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>
15 #include <dm/uclass-id.h>
17 #include <linker_lists.h>
18 #include <linux/kernel.h>
19 #include <linux/list.h>
20 #include <linux/printk.h>
24 /* Driver is active (probed). Cleared when it is removed */
25 #define DM_FLAG_ACTIVATED (1 << 0)
27 /* DM is responsible for allocating and freeing plat */
28 #define DM_FLAG_ALLOC_PDATA (1 << 1)
30 /* DM should init this device prior to relocation */
31 #define DM_FLAG_PRE_RELOC (1 << 2)
33 /* DM is responsible for allocating and freeing parent_plat */
34 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
36 /* DM is responsible for allocating and freeing uclass_plat */
37 #define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4)
39 /* Allocate driver private data on a DMA boundary */
40 #define DM_FLAG_ALLOC_PRIV_DMA (1 << 5)
43 #define DM_FLAG_BOUND (1 << 6)
45 /* Device name is allocated and should be freed on unbind() */
46 #define DM_FLAG_NAME_ALLOCED (1 << 7)
48 /* Device has platform data provided by of-platdata */
49 #define DM_FLAG_OF_PLATDATA (1 << 8)
52 * Call driver remove function to stop currently active DMA transfers or
53 * give DMA buffers back to the HW / controller. This may be needed for
54 * some drivers to do some final stage cleanup before the OS is called
57 #define DM_FLAG_ACTIVE_DMA (1 << 9)
60 * Call driver remove function to do some final configuration, before
61 * U-Boot exits and the OS is started
63 #define DM_FLAG_OS_PREPARE (1 << 10)
65 /* DM does not enable/disable the power domains corresponding to this device */
66 #define DM_FLAG_DEFAULT_PD_CTRL_OFF (1 << 11)
68 /* Driver plat has been read. Cleared when the device is removed */
69 #define DM_FLAG_PLATDATA_VALID (1 << 12)
72 * Device is removed without switching off its power domain. This might
73 * be required, i. e. for serial console (debug) output when booting OS.
75 #define DM_FLAG_LEAVE_PD_ON (1 << 13)
78 * Device is vital to the operation of other devices. It is possible to remove
79 * removed this device after all regular devices are removed. This is useful
80 * e.g. for clock, which need to be active during the device-removal phase.
82 #define DM_FLAG_VITAL (1 << 14)
84 /* Device must be probed after it was bound */
85 #define DM_FLAG_PROBE_AFTER_BIND (1 << 15)
88 * One or multiple of these flags are passed to device_remove() so that
89 * a selective device removal as specified by the remove-stage and the
90 * driver flags can be done.
92 * DO NOT use these flags in your driver's @flags value...
93 * use the above DM_FLAG_... values instead
96 /* Normal remove, remove all devices */
97 DM_REMOVE_NORMAL = 1 << 0,
99 /* Remove devices with active DMA */
100 DM_REMOVE_ACTIVE_DMA = DM_FLAG_ACTIVE_DMA,
102 /* Remove devices which need some final OS preparation steps */
103 DM_REMOVE_OS_PREPARE = DM_FLAG_OS_PREPARE,
105 /* Remove only devices that are not marked vital */
106 DM_REMOVE_NON_VITAL = DM_FLAG_VITAL,
108 /* Remove devices with any active flag */
109 DM_REMOVE_ACTIVE_ALL = DM_REMOVE_ACTIVE_DMA | DM_REMOVE_OS_PREPARE,
111 /* Don't power down any attached power domains */
112 DM_REMOVE_NO_PD = 1 << 1,
116 * struct udevice - An instance of a driver
118 * This holds information about a device, which is a driver bound to a
119 * particular port or peripheral (essentially a driver instance).
121 * A device will come into existence through a 'bind' call, either due to
122 * a U_BOOT_DRVINFO() macro (in which case plat is non-NULL) or a node
123 * in the device tree (in which case of_offset is >= 0). In the latter case
124 * we translate the device tree information into plat in a function
125 * implemented by the driver of_to_plat method (called just before the
126 * probe method if the device has a device tree node.
128 * All three of plat, priv and uclass_priv can be allocated by the
129 * driver, or you can use the auto members of struct driver and
130 * struct uclass_driver to have driver model do this automatically.
132 * @driver: The driver used by this device
133 * @name: Name of device, typically the FDT node name
134 * @plat_: Configuration data for this device (do not access outside driver
136 * @parent_plat_: The parent bus's configuration data for this device (do not
137 * access outside driver model)
138 * @uclass_plat_: The uclass's configuration data for this device (do not access
139 * outside driver model)
140 * @driver_data: Driver data word for the entry that matched this device with
142 * @parent: Parent of this device, or NULL for the top level device
143 * @priv_: Private data for this device (do not access outside driver model)
144 * @uclass: Pointer to uclass for this device
145 * @uclass_priv_: The uclass's private data for this device (do not access
146 * outside driver model)
147 * @parent_priv_: The parent's private data for this device (do not access
148 * outside driver model)
149 * @uclass_node: Used by uclass to link its devices
150 * @child_head: List of children of this device
151 * @sibling_node: Next device in list of all devices
152 * @flags_: Flags for this device `DM_FLAG_...` (do not access outside driver
154 * @seq_: Allocated sequence number for this device (-1 = none). This is set up
155 * when the device is bound and is unique within the device's uclass. If the
156 * device has an alias in the devicetree then that is used to set the sequence
157 * number. Otherwise, the next available number is used. Sequence numbers are
158 * used by certain commands that need device to be numbered (e.g. 'mmc dev').
159 * (do not access outside driver model)
160 * @node_: Reference to device tree node for this device (do not access outside
162 * @devres_head: List of memory allocations associated with this device.
163 * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
164 * add to this list. Memory so-allocated will be freed
165 * automatically when the device is removed / unbound
166 * @dma_offset: Offset between the physical address space (CPU's) and the
167 * device's bus address space
168 * @iommu: IOMMU device associated with this device
171 const struct driver *driver;
177 struct udevice *parent;
179 struct uclass *uclass;
182 struct list_head uclass_node;
183 struct list_head child_head;
184 struct list_head sibling_node;
185 #if !CONFIG_IS_ENABLED(OF_PLATDATA_RT)
189 #if CONFIG_IS_ENABLED(OF_REAL)
192 #if CONFIG_IS_ENABLED(DEVRES)
193 struct list_head devres_head;
195 #if CONFIG_IS_ENABLED(DM_DMA)
198 #if CONFIG_IS_ENABLED(IOMMU)
199 struct udevice *iommu;
203 static inline int dm_udevice_size(void)
205 if (CONFIG_IS_ENABLED(OF_PLATDATA_RT))
206 return ALIGN(sizeof(struct udevice), CONFIG_LINKER_LIST_ALIGN);
208 return sizeof(struct udevice);
212 * struct udevice_rt - runtime information set up by U-Boot
214 * This is only used with OF_PLATDATA_RT
216 * There is one of these for every udevice in the linker list, indexed by
217 * the udevice_info idx value.
219 * @flags_: Flags for this device `DM_FLAG_...` (do not access outside driver
226 /* Maximum sequence number supported and associated string length */
227 #define DM_MAX_SEQ 999
228 #define DM_MAX_SEQ_STR 3
230 /* Returns the operations for a device */
231 #define device_get_ops(dev) ((dev)->driver->ops)
233 #if CONFIG_IS_ENABLED(OF_PLATDATA_RT)
234 u32 dev_get_flags(const struct udevice *dev);
235 void dev_or_flags(const struct udevice *dev, u32 or);
236 void dev_bic_flags(const struct udevice *dev, u32 bic);
238 static inline u32 dev_get_flags(const struct udevice *dev)
243 static inline void dev_or_flags(struct udevice *dev, u32 or)
248 static inline void dev_bic_flags(struct udevice *dev, u32 bic)
252 #endif /* OF_PLATDATA_RT */
255 * dev_ofnode() - get the DT node reference associated with a udevice
257 * @dev: device to check
258 * Return: reference of the device's DT node
260 static inline __attribute_const__ ofnode dev_ofnode(const struct udevice *dev)
262 #if CONFIG_IS_ENABLED(OF_REAL)
265 return ofnode_null();
269 /* Returns non-zero if the device is active (probed and not removed) */
270 #define device_active(dev) (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
272 #if CONFIG_IS_ENABLED(DM_DMA)
273 #define dev_set_dma_offset(_dev, _offset) _dev->dma_offset = _offset
274 #define dev_get_dma_offset(_dev) _dev->dma_offset
276 #define dev_set_dma_offset(_dev, _offset)
277 #define dev_get_dma_offset(_dev) 0
280 static inline __attribute_const__ int dev_of_offset(const struct udevice *dev)
282 #if CONFIG_IS_ENABLED(OF_REAL)
283 return ofnode_to_offset(dev_ofnode(dev));
289 static inline __attribute_const__ bool dev_has_ofnode(const struct udevice *dev)
291 #if CONFIG_IS_ENABLED(OF_REAL)
292 return ofnode_valid(dev_ofnode(dev));
298 static inline void dev_set_ofnode(struct udevice *dev, ofnode node)
300 #if CONFIG_IS_ENABLED(OF_REAL)
305 static inline int dev_seq(const struct udevice *dev)
311 * struct udevice_id - Lists the compatible strings supported by a driver
312 * @compatible: Compatible string
313 * @data: Data for this compatible string
316 const char *compatible;
320 #if CONFIG_IS_ENABLED(OF_REAL)
321 #define of_match_ptr(_ptr) (_ptr)
323 #define of_match_ptr(_ptr) NULL
324 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
327 * struct driver - A driver for a feature or peripheral
329 * This holds methods for setting up a new device, and also removing it.
330 * The device needs information to set itself up - this is provided either
331 * by plat or a device tree node (which we find by looking up
332 * matching compatible strings with of_match).
334 * Drivers all belong to a uclass, representing a class of devices of the
335 * same type. Common elements of the drivers can be implemented in the uclass,
336 * or the uclass can provide a consistent interface to the drivers within
340 * @id: Identifies the uclass we belong to
341 * @of_match: List of compatible strings to match, and any identifying data
343 * @bind: Called to bind a device to its driver
344 * @probe: Called to probe a device, i.e. activate it
345 * @remove: Called to remove a device, i.e. de-activate it
346 * @unbind: Called to unbind a device from its driver
347 * @of_to_plat: Called before probe to decode device tree data
348 * @child_post_bind: Called after a new child has been bound
349 * @child_pre_probe: Called before a child device is probed. The device has
350 * memory allocated but it has not yet been probed.
351 * @child_post_remove: Called after a child device is removed. The device
352 * has memory allocated but its device_remove() method has been called.
353 * @priv_auto: If non-zero this is the size of the private data
354 * to be allocated in the device's ->priv pointer. If zero, then the driver
355 * is responsible for allocating any data required.
356 * @plat_auto: If non-zero this is the size of the
357 * platform data to be allocated in the device's ->plat pointer.
358 * This is typically only useful for device-tree-aware drivers (those with
359 * an of_match), since drivers which use plat will have the data
360 * provided in the U_BOOT_DRVINFO() instantiation.
361 * @per_child_auto: Each device can hold private data owned by
362 * its parent. If required this will be automatically allocated if this
364 * @per_child_plat_auto: A bus likes to store information about
365 * its children. If non-zero this is the size of this data, to be allocated
366 * in the child's parent_plat pointer.
367 * @ops: Driver-specific operations. This is typically a list of function
368 * pointers defined by the driver, to implement driver functions required by
370 * @flags: driver flags - see `DM_FLAG_...`
371 * @acpi_ops: Advanced Configuration and Power Interface (ACPI) operations,
372 * allowing the device to add things to the ACPI tables passed to Linux
377 const struct udevice_id *of_match;
378 int (*bind)(struct udevice *dev);
379 int (*probe)(struct udevice *dev);
380 int (*remove)(struct udevice *dev);
381 int (*unbind)(struct udevice *dev);
382 int (*of_to_plat)(struct udevice *dev);
383 int (*child_post_bind)(struct udevice *dev);
384 int (*child_pre_probe)(struct udevice *dev);
385 int (*child_post_remove)(struct udevice *dev);
389 int per_child_plat_auto;
390 const void *ops; /* driver-specific operations */
392 #if CONFIG_IS_ENABLED(ACPIGEN)
393 struct acpi_ops *acpi_ops;
398 * U_BOOT_DRIVER() - Declare a new U-Boot driver
399 * @__name: name of the driver
401 #define U_BOOT_DRIVER(__name) \
402 ll_entry_declare(struct driver, __name, driver)
405 * DM_DRIVER_GET() - Get a pointer to a given driver
407 * This is useful in code for referencing a driver at build time.
408 * Before this is used, an extern U_BOOT_DRIVER() must have been
411 * @__name: Name of the driver. This must be a valid C identifier,
412 * used by the linker_list
413 * Return: struct driver * for the driver
415 #define DM_DRIVER_GET(__name) \
416 ll_entry_get(struct driver, __name, driver)
419 * DM_DRIVER_REF() - Get a reference to a driver
421 * This is useful in data structures and code for referencing a driver at
422 * build time. Before this is used, an extern U_BOOT_DRIVER() must have been
424 * This is like DM_DRIVER_GET, but without the extra code, so it is suitable
425 * for putting into data structures.
429 * extern U_BOOT_DRIVER(sandbox_fixed_clock);
430 * struct driver *drvs[] = {
431 * DM_DRIVER_REF(sandbox_fixed_clock),
434 * @_name: Name of the driver. This must be a valid C identifier,
435 * used by the linker_list
436 * Return: struct driver * for the driver
438 #define DM_DRIVER_REF(_name) \
439 ll_entry_ref(struct driver, _name, driver)
442 * DM_DRIVER_ALIAS() - Declare a macro to state an alias for a driver name
444 * This macro will produce no code but its information will be parsed by tools
447 * @__name: name of driver
448 * @__alias: alias for the driver name
450 #define DM_DRIVER_ALIAS(__name, __alias)
453 * DM_PHASE() - Declare a macro to indicate which phase of U-Boot this driver is for.
455 * This macro produces no code but its information will be parsed by dtoc. The
456 * macro can be only be used once in a driver. Put it within the U_BOOT_DRIVER()
457 * declaration, e.g.::
459 * U_BOOT_DRIVER(cpu) = {
465 * @_phase: Associated phase of U-Boot ("spl", "tpl")
467 #define DM_PHASE(_phase)
470 * DM_HEADER() - Declare a macro to declare a header needed for a driver.
472 * Often the correct header can be found automatically, but only for struct
473 * declarations. For enums and #defines used in the driver declaration and
474 * declared in a different header from the structs, this macro must be used.
476 * This macro produces no code but its information will be parsed by dtoc. The
477 * macro can be used multiple times with different headers, for the same driver.
478 * Put it within the U_BOOT_DRIVER() declaration, e.g.::
480 * U_BOOT_DRIVER(cpu) = {
483 * DM_HEADER(<asm/cpu.h>)
486 * @_hdr: header needed for a driver
488 #define DM_HEADER(_hdr)
491 * dev_get_plat() - Get the platform data for a device
493 * This checks that dev is not NULL, but no other checks for now
495 * @dev: Device to check
496 * Return: platform data, or NULL if none
498 void *dev_get_plat(const struct udevice *dev);
501 * dev_get_parent_plat() - Get the parent platform data for a device
503 * This checks that dev is not NULL, but no other checks for now
505 * @dev: Device to check
506 * Return: parent's platform data, or NULL if none
508 void *dev_get_parent_plat(const struct udevice *dev);
511 * dev_get_uclass_plat() - Get the uclass platform data for a device
513 * This checks that dev is not NULL, but no other checks for now
515 * @dev: Device to check
516 * Return: uclass's platform data, or NULL if none
518 void *dev_get_uclass_plat(const struct udevice *dev);
521 * dev_get_priv() - Get the private data for a device
523 * This checks that dev is not NULL, but no other checks for now
525 * @dev: Device to check
526 * Return: private data, or NULL if none
528 void *dev_get_priv(const struct udevice *dev);
531 * dev_get_parent_priv() - Get the parent private data for a device
533 * The parent private data is data stored in the device but owned by the
534 * parent. For example, a USB device may have parent data which contains
535 * information about how to talk to the device over USB.
537 * This checks that dev is not NULL, but no other checks for now
539 * @dev: Device to check
540 * Return: parent data, or NULL if none
542 void *dev_get_parent_priv(const struct udevice *dev);
545 * dev_get_uclass_priv() - Get the private uclass data for a device
547 * This checks that dev is not NULL, but no other checks for now
549 * @dev: Device to check
550 * Return: private uclass data for this device, or NULL if none
552 void *dev_get_uclass_priv(const struct udevice *dev);
555 * dev_get_attach_ptr() - Get the value of an attached pointed tag
557 * The tag is assumed to hold a pointer, if it exists
559 * @dev: Device to look at
560 * @tag: Tag to access
561 * @return value of tag, or NULL if there is no tag of this type
563 void *dev_get_attach_ptr(const struct udevice *dev, enum dm_tag_t tag);
566 * dev_get_attach_size() - Get the size of an attached tag
568 * Core tags have an automatic-allocation mechanism where the allocated size is
569 * defined by the device, parent or uclass. This returns the size associated
570 * with a particular tag
572 * @dev: Device to look at
573 * @tag: Tag to access
574 * @return size of auto-allocated data, 0 if none
576 int dev_get_attach_size(const struct udevice *dev, enum dm_tag_t tag);
579 * dev_get_parent() - Get the parent of a device
581 * @child: Child to check
582 * Return: parent of child, or NULL if this is the root device
584 struct udevice *dev_get_parent(const struct udevice *child);
587 * dev_get_driver_data() - get the driver data used to bind a device
589 * When a device is bound using a device tree node, it matches a
590 * particular compatible string in struct udevice_id. This function
591 * returns the associated data value for that compatible string. This is
592 * the 'data' field in struct udevice_id.
594 * As an example, consider this structure::
596 * static const struct udevice_id tegra_i2c_ids[] = {
597 * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
598 * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
599 * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
603 * When driver model finds a driver for this it will store the 'data' value
604 * corresponding to the compatible string it matches. This function returns
605 * that value. This allows the driver to handle several variants of a device.
607 * For USB devices, this is the driver_info field in struct usb_device_id.
609 * @dev: Device to check
610 * Return: driver data (0 if none is provided)
612 ulong dev_get_driver_data(const struct udevice *dev);
615 * dev_get_driver_ops() - get the device's driver's operations
617 * This checks that dev is not NULL, and returns the pointer to device's
618 * driver's operations.
620 * @dev: Device to check
621 * Return: void pointer to driver's operations or NULL for NULL-dev or NULL-ops
623 const void *dev_get_driver_ops(const struct udevice *dev);
626 * device_get_uclass_id() - return the uclass ID of a device
628 * @dev: Device to check
629 * Return: uclass ID for the device
631 enum uclass_id device_get_uclass_id(const struct udevice *dev);
634 * dev_get_uclass_name() - return the uclass name of a device
636 * This checks that dev is not NULL.
638 * @dev: Device to check
639 * Return: pointer to the uclass name for the device
641 const char *dev_get_uclass_name(const struct udevice *dev);
644 * device_get_child() - Get the child of a device by index
646 * Returns the numbered child, 0 being the first. This does not use
647 * sequence numbers, only the natural order.
649 * @parent: Parent device to check
650 * @index: Child index
651 * @devp: Returns pointer to device
653 * 0 if OK, -ENODEV if no such device, other error if the device fails to probe
655 int device_get_child(const struct udevice *parent, int index,
656 struct udevice **devp);
659 * device_get_child_count() - Get the child count of a device
661 * Returns the number of children to a device.
663 * @parent: Parent device to check
665 int device_get_child_count(const struct udevice *parent);
668 * device_get_decendent_count() - Get the total number of decendents of a device
670 * Returns the total number of decendents, including all children
672 * @parent: Parent device to check
674 int device_get_decendent_count(const struct udevice *parent);
677 * device_find_child_by_seq() - Find a child device based on a sequence
679 * This searches for a device with the given seq.
681 * @parent: Parent device
682 * @seq: Sequence number to find (0=first)
683 * @devp: Returns pointer to device (there is only one per for each seq).
684 * Set to NULL if none is found
685 * Return: 0 if OK, -ENODEV if not found
687 int device_find_child_by_seq(const struct udevice *parent, int seq,
688 struct udevice **devp);
691 * device_get_child_by_seq() - Get a child device based on a sequence
693 * If an active device has this sequence it will be returned. If there is no
694 * such device then this will check for a device that is requesting this
697 * The device is probed to activate it ready for use.
699 * @parent: Parent device
700 * @seq: Sequence number to find (0=first)
701 * @devp: Returns pointer to device (there is only one per for each seq)
702 * Set to NULL if none is found
703 * Return: 0 if OK, -ve on error
705 int device_get_child_by_seq(const struct udevice *parent, int seq,
706 struct udevice **devp);
709 * device_find_child_by_of_offset() - Find a child device based on FDT offset
711 * Locates a child device by its device tree offset.
713 * @parent: Parent device
714 * @of_offset: Device tree offset to find
715 * @devp: Returns pointer to device if found, otherwise this is set to NULL
716 * Return: 0 if OK, -ve on error
718 int device_find_child_by_of_offset(const struct udevice *parent, int of_offset,
719 struct udevice **devp);
722 * device_get_child_by_of_offset() - Get a child device based on FDT offset
724 * Locates a child device by its device tree offset.
726 * The device is probed to activate it ready for use.
728 * @parent: Parent device
729 * @of_offset: Device tree offset to find
730 * @devp: Returns pointer to device if found, otherwise this is set to NULL
731 * Return: 0 if OK, -ve on error
733 int device_get_child_by_of_offset(const struct udevice *parent, int of_offset,
734 struct udevice **devp);
737 * device_find_global_by_ofnode() - Get a device based on ofnode
739 * Locates a device by its device tree ofnode, searching globally throughout
740 * the all driver model devices.
742 * The device is NOT probed
744 * @node: Device tree ofnode to find
745 * @devp: Returns pointer to device if found, otherwise this is set to NULL
746 * Return: 0 if OK, -ve on error
749 int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
752 * device_get_global_by_ofnode() - Get a device based on ofnode
754 * Locates a device by its device tree ofnode, searching globally throughout
755 * the all driver model devices.
757 * The device is probed to activate it ready for use.
759 * @node: Device tree ofnode to find
760 * @devp: Returns pointer to device if found, otherwise this is set to NULL
761 * Return: 0 if OK, -ve on error
763 int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
766 * device_get_by_ofplat_idx() - Get a device based on of-platdata index
768 * Locates a device by either its struct driver_info index, or its
769 * struct udevice index. The latter is used with OF_PLATDATA_INST, since we have
770 * a list of build-time instantiated struct udevice records, The former is used
771 * with !OF_PLATDATA_INST since in that case we have a list of
772 * struct driver_info records.
774 * The index number is written into the idx field of struct phandle_1_arg, etc.
775 * It is the position of this driver_info/udevice in its linker list.
777 * The device is probed to activate it ready for use.
779 * @idx: Index number of the driver_info/udevice structure (0=first)
780 * @devp: Returns pointer to device if found, otherwise this is set to NULL
781 * Return: 0 if OK, -ve on error
783 int device_get_by_ofplat_idx(uint idx, struct udevice **devp);
786 * device_find_first_child() - Find the first child of a device
788 * @parent: Parent device to search
789 * @devp: Returns first child device, or NULL if none
792 int device_find_first_child(const struct udevice *parent,
793 struct udevice **devp);
796 * device_find_next_child() - Find the next child of a device
798 * @devp: Pointer to previous child device on entry. Returns pointer to next
799 * child device, or NULL if none
802 int device_find_next_child(struct udevice **devp);
805 * device_find_first_inactive_child() - Find the first inactive child
807 * This is used to locate an existing child of a device which is of a given
810 * The device is NOT probed
812 * @parent: Parent device to search
813 * @uclass_id: Uclass to look for
814 * @devp: Returns device found, if any, else NULL
815 * Return: 0 if found, else -ENODEV
817 int device_find_first_inactive_child(const struct udevice *parent,
818 enum uclass_id uclass_id,
819 struct udevice **devp);
822 * device_find_first_child_by_uclass() - Find the first child of a device in uc
824 * @parent: Parent device to search
825 * @uclass_id: Uclass to look for
826 * @devp: Returns first child device in that uclass, if any, else NULL
827 * Return: 0 if found, else -ENODEV
829 int device_find_first_child_by_uclass(const struct udevice *parent,
830 enum uclass_id uclass_id,
831 struct udevice **devp);
834 * device_find_child_by_namelen() - Find a child by device name
836 * @parent: Parent device to search
837 * @name: Name to look for
838 * @len: Length of the name
839 * @devp: Returns device found, if any
840 * Return: 0 if found, else -ENODEV
842 int device_find_child_by_namelen(const struct udevice *parent, const char *name,
843 int len, struct udevice **devp);
846 * device_find_child_by_name() - Find a child by device name
848 * @parent: Parent device to search
849 * @name: Name to look for
850 * @devp: Returns device found, if any
851 * Return: 0 if found, else -ENODEV
853 int device_find_child_by_name(const struct udevice *parent, const char *name,
854 struct udevice **devp);
857 * device_first_child_ofdata_err() - Find the first child and reads its plat
859 * The of_to_plat() method is called on the child before it is returned,
860 * but the child is not probed.
862 * @parent: Parent to check
863 * @devp: Returns child that was found, if any
864 * Return: 0 on success, -ENODEV if no children, other -ve on error
866 int device_first_child_ofdata_err(struct udevice *parent,
867 struct udevice **devp);
870 * device_next_child_ofdata_err() - Find the next child and read its plat
872 * The of_to_plat() method is called on the child before it is returned,
873 * but the child is not probed.
875 * @devp: On entry, points to the previous child; on exit returns the child that
877 * Return: 0 on success, -ENODEV if no children, other -ve on error
879 int device_next_child_ofdata_err(struct udevice **devp);
882 * device_first_child_err() - Get the first child of a device
884 * The device returned is probed if necessary, and ready for use
886 * @parent: Parent device to search
887 * @devp: Returns device found, if any
888 * Return: 0 if found, -ENODEV if not, -ve error if device failed to probe
890 int device_first_child_err(struct udevice *parent, struct udevice **devp);
893 * device_next_child_err() - Get the next child of a parent device
895 * The device returned is probed if necessary, and ready for use
897 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
898 * to the next sibling if no error occurred
899 * Return: 0 if found, -ENODEV if not, -ve error if device failed to probe
901 int device_next_child_err(struct udevice **devp);
904 * device_has_children() - check if a device has any children
906 * @dev: Device to check
907 * Return: true if the device has one or more children
909 bool device_has_children(const struct udevice *dev);
912 * device_has_active_children() - check if a device has any active children
914 * @dev: Device to check
915 * Return: true if the device has one or more children and at least one of
916 * them is active (probed).
918 bool device_has_active_children(const struct udevice *dev);
921 * device_is_last_sibling() - check if a device is the last sibling
923 * This function can be useful for display purposes, when special action needs
924 * to be taken when displaying the last sibling. This can happen when a tree
925 * view of devices is being displayed.
927 * @dev: Device to check
928 * Return: true if there are no more siblings after this one - i.e. is it
931 bool device_is_last_sibling(const struct udevice *dev);
934 * device_set_name() - set the name of a device
936 * This must be called in the device's bind() method and no later. Normally
937 * this is unnecessary but for probed devices which don't get a useful name
938 * this function can be helpful.
940 * The name is allocated and will be freed automatically when the device is
943 * @dev: Device to update
944 * @name: New name (this string is allocated new memory and attached to
946 * Return: 0 if OK, -ENOMEM if there is not enough memory to allocate the
949 int device_set_name(struct udevice *dev, const char *name);
952 * device_set_name_alloced() - note that a device name is allocated
954 * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
955 * unbound the name will be freed. This avoids memory leaks.
957 * @dev: Device to update
959 void device_set_name_alloced(struct udevice *dev);
962 * device_is_compatible() - check if the device is compatible with the compat
964 * This allows to check whether the device is comaptible with the compat.
966 * @dev: udevice pointer for which compatible needs to be verified.
967 * @compat: Compatible string which needs to verified in the given
969 * Return: true if OK, false if the compatible is not found
971 bool device_is_compatible(const struct udevice *dev, const char *compat);
974 * of_machine_is_compatible() - check if the machine is compatible with
977 * This allows to check whether the machine is comaptible with the compat.
979 * @compat: Compatible string which needs to verified
980 * Return: true if OK, false if the compatible is not found
982 bool of_machine_is_compatible(const char *compat);
985 * dev_disable_by_path() - Disable a device given its device tree path
987 * @path: The device tree path identifying the device to be disabled
988 * Return: 0 on success, -ve on error
990 int dev_disable_by_path(const char *path);
993 * dev_enable_by_path() - Enable a device given its device tree path
995 * @path: The device tree path identifying the device to be enabled
996 * Return: 0 on success, -ve on error
998 int dev_enable_by_path(const char *path);
1001 * device_is_on_pci_bus - Test if a device is on a PCI bus
1003 * @dev: device to test
1004 * Return: true if it is on a PCI bus, false otherwise
1006 static inline bool device_is_on_pci_bus(const struct udevice *dev)
1008 return dev->parent && device_get_uclass_id(dev->parent) == UCLASS_PCI;
1012 * device_foreach_child_safe() - iterate through child devices safely
1014 * This allows the @pos child to be removed in the loop if required.
1016 * @pos: struct udevice * for the current device
1017 * @next: struct udevice * for the next device
1018 * @parent: parent device to scan
1020 #define device_foreach_child_safe(pos, next, parent) \
1021 list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
1024 * device_foreach_child() - iterate through child devices
1026 * @pos: struct udevice * for the current device
1027 * @parent: parent device to scan
1029 #define device_foreach_child(pos, parent) \
1030 list_for_each_entry(pos, &parent->child_head, sibling_node)
1033 * device_foreach_child_of_to_plat() - iterate through children
1035 * This stops when it gets an error, with @pos set to the device that failed to
1038 * This creates a for() loop which works through the available children of
1039 * a device in order from start to end. Device ofdata is read by calling
1040 * device_of_to_plat() on each one. The devices are not probed.
1042 * @pos: struct udevice * for the current device
1043 * @parent: parent device to scan
1045 #define device_foreach_child_of_to_plat(pos, parent) \
1046 for (int _ret = device_first_child_ofdata_err(parent, &pos); !_ret; \
1047 _ret = device_next_child_ofdata_err(&pos))
1050 * device_foreach_child_probe() - iterate through children, probing them
1052 * This creates a for() loop which works through the available children of
1053 * a device in order from start to end. Devices are probed if necessary,
1054 * and ready for use.
1056 * This stops when it gets an error, with @pos set to the device that failed to
1059 * @pos: struct udevice * for the current device
1060 * @parent: parent device to scan
1062 #define device_foreach_child_probe(pos, parent) \
1063 for (int _ret = device_first_child_err(parent, &pos); !_ret; \
1064 _ret = device_next_child_err(&pos))
1067 * dm_scan_fdt_dev() - Bind child device in the device tree
1069 * This handles device which have sub-nodes in the device tree. It scans all
1070 * sub-nodes and binds drivers for each node where a driver can be found.
1072 * If this is called prior to relocation, only pre-relocation devices will be
1073 * bound (those marked with bootph-all in the device tree, or where
1074 * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
1077 * @dev: Device to scan
1078 * Return: 0 if OK, -ve on error
1080 int dm_scan_fdt_dev(struct udevice *dev);