-all: all phases
 * Existing platforms only use it to indicate nodes needed in
 * SPL. Should probably be replaced by bootph-pre-ram for new platforms.
 * - bootph-pre-ram: SPL and U-Boot pre-relocation
 * - bootph-pre-sram: TPL and U-Boot pre-relocation
 *
 * @node: node to check
 * Return: true if node is needed in SPL/TL, false otherwise
 */
bool ofnode_pre_reloc(ofnode node);

/**
 * ofnode_read_resource() - Read a resource from a node
 *
 * Read resource information from a node at the given index
 *
 * @node: Node to read from
 * @index: Index of resource to read (0 = first)
 * @res: Returns resource that was read, on success
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_resource(ofnode node, uint index, struct resource *res);

/**
 * ofnode_read_resource_byname() - Read a resource from a node by name
 *
 * Read resource information from a node matching the given name. This uses a
 * 'reg-names' string list property with the names matching the associated
 * 'reg' property list.
 *
 * @node: Node to read from
 * @name: Name of resource to read
 * @res: Returns resource that was read, on success
 * Return: 0 if OK, -ve on error
 */
int ofnode_read_resource_byname(ofnode node, const char *name,
                                struct resource *res);

/**
 * ofnode_by_compatible() - Find the next compatible node
 *
 * Find the next node after @from that is compatible with @compat
 *
 * @from: ofnode to start from (use ofnode_null() to start at the beginning)
 * @compat: Compatible string to match
 * Return: ofnode found, or ofnode_null() if none
 */
ofnode ofnode_by_compatible(ofnode from, const char *compat);

/**
 * ofnode_by_prop_value() - Find the next node with given property value
 *
 * Find the next node after @from that has a @propname with a value
 * @propval and a length @proplen.
 *
 * @from: ofnode to start from. Use ofnode_null() to start at the
 * beginning, or the return value from oftree_root() to start at the first
 * child of the root
 * @propname: property name to check
 * @propval: property value to search for
 * @proplen: length of the value in propval
 * Return: ofnode found, or ofnode_null() if none
 */
ofnode ofnode_by_prop_value(ofnode from, const char *propname,
                            const void *propval, int proplen);

/**
 * ofnode_for_each_subnode() - iterate over all subnodes of a parent
 *
 * @node:       child node (ofnode, lvalue)
 * @parent:     parent node (ofnode)
 *
 * This is a wrapper around a for loop and is used like so::
 *
 *   ofnode node;
 *   ofnode_for_each_subnode(node, parent) {
 *       Use node
 *       ...
 *   }
 *
 * Note that this is implemented as a macro and @node is used as
 * iterator in the loop. The parent variable can be a constant or even a
 * literal.
 */
#define ofnode_for_each_subnode(node, parent) \
        for (node = ofnode_first_subnode(parent); \
             ofnode_valid(node); \
             node = ofnode_next_subnode(node))

/**
 * ofnode_for_each_compatible_node() - iterate over all nodes with a given
 *                     compatible string
 *
 * @node:       child node (ofnode, lvalue)
 * @compat:     compatible string to match
 *
 * This is a wrapper around a for loop and is used like so::
 *
 *   ofnode node;
 *   ofnode_for_each_compatible_node(node, parent, compatible) {
 *      Use node
 *      ...
 *   }
 *
 * Note that this is implemented as a macro and @node is used as
 * iterator in the loop.
 */
#define ofnode_for_each_compatible_node(node, compat) \
        for (node = ofnode_by_compatible(ofnode_null(), compat); \
             ofnode_valid(node); \
             node = ofnode_by_compatible(node, compat))

/**
 * ofnode_get_child_count() - get the child count of a ofnode
 *
 * @parent: valid node to get its child count
 * Return: the number of subnodes
 */
int ofnode_get_child_count(ofnode parent);

/**
 * ofnode_translate_address() - Translate a device-tree address
 *
 * Translate an address from the device-tree into a CPU physical address. This
 * function walks up the tree and applies the various bus mappings along the
 * way.
 *
 * @node: Device tree node giving the context in which to translate the address
 * @in_addr: pointer to the address to translate
 * Return: the translated address; OF_BAD_ADDR on error
 */
u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr);

/**
 * ofnode_translate_dma_address() - Translate a device-tree DMA address
 *
 * Translate a DMA address from the device-tree into a CPU physical address.
 * This function walks up the tree and applies the various bus mappings along
 * the way.
 *
 * @node: Device tree node giving the context in which to translate the
 *        DMA address
 * @in_addr: pointer to the DMA address to translate
 * Return: the translated DMA address; OF_BAD_ADDR on error
 */
u64 ofnode_translate_dma_address(ofnode node, const fdt32_t *in_addr);

/**
 * ofnode_get_dma_range() - get dma-ranges for a specific DT node
 *
 * Get DMA ranges for a specifc node, this is useful to perform bus->cpu and
 * cpu->bus address translations
 *
 * @node: Device tree node
 * @cpu: Pointer to variable storing the range's cpu address
 * @bus: Pointer to variable storing the range's bus address
 * @size: Pointer to variable storing the range's size
 * Return: translated DMA address or OF_BAD_ADDR on error
 */
int ofnode_get_dma_range(ofnode node, phys_addr_t *cpu, dma_addr_t *bus,
                         u64 *size);

/**
 * ofnode_device_is_compatible() - check if the node is compatible with compat
 *
 * This allows to check whether the node is comaptible with the compat.
 *
 * @node:   Device tree node for which compatible needs to be verified.
 * @compat: Compatible string which needs to verified in the given node.
 * Return: true if OK, false if the compatible is not found
 */
int ofnode_device_is_compatible(ofnode node, const char *compat);

/**
 * ofnode_write_prop() - Set a property of a ofnode
 *
 * Note that if @copy is false, the value passed to the function is *not*
 * allocated by the function itself, but must be allocated by the caller if
 * necessary. However it does allocate memory for the property struct and name.
 *
 * @node:   The node for whose property should be set
 * @propname:   The name of the property to set
 * @value:  The new value of the property (must be valid prior to calling
 *      the function)
 * @len:    The length of the new value of the property
 * @copy: true to allocate memory for the value. This only has any effect with
 *  live tree, since flat tree handles this automatically. It allows a
 *  node's value to be written to the tree, without requiring that the
 *  caller allocate it
 * Return: 0 if successful, -ve on error
 */
int ofnode_write_prop(ofnode node, const char *propname, const void *value,
                      int len, bool copy);

/**
 * ofnode_write_string() - Set a string property of a ofnode
 *
 * Note that the value passed to the function is *not* allocated by the
 * function itself, but must be allocated by the caller if necessary.
 *
 * @node:   The node for whose string property should be set
 * @propname:   The name of the string property to set
 * @value:  The new value of the string property (must be valid prior to
 *      calling the function)
 * Return: 0 if successful, -ve on error
 */
int ofnode_write_string(ofnode node, const char *propname, const char *value);

/**
 * ofnode_write_u32() - Set an integer property of an ofnode
 *
 * @node:   The node for whose string property should be set
 * @propname:   The name of the string property to set
 * @value:  The new value of the 32-bit integer property
 * Return: 0 if successful, -ve on error
 */
int ofnode_write_u32(ofnode node, const char *propname, u32 value);

/**
 * ofnode_set_enabled() - Enable or disable a device tree node given by its
 *            ofnode
 *
 * This function effectively sets the node's "status" property to either "okay"
 * or "disable", hence making it available for driver model initialization or
 * not.
 *
 * @node:   The node to enable
 * @value:  Flag that tells the function to either disable or enable the
 *      node
 * Return: 0 if successful, -ve on error
 */
int ofnode_set_enabled(ofnode node, bool value);

/**
 * ofnode_get_phy_node() - Get PHY node for a MAC (if not fixed-link)
 *
 * This function parses PHY handle from the Ethernet controller's ofnode
 * (trying all possible PHY handle property names), and returns the PHY ofnode.
 *
 * Before this is used, ofnode_phy_is_fixed_link() should be checked first, and
 * if the result to that is true, this function should not be called.
 *
 * @eth_node:   ofnode belonging to the Ethernet controller
 * Return: ofnode of the PHY, if it exists, otherwise an invalid ofnode
 */
ofnode ofnode_get_phy_node(ofnode eth_node);

/**
 * ofnode_read_phy_mode() - Read PHY connection type from a MAC node
 *
 * This function parses the "phy-mode" / "phy-connection-type" property and
 * returns the corresponding PHY interface type.
 *
 * @mac_node:   ofnode containing the property
 * Return: one of PHY_INTERFACE_MODE_* constants, PHY_INTERFACE_MODE_NA on
 *     error
 */
phy_interface_t ofnode_read_phy_mode(ofnode mac_node);

/**
 * ofnode_conf_read_bool() - Read a boolean value from the U-Boot config
 * This reads a property from the /config node of the devicetree.
 *
 * This only works with the control FDT.
 *
 * See doc/device-tree-bindings/config.txt for bindings
 *
 * @prop_name:  property name to look up
 * Return: true, if it exists, false if not
 */
bool ofnode_conf_read_bool(const char *prop_name);

/**
 * ofnode_conf_read_int() - Read an integer value from the U-Boot config
 *
 * This reads a property from the /config node of the devicetree.
 *
 * See doc/device-tree-bindings/config.txt for bindings
 *
 * @prop_name: property name to look up
 * @default_val: default value to return if the property is not found
 * Return: integer value, if found, or @default_val if not
 */
int ofnode_conf_read_int(const char *prop_name, int default_val);

/**
 * ofnode_conf_read_str() - Read a string value from the U-Boot config
 *
 * This reads a property from the /config node of the devicetree.
 *
 * This only works with the control FDT.
 *
 * See doc/device-tree-bindings/config.txt for bindings
 *
 * @prop_name: property name to look up
 * Return: string value, if found, or NULL if not
 */
const char *ofnode_conf_read_str(const char *prop_name);

/**
 * of_add_subnode() - add a new subnode to a node
 *
 * @parent: parent node to add to
 * @name:   name of subnode
 * @nodep:  returns pointer to new subnode (valid if the function returns 0
 *  or -EEXIST)
 * Returns 0 if OK, -EEXIST if already exists, -ENOMEM if out of memory, other
 * -ve on other error
 */
int ofnode_add_subnode(ofnode parent, const char *name, ofnode *nodep);

/**
 * ofnode_copy_props() - copy all properties from one node to another
 *
 * Makes a copy of all properties from the source note in the destination node.
 * Existing properties in the destination node remain unchanged, except that
 * any with the same name are overwritten, including changing the size of the
 * property.
 *
 * For livetree, properties are copied / allocated, so the source tree does not
 * need to be present afterwards.
 *
 * @src: Source node to read properties from
 * @dst: Destination node to write properties too
 */
int ofnode_copy_props(ofnode src, ofnode dst);

/**
 * lists_driver_lookup_name() - Return u_boot_driver corresponding to name
 * 根据name查找driver结构体（U_BOOT_DRIVER(pinconfig_generic)）
 * This function returns a pointer to a driver given its name. This is used
 * for binding a driver given its name and plat.
 *
 * @name: Name of driver to look up
 * Return: pointer to driver, or NULL if not found
 */
struct driver *lists_driver_lookup_name(const char *name);

/**
 * lists_uclass_lookup() - Return uclass_driver based on ID of the class
 *
 * @id:     ID of the class
 *
 * This function returns the pointer to uclass_driver, which is the class's
 * base structure based on the ID of the class. Returns NULL on error.
 */
struct uclass_driver *lists_uclass_lookup(enum uclass_id id);

/**
 * lists_bind_drivers() - search for and bind all drivers to parent
 *
 * This searches the U_BOOT_DRVINFO() structures and creates new devices for
 * each one. The devices will have @parent as their parent.
 *
 * @parent: parent device (root)
 * @pre_reloc_only: If true, bind only drivers with the DM_FLAG_PRE_RELOC flag.
 * If false bind all drivers.
 */
int lists_bind_drivers(struct udevice *parent, bool pre_reloc_only);

/**
 * lists_bind_fdt() - bind a device tree node
 *
 * This creates a new device bound to the given device tree node, with
 * @parent as its parent.
 *
 * @parent: parent device (root)
 * @node: device tree node to bind
 * @devp: if non-NULL, returns a pointer to the bound device
 * @drv: if non-NULL, force this driver to be bound
 * @pre_reloc_only: If true, bind only nodes with special devicetree properties,
 * or drivers with the DM_FLAG_PRE_RELOC flag. If false bind all drivers.
 *
 * Return: 0 if device was bound, -EINVAL if the device tree is invalid,
 * other -ve value on error
 */
int lists_bind_fdt(struct udevice *parent, ofnode node, struct udevice **devp,
                   struct driver *drv, bool pre_reloc_only);

/**
 * device_bind_driver() - bind a device to a driver
 *
 * This binds a new device to a driver.
 *
 * @parent: Parent device
 * @drv_name:   Name of driver to attach to this parent
 * @dev_name:   Name of the new device thus created
 * @devp:   If non-NULL, returns the newly bound device
 * Return: 0 if OK, -ve on error
 */
int device_bind_driver(struct udevice *parent, const char *drv_name,
                       const char *dev_name, struct udevice **devp);

/**
 * device_bind_driver_to_node() - bind a device to a driver for a node
 *
 * This binds a new device to a driver for a given device tree node. This
 * should only be needed if the node lacks a compatible strings.
 *
 * @parent: Parent device
 * @drv_name:   Name of driver to attach to this parent
 * @dev_name:   Name of the new device thus created
 * @node:   Device tree node
 * @devp:   If non-NULL, returns the newly bound device
 * Return: 0 if OK, -ve on error
 */
int device_bind_driver_to_node(struct udevice *parent, const char *drv_name,
                               const char *dev_name, ofnode node,
                               struct udevice **devp);

struct device_node;
struct driver_info;
struct udevice;

/**
 * DM_DEVICE_INST() - Declare a bound device ready for run-time use
 *
 * This adds an actual struct udevice to a list which is found by driver model
 * on start-up.
 *
 * For example:
 *
 * extern U_BOOT_DRIVER(sandbox_fixed_clock);
 * extern DM_UCLASS_INST(clk);
 *
 * DM_DEVICE_INST(clk_fixed) = {
 *  .driver     = DM_DRIVER_REF(sandbox_fixed_clock),
 *  .name       = "sandbox_fixed_clock",
 *  .plat_      = &_sandbox_fixed_clock_plat_clk_fixed,
 *  .uclass     = DM_UCLASS_REF(clk),
 *  ...
 *  .seq_       = 0,
 * };
 *
 * @_name: Name of the udevice. This must be a valid C identifier, used by the
 *  linker_list.
 */
#define DM_DEVICE_INST(_name)                       \
        ll_entry_declare(struct udevice, _name, udevice)

/**
 * DM_DEVICE_REF() - Get a reference to a device
 *
 * This is useful in data structures and code for referencing a udevice at
 * build time. Before this is used, an extern DM_DEVICE_INST() must have been
 * declared.
 *
 * For example:
 *
 * extern DM_DEVICE_INST(clk_fixed);
 *
 * struct udevice *devs[] = {
 *  DM_DEVICE_REF(clk_fixed),
 * };
 *
 * @_name: Name of the udevice. This must be a valid C identifier, used by the
 *  linker_list
 * @returns struct udevice * for the device
 */
#define DM_DEVICE_REF(_name)                        \
        ll_entry_ref(struct udevice, _name, udevice)

/**
 * DM_DEVICE_GET() - Get a pointer to a given device
 *
 * This is similar to DM_DEVICE_REF() except that it does not need the extern
 * declaration before it. However it cannot be used in a data structures, only
 * in code within a function.
 *
 * For example:
 *
 * void some_function() {
 *  struct udevice *dev = DM_DEVICE_GET(clk_fixed);
 * ...
 * }
 */
#define DM_DEVICE_GET(__name)                       \
        ll_entry_get(struct udevice, __name, udevice)

/**
 * device_bind() - Create a device and bind it to a driver
 *
 * Called to set up a new device attached to a driver. The device will either
 * have plat, or a device tree node which can be used to create the
 * plat.
 *
 * Once bound a device exists but is not yet active until device_probe() is
 * called.
 *
 * @parent: Pointer to device's parent, under which this driver will exist
 * @drv: Device's driver
 * @name: Name of device (e.g. device tree node name)
 * @plat: Pointer to data for this device - the structure is device-
 * specific but may include the device's I/O address, etc.. This is NULL for
 * devices which use device tree.
 * @ofnode: Devicetree node for this device. This is ofnode_null() for
 * devices which don't use devicetree or don't have a node.
 * @devp: if non-NULL, returns a pointer to the bound device
 * Return: 0 if OK, -ve on error
 */
int device_bind(struct udevice *parent, const struct driver *drv,
                const char *name, void *plat, ofnode node,
                struct udevice **devp);

/**
 * device_bind_with_driver_data() - Create a device and bind it to a driver
 *
 * Called to set up a new device attached to a driver, in the case where the
 * driver was matched to the device by means of a match table that provides
 * driver_data.
 *
 * Once bound a device exists but is not yet active until device_probe() is
 * called.
 *
 * @parent: Pointer to device's parent, under which this driver will exist
 * @drv: Device's driver
 * @name: Name of device (e.g. device tree node name)
 * @driver_data: The driver_data field from the driver's match table.
 * @node: Device tree node for this device. This is invalid for devices which
 * don't use device tree.
 * @devp: if non-NULL, returns a pointer to the bound device
 * Return: 0 if OK, -ve on error
 */
int device_bind_with_driver_data(struct udevice *parent,
                                 const struct driver *drv, const char *name,
                                 ulong driver_data, ofnode node,
                                 struct udevice **devp);
/**
 * device_bind_by_name: Create a device and bind it to a driver
 *
 * This is a helper function used to bind devices which do not use device
 * tree.
 *
 * @parent: Pointer to device's parent
 * @pre_reloc_only: If true, bind the driver only if its DM_FLAG_PRE_RELOC flag
 * is set. If false bind the driver always.
 * @info: Name and plat for this device
 * @devp: if non-NULL, returns a pointer to the bound device
 * Return: 0 if OK, -ve on error
 */
int device_bind_by_name(struct udevice *parent, bool pre_reloc_only,
                        const struct driver_info *info, struct udevice **devp);

/**
 * device_reparent: reparent the device to a new parent
 *
 * @dev: pointer to device to be reparented
 * @new_parent: pointer to new parent device
 * Return: 0 if OK, -ve on error
 */
int device_reparent(struct udevice *dev, struct udevice *new_parent);

/**
 * device_of_to_plat() - Read platform data for a device
 *
 * Read platform data for a device (typically from the device tree) so that
 * the information needed to probe the device is present.
 *
 * This may cause some others devices to be probed if this one depends on them,
 * e.g. a GPIO line will cause a GPIO device to be probed.
 *
 * All private data associated with the device is allocated.
 *
 * @dev: Pointer to device to process
 * Return: 0 if OK, -ve on error
 */
int device_of_to_plat(struct udevice *dev);

/**
 * device_probe() - Probe a device, activating it
 *
 * Activate a device (if not yet activated) so that it is ready for use.
 * All its parents are probed first.
 *
 * @dev: Pointer to device to probe
 * Return: 0 if OK, -ve on error
 */
int device_probe(struct udevice *dev);

/**
 * device_remove() - Remove a device, de-activating it
 *
 * De-activate a device so that it is no longer ready for use. All its
 * children are deactivated first.
 *
 * @dev: Pointer to device to remove
 * @flags: Flags for selective device removal (DM_REMOVE_...)
 * Return: 0 if OK, -EKEYREJECTED if not removed due to flags, -EPROBE_DEFER if
 *  this is a vital device and flags is DM_REMOVE_NON_VITAL, other -ve on
 *  error (such an error here is normally a very bad thing)
 */
int device_remove(struct udevice *dev, uint flags);

/**
 * device_unbind() - Unbind a device, destroying it
 *
 * Unbind a device and remove all memory used by it
 *
 * @dev: Pointer to device to unbind
 * Return: 0 if OK, -ve on error
 */
int device_unbind(struct udevice *dev);
void device_free(struct udevice *dev);

/**
 * device_chld_unbind() - Unbind all device's children from the device if bound
 *            to drv
 *
 * On error, the function continues to unbind all children, and reports the
 * first error.
 *
 * @dev:    The device that is to be stripped of its children
 * @drv:    The targeted driver
 * Return: 0 on success, -ve on error
 */
int device_chld_unbind(struct udevice *dev, struct driver *drv);
/**
 * device_chld_remove() - Stop all device's children
 *
 * This continues through all children recursively stopping part-way through if
 * an error occurs. Return values of -EKEYREJECTED are ignored and processing
 * continues, since they just indicate that the child did not elect to be
 * removed based on the value of @flags. Return values of -EPROBE_DEFER cause
 * processing of other children to continue, but the function will return
 * -EPROBE_DEFER.
 *
 * @dev:    The device whose children are to be removed
 * @drv:    The targeted driver
 * @flags:  Flag, if this functions is called in the pre-OS stage
 * Return: 0 on success, -EPROBE_DEFER if any child failed to remove, other
 *  -ve on error
 */
int device_chld_remove(struct udevice *dev, struct driver *drv,uint flags);
/**
 * dev_set_priv() - Set the private data for a device
 *
 * This is normally handled by driver model, which automatically allocates
 * private data when an 'auto' size if provided by the driver.
 *
 * Use this function to override normal operation for special situations, such
 * as needing to allocate a variable amount of data.
 *
 * If OF_PLATDATA_RT is enabled, this function cannot be used out of core driver
 * model code, since the pointer must be within the gd->dm_priv_base region.
 *
 * @dev     Device to check
 * @priv    New private-data pointer
 */
void dev_set_priv(struct udevice *dev, void *priv);

/**
 * dev_set_parent_priv() - Set the parent-private data for a device
 *
 * This is normally handled by driver model, which automatically allocates
 * parent-private data when an 'auto' size if provided by the driver.
 *
 * Use this function to override normal operation for special situations, such
 * as needing to allocate a variable amount of data.
 *
 * If OF_PLATDATA_RT is enabled, this function cannot be used out of core driver
 * model code, since the pointer must be within the gd->dm_priv_base region.
 *
 * @dev:    Device to update
 * @parent_priv: New parent-private data
 */
void dev_set_parent_priv(struct udevice *dev, void *parent_priv);

/**
 * dev_set_uclass_priv() - Set the uclass private data for a device
 *
 * This is normally handled by driver model, which automatically allocates
 * uclass-private data when an 'auto' size if provided by the driver.
 *
 * Use this function to override normal operation for special situations, such
 * as needing to allocate a variable amount of data.
 *
 * If OF_PLATDATA_RT is enabled, this function cannot be used out of core driver
 * model code, since the pointer must be within the gd->dm_priv_base region.
 *
 * @dev:    Device to update
 * @uclass_priv: New uclass private data
 */
void dev_set_uclass_priv(struct udevice *dev, void *uclass_priv);

/**
 * dev_set_plat() - Set the platform data for a device
 *
 * This is normally handled by driver model, which automatically allocates
 * platform data when an 'auto' size if provided by the driver.
 *
 * Use this function to override normal operation for special situations, such
 * as needing to allocate a variable amount of data.
 *
 * If OF_PLATDATA_RT is enabled, this function cannot be used out of core driver
 * model code, since the pointer must be within the gd->dm_priv_base region.
 *
 * @dev     Device to check
 * @plat    New platform-data pointer
 */
void dev_set_plat(struct udevice *dev, void *priv);

/**
 * dev_set_parent_plat() - Set the parent platform data for a device
 *
 * This is normally handled by driver model, which automatically allocates
 * parent platform data when an 'auto' size if provided by the driver.
 *
 * Use this function to override normal operation for special situations, such
 * as needing to allocate a variable amount of data.
 *
 * If OF_PLATDATA_RT is enabled, this function cannot be used out of core driver
 * model code, since the pointer must be within the gd->dm_priv_base region.
 *
 * @dev:    Device to update
 * @parent_plat: New parent platform data
 */
void dev_set_parent_plat(struct udevice *dev, void *parent_plat);

/**
 * dev_set_uclass_plat() - Set the uclass platform data for a device
 *
 * This is normally handled by driver model, which automatically allocates
 * uclass platform data when an 'auto' size if provided by the driver.
 *
 * Use this function to override normal operation for special situations, such
 * as needing to allocate a variable amount of data.
 *
 * If OF_PLATDATA_RT is enabled, this function cannot be used out of core driver
 * model code, since the pointer must be within the gd->dm_priv_base region.
 *
 * @dev:    Device to update
 * @uclass_plat: New uclass platform data
 */
void dev_set_uclass_plat(struct udevice *dev, void *uclass_plat);

/**
 * simple_bus_translate() - translate a bus address to a system address
 *
 * This handles the 'ranges' property in a simple bus. It translates the
 * device address @addr to a system address using this property.
 *
 * @dev:    Simple bus device (parent of target device)
 * @addr:   Address to translate
 * Return: new address
 */
fdt_addr_t simple_bus_translate(struct udevice *dev, fdt_addr_t addr);

/* Cast away any volatile pointer */
#define DM_ROOT_NON_CONST       (((gd_t *)gd)->dm_root)
#define DM_UCLASS_ROOT_NON_CONST    (((gd_t *)gd)->uclass_root)
#define DM_UCLASS_ROOT_S_NON_CONST  (((gd_t *)gd)->uclass_root_s)

/**
 * devres_release_probe - Release managed resources allocated after probing
 * @dev: Device to release resources for
 *
 * Release all resources allocated for @dev when it was probed or later.
 * This function is called on driver removal.
 */
void devres_release_probe(struct udevice *dev);

/**
 * devres_release_all - Release all managed resources
 * @dev: Device to release resources for
 *
 * Release all resources associated with @dev.  This function is
 * called on driver unbinding.
 */
void devres_release_all(struct udevice *dev);

static inline int device_notify(const struct udevice *dev, enum event_t type)