include/dm/device.h

   1 /*
   2  * Copyright (c) 2013 Google, Inc
   3  *
   4  * (C) Copyright 2012
   5  * Pavel Herrmann <morpheus.ibis@gmail.com>
   6  * Marek Vasut <marex@denx.de>
   7  *
   8  * SPDX-License-Identifier:     GPL-2.0+
   9  */
  10
  11 #ifndef _DM_DEVICE_H
  12 #define _DM_DEVICE_H
  13
  14 #include <dm/uclass-id.h>
  15 #include <fdtdec.h>
  16 #include <linker_lists.h>
  17 #include <linux/compat.h>
  18 #include <linux/kernel.h>
  19 #include <linux/list.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 platdata */
  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_platdata */
  33 #define DM_FLAG_ALLOC_PARENT_PDATA      (1 << 3)
  34
  35 /* DM is responsible for allocating and freeing uclass_platdata */
  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 #define DM_FLAG_OF_PLATDATA             (1 << 8)
  48
  49 /*
  50  * Call driver remove function to stop currently active DMA transfers or
  51  * give DMA buffers back to the HW / controller. This may be needed for
  52  * some drivers to do some final stage cleanup before the OS is called
  53  * (U-Boot exit)
  54  */
  55 #define DM_FLAG_ACTIVE_DMA              (1 << 9)
  56
  57 /*
  58  * Call driver remove function to do some final configuration, before
  59  * U-Boot exits and the OS is started
  60  */
  61 #define DM_FLAG_OS_PREPARE              (1 << 10)
  62
  63 /*
  64  * One or multiple of these flags are passed to device_remove() so that
  65  * a selective device removal as specified by the remove-stage and the
  66  * driver flags can be done.
  67  */
  68 enum {
  69         /* Normal remove, remove all devices */
  70         DM_REMOVE_NORMAL     = 1 << 0,
  71
  72         /* Remove devices with active DMA */
  73         DM_REMOVE_ACTIVE_DMA = DM_FLAG_ACTIVE_DMA,
  74
  75         /* Remove devices which need some final OS preparation steps */
  76         DM_REMOVE_OS_PREPARE = DM_FLAG_OS_PREPARE,
  77
  78         /* Add more use cases here */
  79
  80         /* Remove devices with any active flag */
  81         DM_REMOVE_ACTIVE_ALL = DM_REMOVE_ACTIVE_DMA | DM_REMOVE_OS_PREPARE,
  82 };
  83
  84 /**
  85  * struct udevice - An instance of a driver
  86  *
  87  * This holds information about a device, which is a driver bound to a
  88  * particular port or peripheral (essentially a driver instance).
  89  *
  90  * A device will come into existence through a 'bind' call, either due to
  91  * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node
  92  * in the device tree (in which case of_offset is >= 0). In the latter case
  93  * we translate the device tree information into platdata in a function
  94  * implemented by the driver ofdata_to_platdata method (called just before the
  95  * probe method if the device has a device tree node.
  96  *
  97  * All three of platdata, priv and uclass_priv can be allocated by the
  98  * driver, or you can use the auto_alloc_size members of struct driver and
  99  * struct uclass_driver to have driver model do this automatically.
 100  *
 101  * @driver: The driver used by this device
 102  * @name: Name of device, typically the FDT node name
 103  * @platdata: Configuration data for this device
 104  * @parent_platdata: The parent bus's configuration data for this device
 105  * @uclass_platdata: The uclass's configuration data for this device
 106  * @of_offset: Device tree node offset for this device (- for none)
 107  * @driver_data: Driver data word for the entry that matched this device with
 108  *              its driver
 109  * @parent: Parent of this device, or NULL for the top level device
 110  * @priv: Private data for this device
 111  * @uclass: Pointer to uclass for this device
 112  * @uclass_priv: The uclass's private data for this device
 113  * @parent_priv: The parent's private data for this device
 114  * @uclass_node: Used by uclass to link its devices
 115  * @child_head: List of children of this device
 116  * @sibling_node: Next device in list of all devices
 117  * @flags: Flags for this device DM_FLAG_...
 118  * @req_seq: Requested sequence number for this device (-1 = any)
 119  * @seq: Allocated sequence number for this device (-1 = none). This is set up
 120  * when the device is probed and will be unique within the device's uclass.
 121  * @devres_head: List of memory allocations associated with this device.
 122  *              When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
 123  *              add to this list. Memory so-allocated will be freed
 124  *              automatically when the device is removed / unbound
 125  */
 126 struct udevice {
 127         const struct driver *driver;
 128         const char *name;
 129         void *platdata;
 130         void *parent_platdata;
 131         void *uclass_platdata;
 132         int of_offset;
 133         ulong driver_data;
 134         struct udevice *parent;
 135         void *priv;
 136         struct uclass *uclass;
 137         void *uclass_priv;
 138         void *parent_priv;
 139         struct list_head uclass_node;
 140         struct list_head child_head;
 141         struct list_head sibling_node;
 142         uint32_t flags;
 143         int req_seq;
 144         int seq;
 145 #ifdef CONFIG_DEVRES
 146         struct list_head devres_head;
 147 #endif
 148 };
 149
 150 /* Maximum sequence number supported */
 151 #define DM_MAX_SEQ      999
 152
 153 /* Returns the operations for a device */
 154 #define device_get_ops(dev)     (dev->driver->ops)
 155
 156 /* Returns non-zero if the device is active (probed and not removed) */
 157 #define device_active(dev)      ((dev)->flags & DM_FLAG_ACTIVATED)
 158
 159 static inline int dev_of_offset(const struct udevice *dev)
 160 {
 161         return dev->of_offset;
 162 }
 163
 164 static inline void dev_set_of_offset(struct udevice *dev, int of_offset)
 165 {
 166         dev->of_offset = of_offset;
 167 }
 168
 169 /**
 170  * struct udevice_id - Lists the compatible strings supported by a driver
 171  * @compatible: Compatible string
 172  * @data: Data for this compatible string
 173  */
 174 struct udevice_id {
 175         const char *compatible;
 176         ulong data;
 177 };
 178
 179 #if CONFIG_IS_ENABLED(OF_CONTROL)
 180 #define of_match_ptr(_ptr)      (_ptr)
 181 #else
 182 #define of_match_ptr(_ptr)      NULL
 183 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
 184
 185 /**
 186  * struct driver - A driver for a feature or peripheral
 187  *
 188  * This holds methods for setting up a new device, and also removing it.
 189  * The device needs information to set itself up - this is provided either
 190  * by platdata or a device tree node (which we find by looking up
 191  * matching compatible strings with of_match).
 192  *
 193  * Drivers all belong to a uclass, representing a class of devices of the
 194  * same type. Common elements of the drivers can be implemented in the uclass,
 195  * or the uclass can provide a consistent interface to the drivers within
 196  * it.
 197  *
 198  * @name: Device name
 199  * @id: Identiies the uclass we belong to
 200  * @of_match: List of compatible strings to match, and any identifying data
 201  * for each.
 202  * @bind: Called to bind a device to its driver
 203  * @probe: Called to probe a device, i.e. activate it
 204  * @remove: Called to remove a device, i.e. de-activate it
 205  * @unbind: Called to unbind a device from its driver
 206  * @ofdata_to_platdata: Called before probe to decode device tree data
 207  * @child_post_bind: Called after a new child has been bound
 208  * @child_pre_probe: Called before a child device is probed. The device has
 209  * memory allocated but it has not yet been probed.
 210  * @child_post_remove: Called after a child device is removed. The device
 211  * has memory allocated but its device_remove() method has been called.
 212  * @priv_auto_alloc_size: If non-zero this is the size of the private data
 213  * to be allocated in the device's ->priv pointer. If zero, then the driver
 214  * is responsible for allocating any data required.
 215  * @platdata_auto_alloc_size: If non-zero this is the size of the
 216  * platform data to be allocated in the device's ->platdata pointer.
 217  * This is typically only useful for device-tree-aware drivers (those with
 218  * an of_match), since drivers which use platdata will have the data
 219  * provided in the U_BOOT_DEVICE() instantiation.
 220  * @per_child_auto_alloc_size: Each device can hold private data owned by
 221  * its parent. If required this will be automatically allocated if this
 222  * value is non-zero.
 223  * @per_child_platdata_auto_alloc_size: A bus likes to store information about
 224  * its children. If non-zero this is the size of this data, to be allocated
 225  * in the child's parent_platdata pointer.
 226  * @ops: Driver-specific operations. This is typically a list of function
 227  * pointers defined by the driver, to implement driver functions required by
 228  * the uclass.
 229  * @flags: driver flags - see DM_FLAGS_...
 230  */
 231 struct driver {
 232         char *name;
 233         enum uclass_id id;
 234         const struct udevice_id *of_match;
 235         int (*bind)(struct udevice *dev);
 236         int (*probe)(struct udevice *dev);
 237         int (*remove)(struct udevice *dev);
 238         int (*unbind)(struct udevice *dev);
 239         int (*ofdata_to_platdata)(struct udevice *dev);
 240         int (*child_post_bind)(struct udevice *dev);
 241         int (*child_pre_probe)(struct udevice *dev);
 242         int (*child_post_remove)(struct udevice *dev);
 243         int priv_auto_alloc_size;
 244         int platdata_auto_alloc_size;
 245         int per_child_auto_alloc_size;
 246         int per_child_platdata_auto_alloc_size;
 247         const void *ops;        /* driver-specific operations */
 248         uint32_t flags;
 249 };
 250
 251 /* Declare a new U-Boot driver */
 252 #define U_BOOT_DRIVER(__name)                                           \
 253         ll_entry_declare(struct driver, __name, driver)
 254
 255 /* Get a pointer to a given driver */
 256 #define DM_GET_DRIVER(__name)                                           \
 257         ll_entry_get(struct driver, __name, driver)
 258
 259 /**
 260  * dev_get_platdata() - Get the platform data for a device
 261  *
 262  * This checks that dev is not NULL, but no other checks for now
 263  *
 264  * @dev         Device to check
 265  * @return platform data, or NULL if none
 266  */
 267 void *dev_get_platdata(struct udevice *dev);
 268
 269 /**
 270  * dev_get_parent_platdata() - Get the parent platform data for a device
 271  *
 272  * This checks that dev is not NULL, but no other checks for now
 273  *
 274  * @dev         Device to check
 275  * @return parent's platform data, or NULL if none
 276  */
 277 void *dev_get_parent_platdata(struct udevice *dev);
 278
 279 /**
 280  * dev_get_uclass_platdata() - Get the uclass platform data for a device
 281  *
 282  * This checks that dev is not NULL, but no other checks for now
 283  *
 284  * @dev         Device to check
 285  * @return uclass's platform data, or NULL if none
 286  */
 287 void *dev_get_uclass_platdata(struct udevice *dev);
 288
 289 /**
 290  * dev_get_priv() - Get the private data for a device
 291  *
 292  * This checks that dev is not NULL, but no other checks for now
 293  *
 294  * @dev         Device to check
 295  * @return private data, or NULL if none
 296  */
 297 void *dev_get_priv(struct udevice *dev);
 298
 299 /**
 300  * dev_get_parent_priv() - Get the parent private data for a device
 301  *
 302  * The parent private data is data stored in the device but owned by the
 303  * parent. For example, a USB device may have parent data which contains
 304  * information about how to talk to the device over USB.
 305  *
 306  * This checks that dev is not NULL, but no other checks for now
 307  *
 308  * @dev         Device to check
 309  * @return parent data, or NULL if none
 310  */
 311 void *dev_get_parent_priv(struct udevice *dev);
 312
 313 /**
 314  * dev_get_uclass_priv() - Get the private uclass data for a device
 315  *
 316  * This checks that dev is not NULL, but no other checks for now
 317  *
 318  * @dev         Device to check
 319  * @return private uclass data for this device, or NULL if none
 320  */
 321 void *dev_get_uclass_priv(struct udevice *dev);
 322
 323 /**
 324  * struct dev_get_parent() - Get the parent of a device
 325  *
 326  * @child:      Child to check
 327  * @return parent of child, or NULL if this is the root device
 328  */
 329 struct udevice *dev_get_parent(struct udevice *child);
 330
 331 /**
 332  * dev_get_driver_data() - get the driver data used to bind a device
 333  *
 334  * When a device is bound using a device tree node, it matches a
 335  * particular compatible string in struct udevice_id. This function
 336  * returns the associated data value for that compatible string. This is
 337  * the 'data' field in struct udevice_id.
 338  *
 339  * As an example, consider this structure:
 340  * static const struct udevice_id tegra_i2c_ids[] = {
 341  *      { .compatible = "nvidia,tegra114-i2c", .data = TYPE_114 },
 342  *      { .compatible = "nvidia,tegra20-i2c", .data = TYPE_STD },
 343  *      { .compatible = "nvidia,tegra20-i2c-dvc", .data = TYPE_DVC },
 344  *      { }
 345  * };
 346  *
 347  * When driver model finds a driver for this it will store the 'data' value
 348  * corresponding to the compatible string it matches. This function returns
 349  * that value. This allows the driver to handle several variants of a device.
 350  *
 351  * For USB devices, this is the driver_info field in struct usb_device_id.
 352  *
 353  * @dev:        Device to check
 354  * @return driver data (0 if none is provided)
 355  */
 356 ulong dev_get_driver_data(struct udevice *dev);
 357
 358 /**
 359  * dev_get_driver_ops() - get the device's driver's operations
 360  *
 361  * This checks that dev is not NULL, and returns the pointer to device's
 362  * driver's operations.
 363  *
 364  * @dev:        Device to check
 365  * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
 366  */
 367 const void *dev_get_driver_ops(struct udevice *dev);
 368
 369 /**
 370  * device_get_uclass_id() - return the uclass ID of a device
 371  *
 372  * @dev:        Device to check
 373  * @return uclass ID for the device
 374  */
 375 enum uclass_id device_get_uclass_id(struct udevice *dev);
 376
 377 /**
 378  * dev_get_uclass_name() - return the uclass name of a device
 379  *
 380  * This checks that dev is not NULL.
 381  *
 382  * @dev:        Device to check
 383  * @return  pointer to the uclass name for the device
 384  */
 385 const char *dev_get_uclass_name(struct udevice *dev);
 386
 387 /**
 388  * device_get_child() - Get the child of a device by index
 389  *
 390  * Returns the numbered child, 0 being the first. This does not use
 391  * sequence numbers, only the natural order.
 392  *
 393  * @dev:        Parent device to check
 394  * @index:      Child index
 395  * @devp:       Returns pointer to device
 396  * @return 0 if OK, -ENODEV if no such device, other error if the device fails
 397  *         to probe
 398  */
 399 int device_get_child(struct udevice *parent, int index, struct udevice **devp);
 400
 401 /**
 402  * device_find_child_by_seq() - Find a child device based on a sequence
 403  *
 404  * This searches for a device with the given seq or req_seq.
 405  *
 406  * For seq, if an active device has this sequence it will be returned.
 407  * If there is no such device then this will return -ENODEV.
 408  *
 409  * For req_seq, if a device (whether activated or not) has this req_seq
 410  * value, that device will be returned. This is a strong indication that
 411  * the device will receive that sequence when activated.
 412  *
 413  * @parent: Parent device
 414  * @seq_or_req_seq: Sequence number to find (0=first)
 415  * @find_req_seq: true to find req_seq, false to find seq
 416  * @devp: Returns pointer to device (there is only one per for each seq).
 417  * Set to NULL if none is found
 418  * @return 0 if OK, -ve on error
 419  */
 420 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq,
 421                              bool find_req_seq, struct udevice **devp);
 422
 423 /**
 424  * device_get_child_by_seq() - Get a child device based on a sequence
 425  *
 426  * If an active device has this sequence it will be returned. If there is no
 427  * such device then this will check for a device that is requesting this
 428  * sequence.
 429  *
 430  * The device is probed to activate it ready for use.
 431  *
 432  * @parent: Parent device
 433  * @seq: Sequence number to find (0=first)
 434  * @devp: Returns pointer to device (there is only one per for each seq)
 435  * Set to NULL if none is found
 436  * @return 0 if OK, -ve on error
 437  */
 438 int device_get_child_by_seq(struct udevice *parent, int seq,
 439                             struct udevice **devp);
 440
 441 /**
 442  * device_find_child_by_of_offset() - Find a child device based on FDT offset
 443  *
 444  * Locates a child device by its device tree offset.
 445  *
 446  * @parent: Parent device
 447  * @of_offset: Device tree offset to find
 448  * @devp: Returns pointer to device if found, otherwise this is set to NULL
 449  * @return 0 if OK, -ve on error
 450  */
 451 int device_find_child_by_of_offset(struct udevice *parent, int of_offset,
 452                                    struct udevice **devp);
 453
 454 /**
 455  * device_get_child_by_of_offset() - Get a child device based on FDT offset
 456  *
 457  * Locates a child device by its device tree offset.
 458  *
 459  * The device is probed to activate it ready for use.
 460  *
 461  * @parent: Parent device
 462  * @of_offset: Device tree offset to find
 463  * @devp: Returns pointer to device if found, otherwise this is set to NULL
 464  * @return 0 if OK, -ve on error
 465  */
 466 int device_get_child_by_of_offset(struct udevice *parent, int of_offset,
 467                                   struct udevice **devp);
 468
 469 /**
 470  * device_get_global_by_of_offset() - Get a device based on FDT offset
 471  *
 472  * Locates a device by its device tree offset, searching globally throughout
 473  * the all driver model devices.
 474  *
 475  * The device is probed to activate it ready for use.
 476  *
 477  * @of_offset: Device tree offset to find
 478  * @devp: Returns pointer to device if found, otherwise this is set to NULL
 479  * @return 0 if OK, -ve on error
 480  */
 481 int device_get_global_by_of_offset(int of_offset, struct udevice **devp);
 482
 483 /**
 484  * device_find_first_child() - Find the first child of a device
 485  *
 486  * @parent: Parent device to search
 487  * @devp: Returns first child device, or NULL if none
 488  * @return 0
 489  */
 490 int device_find_first_child(struct udevice *parent, struct udevice **devp);
 491
 492 /**
 493  * device_find_next_child() - Find the next child of a device
 494  *
 495  * @devp: Pointer to previous child device on entry. Returns pointer to next
 496  *              child device, or NULL if none
 497  * @return 0
 498  */
 499 int device_find_next_child(struct udevice **devp);
 500
 501 /**
 502  * device_has_children() - check if a device has any children
 503  *
 504  * @dev:        Device to check
 505  * @return true if the device has one or more children
 506  */
 507 bool device_has_children(struct udevice *dev);
 508
 509 /**
 510  * device_has_active_children() - check if a device has any active children
 511  *
 512  * @dev:        Device to check
 513  * @return true if the device has one or more children and at least one of
 514  * them is active (probed).
 515  */
 516 bool device_has_active_children(struct udevice *dev);
 517
 518 /**
 519  * device_is_last_sibling() - check if a device is the last sibling
 520  *
 521  * This function can be useful for display purposes, when special action needs
 522  * to be taken when displaying the last sibling. This can happen when a tree
 523  * view of devices is being displayed.
 524  *
 525  * @dev:        Device to check
 526  * @return true if there are no more siblings after this one - i.e. is it
 527  * last in the list.
 528  */
 529 bool device_is_last_sibling(struct udevice *dev);
 530
 531 /**
 532  * device_set_name() - set the name of a device
 533  *
 534  * This must be called in the device's bind() method and no later. Normally
 535  * this is unnecessary but for probed devices which don't get a useful name
 536  * this function can be helpful.
 537  *
 538  * The name is allocated and will be freed automatically when the device is
 539  * unbound.
 540  *
 541  * @dev:        Device to update
 542  * @name:       New name (this string is allocated new memory and attached to
 543  *              the device)
 544  * @return 0 if OK, -ENOMEM if there is not enough memory to allocate the
 545  * string
 546  */
 547 int device_set_name(struct udevice *dev, const char *name);
 548
 549 /**
 550  * device_set_name_alloced() - note that a device name is allocated
 551  *
 552  * This sets the DM_FLAG_NAME_ALLOCED flag for the device, so that when it is
 553  * unbound the name will be freed. This avoids memory leaks.
 554  *
 555  * @dev:        Device to update
 556  */
 557 void device_set_name_alloced(struct udevice *dev);
 558
 559 /**
 560  * of_device_is_compatible() - check if the device is compatible with the compat
 561  *
 562  * This allows to check whether the device is comaptible with the compat.
 563  *
 564  * @dev:        udevice pointer for which compatible needs to be verified.
 565  * @compat:     Compatible string which needs to verified in the given
 566  *              device
 567  * @return true if OK, false if the compatible is not found
 568  */
 569 bool of_device_is_compatible(struct udevice *dev, const char *compat);
 570
 571 /**
 572  * of_machine_is_compatible() - check if the machine is compatible with
 573  *                              the compat
 574  *
 575  * This allows to check whether the machine is comaptible with the compat.
 576  *
 577  * @compat:     Compatible string which needs to verified
 578  * @return true if OK, false if the compatible is not found
 579  */
 580 bool of_machine_is_compatible(const char *compat);
 581
 582 /**
 583  * device_is_on_pci_bus - Test if a device is on a PCI bus
 584  *
 585  * @dev:        device to test
 586  * @return:     true if it is on a PCI bus, false otherwise
 587  */
 588 static inline bool device_is_on_pci_bus(struct udevice *dev)
 589 {
 590         return device_get_uclass_id(dev->parent) == UCLASS_PCI;
 591 }
 592
 593 /**
 594  * device_foreach_child_safe() - iterate through child devices safely
 595  *
 596  * This allows the @pos child to be removed in the loop if required.
 597  *
 598  * @pos: struct udevice * for the current device
 599  * @next: struct udevice * for the next device
 600  * @parent: parent device to scan
 601  */
 602 #define device_foreach_child_safe(pos, next, parent)    \
 603         list_for_each_entry_safe(pos, next, &parent->child_head, sibling_node)
 604
 605 /**
 606  * dm_scan_fdt_dev() - Bind child device in a the device tree
 607  *
 608  * This handles device which have sub-nodes in the device tree. It scans all
 609  * sub-nodes and binds drivers for each node where a driver can be found.
 610  *
 611  * If this is called prior to relocation, only pre-relocation devices will be
 612  * bound (those marked with u-boot,dm-pre-reloc in the device tree, or where
 613  * the driver has the DM_FLAG_PRE_RELOC flag set). Otherwise, all devices will
 614  * be bound.
 615  *
 616  * @dev:        Device to scan
 617  * @return 0 if OK, -ve on error
 618  */
 619 int dm_scan_fdt_dev(struct udevice *dev);
 620
 621 /* device resource management */
 622 typedef void (*dr_release_t)(struct udevice *dev, void *res);
 623 typedef int (*dr_match_t)(struct udevice *dev, void *res, void *match_data);
 624
 625 #ifdef CONFIG_DEVRES
 626
 627 #ifdef CONFIG_DEBUG_DEVRES
 628 void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
 629                      const char *name);
 630 #define _devres_alloc(release, size, gfp) \
 631         __devres_alloc(release, size, gfp, #release)
 632 #else
 633 void *_devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
 634 #endif
 635
 636 /**
 637  * devres_alloc() - Allocate device resource data
 638  * @release: Release function devres will be associated with
 639  * @size: Allocation size
 640  * @gfp: Allocation flags
 641  *
 642  * Allocate devres of @size bytes.  The allocated area is associated
 643  * with @release.  The returned pointer can be passed to
 644  * other devres_*() functions.
 645  *
 646  * RETURNS:
 647  * Pointer to allocated devres on success, NULL on failure.
 648  */
 649 #define devres_alloc(release, size, gfp) \
 650         _devres_alloc(release, size, gfp | __GFP_ZERO)
 651
 652 /**
 653  * devres_free() - Free device resource data
 654  * @res: Pointer to devres data to free
 655  *
 656  * Free devres created with devres_alloc().
 657  */
 658 void devres_free(void *res);
 659
 660 /**
 661  * devres_add() - Register device resource
 662  * @dev: Device to add resource to
 663  * @res: Resource to register
 664  *
 665  * Register devres @res to @dev.  @res should have been allocated
 666  * using devres_alloc().  On driver detach, the associated release
 667  * function will be invoked and devres will be freed automatically.
 668  */
 669 void devres_add(struct udevice *dev, void *res);
 670
 671 /**
 672  * devres_find() - Find device resource
 673  * @dev: Device to lookup resource from
 674  * @release: Look for resources associated with this release function
 675  * @match: Match function (optional)
 676  * @match_data: Data for the match function
 677  *
 678  * Find the latest devres of @dev which is associated with @release
 679  * and for which @match returns 1.  If @match is NULL, it's considered
 680  * to match all.
 681  *
 682  * @return pointer to found devres, NULL if not found.
 683  */
 684 void *devres_find(struct udevice *dev, dr_release_t release,
 685                   dr_match_t match, void *match_data);
 686
 687 /**
 688  * devres_get() - Find devres, if non-existent, add one atomically
 689  * @dev: Device to lookup or add devres for
 690  * @new_res: Pointer to new initialized devres to add if not found
 691  * @match: Match function (optional)
 692  * @match_data: Data for the match function
 693  *
 694  * Find the latest devres of @dev which has the same release function
 695  * as @new_res and for which @match return 1.  If found, @new_res is
 696  * freed; otherwise, @new_res is added atomically.
 697  *
 698  * @return ointer to found or added devres.
 699  */
 700 void *devres_get(struct udevice *dev, void *new_res,
 701                  dr_match_t match, void *match_data);
 702
 703 /**
 704  * devres_remove() - Find a device resource and remove it
 705  * @dev: Device to find resource from
 706  * @release: Look for resources associated with this release function
 707  * @match: Match function (optional)
 708  * @match_data: Data for the match function
 709  *
 710  * Find the latest devres of @dev associated with @release and for
 711  * which @match returns 1.  If @match is NULL, it's considered to
 712  * match all.  If found, the resource is removed atomically and
 713  * returned.
 714  *
 715  * @return ointer to removed devres on success, NULL if not found.
 716  */
 717 void *devres_remove(struct udevice *dev, dr_release_t release,
 718                     dr_match_t match, void *match_data);
 719
 720 /**
 721  * devres_destroy() - Find a device resource and destroy it
 722  * @dev: Device to find resource from
 723  * @release: Look for resources associated with this release function
 724  * @match: Match function (optional)
 725  * @match_data: Data for the match function
 726  *
 727  * Find the latest devres of @dev associated with @release and for
 728  * which @match returns 1.  If @match is NULL, it's considered to
 729  * match all.  If found, the resource is removed atomically and freed.
 730  *
 731  * Note that the release function for the resource will not be called,
 732  * only the devres-allocated data will be freed.  The caller becomes
 733  * responsible for freeing any other data.
 734  *
 735  * @return 0 if devres is found and freed, -ENOENT if not found.
 736  */
 737 int devres_destroy(struct udevice *dev, dr_release_t release,
 738                    dr_match_t match, void *match_data);
 739
 740 /**
 741  * devres_release() - Find a device resource and destroy it, calling release
 742  * @dev: Device to find resource from
 743  * @release: Look for resources associated with this release function
 744  * @match: Match function (optional)
 745  * @match_data: Data for the match function
 746  *
 747  * Find the latest devres of @dev associated with @release and for
 748  * which @match returns 1.  If @match is NULL, it's considered to
 749  * match all.  If found, the resource is removed atomically, the
 750  * release function called and the resource freed.
 751  *
 752  * @return 0 if devres is found and freed, -ENOENT if not found.
 753  */
 754 int devres_release(struct udevice *dev, dr_release_t release,
 755                    dr_match_t match, void *match_data);
 756
 757 /* managed devm_k.alloc/kfree for device drivers */
 758 /**
 759  * devm_kmalloc() - Resource-managed kmalloc
 760  * @dev: Device to allocate memory for
 761  * @size: Allocation size
 762  * @gfp: Allocation gfp flags
 763  *
 764  * Managed kmalloc.  Memory allocated with this function is
 765  * automatically freed on driver detach.  Like all other devres
 766  * resources, guaranteed alignment is unsigned long long.
 767  *
 768  * @return pointer to allocated memory on success, NULL on failure.
 769  */
 770 void *devm_kmalloc(struct udevice *dev, size_t size, gfp_t gfp);
 771 static inline void *devm_kzalloc(struct udevice *dev, size_t size, gfp_t gfp)
 772 {
 773         return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
 774 }
 775 static inline void *devm_kmalloc_array(struct udevice *dev,
 776                                        size_t n, size_t size, gfp_t flags)
 777 {
 778         if (size != 0 && n > SIZE_MAX / size)
 779                 return NULL;
 780         return devm_kmalloc(dev, n * size, flags);
 781 }
 782 static inline void *devm_kcalloc(struct udevice *dev,
 783                                  size_t n, size_t size, gfp_t flags)
 784 {
 785         return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 786 }
 787
 788 /**
 789  * devm_kfree() - Resource-managed kfree
 790  * @dev: Device this memory belongs to
 791  * @ptr: Memory to free
 792  *
 793  * Free memory allocated with devm_kmalloc().
 794  */
 795 void devm_kfree(struct udevice *dev, void *ptr);
 796
 797 #else /* ! CONFIG_DEVRES */
 798
 799 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
 800 {
 801         return kzalloc(size, gfp);
 802 }
 803
 804 static inline void devres_free(void *res)
 805 {
 806         kfree(res);
 807 }
 808
 809 static inline void devres_add(struct udevice *dev, void *res)
 810 {
 811 }
 812
 813 static inline void *devres_find(struct udevice *dev, dr_release_t release,
 814                                 dr_match_t match, void *match_data)
 815 {
 816         return NULL;
 817 }
 818
 819 static inline void *devres_get(struct udevice *dev, void *new_res,
 820                                dr_match_t match, void *match_data)
 821 {
 822         return NULL;
 823 }
 824
 825 static inline void *devres_remove(struct udevice *dev, dr_release_t release,
 826                                   dr_match_t match, void *match_data)
 827 {
 828         return NULL;
 829 }
 830
 831 static inline int devres_destroy(struct udevice *dev, dr_release_t release,
 832                                  dr_match_t match, void *match_data)
 833 {
 834         return 0;
 835 }
 836
 837 static inline int devres_release(struct udevice *dev, dr_release_t release,
 838                                  dr_match_t match, void *match_data)
 839 {
 840         return 0;
 841 }
 842
 843 static inline void *devm_kmalloc(struct udevice *dev, size_t size, gfp_t gfp)
 844 {
 845         return kmalloc(size, gfp);
 846 }
 847
 848 static inline void *devm_kzalloc(struct udevice *dev, size_t size, gfp_t gfp)
 849 {
 850         return kzalloc(size, gfp);
 851 }
 852
 853 static inline void *devm_kmaloc_array(struct udevice *dev,
 854                                       size_t n, size_t size, gfp_t flags)
 855 {
 856         /* TODO: add kmalloc_array() to linux/compat.h */
 857         if (size != 0 && n > SIZE_MAX / size)
 858                 return NULL;
 859         return kmalloc(n * size, flags);
 860 }
 861
 862 static inline void *devm_kcalloc(struct udevice *dev,
 863                                  size_t n, size_t size, gfp_t flags)
 864 {
 865         /* TODO: add kcalloc() to linux/compat.h */
 866         return kmalloc(n * size, flags | __GFP_ZERO);
 867 }
 868
 869 static inline void devm_kfree(struct udevice *dev, void *ptr)
 870 {
 871         kfree(ptr);
 872 }
 873
 874 #endif /* ! CONFIG_DEVRES */
 875
 876 #endif