1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * HSI core header file.
4 *
5 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
6 *
7 * Contact: Carlos Chinea <carlos.chinea@nokia.com>
8 */
9
10 #ifndef __LINUX_HSI_H__
11 #define __LINUX_HSI_H__
12
13 #include <linux/device.h>
14 #include <linux/mutex.h>
15 #include <linux/scatterlist.h>
16 #include <linux/list.h>
17 #include <linux/module.h>
18 #include <linux/notifier.h>
19
20 /* HSI message ttype */
21 #define HSI_MSG_READ 0
22 #define HSI_MSG_WRITE 1
23
24 /* HSI configuration values */
25 enum {
26 HSI_MODE_STREAM = 1,
27 HSI_MODE_FRAME,
28 };
29
30 enum {
31 HSI_FLOW_SYNC, /* Synchronized flow */
32 HSI_FLOW_PIPE, /* Pipelined flow */
33 };
34
35 enum {
36 HSI_ARB_RR, /* Round-robin arbitration */
37 HSI_ARB_PRIO, /* Channel priority arbitration */
38 };
39
40 #define HSI_MAX_CHANNELS 16
41
42 /* HSI message status codes */
43 enum {
44 HSI_STATUS_COMPLETED, /* Message transfer is completed */
45 HSI_STATUS_PENDING, /* Message pending to be read/write (POLL) */
46 HSI_STATUS_PROCEEDING, /* Message transfer is ongoing */
47 HSI_STATUS_QUEUED, /* Message waiting to be served */
48 HSI_STATUS_ERROR, /* Error when message transfer was ongoing */
49 };
50
51 /* HSI port event codes */
52 enum {
53 HSI_EVENT_START_RX,
54 HSI_EVENT_STOP_RX,
55 };
56
57 /**
58 * struct hsi_channel - channel resource used by the hsi clients
59 * @id: Channel number
60 * @name: Channel name
61 */
62 struct hsi_channel {
63 unsigned int id;
64 const char *name;
65 };
66
67 /**
68 * struct hsi_config - Configuration for RX/TX HSI modules
69 * @mode: Bit transmission mode (STREAM or FRAME)
70 * @channels: Channel resources used by the client
71 * @num_channels: Number of channel resources
72 * @num_hw_channels: Number of channels the transceiver is configured for [1..16]
73 * @speed: Max bit transmission speed (Kbit/s)
74 * @flow: RX flow type (SYNCHRONIZED or PIPELINE)
75 * @arb_mode: Arbitration mode for TX frame (Round robin, priority)
76 */
77 struct hsi_config {
78 unsigned int mode;
79 struct hsi_channel *channels;
80 unsigned int num_channels;
81 unsigned int num_hw_channels;
82 unsigned int speed;
83 union {
84 unsigned int flow; /* RX only */
85 unsigned int arb_mode; /* TX only */
86 };
87 };
88
89 /**
90 * struct hsi_board_info - HSI client board info
91 * @name: Name for the HSI device
92 * @hsi_id: HSI controller id where the client sits
93 * @port: Port number in the controller where the client sits
94 * @tx_cfg: HSI TX configuration
95 * @rx_cfg: HSI RX configuration
96 * @platform_data: Platform related data
97 * @archdata: Architecture-dependent device data
98 */
99 struct hsi_board_info {
100 const char *name;
101 unsigned int hsi_id;
102 unsigned int port;
103 struct hsi_config tx_cfg;
104 struct hsi_config rx_cfg;
105 void *platform_data;
106 struct dev_archdata *archdata;
107 };
108
109 #ifdef CONFIG_HSI_BOARDINFO
110 extern int hsi_register_board_info(struct hsi_board_info const *info,
111 unsigned int len);
112 #else
113 static inline int hsi_register_board_info(struct hsi_board_info const *info,
114 unsigned int len)
115 {
116 return 0;
117 }
118 #endif /* CONFIG_HSI_BOARDINFO */
119
120 /**
121 * struct hsi_client - HSI client attached to an HSI port
122 * @device: Driver model representation of the device
123 * @tx_cfg: HSI TX configuration
124 * @rx_cfg: HSI RX configuration
125 */
126 struct hsi_client {
127 struct device device;
128 struct hsi_config tx_cfg;
129 struct hsi_config rx_cfg;
130 /* private: */
131 void (*ehandler)(struct hsi_client *, unsigned long);
132 unsigned int pclaimed:1;
133 struct notifier_block nb;
134 };
135
136 #define to_hsi_client(dev) container_of(dev, struct hsi_client, device)
137
138 static inline void hsi_client_set_drvdata(struct hsi_client *cl, void *data)
139 {
140 dev_set_drvdata(&cl->device, data);
141 }
142
143 static inline void *hsi_client_drvdata(struct hsi_client *cl)
144 {
145 return dev_get_drvdata(&cl->device);
146 }
147
148 int hsi_register_port_event(struct hsi_client *cl,
149 void (*handler)(struct hsi_client *, unsigned long));
150 int hsi_unregister_port_event(struct hsi_client *cl);
151
152 /**
153 * struct hsi_client_driver - Driver associated to an HSI client
154 * @driver: Driver model representation of the driver
155 */
156 struct hsi_client_driver {
157 struct device_driver driver;
158 };
159
160 #define to_hsi_client_driver(drv) container_of(drv, struct hsi_client_driver,\
161 driver)
162
163 int hsi_register_client_driver(struct hsi_client_driver *drv);
164
165 static inline void hsi_unregister_client_driver(struct hsi_client_driver *drv)
166 {
167 driver_unregister(&drv->driver);
168 }
169
170 /**
171 * struct hsi_msg - HSI message descriptor
172 * @link: Free to use by the current descriptor owner
173 * @cl: HSI device client that issues the transfer
174 * @sgt: Head of the scatterlist array
175 * @context: Client context data associated to the transfer
176 * @complete: Transfer completion callback
177 * @destructor: Destructor to free resources when flushing
178 * @status: Status of the transfer when completed
179 * @actual_len: Actual length of data transferred on completion
180 * @channel: Channel were to TX/RX the message
181 * @ttype: Transfer type (TX if set, RX otherwise)
182 * @break_frame: if true HSI will send/receive a break frame. Data buffers are
183 * ignored in the request.
184 */
185 struct hsi_msg {
186 struct list_head link;
187 struct hsi_client *cl;
188 struct sg_table sgt;
189 void *context;
190
191 void (*complete)(struct hsi_msg *msg);
192 void (*destructor)(struct hsi_msg *msg);
193
194 int status;
195 unsigned int actual_len;
196 unsigned int channel;
197 unsigned int ttype:1;
198 unsigned int break_frame:1;
199 };
200
201 struct hsi_msg *hsi_alloc_msg(unsigned int n_frag, gfp_t flags);
202 void hsi_free_msg(struct hsi_msg *msg);
203
204 /**
205 * struct hsi_port - HSI port device
206 * @device: Driver model representation of the device
207 * @tx_cfg: Current TX path configuration
208 * @rx_cfg: Current RX path configuration
209 * @num: Port number
210 * @shared: Set when port can be shared by different clients
211 * @claimed: Reference count of clients which claimed the port
212 * @lock: Serialize port claim
213 * @async: Asynchronous transfer callback
214 * @setup: Callback to set the HSI client configuration
215 * @flush: Callback to clean the HW state and destroy all pending transfers
216 * @start_tx: Callback to inform that a client wants to TX data
217 * @stop_tx: Callback to inform that a client no longer wishes to TX data
218 * @release: Callback to inform that a client no longer uses the port
219 * @n_head: Notifier chain for signaling port events to the clients.
220 */
221 struct hsi_port {
222 struct device device;
223 struct hsi_config tx_cfg;
224 struct hsi_config rx_cfg;
225 unsigned int num;
226 unsigned int shared:1;
227 int claimed;
228 struct mutex lock;
229 int (*async)(struct hsi_msg *msg);
230 int (*setup)(struct hsi_client *cl);
231 int (*flush)(struct hsi_client *cl);
232 int (*start_tx)(struct hsi_client *cl);
233 int (*stop_tx)(struct hsi_client *cl);
234 int (*release)(struct hsi_client *cl);
235 /* private */
236 struct blocking_notifier_head n_head;
237 };
238
239 #define to_hsi_port(dev) container_of(dev, struct hsi_port, device)
240 #define hsi_get_port(cl) to_hsi_port((cl)->device.parent)
241
242 int hsi_event(struct hsi_port *port, unsigned long event);
243 int hsi_claim_port(struct hsi_client *cl, unsigned int share);
244 void hsi_release_port(struct hsi_client *cl);
245
246 static inline int hsi_port_claimed(struct hsi_client *cl)
247 {
248 return cl->pclaimed;
249 }
250
251 static inline void hsi_port_set_drvdata(struct hsi_port *port, void *data)
252 {
253 dev_set_drvdata(&port->device, data);
254 }
255
256 static inline void *hsi_port_drvdata(struct hsi_port *port)
257 {
258 return dev_get_drvdata(&port->device);
259 }
260
261 /**
262 * struct hsi_controller - HSI controller device
263 * @device: Driver model representation of the device
264 * @owner: Pointer to the module owning the controller
265 * @id: HSI controller ID
266 * @num_ports: Number of ports in the HSI controller
267 * @port: Array of HSI ports
268 */
269 struct hsi_controller {
270 struct device device;
271 struct module *owner;
272 unsigned int id;
273 unsigned int num_ports;
274 struct hsi_port **port;
275 };
276
277 #define to_hsi_controller(dev) container_of(dev, struct hsi_controller, device)
278
279 struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags);
280 void hsi_put_controller(struct hsi_controller *hsi);
281 int hsi_register_controller(struct hsi_controller *hsi);
282 void hsi_unregister_controller(struct hsi_controller *hsi);
283 struct hsi_client *hsi_new_client(struct hsi_port *port,
284 struct hsi_board_info *info);
285 int hsi_remove_client(struct device *dev, void *data);
286 void hsi_port_unregister_clients(struct hsi_port *port);
287
288 #ifdef CONFIG_OF
289 void hsi_add_clients_from_dt(struct hsi_port *port,
290 struct device_node *clients);
291 #else
292 static inline void hsi_add_clients_from_dt(struct hsi_port *port,
293 struct device_node *clients)
294 {
295 return;
296 }
297 #endif
298
299 static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi,
300 void *data)
301 {
302 dev_set_drvdata(&hsi->device, data);
303 }
304
305 static inline void *hsi_controller_drvdata(struct hsi_controller *hsi)
306 {
307 return dev_get_drvdata(&hsi->device);
308 }
309
310 static inline struct hsi_port *hsi_find_port_num(struct hsi_controller *hsi,
311 unsigned int num)
312 {
313 return (num < hsi->num_ports) ? hsi->port[num] : NULL;
314 }
315
316 /*
317 * API for HSI clients
318 */
319 int hsi_async(struct hsi_client *cl, struct hsi_msg *msg);
320
321 int hsi_get_channel_id_by_name(struct hsi_client *cl, char *name);
322
323 /**
324 * hsi_id - Get HSI controller ID associated to a client
325 * @cl: Pointer to a HSI client
326 *
327 * Return the controller id where the client is attached to
328 */
329 static inline unsigned int hsi_id(struct hsi_client *cl)
330 {
331 return to_hsi_controller(cl->device.parent->parent)->id;
332 }
333
334 /**
335 * hsi_port_id - Gets the port number a client is attached to
336 * @cl: Pointer to HSI client
337 *
338 * Return the port number associated to the client
339 */
340 static inline unsigned int hsi_port_id(struct hsi_client *cl)
341 {
342 return to_hsi_port(cl->device.parent)->num;
343 }
344
345 /**
346 * hsi_setup - Configure the client's port
347 * @cl: Pointer to the HSI client
348 *
349 * When sharing ports, clients should either relay on a single
350 * client setup or have the same setup for all of them.
351 *
352 * Return -errno on failure, 0 on success
353 */
354 static inline int hsi_setup(struct hsi_client *cl)
355 {
356 if (!hsi_port_claimed(cl))
357 return -EACCES;
358 return hsi_get_port(cl)->setup(cl);
359 }
360
361 /**
362 * hsi_flush - Flush all pending transactions on the client's port
363 * @cl: Pointer to the HSI client
364 *
365 * This function will destroy all pending hsi_msg in the port and reset
366 * the HW port so it is ready to receive and transmit from a clean state.
367 *
368 * Return -errno on failure, 0 on success
369 */
370 static inline int hsi_flush(struct hsi_client *cl)
371 {
372 if (!hsi_port_claimed(cl))
373 return -EACCES;
374 return hsi_get_port(cl)->flush(cl);
375 }
376
377 /**
378 * hsi_async_read - Submit a read transfer
379 * @cl: Pointer to the HSI client
380 * @msg: HSI message descriptor of the transfer
381 *
382 * Return -errno on failure, 0 on success
383 */
384 static inline int hsi_async_read(struct hsi_client *cl, struct hsi_msg *msg)
385 {
386 msg->ttype = HSI_MSG_READ;
387 return hsi_async(cl, msg);
388 }
389
390 /**
391 * hsi_async_write - Submit a write transfer
392 * @cl: Pointer to the HSI client
393 * @msg: HSI message descriptor of the transfer
394 *
395 * Return -errno on failure, 0 on success
396 */
397 static inline int hsi_async_write(struct hsi_client *cl, struct hsi_msg *msg)
398 {
399 msg->ttype = HSI_MSG_WRITE;
400 return hsi_async(cl, msg);
401 }
402
403 /**
404 * hsi_start_tx - Signal the port that the client wants to start a TX
405 * @cl: Pointer to the HSI client
406 *
407 * Return -errno on failure, 0 on success
408 */
409 static inline int hsi_start_tx(struct hsi_client *cl)
410 {
411 if (!hsi_port_claimed(cl))
412 return -EACCES;
413 return hsi_get_port(cl)->start_tx(cl);
414 }
415
416 /**
417 * hsi_stop_tx - Signal the port that the client no longer wants to transmit
418 * @cl: Pointer to the HSI client
419 *
420 * Return -errno on failure, 0 on success
421 */
422 static inline int hsi_stop_tx(struct hsi_client *cl)
423 {
424 if (!hsi_port_claimed(cl))
425 return -EACCES;
426 return hsi_get_port(cl)->stop_tx(cl);
427 }
428 #endif /* __LINUX_HSI_H__ */
429
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