Commit | Line | Data |
---|---|---|
9e48565d AC |
1 | /* |
2 | * Tty port functions | |
3 | */ | |
4 | ||
5 | #include <linux/types.h> | |
6 | #include <linux/errno.h> | |
7 | #include <linux/tty.h> | |
8 | #include <linux/tty_driver.h> | |
9 | #include <linux/tty_flip.h> | |
3e61696b | 10 | #include <linux/serial.h> |
9e48565d AC |
11 | #include <linux/timer.h> |
12 | #include <linux/string.h> | |
13 | #include <linux/slab.h> | |
14 | #include <linux/sched.h> | |
9e48565d AC |
15 | #include <linux/wait.h> |
16 | #include <linux/bitops.h> | |
17 | #include <linux/delay.h> | |
18 | #include <linux/module.h> | |
19 | ||
20 | void tty_port_init(struct tty_port *port) | |
21 | { | |
22 | memset(port, 0, sizeof(*port)); | |
ecbbfd44 | 23 | tty_buffer_init(port); |
9e48565d | 24 | init_waitqueue_head(&port->open_wait); |
bdc04e31 | 25 | init_waitqueue_head(&port->delta_msr_wait); |
9e48565d | 26 | mutex_init(&port->mutex); |
44e4909e | 27 | mutex_init(&port->buf_mutex); |
4a90f09b | 28 | spin_lock_init(&port->lock); |
9e48565d AC |
29 | port->close_delay = (50 * HZ) / 100; |
30 | port->closing_wait = (3000 * HZ) / 100; | |
568aafc6 | 31 | kref_init(&port->kref); |
9e48565d AC |
32 | } |
33 | EXPORT_SYMBOL(tty_port_init); | |
34 | ||
2cb4ca02 JS |
35 | /** |
36 | * tty_port_link_device - link tty and tty_port | |
37 | * @port: tty_port of the device | |
38 | * @driver: tty_driver for this device | |
39 | * @index: index of the tty | |
40 | * | |
41 | * Provide the tty layer wit ha link from a tty (specified by @index) to a | |
42 | * tty_port (@port). Use this only if neither tty_port_register_device nor | |
43 | * tty_port_install is used in the driver. If used, this has to be called before | |
44 | * tty_register_driver. | |
45 | */ | |
46 | void tty_port_link_device(struct tty_port *port, | |
47 | struct tty_driver *driver, unsigned index) | |
48 | { | |
49 | if (WARN_ON(index >= driver->num)) | |
50 | return; | |
51 | driver->ports[index] = port; | |
52 | } | |
53 | EXPORT_SYMBOL_GPL(tty_port_link_device); | |
54 | ||
72a33bf5 JS |
55 | /** |
56 | * tty_port_register_device - register tty device | |
57 | * @port: tty_port of the device | |
58 | * @driver: tty_driver for this device | |
59 | * @index: index of the tty | |
60 | * @device: parent if exists, otherwise NULL | |
61 | * | |
62 | * It is the same as tty_register_device except the provided @port is linked to | |
63 | * a concrete tty specified by @index. Use this or tty_port_install (or both). | |
64 | * Call tty_port_link_device as a last resort. | |
65 | */ | |
057eb856 JS |
66 | struct device *tty_port_register_device(struct tty_port *port, |
67 | struct tty_driver *driver, unsigned index, | |
68 | struct device *device) | |
69 | { | |
2cb4ca02 | 70 | tty_port_link_device(port, driver, index); |
057eb856 JS |
71 | return tty_register_device(driver, index, device); |
72 | } | |
73 | EXPORT_SYMBOL_GPL(tty_port_register_device); | |
74 | ||
b1b79916 TH |
75 | /** |
76 | * tty_port_register_device_attr - register tty device | |
77 | * @port: tty_port of the device | |
78 | * @driver: tty_driver for this device | |
79 | * @index: index of the tty | |
80 | * @device: parent if exists, otherwise NULL | |
81 | * @drvdata: Driver data to be set to device. | |
82 | * @attr_grp: Attribute group to be set on device. | |
83 | * | |
84 | * It is the same as tty_register_device_attr except the provided @port is | |
85 | * linked to a concrete tty specified by @index. Use this or tty_port_install | |
86 | * (or both). Call tty_port_link_device as a last resort. | |
87 | */ | |
88 | struct device *tty_port_register_device_attr(struct tty_port *port, | |
89 | struct tty_driver *driver, unsigned index, | |
90 | struct device *device, void *drvdata, | |
91 | const struct attribute_group **attr_grp) | |
92 | { | |
93 | tty_port_link_device(port, driver, index); | |
94 | return tty_register_device_attr(driver, index, device, drvdata, | |
95 | attr_grp); | |
96 | } | |
97 | EXPORT_SYMBOL_GPL(tty_port_register_device_attr); | |
98 | ||
9e48565d AC |
99 | int tty_port_alloc_xmit_buf(struct tty_port *port) |
100 | { | |
101 | /* We may sleep in get_zeroed_page() */ | |
44e4909e | 102 | mutex_lock(&port->buf_mutex); |
9e48565d AC |
103 | if (port->xmit_buf == NULL) |
104 | port->xmit_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL); | |
44e4909e | 105 | mutex_unlock(&port->buf_mutex); |
9e48565d AC |
106 | if (port->xmit_buf == NULL) |
107 | return -ENOMEM; | |
108 | return 0; | |
109 | } | |
110 | EXPORT_SYMBOL(tty_port_alloc_xmit_buf); | |
111 | ||
112 | void tty_port_free_xmit_buf(struct tty_port *port) | |
113 | { | |
44e4909e | 114 | mutex_lock(&port->buf_mutex); |
9e48565d AC |
115 | if (port->xmit_buf != NULL) { |
116 | free_page((unsigned long)port->xmit_buf); | |
117 | port->xmit_buf = NULL; | |
118 | } | |
44e4909e | 119 | mutex_unlock(&port->buf_mutex); |
9e48565d AC |
120 | } |
121 | EXPORT_SYMBOL(tty_port_free_xmit_buf); | |
122 | ||
de274bfe JS |
123 | /** |
124 | * tty_port_destroy -- destroy inited port | |
125 | * @port: tty port to be doestroyed | |
126 | * | |
127 | * When a port was initialized using tty_port_init, one has to destroy the | |
128 | * port by this function. Either indirectly by using tty_port refcounting | |
129 | * (tty_port_put) or directly if refcounting is not used. | |
130 | */ | |
131 | void tty_port_destroy(struct tty_port *port) | |
132 | { | |
e176058f | 133 | tty_buffer_cancel_work(port); |
de274bfe JS |
134 | tty_buffer_free_all(port); |
135 | } | |
136 | EXPORT_SYMBOL(tty_port_destroy); | |
137 | ||
568aafc6 AC |
138 | static void tty_port_destructor(struct kref *kref) |
139 | { | |
140 | struct tty_port *port = container_of(kref, struct tty_port, kref); | |
e3bfea23 PH |
141 | |
142 | /* check if last port ref was dropped before tty release */ | |
143 | if (WARN_ON(port->itty)) | |
144 | return; | |
568aafc6 AC |
145 | if (port->xmit_buf) |
146 | free_page((unsigned long)port->xmit_buf); | |
de274bfe | 147 | tty_port_destroy(port); |
81c79838 | 148 | if (port->ops && port->ops->destruct) |
568aafc6 AC |
149 | port->ops->destruct(port); |
150 | else | |
151 | kfree(port); | |
152 | } | |
153 | ||
154 | void tty_port_put(struct tty_port *port) | |
155 | { | |
156 | if (port) | |
157 | kref_put(&port->kref, tty_port_destructor); | |
158 | } | |
159 | EXPORT_SYMBOL(tty_port_put); | |
9e48565d | 160 | |
4a90f09b AC |
161 | /** |
162 | * tty_port_tty_get - get a tty reference | |
163 | * @port: tty port | |
164 | * | |
165 | * Return a refcount protected tty instance or NULL if the port is not | |
166 | * associated with a tty (eg due to close or hangup) | |
167 | */ | |
168 | ||
169 | struct tty_struct *tty_port_tty_get(struct tty_port *port) | |
170 | { | |
171 | unsigned long flags; | |
172 | struct tty_struct *tty; | |
173 | ||
174 | spin_lock_irqsave(&port->lock, flags); | |
175 | tty = tty_kref_get(port->tty); | |
176 | spin_unlock_irqrestore(&port->lock, flags); | |
177 | return tty; | |
178 | } | |
179 | EXPORT_SYMBOL(tty_port_tty_get); | |
180 | ||
181 | /** | |
182 | * tty_port_tty_set - set the tty of a port | |
183 | * @port: tty port | |
184 | * @tty: the tty | |
185 | * | |
186 | * Associate the port and tty pair. Manages any internal refcounts. | |
187 | * Pass NULL to deassociate a port | |
188 | */ | |
189 | ||
190 | void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty) | |
191 | { | |
192 | unsigned long flags; | |
193 | ||
194 | spin_lock_irqsave(&port->lock, flags); | |
a211b1af | 195 | tty_kref_put(port->tty); |
cb4bca35 | 196 | port->tty = tty_kref_get(tty); |
4a90f09b AC |
197 | spin_unlock_irqrestore(&port->lock, flags); |
198 | } | |
199 | EXPORT_SYMBOL(tty_port_tty_set); | |
31f35939 | 200 | |
957dacae | 201 | static void tty_port_shutdown(struct tty_port *port, struct tty_struct *tty) |
7ca0ff9a | 202 | { |
64bc3979 | 203 | mutex_lock(&port->mutex); |
8bde9658 JH |
204 | if (port->console) |
205 | goto out; | |
206 | ||
207 | if (test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags)) { | |
957dacae JH |
208 | /* |
209 | * Drop DTR/RTS if HUPCL is set. This causes any attached | |
210 | * modem to hang up the line. | |
211 | */ | |
212 | if (tty && C_HUPCL(tty)) | |
213 | tty_port_lower_dtr_rts(port); | |
214 | ||
8bde9658 | 215 | if (port->ops->shutdown) |
7ca0ff9a | 216 | port->ops->shutdown(port); |
8bde9658 JH |
217 | } |
218 | out: | |
64bc3979 | 219 | mutex_unlock(&port->mutex); |
7ca0ff9a AC |
220 | } |
221 | ||
3e61696b AC |
222 | /** |
223 | * tty_port_hangup - hangup helper | |
224 | * @port: tty port | |
225 | * | |
226 | * Perform port level tty hangup flag and count changes. Drop the tty | |
227 | * reference. | |
9c9928bd PH |
228 | * |
229 | * Caller holds tty lock. | |
3e61696b AC |
230 | */ |
231 | ||
232 | void tty_port_hangup(struct tty_port *port) | |
233 | { | |
957dacae | 234 | struct tty_struct *tty; |
3e61696b AC |
235 | unsigned long flags; |
236 | ||
237 | spin_lock_irqsave(&port->lock, flags); | |
238 | port->count = 0; | |
239 | port->flags &= ~ASYNC_NORMAL_ACTIVE; | |
957dacae JH |
240 | tty = port->tty; |
241 | if (tty) | |
242 | set_bit(TTY_IO_ERROR, &tty->flags); | |
3e61696b AC |
243 | port->tty = NULL; |
244 | spin_unlock_irqrestore(&port->lock, flags); | |
957dacae JH |
245 | tty_port_shutdown(port, tty); |
246 | tty_kref_put(tty); | |
3e61696b | 247 | wake_up_interruptible(&port->open_wait); |
bdc04e31 | 248 | wake_up_interruptible(&port->delta_msr_wait); |
3e61696b AC |
249 | } |
250 | EXPORT_SYMBOL(tty_port_hangup); | |
251 | ||
aa27a094 JS |
252 | /** |
253 | * tty_port_tty_hangup - helper to hang up a tty | |
254 | * | |
255 | * @port: tty port | |
256 | * @check_clocal: hang only ttys with CLOCAL unset? | |
257 | */ | |
258 | void tty_port_tty_hangup(struct tty_port *port, bool check_clocal) | |
259 | { | |
260 | struct tty_struct *tty = tty_port_tty_get(port); | |
261 | ||
1d9e689c | 262 | if (tty && (!check_clocal || !C_CLOCAL(tty))) |
aa27a094 | 263 | tty_hangup(tty); |
1d9e689c | 264 | tty_kref_put(tty); |
aa27a094 JS |
265 | } |
266 | EXPORT_SYMBOL_GPL(tty_port_tty_hangup); | |
267 | ||
6aad04f2 JS |
268 | /** |
269 | * tty_port_tty_wakeup - helper to wake up a tty | |
270 | * | |
271 | * @port: tty port | |
272 | */ | |
273 | void tty_port_tty_wakeup(struct tty_port *port) | |
274 | { | |
275 | struct tty_struct *tty = tty_port_tty_get(port); | |
276 | ||
277 | if (tty) { | |
278 | tty_wakeup(tty); | |
279 | tty_kref_put(tty); | |
280 | } | |
281 | } | |
282 | EXPORT_SYMBOL_GPL(tty_port_tty_wakeup); | |
283 | ||
31f35939 AC |
284 | /** |
285 | * tty_port_carrier_raised - carrier raised check | |
286 | * @port: tty port | |
287 | * | |
288 | * Wrapper for the carrier detect logic. For the moment this is used | |
289 | * to hide some internal details. This will eventually become entirely | |
290 | * internal to the tty port. | |
291 | */ | |
292 | ||
293 | int tty_port_carrier_raised(struct tty_port *port) | |
294 | { | |
295 | if (port->ops->carrier_raised == NULL) | |
296 | return 1; | |
297 | return port->ops->carrier_raised(port); | |
298 | } | |
299 | EXPORT_SYMBOL(tty_port_carrier_raised); | |
5d951fb4 AC |
300 | |
301 | /** | |
fcc8ac18 | 302 | * tty_port_raise_dtr_rts - Raise DTR/RTS |
5d951fb4 AC |
303 | * @port: tty port |
304 | * | |
305 | * Wrapper for the DTR/RTS raise logic. For the moment this is used | |
306 | * to hide some internal details. This will eventually become entirely | |
307 | * internal to the tty port. | |
308 | */ | |
309 | ||
310 | void tty_port_raise_dtr_rts(struct tty_port *port) | |
311 | { | |
fcc8ac18 AC |
312 | if (port->ops->dtr_rts) |
313 | port->ops->dtr_rts(port, 1); | |
5d951fb4 AC |
314 | } |
315 | EXPORT_SYMBOL(tty_port_raise_dtr_rts); | |
36c621d8 | 316 | |
fcc8ac18 AC |
317 | /** |
318 | * tty_port_lower_dtr_rts - Lower DTR/RTS | |
319 | * @port: tty port | |
320 | * | |
321 | * Wrapper for the DTR/RTS raise logic. For the moment this is used | |
322 | * to hide some internal details. This will eventually become entirely | |
323 | * internal to the tty port. | |
324 | */ | |
325 | ||
326 | void tty_port_lower_dtr_rts(struct tty_port *port) | |
327 | { | |
328 | if (port->ops->dtr_rts) | |
329 | port->ops->dtr_rts(port, 0); | |
330 | } | |
331 | EXPORT_SYMBOL(tty_port_lower_dtr_rts); | |
332 | ||
36c621d8 AC |
333 | /** |
334 | * tty_port_block_til_ready - Waiting logic for tty open | |
335 | * @port: the tty port being opened | |
336 | * @tty: the tty device being bound | |
337 | * @filp: the file pointer of the opener | |
338 | * | |
339 | * Implement the core POSIX/SuS tty behaviour when opening a tty device. | |
340 | * Handles: | |
341 | * - hangup (both before and during) | |
342 | * - non blocking open | |
343 | * - rts/dtr/dcd | |
344 | * - signals | |
345 | * - port flags and counts | |
346 | * | |
347 | * The passed tty_port must implement the carrier_raised method if it can | |
fcc8ac18 | 348 | * do carrier detect and the dtr_rts method if it supports software |
36c621d8 AC |
349 | * management of these lines. Note that the dtr/rts raise is done each |
350 | * iteration as a hangup may have previously dropped them while we wait. | |
c590f6b6 PH |
351 | * |
352 | * Caller holds tty lock. | |
353 | * | |
354 | * NB: May drop and reacquire tty lock when blocking, so tty and tty_port | |
355 | * may have changed state (eg., may have been hung up). | |
36c621d8 | 356 | */ |
d774a56d | 357 | |
36c621d8 AC |
358 | int tty_port_block_til_ready(struct tty_port *port, |
359 | struct tty_struct *tty, struct file *filp) | |
360 | { | |
361 | int do_clocal = 0, retval; | |
362 | unsigned long flags; | |
6af9a43d | 363 | DEFINE_WAIT(wait); |
36c621d8 | 364 | |
36c621d8 AC |
365 | /* if non-blocking mode is set we can pass directly to open unless |
366 | the port has just hung up or is in another error state */ | |
8627b96d AC |
367 | if (tty->flags & (1 << TTY_IO_ERROR)) { |
368 | port->flags |= ASYNC_NORMAL_ACTIVE; | |
369 | return 0; | |
370 | } | |
371 | if (filp->f_flags & O_NONBLOCK) { | |
4175f3e3 | 372 | /* Indicate we are open */ |
9db276f8 | 373 | if (C_BAUD(tty)) |
4175f3e3 | 374 | tty_port_raise_dtr_rts(port); |
36c621d8 AC |
375 | port->flags |= ASYNC_NORMAL_ACTIVE; |
376 | return 0; | |
377 | } | |
378 | ||
379 | if (C_CLOCAL(tty)) | |
380 | do_clocal = 1; | |
381 | ||
382 | /* Block waiting until we can proceed. We may need to wait for the | |
383 | carrier, but we must also wait for any close that is in progress | |
384 | before the next open may complete */ | |
385 | ||
386 | retval = 0; | |
36c621d8 AC |
387 | |
388 | /* The port lock protects the port counts */ | |
389 | spin_lock_irqsave(&port->lock, flags); | |
e359a4e3 | 390 | port->count--; |
36c621d8 AC |
391 | port->blocked_open++; |
392 | spin_unlock_irqrestore(&port->lock, flags); | |
393 | ||
394 | while (1) { | |
395 | /* Indicate we are open */ | |
e584a02c | 396 | if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags)) |
7834909f | 397 | tty_port_raise_dtr_rts(port); |
36c621d8 | 398 | |
3e3b5c08 | 399 | prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE); |
d774a56d AC |
400 | /* Check for a hangup or uninitialised port. |
401 | Return accordingly */ | |
36c621d8 AC |
402 | if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) { |
403 | if (port->flags & ASYNC_HUP_NOTIFY) | |
404 | retval = -EAGAIN; | |
405 | else | |
406 | retval = -ERESTARTSYS; | |
407 | break; | |
408 | } | |
0eee50af JS |
409 | /* |
410 | * Probe the carrier. For devices with no carrier detect | |
411 | * tty_port_carrier_raised will always return true. | |
412 | * Never ask drivers if CLOCAL is set, this causes troubles | |
413 | * on some hardware. | |
414 | */ | |
fef062cb | 415 | if (do_clocal || tty_port_carrier_raised(port)) |
36c621d8 AC |
416 | break; |
417 | if (signal_pending(current)) { | |
418 | retval = -ERESTARTSYS; | |
419 | break; | |
420 | } | |
89c8d91e | 421 | tty_unlock(tty); |
36c621d8 | 422 | schedule(); |
89c8d91e | 423 | tty_lock(tty); |
36c621d8 | 424 | } |
3e3b5c08 | 425 | finish_wait(&port->open_wait, &wait); |
36c621d8 AC |
426 | |
427 | /* Update counts. A parallel hangup will have set count to zero and | |
428 | we must not mess that up further */ | |
429 | spin_lock_irqsave(&port->lock, flags); | |
430 | if (!tty_hung_up_p(filp)) | |
431 | port->count++; | |
432 | port->blocked_open--; | |
433 | if (retval == 0) | |
434 | port->flags |= ASYNC_NORMAL_ACTIVE; | |
435 | spin_unlock_irqrestore(&port->lock, flags); | |
ecc2e05e | 436 | return retval; |
36c621d8 AC |
437 | } |
438 | EXPORT_SYMBOL(tty_port_block_til_ready); | |
439 | ||
b74414f5 JH |
440 | static void tty_port_drain_delay(struct tty_port *port, struct tty_struct *tty) |
441 | { | |
442 | unsigned int bps = tty_get_baud_rate(tty); | |
443 | long timeout; | |
444 | ||
445 | if (bps > 1200) { | |
446 | timeout = (HZ * 10 * port->drain_delay) / bps; | |
447 | timeout = max_t(long, timeout, HZ / 10); | |
448 | } else { | |
449 | timeout = 2 * HZ; | |
450 | } | |
451 | schedule_timeout_interruptible(timeout); | |
452 | } | |
453 | ||
79c1faa4 | 454 | /* Caller holds tty lock. */ |
d774a56d AC |
455 | int tty_port_close_start(struct tty_port *port, |
456 | struct tty_struct *tty, struct file *filp) | |
a6614999 AC |
457 | { |
458 | unsigned long flags; | |
459 | ||
633caba8 | 460 | if (tty_hung_up_p(filp)) |
a6614999 | 461 | return 0; |
a6614999 | 462 | |
633caba8 | 463 | spin_lock_irqsave(&port->lock, flags); |
d774a56d | 464 | if (tty->count == 1 && port->count != 1) { |
339f36ba PH |
465 | tty_warn(tty, "%s: tty->count = 1 port count = %d\n", __func__, |
466 | port->count); | |
a6614999 AC |
467 | port->count = 1; |
468 | } | |
469 | if (--port->count < 0) { | |
339f36ba PH |
470 | tty_warn(tty, "%s: bad port count (%d)\n", __func__, |
471 | port->count); | |
a6614999 AC |
472 | port->count = 0; |
473 | } | |
474 | ||
475 | if (port->count) { | |
476 | spin_unlock_irqrestore(&port->lock, flags); | |
477 | return 0; | |
478 | } | |
a6614999 | 479 | spin_unlock_irqrestore(&port->lock, flags); |
0b2588ca | 480 | |
ddc7b758 PH |
481 | tty->closing = 1; |
482 | ||
0b2588ca JH |
483 | if (test_bit(ASYNCB_INITIALIZED, &port->flags)) { |
484 | /* Don't block on a stalled port, just pull the chain */ | |
485 | if (tty->flow_stopped) | |
486 | tty_driver_flush_buffer(tty); | |
487 | if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) | |
79c1faa4 | 488 | tty_wait_until_sent(tty, port->closing_wait); |
0b2588ca JH |
489 | if (port->drain_delay) |
490 | tty_port_drain_delay(port, tty); | |
491 | } | |
e707c35c AC |
492 | /* Flush the ldisc buffering */ |
493 | tty_ldisc_flush(tty); | |
494 | ||
469d6d06 | 495 | /* Report to caller this is the last port reference */ |
a6614999 AC |
496 | return 1; |
497 | } | |
498 | EXPORT_SYMBOL(tty_port_close_start); | |
499 | ||
0733db91 | 500 | /* Caller holds tty lock */ |
a6614999 AC |
501 | void tty_port_close_end(struct tty_port *port, struct tty_struct *tty) |
502 | { | |
503 | unsigned long flags; | |
504 | ||
3f40f5b2 | 505 | tty_ldisc_flush(tty); |
a6614999 AC |
506 | tty->closing = 0; |
507 | ||
ddc7b758 PH |
508 | spin_lock_irqsave(&port->lock, flags); |
509 | ||
a6614999 AC |
510 | if (port->blocked_open) { |
511 | spin_unlock_irqrestore(&port->lock, flags); | |
5823323e PH |
512 | if (port->close_delay) |
513 | msleep_interruptible(jiffies_to_msecs(port->close_delay)); | |
a6614999 AC |
514 | spin_lock_irqsave(&port->lock, flags); |
515 | wake_up_interruptible(&port->open_wait); | |
516 | } | |
afc5ab09 | 517 | port->flags &= ~ASYNC_NORMAL_ACTIVE; |
a6614999 AC |
518 | spin_unlock_irqrestore(&port->lock, flags); |
519 | } | |
520 | EXPORT_SYMBOL(tty_port_close_end); | |
7ca0ff9a | 521 | |
0733db91 PH |
522 | /** |
523 | * tty_port_close | |
524 | * | |
525 | * Caller holds tty lock | |
0733db91 | 526 | */ |
7ca0ff9a AC |
527 | void tty_port_close(struct tty_port *port, struct tty_struct *tty, |
528 | struct file *filp) | |
529 | { | |
530 | if (tty_port_close_start(port, tty, filp) == 0) | |
531 | return; | |
957dacae | 532 | tty_port_shutdown(port, tty); |
d74e8286 | 533 | set_bit(TTY_IO_ERROR, &tty->flags); |
7ca0ff9a AC |
534 | tty_port_close_end(port, tty); |
535 | tty_port_tty_set(port, NULL); | |
536 | } | |
537 | EXPORT_SYMBOL(tty_port_close); | |
64bc3979 | 538 | |
72a33bf5 JS |
539 | /** |
540 | * tty_port_install - generic tty->ops->install handler | |
541 | * @port: tty_port of the device | |
542 | * @driver: tty_driver for this device | |
543 | * @tty: tty to be installed | |
544 | * | |
545 | * It is the same as tty_standard_install except the provided @port is linked | |
546 | * to a concrete tty specified by @tty. Use this or tty_port_register_device | |
547 | * (or both). Call tty_port_link_device as a last resort. | |
548 | */ | |
695586ca JS |
549 | int tty_port_install(struct tty_port *port, struct tty_driver *driver, |
550 | struct tty_struct *tty) | |
551 | { | |
552 | tty->port = port; | |
553 | return tty_standard_install(driver, tty); | |
554 | } | |
555 | EXPORT_SYMBOL_GPL(tty_port_install); | |
556 | ||
addd4672 PH |
557 | /** |
558 | * tty_port_open | |
559 | * | |
560 | * Caller holds tty lock. | |
561 | * | |
562 | * NB: may drop and reacquire tty lock (in tty_port_block_til_ready()) so | |
563 | * tty and tty_port may have changed state (eg., may be hung up now) | |
564 | */ | |
64bc3979 | 565 | int tty_port_open(struct tty_port *port, struct tty_struct *tty, |
d774a56d | 566 | struct file *filp) |
64bc3979 AC |
567 | { |
568 | spin_lock_irq(&port->lock); | |
e359a4e3 | 569 | ++port->count; |
64bc3979 AC |
570 | spin_unlock_irq(&port->lock); |
571 | tty_port_tty_set(port, tty); | |
572 | ||
573 | /* | |
574 | * Do the device-specific open only if the hardware isn't | |
575 | * already initialized. Serialize open and shutdown using the | |
576 | * port mutex. | |
577 | */ | |
578 | ||
579 | mutex_lock(&port->mutex); | |
580 | ||
581 | if (!test_bit(ASYNCB_INITIALIZED, &port->flags)) { | |
a9a37ec3 | 582 | clear_bit(TTY_IO_ERROR, &tty->flags); |
64bc3979 AC |
583 | if (port->ops->activate) { |
584 | int retval = port->ops->activate(port, tty); | |
585 | if (retval) { | |
d774a56d AC |
586 | mutex_unlock(&port->mutex); |
587 | return retval; | |
588 | } | |
589 | } | |
64bc3979 AC |
590 | set_bit(ASYNCB_INITIALIZED, &port->flags); |
591 | } | |
592 | mutex_unlock(&port->mutex); | |
593 | return tty_port_block_til_ready(port, tty, filp); | |
594 | } | |
595 | ||
596 | EXPORT_SYMBOL(tty_port_open); |