1 /*
2 * HSI core header file.
3 *
4 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
5 *
6 * Contact: Carlos Chinea <carlos.chinea@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23 #ifndef __LINUX_HSI_H__
24 #define __LINUX_HSI_H__
25
26 #include <linux/device.h>
27 #include <linux/mutex.h>
28 #include <linux/scatterlist.h>
29 #include <linux/list.h>
30 #include <linux/module.h>
31 #include <linux/notifier.h>
32
33 /* HSI message ttype */
34 #define HSI_MSG_READ 0
35 #define HSI_MSG_WRITE 1
36
37 /* HSI configuration values */
38 enum {
39 HSI_MODE_STREAM = 1,
40 HSI_MODE_FRAME,
41 };
42
43 enum {
44 HSI_FLOW_SYNC, /* Synchronized flow */
45 HSI_FLOW_PIPE, /* Pipelined flow */
46 };
47
48 enum {
49 HSI_ARB_RR, /* Round-robin arbitration */
50 HSI_ARB_PRIO, /* Channel priority arbitration */
51 };
52
53 #define HSI_MAX_CHANNELS 16
54
55 /* HSI message status codes */
56 enum {
57 HSI_STATUS_COMPLETED, /* Message transfer is completed */
58 HSI_STATUS_PENDING, /* Message pending to be read/write (POLL) */
59 HSI_STATUS_PROCEEDING, /* Message transfer is ongoing */
60 HSI_STATUS_QUEUED, /* Message waiting to be served */
61 HSI_STATUS_ERROR, /* Error when message transfer was ongoing */
62 };
63
64 /* HSI port event codes */
65 enum {
66 HSI_EVENT_START_RX,
67 HSI_EVENT_STOP_RX,
68 };
69
70 /**
71 * struct hsi_config - Configuration for RX/TX HSI modules
72 * @mode: Bit transmission mode (STREAM or FRAME)
73 * @channels: Number of channels to use [1..16]
74 * @speed: Max bit transmission speed (Kbit/s)
75 * @flow: RX flow type (SYNCHRONIZED or PIPELINE)
76 * @arb_mode: Arbitration mode for TX frame (Round robin, priority)
77 */
78 struct hsi_config {
79 unsigned int mode;
80 unsigned int channels;
81 unsigned int speed;
82 union {
83 unsigned int flow; /* RX only */
84 unsigned int arb_mode; /* TX only */
85 };
86 };
87
88 /**
89 * struct hsi_board_info - HSI client board info
90 * @name: Name for the HSI device
91 * @hsi_id: HSI controller id where the client sits
92 * @port: Port number in the controller where the client sits
93 * @tx_cfg: HSI TX configuration
94 * @rx_cfg: HSI RX configuration
95 * @platform_data: Platform related data
96 * @archdata: Architecture-dependent device data
97 */
98 struct hsi_board_info {
99 const char *name;
100 unsigned int hsi_id;
101 unsigned int port;
102 struct hsi_config tx_cfg;
103 struct hsi_config rx_cfg;
104 void *platform_data;
105 struct dev_archdata *archdata;
106 };
107
108 #ifdef CONFIG_HSI_BOARDINFO
109 extern int hsi_register_board_info(struct hsi_board_info const *info,
110 unsigned int len);
111 #else
hsi_register_board_info(struct hsi_board_info const * info,unsigned int len)112 static inline int hsi_register_board_info(struct hsi_board_info const *info,
113 unsigned int len)
114 {
115 return 0;
116 }
117 #endif /* CONFIG_HSI_BOARDINFO */
118
119 /**
120 * struct hsi_client - HSI client attached to an HSI port
121 * @device: Driver model representation of the device
122 * @tx_cfg: HSI TX configuration
123 * @rx_cfg: HSI RX configuration
124 * e_handler: Callback for handling port events (RX Wake High/Low)
125 * pclaimed: Keeps tracks if the clients claimed its associated HSI port
126 * nb: Notifier block for port events
127 */
128 struct hsi_client {
129 struct device device;
130 struct hsi_config tx_cfg;
131 struct hsi_config rx_cfg;
132 /* private: */
133 void (*ehandler)(struct hsi_client *, unsigned long);
134 unsigned int pclaimed:1;
135 struct notifier_block nb;
136 };
137
138 #define to_hsi_client(dev) container_of(dev, struct hsi_client, device)
139
hsi_client_set_drvdata(struct hsi_client * cl,void * data)140 static inline void hsi_client_set_drvdata(struct hsi_client *cl, void *data)
141 {
142 dev_set_drvdata(&cl->device, data);
143 }
144
hsi_client_drvdata(struct hsi_client * cl)145 static inline void *hsi_client_drvdata(struct hsi_client *cl)
146 {
147 return dev_get_drvdata(&cl->device);
148 }
149
150 int hsi_register_port_event(struct hsi_client *cl,
151 void (*handler)(struct hsi_client *, unsigned long));
152 int hsi_unregister_port_event(struct hsi_client *cl);
153
154 /**
155 * struct hsi_client_driver - Driver associated to an HSI client
156 * @driver: Driver model representation of the driver
157 */
158 struct hsi_client_driver {
159 struct device_driver driver;
160 };
161
162 #define to_hsi_client_driver(drv) container_of(drv, struct hsi_client_driver,\
163 driver)
164
165 int hsi_register_client_driver(struct hsi_client_driver *drv);
166
hsi_unregister_client_driver(struct hsi_client_driver * drv)167 static inline void hsi_unregister_client_driver(struct hsi_client_driver *drv)
168 {
169 driver_unregister(&drv->driver);
170 }
171
172 /**
173 * struct hsi_msg - HSI message descriptor
174 * @link: Free to use by the current descriptor owner
175 * @cl: HSI device client that issues the transfer
176 * @sgt: Head of the scatterlist array
177 * @context: Client context data associated to the transfer
178 * @complete: Transfer completion callback
179 * @destructor: Destructor to free resources when flushing
180 * @status: Status of the transfer when completed
181 * @actual_len: Actual length of data transfered on completion
182 * @channel: Channel were to TX/RX the message
183 * @ttype: Transfer type (TX if set, RX otherwise)
184 * @break_frame: if true HSI will send/receive a break frame. Data buffers are
185 * ignored in the request.
186 */
187 struct hsi_msg {
188 struct list_head link;
189 struct hsi_client *cl;
190 struct sg_table sgt;
191 void *context;
192
193 void (*complete)(struct hsi_msg *msg);
194 void (*destructor)(struct hsi_msg *msg);
195
196 int status;
197 unsigned int actual_len;
198 unsigned int channel;
199 unsigned int ttype:1;
200 unsigned int break_frame:1;
201 };
202
203 struct hsi_msg *hsi_alloc_msg(unsigned int n_frag, gfp_t flags);
204 void hsi_free_msg(struct hsi_msg *msg);
205
206 /**
207 * struct hsi_port - HSI port device
208 * @device: Driver model representation of the device
209 * @tx_cfg: Current TX path configuration
210 * @rx_cfg: Current RX path configuration
211 * @num: Port number
212 * @shared: Set when port can be shared by different clients
213 * @claimed: Reference count of clients which claimed the port
214 * @lock: Serialize port claim
215 * @async: Asynchronous transfer callback
216 * @setup: Callback to set the HSI client configuration
217 * @flush: Callback to clean the HW state and destroy all pending transfers
218 * @start_tx: Callback to inform that a client wants to TX data
219 * @stop_tx: Callback to inform that a client no longer wishes to TX data
220 * @release: Callback to inform that a client no longer uses the port
221 * @n_head: Notifier chain for signaling port events to the clients.
222 */
223 struct hsi_port {
224 struct device device;
225 struct hsi_config tx_cfg;
226 struct hsi_config rx_cfg;
227 unsigned int num;
228 unsigned int shared:1;
229 int claimed;
230 struct mutex lock;
231 int (*async)(struct hsi_msg *msg);
232 int (*setup)(struct hsi_client *cl);
233 int (*flush)(struct hsi_client *cl);
234 int (*start_tx)(struct hsi_client *cl);
235 int (*stop_tx)(struct hsi_client *cl);
236 int (*release)(struct hsi_client *cl);
237 /* private */
238 struct atomic_notifier_head n_head;
239 };
240
241 #define to_hsi_port(dev) container_of(dev, struct hsi_port, device)
242 #define hsi_get_port(cl) to_hsi_port((cl)->device.parent)
243
244 int hsi_event(struct hsi_port *port, unsigned long event);
245 int hsi_claim_port(struct hsi_client *cl, unsigned int share);
246 void hsi_release_port(struct hsi_client *cl);
247
hsi_port_claimed(struct hsi_client * cl)248 static inline int hsi_port_claimed(struct hsi_client *cl)
249 {
250 return cl->pclaimed;
251 }
252
hsi_port_set_drvdata(struct hsi_port * port,void * data)253 static inline void hsi_port_set_drvdata(struct hsi_port *port, void *data)
254 {
255 dev_set_drvdata(&port->device, data);
256 }
257
hsi_port_drvdata(struct hsi_port * port)258 static inline void *hsi_port_drvdata(struct hsi_port *port)
259 {
260 return dev_get_drvdata(&port->device);
261 }
262
263 /**
264 * struct hsi_controller - HSI controller device
265 * @device: Driver model representation of the device
266 * @owner: Pointer to the module owning the controller
267 * @id: HSI controller ID
268 * @num_ports: Number of ports in the HSI controller
269 * @port: Array of HSI ports
270 */
271 struct hsi_controller {
272 struct device device;
273 struct module *owner;
274 unsigned int id;
275 unsigned int num_ports;
276 struct hsi_port **port;
277 };
278
279 #define to_hsi_controller(dev) container_of(dev, struct hsi_controller, device)
280
281 struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags);
282 void hsi_put_controller(struct hsi_controller *hsi);
283 int hsi_register_controller(struct hsi_controller *hsi);
284 void hsi_unregister_controller(struct hsi_controller *hsi);
285
hsi_controller_set_drvdata(struct hsi_controller * hsi,void * data)286 static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi,
287 void *data)
288 {
289 dev_set_drvdata(&hsi->device, data);
290 }
291
hsi_controller_drvdata(struct hsi_controller * hsi)292 static inline void *hsi_controller_drvdata(struct hsi_controller *hsi)
293 {
294 return dev_get_drvdata(&hsi->device);
295 }
296
hsi_find_port_num(struct hsi_controller * hsi,unsigned int num)297 static inline struct hsi_port *hsi_find_port_num(struct hsi_controller *hsi,
298 unsigned int num)
299 {
300 return (num < hsi->num_ports) ? hsi->port[num] : NULL;
301 }
302
303 /*
304 * API for HSI clients
305 */
306 int hsi_async(struct hsi_client *cl, struct hsi_msg *msg);
307
308 /**
309 * hsi_id - Get HSI controller ID associated to a client
310 * @cl: Pointer to a HSI client
311 *
312 * Return the controller id where the client is attached to
313 */
hsi_id(struct hsi_client * cl)314 static inline unsigned int hsi_id(struct hsi_client *cl)
315 {
316 return to_hsi_controller(cl->device.parent->parent)->id;
317 }
318
319 /**
320 * hsi_port_id - Gets the port number a client is attached to
321 * @cl: Pointer to HSI client
322 *
323 * Return the port number associated to the client
324 */
hsi_port_id(struct hsi_client * cl)325 static inline unsigned int hsi_port_id(struct hsi_client *cl)
326 {
327 return to_hsi_port(cl->device.parent)->num;
328 }
329
330 /**
331 * hsi_setup - Configure the client's port
332 * @cl: Pointer to the HSI client
333 *
334 * When sharing ports, clients should either relay on a single
335 * client setup or have the same setup for all of them.
336 *
337 * Return -errno on failure, 0 on success
338 */
hsi_setup(struct hsi_client * cl)339 static inline int hsi_setup(struct hsi_client *cl)
340 {
341 if (!hsi_port_claimed(cl))
342 return -EACCES;
343 return hsi_get_port(cl)->setup(cl);
344 }
345
346 /**
347 * hsi_flush - Flush all pending transactions on the client's port
348 * @cl: Pointer to the HSI client
349 *
350 * This function will destroy all pending hsi_msg in the port and reset
351 * the HW port so it is ready to receive and transmit from a clean state.
352 *
353 * Return -errno on failure, 0 on success
354 */
hsi_flush(struct hsi_client * cl)355 static inline int hsi_flush(struct hsi_client *cl)
356 {
357 if (!hsi_port_claimed(cl))
358 return -EACCES;
359 return hsi_get_port(cl)->flush(cl);
360 }
361
362 /**
363 * hsi_async_read - Submit a read transfer
364 * @cl: Pointer to the HSI client
365 * @msg: HSI message descriptor of the transfer
366 *
367 * Return -errno on failure, 0 on success
368 */
hsi_async_read(struct hsi_client * cl,struct hsi_msg * msg)369 static inline int hsi_async_read(struct hsi_client *cl, struct hsi_msg *msg)
370 {
371 msg->ttype = HSI_MSG_READ;
372 return hsi_async(cl, msg);
373 }
374
375 /**
376 * hsi_async_write - Submit a write transfer
377 * @cl: Pointer to the HSI client
378 * @msg: HSI message descriptor of the transfer
379 *
380 * Return -errno on failure, 0 on success
381 */
hsi_async_write(struct hsi_client * cl,struct hsi_msg * msg)382 static inline int hsi_async_write(struct hsi_client *cl, struct hsi_msg *msg)
383 {
384 msg->ttype = HSI_MSG_WRITE;
385 return hsi_async(cl, msg);
386 }
387
388 /**
389 * hsi_start_tx - Signal the port that the client wants to start a TX
390 * @cl: Pointer to the HSI client
391 *
392 * Return -errno on failure, 0 on success
393 */
hsi_start_tx(struct hsi_client * cl)394 static inline int hsi_start_tx(struct hsi_client *cl)
395 {
396 if (!hsi_port_claimed(cl))
397 return -EACCES;
398 return hsi_get_port(cl)->start_tx(cl);
399 }
400
401 /**
402 * hsi_stop_tx - Signal the port that the client no longer wants to transmit
403 * @cl: Pointer to the HSI client
404 *
405 * Return -errno on failure, 0 on success
406 */
hsi_stop_tx(struct hsi_client * cl)407 static inline int hsi_stop_tx(struct hsi_client *cl)
408 {
409 if (!hsi_port_claimed(cl))
410 return -EACCES;
411 return hsi_get_port(cl)->stop_tx(cl);
412 }
413 #endif /* __LINUX_HSI_H__ */
414