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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
4 */
5#include <linux/kernel.h>
6#include <linux/serdev.h>
7#include <linux/tty.h>
8#include <linux/tty_driver.h>
9#include <linux/poll.h>
10
11#define SERPORT_ACTIVE 1
12
13struct serport {
14 struct tty_port *port;
15 struct tty_struct *tty;
16 struct tty_driver *tty_drv;
17 int tty_idx;
18 unsigned long flags;
19};
20
21/*
22 * Callback functions from the tty port.
23 */
24
25static int ttyport_receive_buf(struct tty_port *port, const unsigned char *cp,
26 const unsigned char *fp, size_t count)
27{
28 struct serdev_controller *ctrl = port->client_data;
29 struct serport *serport = serdev_controller_get_drvdata(ctrl);
30 int ret;
31
32 if (!test_bit(SERPORT_ACTIVE, &serport->flags))
33 return 0;
34
35 ret = serdev_controller_receive_buf(ctrl, cp, count);
36
37 dev_WARN_ONCE(&ctrl->dev, ret < 0 || ret > count,
38 "receive_buf returns %d (count = %zu)\n",
39 ret, count);
40 if (ret < 0)
41 return 0;
42 else if (ret > count)
43 return count;
44
45 return ret;
46}
47
48static void ttyport_write_wakeup(struct tty_port *port)
49{
50 struct serdev_controller *ctrl = port->client_data;
51 struct serport *serport = serdev_controller_get_drvdata(ctrl);
52 struct tty_struct *tty;
53
54 tty = tty_port_tty_get(port);
55 if (!tty)
56 return;
57
58 if (test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) &&
59 test_bit(SERPORT_ACTIVE, &serport->flags))
60 serdev_controller_write_wakeup(ctrl);
61
62 /* Wake up any tty_wait_until_sent() */
63 wake_up_interruptible(&tty->write_wait);
64
65 tty_kref_put(tty);
66}
67
68static const struct tty_port_client_operations client_ops = {
69 .receive_buf = ttyport_receive_buf,
70 .write_wakeup = ttyport_write_wakeup,
71};
72
73/*
74 * Callback functions from the serdev core.
75 */
76
77static int ttyport_write_buf(struct serdev_controller *ctrl, const unsigned char *data, size_t len)
78{
79 struct serport *serport = serdev_controller_get_drvdata(ctrl);
80 struct tty_struct *tty = serport->tty;
81
82 if (!test_bit(SERPORT_ACTIVE, &serport->flags))
83 return 0;
84
85 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
86 return tty->ops->write(serport->tty, data, len);
87}
88
89static void ttyport_write_flush(struct serdev_controller *ctrl)
90{
91 struct serport *serport = serdev_controller_get_drvdata(ctrl);
92 struct tty_struct *tty = serport->tty;
93
94 tty_driver_flush_buffer(tty);
95}
96
97static int ttyport_write_room(struct serdev_controller *ctrl)
98{
99 struct serport *serport = serdev_controller_get_drvdata(ctrl);
100 struct tty_struct *tty = serport->tty;
101
102 return tty_write_room(tty);
103}
104
105static int ttyport_open(struct serdev_controller *ctrl)
106{
107 struct serport *serport = serdev_controller_get_drvdata(ctrl);
108 struct tty_struct *tty;
109 struct ktermios ktermios;
110 int ret;
111
112 tty = tty_init_dev(serport->tty_drv, serport->tty_idx);
113 if (IS_ERR(tty))
114 return PTR_ERR(tty);
115 serport->tty = tty;
116
117 if (!tty->ops->open || !tty->ops->close) {
118 ret = -ENODEV;
119 goto err_unlock;
120 }
121
122 ret = tty->ops->open(serport->tty, NULL);
123 if (ret)
124 goto err_close;
125
126 tty_unlock(serport->tty);
127
128 /* Bring the UART into a known 8 bits no parity hw fc state */
129 ktermios = tty->termios;
130 ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP |
131 INLCR | IGNCR | ICRNL | IXON);
132 ktermios.c_oflag &= ~OPOST;
133 ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
134 ktermios.c_cflag &= ~(CSIZE | PARENB);
135 ktermios.c_cflag |= CS8;
136 ktermios.c_cflag |= CRTSCTS;
137 /* Hangups are not supported so make sure to ignore carrier detect. */
138 ktermios.c_cflag |= CLOCAL;
139 tty_set_termios(tty, &ktermios);
140
141 set_bit(SERPORT_ACTIVE, &serport->flags);
142
143 return 0;
144
145err_close:
146 tty->ops->close(tty, NULL);
147err_unlock:
148 tty_unlock(tty);
149 tty_release_struct(tty, serport->tty_idx);
150
151 return ret;
152}
153
154static void ttyport_close(struct serdev_controller *ctrl)
155{
156 struct serport *serport = serdev_controller_get_drvdata(ctrl);
157 struct tty_struct *tty = serport->tty;
158
159 clear_bit(SERPORT_ACTIVE, &serport->flags);
160
161 tty_lock(tty);
162 if (tty->ops->close)
163 tty->ops->close(tty, NULL);
164 tty_unlock(tty);
165
166 tty_release_struct(tty, serport->tty_idx);
167}
168
169static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigned int speed)
170{
171 struct serport *serport = serdev_controller_get_drvdata(ctrl);
172 struct tty_struct *tty = serport->tty;
173 struct ktermios ktermios = tty->termios;
174
175 ktermios.c_cflag &= ~CBAUD;
176 tty_termios_encode_baud_rate(&ktermios, speed, speed);
177
178 /* tty_set_termios() return not checked as it is always 0 */
179 tty_set_termios(tty, &ktermios);
180 return ktermios.c_ospeed;
181}
182
183static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
184{
185 struct serport *serport = serdev_controller_get_drvdata(ctrl);
186 struct tty_struct *tty = serport->tty;
187 struct ktermios ktermios = tty->termios;
188
189 if (enable)
190 ktermios.c_cflag |= CRTSCTS;
191 else
192 ktermios.c_cflag &= ~CRTSCTS;
193
194 tty_set_termios(tty, &ktermios);
195}
196
197static int ttyport_set_parity(struct serdev_controller *ctrl,
198 enum serdev_parity parity)
199{
200 struct serport *serport = serdev_controller_get_drvdata(ctrl);
201 struct tty_struct *tty = serport->tty;
202 struct ktermios ktermios = tty->termios;
203
204 ktermios.c_cflag &= ~(PARENB | PARODD | CMSPAR);
205 if (parity != SERDEV_PARITY_NONE) {
206 ktermios.c_cflag |= PARENB;
207 if (parity == SERDEV_PARITY_ODD)
208 ktermios.c_cflag |= PARODD;
209 }
210
211 tty_set_termios(tty, &ktermios);
212
213 if ((tty->termios.c_cflag & (PARENB | PARODD | CMSPAR)) !=
214 (ktermios.c_cflag & (PARENB | PARODD | CMSPAR)))
215 return -EINVAL;
216
217 return 0;
218}
219
220static void ttyport_wait_until_sent(struct serdev_controller *ctrl, long timeout)
221{
222 struct serport *serport = serdev_controller_get_drvdata(ctrl);
223 struct tty_struct *tty = serport->tty;
224
225 tty_wait_until_sent(tty, timeout);
226}
227
228static int ttyport_get_tiocm(struct serdev_controller *ctrl)
229{
230 struct serport *serport = serdev_controller_get_drvdata(ctrl);
231 struct tty_struct *tty = serport->tty;
232
233 if (!tty->ops->tiocmget)
234 return -ENOTSUPP;
235
236 return tty->ops->tiocmget(tty);
237}
238
239static int ttyport_set_tiocm(struct serdev_controller *ctrl, unsigned int set, unsigned int clear)
240{
241 struct serport *serport = serdev_controller_get_drvdata(ctrl);
242 struct tty_struct *tty = serport->tty;
243
244 if (!tty->ops->tiocmset)
245 return -ENOTSUPP;
246
247 return tty->ops->tiocmset(tty, set, clear);
248}
249
250static const struct serdev_controller_ops ctrl_ops = {
251 .write_buf = ttyport_write_buf,
252 .write_flush = ttyport_write_flush,
253 .write_room = ttyport_write_room,
254 .open = ttyport_open,
255 .close = ttyport_close,
256 .set_flow_control = ttyport_set_flow_control,
257 .set_parity = ttyport_set_parity,
258 .set_baudrate = ttyport_set_baudrate,
259 .wait_until_sent = ttyport_wait_until_sent,
260 .get_tiocm = ttyport_get_tiocm,
261 .set_tiocm = ttyport_set_tiocm,
262};
263
264struct device *serdev_tty_port_register(struct tty_port *port,
265 struct device *parent,
266 struct tty_driver *drv, int idx)
267{
268 struct serdev_controller *ctrl;
269 struct serport *serport;
270 int ret;
271
272 if (!port || !drv || !parent)
273 return ERR_PTR(-ENODEV);
274
275 ctrl = serdev_controller_alloc(parent, sizeof(struct serport));
276 if (!ctrl)
277 return ERR_PTR(-ENOMEM);
278 serport = serdev_controller_get_drvdata(ctrl);
279
280 serport->port = port;
281 serport->tty_idx = idx;
282 serport->tty_drv = drv;
283
284 ctrl->ops = &ctrl_ops;
285
286 port->client_ops = &client_ops;
287 port->client_data = ctrl;
288
289 ret = serdev_controller_add(ctrl);
290 if (ret)
291 goto err_reset_data;
292
293 dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
294 return &ctrl->dev;
295
296err_reset_data:
297 port->client_data = NULL;
298 port->client_ops = &tty_port_default_client_ops;
299 serdev_controller_put(ctrl);
300
301 return ERR_PTR(ret);
302}
303
304int serdev_tty_port_unregister(struct tty_port *port)
305{
306 struct serdev_controller *ctrl = port->client_data;
307 struct serport *serport = serdev_controller_get_drvdata(ctrl);
308
309 if (!serport)
310 return -ENODEV;
311
312 serdev_controller_remove(ctrl);
313 port->client_data = NULL;
314 port->client_ops = &tty_port_default_client_ops;
315 serdev_controller_put(ctrl);
316
317 return 0;
318}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
4 */
5#include <linux/kernel.h>
6#include <linux/serdev.h>
7#include <linux/tty.h>
8#include <linux/tty_driver.h>
9#include <linux/poll.h>
10
11#define SERPORT_ACTIVE 1
12
13struct serport {
14 struct tty_port *port;
15 struct tty_struct *tty;
16 struct tty_driver *tty_drv;
17 int tty_idx;
18 unsigned long flags;
19};
20
21/*
22 * Callback functions from the tty port.
23 */
24
25static int ttyport_receive_buf(struct tty_port *port, const unsigned char *cp,
26 const unsigned char *fp, size_t count)
27{
28 struct serdev_controller *ctrl = port->client_data;
29 struct serport *serport = serdev_controller_get_drvdata(ctrl);
30 int ret;
31
32 if (!test_bit(SERPORT_ACTIVE, &serport->flags))
33 return 0;
34
35 ret = serdev_controller_receive_buf(ctrl, cp, count);
36
37 dev_WARN_ONCE(&ctrl->dev, ret < 0 || ret > count,
38 "receive_buf returns %d (count = %zu)\n",
39 ret, count);
40 if (ret < 0)
41 return 0;
42 else if (ret > count)
43 return count;
44
45 return ret;
46}
47
48static void ttyport_write_wakeup(struct tty_port *port)
49{
50 struct serdev_controller *ctrl = port->client_data;
51 struct serport *serport = serdev_controller_get_drvdata(ctrl);
52 struct tty_struct *tty;
53
54 tty = tty_port_tty_get(port);
55 if (!tty)
56 return;
57
58 if (test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) &&
59 test_bit(SERPORT_ACTIVE, &serport->flags))
60 serdev_controller_write_wakeup(ctrl);
61
62 /* Wake up any tty_wait_until_sent() */
63 wake_up_interruptible(&tty->write_wait);
64
65 tty_kref_put(tty);
66}
67
68static const struct tty_port_client_operations client_ops = {
69 .receive_buf = ttyport_receive_buf,
70 .write_wakeup = ttyport_write_wakeup,
71};
72
73/*
74 * Callback functions from the serdev core.
75 */
76
77static int ttyport_write_buf(struct serdev_controller *ctrl, const unsigned char *data, size_t len)
78{
79 struct serport *serport = serdev_controller_get_drvdata(ctrl);
80 struct tty_struct *tty = serport->tty;
81
82 if (!test_bit(SERPORT_ACTIVE, &serport->flags))
83 return 0;
84
85 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
86 return tty->ops->write(serport->tty, data, len);
87}
88
89static void ttyport_write_flush(struct serdev_controller *ctrl)
90{
91 struct serport *serport = serdev_controller_get_drvdata(ctrl);
92 struct tty_struct *tty = serport->tty;
93
94 tty_driver_flush_buffer(tty);
95}
96
97static int ttyport_write_room(struct serdev_controller *ctrl)
98{
99 struct serport *serport = serdev_controller_get_drvdata(ctrl);
100 struct tty_struct *tty = serport->tty;
101
102 return tty_write_room(tty);
103}
104
105static int ttyport_open(struct serdev_controller *ctrl)
106{
107 struct serport *serport = serdev_controller_get_drvdata(ctrl);
108 struct tty_struct *tty;
109 struct ktermios ktermios;
110 int ret;
111
112 tty = tty_init_dev(serport->tty_drv, serport->tty_idx);
113 if (IS_ERR(tty))
114 return PTR_ERR(tty);
115 serport->tty = tty;
116
117 if (!tty->ops->open || !tty->ops->close) {
118 ret = -ENODEV;
119 goto err_unlock;
120 }
121
122 ret = tty->ops->open(serport->tty, NULL);
123 if (ret)
124 goto err_close;
125
126 tty_unlock(serport->tty);
127
128 /* Bring the UART into a known 8 bits no parity hw fc state */
129 ktermios = tty->termios;
130 ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP |
131 INLCR | IGNCR | ICRNL | IXON);
132 ktermios.c_oflag &= ~OPOST;
133 ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
134 ktermios.c_cflag &= ~(CSIZE | PARENB);
135 ktermios.c_cflag |= CS8;
136 ktermios.c_cflag |= CRTSCTS;
137 /* Hangups are not supported so make sure to ignore carrier detect. */
138 ktermios.c_cflag |= CLOCAL;
139 tty_set_termios(tty, &ktermios);
140
141 set_bit(SERPORT_ACTIVE, &serport->flags);
142
143 return 0;
144
145err_close:
146 tty->ops->close(tty, NULL);
147err_unlock:
148 tty_unlock(tty);
149 tty_release_struct(tty, serport->tty_idx);
150
151 return ret;
152}
153
154static void ttyport_close(struct serdev_controller *ctrl)
155{
156 struct serport *serport = serdev_controller_get_drvdata(ctrl);
157 struct tty_struct *tty = serport->tty;
158
159 clear_bit(SERPORT_ACTIVE, &serport->flags);
160
161 tty_lock(tty);
162 if (tty->ops->close)
163 tty->ops->close(tty, NULL);
164 tty_unlock(tty);
165
166 tty_release_struct(tty, serport->tty_idx);
167}
168
169static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigned int speed)
170{
171 struct serport *serport = serdev_controller_get_drvdata(ctrl);
172 struct tty_struct *tty = serport->tty;
173 struct ktermios ktermios = tty->termios;
174
175 ktermios.c_cflag &= ~CBAUD;
176 tty_termios_encode_baud_rate(&ktermios, speed, speed);
177
178 /* tty_set_termios() return not checked as it is always 0 */
179 tty_set_termios(tty, &ktermios);
180 return ktermios.c_ospeed;
181}
182
183static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
184{
185 struct serport *serport = serdev_controller_get_drvdata(ctrl);
186 struct tty_struct *tty = serport->tty;
187 struct ktermios ktermios = tty->termios;
188
189 if (enable)
190 ktermios.c_cflag |= CRTSCTS;
191 else
192 ktermios.c_cflag &= ~CRTSCTS;
193
194 tty_set_termios(tty, &ktermios);
195}
196
197static int ttyport_set_parity(struct serdev_controller *ctrl,
198 enum serdev_parity parity)
199{
200 struct serport *serport = serdev_controller_get_drvdata(ctrl);
201 struct tty_struct *tty = serport->tty;
202 struct ktermios ktermios = tty->termios;
203
204 ktermios.c_cflag &= ~(PARENB | PARODD | CMSPAR);
205 if (parity != SERDEV_PARITY_NONE) {
206 ktermios.c_cflag |= PARENB;
207 if (parity == SERDEV_PARITY_ODD)
208 ktermios.c_cflag |= PARODD;
209 }
210
211 tty_set_termios(tty, &ktermios);
212
213 if ((tty->termios.c_cflag & (PARENB | PARODD | CMSPAR)) !=
214 (ktermios.c_cflag & (PARENB | PARODD | CMSPAR)))
215 return -EINVAL;
216
217 return 0;
218}
219
220static void ttyport_wait_until_sent(struct serdev_controller *ctrl, long timeout)
221{
222 struct serport *serport = serdev_controller_get_drvdata(ctrl);
223 struct tty_struct *tty = serport->tty;
224
225 tty_wait_until_sent(tty, timeout);
226}
227
228static int ttyport_get_tiocm(struct serdev_controller *ctrl)
229{
230 struct serport *serport = serdev_controller_get_drvdata(ctrl);
231 struct tty_struct *tty = serport->tty;
232
233 if (!tty->ops->tiocmget)
234 return -ENOTSUPP;
235
236 return tty->ops->tiocmget(tty);
237}
238
239static int ttyport_set_tiocm(struct serdev_controller *ctrl, unsigned int set, unsigned int clear)
240{
241 struct serport *serport = serdev_controller_get_drvdata(ctrl);
242 struct tty_struct *tty = serport->tty;
243
244 if (!tty->ops->tiocmset)
245 return -ENOTSUPP;
246
247 return tty->ops->tiocmset(tty, set, clear);
248}
249
250static const struct serdev_controller_ops ctrl_ops = {
251 .write_buf = ttyport_write_buf,
252 .write_flush = ttyport_write_flush,
253 .write_room = ttyport_write_room,
254 .open = ttyport_open,
255 .close = ttyport_close,
256 .set_flow_control = ttyport_set_flow_control,
257 .set_parity = ttyport_set_parity,
258 .set_baudrate = ttyport_set_baudrate,
259 .wait_until_sent = ttyport_wait_until_sent,
260 .get_tiocm = ttyport_get_tiocm,
261 .set_tiocm = ttyport_set_tiocm,
262};
263
264struct device *serdev_tty_port_register(struct tty_port *port,
265 struct device *parent,
266 struct tty_driver *drv, int idx)
267{
268 struct serdev_controller *ctrl;
269 struct serport *serport;
270 int ret;
271
272 if (!port || !drv || !parent)
273 return ERR_PTR(-ENODEV);
274
275 ctrl = serdev_controller_alloc(parent, sizeof(struct serport));
276 if (!ctrl)
277 return ERR_PTR(-ENOMEM);
278 serport = serdev_controller_get_drvdata(ctrl);
279
280 serport->port = port;
281 serport->tty_idx = idx;
282 serport->tty_drv = drv;
283
284 ctrl->ops = &ctrl_ops;
285
286 port->client_ops = &client_ops;
287 port->client_data = ctrl;
288
289 ret = serdev_controller_add(ctrl);
290 if (ret)
291 goto err_reset_data;
292
293 dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
294 return &ctrl->dev;
295
296err_reset_data:
297 port->client_data = NULL;
298 port->client_ops = &tty_port_default_client_ops;
299 serdev_controller_put(ctrl);
300
301 return ERR_PTR(ret);
302}
303
304int serdev_tty_port_unregister(struct tty_port *port)
305{
306 struct serdev_controller *ctrl = port->client_data;
307 struct serport *serport = serdev_controller_get_drvdata(ctrl);
308
309 if (!serport)
310 return -ENODEV;
311
312 serdev_controller_remove(ctrl);
313 port->client_data = NULL;
314 port->client_ops = &tty_port_default_client_ops;
315 serdev_controller_put(ctrl);
316
317 return 0;
318}