summaryrefslogtreecommitdiffstats
path: root/include/linux/serdev.h
blob: e69402d4a8aecbdc6fe4a40e8ad7e01957badbd6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
/*
 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
#ifndef _LINUX_SERDEV_H
#define _LINUX_SERDEV_H

#include <linux/types.h>
#include <linux/device.h>
#include <linux/termios.h>
#include <linux/delay.h>

struct serdev_controller;
struct serdev_device;

/*
 * serdev device structures
 */

/**
 * struct serdev_device_ops - Callback operations for a serdev device
 * @receive_buf:	Function called with data received from device.
 * @write_wakeup:	Function called when ready to transmit more data.
 */
struct serdev_device_ops {
	int (*receive_buf)(struct serdev_device *, const unsigned char *, size_t);
	void (*write_wakeup)(struct serdev_device *);
};

/**
 * struct serdev_device - Basic representation of an serdev device
 * @dev:	Driver model representation of the device.
 * @nr:		Device number on serdev bus.
 * @ctrl:	serdev controller managing this device.
 * @ops:	Device operations.
 * @write_comp	Completion used by serdev_device_write() internally
 * @write_lock	Lock to serialize access when writing data
 */
struct serdev_device {
	struct device dev;
	int nr;
	struct serdev_controller *ctrl;
	const struct serdev_device_ops *ops;
	struct completion write_comp;
	struct mutex write_lock;
};

static inline struct serdev_device *to_serdev_device(struct device *d)
{
	return container_of(d, struct serdev_device, dev);
}

/**
 * struct serdev_device_driver - serdev slave device driver
 * @driver:	serdev device drivers should initialize name field of this
 *		structure.
 * @probe:	binds this driver to a serdev device.
 * @remove:	unbinds this driver from the serdev device.
 */
struct serdev_device_driver {
	struct device_driver driver;
	int	(*probe)(struct serdev_device *);
	void	(*remove)(struct serdev_device *);
};

static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d)
{
	return container_of(d, struct serdev_device_driver, driver);
}

/*
 * serdev controller structures
 */
struct serdev_controller_ops {
	int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t);
	void (*write_flush)(struct serdev_controller *);
	int (*write_room)(struct serdev_controller *);
	int (*open)(struct serdev_controller *);
	void (*close)(struct serdev_controller *);
	void (*set_flow_control)(struct serdev_controller *, bool);
	unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
	void (*wait_until_sent)(struct serdev_controller *, long);
	int (*get_tiocm)(struct serdev_controller *);
	int (*set_tiocm)(struct serdev_controller *, unsigned int, unsigned int);
};

/**
 * struct serdev_controller - interface to the serdev controller
 * @dev:	Driver model representation of the device.
 * @nr:		number identifier for this controller/bus.
 * @serdev:	Pointer to slave device for this controller.
 * @ops:	Controller operations.
 */
struct serdev_controller {
	struct device		dev;
	unsigned int		nr;
	struct serdev_device	*serdev;
	const struct serdev_controller_ops *ops;
};

static inline struct serdev_controller *to_serdev_controller(struct device *d)
{
	return container_of(d, struct serdev_controller, dev);
}

static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev)
{
	return dev_get_drvdata(&serdev->dev);
}

static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data)
{
	dev_set_drvdata(&serdev->dev, data);
}

/**
 * serdev_device_put() - decrement serdev device refcount
 * @serdev	serdev device.
 */
static inline void serdev_device_put(struct serdev_device *serdev)
{
	if (serdev)
		put_device(&serdev->dev);
}

static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
					      const struct serdev_device_ops *ops)
{
	serdev->ops = ops;
}

static inline
void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl)
{
	return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
}

static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
					       void *data)
{
	dev_set_drvdata(&ctrl->dev, data);
}

/**
 * serdev_controller_put() - decrement controller refcount
 * @ctrl	serdev controller.
 */
static inline void serdev_controller_put(struct serdev_controller *ctrl)
{
	if (ctrl)
		put_device(&ctrl->dev);
}

struct serdev_device *serdev_device_alloc(struct serdev_controller *);
int serdev_device_add(struct serdev_device *);
void serdev_device_remove(struct serdev_device *);

struct serdev_controller *serdev_controller_alloc(struct device *, size_t);
int serdev_controller_add(struct serdev_controller *);
void serdev_controller_remove(struct serdev_controller *);

static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
{
	struct serdev_device *serdev = ctrl->serdev;

	if (!serdev || !serdev->ops->write_wakeup)
		return;

	serdev->ops->write_wakeup(serdev);
}

static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl,
					      const unsigned char *data,
					      size_t count)
{
	struct serdev_device *serdev = ctrl->serdev;

	if (!serdev || !serdev->ops->receive_buf)
		return -EINVAL;

	return serdev->ops->receive_buf(serdev, data, count);
}

#if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)

int serdev_device_open(struct serdev_device *);
void serdev_device_close(struct serdev_device *);
unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
void serdev_device_set_flow_control(struct serdev_device *, bool);
int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t);
void serdev_device_wait_until_sent(struct serdev_device *, long);
int serdev_device_get_tiocm(struct serdev_device *);
int serdev_device_set_tiocm(struct serdev_device *, int, int);
void serdev_device_write_wakeup(struct serdev_device *);
int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, unsigned long);
void serdev_device_write_flush(struct serdev_device *);
int serdev_device_write_room(struct serdev_device *);

/*
 * serdev device driver functions
 */
int __serdev_device_driver_register(struct serdev_device_driver *, struct module *);
#define serdev_device_driver_register(sdrv) \
	__serdev_device_driver_register(sdrv, THIS_MODULE)

/**
 * serdev_device_driver_unregister() - unregister an serdev client driver
 * @sdrv:	the driver to unregister
 */
static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
{
	if (sdrv)
		driver_unregister(&sdrv->driver);
}

#define module_serdev_device_driver(__serdev_device_driver) \
	module_driver(__serdev_device_driver, serdev_device_driver_register, \
			serdev_device_driver_unregister)

#else

static inline int serdev_device_open(struct serdev_device *sdev)
{
	return -ENODEV;
}
static inline void serdev_device_close(struct serdev_device *sdev) {}
static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
{
	return 0;
}
static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
static inline int serdev_device_write_buf(struct serdev_device *serdev,
					  const unsigned char *buf,
					  size_t count)
{
	return -ENODEV;
}
static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
static inline int serdev_device_get_tiocm(struct serdev_device *serdev)
{
	return -ENOTSUPP;
}
static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
{
	return -ENOTSUPP;
}
static inline int serdev_device_write(struct serdev_device *sdev, const unsigned char *buf,
				      size_t count, unsigned long timeout)
{
	return -ENODEV;
}
static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
static inline int serdev_device_write_room(struct serdev_device *sdev)
{
	return 0;
}

#define serdev_device_driver_register(x)
#define serdev_device_driver_unregister(x)

#endif /* CONFIG_SERIAL_DEV_BUS */

static inline bool serdev_device_get_cts(struct serdev_device *serdev)
{
	int status = serdev_device_get_tiocm(serdev);
	return !!(status & TIOCM_CTS);
}

static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
{
	unsigned long timeout;
	bool signal;

	timeout = jiffies + msecs_to_jiffies(timeout_ms);
	while (time_is_after_jiffies(timeout)) {
		signal = serdev_device_get_cts(serdev);
		if (signal == state)
			return 0;
		usleep_range(1000, 2000);
	}

	return -ETIMEDOUT;
}

static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
{
	if (enable)
		return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
	else
		return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
}

/*
 * serdev hooks into TTY core
 */
struct tty_port;
struct tty_driver;

#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
struct device *serdev_tty_port_register(struct tty_port *port,
					struct device *parent,
					struct tty_driver *drv, int idx);
int serdev_tty_port_unregister(struct tty_port *port);
#else
static inline struct device *serdev_tty_port_register(struct tty_port *port,
					   struct device *parent,
					   struct tty_driver *drv, int idx)
{
	return ERR_PTR(-ENODEV);
}
static inline int serdev_tty_port_unregister(struct tty_port *port)
{
	return -ENODEV;
}
#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */

#endif /*_LINUX_SERDEV_H */