Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
62b74942 | 2 | * SCLP VT220 terminal driver. |
1da177e4 | 3 | * |
62b74942 MH |
4 | * Copyright IBM Corp. 2003, 2009 |
5 | * | |
6 | * Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com> | |
1da177e4 LT |
7 | */ |
8 | ||
1da177e4 LT |
9 | #include <linux/module.h> |
10 | #include <linux/spinlock.h> | |
11 | #include <linux/list.h> | |
12 | #include <linux/wait.h> | |
13 | #include <linux/timer.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/tty.h> | |
16 | #include <linux/tty_driver.h> | |
33f0f88f | 17 | #include <linux/tty_flip.h> |
1da177e4 LT |
18 | #include <linux/errno.h> |
19 | #include <linux/mm.h> | |
20 | #include <linux/major.h> | |
21 | #include <linux/console.h> | |
22 | #include <linux/kdev_t.h> | |
1da177e4 LT |
23 | #include <linux/interrupt.h> |
24 | #include <linux/init.h> | |
2332ce1a | 25 | #include <linux/reboot.h> |
5a0e3ad6 | 26 | #include <linux/slab.h> |
2332ce1a | 27 | |
1da177e4 LT |
28 | #include <asm/uaccess.h> |
29 | #include "sclp.h" | |
30 | ||
1da177e4 LT |
31 | #define SCLP_VT220_MAJOR TTY_MAJOR |
32 | #define SCLP_VT220_MINOR 65 | |
33 | #define SCLP_VT220_DRIVER_NAME "sclp_vt220" | |
34 | #define SCLP_VT220_DEVICE_NAME "ttysclp" | |
35 | #define SCLP_VT220_CONSOLE_NAME "ttyS" | |
36 | #define SCLP_VT220_CONSOLE_INDEX 1 /* console=ttyS1 */ | |
37 | #define SCLP_VT220_BUF_SIZE 80 | |
38 | ||
39 | /* Representation of a single write request */ | |
40 | struct sclp_vt220_request { | |
41 | struct list_head list; | |
42 | struct sclp_req sclp_req; | |
43 | int retry_count; | |
44 | }; | |
45 | ||
46 | /* VT220 SCCB */ | |
47 | struct sclp_vt220_sccb { | |
48 | struct sccb_header header; | |
49 | struct evbuf_header evbuf; | |
50 | }; | |
51 | ||
52 | #define SCLP_VT220_MAX_CHARS_PER_BUFFER (PAGE_SIZE - \ | |
53 | sizeof(struct sclp_vt220_request) - \ | |
54 | sizeof(struct sclp_vt220_sccb)) | |
55 | ||
56 | /* Structures and data needed to register tty driver */ | |
57 | static struct tty_driver *sclp_vt220_driver; | |
58 | ||
59 | /* The tty_struct that the kernel associated with us */ | |
60 | static struct tty_struct *sclp_vt220_tty; | |
61 | ||
62 | /* Lock to protect internal data from concurrent access */ | |
63 | static spinlock_t sclp_vt220_lock; | |
64 | ||
65 | /* List of empty pages to be used as write request buffers */ | |
66 | static struct list_head sclp_vt220_empty; | |
67 | ||
68 | /* List of pending requests */ | |
69 | static struct list_head sclp_vt220_outqueue; | |
70 | ||
62b74942 MH |
71 | /* Suspend mode flag */ |
72 | static int sclp_vt220_suspended; | |
73 | ||
74 | /* Flag that output queue is currently running */ | |
75 | static int sclp_vt220_queue_running; | |
1da177e4 | 76 | |
1da177e4 LT |
77 | /* Timer used for delaying write requests to merge subsequent messages into |
78 | * a single buffer */ | |
79 | static struct timer_list sclp_vt220_timer; | |
80 | ||
81 | /* Pointer to current request buffer which has been partially filled but not | |
82 | * yet sent */ | |
83 | static struct sclp_vt220_request *sclp_vt220_current_request; | |
84 | ||
85 | /* Number of characters in current request buffer */ | |
86 | static int sclp_vt220_buffered_chars; | |
87 | ||
ad211790 PO |
88 | /* Counter controlling core driver initialization. */ |
89 | static int __initdata sclp_vt220_init_count; | |
1da177e4 LT |
90 | |
91 | /* Flag indicating that sclp_vt220_current_request should really | |
92 | * have been already queued but wasn't because the SCLP was processing | |
93 | * another buffer */ | |
94 | static int sclp_vt220_flush_later; | |
95 | ||
96 | static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf); | |
62b74942 MH |
97 | static void sclp_vt220_pm_event_fn(struct sclp_register *reg, |
98 | enum sclp_pm_event sclp_pm_event); | |
1da177e4 LT |
99 | static int __sclp_vt220_emit(struct sclp_vt220_request *request); |
100 | static void sclp_vt220_emit_current(void); | |
101 | ||
102 | /* Registration structure for our interest in SCLP event buffers */ | |
103 | static struct sclp_register sclp_vt220_register = { | |
6d4740c8 SH |
104 | .send_mask = EVTYP_VT220MSG_MASK, |
105 | .receive_mask = EVTYP_VT220MSG_MASK, | |
1da177e4 | 106 | .state_change_fn = NULL, |
62b74942 MH |
107 | .receiver_fn = sclp_vt220_receiver_fn, |
108 | .pm_event_fn = sclp_vt220_pm_event_fn, | |
1da177e4 LT |
109 | }; |
110 | ||
111 | ||
112 | /* | |
113 | * Put provided request buffer back into queue and check emit pending | |
114 | * buffers if necessary. | |
115 | */ | |
116 | static void | |
117 | sclp_vt220_process_queue(struct sclp_vt220_request *request) | |
118 | { | |
119 | unsigned long flags; | |
120 | void *page; | |
121 | ||
122 | do { | |
123 | /* Put buffer back to list of empty buffers */ | |
124 | page = request->sclp_req.sccb; | |
125 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
126 | /* Move request from outqueue to empty queue */ | |
127 | list_del(&request->list); | |
1da177e4 LT |
128 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); |
129 | /* Check if there is a pending buffer on the out queue. */ | |
130 | request = NULL; | |
131 | if (!list_empty(&sclp_vt220_outqueue)) | |
132 | request = list_entry(sclp_vt220_outqueue.next, | |
133 | struct sclp_vt220_request, list); | |
62b74942 MH |
134 | if (!request || sclp_vt220_suspended) { |
135 | sclp_vt220_queue_running = 0; | |
136 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
137 | break; | |
138 | } | |
1da177e4 | 139 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
62b74942 | 140 | } while (__sclp_vt220_emit(request)); |
1da177e4 LT |
141 | if (request == NULL && sclp_vt220_flush_later) |
142 | sclp_vt220_emit_current(); | |
1da177e4 LT |
143 | /* Check if the tty needs a wake up call */ |
144 | if (sclp_vt220_tty != NULL) { | |
145 | tty_wakeup(sclp_vt220_tty); | |
146 | } | |
147 | } | |
148 | ||
149 | #define SCLP_BUFFER_MAX_RETRY 1 | |
150 | ||
151 | /* | |
152 | * Callback through which the result of a write request is reported by the | |
153 | * SCLP. | |
154 | */ | |
155 | static void | |
156 | sclp_vt220_callback(struct sclp_req *request, void *data) | |
157 | { | |
158 | struct sclp_vt220_request *vt220_request; | |
159 | struct sclp_vt220_sccb *sccb; | |
160 | ||
161 | vt220_request = (struct sclp_vt220_request *) data; | |
162 | if (request->status == SCLP_REQ_FAILED) { | |
163 | sclp_vt220_process_queue(vt220_request); | |
164 | return; | |
165 | } | |
166 | sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb; | |
167 | ||
168 | /* Check SCLP response code and choose suitable action */ | |
169 | switch (sccb->header.response_code) { | |
170 | case 0x0020 : | |
171 | break; | |
172 | ||
173 | case 0x05f0: /* Target resource in improper state */ | |
174 | break; | |
175 | ||
176 | case 0x0340: /* Contained SCLP equipment check */ | |
177 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
178 | break; | |
179 | /* Remove processed buffers and requeue rest */ | |
180 | if (sclp_remove_processed((struct sccb_header *) sccb) > 0) { | |
181 | /* Not all buffers were processed */ | |
182 | sccb->header.response_code = 0x0000; | |
183 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
184 | if (sclp_add_request(request) == 0) | |
185 | return; | |
186 | } | |
187 | break; | |
188 | ||
189 | case 0x0040: /* SCLP equipment check */ | |
190 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
191 | break; | |
192 | sccb->header.response_code = 0x0000; | |
193 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
194 | if (sclp_add_request(request) == 0) | |
195 | return; | |
196 | break; | |
197 | ||
198 | default: | |
199 | break; | |
200 | } | |
201 | sclp_vt220_process_queue(vt220_request); | |
202 | } | |
203 | ||
204 | /* | |
205 | * Emit vt220 request buffer to SCLP. Return zero on success, non-zero | |
206 | * otherwise. | |
207 | */ | |
208 | static int | |
209 | __sclp_vt220_emit(struct sclp_vt220_request *request) | |
210 | { | |
d082d3ce | 211 | if (!(sclp_vt220_register.sclp_receive_mask & EVTYP_VT220MSG_MASK)) { |
1da177e4 LT |
212 | request->sclp_req.status = SCLP_REQ_FAILED; |
213 | return -EIO; | |
214 | } | |
ab14de6c | 215 | request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA; |
1da177e4 LT |
216 | request->sclp_req.status = SCLP_REQ_FILLED; |
217 | request->sclp_req.callback = sclp_vt220_callback; | |
218 | request->sclp_req.callback_data = (void *) request; | |
219 | ||
220 | return sclp_add_request(&request->sclp_req); | |
221 | } | |
222 | ||
223 | /* | |
62b74942 | 224 | * Queue and emit current request. |
1da177e4 LT |
225 | */ |
226 | static void | |
227 | sclp_vt220_emit_current(void) | |
228 | { | |
229 | unsigned long flags; | |
230 | struct sclp_vt220_request *request; | |
231 | struct sclp_vt220_sccb *sccb; | |
232 | ||
233 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
62b74942 | 234 | if (sclp_vt220_current_request) { |
1da177e4 LT |
235 | sccb = (struct sclp_vt220_sccb *) |
236 | sclp_vt220_current_request->sclp_req.sccb; | |
237 | /* Only emit buffers with content */ | |
238 | if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) { | |
62b74942 MH |
239 | list_add_tail(&sclp_vt220_current_request->list, |
240 | &sclp_vt220_outqueue); | |
1da177e4 LT |
241 | sclp_vt220_current_request = NULL; |
242 | if (timer_pending(&sclp_vt220_timer)) | |
243 | del_timer(&sclp_vt220_timer); | |
244 | } | |
245 | sclp_vt220_flush_later = 0; | |
246 | } | |
62b74942 MH |
247 | if (sclp_vt220_queue_running || sclp_vt220_suspended) |
248 | goto out_unlock; | |
249 | if (list_empty(&sclp_vt220_outqueue)) | |
250 | goto out_unlock; | |
251 | request = list_first_entry(&sclp_vt220_outqueue, | |
252 | struct sclp_vt220_request, list); | |
253 | sclp_vt220_queue_running = 1; | |
254 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
255 | ||
256 | if (__sclp_vt220_emit(request)) | |
257 | sclp_vt220_process_queue(request); | |
258 | return; | |
259 | out_unlock: | |
1da177e4 | 260 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
1da177e4 LT |
261 | } |
262 | ||
263 | #define SCLP_NORMAL_WRITE 0x00 | |
264 | ||
265 | /* | |
266 | * Helper function to initialize a page with the sclp request structure. | |
267 | */ | |
268 | static struct sclp_vt220_request * | |
269 | sclp_vt220_initialize_page(void *page) | |
270 | { | |
271 | struct sclp_vt220_request *request; | |
272 | struct sclp_vt220_sccb *sccb; | |
273 | ||
274 | /* Place request structure at end of page */ | |
275 | request = ((struct sclp_vt220_request *) | |
276 | ((addr_t) page + PAGE_SIZE)) - 1; | |
277 | request->retry_count = 0; | |
278 | request->sclp_req.sccb = page; | |
279 | /* SCCB goes at start of page */ | |
280 | sccb = (struct sclp_vt220_sccb *) page; | |
281 | memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb)); | |
282 | sccb->header.length = sizeof(struct sclp_vt220_sccb); | |
283 | sccb->header.function_code = SCLP_NORMAL_WRITE; | |
284 | sccb->header.response_code = 0x0000; | |
6d4740c8 | 285 | sccb->evbuf.type = EVTYP_VT220MSG; |
1da177e4 LT |
286 | sccb->evbuf.length = sizeof(struct evbuf_header); |
287 | ||
288 | return request; | |
289 | } | |
290 | ||
291 | static inline unsigned int | |
292 | sclp_vt220_space_left(struct sclp_vt220_request *request) | |
293 | { | |
294 | struct sclp_vt220_sccb *sccb; | |
295 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
296 | return PAGE_SIZE - sizeof(struct sclp_vt220_request) - | |
297 | sccb->header.length; | |
298 | } | |
299 | ||
300 | static inline unsigned int | |
301 | sclp_vt220_chars_stored(struct sclp_vt220_request *request) | |
302 | { | |
303 | struct sclp_vt220_sccb *sccb; | |
304 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
305 | return sccb->evbuf.length - sizeof(struct evbuf_header); | |
306 | } | |
307 | ||
308 | /* | |
309 | * Add msg to buffer associated with request. Return the number of characters | |
310 | * added. | |
311 | */ | |
312 | static int | |
313 | sclp_vt220_add_msg(struct sclp_vt220_request *request, | |
314 | const unsigned char *msg, int count, int convertlf) | |
315 | { | |
316 | struct sclp_vt220_sccb *sccb; | |
317 | void *buffer; | |
318 | unsigned char c; | |
319 | int from; | |
320 | int to; | |
321 | ||
322 | if (count > sclp_vt220_space_left(request)) | |
323 | count = sclp_vt220_space_left(request); | |
324 | if (count <= 0) | |
325 | return 0; | |
326 | ||
327 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
328 | buffer = (void *) ((addr_t) sccb + sccb->header.length); | |
329 | ||
330 | if (convertlf) { | |
331 | /* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/ | |
332 | for (from=0, to=0; | |
333 | (from < count) && (to < sclp_vt220_space_left(request)); | |
334 | from++) { | |
335 | /* Retrieve character */ | |
336 | c = msg[from]; | |
337 | /* Perform conversion */ | |
338 | if (c == 0x0a) { | |
339 | if (to + 1 < sclp_vt220_space_left(request)) { | |
340 | ((unsigned char *) buffer)[to++] = c; | |
341 | ((unsigned char *) buffer)[to++] = 0x0d; | |
342 | } else | |
343 | break; | |
344 | ||
345 | } else | |
346 | ((unsigned char *) buffer)[to++] = c; | |
347 | } | |
348 | sccb->header.length += to; | |
349 | sccb->evbuf.length += to; | |
350 | return from; | |
351 | } else { | |
352 | memcpy(buffer, (const void *) msg, count); | |
353 | sccb->header.length += count; | |
354 | sccb->evbuf.length += count; | |
355 | return count; | |
356 | } | |
357 | } | |
358 | ||
359 | /* | |
360 | * Emit buffer after having waited long enough for more data to arrive. | |
361 | */ | |
362 | static void | |
363 | sclp_vt220_timeout(unsigned long data) | |
364 | { | |
365 | sclp_vt220_emit_current(); | |
366 | } | |
367 | ||
fa331ffc | 368 | #define BUFFER_MAX_DELAY HZ/20 |
1da177e4 LT |
369 | |
370 | /* | |
371 | * Internal implementation of the write function. Write COUNT bytes of data | |
372 | * from memory at BUF | |
373 | * to the SCLP interface. In case that the data does not fit into the current | |
374 | * write buffer, emit the current one and allocate a new one. If there are no | |
375 | * more empty buffers available, wait until one gets emptied. If DO_SCHEDULE | |
376 | * is non-zero, the buffer will be scheduled for emitting after a timeout - | |
377 | * otherwise the user has to explicitly call the flush function. | |
378 | * A non-zero CONVERTLF parameter indicates that 0x0a characters in the message | |
379 | * buffer should be converted to 0x0a 0x0d. After completion, return the number | |
380 | * of bytes written. | |
381 | */ | |
382 | static int | |
383 | __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule, | |
d4820e44 | 384 | int convertlf, int may_fail) |
1da177e4 LT |
385 | { |
386 | unsigned long flags; | |
387 | void *page; | |
388 | int written; | |
389 | int overall_written; | |
390 | ||
391 | if (count <= 0) | |
392 | return 0; | |
393 | overall_written = 0; | |
394 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
395 | do { | |
d4820e44 | 396 | /* Create an sclp output buffer if none exists yet */ |
1da177e4 LT |
397 | if (sclp_vt220_current_request == NULL) { |
398 | while (list_empty(&sclp_vt220_empty)) { | |
d1e23375 | 399 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
62b74942 | 400 | if (may_fail || sclp_vt220_suspended) |
d4820e44 | 401 | goto out; |
1da177e4 | 402 | else |
d4820e44 | 403 | sclp_sync_wait(); |
1da177e4 LT |
404 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
405 | } | |
406 | page = (void *) sclp_vt220_empty.next; | |
407 | list_del((struct list_head *) page); | |
408 | sclp_vt220_current_request = | |
409 | sclp_vt220_initialize_page(page); | |
410 | } | |
411 | /* Try to write the string to the current request buffer */ | |
412 | written = sclp_vt220_add_msg(sclp_vt220_current_request, | |
413 | buf, count, convertlf); | |
414 | overall_written += written; | |
415 | if (written == count) | |
416 | break; | |
417 | /* | |
418 | * Not all characters could be written to the current | |
419 | * output buffer. Emit the buffer, create a new buffer | |
420 | * and then output the rest of the string. | |
421 | */ | |
422 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
423 | sclp_vt220_emit_current(); | |
424 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
425 | buf += written; | |
426 | count -= written; | |
427 | } while (count > 0); | |
428 | /* Setup timer to output current console buffer after some time */ | |
429 | if (sclp_vt220_current_request != NULL && | |
430 | !timer_pending(&sclp_vt220_timer) && do_schedule) { | |
431 | sclp_vt220_timer.function = sclp_vt220_timeout; | |
432 | sclp_vt220_timer.data = 0UL; | |
433 | sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY; | |
434 | add_timer(&sclp_vt220_timer); | |
435 | } | |
436 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
d4820e44 | 437 | out: |
1da177e4 LT |
438 | return overall_written; |
439 | } | |
440 | ||
441 | /* | |
442 | * This routine is called by the kernel to write a series of | |
443 | * characters to the tty device. The characters may come from | |
444 | * user space or kernel space. This routine will return the | |
445 | * number of characters actually accepted for writing. | |
446 | */ | |
447 | static int | |
448 | sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count) | |
449 | { | |
d1e23375 | 450 | return __sclp_vt220_write(buf, count, 1, 0, 1); |
1da177e4 LT |
451 | } |
452 | ||
453 | #define SCLP_VT220_SESSION_ENDED 0x01 | |
454 | #define SCLP_VT220_SESSION_STARTED 0x80 | |
455 | #define SCLP_VT220_SESSION_DATA 0x00 | |
456 | ||
457 | /* | |
458 | * Called by the SCLP to report incoming event buffers. | |
459 | */ | |
460 | static void | |
461 | sclp_vt220_receiver_fn(struct evbuf_header *evbuf) | |
462 | { | |
463 | char *buffer; | |
464 | unsigned int count; | |
465 | ||
466 | /* Ignore input if device is not open */ | |
467 | if (sclp_vt220_tty == NULL) | |
468 | return; | |
469 | ||
470 | buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header)); | |
471 | count = evbuf->length - sizeof(struct evbuf_header); | |
472 | ||
473 | switch (*buffer) { | |
474 | case SCLP_VT220_SESSION_ENDED: | |
475 | case SCLP_VT220_SESSION_STARTED: | |
476 | break; | |
477 | case SCLP_VT220_SESSION_DATA: | |
478 | /* Send input to line discipline */ | |
479 | buffer++; | |
480 | count--; | |
33f0f88f | 481 | tty_insert_flip_string(sclp_vt220_tty, buffer, count); |
1da177e4 LT |
482 | tty_flip_buffer_push(sclp_vt220_tty); |
483 | break; | |
484 | } | |
485 | } | |
486 | ||
487 | /* | |
488 | * This routine is called when a particular tty device is opened. | |
489 | */ | |
490 | static int | |
491 | sclp_vt220_open(struct tty_struct *tty, struct file *filp) | |
492 | { | |
493 | if (tty->count == 1) { | |
494 | sclp_vt220_tty = tty; | |
495 | tty->driver_data = kmalloc(SCLP_VT220_BUF_SIZE, GFP_KERNEL); | |
496 | if (tty->driver_data == NULL) | |
497 | return -ENOMEM; | |
498 | tty->low_latency = 0; | |
0b665d77 HB |
499 | if (!tty->winsize.ws_row && !tty->winsize.ws_col) { |
500 | tty->winsize.ws_row = 24; | |
501 | tty->winsize.ws_col = 80; | |
502 | } | |
1da177e4 LT |
503 | } |
504 | return 0; | |
505 | } | |
506 | ||
507 | /* | |
508 | * This routine is called when a particular tty device is closed. | |
509 | */ | |
510 | static void | |
511 | sclp_vt220_close(struct tty_struct *tty, struct file *filp) | |
512 | { | |
513 | if (tty->count == 1) { | |
514 | sclp_vt220_tty = NULL; | |
515 | kfree(tty->driver_data); | |
516 | tty->driver_data = NULL; | |
517 | } | |
518 | } | |
519 | ||
520 | /* | |
521 | * This routine is called by the kernel to write a single | |
522 | * character to the tty device. If the kernel uses this routine, | |
523 | * it must call the flush_chars() routine (if defined) when it is | |
524 | * done stuffing characters into the driver. | |
1da177e4 | 525 | */ |
9e7c9a19 | 526 | static int |
1da177e4 LT |
527 | sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch) |
528 | { | |
d4820e44 | 529 | return __sclp_vt220_write(&ch, 1, 0, 0, 1); |
1da177e4 LT |
530 | } |
531 | ||
532 | /* | |
533 | * This routine is called by the kernel after it has written a | |
534 | * series of characters to the tty device using put_char(). | |
535 | */ | |
536 | static void | |
537 | sclp_vt220_flush_chars(struct tty_struct *tty) | |
538 | { | |
62b74942 | 539 | if (!sclp_vt220_queue_running) |
1da177e4 LT |
540 | sclp_vt220_emit_current(); |
541 | else | |
542 | sclp_vt220_flush_later = 1; | |
543 | } | |
544 | ||
545 | /* | |
546 | * This routine returns the numbers of characters the tty driver | |
547 | * will accept for queuing to be written. This number is subject | |
548 | * to change as output buffers get emptied, or if the output flow | |
549 | * control is acted. | |
550 | */ | |
551 | static int | |
552 | sclp_vt220_write_room(struct tty_struct *tty) | |
553 | { | |
554 | unsigned long flags; | |
555 | struct list_head *l; | |
556 | int count; | |
557 | ||
558 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
559 | count = 0; | |
560 | if (sclp_vt220_current_request != NULL) | |
561 | count = sclp_vt220_space_left(sclp_vt220_current_request); | |
562 | list_for_each(l, &sclp_vt220_empty) | |
563 | count += SCLP_VT220_MAX_CHARS_PER_BUFFER; | |
564 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
565 | return count; | |
566 | } | |
567 | ||
568 | /* | |
569 | * Return number of buffered chars. | |
570 | */ | |
571 | static int | |
572 | sclp_vt220_chars_in_buffer(struct tty_struct *tty) | |
573 | { | |
574 | unsigned long flags; | |
575 | struct list_head *l; | |
576 | struct sclp_vt220_request *r; | |
577 | int count; | |
578 | ||
579 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
580 | count = 0; | |
581 | if (sclp_vt220_current_request != NULL) | |
582 | count = sclp_vt220_chars_stored(sclp_vt220_current_request); | |
583 | list_for_each(l, &sclp_vt220_outqueue) { | |
584 | r = list_entry(l, struct sclp_vt220_request, list); | |
585 | count += sclp_vt220_chars_stored(r); | |
586 | } | |
587 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
588 | return count; | |
589 | } | |
590 | ||
1da177e4 LT |
591 | /* |
592 | * Pass on all buffers to the hardware. Return only when there are no more | |
593 | * buffers pending. | |
594 | */ | |
595 | static void | |
596 | sclp_vt220_flush_buffer(struct tty_struct *tty) | |
597 | { | |
598 | sclp_vt220_emit_current(); | |
599 | } | |
600 | ||
ad211790 PO |
601 | /* Release allocated pages. */ |
602 | static void __init __sclp_vt220_free_pages(void) | |
5aaaf9f0 HC |
603 | { |
604 | struct list_head *page, *p; | |
605 | ||
606 | list_for_each_safe(page, p, &sclp_vt220_empty) { | |
607 | list_del(page); | |
5c0792f6 | 608 | free_page((unsigned long) page); |
5aaaf9f0 HC |
609 | } |
610 | } | |
611 | ||
ad211790 PO |
612 | /* Release memory and unregister from sclp core. Controlled by init counting - |
613 | * only the last invoker will actually perform these actions. */ | |
614 | static void __init __sclp_vt220_cleanup(void) | |
615 | { | |
616 | sclp_vt220_init_count--; | |
617 | if (sclp_vt220_init_count != 0) | |
618 | return; | |
619 | sclp_unregister(&sclp_vt220_register); | |
620 | __sclp_vt220_free_pages(); | |
621 | } | |
622 | ||
623 | /* Allocate buffer pages and register with sclp core. Controlled by init | |
624 | * counting - only the first invoker will actually perform these actions. */ | |
625 | static int __init __sclp_vt220_init(int num_pages) | |
1da177e4 LT |
626 | { |
627 | void *page; | |
628 | int i; | |
59eb1ca7 | 629 | int rc; |
1da177e4 | 630 | |
ad211790 PO |
631 | sclp_vt220_init_count++; |
632 | if (sclp_vt220_init_count != 1) | |
1da177e4 | 633 | return 0; |
1da177e4 LT |
634 | spin_lock_init(&sclp_vt220_lock); |
635 | INIT_LIST_HEAD(&sclp_vt220_empty); | |
636 | INIT_LIST_HEAD(&sclp_vt220_outqueue); | |
1da177e4 LT |
637 | init_timer(&sclp_vt220_timer); |
638 | sclp_vt220_current_request = NULL; | |
639 | sclp_vt220_buffered_chars = 0; | |
1da177e4 LT |
640 | sclp_vt220_tty = NULL; |
641 | sclp_vt220_flush_later = 0; | |
642 | ||
643 | /* Allocate pages for output buffering */ | |
5c0792f6 | 644 | rc = -ENOMEM; |
5aaaf9f0 | 645 | for (i = 0; i < num_pages; i++) { |
5c0792f6 HC |
646 | page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
647 | if (!page) | |
ad211790 | 648 | goto out; |
5c0792f6 | 649 | list_add_tail(page, &sclp_vt220_empty); |
1da177e4 | 650 | } |
59eb1ca7 | 651 | rc = sclp_register(&sclp_vt220_register); |
ad211790 | 652 | out: |
59eb1ca7 | 653 | if (rc) { |
ad211790 PO |
654 | __sclp_vt220_free_pages(); |
655 | sclp_vt220_init_count--; | |
59eb1ca7 CB |
656 | } |
657 | return rc; | |
1da177e4 LT |
658 | } |
659 | ||
b68e31d0 | 660 | static const struct tty_operations sclp_vt220_ops = { |
1da177e4 LT |
661 | .open = sclp_vt220_open, |
662 | .close = sclp_vt220_close, | |
663 | .write = sclp_vt220_write, | |
664 | .put_char = sclp_vt220_put_char, | |
665 | .flush_chars = sclp_vt220_flush_chars, | |
666 | .write_room = sclp_vt220_write_room, | |
667 | .chars_in_buffer = sclp_vt220_chars_in_buffer, | |
5aaaf9f0 | 668 | .flush_buffer = sclp_vt220_flush_buffer, |
1da177e4 LT |
669 | }; |
670 | ||
671 | /* | |
672 | * Register driver with SCLP and Linux and initialize internal tty structures. | |
673 | */ | |
5aaaf9f0 | 674 | static int __init sclp_vt220_tty_init(void) |
1da177e4 LT |
675 | { |
676 | struct tty_driver *driver; | |
677 | int rc; | |
678 | ||
679 | /* Note: we're not testing for CONSOLE_IS_SCLP here to preserve | |
680 | * symmetry between VM and LPAR systems regarding ttyS1. */ | |
681 | driver = alloc_tty_driver(1); | |
682 | if (!driver) | |
683 | return -ENOMEM; | |
ad211790 | 684 | rc = __sclp_vt220_init(MAX_KMEM_PAGES); |
5aaaf9f0 HC |
685 | if (rc) |
686 | goto out_driver; | |
1da177e4 LT |
687 | |
688 | driver->owner = THIS_MODULE; | |
689 | driver->driver_name = SCLP_VT220_DRIVER_NAME; | |
690 | driver->name = SCLP_VT220_DEVICE_NAME; | |
691 | driver->major = SCLP_VT220_MAJOR; | |
692 | driver->minor_start = SCLP_VT220_MINOR; | |
693 | driver->type = TTY_DRIVER_TYPE_SYSTEM; | |
694 | driver->subtype = SYSTEM_TYPE_TTY; | |
695 | driver->init_termios = tty_std_termios; | |
696 | driver->flags = TTY_DRIVER_REAL_RAW; | |
697 | tty_set_operations(driver, &sclp_vt220_ops); | |
698 | ||
699 | rc = tty_register_driver(driver); | |
a12c53f4 | 700 | if (rc) |
59eb1ca7 | 701 | goto out_init; |
1da177e4 LT |
702 | sclp_vt220_driver = driver; |
703 | return 0; | |
1da177e4 | 704 | |
5aaaf9f0 | 705 | out_init: |
ad211790 | 706 | __sclp_vt220_cleanup(); |
5aaaf9f0 HC |
707 | out_driver: |
708 | put_tty_driver(driver); | |
709 | return rc; | |
710 | } | |
711 | __initcall(sclp_vt220_tty_init); | |
1da177e4 | 712 | |
b3b59d33 HC |
713 | static void __sclp_vt220_flush_buffer(void) |
714 | { | |
715 | unsigned long flags; | |
716 | ||
717 | sclp_vt220_emit_current(); | |
718 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
719 | if (timer_pending(&sclp_vt220_timer)) | |
720 | del_timer(&sclp_vt220_timer); | |
62b74942 | 721 | while (sclp_vt220_queue_running) { |
b3b59d33 HC |
722 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
723 | sclp_sync_wait(); | |
724 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
725 | } | |
726 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
727 | } | |
728 | ||
62b74942 MH |
729 | /* |
730 | * Resume console: If there are cached messages, emit them. | |
731 | */ | |
732 | static void sclp_vt220_resume(void) | |
733 | { | |
734 | unsigned long flags; | |
735 | ||
736 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
737 | sclp_vt220_suspended = 0; | |
738 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
739 | sclp_vt220_emit_current(); | |
740 | } | |
741 | ||
742 | /* | |
743 | * Suspend console: Set suspend flag and flush console | |
744 | */ | |
745 | static void sclp_vt220_suspend(void) | |
746 | { | |
747 | unsigned long flags; | |
748 | ||
749 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
750 | sclp_vt220_suspended = 1; | |
751 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
752 | __sclp_vt220_flush_buffer(); | |
753 | } | |
754 | ||
755 | static void sclp_vt220_pm_event_fn(struct sclp_register *reg, | |
756 | enum sclp_pm_event sclp_pm_event) | |
757 | { | |
758 | switch (sclp_pm_event) { | |
759 | case SCLP_PM_EVENT_FREEZE: | |
760 | sclp_vt220_suspend(); | |
761 | break; | |
762 | case SCLP_PM_EVENT_RESTORE: | |
763 | case SCLP_PM_EVENT_THAW: | |
764 | sclp_vt220_resume(); | |
765 | break; | |
766 | } | |
767 | } | |
768 | ||
ac522b63 MH |
769 | #ifdef CONFIG_SCLP_VT220_CONSOLE |
770 | ||
771 | static void | |
772 | sclp_vt220_con_write(struct console *con, const char *buf, unsigned int count) | |
773 | { | |
774 | __sclp_vt220_write((const unsigned char *) buf, count, 1, 1, 0); | |
775 | } | |
776 | ||
777 | static struct tty_driver * | |
778 | sclp_vt220_con_device(struct console *c, int *index) | |
779 | { | |
780 | *index = 0; | |
781 | return sclp_vt220_driver; | |
782 | } | |
783 | ||
2332ce1a HS |
784 | static int |
785 | sclp_vt220_notify(struct notifier_block *self, | |
786 | unsigned long event, void *data) | |
1da177e4 LT |
787 | { |
788 | __sclp_vt220_flush_buffer(); | |
2332ce1a | 789 | return NOTIFY_OK; |
1da177e4 LT |
790 | } |
791 | ||
2332ce1a HS |
792 | static struct notifier_block on_panic_nb = { |
793 | .notifier_call = sclp_vt220_notify, | |
794 | .priority = 1, | |
795 | }; | |
796 | ||
797 | static struct notifier_block on_reboot_nb = { | |
798 | .notifier_call = sclp_vt220_notify, | |
799 | .priority = 1, | |
800 | }; | |
801 | ||
1da177e4 LT |
802 | /* Structure needed to register with printk */ |
803 | static struct console sclp_vt220_console = | |
804 | { | |
805 | .name = SCLP_VT220_CONSOLE_NAME, | |
806 | .write = sclp_vt220_con_write, | |
807 | .device = sclp_vt220_con_device, | |
1da177e4 LT |
808 | .flags = CON_PRINTBUFFER, |
809 | .index = SCLP_VT220_CONSOLE_INDEX | |
810 | }; | |
811 | ||
812 | static int __init | |
813 | sclp_vt220_con_init(void) | |
814 | { | |
815 | int rc; | |
816 | ||
817 | if (!CONSOLE_IS_SCLP) | |
818 | return 0; | |
ad211790 | 819 | rc = __sclp_vt220_init(MAX_CONSOLE_PAGES); |
1da177e4 LT |
820 | if (rc) |
821 | return rc; | |
822 | /* Attach linux console */ | |
2332ce1a HS |
823 | atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); |
824 | register_reboot_notifier(&on_reboot_nb); | |
1da177e4 LT |
825 | register_console(&sclp_vt220_console); |
826 | return 0; | |
827 | } | |
828 | ||
829 | console_initcall(sclp_vt220_con_init); | |
830 | #endif /* CONFIG_SCLP_VT220_CONSOLE */ | |
831 |