1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * Copyright (c) 2013 Google, Inc
4 *
5 * (C) Copyright 2012
6 * Pavel Herrmann <morpheus.ibis@gmail.com>
7 * Marek Vasut <marex@denx.de>
8 */
9
10 #ifndef _DM_DEVICE_H
11 #define _DM_DEVICE_H
12
13 #include <dm/ofnode.h>
14 #include <dm/tag.h>
15 #include <dm/uclass-id.h>
16 #include <fdtdec.h>
17 #include <linker_lists.h>
18 #include <linux/kernel.h>
19 #include <linux/list.h>
20 #include <linux/printk.h>
21
22 struct driver_info;
23
24 /* Driver is active (probed). Cleared when it is removed */
25 #define DM_FLAG_ACTIVATED (1 << 0)
26
27 /* DM is responsible for allocating and freeing plat */
28 #define DM_FLAG_ALLOC_PDATA (1 << 1)
29
30 /* DM should init this device prior to relocation */
31 #define DM_FLAG_PRE_RELOC (1 << 2)
32
33 /* DM is responsible for allocating and freeing parent_plat */
34 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
35
36 /* DM is responsible for allocating and freeing uclass_plat */
37 #define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4)
38
39 /* Allocate driver private data on a DMA boundary */
40 #define DM_FLAG_ALLOC_PRIV_DMA (1 << 5)
41
42 /* Device is bound */
43 #define DM_FLAG_BOUND (1 << 6)
44
45 /* Device name is allocated and should be freed on unbind() */
46 #define DM_FLAG_NAME_ALLOCED (1 << 7)
47
48 /* Device has platform data provided by of-platdata */
49 #define DM_FLAG_OF_PLATDATA (1 << 8)
50
51 /*
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
55 * (U-Boot exit)
56 */
57 #define DM_FLAG_ACTIVE_DMA (1 << 9)
58
59 /*
60 * Call driver remove function to do some final configuration, before
61 * U-Boot exits and the OS is started
62 */
63 #define DM_FLAG_OS_PREPARE (1 << 10)
64
65 /* DM does not enable/disable the power domains corresponding to this device */
66 #define DM_FLAG_DEFAULT_PD_CTRL_OFF (1 << 11)
67
68 /* Driver plat has been read. Cleared when the device is removed */
69 #define DM_FLAG_PLATDATA_VALID (1 << 12)
70
71 /*
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.
74 */
75 #define DM_FLAG_LEAVE_PD_ON (1 << 13)
76
77 /*
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.
81 */
82 #define DM_FLAG_VITAL (1 << 14)
83
84 /* Device must be probed after it was bound. This flag is per-device and does
85 * nothing if set on a U_BOOT_DRIVER() definition. Apply it with
86 * dev_or_flags(dev, DM_FLAG_PROBE_AFTER_BIND) in the devices bind function.
87 */
88 #define DM_FLAG_PROBE_AFTER_BIND (1 << 15)
89
90 /*
91 * One or multiple of these flags are passed to device_remove() so that
92 * a selective device removal as specified by the remove-stage and the
93 * driver flags can be done.
94 *
95 * DO NOT use these flags in your driver's @flags value...
96 * use the above DM_FLAG_... values instead
97 */
98 enum {
99 /* Normal remove, remove all devices */
100 DM_REMOVE_NORMAL = 1 << 0,
101
102 /* Remove devices with active DMA */
103 DM_REMOVE_ACTIVE_DMA = DM_FLAG_ACTIVE_DMA,
104
105 /* Remove devices which need some final OS preparation steps */
106 DM_REMOVE_OS_PREPARE = DM_FLAG_OS_PREPARE,
107
108 /* Remove only devices that are not marked vital */
109 DM_REMOVE_NON_VITAL = DM_FLAG_VITAL,
110
111 /* Remove devices with any active flag */
112 DM_REMOVE_ACTIVE_ALL = DM_REMOVE_ACTIVE_DMA | DM_REMOVE_OS_PREPARE,
113
114 /* Don't power down any attached power domains */
115 DM_REMOVE_NO_PD = 1 << 1,
116 };
117
118 /**
119 * struct udevice - An instance of a driver
120 *
121 * This holds information about a device, which is a driver bound to a
122 * particular port or peripheral (essentially a driver instance).
123 *
124 * A device will come into existence through a 'bind' call, either due to
125 * a U_BOOT_DRVINFO() macro (in which case plat is non-NULL) or a node
126 * in the device tree (in which case of_offset is >= 0). In the latter case
127 * we translate the device tree information into plat in a function
128 * implemented by the driver of_to_plat method (called just before the
129 * probe method if the device has a device tree node.
130 *
131 * All three of plat, priv and uclass_priv can be allocated by the
132 * driver, or you can use the auto members of struct driver and
133 * struct uclass_driver to have driver model do this automatically.
134 *
135 * @driver: The driver used by this device
136 * @name: Name of device, typically the FDT node name
137 * @plat_: Configuration data for this device (do not access outside driver
138 * model)
139 * @parent_plat_: The parent bus's configuration data for this device (do not
140 * access outside driver model)
141 * @uclass_plat_: The uclass's configuration data for this device (do not access
142 * outside driver model)
143 * @driver_data: Driver data word for the entry that matched this device with
144 * its driver
145 * @parent: Parent of this device, or NULL for the top level device
146 * @priv_: Private data for this device (do not access outside driver model)
147 * @uclass: Pointer to uclass for this device
148 * @uclass_priv_: The uclass's private data for this device (do not access
149 * outside driver model)
150 * @parent_priv_: The parent's private data for this device (do not access
151 * outside driver model)
152 * @uclass_node: Used by uclass to link its devices
153 * @child_head: List of children of this device
154 * @sibling_node: Next device in list of all devices
155 * @flags_: Flags for this device `DM_FLAG_...` (do not access outside driver
156 * model)
157 * @seq_: Allocated sequence number for this device (-1 = none). This is set up
158 * when the device is bound and is unique within the device's uclass. If the
159 * device has an alias in the devicetree then that is used to set the sequence
160 * number. Otherwise, the next available number is used. Sequence numbers are
161 * used by certain commands that need device to be numbered (e.g. 'mmc dev').
162 * (do not access outside driver model)
163 * @node_: Reference to device tree node for this device (do not access outside
164 * driver model)
165 * @devres_head: List of memory allocations associated with this device.
166 * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
167 * add to this list. Memory so-allocated will be freed
168 * automatically when the device is removed / unbound
169 * @dma_offset: Offset between the physical address space (CPU's) and the
170 * device's bus address space
171 * @iommu: IOMMU device associated with this device
172 */
173 struct udevice {
174 const struct driver *driver;
175 const char *name;
176 void *plat_;
177 void *parent_plat_;
178 void *uclass_plat_;
179 ulong driver_data;
180 struct udevice *parent;
181 void *priv_;
182 struct uclass *uclass;
183 void *uclass_priv_;
184 void *parent_priv_;
185 struct list_head uclass_node;
186 struct list_head child_head;
187 struct list_head sibling_node;
188 #if !CONFIG_IS_ENABLED(OF_PLATDATA_RT)
189 u32 flags_;
190 #endif
191 int seq_;
192 #if CONFIG_IS_ENABLED(OF_REAL)
193 ofnode node_;
194 #endif
195 #if CONFIG_IS_ENABLED(DEVRES)
196 struct list_head devres_head;
197 #endif
198 #if CONFIG_IS_ENABLED(DM_DMA)
199 ulong dma_offset;
200 #endif
201 #if CONFIG_IS_ENABLED(IOMMU)
202 struct udevice *iommu;
203 #endif
204 };
205
dm_udevice_size(void)206 static inline int dm_udevice_size(void)
207 {
208 if (CONFIG_IS_ENABLED(OF_PLATDATA_RT))
209 return ALIGN(sizeof(struct udevice), CONFIG_LINKER_LIST_ALIGN);
210
211 return sizeof(struct udevice);
212 }
213
214 /**
215 * struct udevice_rt - runtime information set up by U-Boot
216 *
217 * This is only used with OF_PLATDATA_RT
218 *
219 * There is one of these for every udevice in the linker list, indexed by
220 * the udevice_info idx value.
221 *
222 * @flags_: Flags for this device `DM_FLAG_...` (do not access outside driver
223 * model)
224 */
225 struct udevice_rt {
226 u32 flags_;
227 };
228
229 /* Maximum sequence number supported and associated string length */
230 #define DM_MAX_SEQ 999
231 #define DM_MAX_SEQ_STR 3
232
233 /* Returns the operations for a device */
234 #define device_get_ops(dev) ((dev)->driver->ops)
235
236 #if CONFIG_IS_ENABLED(OF_PLATDATA_RT)
237 u32 dev_get_flags(const struct udevice *dev);
238 void dev_or_flags(const struct udevice *dev, u32 or);
239 void dev_bic_flags(const struct udevice *dev, u32 bic);
240 #else
dev_get_flags(const struct udevice * dev)241 static inline u32 dev_get_flags(const struct udevice *dev)
242 {
243 return dev->flags_;
244 }
245
dev_or_flags(struct udevice * dev,u32 or)246 static inline void dev_or_flags(struct udevice *dev, u32 or)
247 {
248 dev->flags_ |= or;
249 }
250
dev_bic_flags(struct udevice * dev,u32 bic)251 static inline void dev_bic_flags(struct udevice *dev, u32 bic)
252 {
253 dev->flags_ &= ~bic;
254 }
255 #endif /* OF_PLATDATA_RT */
256
257 /**
258 * dev_ofnode() - get the DT node reference associated with a udevice
259 *
260 * @dev: device to check
261 * Return: reference of the device's DT node
262 */
dev_ofnode(const struct udevice * dev)263 static inline __attribute_const__ ofnode dev_ofnode(const struct udevice *dev)
264 {
265 #if CONFIG_IS_ENABLED(OF_REAL)
266 return dev->node_;
267 #else
268 return ofnode_null();
269 #endif
270 }
271
272 /* Returns non-zero if the device is active (probed and not removed) */
273 #define device_active(dev) (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
274
275 #if CONFIG_IS_ENABLED(DM_DMA)
276 #define dev_set_dma_offset(_dev, _offset) _dev->dma_offset = _offset
277 #define dev_get_dma_offset(_dev) _dev->dma_offset
278 #else
279 #define dev_set_dma_offset(_dev, _offset)
280 #define dev_get_dma_offset(_dev) 0
281 #endif
282
dev_of_offset(const struct udevice * dev)283 static inline __attribute_const__ int dev_of_offset(const struct udevice *dev)
284 {
285 #if CONFIG_IS_ENABLED(OF_REAL)
286 return ofnode_to_offset(dev_ofnode(dev));
287 #else
288 return -1;
289 #endif
290 }
291
dev_has_ofnode(const struct udevice * dev)292 static inline __attribute_const__ bool dev_has_ofnode(const struct udevice *dev)
293 {
294 #if CONFIG_IS_ENABLED(OF_REAL)
295 return ofnode_valid(dev_ofnode(dev));
296 #else
297 return false;
298 #endif
299 }
300
dev_set_ofnode(struct udevice * dev,ofnode node)301 static inline void dev_set_ofnode(struct udevice *dev, ofnode node)
302 {
303 #if CONFIG_IS_ENABLED(OF_REAL)
304 dev->node_ = node;
305 #endif
306 }
307
dev_seq(const struct udevice * dev)308 static inline int dev_seq(const struct udevice *dev)
309 {
310 return dev->seq_;
311 }
312
313 /**
314 * struct udevice_id - Lists the compatible strings supported by a driver
315 * @compatible: Compatible string
316 * @data: Data for this compatible string
317 */
318 struct udevice_id {
319 const char *compatible;
320 ulong data;
321 };
322
323 #if CONFIG_IS_ENABLED(OF_REAL)
324 #define of_match_ptr(_ptr) (_ptr)
325 #else
326 #define of_match_ptr(_ptr) NULL
327 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
328
329 /**
330 * struct driver - A driver for a feature or peripheral
331 *
332 * This holds methods for setting up a new device, and also removing it.
333 * The device needs information to set itself up - this is provided either
334 * by plat or a device tree node (which we find by looking up
335 * matching compatible strings with of_match).
336 *
337 * Drivers all belong to a uclass, representing a class of devices of the
338 * same type. Common elements of the drivers can be implemented in the uclass,
339 * or the uclass can provide a consistent interface to the drivers within
340 * it.
341 *
342 * @name: Device name
343 * @id: Identifies the uclass we belong to
344 * @of_match: List of compatible strings to match, and any identifying data
345 * for each.
346 * @bind: Called to bind a device to its driver
347 * @probe: Called to probe a device, i.e. activate it
348 * @remove: Called to remove a device, i.e. de-activate it
349 * @unbind: Called to unbind a device from its driver
350 * @of_to_plat: Called before probe to decode device tree data
351 * @child_post_bind: Called after a new child has been bound
352 * @child_pre_probe: Called before a child device is probed. The device has
353 * memory allocated but it has not yet been probed.
354 * @child_post_remove: Called after a child device is removed. The device
355 * has memory allocated but its device_remove() method has been called.
356 * @priv_auto: If non-zero this is the size of the private data
357 * to be allocated in the device's ->priv pointer. If zero, then the driver
358 * is responsible for allocating any data required.
359 * @plat_auto: If non-zero this is the size of the
360 * platform data to be allocated in the device's ->plat pointer.
361 * This is typically only useful for device-tree-aware drivers (those with
362 * an of_match), since drivers which use plat will have the data
363 * provided in the U_BOOT_DRVINFO() instantiation.
364 * @per_child_auto: Each device can hold private data owned by
365 * its parent. If required this will be automatically allocated if this
366 * value is non-zero.
367 * @per_child_plat_auto: A bus likes to store information about
368 * its children. If non-zero this is the size of this data, to be allocated
369 * in the child's parent_plat pointer.
370 * @ops: Driver-specific operations. This is typically a list of function
371 * pointers defined by the driver, to implement driver functions required by
372 * the uclass.
373 * @flags: driver flags - see `DM_FLAG_...`
374 * @acpi_ops: Advanced Configuration and Power Interface (ACPI) operations,
375 * allowing the device to add things to the ACPI tables passed to Linux
376 */
377 struct driver {
378 char *name;
379 enum uclass_id id;
380 const struct udevice_id *of_match;
381 int (*bind)(struct udevice *dev);
382 int (*probe)(struct udevice *dev);
383 int (*remove)(struct udevice *dev);
384 int (*unbind)(struct udevice *dev);
385 int (*of_to_plat)(struct udevice *dev);
386 int (*child_post_bind)(struct udevice *dev);
387 int (*child_pre_probe)(struct udevice *dev);
388 int (*child_post_remove)(struct udevice *dev);
389 int priv_auto;
390 int plat_auto;
391 int per_child_auto;
392 int per_child_plat_auto;
393 const void *ops; /* driver-specific operations */
394 uint32_t flags;
395 #if CONFIG_IS_ENABLED(ACPIGEN)
396 struct acpi_ops *acpi_ops;
397 #endif
398 };
399
400 /**
401 * U_BOOT_DRIVER() - Declare a new U-Boot driver
402 * @__name: name of the driver
403 */
404 #define U_BOOT_DRIVER(__name) \
405 ll_entry_declare(struct driver, __name, driver)
406
407 /**
408 * DM_DRIVER_GET() - Get a pointer to a given driver
409 *
410 * This is useful in code for referencing a driver at build time.
411 * Before this is used, an extern U_BOOT_DRIVER() must have been
412 * declared.
413 *
414 * @__name: Name of the driver. This must be a valid C identifier,
415 * used by the linker_list
416 * Return: struct driver * for the driver
417 */
418 #define DM_DRIVER_GET(__name) \
419 ll_entry_get(struct driver, __name, driver)
420
421 /**
422 * DM_DRIVER_REF() - Get a reference to a driver
423 *
424 * This is useful in data structures and code for referencing a driver at
425 * build time. Before this is used, an extern U_BOOT_DRIVER() must have been
426 * declared.
427 * This is like DM_DRIVER_GET, but without the extra code, so it is suitable
428 * for putting into data structures.
429 *
430 * For example::
431 *
432 * extern U_BOOT_DRIVER(sandbox_fixed_clock);
433 * struct driver *drvs[] = {
434 * DM_DRIVER_REF(sandbox_fixed_clock),
435 * };
436 *
437 * @_name: Name of the driver. This must be a valid C identifier,
438 * used by the linker_list
439 * Return: struct driver * for the driver
440 */
441 #define DM_DRIVER_REF(_name) \
442 ll_entry_ref(struct driver, _name, driver)
443
444 /**
445 * DM_DRIVER_ALIAS() - Declare a macro to state an alias for a driver name
446 *
447 * This macro will produce no code but its information will be parsed by tools
448 * like dtoc
449 *
450 * @__name: name of driver
451 * @__alias: alias for the driver name
452 */
453 #define DM_DRIVER_ALIAS(__name, __alias)
454
455 /**
456 * DM_PHASE() - Declare a macro to indicate which phase of U-Boot this driver is for.
457 *
458 * This macro produces no code but its information will be parsed by dtoc. The
459 * macro can be only be used once in a driver. Put it within the U_BOOT_DRIVER()
460 * declaration, e.g.::
461 *
462 * U_BOOT_DRIVER(cpu) = {
463 * .name = ...
464 * ...
465 * DM_PHASE(tpl)
466 * };
467 *
468 * @_phase: Associated phase of U-Boot ("spl", "tpl")
469 */
470 #define DM_PHASE(_phase)
471
472 /**
473 * DM_HEADER() - Declare a macro to declare a header needed for a driver.
474 *
475 * Often the correct header can be found automatically, but only for struct
476 * declarations. For enums and #defines used in the driver declaration and
477 * declared in a different header from the structs, this macro must be used.
478 *
479 * This macro produces no code but its information will be parsed by dtoc. The
480 * macro can be used multiple times with different headers, for the same driver.
481 * Put it within the U_BOOT_DRIVER() declaration, e.g.::
482 *
483 * U_BOOT_DRIVER(cpu) = {
484 * .name = ...
485 * ...
486 * DM_HEADER(<asm/cpu.h>)
487 * };
488 *
489 * @_hdr: header needed for a driver
490 */
491 #define DM_HEADER(_hdr)
492
493 /**
494 * dev_get_plat() - Get the platform data for a device
495 *
496 * This checks that dev is not NULL, but no other checks for now
497 *
498 * @dev: Device to check
499 * Return: platform data, or NULL if none
500 */
501 void *dev_get_plat(const struct udevice *dev);
502
503 /**
504 * dev_get_parent_plat() - Get the parent platform data for a device
505 *
506 * This checks that dev is not NULL, but no other checks for now
507 *
508 * @dev: Device to check
509 * Return: parent's platform data, or NULL if none
510 */
511 void *dev_get_parent_plat(const struct udevice *dev);
512
513 /**
514 * dev_get_uclass_plat() - Get the uclass platform data for a device
515 *
516 * This checks that dev is not NULL, but no other checks for now
517 *
518 * @dev: Device to check
519 * Return: uclass's platform data, or NULL if none
520 */
521 void *dev_get_uclass_plat(const struct udevice *dev);
522
523 /**
524 * dev_get_priv() - Get the private data for a device
525 *
526 * This checks that dev is not NULL, but no other checks for now
527 *
528 * @dev: Device to check
529 * Return: private data, or NULL if none
530 */
531 void *dev_get_priv(const struct udevice *dev);
532
533 /**
534 * dev_get_parent_priv() - Get the parent private data for a device
535 *
536 * The parent private data is data stored in the device but owned by the
537 * parent. For example, a USB device may have parent data which contains
538 * information about how to talk to the device over USB.
539 *
540 * This checks that dev is not NULL, but no other checks for now
541 *
542 * @dev: Device to check
543 * Return: parent data, or NULL if none
544 */
545 void *dev_get_parent_priv(const struct udevice *dev);
546
547 /**
548 * dev_get_uclass_priv() - Get the private uclass data for a device
549 *
550 * This checks that dev is not NULL, but no other checks for now
551 *
552 * @dev: Device to check
553 * Return: private uclass data for this device, or NULL if none
554 */
555 void *dev_get_uclass_priv(const struct udevice *dev);
556
557 /**
558 * dev_get_attach_ptr() - Get the value of an attached pointed tag
559 *
560 * The tag is assumed to hold a pointer, if it exists
561 *
562 * @dev: Device to look at
563 * @tag: Tag to access
564 * @return value of tag, or NULL if there is no tag of this type
565 */
566 void *dev_get_attach_ptr(const struct udevice *dev, enum dm_tag_t tag);
567
568 /**
569 * dev_get_attach_size() - Get the size of an attached tag
570 *
571 * Core tags have an automatic-allocation mechanism where the allocated size is
572 * defined by the device, parent or uclass. This returns the size associated
573 * with a particular tag
574 *
575 * @dev: Device to look at
576 * @tag: Tag to access
577 * @return size of auto-allocated data, 0 if none
578 */
579 int dev_get_attach_size(const struct udevice *dev, enum dm_tag_t tag);
580
581 /**
582 * dev_get_parent() - Get the parent of a device
583 *
584 * @child: Child to check
585 * Return: parent of child, or NULL if this is the root device
586 */
587 struct udevice *dev_get_parent(const struct udevice *child);
588
589 /**
590 * dev_get_driver_data() - get the driver data used to bind a device
591 *
592 * When a device is bound using a device tree node, it matches a
593 * particular compatible string in struct udevice_id. This function
594 * returns the associated data value for that compatible string. This is
595 * the 'data' field in struct udevice_id.
596 *
597 * As an example, consider this structure::
598 *
599 * static const struct udevice_id tegra_i2c_ids[] = {
600 * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
601 * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
602 * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
603 * { }
604 * };
605 *
606 * When driver model finds a driver for this it will store the 'data' value
607 * corresponding to the compatible string it matches. This function returns
608 * that value. This allows the driver to handle several variants of a device.
609 *
610 * For USB devices, this is the driver_info field in struct usb_device_id.
611 *
612 * @dev: Device to check
613 * Return: driver data (0 if none is provided)
614 */
615 ulong dev_get_driver_data(const struct udevice *dev);
616
617 /**
618 * dev_get_driver_ops() - get the device's driver's operations
619 *
620 * This checks that dev is not NULL, and returns the pointer to device's
621 * driver's operations.
622 *
623 * @dev: Device to check
624 * Return: void pointer to driver's operations or NULL for NULL-dev or NULL-ops
625 */
626 const void *dev_get_driver_ops(const struct udevice *dev);
627
628 /**
629 * device_get_uclass_id() - return the uclass ID of a device
630 *
631 * @dev: Device to check
632 * Return: uclass ID for the device
633 */
634 enum uclass_id device_get_uclass_id(const struct udevice *dev);
635
636 /**
637 * dev_get_uclass_name() - return the uclass name of a device
638 *
639 * This checks that dev is not NULL.
640 *
641 * @dev: Device to check
642 * Return: pointer to the uclass name for the device
643 */
644 const char *dev_get_uclass_name(const struct udevice *dev);
645
646 /**
647 * device_get_child() - Get the child of a device by index
648 *
649 * Returns the numbered child, 0 being the first. This does not use
650 * sequence numbers, only the natural order.
651 *
652 * @parent: Parent device to check
653 * @index: Child index
654 * @devp: Returns pointer to device
655 * Return:
656 * 0 if OK, -ENODEV if no such device, other error if the device fails to probe
657 */
658 int device_get_child(const struct udevice *parent, int index,
659 struct udevice **devp);
660
661 /**
662 * device_get_child_count() - Get the child count of a device
663 *
664 * Returns the number of children to a device.
665 *
666 * @parent: Parent device to check
667 */
668 int device_get_child_count(const struct udevice *parent);
669
670 /**
671 * device_get_decendent_count() - Get the total number of decendents of a device
672 *
673 * Returns the total number of decendents, including all children
674 *
675 * @parent: Parent device to check
676 */
677 int device_get_decendent_count(const struct udevice *parent);
678
679 /**
680 * device_find_child_by_seq() - Find a child device based on a sequence
681 *
682 * This searches for a device with the given seq.
683 *
684 * @parent: Parent device
685 * @seq: Sequence number to find (0=first)
686 * @devp: Returns pointer to device (there is only one per for each seq).
687 * Set to NULL if none is found
688 * Return: 0 if OK, -ENODEV if not found
689 */
690 int device_find_child_by_seq(const struct udevice *parent, int seq,
691 struct udevice **devp);
692
693 /**
694 * device_get_child_by_seq() - Get a child device based on a sequence
695 *
696 * If an active device has this sequence it will be returned. If there is no
697 * such device then this will check for a device that is requesting this
698 * sequence.
699 *
700 * The device is probed to activate it ready for use.
701 *
702 * @parent: Parent device
703 * @seq: Sequence number to find (0=first)
704 * @devp: Returns pointer to device (there is only one per for each seq)
705 * Set to NULL if none is found
706 * Return: 0 if OK, -ve on error
707 */
708 int device_get_child_by_seq(const struct udevice *parent, int seq,
709 struct udevice **devp);
710
711 /**
712 * device_find_child_by_of_offset() - Find a child device based on FDT offset
713 *
714 * Locates a child device by its device tree offset.
715 *
716 * @parent: Parent device
717 * @of_offset: Device tree offset to find
718 * @devp: Returns pointer to device if found, otherwise this is set to NULL
719 * Return: 0 if OK, -ve on error
720 */
721 int device_find_child_by_of_offset(const struct udevice *parent, int of_offset,
722 struct udevice **devp);
723
724 /**
725 * device_get_child_by_of_offset() - Get a child device based on FDT offset
726 *
727 * Locates a child device by its device tree offset.
728 *
729 * The device is probed to activate it ready for use.
730 *
731 * @parent: Parent device
732 * @of_offset: Device tree offset to find
733 * @devp: Returns pointer to device if found, otherwise this is set to NULL
734 * Return: 0 if OK, -ve on error
735 */
736 int device_get_child_by_of_offset(const struct udevice *parent, int of_offset,
737 struct udevice **devp);
738
739 /**
740 * device_find_global_by_ofnode() - Get a device based on ofnode
741 *
742 * Locates a device by its device tree ofnode, searching globally throughout
743 * the all driver model devices.
744 *
745 * The device is NOT probed
746 *
747 * @node: Device tree ofnode to find
748 * @devp: Returns pointer to device if found, otherwise this is set to NULL
749 * Return: 0 if OK, -ve on error
750 */
751
752 int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
753
754 /**
755 * device_get_global_by_ofnode() - Get a device based on ofnode
756 *
757 * Locates a device by its device tree ofnode, searching globally throughout
758 * the all driver model devices.
759 *
760 * The device is probed to activate it ready for use.
761 *
762 * @node: Device tree ofnode to find
763 * @devp: Returns pointer to device if found, otherwise this is set to NULL
764 * Return: 0 if OK, -ve on error
765 */
766 int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
767
768 /**
769 * device_get_by_ofplat_idx() - Get a device based on of-platdata index
770 *
771 * Locates a device by either its struct driver_info index, or its
772 * struct udevice index. The latter is used with OF_PLATDATA_INST, since we have
773 * a list of build-time instantiated struct udevice records, The former is used
774 * with !OF_PLATDATA_INST since in that case we have a list of
775 * struct driver_info records.
776 *
777 * The index number is written into the idx field of struct phandle_1_arg, etc.
778 * It is the position of this driver_info/udevice in its linker list.
779 *
780 * The device is probed to activate it ready for use.
781 *
782 * @idx: Index number of the driver_info/udevice structure (0=first)
783 * @devp: Returns pointer to device if found, otherwise this is set to NULL
784 * Return: 0 if OK, -ve on error
785 */
786 int device_get_by_ofplat_idx(uint idx, struct udevice **devp);
787
788 /**
789 * device_find_first_child() - Find the first child of a device
790 *
791 * @parent: Parent device to search
792 * @devp: Returns first child device, or NULL if none
793 * Return: 0
794 */
795 int device_find_first_child(const struct udevice *parent,
796 struct udevice **devp);
797
798 /**
799 * device_find_next_child() - Find the next child of a device
800 *
801 * @devp: Pointer to previous child device on entry. Returns pointer to next
802 * child device, or NULL if none
803 * Return: 0
804 */
805 int device_find_next_child(struct udevice **devp);
806
807 /**
808 * device_find_first_inactive_child() - Find the first inactive child
809 *
810 * This is used to locate an existing child of a device which is of a given
811 * uclass.
812 *
813 * The device is NOT probed
814 *
815 * @parent: Parent device to search
816 * @uclass_id: Uclass to look for
817 * @devp: Returns device found, if any, else NULL
818 * Return: 0 if found, else -ENODEV
819 */
820 int device_find_first_inactive_child(const struct udevice *parent,
821 enum uclass_id uclass_id,
822 struct udevice **devp);
823
824 /**
825 * device_find_first_child_by_uclass() - Find the first child of a device in uc
826 *
827 * @parent: Parent device to search
828 * @uclass_id: Uclass to look for
829 * @devp: Returns first child device in that uclass, if any, else NULL
830 * Return: 0 if found, else -ENODEV
831 */
832 int device_find_first_child_by_uclass(const struct udevice *parent,
833 enum uclass_id uclass_id,
834 struct udevice **devp);
835
836 /**
837 * device_find_child_by_namelen() - Find a child by device name
838 *
839 * @parent: Parent device to search
840 * @name: Name to look for
841 * @len: Length of the name
842 * @devp: Returns device found, if any
843 * Return: 0 if found, else -ENODEV
844 */
845 int device_find_child_by_namelen(const struct udevice *parent, const char *name,
846 int len, struct udevice **devp);
847
848 /**
849 * device_find_child_by_name() - Find a child by device name
850 *
851 * @parent: Parent device to search
852 * @name: Name to look for
853 * @devp: Returns device found, if any
854 * Return: 0 if found, else -ENODEV
855 */
856 int device_find_child_by_name(const struct udevice *parent, const char *name,
857 struct udevice **devp);
858
859 /**
860 * device_first_child_ofdata_err() - Find the first child and reads its plat
861 *
862 * The of_to_plat() method is called on the child before it is returned,
863 * but the child is not probed.
864 *
865 * @parent: Parent to check
866 * @devp: Returns child that was found, if any
867 * Return: 0 on success, -ENODEV if no children, other -ve on error
868 */
869 int device_first_child_ofdata_err(struct udevice *parent,
870 struct udevice **devp);
871
872 /*
873 * device_next_child_ofdata_err() - Find the next child and read its plat
874 *
875 * The of_to_plat() method is called on the child before it is returned,
876 * but the child is not probed.
877 *
878 * @devp: On entry, points to the previous child; on exit returns the child that
879 * was found, if any
880 * Return: 0 on success, -ENODEV if no children, other -ve on error
881 */
882 int device_next_child_ofdata_err(struct udevice **devp);
883
884 /**
885 * device_first_child_err() - Get the first child of a device
886 *
887 * The device returned is probed if necessary, and ready for use
888 *
889 * @parent: Parent device to search
890 * @devp: Returns device found, if any
891 * Return: 0 if found, -ENODEV if not, -ve error if device failed to probe
892 */
893 int device_first_child_err(struct udevice *parent, struct udevice **devp);
894
895 /**
896 * device_next_child_err() - Get the next child of a parent device
897 *
898 * The device returned is probed if necessary, and ready for use
899 *
900 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
901 * to the next sibling if no error occurred
902 * Return: 0 if found, -ENODEV if not, -ve error if device failed to probe
903 */
904 int device_next_child_err(struct udevice **devp);
905
906 /**
907 * device_has_children() - check if a device has any children
908 *
909 * @dev: Device to check
910 * Return: true if the device has one or more children
911 */
912 bool device_has_children(const struct udevice *dev);
913
914 /**
915 * device_has_active_children() - check if a device has any active children
916 *
917 * @dev: Device to check
918 * Return: true if the device has one or more children and at least one of
919 * them is active (probed).
920 */
921 bool device_has_active_children(const struct udevice *dev);
922
923 /**
924 * device_is_last_sibling() - check if a device is the last sibling
925 *
926 * This function can be useful for display purposes, when special action needs
927 * to be taken when displaying the last sibling. This can happen when a tree
928 * view of devices is being displayed.
929 *
930 * @dev: Device to check
931 * Return: true if there are no more siblings after this one - i.e. is it
932 * last in the list.
933 */
934 bool device_is_last_sibling(const struct udevice *dev);
935
936 /**
937 * device_set_name() - set the name of a device
938 *
939 * This must be called in the device's bind() method and no later. Normally
940 * this is unnecessary but for probed devices which don't get a useful name
941 * this function can be helpful.
942 *
943 * The name is allocated and will be freed automatically when the device is
944 * unbound.
945 *
946 * @dev: Device to update
947 * @name: New name (this string is allocated new memory and attached to
948 * the device)
949 * Return: 0 if OK, -ENOMEM if there is not enough memory to allocate the
950 * string
951 */
952 int device_set_name(struct udevice *dev, const char *name);
953
954 /**
955 * device_set_name_alloced() - note that a device name is allocated
956 *
957 * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
958 * unbound the name will be freed. This avoids memory leaks.
959 *
960 * @dev: Device to update
961 */
962 void device_set_name_alloced(struct udevice *dev);
963
964 /**
965 * device_is_compatible() - check if the device is compatible with the compat
966 *
967 * This allows to check whether the device is comaptible with the compat.
968 *
969 * @dev: udevice pointer for which compatible needs to be verified.
970 * @compat: Compatible string which needs to verified in the given
971 * device
972 * Return: true if OK, false if the compatible is not found
973 */
974 bool device_is_compatible(const struct udevice *dev, const char *compat);
975
976 /**
977 * of_machine_is_compatible() - check if the machine is compatible with
978 * the compat
979 *
980 * This allows to check whether the machine is comaptible with the compat.
981 *
982 * @compat: Compatible string which needs to verified
983 * Return: true if OK, false if the compatible is not found
984 */
985 bool of_machine_is_compatible(const char *compat);
986
987 /**
988 * dev_disable_by_path() - Disable a device given its device tree path
989 *
990 * @path: The device tree path identifying the device to be disabled
991 * Return: 0 on success, -ve on error
992 */
993 int dev_disable_by_path(const char *path);
994
995 /**
996 * dev_enable_by_path() - Enable a device given its device tree path
997 *
998 * @path: The device tree path identifying the device to be enabled
999 * Return: 0 on success, -ve on error
1000 */
1001 int dev_enable_by_path(const char *path);
1002
1003 /**
1004 * device_is_on_pci_bus - Test if a device is on a PCI bus
1005 *
1006 * @dev: device to test
1007 * Return: true if it is on a PCI bus, false otherwise
1008 */
device_is_on_pci_bus(const struct udevice * dev)1009 static inline bool device_is_on_pci_bus(const struct udevice *dev)
1010 {
1011 return CONFIG_IS_ENABLED(PCI) && dev->parent &&
1012 device_get_uclass_id(dev->parent) == UCLASS_PCI;
1013 }
1014
1015 /**
1016 * device_foreach_child_safe() - iterate through child devices safely
1017 *
1018 * This allows the @pos child to be removed in the loop if required.
1019 *
1020 * @pos: struct udevice * for the current device
1021 * @next: struct udevice * for the next device
1022 * @parent: parent device to scan
1023 */
1024 #define device_foreach_child_safe(pos, next, parent) \
1025 list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
1026
1027 /**
1028 * device_foreach_child() - iterate through child devices
1029 *
1030 * @pos: struct udevice * for the current device
1031 * @parent: parent device to scan
1032 */
1033 #define device_foreach_child(pos, parent) \
1034 list_for_each_entry(pos, &parent->child_head, sibling_node)
1035
1036 /**
1037 * device_foreach_child_of_to_plat() - iterate through children
1038 *
1039 * This stops when it gets an error, with @pos set to the device that failed to
1040 * read ofdata.
1041 *
1042 * This creates a for() loop which works through the available children of
1043 * a device in order from start to end. Device ofdata is read by calling
1044 * device_of_to_plat() on each one. The devices are not probed.
1045 *
1046 * @pos: struct udevice * for the current device
1047 * @parent: parent device to scan
1048 */
1049 #define device_foreach_child_of_to_plat(pos, parent) \
1050 for (int _ret = device_first_child_ofdata_err(parent, &pos); !_ret; \
1051 _ret = device_next_child_ofdata_err(&pos))
1052
1053 /**
1054 * device_foreach_child_probe() - iterate through children, probing them
1055 *
1056 * This creates a for() loop which works through the available children of
1057 * a device in order from start to end. Devices are probed if necessary,
1058 * and ready for use.
1059 *
1060 * This stops when it gets an error, with @pos set to the device that failed to
1061 * probe
1062 *
1063 * @pos: struct udevice * for the current device
1064 * @parent: parent device to scan
1065 */
1066 #define device_foreach_child_probe(pos, parent) \
1067 for (int _ret = device_first_child_err(parent, &pos); !_ret; \
1068 _ret = device_next_child_err(&pos))
1069
1070 /**
1071 * dm_scan_fdt_dev() - Bind child device in the device tree
1072 *
1073 * This handles device which have sub-nodes in the device tree. It scans all
1074 * sub-nodes and binds drivers for each node where a driver can be found.
1075 *
1076 * If this is called prior to relocation, only pre-relocation devices will be
1077 * bound (those marked with bootph-all in the device tree, or where
1078 * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
1079 * be bound.
1080 *
1081 * @dev: Device to scan
1082 * Return: 0 if OK, -ve on error
1083 */
1084 int dm_scan_fdt_dev(struct udevice *dev);
1085
1086 #endif
1087