thunderbolt.h (21379B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * Thunderbolt service API 4 * 5 * Copyright (C) 2014 Andreas Noever <andreas.noever@gmail.com> 6 * Copyright (C) 2017, Intel Corporation 7 * Authors: Michael Jamet <michael.jamet@intel.com> 8 * Mika Westerberg <mika.westerberg@linux.intel.com> 9 */ 10 11#ifndef THUNDERBOLT_H_ 12#define THUNDERBOLT_H_ 13 14#include <linux/device.h> 15#include <linux/idr.h> 16#include <linux/list.h> 17#include <linux/mutex.h> 18#include <linux/mod_devicetable.h> 19#include <linux/pci.h> 20#include <linux/uuid.h> 21#include <linux/workqueue.h> 22 23enum tb_cfg_pkg_type { 24 TB_CFG_PKG_READ = 1, 25 TB_CFG_PKG_WRITE = 2, 26 TB_CFG_PKG_ERROR = 3, 27 TB_CFG_PKG_NOTIFY_ACK = 4, 28 TB_CFG_PKG_EVENT = 5, 29 TB_CFG_PKG_XDOMAIN_REQ = 6, 30 TB_CFG_PKG_XDOMAIN_RESP = 7, 31 TB_CFG_PKG_OVERRIDE = 8, 32 TB_CFG_PKG_RESET = 9, 33 TB_CFG_PKG_ICM_EVENT = 10, 34 TB_CFG_PKG_ICM_CMD = 11, 35 TB_CFG_PKG_ICM_RESP = 12, 36 TB_CFG_PKG_PREPARE_TO_SLEEP = 13, 37}; 38 39/** 40 * enum tb_security_level - Thunderbolt security level 41 * @TB_SECURITY_NONE: No security, legacy mode 42 * @TB_SECURITY_USER: User approval required at minimum 43 * @TB_SECURITY_SECURE: One time saved key required at minimum 44 * @TB_SECURITY_DPONLY: Only tunnel Display port (and USB) 45 * @TB_SECURITY_USBONLY: Only tunnel USB controller of the connected 46 * Thunderbolt dock (and Display Port). All PCIe 47 * links downstream of the dock are removed. 48 * @TB_SECURITY_NOPCIE: For USB4 systems this level is used when the 49 * PCIe tunneling is disabled from the BIOS. 50 */ 51enum tb_security_level { 52 TB_SECURITY_NONE, 53 TB_SECURITY_USER, 54 TB_SECURITY_SECURE, 55 TB_SECURITY_DPONLY, 56 TB_SECURITY_USBONLY, 57 TB_SECURITY_NOPCIE, 58}; 59 60/** 61 * struct tb - main thunderbolt bus structure 62 * @dev: Domain device 63 * @lock: Big lock. Must be held when accessing any struct 64 * tb_switch / struct tb_port. 65 * @nhi: Pointer to the NHI structure 66 * @ctl: Control channel for this domain 67 * @wq: Ordered workqueue for all domain specific work 68 * @root_switch: Root switch of this domain 69 * @cm_ops: Connection manager specific operations vector 70 * @index: Linux assigned domain number 71 * @security_level: Current security level 72 * @nboot_acl: Number of boot ACLs the domain supports 73 * @privdata: Private connection manager specific data 74 */ 75struct tb { 76 struct device dev; 77 struct mutex lock; 78 struct tb_nhi *nhi; 79 struct tb_ctl *ctl; 80 struct workqueue_struct *wq; 81 struct tb_switch *root_switch; 82 const struct tb_cm_ops *cm_ops; 83 int index; 84 enum tb_security_level security_level; 85 size_t nboot_acl; 86 unsigned long privdata[]; 87}; 88 89extern struct bus_type tb_bus_type; 90extern struct device_type tb_service_type; 91extern struct device_type tb_xdomain_type; 92 93#define TB_LINKS_PER_PHY_PORT 2 94 95static inline unsigned int tb_phy_port_from_link(unsigned int link) 96{ 97 return (link - 1) / TB_LINKS_PER_PHY_PORT; 98} 99 100/** 101 * struct tb_property_dir - XDomain property directory 102 * @uuid: Directory UUID or %NULL if root directory 103 * @properties: List of properties in this directory 104 * 105 * User needs to provide serialization if needed. 106 */ 107struct tb_property_dir { 108 const uuid_t *uuid; 109 struct list_head properties; 110}; 111 112enum tb_property_type { 113 TB_PROPERTY_TYPE_UNKNOWN = 0x00, 114 TB_PROPERTY_TYPE_DIRECTORY = 0x44, 115 TB_PROPERTY_TYPE_DATA = 0x64, 116 TB_PROPERTY_TYPE_TEXT = 0x74, 117 TB_PROPERTY_TYPE_VALUE = 0x76, 118}; 119 120#define TB_PROPERTY_KEY_SIZE 8 121 122/** 123 * struct tb_property - XDomain property 124 * @list: Used to link properties together in a directory 125 * @key: Key for the property (always terminated). 126 * @type: Type of the property 127 * @length: Length of the property data in dwords 128 * @value: Property value 129 * 130 * Users use @type to determine which field in @value is filled. 131 */ 132struct tb_property { 133 struct list_head list; 134 char key[TB_PROPERTY_KEY_SIZE + 1]; 135 enum tb_property_type type; 136 size_t length; 137 union { 138 struct tb_property_dir *dir; 139 u8 *data; 140 char *text; 141 u32 immediate; 142 } value; 143}; 144 145struct tb_property_dir *tb_property_parse_dir(const u32 *block, 146 size_t block_len); 147ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block, 148 size_t block_len); 149struct tb_property_dir *tb_property_copy_dir(const struct tb_property_dir *dir); 150struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid); 151void tb_property_free_dir(struct tb_property_dir *dir); 152int tb_property_add_immediate(struct tb_property_dir *parent, const char *key, 153 u32 value); 154int tb_property_add_data(struct tb_property_dir *parent, const char *key, 155 const void *buf, size_t buflen); 156int tb_property_add_text(struct tb_property_dir *parent, const char *key, 157 const char *text); 158int tb_property_add_dir(struct tb_property_dir *parent, const char *key, 159 struct tb_property_dir *dir); 160void tb_property_remove(struct tb_property *tb_property); 161struct tb_property *tb_property_find(struct tb_property_dir *dir, 162 const char *key, enum tb_property_type type); 163struct tb_property *tb_property_get_next(struct tb_property_dir *dir, 164 struct tb_property *prev); 165 166#define tb_property_for_each(dir, property) \ 167 for (property = tb_property_get_next(dir, NULL); \ 168 property; \ 169 property = tb_property_get_next(dir, property)) 170 171int tb_register_property_dir(const char *key, struct tb_property_dir *dir); 172void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir); 173 174/** 175 * struct tb_xdomain - Cross-domain (XDomain) connection 176 * @dev: XDomain device 177 * @tb: Pointer to the domain 178 * @remote_uuid: UUID of the remote domain (host) 179 * @local_uuid: Cached local UUID 180 * @route: Route string the other domain can be reached 181 * @vendor: Vendor ID of the remote domain 182 * @device: Device ID of the demote domain 183 * @local_max_hopid: Maximum input HopID of this host 184 * @remote_max_hopid: Maximum input HopID of the remote host 185 * @lock: Lock to serialize access to the following fields of this structure 186 * @vendor_name: Name of the vendor (or %NULL if not known) 187 * @device_name: Name of the device (or %NULL if not known) 188 * @link_speed: Speed of the link in Gb/s 189 * @link_width: Width of the link (1 or 2) 190 * @is_unplugged: The XDomain is unplugged 191 * @needs_uuid: If the XDomain does not have @remote_uuid it will be 192 * queried first 193 * @service_ids: Used to generate IDs for the services 194 * @in_hopids: Input HopIDs for DMA tunneling 195 * @out_hopids; Output HopIDs for DMA tunneling 196 * @local_property_block: Local block of properties 197 * @local_property_block_gen: Generation of @local_property_block 198 * @local_property_block_len: Length of the @local_property_block in dwords 199 * @remote_properties: Properties exported by the remote domain 200 * @remote_property_block_gen: Generation of @remote_properties 201 * @state: Next XDomain discovery state to run 202 * @state_work: Work used to run the next state 203 * @state_retries: Number of retries remain for the state 204 * @properties_changed_work: Work used to notify the remote domain that 205 * our properties have changed 206 * @properties_changed_retries: Number of times left to send properties 207 * changed notification 208 * @bonding_possible: True if lane bonding is possible on local side 209 * @target_link_width: Target link width from the remote host 210 * @link: Root switch link the remote domain is connected (ICM only) 211 * @depth: Depth in the chain the remote domain is connected (ICM only) 212 * 213 * This structure represents connection across two domains (hosts). 214 * Each XDomain contains zero or more services which are exposed as 215 * &struct tb_service objects. 216 * 217 * Service drivers may access this structure if they need to enumerate 218 * non-standard properties but they need hold @lock when doing so 219 * because properties can be changed asynchronously in response to 220 * changes in the remote domain. 221 */ 222struct tb_xdomain { 223 struct device dev; 224 struct tb *tb; 225 uuid_t *remote_uuid; 226 const uuid_t *local_uuid; 227 u64 route; 228 u16 vendor; 229 u16 device; 230 unsigned int local_max_hopid; 231 unsigned int remote_max_hopid; 232 struct mutex lock; 233 const char *vendor_name; 234 const char *device_name; 235 unsigned int link_speed; 236 unsigned int link_width; 237 bool is_unplugged; 238 bool needs_uuid; 239 struct ida service_ids; 240 struct ida in_hopids; 241 struct ida out_hopids; 242 u32 *local_property_block; 243 u32 local_property_block_gen; 244 u32 local_property_block_len; 245 struct tb_property_dir *remote_properties; 246 u32 remote_property_block_gen; 247 int state; 248 struct delayed_work state_work; 249 int state_retries; 250 struct delayed_work properties_changed_work; 251 int properties_changed_retries; 252 bool bonding_possible; 253 u8 target_link_width; 254 u8 link; 255 u8 depth; 256}; 257 258int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd); 259void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd); 260int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid); 261void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid); 262int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid); 263void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid); 264int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path, 265 int transmit_ring, int receive_path, 266 int receive_ring); 267int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path, 268 int transmit_ring, int receive_path, 269 int receive_ring); 270 271static inline int tb_xdomain_disable_all_paths(struct tb_xdomain *xd) 272{ 273 return tb_xdomain_disable_paths(xd, -1, -1, -1, -1); 274} 275 276struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid); 277struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route); 278 279static inline struct tb_xdomain * 280tb_xdomain_find_by_uuid_locked(struct tb *tb, const uuid_t *uuid) 281{ 282 struct tb_xdomain *xd; 283 284 mutex_lock(&tb->lock); 285 xd = tb_xdomain_find_by_uuid(tb, uuid); 286 mutex_unlock(&tb->lock); 287 288 return xd; 289} 290 291static inline struct tb_xdomain * 292tb_xdomain_find_by_route_locked(struct tb *tb, u64 route) 293{ 294 struct tb_xdomain *xd; 295 296 mutex_lock(&tb->lock); 297 xd = tb_xdomain_find_by_route(tb, route); 298 mutex_unlock(&tb->lock); 299 300 return xd; 301} 302 303static inline struct tb_xdomain *tb_xdomain_get(struct tb_xdomain *xd) 304{ 305 if (xd) 306 get_device(&xd->dev); 307 return xd; 308} 309 310static inline void tb_xdomain_put(struct tb_xdomain *xd) 311{ 312 if (xd) 313 put_device(&xd->dev); 314} 315 316static inline bool tb_is_xdomain(const struct device *dev) 317{ 318 return dev->type == &tb_xdomain_type; 319} 320 321static inline struct tb_xdomain *tb_to_xdomain(struct device *dev) 322{ 323 if (tb_is_xdomain(dev)) 324 return container_of(dev, struct tb_xdomain, dev); 325 return NULL; 326} 327 328int tb_xdomain_response(struct tb_xdomain *xd, const void *response, 329 size_t size, enum tb_cfg_pkg_type type); 330int tb_xdomain_request(struct tb_xdomain *xd, const void *request, 331 size_t request_size, enum tb_cfg_pkg_type request_type, 332 void *response, size_t response_size, 333 enum tb_cfg_pkg_type response_type, 334 unsigned int timeout_msec); 335 336/** 337 * tb_protocol_handler - Protocol specific handler 338 * @uuid: XDomain messages with this UUID are dispatched to this handler 339 * @callback: Callback called with the XDomain message. Returning %1 340 * here tells the XDomain core that the message was handled 341 * by this handler and should not be forwared to other 342 * handlers. 343 * @data: Data passed with the callback 344 * @list: Handlers are linked using this 345 * 346 * Thunderbolt services can hook into incoming XDomain requests by 347 * registering protocol handler. Only limitation is that the XDomain 348 * discovery protocol UUID cannot be registered since it is handled by 349 * the core XDomain code. 350 * 351 * The @callback must check that the message is really directed to the 352 * service the driver implements. 353 */ 354struct tb_protocol_handler { 355 const uuid_t *uuid; 356 int (*callback)(const void *buf, size_t size, void *data); 357 void *data; 358 struct list_head list; 359}; 360 361int tb_register_protocol_handler(struct tb_protocol_handler *handler); 362void tb_unregister_protocol_handler(struct tb_protocol_handler *handler); 363 364/** 365 * struct tb_service - Thunderbolt service 366 * @dev: XDomain device 367 * @id: ID of the service (shown in sysfs) 368 * @key: Protocol key from the properties directory 369 * @prtcid: Protocol ID from the properties directory 370 * @prtcvers: Protocol version from the properties directory 371 * @prtcrevs: Protocol software revision from the properties directory 372 * @prtcstns: Protocol settings mask from the properties directory 373 * @debugfs_dir: Pointer to the service debugfs directory. Always created 374 * when debugfs is enabled. Can be used by service drivers to 375 * add their own entries under the service. 376 * 377 * Each domain exposes set of services it supports as collection of 378 * properties. For each service there will be one corresponding 379 * &struct tb_service. Service drivers are bound to these. 380 */ 381struct tb_service { 382 struct device dev; 383 int id; 384 const char *key; 385 u32 prtcid; 386 u32 prtcvers; 387 u32 prtcrevs; 388 u32 prtcstns; 389 struct dentry *debugfs_dir; 390}; 391 392static inline struct tb_service *tb_service_get(struct tb_service *svc) 393{ 394 if (svc) 395 get_device(&svc->dev); 396 return svc; 397} 398 399static inline void tb_service_put(struct tb_service *svc) 400{ 401 if (svc) 402 put_device(&svc->dev); 403} 404 405static inline bool tb_is_service(const struct device *dev) 406{ 407 return dev->type == &tb_service_type; 408} 409 410static inline struct tb_service *tb_to_service(struct device *dev) 411{ 412 if (tb_is_service(dev)) 413 return container_of(dev, struct tb_service, dev); 414 return NULL; 415} 416 417/** 418 * tb_service_driver - Thunderbolt service driver 419 * @driver: Driver structure 420 * @probe: Called when the driver is probed 421 * @remove: Called when the driver is removed (optional) 422 * @shutdown: Called at shutdown time to stop the service (optional) 423 * @id_table: Table of service identifiers the driver supports 424 */ 425struct tb_service_driver { 426 struct device_driver driver; 427 int (*probe)(struct tb_service *svc, const struct tb_service_id *id); 428 void (*remove)(struct tb_service *svc); 429 void (*shutdown)(struct tb_service *svc); 430 const struct tb_service_id *id_table; 431}; 432 433#define TB_SERVICE(key, id) \ 434 .match_flags = TBSVC_MATCH_PROTOCOL_KEY | \ 435 TBSVC_MATCH_PROTOCOL_ID, \ 436 .protocol_key = (key), \ 437 .protocol_id = (id) 438 439int tb_register_service_driver(struct tb_service_driver *drv); 440void tb_unregister_service_driver(struct tb_service_driver *drv); 441 442static inline void *tb_service_get_drvdata(const struct tb_service *svc) 443{ 444 return dev_get_drvdata(&svc->dev); 445} 446 447static inline void tb_service_set_drvdata(struct tb_service *svc, void *data) 448{ 449 dev_set_drvdata(&svc->dev, data); 450} 451 452static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc) 453{ 454 return tb_to_xdomain(svc->dev.parent); 455} 456 457/** 458 * struct tb_nhi - thunderbolt native host interface 459 * @lock: Must be held during ring creation/destruction. Is acquired by 460 * interrupt_work when dispatching interrupts to individual rings. 461 * @pdev: Pointer to the PCI device 462 * @ops: NHI specific optional ops 463 * @iobase: MMIO space of the NHI 464 * @tx_rings: All Tx rings available on this host controller 465 * @rx_rings: All Rx rings available on this host controller 466 * @msix_ida: Used to allocate MSI-X vectors for rings 467 * @going_away: The host controller device is about to disappear so when 468 * this flag is set, avoid touching the hardware anymore. 469 * @iommu_dma_protection: An IOMMU will isolate external-facing ports. 470 * @interrupt_work: Work scheduled to handle ring interrupt when no 471 * MSI-X is used. 472 * @hop_count: Number of rings (end point hops) supported by NHI. 473 * @quirks: NHI specific quirks if any 474 */ 475struct tb_nhi { 476 spinlock_t lock; 477 struct pci_dev *pdev; 478 const struct tb_nhi_ops *ops; 479 void __iomem *iobase; 480 struct tb_ring **tx_rings; 481 struct tb_ring **rx_rings; 482 struct ida msix_ida; 483 bool going_away; 484 bool iommu_dma_protection; 485 struct work_struct interrupt_work; 486 u32 hop_count; 487 unsigned long quirks; 488}; 489 490/** 491 * struct tb_ring - thunderbolt TX or RX ring associated with a NHI 492 * @lock: Lock serializing actions to this ring. Must be acquired after 493 * nhi->lock. 494 * @nhi: Pointer to the native host controller interface 495 * @size: Size of the ring 496 * @hop: Hop (DMA channel) associated with this ring 497 * @head: Head of the ring (write next descriptor here) 498 * @tail: Tail of the ring (complete next descriptor here) 499 * @descriptors: Allocated descriptors for this ring 500 * @queue: Queue holding frames to be transferred over this ring 501 * @in_flight: Queue holding frames that are currently in flight 502 * @work: Interrupt work structure 503 * @is_tx: Is the ring Tx or Rx 504 * @running: Is the ring running 505 * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise. 506 * @vector: MSI-X vector number the ring uses (only set if @irq is > 0) 507 * @flags: Ring specific flags 508 * @e2e_tx_hop: Transmit HopID when E2E is enabled. Only applicable to 509 * RX ring. For TX ring this should be set to %0. 510 * @sof_mask: Bit mask used to detect start of frame PDF 511 * @eof_mask: Bit mask used to detect end of frame PDF 512 * @start_poll: Called when ring interrupt is triggered to start 513 * polling. Passing %NULL keeps the ring in interrupt mode. 514 * @poll_data: Data passed to @start_poll 515 */ 516struct tb_ring { 517 spinlock_t lock; 518 struct tb_nhi *nhi; 519 int size; 520 int hop; 521 int head; 522 int tail; 523 struct ring_desc *descriptors; 524 dma_addr_t descriptors_dma; 525 struct list_head queue; 526 struct list_head in_flight; 527 struct work_struct work; 528 bool is_tx:1; 529 bool running:1; 530 int irq; 531 u8 vector; 532 unsigned int flags; 533 int e2e_tx_hop; 534 u16 sof_mask; 535 u16 eof_mask; 536 void (*start_poll)(void *data); 537 void *poll_data; 538}; 539 540/* Leave ring interrupt enabled on suspend */ 541#define RING_FLAG_NO_SUSPEND BIT(0) 542/* Configure the ring to be in frame mode */ 543#define RING_FLAG_FRAME BIT(1) 544/* Enable end-to-end flow control */ 545#define RING_FLAG_E2E BIT(2) 546 547struct ring_frame; 548typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled); 549 550/** 551 * enum ring_desc_flags - Flags for DMA ring descriptor 552 * %RING_DESC_ISOCH: Enable isonchronous DMA (Tx only) 553 * %RING_DESC_CRC_ERROR: In frame mode CRC check failed for the frame (Rx only) 554 * %RING_DESC_COMPLETED: Descriptor completed (set by NHI) 555 * %RING_DESC_POSTED: Always set this 556 * %RING_DESC_BUFFER_OVERRUN: RX buffer overrun 557 * %RING_DESC_INTERRUPT: Request an interrupt on completion 558 */ 559enum ring_desc_flags { 560 RING_DESC_ISOCH = 0x1, 561 RING_DESC_CRC_ERROR = 0x1, 562 RING_DESC_COMPLETED = 0x2, 563 RING_DESC_POSTED = 0x4, 564 RING_DESC_BUFFER_OVERRUN = 0x04, 565 RING_DESC_INTERRUPT = 0x8, 566}; 567 568/** 569 * struct ring_frame - For use with ring_rx/ring_tx 570 * @buffer_phy: DMA mapped address of the frame 571 * @callback: Callback called when the frame is finished (optional) 572 * @list: Frame is linked to a queue using this 573 * @size: Size of the frame in bytes (%0 means %4096) 574 * @flags: Flags for the frame (see &enum ring_desc_flags) 575 * @eof: End of frame protocol defined field 576 * @sof: Start of frame protocol defined field 577 */ 578struct ring_frame { 579 dma_addr_t buffer_phy; 580 ring_cb callback; 581 struct list_head list; 582 u32 size:12; 583 u32 flags:12; 584 u32 eof:4; 585 u32 sof:4; 586}; 587 588/* Minimum size for ring_rx */ 589#define TB_FRAME_SIZE 0x100 590 591struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size, 592 unsigned int flags); 593struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size, 594 unsigned int flags, int e2e_tx_hop, 595 u16 sof_mask, u16 eof_mask, 596 void (*start_poll)(void *), void *poll_data); 597void tb_ring_start(struct tb_ring *ring); 598void tb_ring_stop(struct tb_ring *ring); 599void tb_ring_free(struct tb_ring *ring); 600 601int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame); 602 603/** 604 * tb_ring_rx() - enqueue a frame on an RX ring 605 * @ring: Ring to enqueue the frame 606 * @frame: Frame to enqueue 607 * 608 * @frame->buffer, @frame->buffer_phy have to be set. The buffer must 609 * contain at least %TB_FRAME_SIZE bytes. 610 * 611 * @frame->callback will be invoked with @frame->size, @frame->flags, 612 * @frame->eof, @frame->sof set once the frame has been received. 613 * 614 * If ring_stop() is called after the packet has been enqueued 615 * @frame->callback will be called with canceled set to true. 616 * 617 * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise. 618 */ 619static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame) 620{ 621 WARN_ON(ring->is_tx); 622 return __tb_ring_enqueue(ring, frame); 623} 624 625/** 626 * tb_ring_tx() - enqueue a frame on an TX ring 627 * @ring: Ring the enqueue the frame 628 * @frame: Frame to enqueue 629 * 630 * @frame->buffer, @frame->buffer_phy, @frame->size, @frame->eof and 631 * @frame->sof have to be set. 632 * 633 * @frame->callback will be invoked with once the frame has been transmitted. 634 * 635 * If ring_stop() is called after the packet has been enqueued @frame->callback 636 * will be called with canceled set to true. 637 * 638 * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise. 639 */ 640static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame) 641{ 642 WARN_ON(!ring->is_tx); 643 return __tb_ring_enqueue(ring, frame); 644} 645 646/* Used only when the ring is in polling mode */ 647struct ring_frame *tb_ring_poll(struct tb_ring *ring); 648void tb_ring_poll_complete(struct tb_ring *ring); 649 650/** 651 * tb_ring_dma_device() - Return device used for DMA mapping 652 * @ring: Ring whose DMA device is retrieved 653 * 654 * Use this function when you are mapping DMA for buffers that are 655 * passed to the ring for sending/receiving. 656 */ 657static inline struct device *tb_ring_dma_device(struct tb_ring *ring) 658{ 659 return &ring->nhi->pdev->dev; 660} 661 662#endif /* THUNDERBOLT_H_ */