drivers/thunderbolt/ctl.h

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