1 | /* SPDX-License-Identifier: BSD-3-Clause */ |
2 | /* |
3 | * Remote processor messaging |
4 | * |
5 | * Copyright (C) 2011 Texas Instruments, Inc. |
6 | * Copyright (C) 2011 Google, Inc. |
7 | * All rights reserved. |
8 | */ |
9 | |
10 | #ifndef _LINUX_RPMSG_H |
11 | #define _LINUX_RPMSG_H |
12 | |
13 | #include <linux/types.h> |
14 | #include <linux/device.h> |
15 | #include <linux/err.h> |
16 | #include <linux/mod_devicetable.h> |
17 | #include <linux/kref.h> |
18 | #include <linux/mutex.h> |
19 | #include <linux/poll.h> |
20 | #include <linux/rpmsg/byteorder.h> |
21 | #include <uapi/linux/rpmsg.h> |
22 | |
23 | struct rpmsg_device; |
24 | struct rpmsg_endpoint; |
25 | struct rpmsg_device_ops; |
26 | struct rpmsg_endpoint_ops; |
27 | |
28 | /** |
29 | * struct rpmsg_channel_info - channel info representation |
30 | * @name: name of service |
31 | * @src: local address |
32 | * @dst: destination address |
33 | */ |
34 | struct rpmsg_channel_info { |
35 | char name[RPMSG_NAME_SIZE]; |
36 | u32 src; |
37 | u32 dst; |
38 | }; |
39 | |
40 | /** |
41 | * rpmsg_device - device that belong to the rpmsg bus |
42 | * @dev: the device struct |
43 | * @id: device id (used to match between rpmsg drivers and devices) |
44 | * @driver_override: driver name to force a match; do not set directly, |
45 | * because core frees it; use driver_set_override() to |
46 | * set or clear it. |
47 | * @src: local address |
48 | * @dst: destination address |
49 | * @ept: the rpmsg endpoint of this channel |
50 | * @announce: if set, rpmsg will announce the creation/removal of this channel |
51 | * @little_endian: True if transport is using little endian byte representation |
52 | */ |
53 | struct rpmsg_device { |
54 | struct device dev; |
55 | struct rpmsg_device_id id; |
56 | const char *driver_override; |
57 | u32 src; |
58 | u32 dst; |
59 | struct rpmsg_endpoint *ept; |
60 | bool announce; |
61 | bool little_endian; |
62 | |
63 | const struct rpmsg_device_ops *ops; |
64 | }; |
65 | |
66 | typedef int (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32); |
67 | typedef int (*rpmsg_flowcontrol_cb_t)(struct rpmsg_device *, void *, bool); |
68 | |
69 | /** |
70 | * struct rpmsg_endpoint - binds a local rpmsg address to its user |
71 | * @rpdev: rpmsg channel device |
72 | * @refcount: when this drops to zero, the ept is deallocated |
73 | * @cb: rx callback handler |
74 | * @flow_cb: remote flow control callback handler |
75 | * @cb_lock: must be taken before accessing/changing @cb |
76 | * @addr: local rpmsg address |
77 | * @priv: private data for the driver's use |
78 | * |
79 | * In essence, an rpmsg endpoint represents a listener on the rpmsg bus, as |
80 | * it binds an rpmsg address with an rx callback handler. |
81 | * |
82 | * Simple rpmsg drivers shouldn't use this struct directly, because |
83 | * things just work: every rpmsg driver provides an rx callback upon |
84 | * registering to the bus, and that callback is then bound to its rpmsg |
85 | * address when the driver is probed. When relevant inbound messages arrive |
86 | * (i.e. messages which their dst address equals to the src address of |
87 | * the rpmsg channel), the driver's handler is invoked to process it. |
88 | * |
89 | * More complicated drivers though, that do need to allocate additional rpmsg |
90 | * addresses, and bind them to different rx callbacks, must explicitly |
91 | * create additional endpoints by themselves (see rpmsg_create_ept()). |
92 | */ |
93 | struct rpmsg_endpoint { |
94 | struct rpmsg_device *rpdev; |
95 | struct kref refcount; |
96 | rpmsg_rx_cb_t cb; |
97 | rpmsg_flowcontrol_cb_t flow_cb; |
98 | struct mutex cb_lock; |
99 | u32 addr; |
100 | void *priv; |
101 | |
102 | const struct rpmsg_endpoint_ops *ops; |
103 | }; |
104 | |
105 | /** |
106 | * struct rpmsg_driver - rpmsg driver struct |
107 | * @drv: underlying device driver |
108 | * @id_table: rpmsg ids serviced by this driver |
109 | * @probe: invoked when a matching rpmsg channel (i.e. device) is found |
110 | * @remove: invoked when the rpmsg channel is removed |
111 | * @callback: invoked when an inbound message is received on the channel |
112 | * @flowcontrol: invoked when remote side flow control request is received |
113 | */ |
114 | struct rpmsg_driver { |
115 | struct device_driver drv; |
116 | const struct rpmsg_device_id *id_table; |
117 | int (*probe)(struct rpmsg_device *dev); |
118 | void (*remove)(struct rpmsg_device *dev); |
119 | int (*callback)(struct rpmsg_device *, void *, int, void *, u32); |
120 | int (*flowcontrol)(struct rpmsg_device *, void *, bool); |
121 | }; |
122 | |
123 | static inline u16 rpmsg16_to_cpu(struct rpmsg_device *rpdev, __rpmsg16 val) |
124 | { |
125 | if (!rpdev) |
126 | return __rpmsg16_to_cpu(little_endian: rpmsg_is_little_endian(), val); |
127 | else |
128 | return __rpmsg16_to_cpu(little_endian: rpdev->little_endian, val); |
129 | } |
130 | |
131 | static inline __rpmsg16 cpu_to_rpmsg16(struct rpmsg_device *rpdev, u16 val) |
132 | { |
133 | if (!rpdev) |
134 | return __cpu_to_rpmsg16(little_endian: rpmsg_is_little_endian(), val); |
135 | else |
136 | return __cpu_to_rpmsg16(little_endian: rpdev->little_endian, val); |
137 | } |
138 | |
139 | static inline u32 rpmsg32_to_cpu(struct rpmsg_device *rpdev, __rpmsg32 val) |
140 | { |
141 | if (!rpdev) |
142 | return __rpmsg32_to_cpu(little_endian: rpmsg_is_little_endian(), val); |
143 | else |
144 | return __rpmsg32_to_cpu(little_endian: rpdev->little_endian, val); |
145 | } |
146 | |
147 | static inline __rpmsg32 cpu_to_rpmsg32(struct rpmsg_device *rpdev, u32 val) |
148 | { |
149 | if (!rpdev) |
150 | return __cpu_to_rpmsg32(little_endian: rpmsg_is_little_endian(), val); |
151 | else |
152 | return __cpu_to_rpmsg32(little_endian: rpdev->little_endian, val); |
153 | } |
154 | |
155 | static inline u64 rpmsg64_to_cpu(struct rpmsg_device *rpdev, __rpmsg64 val) |
156 | { |
157 | if (!rpdev) |
158 | return __rpmsg64_to_cpu(little_endian: rpmsg_is_little_endian(), val); |
159 | else |
160 | return __rpmsg64_to_cpu(little_endian: rpdev->little_endian, val); |
161 | } |
162 | |
163 | static inline __rpmsg64 cpu_to_rpmsg64(struct rpmsg_device *rpdev, u64 val) |
164 | { |
165 | if (!rpdev) |
166 | return __cpu_to_rpmsg64(little_endian: rpmsg_is_little_endian(), val); |
167 | else |
168 | return __cpu_to_rpmsg64(little_endian: rpdev->little_endian, val); |
169 | } |
170 | |
171 | #if IS_ENABLED(CONFIG_RPMSG) |
172 | |
173 | int rpmsg_register_device_override(struct rpmsg_device *rpdev, |
174 | const char *driver_override); |
175 | int rpmsg_register_device(struct rpmsg_device *rpdev); |
176 | int rpmsg_unregister_device(struct device *parent, |
177 | struct rpmsg_channel_info *chinfo); |
178 | int __register_rpmsg_driver(struct rpmsg_driver *drv, struct module *owner); |
179 | void unregister_rpmsg_driver(struct rpmsg_driver *drv); |
180 | void rpmsg_destroy_ept(struct rpmsg_endpoint *); |
181 | struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *, |
182 | rpmsg_rx_cb_t cb, void *priv, |
183 | struct rpmsg_channel_info chinfo); |
184 | |
185 | int rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len); |
186 | int rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); |
187 | int rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, |
188 | void *data, int len); |
189 | |
190 | int rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len); |
191 | int rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); |
192 | int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, |
193 | void *data, int len); |
194 | |
195 | __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, |
196 | poll_table *wait); |
197 | |
198 | ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); |
199 | |
200 | int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst); |
201 | |
202 | #else |
203 | |
204 | static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev, |
205 | const char *driver_override) |
206 | { |
207 | return -ENXIO; |
208 | } |
209 | |
210 | static inline int rpmsg_register_device(struct rpmsg_device *rpdev) |
211 | { |
212 | return -ENXIO; |
213 | } |
214 | |
215 | static inline int rpmsg_unregister_device(struct device *parent, |
216 | struct rpmsg_channel_info *chinfo) |
217 | { |
218 | /* This shouldn't be possible */ |
219 | WARN_ON(1); |
220 | |
221 | return -ENXIO; |
222 | } |
223 | |
224 | static inline int __register_rpmsg_driver(struct rpmsg_driver *drv, |
225 | struct module *owner) |
226 | { |
227 | /* This shouldn't be possible */ |
228 | WARN_ON(1); |
229 | |
230 | return -ENXIO; |
231 | } |
232 | |
233 | static inline void unregister_rpmsg_driver(struct rpmsg_driver *drv) |
234 | { |
235 | /* This shouldn't be possible */ |
236 | WARN_ON(1); |
237 | } |
238 | |
239 | static inline void rpmsg_destroy_ept(struct rpmsg_endpoint *ept) |
240 | { |
241 | /* This shouldn't be possible */ |
242 | WARN_ON(1); |
243 | } |
244 | |
245 | static inline struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *rpdev, |
246 | rpmsg_rx_cb_t cb, |
247 | void *priv, |
248 | struct rpmsg_channel_info chinfo) |
249 | { |
250 | /* This shouldn't be possible */ |
251 | WARN_ON(1); |
252 | |
253 | return NULL; |
254 | } |
255 | |
256 | static inline int rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len) |
257 | { |
258 | /* This shouldn't be possible */ |
259 | WARN_ON(1); |
260 | |
261 | return -ENXIO; |
262 | } |
263 | |
264 | static inline int rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, |
265 | u32 dst) |
266 | { |
267 | /* This shouldn't be possible */ |
268 | WARN_ON(1); |
269 | |
270 | return -ENXIO; |
271 | |
272 | } |
273 | |
274 | static inline int rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, |
275 | u32 dst, void *data, int len) |
276 | { |
277 | /* This shouldn't be possible */ |
278 | WARN_ON(1); |
279 | |
280 | return -ENXIO; |
281 | } |
282 | |
283 | static inline int rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len) |
284 | { |
285 | /* This shouldn't be possible */ |
286 | WARN_ON(1); |
287 | |
288 | return -ENXIO; |
289 | } |
290 | |
291 | static inline int rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, |
292 | int len, u32 dst) |
293 | { |
294 | /* This shouldn't be possible */ |
295 | WARN_ON(1); |
296 | |
297 | return -ENXIO; |
298 | } |
299 | |
300 | static inline int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, |
301 | u32 dst, void *data, int len) |
302 | { |
303 | /* This shouldn't be possible */ |
304 | WARN_ON(1); |
305 | |
306 | return -ENXIO; |
307 | } |
308 | |
309 | static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, |
310 | struct file *filp, poll_table *wait) |
311 | { |
312 | /* This shouldn't be possible */ |
313 | WARN_ON(1); |
314 | |
315 | return 0; |
316 | } |
317 | |
318 | static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) |
319 | { |
320 | /* This shouldn't be possible */ |
321 | WARN_ON(1); |
322 | |
323 | return -ENXIO; |
324 | } |
325 | |
326 | static inline int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst) |
327 | { |
328 | /* This shouldn't be possible */ |
329 | WARN_ON(1); |
330 | |
331 | return -ENXIO; |
332 | } |
333 | |
334 | #endif /* IS_ENABLED(CONFIG_RPMSG) */ |
335 | |
336 | /* use a macro to avoid include chaining to get THIS_MODULE */ |
337 | #define register_rpmsg_driver(drv) \ |
338 | __register_rpmsg_driver(drv, THIS_MODULE) |
339 | |
340 | /** |
341 | * module_rpmsg_driver() - Helper macro for registering an rpmsg driver |
342 | * @__rpmsg_driver: rpmsg_driver struct |
343 | * |
344 | * Helper macro for rpmsg drivers which do not do anything special in module |
345 | * init/exit. This eliminates a lot of boilerplate. Each module may only |
346 | * use this macro once, and calling it replaces module_init() and module_exit() |
347 | */ |
348 | #define module_rpmsg_driver(__rpmsg_driver) \ |
349 | module_driver(__rpmsg_driver, register_rpmsg_driver, \ |
350 | unregister_rpmsg_driver) |
351 | |
352 | #endif /* _LINUX_RPMSG_H */ |
353 | |