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 plat */
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_plat */
33 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
35 /* DM is responsible for allocating and freeing uclass_plat */
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 plat 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_LEAVE_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,
96 /* Don't power down any attached power domains */
97 DM_REMOVE_NO_PD = 1 << 1,
101 * struct udevice - An instance of a driver
103 * This holds information about a device, which is a driver bound to a
104 * particular port or peripheral (essentially a driver instance).
106 * A device will come into existence through a 'bind' call, either due to
107 * a U_BOOT_DRVINFO() macro (in which case plat is non-NULL) or a node
108 * in the device tree (in which case of_offset is >= 0). In the latter case
109 * we translate the device tree information into plat in a function
110 * implemented by the driver of_to_plat method (called just before the
111 * probe method if the device has a device tree node.
113 * All three of plat, priv and uclass_priv can be allocated by the
114 * driver, or you can use the auto members of struct driver and
115 * struct uclass_driver to have driver model do this automatically.
117 * @driver: The driver used by this device
118 * @name: Name of device, typically the FDT node name
119 * @plat_: Configuration data for this device (do not access outside driver
121 * @parent_plat_: The parent bus's configuration data for this device (do not
122 * access outside driver model)
123 * @uclass_plat_: The uclass's configuration data for this device (do not access
124 * outside driver model)
125 * @driver_data: Driver data word for the entry that matched this device with
127 * @parent: Parent of this device, or NULL for the top level device
128 * @priv_: Private data for this device (do not access outside driver model)
129 * @uclass: Pointer to uclass for this device
130 * @uclass_priv_: The uclass's private data for this device (do not access
131 * outside driver model)
132 * @parent_priv_: The parent's private data for this device (do not access
133 * outside driver model)
134 * @uclass_node: Used by uclass to link its devices
135 * @child_head: List of children of this device
136 * @sibling_node: Next device in list of all devices
137 * @flags_: Flags for this device DM_FLAG_... (do not access outside driver
139 * @seq_: Allocated sequence number for this device (-1 = none). This is set up
140 * when the device is bound and is unique within the device's uclass. If the
141 * device has an alias in the devicetree then that is used to set the sequence
142 * number. Otherwise, the next available number is used. Sequence numbers are
143 * used by certain commands that need device to be numbered (e.g. 'mmc dev').
144 * (do not access outside driver model)
145 * @node_: Reference to device tree node for this device (do not access outside
147 * @devres_head: List of memory allocations associated with this device.
148 * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
149 * add to this list. Memory so-allocated will be freed
150 * automatically when the device is removed / unbound
153 const struct driver *driver;
159 struct udevice *parent;
161 struct uclass *uclass;
164 struct list_head uclass_node;
165 struct list_head child_head;
166 struct list_head sibling_node;
169 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
173 struct list_head devres_head;
177 /* Maximum sequence number supported */
178 #define DM_MAX_SEQ 999
180 /* Returns the operations for a device */
181 #define device_get_ops(dev) (dev->driver->ops)
183 static inline u32 dev_get_flags(const struct udevice *dev)
188 static inline void dev_or_flags(struct udevice *dev, u32 or)
193 static inline void dev_bic_flags(struct udevice *dev, u32 bic)
199 * dev_ofnode() - get the DT node reference associated with a udevice
201 * @dev: device to check
202 * @return reference of the the device's DT node
204 static inline ofnode dev_ofnode(const struct udevice *dev)
206 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
209 return ofnode_null();
213 /* Returns non-zero if the device is active (probed and not removed) */
214 #define device_active(dev) (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
216 static inline int dev_of_offset(const struct udevice *dev)
218 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
219 return ofnode_to_offset(dev_ofnode(dev));
225 static inline bool dev_has_ofnode(const struct udevice *dev)
227 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
228 return ofnode_valid(dev_ofnode(dev));
234 static inline void dev_set_ofnode(struct udevice *dev, ofnode node)
236 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
241 static inline int dev_seq(const struct udevice *dev)
247 * struct udevice_id - Lists the compatible strings supported by a driver
248 * @compatible: Compatible string
249 * @data: Data for this compatible string
252 const char *compatible;
256 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
257 #define of_match_ptr(_ptr) (_ptr)
259 #define of_match_ptr(_ptr) NULL
260 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
263 * struct driver - A driver for a feature or peripheral
265 * This holds methods for setting up a new device, and also removing it.
266 * The device needs information to set itself up - this is provided either
267 * by plat or a device tree node (which we find by looking up
268 * matching compatible strings with of_match).
270 * Drivers all belong to a uclass, representing a class of devices of the
271 * same type. Common elements of the drivers can be implemented in the uclass,
272 * or the uclass can provide a consistent interface to the drivers within
276 * @id: Identifies the uclass we belong to
277 * @of_match: List of compatible strings to match, and any identifying data
279 * @bind: Called to bind a device to its driver
280 * @probe: Called to probe a device, i.e. activate it
281 * @remove: Called to remove a device, i.e. de-activate it
282 * @unbind: Called to unbind a device from its driver
283 * @of_to_plat: Called before probe to decode device tree data
284 * @child_post_bind: Called after a new child has been bound
285 * @child_pre_probe: Called before a child device is probed. The device has
286 * memory allocated but it has not yet been probed.
287 * @child_post_remove: Called after a child device is removed. The device
288 * has memory allocated but its device_remove() method has been called.
289 * @priv_auto: If non-zero this is the size of the private data
290 * to be allocated in the device's ->priv pointer. If zero, then the driver
291 * is responsible for allocating any data required.
292 * @plat_auto: If non-zero this is the size of the
293 * platform data to be allocated in the device's ->plat pointer.
294 * This is typically only useful for device-tree-aware drivers (those with
295 * an of_match), since drivers which use plat will have the data
296 * provided in the U_BOOT_DRVINFO() instantiation.
297 * @per_child_auto: Each device can hold private data owned by
298 * its parent. If required this will be automatically allocated if this
300 * @per_child_plat_auto: A bus likes to store information about
301 * its children. If non-zero this is the size of this data, to be allocated
302 * in the child's parent_plat pointer.
303 * @ops: Driver-specific operations. This is typically a list of function
304 * pointers defined by the driver, to implement driver functions required by
306 * @flags: driver flags - see DM_FLAGS_...
307 * @acpi_ops: Advanced Configuration and Power Interface (ACPI) operations,
308 * allowing the device to add things to the ACPI tables passed to Linux
313 const struct udevice_id *of_match;
314 int (*bind)(struct udevice *dev);
315 int (*probe)(struct udevice *dev);
316 int (*remove)(struct udevice *dev);
317 int (*unbind)(struct udevice *dev);
318 int (*of_to_plat)(struct udevice *dev);
319 int (*child_post_bind)(struct udevice *dev);
320 int (*child_pre_probe)(struct udevice *dev);
321 int (*child_post_remove)(struct udevice *dev);
325 int per_child_plat_auto;
326 const void *ops; /* driver-specific operations */
328 #if CONFIG_IS_ENABLED(ACPIGEN)
329 struct acpi_ops *acpi_ops;
333 /* Declare a new U-Boot driver */
334 #define U_BOOT_DRIVER(__name) \
335 ll_entry_declare(struct driver, __name, driver)
337 /* Get a pointer to a given driver */
338 #define DM_DRIVER_GET(__name) \
339 ll_entry_get(struct driver, __name, driver)
342 * Declare a macro to state a alias for a driver name. This macro will
343 * produce no code but its information will be parsed by tools like
346 #define DM_DRIVER_ALIAS(__name, __alias)
349 * dev_get_plat() - Get the platform data for a device
351 * This checks that dev is not NULL, but no other checks for now
353 * @dev Device to check
354 * @return platform data, or NULL if none
356 void *dev_get_plat(const struct udevice *dev);
359 * dev_get_parent_plat() - Get the parent platform data for a device
361 * This checks that dev is not NULL, but no other checks for now
363 * @dev Device to check
364 * @return parent's platform data, or NULL if none
366 void *dev_get_parent_plat(const struct udevice *dev);
369 * dev_get_uclass_plat() - Get the uclass platform data for a device
371 * This checks that dev is not NULL, but no other checks for now
373 * @dev Device to check
374 * @return uclass's platform data, or NULL if none
376 void *dev_get_uclass_plat(const struct udevice *dev);
379 * dev_get_priv() - Get the private data for a device
381 * This checks that dev is not NULL, but no other checks for now
383 * @dev Device to check
384 * @return private data, or NULL if none
386 void *dev_get_priv(const struct udevice *dev);
389 * dev_get_parent_priv() - Get the parent private data for a device
391 * The parent private data is data stored in the device but owned by the
392 * parent. For example, a USB device may have parent data which contains
393 * information about how to talk to the device over USB.
395 * This checks that dev is not NULL, but no other checks for now
397 * @dev Device to check
398 * @return parent data, or NULL if none
400 void *dev_get_parent_priv(const struct udevice *dev);
403 * dev_get_uclass_priv() - Get the private uclass data for a device
405 * This checks that dev is not NULL, but no other checks for now
407 * @dev Device to check
408 * @return private uclass data for this device, or NULL if none
410 void *dev_get_uclass_priv(const struct udevice *dev);
413 * struct dev_get_parent() - Get the parent of a device
415 * @child: Child to check
416 * @return parent of child, or NULL if this is the root device
418 struct udevice *dev_get_parent(const struct udevice *child);
421 * dev_get_driver_data() - get the driver data used to bind a device
423 * When a device is bound using a device tree node, it matches a
424 * particular compatible string in struct udevice_id. This function
425 * returns the associated data value for that compatible string. This is
426 * the 'data' field in struct udevice_id.
428 * As an example, consider this structure:
429 * static const struct udevice_id tegra_i2c_ids[] = {
430 * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
431 * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
432 * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
436 * When driver model finds a driver for this it will store the 'data' value
437 * corresponding to the compatible string it matches. This function returns
438 * that value. This allows the driver to handle several variants of a device.
440 * For USB devices, this is the driver_info field in struct usb_device_id.
442 * @dev: Device to check
443 * @return driver data (0 if none is provided)
445 ulong dev_get_driver_data(const struct udevice *dev);
448 * dev_get_driver_ops() - get the device's driver's operations
450 * This checks that dev is not NULL, and returns the pointer to device's
451 * driver's operations.
453 * @dev: Device to check
454 * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
456 const void *dev_get_driver_ops(const struct udevice *dev);
459 * device_get_uclass_id() - return the uclass ID of a device
461 * @dev: Device to check
462 * @return uclass ID for the device
464 enum uclass_id device_get_uclass_id(const struct udevice *dev);
467 * dev_get_uclass_name() - return the uclass name of a device
469 * This checks that dev is not NULL.
471 * @dev: Device to check
472 * @return pointer to the uclass name for the device
474 const char *dev_get_uclass_name(const struct udevice *dev);
477 * device_get_child() - Get the child of a device by index
479 * Returns the numbered child, 0 being the first. This does not use
480 * sequence numbers, only the natural order.
482 * @dev: Parent device to check
483 * @index: Child index
484 * @devp: Returns pointer to device
485 * @return 0 if OK, -ENODEV if no such device, other error if the device fails
488 int device_get_child(const struct udevice *parent, int index,
489 struct udevice **devp);
492 * device_get_child_count() - Get the available child count of a device
494 * Returns the number of children to a device.
496 * @parent: Parent device to check
498 int device_get_child_count(const struct udevice *parent);
501 * device_find_child_by_seq() - Find a child device based on a sequence
503 * This searches for a device with the given seq.
505 * @parent: Parent device
506 * @seq: Sequence number to find (0=first)
507 * @devp: Returns pointer to device (there is only one per for each seq).
508 * Set to NULL if none is found
509 * @return 0 if OK, -ENODEV if not found
511 int device_find_child_by_seq(const struct udevice *parent, int seq,
512 struct udevice **devp);
515 * device_get_child_by_seq() - Get a child device based on a sequence
517 * If an active device has this sequence it will be returned. If there is no
518 * such device then this will check for a device that is requesting this
521 * The device is probed to activate it ready for use.
523 * @parent: Parent device
524 * @seq: Sequence number to find (0=first)
525 * @devp: Returns pointer to device (there is only one per for each seq)
526 * Set to NULL if none is found
527 * @return 0 if OK, -ve on error
529 int device_get_child_by_seq(const struct udevice *parent, int seq,
530 struct udevice **devp);
533 * device_find_child_by_of_offset() - Find a child device based on FDT offset
535 * Locates a child device by its device tree offset.
537 * @parent: Parent device
538 * @of_offset: Device tree offset to find
539 * @devp: Returns pointer to device if found, otherwise this is set to NULL
540 * @return 0 if OK, -ve on error
542 int device_find_child_by_of_offset(const struct udevice *parent, int of_offset,
543 struct udevice **devp);
546 * device_get_child_by_of_offset() - Get a child device based on FDT offset
548 * Locates a child device by its device tree offset.
550 * The device is probed to activate it ready for use.
552 * @parent: Parent device
553 * @of_offset: Device tree offset to find
554 * @devp: Returns pointer to device if found, otherwise this is set to NULL
555 * @return 0 if OK, -ve on error
557 int device_get_child_by_of_offset(const struct udevice *parent, int of_offset,
558 struct udevice **devp);
561 * device_find_global_by_ofnode() - Get a device based on ofnode
563 * Locates a device by its device tree ofnode, searching globally throughout
564 * the all driver model devices.
566 * The device is NOT probed
568 * @node: Device tree ofnode to find
569 * @devp: Returns pointer to device if found, otherwise this is set to NULL
570 * @return 0 if OK, -ve on error
573 int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
576 * device_get_global_by_ofnode() - Get a device based on ofnode
578 * Locates a device by its device tree ofnode, searching globally throughout
579 * the all driver model devices.
581 * The device is probed to activate it ready for use.
583 * @node: Device tree ofnode to find
584 * @devp: Returns pointer to device if found, otherwise this is set to NULL
585 * @return 0 if OK, -ve on error
587 int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
590 * device_get_by_driver_info() - Get a device based on driver_info
592 * Locates a device by its struct driver_info, by using its reference which
593 * is updated during the bind process.
595 * The device is probed to activate it ready for use.
597 * @info: Struct driver_info
598 * @devp: Returns pointer to device if found, otherwise this is set to NULL
599 * @return 0 if OK, -ve on error
601 int device_get_by_driver_info(const struct driver_info *info,
602 struct udevice **devp);
605 * device_get_by_driver_info_idx() - Get a device based on driver_info index
607 * Locates a device by its struct driver_info, by using its index number which
608 * is written into the idx field of struct phandle_1_arg, etc.
610 * The device is probed to activate it ready for use.
612 * @idx: Index number of the driver_info structure (0=first)
613 * @devp: Returns pointer to device if found, otherwise this is set to NULL
614 * @return 0 if OK, -ve on error
616 int device_get_by_driver_info_idx(uint idx, struct udevice **devp);
619 * device_find_first_child() - Find the first child of a device
621 * @parent: Parent device to search
622 * @devp: Returns first child device, or NULL if none
625 int device_find_first_child(const struct udevice *parent,
626 struct udevice **devp);
629 * device_find_next_child() - Find the next child of a device
631 * @devp: Pointer to previous child device on entry. Returns pointer to next
632 * child device, or NULL if none
635 int device_find_next_child(struct udevice **devp);
638 * device_find_first_inactive_child() - Find the first inactive child
640 * This is used to locate an existing child of a device which is of a given
643 * The device is NOT probed
645 * @parent: Parent device to search
646 * @uclass_id: Uclass to look for
647 * @devp: Returns device found, if any
648 * @return 0 if found, else -ENODEV
650 int device_find_first_inactive_child(const struct udevice *parent,
651 enum uclass_id uclass_id,
652 struct udevice **devp);
655 * device_find_first_child_by_uclass() - Find the first child of a device in uc
657 * @parent: Parent device to search
658 * @uclass_id: Uclass to look for
659 * @devp: Returns first child device in that uclass, if any
660 * @return 0 if found, else -ENODEV
662 int device_find_first_child_by_uclass(const struct udevice *parent,
663 enum uclass_id uclass_id,
664 struct udevice **devp);
667 * device_find_child_by_name() - Find a child by device name
669 * @parent: Parent device to search
670 * @name: Name to look for
671 * @devp: Returns device found, if any
672 * @return 0 if found, else -ENODEV
674 int device_find_child_by_name(const struct udevice *parent, const char *name,
675 struct udevice **devp);
678 * device_first_child_ofdata_err() - Find the first child and reads its plat
680 * The of_to_plat() method is called on the child before it is returned,
681 * but the child is not probed.
683 * @parent: Parent to check
684 * @devp: Returns child that was found, if any
685 * @return 0 on success, -ENODEV if no children, other -ve on error
687 int device_first_child_ofdata_err(struct udevice *parent,
688 struct udevice **devp);
691 * device_next_child_ofdata_err() - Find the next child and read its plat
693 * The of_to_plat() method is called on the child before it is returned,
694 * but the child is not probed.
696 * @devp: On entry, points to the previous child; on exit returns the child that
698 * @return 0 on success, -ENODEV if no children, other -ve on error
700 int device_next_child_ofdata_err(struct udevice **devp);
703 * device_first_child_err() - Get the first child of a device
705 * The device returned is probed if necessary, and ready for use
707 * @parent: Parent device to search
708 * @devp: Returns device found, if any
709 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
711 int device_first_child_err(struct udevice *parent, struct udevice **devp);
714 * device_next_child_err() - Get the next child of a parent device
716 * The device returned is probed if necessary, and ready for use
718 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
719 * to the next sibling if no error occurred
720 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
722 int device_next_child_err(struct udevice **devp);
725 * device_has_children() - check if a device has any children
727 * @dev: Device to check
728 * @return true if the device has one or more children
730 bool device_has_children(const struct udevice *dev);
733 * device_has_active_children() - check if a device has any active children
735 * @dev: Device to check
736 * @return true if the device has one or more children and at least one of
737 * them is active (probed).
739 bool device_has_active_children(const struct udevice *dev);
742 * device_is_last_sibling() - check if a device is the last sibling
744 * This function can be useful for display purposes, when special action needs
745 * to be taken when displaying the last sibling. This can happen when a tree
746 * view of devices is being displayed.
748 * @dev: Device to check
749 * @return true if there are no more siblings after this one - i.e. is it
752 bool device_is_last_sibling(const struct udevice *dev);
755 * device_set_name() - set the name of a device
757 * This must be called in the device's bind() method and no later. Normally
758 * this is unnecessary but for probed devices which don't get a useful name
759 * this function can be helpful.
761 * The name is allocated and will be freed automatically when the device is
764 * @dev: Device to update
765 * @name: New name (this string is allocated new memory and attached to
767 * @return 0 if OK, -ENOMEM if there is not enough memory to allocate the
770 int device_set_name(struct udevice *dev, const char *name);
773 * device_set_name_alloced() - note that a device name is allocated
775 * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
776 * unbound the name will be freed. This avoids memory leaks.
778 * @dev: Device to update
780 void device_set_name_alloced(struct udevice *dev);
783 * device_is_compatible() - check if the device is compatible with the compat
785 * This allows to check whether the device is comaptible with the compat.
787 * @dev: udevice pointer for which compatible needs to be verified.
788 * @compat: Compatible string which needs to verified in the given
790 * @return true if OK, false if the compatible is not found
792 bool device_is_compatible(const struct udevice *dev, const char *compat);
795 * of_machine_is_compatible() - check if the machine is compatible with
798 * This allows to check whether the machine is comaptible with the compat.
800 * @compat: Compatible string which needs to verified
801 * @return true if OK, false if the compatible is not found
803 bool of_machine_is_compatible(const char *compat);
806 * dev_disable_by_path() - Disable a device given its device tree path
808 * @path: The device tree path identifying the device to be disabled
809 * @return 0 on success, -ve on error
811 int dev_disable_by_path(const char *path);
814 * dev_enable_by_path() - Enable a device given its device tree path
816 * @path: The device tree path identifying the device to be enabled
817 * @return 0 on success, -ve on error
819 int dev_enable_by_path(const char *path);
822 * device_is_on_pci_bus - Test if a device is on a PCI bus
824 * @dev: device to test
825 * @return: true if it is on a PCI bus, false otherwise
827 static inline bool device_is_on_pci_bus(const struct udevice *dev)
829 return dev->parent && device_get_uclass_id(dev->parent) == UCLASS_PCI;
833 * device_foreach_child_safe() - iterate through child devices safely
835 * This allows the @pos child to be removed in the loop if required.
837 * @pos: struct udevice * for the current device
838 * @next: struct udevice * for the next device
839 * @parent: parent device to scan
841 #define device_foreach_child_safe(pos, next, parent) \
842 list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
845 * device_foreach_child() - iterate through child devices
847 * @pos: struct udevice * for the current device
848 * @parent: parent device to scan
850 #define device_foreach_child(pos, parent) \
851 list_for_each_entry(pos, &parent->child_head, sibling_node)
854 * device_foreach_child_of_to_plat() - iterate through children
856 * This stops when it gets an error, with @pos set to the device that failed to
859 * This creates a for() loop which works through the available children of
860 * a device in order from start to end. Device ofdata is read by calling
861 * device_of_to_plat() on each one. The devices are not probed.
863 * @pos: struct udevice * for the current device
864 * @parent: parent device to scan
866 #define device_foreach_child_of_to_plat(pos, parent) \
867 for (int _ret = device_first_child_ofdata_err(parent, &dev); !_ret; \
868 _ret = device_next_child_ofdata_err(&dev))
871 * device_foreach_child_probe() - iterate through children, probing them
873 * This creates a for() loop which works through the available children of
874 * a device in order from start to end. Devices are probed if necessary,
877 * This stops when it gets an error, with @pos set to the device that failed to
880 * @pos: struct udevice * for the current device
881 * @parent: parent device to scan
883 #define device_foreach_child_probe(pos, parent) \
884 for (int _ret = device_first_child_err(parent, &dev); !_ret; \
885 _ret = device_next_child_err(&dev))
888 * dm_scan_fdt_dev() - Bind child device in the device tree
890 * This handles device which have sub-nodes in the device tree. It scans all
891 * sub-nodes and binds drivers for each node where a driver can be found.
893 * If this is called prior to relocation, only pre-relocation devices will be
894 * bound (those marked with u-boot,dm-pre-reloc in the device tree, or where
895 * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
898 * @dev: Device to scan
899 * @return 0 if OK, -ve on error
901 int dm_scan_fdt_dev(struct udevice *dev);