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 */
38enum {
39	HSI_MODE_STREAM	= 1,
40	HSI_MODE_FRAME,
41};
42
43enum {
44	HSI_FLOW_SYNC,	/* Synchronized flow */
45	HSI_FLOW_PIPE,	/* Pipelined flow */
46};
47
48enum {
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 */
56enum {
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 */
65enum {
66	HSI_EVENT_START_RX,
67	HSI_EVENT_STOP_RX,
68};
69
70/**
71 * struct hsi_channel - channel resource used by the hsi clients
72 * @id: Channel number
73 * @name: Channel name
74 */
75struct hsi_channel {
76	unsigned int	id;
77	const char	*name;
78};
79
80/**
81 * struct hsi_config - Configuration for RX/TX HSI modules
82 * @mode: Bit transmission mode (STREAM or FRAME)
83 * @channels: Channel resources used by the client
84 * @num_channels: Number of channel resources
85 * @num_hw_channels: Number of channels the transceiver is configured for [1..16]
86 * @speed: Max bit transmission speed (Kbit/s)
87 * @flow: RX flow type (SYNCHRONIZED or PIPELINE)
88 * @arb_mode: Arbitration mode for TX frame (Round robin, priority)
89 */
90struct hsi_config {
91	unsigned int		mode;
92	struct hsi_channel	*channels;
93	unsigned int		num_channels;
94	unsigned int		num_hw_channels;
95	unsigned int		speed;
96	union {
97		unsigned int	flow;		/* RX only */
98		unsigned int	arb_mode;	/* TX only */
99	};
100};
101
102/**
103 * struct hsi_board_info - HSI client board info
104 * @name: Name for the HSI device
105 * @hsi_id: HSI controller id where the client sits
106 * @port: Port number in the controller where the client sits
107 * @tx_cfg: HSI TX configuration
108 * @rx_cfg: HSI RX configuration
109 * @platform_data: Platform related data
110 * @archdata: Architecture-dependent device data
111 */
112struct hsi_board_info {
113	const char		*name;
114	unsigned int		hsi_id;
115	unsigned int		port;
116	struct hsi_config	tx_cfg;
117	struct hsi_config	rx_cfg;
118	void			*platform_data;
119	struct dev_archdata	*archdata;
120};
121
122#ifdef CONFIG_HSI_BOARDINFO
123extern int hsi_register_board_info(struct hsi_board_info const *info,
124							unsigned int len);
125#else
126static inline int hsi_register_board_info(struct hsi_board_info const *info,
127							unsigned int len)
128{
129	return 0;
130}
131#endif /* CONFIG_HSI_BOARDINFO */
132
133/**
134 * struct hsi_client - HSI client attached to an HSI port
135 * @device: Driver model representation of the device
136 * @tx_cfg: HSI TX configuration
137 * @rx_cfg: HSI RX configuration
138 * @e_handler: Callback for handling port events (RX Wake High/Low)
139 * @pclaimed: Keeps tracks if the clients claimed its associated HSI port
140 * @nb: Notifier block for port events
141 */
142struct hsi_client {
143	struct device		device;
144	struct hsi_config	tx_cfg;
145	struct hsi_config	rx_cfg;
146	/* private: */
147	void			(*ehandler)(struct hsi_client *, unsigned long);
148	unsigned int		pclaimed:1;
149	struct notifier_block	nb;
150};
151
152#define to_hsi_client(dev) container_of(dev, struct hsi_client, device)
153
154static inline void hsi_client_set_drvdata(struct hsi_client *cl, void *data)
155{
156	dev_set_drvdata(&cl->device, data);
157}
158
159static inline void *hsi_client_drvdata(struct hsi_client *cl)
160{
161	return dev_get_drvdata(&cl->device);
162}
163
164int hsi_register_port_event(struct hsi_client *cl,
165			void (*handler)(struct hsi_client *, unsigned long));
166int hsi_unregister_port_event(struct hsi_client *cl);
167
168/**
169 * struct hsi_client_driver - Driver associated to an HSI client
170 * @driver: Driver model representation of the driver
171 */
172struct hsi_client_driver {
173	struct device_driver	driver;
174};
175
176#define to_hsi_client_driver(drv) container_of(drv, struct hsi_client_driver,\
177									driver)
178
179int hsi_register_client_driver(struct hsi_client_driver *drv);
180
181static inline void hsi_unregister_client_driver(struct hsi_client_driver *drv)
182{
183	driver_unregister(&drv->driver);
184}
185
186/**
187 * struct hsi_msg - HSI message descriptor
188 * @link: Free to use by the current descriptor owner
189 * @cl: HSI device client that issues the transfer
190 * @sgt: Head of the scatterlist array
191 * @context: Client context data associated to the transfer
192 * @complete: Transfer completion callback
193 * @destructor: Destructor to free resources when flushing
194 * @status: Status of the transfer when completed
195 * @actual_len: Actual length of data transferred on completion
196 * @channel: Channel were to TX/RX the message
197 * @ttype: Transfer type (TX if set, RX otherwise)
198 * @break_frame: if true HSI will send/receive a break frame. Data buffers are
199 *		ignored in the request.
200 */
201struct hsi_msg {
202	struct list_head	link;
203	struct hsi_client	*cl;
204	struct sg_table		sgt;
205	void			*context;
206
207	void			(*complete)(struct hsi_msg *msg);
208	void			(*destructor)(struct hsi_msg *msg);
209
210	int			status;
211	unsigned int		actual_len;
212	unsigned int		channel;
213	unsigned int		ttype:1;
214	unsigned int		break_frame:1;
215};
216
217struct hsi_msg *hsi_alloc_msg(unsigned int n_frag, gfp_t flags);
218void hsi_free_msg(struct hsi_msg *msg);
219
220/**
221 * struct hsi_port - HSI port device
222 * @device: Driver model representation of the device
223 * @tx_cfg: Current TX path configuration
224 * @rx_cfg: Current RX path configuration
225 * @num: Port number
226 * @shared: Set when port can be shared by different clients
227 * @claimed: Reference count of clients which claimed the port
228 * @lock: Serialize port claim
229 * @async: Asynchronous transfer callback
230 * @setup: Callback to set the HSI client configuration
231 * @flush: Callback to clean the HW state and destroy all pending transfers
232 * @start_tx: Callback to inform that a client wants to TX data
233 * @stop_tx: Callback to inform that a client no longer wishes to TX data
234 * @release: Callback to inform that a client no longer uses the port
235 * @n_head: Notifier chain for signaling port events to the clients.
236 */
237struct hsi_port {
238	struct device			device;
239	struct hsi_config		tx_cfg;
240	struct hsi_config		rx_cfg;
241	unsigned int			num;
242	unsigned int			shared:1;
243	int				claimed;
244	struct mutex			lock;
245	int				(*async)(struct hsi_msg *msg);
246	int				(*setup)(struct hsi_client *cl);
247	int				(*flush)(struct hsi_client *cl);
248	int				(*start_tx)(struct hsi_client *cl);
249	int				(*stop_tx)(struct hsi_client *cl);
250	int				(*release)(struct hsi_client *cl);
251	/* private */
252	struct atomic_notifier_head	n_head;
253};
254
255#define to_hsi_port(dev) container_of(dev, struct hsi_port, device)
256#define hsi_get_port(cl) to_hsi_port((cl)->device.parent)
257
258int hsi_event(struct hsi_port *port, unsigned long event);
259int hsi_claim_port(struct hsi_client *cl, unsigned int share);
260void hsi_release_port(struct hsi_client *cl);
261
262static inline int hsi_port_claimed(struct hsi_client *cl)
263{
264	return cl->pclaimed;
265}
266
267static inline void hsi_port_set_drvdata(struct hsi_port *port, void *data)
268{
269	dev_set_drvdata(&port->device, data);
270}
271
272static inline void *hsi_port_drvdata(struct hsi_port *port)
273{
274	return dev_get_drvdata(&port->device);
275}
276
277/**
278 * struct hsi_controller - HSI controller device
279 * @device: Driver model representation of the device
280 * @owner: Pointer to the module owning the controller
281 * @id: HSI controller ID
282 * @num_ports: Number of ports in the HSI controller
283 * @port: Array of HSI ports
284 */
285struct hsi_controller {
286	struct device		device;
287	struct module		*owner;
288	unsigned int		id;
289	unsigned int		num_ports;
290	struct hsi_port		**port;
291};
292
293#define to_hsi_controller(dev) container_of(dev, struct hsi_controller, device)
294
295struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags);
296void hsi_put_controller(struct hsi_controller *hsi);
297int hsi_register_controller(struct hsi_controller *hsi);
298void hsi_unregister_controller(struct hsi_controller *hsi);
299struct hsi_client *hsi_new_client(struct hsi_port *port,
300						struct hsi_board_info *info);
301int hsi_remove_client(struct device *dev, void *data);
302void hsi_port_unregister_clients(struct hsi_port *port);
303
304#ifdef CONFIG_OF
305void hsi_add_clients_from_dt(struct hsi_port *port,
306			     struct device_node *clients);
307#else
308static inline void hsi_add_clients_from_dt(struct hsi_port *port,
309					   struct device_node *clients)
310{
311	return;
312}
313#endif
314
315static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi,
316								void *data)
317{
318	dev_set_drvdata(&hsi->device, data);
319}
320
321static inline void *hsi_controller_drvdata(struct hsi_controller *hsi)
322{
323	return dev_get_drvdata(&hsi->device);
324}
325
326static inline struct hsi_port *hsi_find_port_num(struct hsi_controller *hsi,
327							unsigned int num)
328{
329	return (num < hsi->num_ports) ? hsi->port[num] : NULL;
330}
331
332/*
333 * API for HSI clients
334 */
335int hsi_async(struct hsi_client *cl, struct hsi_msg *msg);
336
337int hsi_get_channel_id_by_name(struct hsi_client *cl, char *name);
338
339/**
340 * hsi_id - Get HSI controller ID associated to a client
341 * @cl: Pointer to a HSI client
342 *
343 * Return the controller id where the client is attached to
344 */
345static inline unsigned int hsi_id(struct hsi_client *cl)
346{
347	return	to_hsi_controller(cl->device.parent->parent)->id;
348}
349
350/**
351 * hsi_port_id - Gets the port number a client is attached to
352 * @cl: Pointer to HSI client
353 *
354 * Return the port number associated to the client
355 */
356static inline unsigned int hsi_port_id(struct hsi_client *cl)
357{
358	return	to_hsi_port(cl->device.parent)->num;
359}
360
361/**
362 * hsi_setup - Configure the client's port
363 * @cl: Pointer to the HSI client
364 *
365 * When sharing ports, clients should either relay on a single
366 * client setup or have the same setup for all of them.
367 *
368 * Return -errno on failure, 0 on success
369 */
370static inline int hsi_setup(struct hsi_client *cl)
371{
372	if (!hsi_port_claimed(cl))
373		return -EACCES;
374	return	hsi_get_port(cl)->setup(cl);
375}
376
377/**
378 * hsi_flush - Flush all pending transactions on the client's port
379 * @cl: Pointer to the HSI client
380 *
381 * This function will destroy all pending hsi_msg in the port and reset
382 * the HW port so it is ready to receive and transmit from a clean state.
383 *
384 * Return -errno on failure, 0 on success
385 */
386static inline int hsi_flush(struct hsi_client *cl)
387{
388	if (!hsi_port_claimed(cl))
389		return -EACCES;
390	return hsi_get_port(cl)->flush(cl);
391}
392
393/**
394 * hsi_async_read - Submit a read transfer
395 * @cl: Pointer to the HSI client
396 * @msg: HSI message descriptor of the transfer
397 *
398 * Return -errno on failure, 0 on success
399 */
400static inline int hsi_async_read(struct hsi_client *cl, struct hsi_msg *msg)
401{
402	msg->ttype = HSI_MSG_READ;
403	return hsi_async(cl, msg);
404}
405
406/**
407 * hsi_async_write - Submit a write transfer
408 * @cl: Pointer to the HSI client
409 * @msg: HSI message descriptor of the transfer
410 *
411 * Return -errno on failure, 0 on success
412 */
413static inline int hsi_async_write(struct hsi_client *cl, struct hsi_msg *msg)
414{
415	msg->ttype = HSI_MSG_WRITE;
416	return hsi_async(cl, msg);
417}
418
419/**
420 * hsi_start_tx - Signal the port that the client wants to start a TX
421 * @cl: Pointer to the HSI client
422 *
423 * Return -errno on failure, 0 on success
424 */
425static inline int hsi_start_tx(struct hsi_client *cl)
426{
427	if (!hsi_port_claimed(cl))
428		return -EACCES;
429	return hsi_get_port(cl)->start_tx(cl);
430}
431
432/**
433 * hsi_stop_tx - Signal the port that the client no longer wants to transmit
434 * @cl: Pointer to the HSI client
435 *
436 * Return -errno on failure, 0 on success
437 */
438static inline int hsi_stop_tx(struct hsi_client *cl)
439{
440	if (!hsi_port_claimed(cl))
441		return -EACCES;
442	return hsi_get_port(cl)->stop_tx(cl);
443}
444#endif /* __LINUX_HSI_H__ */
445