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_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,
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_DEVICE() 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_alloc_size 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 * @node: Reference to device tree node for this device
126 * @driver_data: Driver data word for the entry that matched this device with
128 * @parent: Parent of this device, or NULL for the top level device
129 * @priv_: Private data for this device (do not access outside driver model)
130 * @uclass: Pointer to uclass for this device
131 * @uclass_priv_: The uclass's private data for this device (do not access
132 * outside driver model)
133 * @parent_priv_: The parent's private data for this device (do not access
134 * outside driver model)
135 * @uclass_node: Used by uclass to link its devices
136 * @child_head: List of children of this device
137 * @sibling_node: Next device in list of all devices
138 * @flags_: Flags for this device DM_FLAG_... (do not access outside driver
140 * @seq_: Allocated sequence number for this device (-1 = none). This is set up
141 * when the device is bound and is unique within the device's uclass. If the
142 * device has an alias in the devicetree then that is used to set the sequence
143 * number. Otherwise, the next available number is used. Sequence numbers are
144 * used by certain commands that need device to be numbered (e.g. 'mmc dev').
145 * (do not access outside driver model)
146 * @devres_head: List of memory allocations associated with this device.
147 * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
148 * add to this list. Memory so-allocated will be freed
149 * automatically when the device is removed / unbound
152 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;
170 struct list_head devres_head;
174 /* Maximum sequence number supported */
175 #define DM_MAX_SEQ 999
177 /* Returns the operations for a device */
178 #define device_get_ops(dev) (dev->driver->ops)
180 static inline u32 dev_get_flags(const struct udevice *dev)
185 static inline void dev_or_flags(struct udevice *dev, u32 or)
190 static inline void dev_bic_flags(struct udevice *dev, u32 bic)
196 * dev_ofnode() - get the DT node reference associated with a udevice
198 * @dev: device to check
199 * @return reference of the the device's DT node
201 static inline ofnode dev_ofnode(const struct udevice *dev)
203 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
206 return ofnode_null();
210 /* Returns non-zero if the device is active (probed and not removed) */
211 #define device_active(dev) (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
213 static inline int dev_of_offset(const struct udevice *dev)
215 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
216 return ofnode_to_offset(dev_ofnode(dev));
222 static inline bool dev_has_ofnode(const struct udevice *dev)
224 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
225 return ofnode_valid(dev_ofnode(dev));
231 static inline void dev_set_ofnode(struct udevice *dev, ofnode node)
233 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
238 static inline int dev_seq(const struct udevice *dev)
244 * struct udevice_id - Lists the compatible strings supported by a driver
245 * @compatible: Compatible string
246 * @data: Data for this compatible string
249 const char *compatible;
253 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
254 #define of_match_ptr(_ptr) (_ptr)
256 #define of_match_ptr(_ptr) NULL
257 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
260 * struct driver - A driver for a feature or peripheral
262 * This holds methods for setting up a new device, and also removing it.
263 * The device needs information to set itself up - this is provided either
264 * by plat or a device tree node (which we find by looking up
265 * matching compatible strings with of_match).
267 * Drivers all belong to a uclass, representing a class of devices of the
268 * same type. Common elements of the drivers can be implemented in the uclass,
269 * or the uclass can provide a consistent interface to the drivers within
273 * @id: Identifies the uclass we belong to
274 * @of_match: List of compatible strings to match, and any identifying data
276 * @bind: Called to bind a device to its driver
277 * @probe: Called to probe a device, i.e. activate it
278 * @remove: Called to remove a device, i.e. de-activate it
279 * @unbind: Called to unbind a device from its driver
280 * @of_to_plat: Called before probe to decode device tree data
281 * @child_post_bind: Called after a new child has been bound
282 * @child_pre_probe: Called before a child device is probed. The device has
283 * memory allocated but it has not yet been probed.
284 * @child_post_remove: Called after a child device is removed. The device
285 * has memory allocated but its device_remove() method has been called.
286 * @priv_auto: If non-zero this is the size of the private data
287 * to be allocated in the device's ->priv pointer. If zero, then the driver
288 * is responsible for allocating any data required.
289 * @plat_auto: If non-zero this is the size of the
290 * platform data to be allocated in the device's ->plat pointer.
291 * This is typically only useful for device-tree-aware drivers (those with
292 * an of_match), since drivers which use plat will have the data
293 * provided in the U_BOOT_DEVICE() instantiation.
294 * @per_child_auto: Each device can hold private data owned by
295 * its parent. If required this will be automatically allocated if this
297 * @per_child_plat_auto: A bus likes to store information about
298 * its children. If non-zero this is the size of this data, to be allocated
299 * in the child's parent_plat pointer.
300 * @ops: Driver-specific operations. This is typically a list of function
301 * pointers defined by the driver, to implement driver functions required by
303 * @flags: driver flags - see DM_FLAGS_...
304 * @acpi_ops: Advanced Configuration and Power Interface (ACPI) operations,
305 * allowing the device to add things to the ACPI tables passed to Linux
310 const struct udevice_id *of_match;
311 int (*bind)(struct udevice *dev);
312 int (*probe)(struct udevice *dev);
313 int (*remove)(struct udevice *dev);
314 int (*unbind)(struct udevice *dev);
315 int (*of_to_plat)(struct udevice *dev);
316 int (*child_post_bind)(struct udevice *dev);
317 int (*child_pre_probe)(struct udevice *dev);
318 int (*child_post_remove)(struct udevice *dev);
322 int per_child_plat_auto;
323 const void *ops; /* driver-specific operations */
325 #if CONFIG_IS_ENABLED(ACPIGEN)
326 struct acpi_ops *acpi_ops;
330 /* Declare a new U-Boot driver */
331 #define U_BOOT_DRIVER(__name) \
332 ll_entry_declare(struct driver, __name, driver)
334 /* Get a pointer to a given driver */
335 #define DM_GET_DRIVER(__name) \
336 ll_entry_get(struct driver, __name, driver)
339 * Declare a macro to state a alias for a driver name. This macro will
340 * produce no code but its information will be parsed by tools like
343 #define U_BOOT_DRIVER_ALIAS(__name, __alias)
346 * dev_get_plat() - Get the platform data for a device
348 * This checks that dev is not NULL, but no other checks for now
350 * @dev Device to check
351 * @return platform data, or NULL if none
353 void *dev_get_plat(const struct udevice *dev);
356 * dev_get_parent_plat() - Get the parent platform data for a device
358 * This checks that dev is not NULL, but no other checks for now
360 * @dev Device to check
361 * @return parent's platform data, or NULL if none
363 void *dev_get_parent_plat(const struct udevice *dev);
366 * dev_get_uclass_plat() - Get the uclass platform data for a device
368 * This checks that dev is not NULL, but no other checks for now
370 * @dev Device to check
371 * @return uclass's platform data, or NULL if none
373 void *dev_get_uclass_plat(const struct udevice *dev);
376 * dev_get_priv() - Get the private data for a device
378 * This checks that dev is not NULL, but no other checks for now
380 * @dev Device to check
381 * @return private data, or NULL if none
383 void *dev_get_priv(const struct udevice *dev);
386 * dev_get_parent_priv() - Get the parent private data for a device
388 * The parent private data is data stored in the device but owned by the
389 * parent. For example, a USB device may have parent data which contains
390 * information about how to talk to the device over USB.
392 * This checks that dev is not NULL, but no other checks for now
394 * @dev Device to check
395 * @return parent data, or NULL if none
397 void *dev_get_parent_priv(const struct udevice *dev);
400 * dev_get_uclass_priv() - Get the private uclass data for a device
402 * This checks that dev is not NULL, but no other checks for now
404 * @dev Device to check
405 * @return private uclass data for this device, or NULL if none
407 void *dev_get_uclass_priv(const struct udevice *dev);
410 * struct dev_get_parent() - Get the parent of a device
412 * @child: Child to check
413 * @return parent of child, or NULL if this is the root device
415 struct udevice *dev_get_parent(const struct udevice *child);
418 * dev_get_driver_data() - get the driver data used to bind a device
420 * When a device is bound using a device tree node, it matches a
421 * particular compatible string in struct udevice_id. This function
422 * returns the associated data value for that compatible string. This is
423 * the 'data' field in struct udevice_id.
425 * As an example, consider this structure:
426 * static const struct udevice_id tegra_i2c_ids[] = {
427 * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
428 * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
429 * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
433 * When driver model finds a driver for this it will store the 'data' value
434 * corresponding to the compatible string it matches. This function returns
435 * that value. This allows the driver to handle several variants of a device.
437 * For USB devices, this is the driver_info field in struct usb_device_id.
439 * @dev: Device to check
440 * @return driver data (0 if none is provided)
442 ulong dev_get_driver_data(const struct udevice *dev);
445 * dev_get_driver_ops() - get the device's driver's operations
447 * This checks that dev is not NULL, and returns the pointer to device's
448 * driver's operations.
450 * @dev: Device to check
451 * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
453 const void *dev_get_driver_ops(const struct udevice *dev);
456 * device_get_uclass_id() - return the uclass ID of a device
458 * @dev: Device to check
459 * @return uclass ID for the device
461 enum uclass_id device_get_uclass_id(const struct udevice *dev);
464 * dev_get_uclass_name() - return the uclass name of a device
466 * This checks that dev is not NULL.
468 * @dev: Device to check
469 * @return pointer to the uclass name for the device
471 const char *dev_get_uclass_name(const struct udevice *dev);
474 * device_get_child() - Get the child of a device by index
476 * Returns the numbered child, 0 being the first. This does not use
477 * sequence numbers, only the natural order.
479 * @dev: Parent device to check
480 * @index: Child index
481 * @devp: Returns pointer to device
482 * @return 0 if OK, -ENODEV if no such device, other error if the device fails
485 int device_get_child(const struct udevice *parent, int index,
486 struct udevice **devp);
489 * device_get_child_count() - Get the available child count of a device
491 * Returns the number of children to a device.
493 * @parent: Parent device to check
495 int device_get_child_count(const struct udevice *parent);
498 * device_find_child_by_seq() - Find a child device based on a sequence
500 * This searches for a device with the given seq.
502 * @parent: Parent device
503 * @seq: Sequence number to find (0=first)
504 * @devp: Returns pointer to device (there is only one per for each seq).
505 * Set to NULL if none is found
506 * @return 0 if OK, -ENODEV if not found
508 int device_find_child_by_seq(const struct udevice *parent, int seq,
509 struct udevice **devp);
512 * device_get_child_by_seq() - Get a child device based on a sequence
514 * If an active device has this sequence it will be returned. If there is no
515 * such device then this will check for a device that is requesting this
518 * The device is probed to activate it ready for use.
520 * @parent: Parent device
521 * @seq: Sequence number to find (0=first)
522 * @devp: Returns pointer to device (there is only one per for each seq)
523 * Set to NULL if none is found
524 * @return 0 if OK, -ve on error
526 int device_get_child_by_seq(const struct udevice *parent, int seq,
527 struct udevice **devp);
530 * device_find_child_by_of_offset() - Find a child device based on FDT offset
532 * Locates a child device by its device tree offset.
534 * @parent: Parent device
535 * @of_offset: Device tree offset to find
536 * @devp: Returns pointer to device if found, otherwise this is set to NULL
537 * @return 0 if OK, -ve on error
539 int device_find_child_by_of_offset(const struct udevice *parent, int of_offset,
540 struct udevice **devp);
543 * device_get_child_by_of_offset() - Get a child device based on FDT offset
545 * Locates a child device by its device tree offset.
547 * The device is probed to activate it ready for use.
549 * @parent: Parent device
550 * @of_offset: Device tree offset to find
551 * @devp: Returns pointer to device if found, otherwise this is set to NULL
552 * @return 0 if OK, -ve on error
554 int device_get_child_by_of_offset(const struct udevice *parent, int of_offset,
555 struct udevice **devp);
558 * device_find_global_by_ofnode() - Get a device based on ofnode
560 * Locates a device by its device tree ofnode, searching globally throughout
561 * the all driver model devices.
563 * The device is NOT probed
565 * @node: Device tree ofnode to find
566 * @devp: Returns pointer to device if found, otherwise this is set to NULL
567 * @return 0 if OK, -ve on error
570 int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
573 * device_get_global_by_ofnode() - Get a device based on ofnode
575 * Locates a device by its device tree ofnode, searching globally throughout
576 * the all driver model devices.
578 * The device is probed to activate it ready for use.
580 * @node: Device tree ofnode to find
581 * @devp: Returns pointer to device if found, otherwise this is set to NULL
582 * @return 0 if OK, -ve on error
584 int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
587 * device_get_by_driver_info() - Get a device based on driver_info
589 * Locates a device by its struct driver_info, by using its reference which
590 * is updated during the bind process.
592 * The device is probed to activate it ready for use.
594 * @info: Struct driver_info
595 * @devp: Returns pointer to device if found, otherwise this is set to NULL
596 * @return 0 if OK, -ve on error
598 int device_get_by_driver_info(const struct driver_info *info,
599 struct udevice **devp);
602 * device_get_by_driver_info_idx() - Get a device based on driver_info index
604 * Locates a device by its struct driver_info, by using its index number which
605 * is written into the idx field of struct phandle_1_arg, etc.
607 * The device is probed to activate it ready for use.
609 * @idx: Index number of the driver_info structure (0=first)
610 * @devp: Returns pointer to device if found, otherwise this is set to NULL
611 * @return 0 if OK, -ve on error
613 int device_get_by_driver_info_idx(uint idx, struct udevice **devp);
616 * device_find_first_child() - Find the first child of a device
618 * @parent: Parent device to search
619 * @devp: Returns first child device, or NULL if none
622 int device_find_first_child(const struct udevice *parent,
623 struct udevice **devp);
626 * device_find_next_child() - Find the next child of a device
628 * @devp: Pointer to previous child device on entry. Returns pointer to next
629 * child device, or NULL if none
632 int device_find_next_child(struct udevice **devp);
635 * device_find_first_inactive_child() - Find the first inactive child
637 * This is used to locate an existing child of a device which is of a given
640 * The device is NOT probed
642 * @parent: Parent device to search
643 * @uclass_id: Uclass to look for
644 * @devp: Returns device found, if any
645 * @return 0 if found, else -ENODEV
647 int device_find_first_inactive_child(const struct udevice *parent,
648 enum uclass_id uclass_id,
649 struct udevice **devp);
652 * device_find_first_child_by_uclass() - Find the first child of a device in uc
654 * @parent: Parent device to search
655 * @uclass_id: Uclass to look for
656 * @devp: Returns first child device in that uclass, if any
657 * @return 0 if found, else -ENODEV
659 int device_find_first_child_by_uclass(const struct udevice *parent,
660 enum uclass_id uclass_id,
661 struct udevice **devp);
664 * device_find_child_by_name() - Find a child by device name
666 * @parent: Parent device to search
667 * @name: Name to look for
668 * @devp: Returns device found, if any
669 * @return 0 if found, else -ENODEV
671 int device_find_child_by_name(const struct udevice *parent, const char *name,
672 struct udevice **devp);
675 * device_first_child_ofdata_err() - Find the first child and reads its plat
677 * The of_to_plat() method is called on the child before it is returned,
678 * but the child is not probed.
680 * @parent: Parent to check
681 * @devp: Returns child that was found, if any
682 * @return 0 on success, -ENODEV if no children, other -ve on error
684 int device_first_child_ofdata_err(struct udevice *parent,
685 struct udevice **devp);
688 * device_next_child_ofdata_err() - Find the next child and read its plat
690 * The of_to_plat() method is called on the child before it is returned,
691 * but the child is not probed.
693 * @devp: On entry, points to the previous child; on exit returns the child that
695 * @return 0 on success, -ENODEV if no children, other -ve on error
697 int device_next_child_ofdata_err(struct udevice **devp);
700 * device_first_child_err() - Get the first child of a device
702 * The device returned is probed if necessary, and ready for use
704 * @parent: Parent device to search
705 * @devp: Returns device found, if any
706 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
708 int device_first_child_err(struct udevice *parent, struct udevice **devp);
711 * device_next_child_err() - Get the next child of a parent device
713 * The device returned is probed if necessary, and ready for use
715 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
716 * to the next sibling if no error occurred
717 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
719 int device_next_child_err(struct udevice **devp);
722 * device_has_children() - check if a device has any children
724 * @dev: Device to check
725 * @return true if the device has one or more children
727 bool device_has_children(const struct udevice *dev);
730 * device_has_active_children() - check if a device has any active children
732 * @dev: Device to check
733 * @return true if the device has one or more children and at least one of
734 * them is active (probed).
736 bool device_has_active_children(const struct udevice *dev);
739 * device_is_last_sibling() - check if a device is the last sibling
741 * This function can be useful for display purposes, when special action needs
742 * to be taken when displaying the last sibling. This can happen when a tree
743 * view of devices is being displayed.
745 * @dev: Device to check
746 * @return true if there are no more siblings after this one - i.e. is it
749 bool device_is_last_sibling(const struct udevice *dev);
752 * device_set_name() - set the name of a device
754 * This must be called in the device's bind() method and no later. Normally
755 * this is unnecessary but for probed devices which don't get a useful name
756 * this function can be helpful.
758 * The name is allocated and will be freed automatically when the device is
761 * @dev: Device to update
762 * @name: New name (this string is allocated new memory and attached to
764 * @return 0 if OK, -ENOMEM if there is not enough memory to allocate the
767 int device_set_name(struct udevice *dev, const char *name);
770 * device_set_name_alloced() - note that a device name is allocated
772 * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
773 * unbound the name will be freed. This avoids memory leaks.
775 * @dev: Device to update
777 void device_set_name_alloced(struct udevice *dev);
780 * device_is_compatible() - check if the device is compatible with the compat
782 * This allows to check whether the device is comaptible with the compat.
784 * @dev: udevice pointer for which compatible needs to be verified.
785 * @compat: Compatible string which needs to verified in the given
787 * @return true if OK, false if the compatible is not found
789 bool device_is_compatible(const struct udevice *dev, const char *compat);
792 * of_machine_is_compatible() - check if the machine is compatible with
795 * This allows to check whether the machine is comaptible with the compat.
797 * @compat: Compatible string which needs to verified
798 * @return true if OK, false if the compatible is not found
800 bool of_machine_is_compatible(const char *compat);
803 * dev_disable_by_path() - Disable a device given its device tree path
805 * @path: The device tree path identifying the device to be disabled
806 * @return 0 on success, -ve on error
808 int dev_disable_by_path(const char *path);
811 * dev_enable_by_path() - Enable a device given its device tree path
813 * @path: The device tree path identifying the device to be enabled
814 * @return 0 on success, -ve on error
816 int dev_enable_by_path(const char *path);
819 * device_is_on_pci_bus - Test if a device is on a PCI bus
821 * @dev: device to test
822 * @return: true if it is on a PCI bus, false otherwise
824 static inline bool device_is_on_pci_bus(const struct udevice *dev)
826 return dev->parent && device_get_uclass_id(dev->parent) == UCLASS_PCI;
830 * device_foreach_child_safe() - iterate through child devices safely
832 * This allows the @pos child to be removed in the loop if required.
834 * @pos: struct udevice * for the current device
835 * @next: struct udevice * for the next device
836 * @parent: parent device to scan
838 #define device_foreach_child_safe(pos, next, parent) \
839 list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
842 * device_foreach_child() - iterate through child devices
844 * @pos: struct udevice * for the current device
845 * @parent: parent device to scan
847 #define device_foreach_child(pos, parent) \
848 list_for_each_entry(pos, &parent->child_head, sibling_node)
851 * device_foreach_child_of_to_plat() - iterate through children
853 * This stops when it gets an error, with @pos set to the device that failed to
856 * This creates a for() loop which works through the available children of
857 * a device in order from start to end. Device ofdata is read by calling
858 * device_of_to_plat() on each one. The devices are not probed.
860 * @pos: struct udevice * for the current device
861 * @parent: parent device to scan
863 #define device_foreach_child_of_to_plat(pos, parent) \
864 for (int _ret = device_first_child_ofdata_err(parent, &dev); !_ret; \
865 _ret = device_next_child_ofdata_err(&dev))
868 * device_foreach_child_probe() - iterate through children, probing them
870 * This creates a for() loop which works through the available children of
871 * a device in order from start to end. Devices are probed if necessary,
874 * This stops when it gets an error, with @pos set to the device that failed to
877 * @pos: struct udevice * for the current device
878 * @parent: parent device to scan
880 #define device_foreach_child_probe(pos, parent) \
881 for (int _ret = device_first_child_err(parent, &dev); !_ret; \
882 _ret = device_next_child_err(&dev))
885 * dm_scan_fdt_dev() - Bind child device in the device tree
887 * This handles device which have sub-nodes in the device tree. It scans all
888 * sub-nodes and binds drivers for each node where a driver can be found.
890 * If this is called prior to relocation, only pre-relocation devices will be
891 * bound (those marked with u-boot,dm-pre-reloc in the device tree, or where
892 * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
895 * @dev: Device to scan
896 * @return 0 if OK, -ve on error
898 int dm_scan_fdt_dev(struct udevice *dev);