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/uclass-id.h>
15 #include <fdtdec.h>
16 #include <linker_lists.h>
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 #include <linux/printk.h>
20
21 struct driver_info;
22
23 /* Driver is active (probed). Cleared when it is removed */
24 #define DM_FLAG_ACTIVATED (1 << 0)
25
26 /* DM is responsible for allocating and freeing plat */
27 #define DM_FLAG_ALLOC_PDATA (1 << 1)
28
29 /* DM should init this device prior to relocation */
30 #define DM_FLAG_PRE_RELOC (1 << 2)
31
32 /* DM is responsible for allocating and freeing parent_plat */
33 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
34
35 /* DM is responsible for allocating and freeing uclass_plat */
36 #define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4)
37
38 /* Allocate driver private data on a DMA boundary */
39 #define DM_FLAG_ALLOC_PRIV_DMA (1 << 5)
40
41 /* Device is bound */
42 #define DM_FLAG_BOUND (1 << 6)
43
44 /* Device name is allocated and should be freed on unbind() */
45 #define DM_FLAG_NAME_ALLOCED (1 << 7)
46
47 /* Device has platform data provided by of-platdata */
48 #define DM_FLAG_OF_PLATDATA (1 << 8)
49
50 /*
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
54 * (U-Boot exit)
55 */
56 #define DM_FLAG_ACTIVE_DMA (1 << 9)
57
58 /*
59 * Call driver remove function to do some final configuration, before
60 * U-Boot exits and the OS is started
61 */
62 #define DM_FLAG_OS_PREPARE (1 << 10)
63
64 /* DM does not enable/disable the power domains corresponding to this device */
65 #define DM_FLAG_DEFAULT_PD_CTRL_OFF (1 << 11)
66
67 /* Driver plat has been read. Cleared when the device is removed */
68 #define DM_FLAG_PLATDATA_VALID (1 << 12)
69
70 /*
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.
73 */
74 #define DM_FLAG_LEAVE_PD_ON (1 << 13)
75
76 /*
77 * Device is vital to the operation of other devices. It is possible to remove
78 * removed this device after all regular devices are removed. This is useful
79 * e.g. for clock, which need to be active during the device-removal phase.
80 */
81 #define DM_FLAG_VITAL (1 << 14)
82
83 /*
84 * One or multiple of these flags are passed to device_remove() so that
85 * a selective device removal as specified by the remove-stage and the
86 * driver flags can be done.
87 *
88 * DO NOT use these flags in your driver's @flags value...
89 * use the above DM_FLAG_... values instead
90 */
91 enum {
92 /* Normal remove, remove all devices */
93 DM_REMOVE_NORMAL = 1 << 0,
94
95 /* Remove devices with active DMA */
96 DM_REMOVE_ACTIVE_DMA = DM_FLAG_ACTIVE_DMA,
97
98 /* Remove devices which need some final OS preparation steps */
99 DM_REMOVE_OS_PREPARE = DM_FLAG_OS_PREPARE,
100
101 /* Remove only devices that are not marked vital */
102 DM_REMOVE_NON_VITAL = DM_FLAG_VITAL,
103
104 /* Remove devices with any active flag */
105 DM_REMOVE_ACTIVE_ALL = DM_REMOVE_ACTIVE_DMA | DM_REMOVE_OS_PREPARE,
106
107 /* Don't power down any attached power domains */
108 DM_REMOVE_NO_PD = 1 << 1,
109 };
110
111 /**
112 * struct udevice - An instance of a driver
113 *
114 * This holds information about a device, which is a driver bound to a
115 * particular port or peripheral (essentially a driver instance).
116 *
117 * A device will come into existence through a 'bind' call, either due to
118 * a U_BOOT_DRVINFO() macro (in which case plat is non-NULL) or a node
119 * in the device tree (in which case of_offset is >= 0). In the latter case
120 * we translate the device tree information into plat in a function
121 * implemented by the driver of_to_plat method (called just before the
122 * probe method if the device has a device tree node.
123 *
124 * All three of plat, priv and uclass_priv can be allocated by the
125 * driver, or you can use the auto members of struct driver and
126 * struct uclass_driver to have driver model do this automatically.
127 *
128 * @driver: The driver used by this device
129 * @name: Name of device, typically the FDT node name
130 * @plat_: Configuration data for this device (do not access outside driver
131 * model)
132 * @parent_plat_: The parent bus's configuration data for this device (do not
133 * access outside driver model)
134 * @uclass_plat_: The uclass's configuration data for this device (do not access
135 * outside driver model)
136 * @driver_data: Driver data word for the entry that matched this device with
137 * its driver
138 * @parent: Parent of this device, or NULL for the top level device
139 * @priv_: Private data for this device (do not access outside driver model)
140 * @uclass: Pointer to uclass for this device
141 * @uclass_priv_: The uclass's private data for this device (do not access
142 * outside driver model)
143 * @parent_priv_: The parent's private data for this device (do not access
144 * outside driver model)
145 * @uclass_node: Used by uclass to link its devices
146 * @child_head: List of children of this device
147 * @sibling_node: Next device in list of all devices
148 * @flags_: Flags for this device DM_FLAG_... (do not access outside driver
149 * model)
150 * @seq_: Allocated sequence number for this device (-1 = none). This is set up
151 * when the device is bound and is unique within the device's uclass. If the
152 * device has an alias in the devicetree then that is used to set the sequence
153 * number. Otherwise, the next available number is used. Sequence numbers are
154 * used by certain commands that need device to be numbered (e.g. 'mmc dev').
155 * (do not access outside driver model)
156 * @node_: Reference to device tree node for this device (do not access outside
157 * driver model)
158 * @devres_head: List of memory allocations associated with this device.
159 * When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
160 * add to this list. Memory so-allocated will be freed
161 * automatically when the device is removed / unbound
162 * @dma_offset: Offset between the physical address space (CPU's) and the
163 * device's bus address space
164 */
165 struct udevice {
166 const struct driver *driver;
167 const char *name;
168 void *plat_;
169 void *parent_plat_;
170 void *uclass_plat_;
171 ulong driver_data;
172 struct udevice *parent;
173 void *priv_;
174 struct uclass *uclass;
175 void *uclass_priv_;
176 void *parent_priv_;
177 struct list_head uclass_node;
178 struct list_head child_head;
179 struct list_head sibling_node;
180 #if !CONFIG_IS_ENABLED(OF_PLATDATA_RT)
181 u32 flags_;
182 #endif
183 int seq_;
184 #if CONFIG_IS_ENABLED(OF_REAL)
185 ofnode node_;
186 #endif
187 #ifdef CONFIG_DEVRES
188 struct list_head devres_head;
189 #endif
190 #if CONFIG_IS_ENABLED(DM_DMA)
191 ulong dma_offset;
192 #endif
193 };
194
195 /**
196 * udevice_rt - runtime information set up by U-Boot
197 *
198 * This is only used with OF_PLATDATA_RT
199 *
200 * There is one of these for every udevice in the linker list, indexed by
201 * the udevice_info idx value.
202 *
203 * @flags_: Flags for this device DM_FLAG_... (do not access outside driver
204 * model)
205 */
206 struct udevice_rt {
207 u32 flags_;
208 };
209
210 /* Maximum sequence number supported and associated string length */
211 #define DM_MAX_SEQ 999
212 #define DM_MAX_SEQ_STR 3
213
214 /* Returns the operations for a device */
215 #define device_get_ops(dev) (dev->driver->ops)
216
217 #if CONFIG_IS_ENABLED(OF_PLATDATA_RT)
218 u32 dev_get_flags(const struct udevice *dev);
219 void dev_or_flags(const struct udevice *dev, u32 or);
220 void dev_bic_flags(const struct udevice *dev, u32 bic);
221 #else
dev_get_flags(const struct udevice * dev)222 static inline u32 dev_get_flags(const struct udevice *dev)
223 {
224 return dev->flags_;
225 }
226
dev_or_flags(struct udevice * dev,u32 or)227 static inline void dev_or_flags(struct udevice *dev, u32 or)
228 {
229 dev->flags_ |= or;
230 }
231
dev_bic_flags(struct udevice * dev,u32 bic)232 static inline void dev_bic_flags(struct udevice *dev, u32 bic)
233 {
234 dev->flags_ &= ~bic;
235 }
236 #endif /* OF_PLATDATA_RT */
237
238 /**
239 * dev_ofnode() - get the DT node reference associated with a udevice
240 *
241 * @dev: device to check
242 * @return reference of the the device's DT node
243 */
dev_ofnode(const struct udevice * dev)244 static inline ofnode dev_ofnode(const struct udevice *dev)
245 {
246 #if CONFIG_IS_ENABLED(OF_REAL)
247 return dev->node_;
248 #else
249 return ofnode_null();
250 #endif
251 }
252
253 /* Returns non-zero if the device is active (probed and not removed) */
254 #define device_active(dev) (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
255
256 #if CONFIG_IS_ENABLED(DM_DMA)
257 #define dev_set_dma_offset(_dev, _offset) _dev->dma_offset = _offset
258 #define dev_get_dma_offset(_dev) _dev->dma_offset
259 #else
260 #define dev_set_dma_offset(_dev, _offset)
261 #define dev_get_dma_offset(_dev) 0
262 #endif
263
dev_of_offset(const struct udevice * dev)264 static inline int dev_of_offset(const struct udevice *dev)
265 {
266 #if CONFIG_IS_ENABLED(OF_REAL)
267 return ofnode_to_offset(dev_ofnode(dev));
268 #else
269 return -1;
270 #endif
271 }
272
dev_has_ofnode(const struct udevice * dev)273 static inline bool dev_has_ofnode(const struct udevice *dev)
274 {
275 #if CONFIG_IS_ENABLED(OF_REAL)
276 return ofnode_valid(dev_ofnode(dev));
277 #else
278 return false;
279 #endif
280 }
281
dev_set_ofnode(struct udevice * dev,ofnode node)282 static inline void dev_set_ofnode(struct udevice *dev, ofnode node)
283 {
284 #if CONFIG_IS_ENABLED(OF_REAL)
285 dev->node_ = node;
286 #endif
287 }
288
dev_seq(const struct udevice * dev)289 static inline int dev_seq(const struct udevice *dev)
290 {
291 return dev->seq_;
292 }
293
294 /**
295 * struct udevice_id - Lists the compatible strings supported by a driver
296 * @compatible: Compatible string
297 * @data: Data for this compatible string
298 */
299 struct udevice_id {
300 const char *compatible;
301 ulong data;
302 };
303
304 #if CONFIG_IS_ENABLED(OF_REAL)
305 #define of_match_ptr(_ptr) (_ptr)
306 #else
307 #define of_match_ptr(_ptr) NULL
308 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
309
310 /**
311 * struct driver - A driver for a feature or peripheral
312 *
313 * This holds methods for setting up a new device, and also removing it.
314 * The device needs information to set itself up - this is provided either
315 * by plat or a device tree node (which we find by looking up
316 * matching compatible strings with of_match).
317 *
318 * Drivers all belong to a uclass, representing a class of devices of the
319 * same type. Common elements of the drivers can be implemented in the uclass,
320 * or the uclass can provide a consistent interface to the drivers within
321 * it.
322 *
323 * @name: Device name
324 * @id: Identifies the uclass we belong to
325 * @of_match: List of compatible strings to match, and any identifying data
326 * for each.
327 * @bind: Called to bind a device to its driver
328 * @probe: Called to probe a device, i.e. activate it
329 * @remove: Called to remove a device, i.e. de-activate it
330 * @unbind: Called to unbind a device from its driver
331 * @of_to_plat: Called before probe to decode device tree data
332 * @child_post_bind: Called after a new child has been bound
333 * @child_pre_probe: Called before a child device is probed. The device has
334 * memory allocated but it has not yet been probed.
335 * @child_post_remove: Called after a child device is removed. The device
336 * has memory allocated but its device_remove() method has been called.
337 * @priv_auto: If non-zero this is the size of the private data
338 * to be allocated in the device's ->priv pointer. If zero, then the driver
339 * is responsible for allocating any data required.
340 * @plat_auto: If non-zero this is the size of the
341 * platform data to be allocated in the device's ->plat pointer.
342 * This is typically only useful for device-tree-aware drivers (those with
343 * an of_match), since drivers which use plat will have the data
344 * provided in the U_BOOT_DRVINFO() instantiation.
345 * @per_child_auto: Each device can hold private data owned by
346 * its parent. If required this will be automatically allocated if this
347 * value is non-zero.
348 * @per_child_plat_auto: A bus likes to store information about
349 * its children. If non-zero this is the size of this data, to be allocated
350 * in the child's parent_plat pointer.
351 * @ops: Driver-specific operations. This is typically a list of function
352 * pointers defined by the driver, to implement driver functions required by
353 * the uclass.
354 * @flags: driver flags - see DM_FLAGS_...
355 * @acpi_ops: Advanced Configuration and Power Interface (ACPI) operations,
356 * allowing the device to add things to the ACPI tables passed to Linux
357 */
358 struct driver {
359 char *name;
360 enum uclass_id id;
361 const struct udevice_id *of_match;
362 int (*bind)(struct udevice *dev);
363 int (*probe)(struct udevice *dev);
364 int (*remove)(struct udevice *dev);
365 int (*unbind)(struct udevice *dev);
366 int (*of_to_plat)(struct udevice *dev);
367 int (*child_post_bind)(struct udevice *dev);
368 int (*child_pre_probe)(struct udevice *dev);
369 int (*child_post_remove)(struct udevice *dev);
370 int priv_auto;
371 int plat_auto;
372 int per_child_auto;
373 int per_child_plat_auto;
374 const void *ops; /* driver-specific operations */
375 uint32_t flags;
376 #if CONFIG_IS_ENABLED(ACPIGEN)
377 struct acpi_ops *acpi_ops;
378 #endif
379 };
380
381 /* Declare a new U-Boot driver */
382 #define U_BOOT_DRIVER(__name) \
383 ll_entry_declare(struct driver, __name, driver)
384
385 /* Get a pointer to a given driver */
386 #define DM_DRIVER_GET(__name) \
387 ll_entry_get(struct driver, __name, driver)
388
389 /**
390 * DM_DRIVER_REF() - Get a reference to a driver
391 *
392 * This is useful in data structures and code for referencing a driver at
393 * build time. Before this is used, an extern U_BOOT_DRIVER() must have been
394 * declared.
395 *
396 * For example:
397 *
398 * extern U_BOOT_DRIVER(sandbox_fixed_clock);
399 *
400 * struct driver *drvs[] = {
401 * DM_DRIVER_REF(sandbox_fixed_clock),
402 * };
403 *
404 * @_name: Name of the driver. This must be a valid C identifier, used by the
405 * linker_list
406 * @returns struct driver * for the driver
407 */
408 #define DM_DRIVER_REF(_name) \
409 ll_entry_ref(struct driver, _name, driver)
410
411 /**
412 * Declare a macro to state a alias for a driver name. This macro will
413 * produce no code but its information will be parsed by tools like
414 * dtoc
415 */
416 #define DM_DRIVER_ALIAS(__name, __alias)
417
418 /**
419 * Declare a macro to indicate which phase of U-Boot this driver is fore.
420 *
421 *
422 * This macro produces no code but its information will be parsed by dtoc. The
423 * macro can be only be used once in a driver. Put it within the U_BOOT_DRIVER()
424 * declaration, e.g.:
425 *
426 * U_BOOT_DRIVER(cpu) = {
427 * .name = ...
428 * ...
429 * DM_PHASE(tpl)
430 * };
431 */
432 #define DM_PHASE(_phase)
433
434 /**
435 * Declare a macro to declare a header needed for a driver. Often the correct
436 * header can be found automatically, but only for struct declarations. For
437 * enums and #defines used in the driver declaration and declared in a different
438 * header from the structs, this macro must be used.
439 *
440 * This macro produces no code but its information will be parsed by dtoc. The
441 * macro can be used multiple times with different headers, for the same driver.
442 * Put it within the U_BOOT_DRIVER() declaration, e.g.:
443 *
444 * U_BOOT_DRIVER(cpu) = {
445 * .name = ...
446 * ...
447 * DM_HEADER(<asm/cpu.h>)
448 * };
449 */
450 #define DM_HEADER(_hdr)
451
452 /**
453 * dev_get_plat() - Get the platform data for a device
454 *
455 * This checks that dev is not NULL, but no other checks for now
456 *
457 * @dev Device to check
458 * @return platform data, or NULL if none
459 */
460 void *dev_get_plat(const struct udevice *dev);
461
462 /**
463 * dev_get_parent_plat() - Get the parent platform data for a device
464 *
465 * This checks that dev is not NULL, but no other checks for now
466 *
467 * @dev Device to check
468 * @return parent's platform data, or NULL if none
469 */
470 void *dev_get_parent_plat(const struct udevice *dev);
471
472 /**
473 * dev_get_uclass_plat() - Get the uclass platform data for a device
474 *
475 * This checks that dev is not NULL, but no other checks for now
476 *
477 * @dev Device to check
478 * @return uclass's platform data, or NULL if none
479 */
480 void *dev_get_uclass_plat(const struct udevice *dev);
481
482 /**
483 * dev_get_priv() - Get the private data for a device
484 *
485 * This checks that dev is not NULL, but no other checks for now
486 *
487 * @dev Device to check
488 * @return private data, or NULL if none
489 */
490 void *dev_get_priv(const struct udevice *dev);
491
492 /**
493 * dev_get_parent_priv() - Get the parent private data for a device
494 *
495 * The parent private data is data stored in the device but owned by the
496 * parent. For example, a USB device may have parent data which contains
497 * information about how to talk to the device over USB.
498 *
499 * This checks that dev is not NULL, but no other checks for now
500 *
501 * @dev Device to check
502 * @return parent data, or NULL if none
503 */
504 void *dev_get_parent_priv(const struct udevice *dev);
505
506 /**
507 * dev_get_uclass_priv() - Get the private uclass data for a device
508 *
509 * This checks that dev is not NULL, but no other checks for now
510 *
511 * @dev Device to check
512 * @return private uclass data for this device, or NULL if none
513 */
514 void *dev_get_uclass_priv(const struct udevice *dev);
515
516 /**
517 * struct dev_get_parent() - Get the parent of a device
518 *
519 * @child: Child to check
520 * @return parent of child, or NULL if this is the root device
521 */
522 struct udevice *dev_get_parent(const struct udevice *child);
523
524 /**
525 * dev_get_driver_data() - get the driver data used to bind a device
526 *
527 * When a device is bound using a device tree node, it matches a
528 * particular compatible string in struct udevice_id. This function
529 * returns the associated data value for that compatible string. This is
530 * the 'data' field in struct udevice_id.
531 *
532 * As an example, consider this structure:
533 * static const struct udevice_id tegra_i2c_ids[] = {
534 * { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
535 * { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
536 * { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
537 * { }
538 * };
539 *
540 * When driver model finds a driver for this it will store the 'data' value
541 * corresponding to the compatible string it matches. This function returns
542 * that value. This allows the driver to handle several variants of a device.
543 *
544 * For USB devices, this is the driver_info field in struct usb_device_id.
545 *
546 * @dev: Device to check
547 * @return driver data (0 if none is provided)
548 */
549 ulong dev_get_driver_data(const struct udevice *dev);
550
551 /**
552 * dev_get_driver_ops() - get the device's driver's operations
553 *
554 * This checks that dev is not NULL, and returns the pointer to device's
555 * driver's operations.
556 *
557 * @dev: Device to check
558 * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
559 */
560 const void *dev_get_driver_ops(const struct udevice *dev);
561
562 /**
563 * device_get_uclass_id() - return the uclass ID of a device
564 *
565 * @dev: Device to check
566 * @return uclass ID for the device
567 */
568 enum uclass_id device_get_uclass_id(const struct udevice *dev);
569
570 /**
571 * dev_get_uclass_name() - return the uclass name of a device
572 *
573 * This checks that dev is not NULL.
574 *
575 * @dev: Device to check
576 * @return pointer to the uclass name for the device
577 */
578 const char *dev_get_uclass_name(const struct udevice *dev);
579
580 /**
581 * device_get_child() - Get the child of a device by index
582 *
583 * Returns the numbered child, 0 being the first. This does not use
584 * sequence numbers, only the natural order.
585 *
586 * @dev: Parent device to check
587 * @index: Child index
588 * @devp: Returns pointer to device
589 * @return 0 if OK, -ENODEV if no such device, other error if the device fails
590 * to probe
591 */
592 int device_get_child(const struct udevice *parent, int index,
593 struct udevice **devp);
594
595 /**
596 * device_get_child_count() - Get the available child count of a device
597 *
598 * Returns the number of children to a device.
599 *
600 * @parent: Parent device to check
601 */
602 int device_get_child_count(const struct udevice *parent);
603
604 /**
605 * device_find_child_by_seq() - Find a child device based on a sequence
606 *
607 * This searches for a device with the given seq.
608 *
609 * @parent: Parent device
610 * @seq: Sequence number to find (0=first)
611 * @devp: Returns pointer to device (there is only one per for each seq).
612 * Set to NULL if none is found
613 * @return 0 if OK, -ENODEV if not found
614 */
615 int device_find_child_by_seq(const struct udevice *parent, int seq,
616 struct udevice **devp);
617
618 /**
619 * device_get_child_by_seq() - Get a child device based on a sequence
620 *
621 * If an active device has this sequence it will be returned. If there is no
622 * such device then this will check for a device that is requesting this
623 * sequence.
624 *
625 * The device is probed to activate it ready for use.
626 *
627 * @parent: Parent device
628 * @seq: Sequence number to find (0=first)
629 * @devp: Returns pointer to device (there is only one per for each seq)
630 * Set to NULL if none is found
631 * @return 0 if OK, -ve on error
632 */
633 int device_get_child_by_seq(const struct udevice *parent, int seq,
634 struct udevice **devp);
635
636 /**
637 * device_find_child_by_of_offset() - Find a child device based on FDT offset
638 *
639 * Locates a child device by its device tree offset.
640 *
641 * @parent: Parent device
642 * @of_offset: Device tree offset to find
643 * @devp: Returns pointer to device if found, otherwise this is set to NULL
644 * @return 0 if OK, -ve on error
645 */
646 int device_find_child_by_of_offset(const struct udevice *parent, int of_offset,
647 struct udevice **devp);
648
649 /**
650 * device_get_child_by_of_offset() - Get a child device based on FDT offset
651 *
652 * Locates a child device by its device tree offset.
653 *
654 * The device is probed to activate it ready for use.
655 *
656 * @parent: Parent device
657 * @of_offset: Device tree offset to find
658 * @devp: Returns pointer to device if found, otherwise this is set to NULL
659 * @return 0 if OK, -ve on error
660 */
661 int device_get_child_by_of_offset(const struct udevice *parent, int of_offset,
662 struct udevice **devp);
663
664 /**
665 * device_find_global_by_ofnode() - Get a device based on ofnode
666 *
667 * Locates a device by its device tree ofnode, searching globally throughout
668 * the all driver model devices.
669 *
670 * The device is NOT probed
671 *
672 * @node: Device tree ofnode to find
673 * @devp: Returns pointer to device if found, otherwise this is set to NULL
674 * @return 0 if OK, -ve on error
675 */
676
677 int device_find_global_by_ofnode(ofnode node, struct udevice **devp);
678
679 /**
680 * device_get_global_by_ofnode() - Get a device based on ofnode
681 *
682 * Locates a device by its device tree ofnode, searching globally throughout
683 * the all driver model devices.
684 *
685 * The device is probed to activate it ready for use.
686 *
687 * @node: Device tree ofnode to find
688 * @devp: Returns pointer to device if found, otherwise this is set to NULL
689 * @return 0 if OK, -ve on error
690 */
691 int device_get_global_by_ofnode(ofnode node, struct udevice **devp);
692
693 /**
694 * device_get_by_ofplat_idx() - Get a device based on of-platdata index
695 *
696 * Locates a device by either its struct driver_info index, or its
697 * struct udevice index. The latter is used with OF_PLATDATA_INST, since we have
698 * a list of build-time instantiated struct udevice records, The former is used
699 * with !OF_PLATDATA_INST since in that case we have a list of
700 * struct driver_info records.
701 *
702 * The index number is written into the idx field of struct phandle_1_arg, etc.
703 * It is the position of this driver_info/udevice in its linker list.
704 *
705 * The device is probed to activate it ready for use.
706 *
707 * @idx: Index number of the driver_info/udevice structure (0=first)
708 * @devp: Returns pointer to device if found, otherwise this is set to NULL
709 * @return 0 if OK, -ve on error
710 */
711 int device_get_by_ofplat_idx(uint idx, struct udevice **devp);
712
713 /**
714 * device_find_first_child() - Find the first child of a device
715 *
716 * @parent: Parent device to search
717 * @devp: Returns first child device, or NULL if none
718 * @return 0
719 */
720 int device_find_first_child(const struct udevice *parent,
721 struct udevice **devp);
722
723 /**
724 * device_find_next_child() - Find the next child of a device
725 *
726 * @devp: Pointer to previous child device on entry. Returns pointer to next
727 * child device, or NULL if none
728 * @return 0
729 */
730 int device_find_next_child(struct udevice **devp);
731
732 /**
733 * device_find_first_inactive_child() - Find the first inactive child
734 *
735 * This is used to locate an existing child of a device which is of a given
736 * uclass.
737 *
738 * The device is NOT probed
739 *
740 * @parent: Parent device to search
741 * @uclass_id: Uclass to look for
742 * @devp: Returns device found, if any, else NULL
743 * @return 0 if found, else -ENODEV
744 */
745 int device_find_first_inactive_child(const struct udevice *parent,
746 enum uclass_id uclass_id,
747 struct udevice **devp);
748
749 /**
750 * device_find_first_child_by_uclass() - Find the first child of a device in uc
751 *
752 * @parent: Parent device to search
753 * @uclass_id: Uclass to look for
754 * @devp: Returns first child device in that uclass, if any, else NULL
755 * @return 0 if found, else -ENODEV
756 */
757 int device_find_first_child_by_uclass(const struct udevice *parent,
758 enum uclass_id uclass_id,
759 struct udevice **devp);
760
761 /**
762 * device_find_child_by_name() - Find a child by device name
763 *
764 * @parent: Parent device to search
765 * @name: Name to look for
766 * @devp: Returns device found, if any
767 * @return 0 if found, else -ENODEV
768 */
769 int device_find_child_by_name(const struct udevice *parent, const char *name,
770 struct udevice **devp);
771
772 /**
773 * device_first_child_ofdata_err() - Find the first child and reads its plat
774 *
775 * The of_to_plat() method is called on the child before it is returned,
776 * but the child is not probed.
777 *
778 * @parent: Parent to check
779 * @devp: Returns child that was found, if any
780 * @return 0 on success, -ENODEV if no children, other -ve on error
781 */
782 int device_first_child_ofdata_err(struct udevice *parent,
783 struct udevice **devp);
784
785 /*
786 * device_next_child_ofdata_err() - Find the next child and read its plat
787 *
788 * The of_to_plat() method is called on the child before it is returned,
789 * but the child is not probed.
790 *
791 * @devp: On entry, points to the previous child; on exit returns the child that
792 * was found, if any
793 * @return 0 on success, -ENODEV if no children, other -ve on error
794 */
795 int device_next_child_ofdata_err(struct udevice **devp);
796
797 /**
798 * device_first_child_err() - Get the first child of a device
799 *
800 * The device returned is probed if necessary, and ready for use
801 *
802 * @parent: Parent device to search
803 * @devp: Returns device found, if any
804 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
805 */
806 int device_first_child_err(struct udevice *parent, struct udevice **devp);
807
808 /**
809 * device_next_child_err() - Get the next child of a parent device
810 *
811 * The device returned is probed if necessary, and ready for use
812 *
813 * @devp: On entry, pointer to device to lookup. On exit, returns pointer
814 * to the next sibling if no error occurred
815 * @return 0 if found, -ENODEV if not, -ve error if device failed to probe
816 */
817 int device_next_child_err(struct udevice **devp);
818
819 /**
820 * device_has_children() - check if a device has any children
821 *
822 * @dev: Device to check
823 * @return true if the device has one or more children
824 */
825 bool device_has_children(const struct udevice *dev);
826
827 /**
828 * device_has_active_children() - check if a device has any active children
829 *
830 * @dev: Device to check
831 * @return true if the device has one or more children and at least one of
832 * them is active (probed).
833 */
834 bool device_has_active_children(const struct udevice *dev);
835
836 /**
837 * device_is_last_sibling() - check if a device is the last sibling
838 *
839 * This function can be useful for display purposes, when special action needs
840 * to be taken when displaying the last sibling. This can happen when a tree
841 * view of devices is being displayed.
842 *
843 * @dev: Device to check
844 * @return true if there are no more siblings after this one - i.e. is it
845 * last in the list.
846 */
847 bool device_is_last_sibling(const struct udevice *dev);
848
849 /**
850 * device_set_name() - set the name of a device
851 *
852 * This must be called in the device's bind() method and no later. Normally
853 * this is unnecessary but for probed devices which don't get a useful name
854 * this function can be helpful.
855 *
856 * The name is allocated and will be freed automatically when the device is
857 * unbound.
858 *
859 * @dev: Device to update
860 * @name: New name (this string is allocated new memory and attached to
861 * the device)
862 * @return 0 if OK, -ENOMEM if there is not enough memory to allocate the
863 * string
864 */
865 int device_set_name(struct udevice *dev, const char *name);
866
867 /**
868 * device_set_name_alloced() - note that a device name is allocated
869 *
870 * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
871 * unbound the name will be freed. This avoids memory leaks.
872 *
873 * @dev: Device to update
874 */
875 void device_set_name_alloced(struct udevice *dev);
876
877 /**
878 * device_is_compatible() - check if the device is compatible with the compat
879 *
880 * This allows to check whether the device is comaptible with the compat.
881 *
882 * @dev: udevice pointer for which compatible needs to be verified.
883 * @compat: Compatible string which needs to verified in the given
884 * device
885 * @return true if OK, false if the compatible is not found
886 */
887 bool device_is_compatible(const struct udevice *dev, const char *compat);
888
889 /**
890 * of_machine_is_compatible() - check if the machine is compatible with
891 * the compat
892 *
893 * This allows to check whether the machine is comaptible with the compat.
894 *
895 * @compat: Compatible string which needs to verified
896 * @return true if OK, false if the compatible is not found
897 */
898 bool of_machine_is_compatible(const char *compat);
899
900 /**
901 * dev_disable_by_path() - Disable a device given its device tree path
902 *
903 * @path: The device tree path identifying the device to be disabled
904 * @return 0 on success, -ve on error
905 */
906 int dev_disable_by_path(const char *path);
907
908 /**
909 * dev_enable_by_path() - Enable a device given its device tree path
910 *
911 * @path: The device tree path identifying the device to be enabled
912 * @return 0 on success, -ve on error
913 */
914 int dev_enable_by_path(const char *path);
915
916 /**
917 * device_is_on_pci_bus - Test if a device is on a PCI bus
918 *
919 * @dev: device to test
920 * @return: true if it is on a PCI bus, false otherwise
921 */
device_is_on_pci_bus(const struct udevice * dev)922 static inline bool device_is_on_pci_bus(const struct udevice *dev)
923 {
924 return dev->parent && device_get_uclass_id(dev->parent) == UCLASS_PCI;
925 }
926
927 /**
928 * device_foreach_child_safe() - iterate through child devices safely
929 *
930 * This allows the @pos child to be removed in the loop if required.
931 *
932 * @pos: struct udevice * for the current device
933 * @next: struct udevice * for the next device
934 * @parent: parent device to scan
935 */
936 #define device_foreach_child_safe(pos, next, parent) \
937 list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
938
939 /**
940 * device_foreach_child() - iterate through child devices
941 *
942 * @pos: struct udevice * for the current device
943 * @parent: parent device to scan
944 */
945 #define device_foreach_child(pos, parent) \
946 list_for_each_entry(pos, &parent->child_head, sibling_node)
947
948 /**
949 * device_foreach_child_of_to_plat() - iterate through children
950 *
951 * This stops when it gets an error, with @pos set to the device that failed to
952 * read ofdata.
953
954 * This creates a for() loop which works through the available children of
955 * a device in order from start to end. Device ofdata is read by calling
956 * device_of_to_plat() on each one. The devices are not probed.
957 *
958 * @pos: struct udevice * for the current device
959 * @parent: parent device to scan
960 */
961 #define device_foreach_child_of_to_plat(pos, parent) \
962 for (int _ret = device_first_child_ofdata_err(parent, &dev); !_ret; \
963 _ret = device_next_child_ofdata_err(&dev))
964
965 /**
966 * device_foreach_child_probe() - iterate through children, probing them
967 *
968 * This creates a for() loop which works through the available children of
969 * a device in order from start to end. Devices are probed if necessary,
970 * and ready for use.
971 *
972 * This stops when it gets an error, with @pos set to the device that failed to
973 * probe
974 *
975 * @pos: struct udevice * for the current device
976 * @parent: parent device to scan
977 */
978 #define device_foreach_child_probe(pos, parent) \
979 for (int _ret = device_first_child_err(parent, &dev); !_ret; \
980 _ret = device_next_child_err(&dev))
981
982 /**
983 * dm_scan_fdt_dev() - Bind child device in the device tree
984 *
985 * This handles device which have sub-nodes in the device tree. It scans all
986 * sub-nodes and binds drivers for each node where a driver can be found.
987 *
988 * If this is called prior to relocation, only pre-relocation devices will be
989 * bound (those marked with u-boot,dm-pre-reloc in the device tree, or where
990 * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
991 * be bound.
992 *
993 * @dev: Device to scan
994 * @return 0 if OK, -ve on error
995 */
996 int dm_scan_fdt_dev(struct udevice *dev);
997
998 #endif
999