]> git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - include/linux/thunderbolt.h
Merge tag 'fs.move_mount.move_mount_set_group.v5.15' of git://git.kernel.org/pub...
[mirror_ubuntu-jammy-kernel.git] / include / linux / thunderbolt.h
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
23 enum 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 */
51 enum 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 */
75 struct 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
89 extern struct bus_type tb_bus_type;
90 extern struct device_type tb_service_type;
91 extern struct device_type tb_xdomain_type;
92
93 #define TB_LINKS_PER_PHY_PORT 2
94
95 static 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 */
107 struct tb_property_dir {
108 const uuid_t *uuid;
109 struct list_head properties;
110 };
111
112 enum 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 */
132 struct 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
145 struct tb_property_dir *tb_property_parse_dir(const u32 *block,
146 size_t block_len);
147 ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block,
148 size_t block_len);
149 struct tb_property_dir *tb_property_copy_dir(const struct tb_property_dir *dir);
150 struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid);
151 void tb_property_free_dir(struct tb_property_dir *dir);
152 int tb_property_add_immediate(struct tb_property_dir *parent, const char *key,
153 u32 value);
154 int tb_property_add_data(struct tb_property_dir *parent, const char *key,
155 const void *buf, size_t buflen);
156 int tb_property_add_text(struct tb_property_dir *parent, const char *key,
157 const char *text);
158 int tb_property_add_dir(struct tb_property_dir *parent, const char *key,
159 struct tb_property_dir *dir);
160 void tb_property_remove(struct tb_property *tb_property);
161 struct tb_property *tb_property_find(struct tb_property_dir *dir,
162 const char *key, enum tb_property_type type);
163 struct 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
171 int tb_register_property_dir(const char *key, struct tb_property_dir *dir);
172 void 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 * @get_uuid_work: Work used to retrieve @remote_uuid
202 * @uuid_retries: Number of times left @remote_uuid is requested before
203 * giving up
204 * @get_properties_work: Work used to get remote domain properties
205 * @properties_retries: Number of times left to read properties
206 * @properties_changed_work: Work used to notify the remote domain that
207 * our properties have changed
208 * @properties_changed_retries: Number of times left to send properties
209 * changed notification
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 */
222 struct 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 struct delayed_work get_uuid_work;
248 int uuid_retries;
249 struct delayed_work get_properties_work;
250 int properties_retries;
251 struct delayed_work properties_changed_work;
252 int properties_changed_retries;
253 u8 link;
254 u8 depth;
255 };
256
257 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd);
258 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd);
259 int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid);
260 void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid);
261 int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid);
262 void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid);
263 int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
264 int transmit_ring, int receive_path,
265 int receive_ring);
266 int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
267 int transmit_ring, int receive_path,
268 int receive_ring);
269
270 static inline int tb_xdomain_disable_all_paths(struct tb_xdomain *xd)
271 {
272 return tb_xdomain_disable_paths(xd, -1, -1, -1, -1);
273 }
274
275 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid);
276 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route);
277
278 static inline struct tb_xdomain *
279 tb_xdomain_find_by_uuid_locked(struct tb *tb, const uuid_t *uuid)
280 {
281 struct tb_xdomain *xd;
282
283 mutex_lock(&tb->lock);
284 xd = tb_xdomain_find_by_uuid(tb, uuid);
285 mutex_unlock(&tb->lock);
286
287 return xd;
288 }
289
290 static inline struct tb_xdomain *
291 tb_xdomain_find_by_route_locked(struct tb *tb, u64 route)
292 {
293 struct tb_xdomain *xd;
294
295 mutex_lock(&tb->lock);
296 xd = tb_xdomain_find_by_route(tb, route);
297 mutex_unlock(&tb->lock);
298
299 return xd;
300 }
301
302 static inline struct tb_xdomain *tb_xdomain_get(struct tb_xdomain *xd)
303 {
304 if (xd)
305 get_device(&xd->dev);
306 return xd;
307 }
308
309 static inline void tb_xdomain_put(struct tb_xdomain *xd)
310 {
311 if (xd)
312 put_device(&xd->dev);
313 }
314
315 static inline bool tb_is_xdomain(const struct device *dev)
316 {
317 return dev->type == &tb_xdomain_type;
318 }
319
320 static inline struct tb_xdomain *tb_to_xdomain(struct device *dev)
321 {
322 if (tb_is_xdomain(dev))
323 return container_of(dev, struct tb_xdomain, dev);
324 return NULL;
325 }
326
327 int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
328 size_t size, enum tb_cfg_pkg_type type);
329 int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
330 size_t request_size, enum tb_cfg_pkg_type request_type,
331 void *response, size_t response_size,
332 enum tb_cfg_pkg_type response_type,
333 unsigned int timeout_msec);
334
335 /**
336 * tb_protocol_handler - Protocol specific handler
337 * @uuid: XDomain messages with this UUID are dispatched to this handler
338 * @callback: Callback called with the XDomain message. Returning %1
339 * here tells the XDomain core that the message was handled
340 * by this handler and should not be forwared to other
341 * handlers.
342 * @data: Data passed with the callback
343 * @list: Handlers are linked using this
344 *
345 * Thunderbolt services can hook into incoming XDomain requests by
346 * registering protocol handler. Only limitation is that the XDomain
347 * discovery protocol UUID cannot be registered since it is handled by
348 * the core XDomain code.
349 *
350 * The @callback must check that the message is really directed to the
351 * service the driver implements.
352 */
353 struct tb_protocol_handler {
354 const uuid_t *uuid;
355 int (*callback)(const void *buf, size_t size, void *data);
356 void *data;
357 struct list_head list;
358 };
359
360 int tb_register_protocol_handler(struct tb_protocol_handler *handler);
361 void tb_unregister_protocol_handler(struct tb_protocol_handler *handler);
362
363 /**
364 * struct tb_service - Thunderbolt service
365 * @dev: XDomain device
366 * @id: ID of the service (shown in sysfs)
367 * @key: Protocol key from the properties directory
368 * @prtcid: Protocol ID from the properties directory
369 * @prtcvers: Protocol version from the properties directory
370 * @prtcrevs: Protocol software revision from the properties directory
371 * @prtcstns: Protocol settings mask from the properties directory
372 * @debugfs_dir: Pointer to the service debugfs directory. Always created
373 * when debugfs is enabled. Can be used by service drivers to
374 * add their own entries under the service.
375 *
376 * Each domain exposes set of services it supports as collection of
377 * properties. For each service there will be one corresponding
378 * &struct tb_service. Service drivers are bound to these.
379 */
380 struct tb_service {
381 struct device dev;
382 int id;
383 const char *key;
384 u32 prtcid;
385 u32 prtcvers;
386 u32 prtcrevs;
387 u32 prtcstns;
388 struct dentry *debugfs_dir;
389 };
390
391 static inline struct tb_service *tb_service_get(struct tb_service *svc)
392 {
393 if (svc)
394 get_device(&svc->dev);
395 return svc;
396 }
397
398 static inline void tb_service_put(struct tb_service *svc)
399 {
400 if (svc)
401 put_device(&svc->dev);
402 }
403
404 static inline bool tb_is_service(const struct device *dev)
405 {
406 return dev->type == &tb_service_type;
407 }
408
409 static inline struct tb_service *tb_to_service(struct device *dev)
410 {
411 if (tb_is_service(dev))
412 return container_of(dev, struct tb_service, dev);
413 return NULL;
414 }
415
416 /**
417 * tb_service_driver - Thunderbolt service driver
418 * @driver: Driver structure
419 * @probe: Called when the driver is probed
420 * @remove: Called when the driver is removed (optional)
421 * @shutdown: Called at shutdown time to stop the service (optional)
422 * @id_table: Table of service identifiers the driver supports
423 */
424 struct tb_service_driver {
425 struct device_driver driver;
426 int (*probe)(struct tb_service *svc, const struct tb_service_id *id);
427 void (*remove)(struct tb_service *svc);
428 void (*shutdown)(struct tb_service *svc);
429 const struct tb_service_id *id_table;
430 };
431
432 #define TB_SERVICE(key, id) \
433 .match_flags = TBSVC_MATCH_PROTOCOL_KEY | \
434 TBSVC_MATCH_PROTOCOL_ID, \
435 .protocol_key = (key), \
436 .protocol_id = (id)
437
438 int tb_register_service_driver(struct tb_service_driver *drv);
439 void tb_unregister_service_driver(struct tb_service_driver *drv);
440
441 static inline void *tb_service_get_drvdata(const struct tb_service *svc)
442 {
443 return dev_get_drvdata(&svc->dev);
444 }
445
446 static inline void tb_service_set_drvdata(struct tb_service *svc, void *data)
447 {
448 dev_set_drvdata(&svc->dev, data);
449 }
450
451 static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
452 {
453 return tb_to_xdomain(svc->dev.parent);
454 }
455
456 /**
457 * struct tb_nhi - thunderbolt native host interface
458 * @lock: Must be held during ring creation/destruction. Is acquired by
459 * interrupt_work when dispatching interrupts to individual rings.
460 * @pdev: Pointer to the PCI device
461 * @ops: NHI specific optional ops
462 * @iobase: MMIO space of the NHI
463 * @tx_rings: All Tx rings available on this host controller
464 * @rx_rings: All Rx rings available on this host controller
465 * @msix_ida: Used to allocate MSI-X vectors for rings
466 * @going_away: The host controller device is about to disappear so when
467 * this flag is set, avoid touching the hardware anymore.
468 * @interrupt_work: Work scheduled to handle ring interrupt when no
469 * MSI-X is used.
470 * @hop_count: Number of rings (end point hops) supported by NHI.
471 */
472 struct tb_nhi {
473 spinlock_t lock;
474 struct pci_dev *pdev;
475 const struct tb_nhi_ops *ops;
476 void __iomem *iobase;
477 struct tb_ring **tx_rings;
478 struct tb_ring **rx_rings;
479 struct ida msix_ida;
480 bool going_away;
481 struct work_struct interrupt_work;
482 u32 hop_count;
483 };
484
485 /**
486 * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
487 * @lock: Lock serializing actions to this ring. Must be acquired after
488 * nhi->lock.
489 * @nhi: Pointer to the native host controller interface
490 * @size: Size of the ring
491 * @hop: Hop (DMA channel) associated with this ring
492 * @head: Head of the ring (write next descriptor here)
493 * @tail: Tail of the ring (complete next descriptor here)
494 * @descriptors: Allocated descriptors for this ring
495 * @queue: Queue holding frames to be transferred over this ring
496 * @in_flight: Queue holding frames that are currently in flight
497 * @work: Interrupt work structure
498 * @is_tx: Is the ring Tx or Rx
499 * @running: Is the ring running
500 * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
501 * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
502 * @flags: Ring specific flags
503 * @e2e_tx_hop: Transmit HopID when E2E is enabled. Only applicable to
504 * RX ring. For TX ring this should be set to %0.
505 * @sof_mask: Bit mask used to detect start of frame PDF
506 * @eof_mask: Bit mask used to detect end of frame PDF
507 * @start_poll: Called when ring interrupt is triggered to start
508 * polling. Passing %NULL keeps the ring in interrupt mode.
509 * @poll_data: Data passed to @start_poll
510 */
511 struct tb_ring {
512 spinlock_t lock;
513 struct tb_nhi *nhi;
514 int size;
515 int hop;
516 int head;
517 int tail;
518 struct ring_desc *descriptors;
519 dma_addr_t descriptors_dma;
520 struct list_head queue;
521 struct list_head in_flight;
522 struct work_struct work;
523 bool is_tx:1;
524 bool running:1;
525 int irq;
526 u8 vector;
527 unsigned int flags;
528 int e2e_tx_hop;
529 u16 sof_mask;
530 u16 eof_mask;
531 void (*start_poll)(void *data);
532 void *poll_data;
533 };
534
535 /* Leave ring interrupt enabled on suspend */
536 #define RING_FLAG_NO_SUSPEND BIT(0)
537 /* Configure the ring to be in frame mode */
538 #define RING_FLAG_FRAME BIT(1)
539 /* Enable end-to-end flow control */
540 #define RING_FLAG_E2E BIT(2)
541
542 struct ring_frame;
543 typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);
544
545 /**
546 * enum ring_desc_flags - Flags for DMA ring descriptor
547 * %RING_DESC_ISOCH: Enable isonchronous DMA (Tx only)
548 * %RING_DESC_CRC_ERROR: In frame mode CRC check failed for the frame (Rx only)
549 * %RING_DESC_COMPLETED: Descriptor completed (set by NHI)
550 * %RING_DESC_POSTED: Always set this
551 * %RING_DESC_BUFFER_OVERRUN: RX buffer overrun
552 * %RING_DESC_INTERRUPT: Request an interrupt on completion
553 */
554 enum ring_desc_flags {
555 RING_DESC_ISOCH = 0x1,
556 RING_DESC_CRC_ERROR = 0x1,
557 RING_DESC_COMPLETED = 0x2,
558 RING_DESC_POSTED = 0x4,
559 RING_DESC_BUFFER_OVERRUN = 0x04,
560 RING_DESC_INTERRUPT = 0x8,
561 };
562
563 /**
564 * struct ring_frame - For use with ring_rx/ring_tx
565 * @buffer_phy: DMA mapped address of the frame
566 * @callback: Callback called when the frame is finished (optional)
567 * @list: Frame is linked to a queue using this
568 * @size: Size of the frame in bytes (%0 means %4096)
569 * @flags: Flags for the frame (see &enum ring_desc_flags)
570 * @eof: End of frame protocol defined field
571 * @sof: Start of frame protocol defined field
572 */
573 struct ring_frame {
574 dma_addr_t buffer_phy;
575 ring_cb callback;
576 struct list_head list;
577 u32 size:12;
578 u32 flags:12;
579 u32 eof:4;
580 u32 sof:4;
581 };
582
583 /* Minimum size for ring_rx */
584 #define TB_FRAME_SIZE 0x100
585
586 struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
587 unsigned int flags);
588 struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
589 unsigned int flags, int e2e_tx_hop,
590 u16 sof_mask, u16 eof_mask,
591 void (*start_poll)(void *), void *poll_data);
592 void tb_ring_start(struct tb_ring *ring);
593 void tb_ring_stop(struct tb_ring *ring);
594 void tb_ring_free(struct tb_ring *ring);
595
596 int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
597
598 /**
599 * tb_ring_rx() - enqueue a frame on an RX ring
600 * @ring: Ring to enqueue the frame
601 * @frame: Frame to enqueue
602 *
603 * @frame->buffer, @frame->buffer_phy have to be set. The buffer must
604 * contain at least %TB_FRAME_SIZE bytes.
605 *
606 * @frame->callback will be invoked with @frame->size, @frame->flags,
607 * @frame->eof, @frame->sof set once the frame has been received.
608 *
609 * If ring_stop() is called after the packet has been enqueued
610 * @frame->callback will be called with canceled set to true.
611 *
612 * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
613 */
614 static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
615 {
616 WARN_ON(ring->is_tx);
617 return __tb_ring_enqueue(ring, frame);
618 }
619
620 /**
621 * tb_ring_tx() - enqueue a frame on an TX ring
622 * @ring: Ring the enqueue the frame
623 * @frame: Frame to enqueue
624 *
625 * @frame->buffer, @frame->buffer_phy, @frame->size, @frame->eof and
626 * @frame->sof have to be set.
627 *
628 * @frame->callback will be invoked with once the frame has been transmitted.
629 *
630 * If ring_stop() is called after the packet has been enqueued @frame->callback
631 * will be called with canceled set to true.
632 *
633 * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
634 */
635 static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
636 {
637 WARN_ON(!ring->is_tx);
638 return __tb_ring_enqueue(ring, frame);
639 }
640
641 /* Used only when the ring is in polling mode */
642 struct ring_frame *tb_ring_poll(struct tb_ring *ring);
643 void tb_ring_poll_complete(struct tb_ring *ring);
644
645 /**
646 * tb_ring_dma_device() - Return device used for DMA mapping
647 * @ring: Ring whose DMA device is retrieved
648 *
649 * Use this function when you are mapping DMA for buffers that are
650 * passed to the ring for sending/receiving.
651 */
652 static inline struct device *tb_ring_dma_device(struct tb_ring *ring)
653 {
654 return &ring->nhi->pdev->dev;
655 }
656
657 #endif /* THUNDERBOLT_H_ */