1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Greybus connections
4  *
5  * Copyright 2014 Google Inc.
6  * Copyright 2014 Linaro Ltd.
7  */
8 
9 #ifndef __CONNECTION_H
10 #define __CONNECTION_H
11 
12 #include <linux/bits.h>
13 #include <linux/list.h>
14 #include <linux/kfifo.h>
15 #include <linux/kref.h>
16 #include <linux/workqueue.h>
17 
18 #define GB_CONNECTION_FLAG_CSD		BIT(0)
19 #define GB_CONNECTION_FLAG_NO_FLOWCTRL	BIT(1)
20 #define GB_CONNECTION_FLAG_OFFLOADED	BIT(2)
21 #define GB_CONNECTION_FLAG_CDSI1	BIT(3)
22 #define GB_CONNECTION_FLAG_CONTROL	BIT(4)
23 #define GB_CONNECTION_FLAG_HIGH_PRIO	BIT(5)
24 
25 #define GB_CONNECTION_FLAG_CORE_MASK	GB_CONNECTION_FLAG_CONTROL
26 
27 enum gb_connection_state {
28 	GB_CONNECTION_STATE_DISABLED		= 0,
29 	GB_CONNECTION_STATE_ENABLED_TX		= 1,
30 	GB_CONNECTION_STATE_ENABLED		= 2,
31 	GB_CONNECTION_STATE_DISCONNECTING	= 3,
32 };
33 
34 struct gb_operation;
35 
36 typedef int (*gb_request_handler_t)(struct gb_operation *);
37 
38 struct gb_connection {
39 	struct gb_host_device		*hd;
40 	struct gb_interface		*intf;
41 	struct gb_bundle		*bundle;
42 	struct kref			kref;
43 	u16				hd_cport_id;
44 	u16				intf_cport_id;
45 
46 	struct list_head		hd_links;
47 	struct list_head		bundle_links;
48 
49 	gb_request_handler_t		handler;
50 	unsigned long			flags;
51 
52 	struct mutex			mutex;
53 	spinlock_t			lock;
54 	enum gb_connection_state	state;
55 	struct list_head		operations;
56 
57 	char				name[16];
58 	struct workqueue_struct		*wq;
59 
60 	atomic_t			op_cycle;
61 
62 	void				*private;
63 
64 	bool				mode_switch;
65 };
66 
67 struct gb_connection *gb_connection_create_static(struct gb_host_device *hd,
68 				u16 hd_cport_id, gb_request_handler_t handler);
69 struct gb_connection *gb_connection_create_control(struct gb_interface *intf);
70 struct gb_connection *gb_connection_create(struct gb_bundle *bundle,
71 				u16 cport_id, gb_request_handler_t handler);
72 struct gb_connection *gb_connection_create_flags(struct gb_bundle *bundle,
73 				u16 cport_id, gb_request_handler_t handler,
74 				unsigned long flags);
75 struct gb_connection *gb_connection_create_offloaded(struct gb_bundle *bundle,
76 				u16 cport_id, unsigned long flags);
77 void gb_connection_destroy(struct gb_connection *connection);
78 
gb_connection_is_static(struct gb_connection * connection)79 static inline bool gb_connection_is_static(struct gb_connection *connection)
80 {
81 	return !connection->intf;
82 }
83 
84 int gb_connection_enable(struct gb_connection *connection);
85 int gb_connection_enable_tx(struct gb_connection *connection);
86 void gb_connection_disable_rx(struct gb_connection *connection);
87 void gb_connection_disable(struct gb_connection *connection);
88 void gb_connection_disable_forced(struct gb_connection *connection);
89 
90 void gb_connection_mode_switch_prepare(struct gb_connection *connection);
91 void gb_connection_mode_switch_complete(struct gb_connection *connection);
92 
93 void greybus_data_rcvd(struct gb_host_device *hd, u16 cport_id,
94 		       u8 *data, size_t length);
95 
96 void gb_connection_latency_tag_enable(struct gb_connection *connection);
97 void gb_connection_latency_tag_disable(struct gb_connection *connection);
98 
gb_connection_e2efc_enabled(struct gb_connection * connection)99 static inline bool gb_connection_e2efc_enabled(struct gb_connection *connection)
100 {
101 	return !(connection->flags & GB_CONNECTION_FLAG_CSD);
102 }
103 
104 static inline bool
gb_connection_flow_control_disabled(struct gb_connection * connection)105 gb_connection_flow_control_disabled(struct gb_connection *connection)
106 {
107 	return connection->flags & GB_CONNECTION_FLAG_NO_FLOWCTRL;
108 }
109 
gb_connection_is_offloaded(struct gb_connection * connection)110 static inline bool gb_connection_is_offloaded(struct gb_connection *connection)
111 {
112 	return connection->flags & GB_CONNECTION_FLAG_OFFLOADED;
113 }
114 
gb_connection_is_control(struct gb_connection * connection)115 static inline bool gb_connection_is_control(struct gb_connection *connection)
116 {
117 	return connection->flags & GB_CONNECTION_FLAG_CONTROL;
118 }
119 
gb_connection_get_data(struct gb_connection * connection)120 static inline void *gb_connection_get_data(struct gb_connection *connection)
121 {
122 	return connection->private;
123 }
124 
gb_connection_set_data(struct gb_connection * connection,void * data)125 static inline void gb_connection_set_data(struct gb_connection *connection,
126 					  void *data)
127 {
128 	connection->private = data;
129 }
130 
131 #endif /* __CONNECTION_H */
132