1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Thunderbolt driver - control channel and configuration commands
4 *
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6 * Copyright (C) 2018, Intel Corporation
7 */
8
9#ifndef _TB_CFG
10#define _TB_CFG
11
12#include <linux/kref.h>
13#include <linux/thunderbolt.h>
14
15#include "nhi.h"
16#include "tb_msgs.h"
17
18/* control channel */
19struct tb_ctl;
20
21typedef bool (*event_cb)(void *data, enum tb_cfg_pkg_type type,
22			 const void *buf, size_t size);
23
24struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data);
25void tb_ctl_start(struct tb_ctl *ctl);
26void tb_ctl_stop(struct tb_ctl *ctl);
27void tb_ctl_free(struct tb_ctl *ctl);
28
29/* configuration commands */
30
31#define TB_CFG_DEFAULT_TIMEOUT 5000 /* msec */
32
33struct tb_cfg_result {
34	u64 response_route;
35	u32 response_port; /*
36			    * If err = 1 then this is the port that send the
37			    * error.
38			    * If err = 0 and if this was a cfg_read/write then
39			    * this is the the upstream port of the responding
40			    * switch.
41			    * Otherwise the field is set to zero.
42			    */
43	int err; /* negative errors, 0 for success, 1 for tb errors */
44	enum tb_cfg_error tb_error; /* valid if err == 1 */
45};
46
47struct ctl_pkg {
48	struct tb_ctl *ctl;
49	void *buffer;
50	struct ring_frame frame;
51};
52
53/**
54 * struct tb_cfg_request - Control channel request
55 * @kref: Reference count
56 * @ctl: Pointer to the control channel structure. Only set when the
57 *	 request is queued.
58 * @request_size: Size of the request packet (in bytes)
59 * @request_type: Type of the request packet
60 * @response: Response is stored here
61 * @response_size: Maximum size of one response packet
62 * @response_type: Expected type of the response packet
63 * @npackets: Number of packets expected to be returned with this request
64 * @match: Function used to match the incoming packet
65 * @copy: Function used to copy the incoming packet to @response
66 * @callback: Callback called when the request is finished successfully
67 * @callback_data: Data to be passed to @callback
68 * @flags: Flags for the request
69 * @work: Work item used to complete the request
70 * @result: Result after the request has been completed
71 * @list: Requests are queued using this field
72 *
73 * An arbitrary request over Thunderbolt control channel. For standard
74 * control channel message, one should use tb_cfg_read/write() and
75 * friends if possible.
76 */
77struct tb_cfg_request {
78	struct kref kref;
79	struct tb_ctl *ctl;
80	const void *request;
81	size_t request_size;
82	enum tb_cfg_pkg_type request_type;
83	void *response;
84	size_t response_size;
85	enum tb_cfg_pkg_type response_type;
86	size_t npackets;
87	bool (*match)(const struct tb_cfg_request *req,
88		      const struct ctl_pkg *pkg);
89	bool (*copy)(struct tb_cfg_request *req, const struct ctl_pkg *pkg);
90	void (*callback)(void *callback_data);
91	void *callback_data;
92	unsigned long flags;
93	struct work_struct work;
94	struct tb_cfg_result result;
95	struct list_head list;
96};
97
98#define TB_CFG_REQUEST_ACTIVE		0
99#define TB_CFG_REQUEST_CANCELED		1
100
101struct tb_cfg_request *tb_cfg_request_alloc(void);
102void tb_cfg_request_get(struct tb_cfg_request *req);
103void tb_cfg_request_put(struct tb_cfg_request *req);
104int tb_cfg_request(struct tb_ctl *ctl, struct tb_cfg_request *req,
105		   void (*callback)(void *), void *callback_data);
106void tb_cfg_request_cancel(struct tb_cfg_request *req, int err);
107struct tb_cfg_result tb_cfg_request_sync(struct tb_ctl *ctl,
108			struct tb_cfg_request *req, int timeout_msec);
109
110static inline u64 tb_cfg_get_route(const struct tb_cfg_header *header)
111{
112	return (u64) header->route_hi << 32 | header->route_lo;
113}
114
115static inline struct tb_cfg_header tb_cfg_make_header(u64 route)
116{
117	struct tb_cfg_header header = {
118		.route_hi = route >> 32,
119		.route_lo = route,
120	};
121	/* check for overflow, route_hi is not 32 bits! */
122	WARN_ON(tb_cfg_get_route(&header) != route);
123	return header;
124}
125
126int tb_cfg_ack_plug(struct tb_ctl *ctl, u64 route, u32 port, bool unplug);
127struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route,
128				  int timeout_msec);
129struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer,
130				     u64 route, u32 port,
131				     enum tb_cfg_space space, u32 offset,
132				     u32 length, int timeout_msec);
133struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, const void *buffer,
134				      u64 route, u32 port,
135				      enum tb_cfg_space space, u32 offset,
136				      u32 length, int timeout_msec);
137int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
138		enum tb_cfg_space space, u32 offset, u32 length);
139int tb_cfg_write(struct tb_ctl *ctl, const void *buffer, u64 route, u32 port,
140		 enum tb_cfg_space space, u32 offset, u32 length);
141int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route);
142
143
144#endif
145