xref: /openbmc/linux/drivers/thunderbolt/ctl.h (revision d9fd5a71)
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 */
19 struct tb_ctl;
20 
21 typedef bool (*event_cb)(void *data, enum tb_cfg_pkg_type type,
22 			 const void *buf, size_t size);
23 
24 struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data);
25 void tb_ctl_start(struct tb_ctl *ctl);
26 void tb_ctl_stop(struct tb_ctl *ctl);
27 void tb_ctl_free(struct tb_ctl *ctl);
28 
29 /* configuration commands */
30 
31 #define TB_CFG_DEFAULT_TIMEOUT 5000 /* msec */
32 
33 struct 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 
47 struct 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  */
77 struct 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 
101 struct tb_cfg_request *tb_cfg_request_alloc(void);
102 void tb_cfg_request_get(struct tb_cfg_request *req);
103 void tb_cfg_request_put(struct tb_cfg_request *req);
104 int tb_cfg_request(struct tb_ctl *ctl, struct tb_cfg_request *req,
105 		   void (*callback)(void *), void *callback_data);
106 void tb_cfg_request_cancel(struct tb_cfg_request *req, int err);
107 struct tb_cfg_result tb_cfg_request_sync(struct tb_ctl *ctl,
108 			struct tb_cfg_request *req, int timeout_msec);
109 
110 static 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 
115 static 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 
126 int tb_cfg_ack_plug(struct tb_ctl *ctl, u64 route, u32 port, bool unplug);
127 struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route,
128 				  int timeout_msec);
129 struct 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);
133 struct 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);
137 int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
138 		enum tb_cfg_space space, u32 offset, u32 length);
139 int tb_cfg_write(struct tb_ctl *ctl, const void *buffer, u64 route, u32 port,
140 		 enum tb_cfg_space space, u32 offset, u32 length);
141 int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route);
142 
143 
144 #endif
145