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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
*/
#include <linux/kernel.h>
#include <linux/serdev.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/poll.h>
#define SERPORT_ACTIVE 1
struct serport {
struct tty_port *port;
struct tty_struct *tty;
struct tty_driver *tty_drv;
int tty_idx;
unsigned long flags;
};
/*
* Callback functions from the tty port.
*/
static int ttyport_receive_buf(struct tty_port *port, const unsigned char *cp,
const unsigned char *fp, size_t count)
{
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
int ret;
if (!test_bit(SERPORT_ACTIVE, &serport->flags))
return 0;
ret = serdev_controller_receive_buf(ctrl, cp, count);
dev_WARN_ONCE(&ctrl->dev, ret < 0 || ret > count,
"receive_buf returns %d (count = %zu)\n",
ret, count);
if (ret < 0)
return 0;
else if (ret > count)
return count;
return ret;
}
static void ttyport_write_wakeup(struct tty_port *port)
{
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty;
tty = tty_port_tty_get(port);
if (!tty)
return;
if (test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) &&
test_bit(SERPORT_ACTIVE, &serport->flags))
serdev_controller_write_wakeup(ctrl);
wake_up_interruptible_poll(&tty->write_wait, POLLOUT);
tty_kref_put(tty);
}
static const struct tty_port_client_operations client_ops = {
.receive_buf = ttyport_receive_buf,
.write_wakeup = ttyport_write_wakeup,
};
/*
* Callback functions from the serdev core.
*/
static int ttyport_write_buf(struct serdev_controller *ctrl, const unsigned char *data, size_t len)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
if (!test_bit(SERPORT_ACTIVE, &serport->flags))
return 0;
set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
return tty->ops->write(serport->tty, data, len);
}
static void ttyport_write_flush(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
tty_driver_flush_buffer(tty);
}
static int ttyport_write_room(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
return tty_write_room(tty);
}
static int ttyport_open(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty;
struct ktermios ktermios;
int ret;
tty = tty_init_dev(serport->tty_drv, serport->tty_idx);
if (IS_ERR(tty))
return PTR_ERR(tty);
serport->tty = tty;
if (!tty->ops->open || !tty->ops->close) {
ret = -ENODEV;
goto err_unlock;
}
ret = tty->ops->open(serport->tty, NULL);
if (ret)
goto err_close;
tty_unlock(serport->tty);
/* Bring the UART into a known 8 bits no parity hw fc state */
ktermios = tty->termios;
ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP |
INLCR | IGNCR | ICRNL | IXON);
ktermios.c_oflag &= ~OPOST;
ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
ktermios.c_cflag &= ~(CSIZE | PARENB);
ktermios.c_cflag |= CS8;
ktermios.c_cflag |= CRTSCTS;
/* Hangups are not supported so make sure to ignore carrier detect. */
ktermios.c_cflag |= CLOCAL;
tty_set_termios(tty, &ktermios);
set_bit(SERPORT_ACTIVE, &serport->flags);
return 0;
err_close:
tty->ops->close(tty, NULL);
err_unlock:
tty_unlock(tty);
tty_release_struct(tty, serport->tty_idx);
return ret;
}
static void ttyport_close(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
clear_bit(SERPORT_ACTIVE, &serport->flags);
tty_lock(tty);
if (tty->ops->close)
tty->ops->close(tty, NULL);
tty_unlock(tty);
tty_release_struct(tty, serport->tty_idx);
}
static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigned int speed)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
struct ktermios ktermios = tty->termios;
ktermios.c_cflag &= ~CBAUD;
tty_termios_encode_baud_rate(&ktermios, speed, speed);
/* tty_set_termios() return not checked as it is always 0 */
tty_set_termios(tty, &ktermios);
return ktermios.c_ospeed;
}
static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
struct ktermios ktermios = tty->termios;
if (enable)
ktermios.c_cflag |= CRTSCTS;
else
ktermios.c_cflag &= ~CRTSCTS;
tty_set_termios(tty, &ktermios);
}
static void ttyport_wait_until_sent(struct serdev_controller *ctrl, long timeout)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
tty_wait_until_sent(tty, timeout);
}
static int ttyport_get_tiocm(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
if (!tty->ops->tiocmget)
return -ENOTSUPP;
return tty->driver->ops->tiocmget(tty);
}
static int ttyport_set_tiocm(struct serdev_controller *ctrl, unsigned int set, unsigned int clear)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
if (!tty->ops->tiocmset)
return -ENOTSUPP;
return tty->driver->ops->tiocmset(tty, set, clear);
}
static const struct serdev_controller_ops ctrl_ops = {
.write_buf = ttyport_write_buf,
.write_flush = ttyport_write_flush,
.write_room = ttyport_write_room,
.open = ttyport_open,
.close = ttyport_close,
.set_flow_control = ttyport_set_flow_control,
.set_baudrate = ttyport_set_baudrate,
.wait_until_sent = ttyport_wait_until_sent,
.get_tiocm = ttyport_get_tiocm,
.set_tiocm = ttyport_set_tiocm,
};
struct device *serdev_tty_port_register(struct tty_port *port,
struct device *parent,
struct tty_driver *drv, int idx)
{
const struct tty_port_client_operations *old_ops;
struct serdev_controller *ctrl;
struct serport *serport;
int ret;
if (!port || !drv || !parent)
return ERR_PTR(-ENODEV);
ctrl = serdev_controller_alloc(parent, sizeof(struct serport));
if (!ctrl)
return ERR_PTR(-ENOMEM);
serport = serdev_controller_get_drvdata(ctrl);
serport->port = port;
serport->tty_idx = idx;
serport->tty_drv = drv;
ctrl->ops = &ctrl_ops;
old_ops = port->client_ops;
port->client_ops = &client_ops;
port->client_data = ctrl;
ret = serdev_controller_add(ctrl);
if (ret)
goto err_reset_data;
dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
return &ctrl->dev;
err_reset_data:
port->client_data = NULL;
port->client_ops = old_ops;
serdev_controller_put(ctrl);
return ERR_PTR(ret);
}
int serdev_tty_port_unregister(struct tty_port *port)
{
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
if (!serport)
return -ENODEV;
serdev_controller_remove(ctrl);
port->client_ops = NULL;
port->client_data = NULL;
serdev_controller_put(ctrl);
return 0;
}
|
