1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Copyright (c) 2013 Google, Inc
6 * Pavel Herrmann <morpheus.ibis@gmail.com>
7 * Marek Vasut <marex@denx.de>
13 #include <dm/ofnode.h>
14 #include <dm/uclass-id.h>
16 #include <linker_lists.h>
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 #include <linux/printk.h>
23 /* Driver is active (probed). Cleared when it is removed */
24 #define DM_FLAG_ACTIVATED (1 << 0)
26 /* DM is responsible for allocating and freeing platdata */
27 #define DM_FLAG_ALLOC_PDATA (1 << 1)
29 /* DM should init this device prior to relocation */
30 #define DM_FLAG_PRE_RELOC (1 << 2)
32 /* DM is responsible for allocating and freeing parent_platdata */
33 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
35 /* DM is responsible for allocating and freeing uclass_platdata */
36 #define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4)
38 /* Allocate driver private data on a DMA boundary */
39 #define DM_FLAG_ALLOC_PRIV_DMA (1 << 5)
42 #define DM_FLAG_BOUND (1 << 6)
44 /* Device name is allocated and should be freed on unbind() */
45 #define DM_FLAG_NAME_ALLOCED (1 << 7)
47 /* Device has platform data provided by of-platdata */
48 #define DM_FLAG_OF_PLATDATA (1 << 8)
51 * Call driver remove function to stop currently active DMA transfers or
52 * give DMA buffers back to the HW / controller. This may be needed for
53 * some drivers to do some final stage cleanup before the OS is called
56 #define DM_FLAG_ACTIVE_DMA (1 << 9)
59 * Call driver remove function to do some final configuration, before
60 * U-Boot exits and the OS is started
62 #define DM_FLAG_OS_PREPARE (1 << 10)
64 /* DM does not enable/disable the power domains corresponding to this device */
65 #define DM_FLAG_DEFAULT_PD_CTRL_OFF (1 << 11)
67 /* Driver platdata has been read. Cleared when the device is removed */
68 #define DM_FLAG_PLATDATA_VALID (1 << 12)
71 * Device is removed without switching off its power domain. This might
72 * be required, i. e. for serial console (debug) output when booting OS.
74 #define DM_FLAG_REMOVE_WITH_PD_ON (1 << 13)
77 * One or multiple of these flags are passed to device_remove() so that
78 * a selective device removal as specified by the remove-stage and the
79 * driver flags can be done.
82 /* Normal remove, remove all devices */
83 DM_REMOVE_NORMAL = 1 << 0,
85 /* Remove devices with active DMA */
86 DM_REMOVE_ACTIVE_DMA = DM_FLAG_ACTIVE_DMA,
88 /* Remove devices which need some final OS preparation steps */
89 DM_REMOVE_OS_PREPARE = DM_FLAG_OS_PREPARE,
91 /* Add more use cases here */
93 /* Remove devices with any active flag */
94 DM_REMOVE_ACTIVE_ALL = DM_REMOVE_ACTIVE_DMA | DM_REMOVE_OS_PREPARE,
98 * struct udevice - An instance of a driver
100 * This holds information about a device, which is a driver bound to a
101 * particular port or peripheral (essentially a driver instance).
103 * A device will come into existence through a 'bind' call, either due to
104 * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node
105 * in the device tree (in which case of_offset is >= 0). In the latter case
106 * we translate the device tree information into platdata in a function
107 * implemented by the driver ofdata_to_platdata method (called just before the
108 * probe method if the device has a device tree node.
110 * All three of platdata, priv and uclass_priv can be allocated by the
111 * driver, or you can use the auto_alloc_size members of struct driver and
112 * struct uclass_driver to have driver model do this automatically.
114 * @driver: The driver used by this device
115 * @name: Name of device, typically the FDT node name
116 * @platdata: Configuration data for this device
117 * @parent_platdata: The parent bus's configuration data for this device
118 * @uclass_platdata: The uclass's configuration data for this device
119 * @node: Reference to device tree node for this device
120 * @driver_data: Driver data word for the entry that matched this device with
122 * @parent: Parent of this device, or NULL for the top level device
123 * @priv: Private data for this device
124 * @uclass: Pointer to uclass for this device
125 * @uclass_priv: The uclass's private data for this device
126 * @parent_priv: The parent's private data for this device
127 * @uclass_node: Used by uclass to link its devices
128 * @child_head: List of children of this device
129 * @sibling_node: Next device in list of all devices
130 * @flags: Flags for this device DM_FLAG_...
131 * @req_seq: Requested sequence number for this device (-1 = any)
132 * @seq: Allocated sequence number for this device (-1 = none). This is set up
133 * when the device is probed and will be unique within the device's uclass.
134 * @devres_head: List of memory allocations associated with this device.
135 * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
136 * add to this list. Memory so-allocated will be freed
137 * automatically when the device is removed / unbound
140 const struct driver *driver;
143 void *parent_platdata;
144 void *uclass_platdata;
147 struct udevice *parent;
149 struct uclass *uclass;
152 struct list_head uclass_node;
153 struct list_head child_head;
154 struct list_head sibling_node;
159 struct list_head devres_head;
163 /* Maximum sequence number supported */
164 #define DM_MAX_SEQ 999
166 /* Returns the operations for a device */
167 #define device_get_ops(dev) (dev->driver->ops)
169 /* Returns non-zero if the device is active (probed and not removed) */
170 #define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED)
172 static inline int dev_of_offset(const struct udevice *dev)
174 return ofnode_to_offset(dev->node);
177 static inline void dev_set_of_offset(struct udevice *dev, int of_offset)
179 dev->node = offset_to_ofnode(of_offset);
182 static inline bool dev_has_of_node(struct udevice *dev)
184 return ofnode_valid(dev->node);
188 * struct udevice_id - Lists the compatible strings supported by a driver
189 * @compatible: Compatible string
190 * @data: Data for this compatible string
193 const char *compatible;
197 #if CONFIG_IS_ENABLED(OF_CONTROL)
198 #define of_match_ptr(_ptr) (_ptr)
200 #define of_match_ptr(_ptr) NULL
201 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
204 * struct driver - A driver for a feature or peripheral
206 * This holds methods for setting up a new device, and also removing it.
207 * The device needs information to set itself up - this is provided either
208 * by platdata or a device tree node (which we find by looking up
209 * matching compatible strings with of_match).
211 * Drivers all belong to a uclass, representing a class of devices of the
212 * same type. Common elements of the drivers can be implemented in the uclass,
213 * or the uclass can provide a consistent interface to the drivers within
217 * @id: Identifies the uclass we belong to
218 * @of_match: List of compatible strings to match, and any identifying data
220 * @bind: Called to bind a device to its driver
221 * @probe: Called to probe a device, i.e. activate it
222 * @remove: Called to remove a device, i.e. de-activate it
223 * @unbind: Called to unbind a device from its driver
224 * @ofdata_to_platdata: Called before probe to decode device tree data
225 * @child_post_bind: Called after a new child has been bound
226 * @child_pre_probe: Called before a child device is probed. The device has
227 * memory allocated but it has not yet been probed.
228 * @child_post_remove: Called after a child device is removed. The device
229 * has memory allocated but its device_remove() method has been called.
230 * @priv_auto_alloc_size: If non-zero this is the size of the private data
231 * to be allocated in the device's ->priv pointer. If zero, then the driver
232 * is responsible for allocating any data required.
233 * @platdata_auto_alloc_size: If non-zero this is the size of the
234 * platform data to be allocated in the device's ->platdata pointer.
235 * This is typically only useful for device-tree-aware drivers (those with
236 * an of_match), since drivers which use platdata will have the data
237 * provided in the U_BOOT_DEVICE() instantiation.
238 * @per_child_auto_alloc_size: Each device can hold private data owned by
239 * its parent. If required this will be automatically allocated if this
241 * @per_child_platdata_auto_alloc_size: A bus likes to store information about
242 * its children. If non-zero this is the size of this data, to be allocated
243 * in the child's parent_platdata pointer.
244 * @ops: Driver-specific operations. This is typically a list of function
245 * pointers defined by the driver, to implement driver functions required by
247 * @flags: driver flags - see DM_FLAGS_...
248 * @acpi_ops: Advanced Configuration and Power Interface (ACPI) operations,
249 * allowing the device to add things to the ACPI tables passed to Linux
254 const struct udevice_id *of_match;
255 int (*bind)(struct udevice *dev);
256 int (*probe)(struct udevice *dev);
257 int (*remove)(struct udevice *dev);
258 int (*unbind)(struct udevice *dev);
259 int (*ofdata_to_platdata)(struct udevice *dev);
260 int (*child_post_bind)(struct udevice *dev);
261 int (*child_pre_probe)(struct udevice *dev);
262 int (*child_post_remove)(struct udevice *dev);
263 int priv_auto_alloc_size;
264 int platdata_auto_alloc_size;
265 int per_child_auto_alloc_size;
266 int per_child_platdata_auto_alloc_size;
267 const void *ops; /* driver-specific operations */
269 #if CONFIG_IS_ENABLED(ACPIGEN)
270 struct acpi_ops *acpi_ops;
274 /* Declare a new U-Boot driver */
275 #define U_BOOT_DRIVER(__name) \
276 ll_entry_declare(struct driver, __name, driver)
278 /* Get a pointer to a given driver */
279 #define DM_GET_DRIVER(__name) \
280 ll_entry_get(struct driver, __name, driver)
283 * dev_get_platdata() - Get the platform data for a device
285 * This checks that dev is not NULL, but no other checks for now
287 * @dev Device to check
288 * @return platform data, or NULL if none
290 void *dev_get_platdata(const struct udevice *dev);
293 * dev_get_parent_platdata() - Get the parent platform data for a device
295 * This checks that dev is not NULL, but no other checks for now
297 * @dev Device to check
298 * @return parent's platform data, or NULL if none
300 void *dev_get_parent_platdata(const struct udevice *dev);
303 * dev_get_uclass_platdata() - Get the uclass platform data for a device
305 * This checks that dev is not NULL, but no other checks for now
307 * @dev Device to check
308 * @return uclass's platform data, or NULL if none
310 void *dev_get_uclass_platdata(const struct udevice *dev);
313 * dev_get_priv() - Get the private data for a device
315 * This checks that dev is not NULL, but no other checks for now
317 * @dev Device to check
318 * @return private data, or NULL if none
320 void *dev_get_priv(const struct udevice *dev);
323 * dev_get_parent_priv() - Get the parent private data for a device
325 * The parent private data is data stored in the device but owned by the
326 * parent. For example, a USB device may have parent data which contains
327 * information about how to talk to the device over USB.
329 * This checks that dev is not NULL, but no other checks for now
331 * @dev Device to check
332 * @return parent data, or NULL if none
334 void *dev_get_parent_priv(const struct udevice *dev);
337 * dev_get_uclass_priv() - Get the private uclass data for a device
339 * This checks that dev is not NULL, but no other checks for now
341 * @dev Device to check
342 * @return private uclass data for this device, or NULL if none
344 void *dev_get_uclass_priv(const struct udevice *dev);
347 * struct dev_get_parent() - Get the parent of a device
349 * @child: Child to check
350 * @return parent of child, or NULL if this is the root device
352 struct udevice *dev_get_parent(const struct udevice *child);
355 * dev_get_driver_data() - get the driver data used to bind a device
357 * When a device is bound using a device tree node, it matches a
358 * particular compatible string in struct udevice_id. This function
359 * returns the associated data value for that compatible string. This is
360 * the 'data' field in struct udevice_id.
362 * As an example, consider this structure:
363 * static const struct udevice_id tegra_i2c_ids[] = {
364 * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
365 * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
366 * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
370 * When driver model finds a driver for this it will store the 'data' value
371 * corresponding to the compatible string it matches. This function returns
372 * that value. This allows the driver to handle several variants of a device.
374 * For USB devices, this is the driver_info field in struct usb_device_id.
376 * @dev: Device to check
377 * @return driver data (0 if none is provided)
379 ulong dev_get_driver_data(const struct udevice *dev);
382 * dev_get_driver_ops() - get the device's driver's operations
384 * This checks that dev is not NULL, and returns the pointer to device's
385 * driver's operations.
387 * @dev: Device to check
388 * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
390 const void *dev_get_driver_ops(const struct udevice *dev);
393 * device_get_uclass_id() - return the uclass ID of a device
395 * @dev: Device to check
396 * @return uclass ID for the device
398 enum uclass_id device_get_uclass_id(const struct udevice *dev);
401 * dev_get_uclass_name() - return the uclass name of a device
403 * This checks that dev is not NULL.
405 * @dev: Device to check
406 * @return pointer to the uclass name for the device
408 const char *dev_get_uclass_name(const struct udevice *dev);
411 * device_get_child() - Get the child of a device by index
413 * Returns the numbered child, 0 being the first. This does not use
414 * sequence numbers, only the natural order.
416 * @dev: Parent device to check
417 * @index: Child index
418 * @devp: Returns pointer to device
419 * @return 0 if OK, -ENODEV if no such device, other error if the device fails
422 int device_get_child(const struct udevice *parent, int index,
423 struct udevice **devp);
426 * device_get_child_count() - Get the available child count of a device
428 * Returns the number of children to a device.
430 * @parent: Parent device to check
432 int device_get_child_count(const struct udevice *parent);
435 * device_find_child_by_seq() - Find a child device based on a sequence
437 * This searches for a device with the given seq or req_seq.
439 * For seq, if an active device has this sequence it will be returned.
440 * If there is no such device then this will return -ENODEV.
442 * For req_seq, if a device (whether activated or not) has this req_seq
443 * value, that device will be returned. This is a strong indication that
444 * the device will receive that sequence when activated.
446 * @parent: Parent device
447 * @seq_or_req_seq: Sequence number to find (0=first)
448 * @find_req_seq: true to find req_seq, false to find seq
449 * @devp: Returns pointer to device (there is only one per for each seq).
450 * Set to NULL if none is found
451 * @return 0 if OK, -ve on error
453 int device_find_child_by_seq(const struct udevice *parent, int seq_or_req_seq,
454 bool find_req_seq, struct udevice **devp);
457 * device_get_child_by_seq() - Get a child device based on a sequence
459 * If an active device has this sequence it will be returned. If there is no
460 * such device then this will check for a device that is requesting this
463 * The device is probed to activate it ready for use.
465 * @parent: Parent device
466 * @seq: Sequence number to find (0=first)
467 * @devp: Returns pointer to device (there is only one per for each seq)
468 * Set to NULL if none is found
469 * @return 0 if OK, -ve on error
471 int device_get_child_by_seq(const struct udevice *parent, int seq,
472 struct udevice **devp);
475 * device_find_child_by_of_offset() - Find a child device based on FDT offset
477 * Locates a child device by its device tree offset.
479 * @parent: Parent device
480 * @of_offset: Device tree offset to find
481 * @devp: Returns pointer to device if found, otherwise this is set to NULL
482 * @return 0 if OK, -ve on error
484 int device_find_child_by_of_offset(const struct udevice *parent, int of_offset,
485 struct udevice **devp);
488 * device_get_child_by_of_offset() - Get a child device based on FDT offset
490 * Locates a child device by its device tree offset.
492 * The device is probed to activate it ready for use.
494 * @parent: Parent device
495 * @of_offset: Device tree offset to find
496 * @devp: Returns pointer to device if found, otherwise this is set to NULL
497 * @return 0 if OK, -ve on error
499 int device_get_child_by_of_offset(const struct udevice *parent, int of_offset,
500 struct udevice **devp);
503 * device_find_global_by_ofnode() - Get a device based on ofnode
505 * Locates a device by its device tree ofnode, searching globally throughout
506 * the all driver model devices.
508 * The device is NOT probed
510 * @node: Device tree ofnode to find
511 * @devp: Returns pointer to device if found, otherwise this is set to NULL
512 * @return 0 if OK, -ve on error
515 int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
518 * device_get_global_by_ofnode() - Get a device based on ofnode
520 * Locates a device by its device tree ofnode, searching globally throughout
521 * the all driver model devices.
523 * The device is probed to activate it ready for use.
525 * @node: Device tree ofnode to find
526 * @devp: Returns pointer to device if found, otherwise this is set to NULL
527 * @return 0 if OK, -ve on error
529 int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
532 * device_find_first_child() - Find the first child of a device
534 * @parent: Parent device to search
535 * @devp: Returns first child device, or NULL if none
538 int device_find_first_child(const struct udevice *parent,
539 struct udevice **devp);
542 * device_find_next_child() - Find the next child of a device
544 * @devp: Pointer to previous child device on entry. Returns pointer to next
545 * child device, or NULL if none
548 int device_find_next_child(struct udevice **devp);
551 * device_find_first_inactive_child() - Find the first inactive child
553 * This is used to locate an existing child of a device which is of a given
556 * The device is NOT probed
558 * @parent: Parent device to search
559 * @uclass_id: Uclass to look for
560 * @devp: Returns device found, if any
561 * @return 0 if found, else -ENODEV
563 int device_find_first_inactive_child(const struct udevice *parent,
564 enum uclass_id uclass_id,
565 struct udevice **devp);
568 * device_find_first_child_by_uclass() - Find the first child of a device in uc
570 * @parent: Parent device to search
571 * @uclass_id: Uclass to look for
572 * @devp: Returns first child device in that uclass, if any
573 * @return 0 if found, else -ENODEV
575 int device_find_first_child_by_uclass(const struct udevice *parent,
576 enum uclass_id uclass_id,
577 struct udevice **devp);
580 * device_find_child_by_name() - Find a child by device name
582 * @parent: Parent device to search
583 * @name: Name to look for
584 * @devp: Returns device found, if any
585 * @return 0 if found, else -ENODEV
587 int device_find_child_by_name(const struct udevice *parent, const char *name,
588 struct udevice **devp);
591 * device_first_child_ofdata_err() - Find the first child and reads its platdata
593 * The ofdata_to_platdata() method is called on the child before it is returned,
594 * but the child is not probed.
596 * @parent: Parent to check
597 * @devp: Returns child that was found, if any
598 * @return 0 on success, -ENODEV if no children, other -ve on error
600 int device_first_child_ofdata_err(struct udevice *parent,
601 struct udevice **devp);
604 * device_next_child_ofdata_err() - Find the next child and read its platdata
606 * The ofdata_to_platdata() method is called on the child before it is returned,
607 * but the child is not probed.
609 * @devp: On entry, points to the previous child; on exit returns the child that
611 * @return 0 on success, -ENODEV if no children, other -ve on error
613 int device_next_child_ofdata_err(struct udevice **devp);
616 * device_first_child_err() - Get the first child of a device
618 * The device returned is probed if necessary, and ready for use
620 * @parent: Parent device to search
621 * @devp: Returns device found, if any
622 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
624 int device_first_child_err(struct udevice *parent, struct udevice **devp);
627 * device_next_child_err() - Get the next child of a parent device
629 * The device returned is probed if necessary, and ready for use
631 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
632 * to the next sibling if no error occurred
633 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
635 int device_next_child_err(struct udevice **devp);
638 * device_has_children() - check if a device has any children
640 * @dev: Device to check
641 * @return true if the device has one or more children
643 bool device_has_children(const struct udevice *dev);
646 * device_has_active_children() - check if a device has any active children
648 * @dev: Device to check
649 * @return true if the device has one or more children and at least one of
650 * them is active (probed).
652 bool device_has_active_children(const struct udevice *dev);
655 * device_is_last_sibling() - check if a device is the last sibling
657 * This function can be useful for display purposes, when special action needs
658 * to be taken when displaying the last sibling. This can happen when a tree
659 * view of devices is being displayed.
661 * @dev: Device to check
662 * @return true if there are no more siblings after this one - i.e. is it
665 bool device_is_last_sibling(const struct udevice *dev);
668 * device_set_name() - set the name of a device
670 * This must be called in the device's bind() method and no later. Normally
671 * this is unnecessary but for probed devices which don't get a useful name
672 * this function can be helpful.
674 * The name is allocated and will be freed automatically when the device is
677 * @dev: Device to update
678 * @name: New name (this string is allocated new memory and attached to
680 * @return 0 if OK, -ENOMEM if there is not enough memory to allocate the
683 int device_set_name(struct udevice *dev, const char *name);
686 * device_set_name_alloced() - note that a device name is allocated
688 * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
689 * unbound the name will be freed. This avoids memory leaks.
691 * @dev: Device to update
693 void device_set_name_alloced(struct udevice *dev);
696 * device_is_compatible() - check if the device is compatible with the compat
698 * This allows to check whether the device is comaptible with the compat.
700 * @dev: udevice pointer for which compatible needs to be verified.
701 * @compat: Compatible string which needs to verified in the given
703 * @return true if OK, false if the compatible is not found
705 bool device_is_compatible(const struct udevice *dev, const char *compat);
708 * of_machine_is_compatible() - check if the machine is compatible with
711 * This allows to check whether the machine is comaptible with the compat.
713 * @compat: Compatible string which needs to verified
714 * @return true if OK, false if the compatible is not found
716 bool of_machine_is_compatible(const char *compat);
719 * dev_disable_by_path() - Disable a device given its device tree path
721 * @path: The device tree path identifying the device to be disabled
722 * @return 0 on success, -ve on error
724 int dev_disable_by_path(const char *path);
727 * dev_enable_by_path() - Enable a device given its device tree path
729 * @path: The device tree path identifying the device to be enabled
730 * @return 0 on success, -ve on error
732 int dev_enable_by_path(const char *path);
735 * device_is_on_pci_bus - Test if a device is on a PCI bus
737 * @dev: device to test
738 * @return: true if it is on a PCI bus, false otherwise
740 static inline bool device_is_on_pci_bus(const struct udevice *dev)
742 return device_get_uclass_id(dev->parent) == UCLASS_PCI;
746 * device_foreach_child_safe() - iterate through child devices safely
748 * This allows the @pos child to be removed in the loop if required.
750 * @pos: struct udevice * for the current device
751 * @next: struct udevice * for the next device
752 * @parent: parent device to scan
754 #define device_foreach_child_safe(pos, next, parent) \
755 list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
758 * device_foreach_child() - iterate through child devices
760 * @pos: struct udevice * for the current device
761 * @parent: parent device to scan
763 #define device_foreach_child(pos, parent) \
764 list_for_each_entry(pos, &parent->child_head, sibling_node)
767 * device_foreach_child_ofdata_to_platdata() - iterate through children
769 * This stops when it gets an error, with @pos set to the device that failed to
772 * This creates a for() loop which works through the available children of
773 * a device in order from start to end. Device ofdata is read by calling
774 * device_ofdata_to_platdata() on each one. The devices are not probed.
776 * @pos: struct udevice * for the current device
777 * @parent: parent device to scan
779 #define device_foreach_child_ofdata_to_platdata(pos, parent) \
780 for (int _ret = device_first_child_ofdata_err(parent, &dev); !_ret; \
781 _ret = device_next_child_ofdata_err(&dev))
784 * device_foreach_child_probe() - iterate through children, probing them
786 * This creates a for() loop which works through the available children of
787 * a device in order from start to end. Devices are probed if necessary,
790 * This stops when it gets an error, with @pos set to the device that failed to
793 * @pos: struct udevice * for the current device
794 * @parent: parent device to scan
796 #define device_foreach_child_probe(pos, parent) \
797 for (int _ret = device_first_child_err(parent, &dev); !_ret; \
798 _ret = device_next_child_err(&dev))
801 * dm_scan_fdt_dev() - Bind child device in a the device tree
803 * This handles device which have sub-nodes in the device tree. It scans all
804 * sub-nodes and binds drivers for each node where a driver can be found.
806 * If this is called prior to relocation, only pre-relocation devices will be
807 * bound (those marked with u-boot,dm-pre-reloc in the device tree, or where
808 * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
811 * @dev: Device to scan
812 * @return 0 if OK, -ve on error
814 int dm_scan_fdt_dev(struct udevice *dev);