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 */ | |
1da177e4 LT |
37 | |
38 | /* Representation of a single write request */ | |
39 | struct sclp_vt220_request { | |
40 | struct list_head list; | |
41 | struct sclp_req sclp_req; | |
42 | int retry_count; | |
43 | }; | |
44 | ||
45 | /* VT220 SCCB */ | |
46 | struct sclp_vt220_sccb { | |
47 | struct sccb_header header; | |
48 | struct evbuf_header evbuf; | |
49 | }; | |
50 | ||
51 | #define SCLP_VT220_MAX_CHARS_PER_BUFFER (PAGE_SIZE - \ | |
52 | sizeof(struct sclp_vt220_request) - \ | |
53 | sizeof(struct sclp_vt220_sccb)) | |
54 | ||
55 | /* Structures and data needed to register tty driver */ | |
56 | static struct tty_driver *sclp_vt220_driver; | |
57 | ||
092f7377 | 58 | static struct tty_port sclp_vt220_port; |
1da177e4 LT |
59 | |
60 | /* Lock to protect internal data from concurrent access */ | |
61 | static spinlock_t sclp_vt220_lock; | |
62 | ||
63 | /* List of empty pages to be used as write request buffers */ | |
64 | static struct list_head sclp_vt220_empty; | |
65 | ||
66 | /* List of pending requests */ | |
67 | static struct list_head sclp_vt220_outqueue; | |
68 | ||
62b74942 MH |
69 | /* Suspend mode flag */ |
70 | static int sclp_vt220_suspended; | |
71 | ||
72 | /* Flag that output queue is currently running */ | |
73 | static int sclp_vt220_queue_running; | |
1da177e4 | 74 | |
1da177e4 LT |
75 | /* Timer used for delaying write requests to merge subsequent messages into |
76 | * a single buffer */ | |
77 | static struct timer_list sclp_vt220_timer; | |
78 | ||
79 | /* Pointer to current request buffer which has been partially filled but not | |
80 | * yet sent */ | |
81 | static struct sclp_vt220_request *sclp_vt220_current_request; | |
82 | ||
83 | /* Number of characters in current request buffer */ | |
84 | static int sclp_vt220_buffered_chars; | |
85 | ||
ad211790 PO |
86 | /* Counter controlling core driver initialization. */ |
87 | static int __initdata sclp_vt220_init_count; | |
1da177e4 LT |
88 | |
89 | /* Flag indicating that sclp_vt220_current_request should really | |
90 | * have been already queued but wasn't because the SCLP was processing | |
91 | * another buffer */ | |
92 | static int sclp_vt220_flush_later; | |
93 | ||
94 | static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf); | |
62b74942 MH |
95 | static void sclp_vt220_pm_event_fn(struct sclp_register *reg, |
96 | enum sclp_pm_event sclp_pm_event); | |
1da177e4 LT |
97 | static int __sclp_vt220_emit(struct sclp_vt220_request *request); |
98 | static void sclp_vt220_emit_current(void); | |
99 | ||
e106e4ea | 100 | /* Registration structure for SCLP output event buffers */ |
1da177e4 | 101 | static struct sclp_register sclp_vt220_register = { |
6d4740c8 | 102 | .send_mask = EVTYP_VT220MSG_MASK, |
e106e4ea PO |
103 | .pm_event_fn = sclp_vt220_pm_event_fn, |
104 | }; | |
105 | ||
106 | /* Registration structure for SCLP input event buffers */ | |
107 | static struct sclp_register sclp_vt220_register_input = { | |
6d4740c8 | 108 | .receive_mask = EVTYP_VT220MSG_MASK, |
62b74942 | 109 | .receiver_fn = sclp_vt220_receiver_fn, |
1da177e4 LT |
110 | }; |
111 | ||
112 | ||
113 | /* | |
114 | * Put provided request buffer back into queue and check emit pending | |
115 | * buffers if necessary. | |
116 | */ | |
117 | static void | |
118 | sclp_vt220_process_queue(struct sclp_vt220_request *request) | |
119 | { | |
120 | unsigned long flags; | |
121 | void *page; | |
122 | ||
123 | do { | |
124 | /* Put buffer back to list of empty buffers */ | |
125 | page = request->sclp_req.sccb; | |
126 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
127 | /* Move request from outqueue to empty queue */ | |
128 | list_del(&request->list); | |
1da177e4 LT |
129 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); |
130 | /* Check if there is a pending buffer on the out queue. */ | |
131 | request = NULL; | |
132 | if (!list_empty(&sclp_vt220_outqueue)) | |
133 | request = list_entry(sclp_vt220_outqueue.next, | |
134 | struct sclp_vt220_request, list); | |
62b74942 MH |
135 | if (!request || sclp_vt220_suspended) { |
136 | sclp_vt220_queue_running = 0; | |
137 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
138 | break; | |
139 | } | |
1da177e4 | 140 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
62b74942 | 141 | } while (__sclp_vt220_emit(request)); |
1da177e4 LT |
142 | if (request == NULL && sclp_vt220_flush_later) |
143 | sclp_vt220_emit_current(); | |
6aad04f2 | 144 | tty_port_tty_wakeup(&sclp_vt220_port); |
1da177e4 LT |
145 | } |
146 | ||
147 | #define SCLP_BUFFER_MAX_RETRY 1 | |
148 | ||
149 | /* | |
150 | * Callback through which the result of a write request is reported by the | |
151 | * SCLP. | |
152 | */ | |
153 | static void | |
154 | sclp_vt220_callback(struct sclp_req *request, void *data) | |
155 | { | |
156 | struct sclp_vt220_request *vt220_request; | |
157 | struct sclp_vt220_sccb *sccb; | |
158 | ||
159 | vt220_request = (struct sclp_vt220_request *) data; | |
160 | if (request->status == SCLP_REQ_FAILED) { | |
161 | sclp_vt220_process_queue(vt220_request); | |
162 | return; | |
163 | } | |
164 | sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb; | |
165 | ||
166 | /* Check SCLP response code and choose suitable action */ | |
167 | switch (sccb->header.response_code) { | |
168 | case 0x0020 : | |
169 | break; | |
170 | ||
171 | case 0x05f0: /* Target resource in improper state */ | |
172 | break; | |
173 | ||
174 | case 0x0340: /* Contained SCLP equipment check */ | |
175 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
176 | break; | |
177 | /* Remove processed buffers and requeue rest */ | |
178 | if (sclp_remove_processed((struct sccb_header *) sccb) > 0) { | |
179 | /* Not all buffers were processed */ | |
180 | sccb->header.response_code = 0x0000; | |
181 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
182 | if (sclp_add_request(request) == 0) | |
183 | return; | |
184 | } | |
185 | break; | |
186 | ||
187 | case 0x0040: /* SCLP equipment check */ | |
188 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
189 | break; | |
190 | sccb->header.response_code = 0x0000; | |
191 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
192 | if (sclp_add_request(request) == 0) | |
193 | return; | |
194 | break; | |
195 | ||
196 | default: | |
197 | break; | |
198 | } | |
199 | sclp_vt220_process_queue(vt220_request); | |
200 | } | |
201 | ||
202 | /* | |
203 | * Emit vt220 request buffer to SCLP. Return zero on success, non-zero | |
204 | * otherwise. | |
205 | */ | |
206 | static int | |
207 | __sclp_vt220_emit(struct sclp_vt220_request *request) | |
208 | { | |
ab14de6c | 209 | request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA; |
1da177e4 LT |
210 | request->sclp_req.status = SCLP_REQ_FILLED; |
211 | request->sclp_req.callback = sclp_vt220_callback; | |
212 | request->sclp_req.callback_data = (void *) request; | |
213 | ||
214 | return sclp_add_request(&request->sclp_req); | |
215 | } | |
216 | ||
217 | /* | |
62b74942 | 218 | * Queue and emit current request. |
1da177e4 LT |
219 | */ |
220 | static void | |
221 | sclp_vt220_emit_current(void) | |
222 | { | |
223 | unsigned long flags; | |
224 | struct sclp_vt220_request *request; | |
225 | struct sclp_vt220_sccb *sccb; | |
226 | ||
227 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
62b74942 | 228 | if (sclp_vt220_current_request) { |
1da177e4 LT |
229 | sccb = (struct sclp_vt220_sccb *) |
230 | sclp_vt220_current_request->sclp_req.sccb; | |
231 | /* Only emit buffers with content */ | |
232 | if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) { | |
62b74942 MH |
233 | list_add_tail(&sclp_vt220_current_request->list, |
234 | &sclp_vt220_outqueue); | |
1da177e4 LT |
235 | sclp_vt220_current_request = NULL; |
236 | if (timer_pending(&sclp_vt220_timer)) | |
237 | del_timer(&sclp_vt220_timer); | |
238 | } | |
239 | sclp_vt220_flush_later = 0; | |
240 | } | |
62b74942 MH |
241 | if (sclp_vt220_queue_running || sclp_vt220_suspended) |
242 | goto out_unlock; | |
243 | if (list_empty(&sclp_vt220_outqueue)) | |
244 | goto out_unlock; | |
245 | request = list_first_entry(&sclp_vt220_outqueue, | |
246 | struct sclp_vt220_request, list); | |
247 | sclp_vt220_queue_running = 1; | |
248 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
249 | ||
250 | if (__sclp_vt220_emit(request)) | |
251 | sclp_vt220_process_queue(request); | |
252 | return; | |
253 | out_unlock: | |
1da177e4 | 254 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
1da177e4 LT |
255 | } |
256 | ||
257 | #define SCLP_NORMAL_WRITE 0x00 | |
258 | ||
259 | /* | |
260 | * Helper function to initialize a page with the sclp request structure. | |
261 | */ | |
262 | static struct sclp_vt220_request * | |
263 | sclp_vt220_initialize_page(void *page) | |
264 | { | |
265 | struct sclp_vt220_request *request; | |
266 | struct sclp_vt220_sccb *sccb; | |
267 | ||
268 | /* Place request structure at end of page */ | |
269 | request = ((struct sclp_vt220_request *) | |
270 | ((addr_t) page + PAGE_SIZE)) - 1; | |
271 | request->retry_count = 0; | |
272 | request->sclp_req.sccb = page; | |
273 | /* SCCB goes at start of page */ | |
274 | sccb = (struct sclp_vt220_sccb *) page; | |
275 | memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb)); | |
276 | sccb->header.length = sizeof(struct sclp_vt220_sccb); | |
277 | sccb->header.function_code = SCLP_NORMAL_WRITE; | |
278 | sccb->header.response_code = 0x0000; | |
6d4740c8 | 279 | sccb->evbuf.type = EVTYP_VT220MSG; |
1da177e4 LT |
280 | sccb->evbuf.length = sizeof(struct evbuf_header); |
281 | ||
282 | return request; | |
283 | } | |
284 | ||
285 | static inline unsigned int | |
286 | sclp_vt220_space_left(struct sclp_vt220_request *request) | |
287 | { | |
288 | struct sclp_vt220_sccb *sccb; | |
289 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
290 | return PAGE_SIZE - sizeof(struct sclp_vt220_request) - | |
291 | sccb->header.length; | |
292 | } | |
293 | ||
294 | static inline unsigned int | |
295 | sclp_vt220_chars_stored(struct sclp_vt220_request *request) | |
296 | { | |
297 | struct sclp_vt220_sccb *sccb; | |
298 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
299 | return sccb->evbuf.length - sizeof(struct evbuf_header); | |
300 | } | |
301 | ||
302 | /* | |
303 | * Add msg to buffer associated with request. Return the number of characters | |
304 | * added. | |
305 | */ | |
306 | static int | |
307 | sclp_vt220_add_msg(struct sclp_vt220_request *request, | |
308 | const unsigned char *msg, int count, int convertlf) | |
309 | { | |
310 | struct sclp_vt220_sccb *sccb; | |
311 | void *buffer; | |
312 | unsigned char c; | |
313 | int from; | |
314 | int to; | |
315 | ||
316 | if (count > sclp_vt220_space_left(request)) | |
317 | count = sclp_vt220_space_left(request); | |
318 | if (count <= 0) | |
319 | return 0; | |
320 | ||
321 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
322 | buffer = (void *) ((addr_t) sccb + sccb->header.length); | |
323 | ||
324 | if (convertlf) { | |
325 | /* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/ | |
326 | for (from=0, to=0; | |
327 | (from < count) && (to < sclp_vt220_space_left(request)); | |
328 | from++) { | |
329 | /* Retrieve character */ | |
330 | c = msg[from]; | |
331 | /* Perform conversion */ | |
332 | if (c == 0x0a) { | |
333 | if (to + 1 < sclp_vt220_space_left(request)) { | |
334 | ((unsigned char *) buffer)[to++] = c; | |
335 | ((unsigned char *) buffer)[to++] = 0x0d; | |
336 | } else | |
337 | break; | |
338 | ||
339 | } else | |
340 | ((unsigned char *) buffer)[to++] = c; | |
341 | } | |
342 | sccb->header.length += to; | |
343 | sccb->evbuf.length += to; | |
344 | return from; | |
345 | } else { | |
346 | memcpy(buffer, (const void *) msg, count); | |
347 | sccb->header.length += count; | |
348 | sccb->evbuf.length += count; | |
349 | return count; | |
350 | } | |
351 | } | |
352 | ||
353 | /* | |
354 | * Emit buffer after having waited long enough for more data to arrive. | |
355 | */ | |
356 | static void | |
357 | sclp_vt220_timeout(unsigned long data) | |
358 | { | |
359 | sclp_vt220_emit_current(); | |
360 | } | |
361 | ||
fa331ffc | 362 | #define BUFFER_MAX_DELAY HZ/20 |
1da177e4 | 363 | |
25b41a7b MS |
364 | /* |
365 | * Drop oldest console buffer if sclp_con_drop is set | |
366 | */ | |
367 | static int | |
368 | sclp_vt220_drop_buffer(void) | |
369 | { | |
370 | struct list_head *list; | |
371 | struct sclp_vt220_request *request; | |
372 | void *page; | |
373 | ||
374 | if (!sclp_console_drop) | |
375 | return 0; | |
376 | list = sclp_vt220_outqueue.next; | |
377 | if (sclp_vt220_queue_running) | |
378 | /* The first element is in I/O */ | |
379 | list = list->next; | |
380 | if (list == &sclp_vt220_outqueue) | |
381 | return 0; | |
382 | list_del(list); | |
383 | request = list_entry(list, struct sclp_vt220_request, list); | |
384 | page = request->sclp_req.sccb; | |
385 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); | |
386 | return 1; | |
387 | } | |
388 | ||
1da177e4 LT |
389 | /* |
390 | * Internal implementation of the write function. Write COUNT bytes of data | |
391 | * from memory at BUF | |
392 | * to the SCLP interface. In case that the data does not fit into the current | |
393 | * write buffer, emit the current one and allocate a new one. If there are no | |
394 | * more empty buffers available, wait until one gets emptied. If DO_SCHEDULE | |
395 | * is non-zero, the buffer will be scheduled for emitting after a timeout - | |
396 | * otherwise the user has to explicitly call the flush function. | |
397 | * A non-zero CONVERTLF parameter indicates that 0x0a characters in the message | |
398 | * buffer should be converted to 0x0a 0x0d. After completion, return the number | |
399 | * of bytes written. | |
400 | */ | |
401 | static int | |
402 | __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule, | |
d4820e44 | 403 | int convertlf, int may_fail) |
1da177e4 LT |
404 | { |
405 | unsigned long flags; | |
406 | void *page; | |
407 | int written; | |
408 | int overall_written; | |
409 | ||
410 | if (count <= 0) | |
411 | return 0; | |
412 | overall_written = 0; | |
413 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
414 | do { | |
d4820e44 | 415 | /* Create an sclp output buffer if none exists yet */ |
1da177e4 | 416 | if (sclp_vt220_current_request == NULL) { |
25b41a7b MS |
417 | if (list_empty(&sclp_vt220_empty)) |
418 | sclp_console_full++; | |
1da177e4 | 419 | while (list_empty(&sclp_vt220_empty)) { |
62b74942 | 420 | if (may_fail || sclp_vt220_suspended) |
d4820e44 | 421 | goto out; |
25b41a7b MS |
422 | if (sclp_vt220_drop_buffer()) |
423 | break; | |
424 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
425 | ||
426 | sclp_sync_wait(); | |
1da177e4 LT |
427 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
428 | } | |
429 | page = (void *) sclp_vt220_empty.next; | |
430 | list_del((struct list_head *) page); | |
431 | sclp_vt220_current_request = | |
432 | sclp_vt220_initialize_page(page); | |
433 | } | |
434 | /* Try to write the string to the current request buffer */ | |
435 | written = sclp_vt220_add_msg(sclp_vt220_current_request, | |
436 | buf, count, convertlf); | |
437 | overall_written += written; | |
438 | if (written == count) | |
439 | break; | |
440 | /* | |
441 | * Not all characters could be written to the current | |
442 | * output buffer. Emit the buffer, create a new buffer | |
443 | * and then output the rest of the string. | |
444 | */ | |
445 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
446 | sclp_vt220_emit_current(); | |
447 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
448 | buf += written; | |
449 | count -= written; | |
450 | } while (count > 0); | |
451 | /* Setup timer to output current console buffer after some time */ | |
452 | if (sclp_vt220_current_request != NULL && | |
453 | !timer_pending(&sclp_vt220_timer) && do_schedule) { | |
454 | sclp_vt220_timer.function = sclp_vt220_timeout; | |
455 | sclp_vt220_timer.data = 0UL; | |
456 | sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY; | |
457 | add_timer(&sclp_vt220_timer); | |
458 | } | |
d4820e44 | 459 | out: |
25b41a7b | 460 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
1da177e4 LT |
461 | return overall_written; |
462 | } | |
463 | ||
464 | /* | |
465 | * This routine is called by the kernel to write a series of | |
466 | * characters to the tty device. The characters may come from | |
467 | * user space or kernel space. This routine will return the | |
468 | * number of characters actually accepted for writing. | |
469 | */ | |
470 | static int | |
471 | sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count) | |
472 | { | |
d1e23375 | 473 | return __sclp_vt220_write(buf, count, 1, 0, 1); |
1da177e4 LT |
474 | } |
475 | ||
476 | #define SCLP_VT220_SESSION_ENDED 0x01 | |
477 | #define SCLP_VT220_SESSION_STARTED 0x80 | |
478 | #define SCLP_VT220_SESSION_DATA 0x00 | |
479 | ||
480 | /* | |
481 | * Called by the SCLP to report incoming event buffers. | |
482 | */ | |
483 | static void | |
484 | sclp_vt220_receiver_fn(struct evbuf_header *evbuf) | |
485 | { | |
486 | char *buffer; | |
487 | unsigned int count; | |
488 | ||
1da177e4 LT |
489 | buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header)); |
490 | count = evbuf->length - sizeof(struct evbuf_header); | |
491 | ||
492 | switch (*buffer) { | |
493 | case SCLP_VT220_SESSION_ENDED: | |
494 | case SCLP_VT220_SESSION_STARTED: | |
495 | break; | |
496 | case SCLP_VT220_SESSION_DATA: | |
497 | /* Send input to line discipline */ | |
498 | buffer++; | |
499 | count--; | |
05c7cd39 | 500 | tty_insert_flip_string(&sclp_vt220_port, buffer, count); |
2e124b4a | 501 | tty_flip_buffer_push(&sclp_vt220_port); |
1da177e4 LT |
502 | break; |
503 | } | |
504 | } | |
505 | ||
506 | /* | |
507 | * This routine is called when a particular tty device is opened. | |
508 | */ | |
509 | static int | |
510 | sclp_vt220_open(struct tty_struct *tty, struct file *filp) | |
511 | { | |
512 | if (tty->count == 1) { | |
092f7377 | 513 | tty_port_tty_set(&sclp_vt220_port, tty); |
d6c53c0e | 514 | sclp_vt220_port.low_latency = 0; |
0b665d77 HB |
515 | if (!tty->winsize.ws_row && !tty->winsize.ws_col) { |
516 | tty->winsize.ws_row = 24; | |
517 | tty->winsize.ws_col = 80; | |
518 | } | |
1da177e4 LT |
519 | } |
520 | return 0; | |
521 | } | |
522 | ||
523 | /* | |
524 | * This routine is called when a particular tty device is closed. | |
525 | */ | |
526 | static void | |
527 | sclp_vt220_close(struct tty_struct *tty, struct file *filp) | |
528 | { | |
b538c4ea | 529 | if (tty->count == 1) |
092f7377 | 530 | tty_port_tty_set(&sclp_vt220_port, NULL); |
1da177e4 LT |
531 | } |
532 | ||
533 | /* | |
534 | * This routine is called by the kernel to write a single | |
535 | * character to the tty device. If the kernel uses this routine, | |
536 | * it must call the flush_chars() routine (if defined) when it is | |
537 | * done stuffing characters into the driver. | |
1da177e4 | 538 | */ |
9e7c9a19 | 539 | static int |
1da177e4 LT |
540 | sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch) |
541 | { | |
d4820e44 | 542 | return __sclp_vt220_write(&ch, 1, 0, 0, 1); |
1da177e4 LT |
543 | } |
544 | ||
545 | /* | |
546 | * This routine is called by the kernel after it has written a | |
547 | * series of characters to the tty device using put_char(). | |
548 | */ | |
549 | static void | |
550 | sclp_vt220_flush_chars(struct tty_struct *tty) | |
551 | { | |
62b74942 | 552 | if (!sclp_vt220_queue_running) |
1da177e4 LT |
553 | sclp_vt220_emit_current(); |
554 | else | |
555 | sclp_vt220_flush_later = 1; | |
556 | } | |
557 | ||
558 | /* | |
559 | * This routine returns the numbers of characters the tty driver | |
560 | * will accept for queuing to be written. This number is subject | |
561 | * to change as output buffers get emptied, or if the output flow | |
562 | * control is acted. | |
563 | */ | |
564 | static int | |
565 | sclp_vt220_write_room(struct tty_struct *tty) | |
566 | { | |
567 | unsigned long flags; | |
568 | struct list_head *l; | |
569 | int count; | |
570 | ||
571 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
572 | count = 0; | |
573 | if (sclp_vt220_current_request != NULL) | |
574 | count = sclp_vt220_space_left(sclp_vt220_current_request); | |
575 | list_for_each(l, &sclp_vt220_empty) | |
576 | count += SCLP_VT220_MAX_CHARS_PER_BUFFER; | |
577 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
578 | return count; | |
579 | } | |
580 | ||
581 | /* | |
582 | * Return number of buffered chars. | |
583 | */ | |
584 | static int | |
585 | sclp_vt220_chars_in_buffer(struct tty_struct *tty) | |
586 | { | |
587 | unsigned long flags; | |
588 | struct list_head *l; | |
589 | struct sclp_vt220_request *r; | |
590 | int count; | |
591 | ||
592 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
593 | count = 0; | |
594 | if (sclp_vt220_current_request != NULL) | |
595 | count = sclp_vt220_chars_stored(sclp_vt220_current_request); | |
596 | list_for_each(l, &sclp_vt220_outqueue) { | |
597 | r = list_entry(l, struct sclp_vt220_request, list); | |
598 | count += sclp_vt220_chars_stored(r); | |
599 | } | |
600 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
601 | return count; | |
602 | } | |
603 | ||
1da177e4 LT |
604 | /* |
605 | * Pass on all buffers to the hardware. Return only when there are no more | |
606 | * buffers pending. | |
607 | */ | |
608 | static void | |
609 | sclp_vt220_flush_buffer(struct tty_struct *tty) | |
610 | { | |
611 | sclp_vt220_emit_current(); | |
612 | } | |
613 | ||
ad211790 PO |
614 | /* Release allocated pages. */ |
615 | static void __init __sclp_vt220_free_pages(void) | |
5aaaf9f0 HC |
616 | { |
617 | struct list_head *page, *p; | |
618 | ||
619 | list_for_each_safe(page, p, &sclp_vt220_empty) { | |
620 | list_del(page); | |
5c0792f6 | 621 | free_page((unsigned long) page); |
5aaaf9f0 HC |
622 | } |
623 | } | |
624 | ||
ad211790 PO |
625 | /* Release memory and unregister from sclp core. Controlled by init counting - |
626 | * only the last invoker will actually perform these actions. */ | |
627 | static void __init __sclp_vt220_cleanup(void) | |
628 | { | |
629 | sclp_vt220_init_count--; | |
630 | if (sclp_vt220_init_count != 0) | |
631 | return; | |
632 | sclp_unregister(&sclp_vt220_register); | |
633 | __sclp_vt220_free_pages(); | |
191c5f10 | 634 | tty_port_destroy(&sclp_vt220_port); |
ad211790 PO |
635 | } |
636 | ||
637 | /* Allocate buffer pages and register with sclp core. Controlled by init | |
638 | * counting - only the first invoker will actually perform these actions. */ | |
639 | static int __init __sclp_vt220_init(int num_pages) | |
1da177e4 LT |
640 | { |
641 | void *page; | |
642 | int i; | |
59eb1ca7 | 643 | int rc; |
1da177e4 | 644 | |
ad211790 PO |
645 | sclp_vt220_init_count++; |
646 | if (sclp_vt220_init_count != 1) | |
1da177e4 | 647 | return 0; |
1da177e4 LT |
648 | spin_lock_init(&sclp_vt220_lock); |
649 | INIT_LIST_HEAD(&sclp_vt220_empty); | |
650 | INIT_LIST_HEAD(&sclp_vt220_outqueue); | |
1da177e4 | 651 | init_timer(&sclp_vt220_timer); |
092f7377 | 652 | tty_port_init(&sclp_vt220_port); |
1da177e4 LT |
653 | sclp_vt220_current_request = NULL; |
654 | sclp_vt220_buffered_chars = 0; | |
1da177e4 LT |
655 | sclp_vt220_flush_later = 0; |
656 | ||
657 | /* Allocate pages for output buffering */ | |
5c0792f6 | 658 | rc = -ENOMEM; |
5aaaf9f0 | 659 | for (i = 0; i < num_pages; i++) { |
5c0792f6 HC |
660 | page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
661 | if (!page) | |
ad211790 | 662 | goto out; |
5c0792f6 | 663 | list_add_tail(page, &sclp_vt220_empty); |
1da177e4 | 664 | } |
59eb1ca7 | 665 | rc = sclp_register(&sclp_vt220_register); |
ad211790 | 666 | out: |
59eb1ca7 | 667 | if (rc) { |
ad211790 PO |
668 | __sclp_vt220_free_pages(); |
669 | sclp_vt220_init_count--; | |
191c5f10 | 670 | tty_port_destroy(&sclp_vt220_port); |
59eb1ca7 CB |
671 | } |
672 | return rc; | |
1da177e4 LT |
673 | } |
674 | ||
b68e31d0 | 675 | static const struct tty_operations sclp_vt220_ops = { |
1da177e4 LT |
676 | .open = sclp_vt220_open, |
677 | .close = sclp_vt220_close, | |
678 | .write = sclp_vt220_write, | |
679 | .put_char = sclp_vt220_put_char, | |
680 | .flush_chars = sclp_vt220_flush_chars, | |
681 | .write_room = sclp_vt220_write_room, | |
682 | .chars_in_buffer = sclp_vt220_chars_in_buffer, | |
5aaaf9f0 | 683 | .flush_buffer = sclp_vt220_flush_buffer, |
1da177e4 LT |
684 | }; |
685 | ||
686 | /* | |
687 | * Register driver with SCLP and Linux and initialize internal tty structures. | |
688 | */ | |
5aaaf9f0 | 689 | static int __init sclp_vt220_tty_init(void) |
1da177e4 LT |
690 | { |
691 | struct tty_driver *driver; | |
692 | int rc; | |
693 | ||
694 | /* Note: we're not testing for CONSOLE_IS_SCLP here to preserve | |
695 | * symmetry between VM and LPAR systems regarding ttyS1. */ | |
696 | driver = alloc_tty_driver(1); | |
697 | if (!driver) | |
698 | return -ENOMEM; | |
ad211790 | 699 | rc = __sclp_vt220_init(MAX_KMEM_PAGES); |
5aaaf9f0 HC |
700 | if (rc) |
701 | goto out_driver; | |
1da177e4 | 702 | |
1da177e4 LT |
703 | driver->driver_name = SCLP_VT220_DRIVER_NAME; |
704 | driver->name = SCLP_VT220_DEVICE_NAME; | |
705 | driver->major = SCLP_VT220_MAJOR; | |
706 | driver->minor_start = SCLP_VT220_MINOR; | |
707 | driver->type = TTY_DRIVER_TYPE_SYSTEM; | |
708 | driver->subtype = SYSTEM_TYPE_TTY; | |
709 | driver->init_termios = tty_std_termios; | |
710 | driver->flags = TTY_DRIVER_REAL_RAW; | |
711 | tty_set_operations(driver, &sclp_vt220_ops); | |
b19e2ca7 | 712 | tty_port_link_device(&sclp_vt220_port, driver, 0); |
1da177e4 LT |
713 | |
714 | rc = tty_register_driver(driver); | |
a12c53f4 | 715 | if (rc) |
59eb1ca7 | 716 | goto out_init; |
e106e4ea PO |
717 | rc = sclp_register(&sclp_vt220_register_input); |
718 | if (rc) | |
719 | goto out_reg; | |
1da177e4 LT |
720 | sclp_vt220_driver = driver; |
721 | return 0; | |
1da177e4 | 722 | |
e106e4ea PO |
723 | out_reg: |
724 | tty_unregister_driver(driver); | |
5aaaf9f0 | 725 | out_init: |
ad211790 | 726 | __sclp_vt220_cleanup(); |
5aaaf9f0 HC |
727 | out_driver: |
728 | put_tty_driver(driver); | |
729 | return rc; | |
730 | } | |
731 | __initcall(sclp_vt220_tty_init); | |
1da177e4 | 732 | |
b3b59d33 HC |
733 | static void __sclp_vt220_flush_buffer(void) |
734 | { | |
735 | unsigned long flags; | |
736 | ||
737 | sclp_vt220_emit_current(); | |
738 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
739 | if (timer_pending(&sclp_vt220_timer)) | |
740 | del_timer(&sclp_vt220_timer); | |
62b74942 | 741 | while (sclp_vt220_queue_running) { |
b3b59d33 HC |
742 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
743 | sclp_sync_wait(); | |
744 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
745 | } | |
746 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
747 | } | |
748 | ||
62b74942 MH |
749 | /* |
750 | * Resume console: If there are cached messages, emit them. | |
751 | */ | |
752 | static void sclp_vt220_resume(void) | |
753 | { | |
754 | unsigned long flags; | |
755 | ||
756 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
757 | sclp_vt220_suspended = 0; | |
758 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
759 | sclp_vt220_emit_current(); | |
760 | } | |
761 | ||
762 | /* | |
763 | * Suspend console: Set suspend flag and flush console | |
764 | */ | |
765 | static void sclp_vt220_suspend(void) | |
766 | { | |
767 | unsigned long flags; | |
768 | ||
769 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
770 | sclp_vt220_suspended = 1; | |
771 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
772 | __sclp_vt220_flush_buffer(); | |
773 | } | |
774 | ||
775 | static void sclp_vt220_pm_event_fn(struct sclp_register *reg, | |
776 | enum sclp_pm_event sclp_pm_event) | |
777 | { | |
778 | switch (sclp_pm_event) { | |
779 | case SCLP_PM_EVENT_FREEZE: | |
780 | sclp_vt220_suspend(); | |
781 | break; | |
782 | case SCLP_PM_EVENT_RESTORE: | |
783 | case SCLP_PM_EVENT_THAW: | |
784 | sclp_vt220_resume(); | |
785 | break; | |
786 | } | |
787 | } | |
788 | ||
ac522b63 MH |
789 | #ifdef CONFIG_SCLP_VT220_CONSOLE |
790 | ||
791 | static void | |
792 | sclp_vt220_con_write(struct console *con, const char *buf, unsigned int count) | |
793 | { | |
794 | __sclp_vt220_write((const unsigned char *) buf, count, 1, 1, 0); | |
795 | } | |
796 | ||
797 | static struct tty_driver * | |
798 | sclp_vt220_con_device(struct console *c, int *index) | |
799 | { | |
800 | *index = 0; | |
801 | return sclp_vt220_driver; | |
802 | } | |
803 | ||
2332ce1a HS |
804 | static int |
805 | sclp_vt220_notify(struct notifier_block *self, | |
806 | unsigned long event, void *data) | |
1da177e4 LT |
807 | { |
808 | __sclp_vt220_flush_buffer(); | |
2332ce1a | 809 | return NOTIFY_OK; |
1da177e4 LT |
810 | } |
811 | ||
2332ce1a HS |
812 | static struct notifier_block on_panic_nb = { |
813 | .notifier_call = sclp_vt220_notify, | |
814 | .priority = 1, | |
815 | }; | |
816 | ||
817 | static struct notifier_block on_reboot_nb = { | |
818 | .notifier_call = sclp_vt220_notify, | |
819 | .priority = 1, | |
820 | }; | |
821 | ||
1da177e4 LT |
822 | /* Structure needed to register with printk */ |
823 | static struct console sclp_vt220_console = | |
824 | { | |
825 | .name = SCLP_VT220_CONSOLE_NAME, | |
826 | .write = sclp_vt220_con_write, | |
827 | .device = sclp_vt220_con_device, | |
1da177e4 LT |
828 | .flags = CON_PRINTBUFFER, |
829 | .index = SCLP_VT220_CONSOLE_INDEX | |
830 | }; | |
831 | ||
832 | static int __init | |
833 | sclp_vt220_con_init(void) | |
834 | { | |
835 | int rc; | |
836 | ||
25b41a7b | 837 | rc = __sclp_vt220_init(sclp_console_pages); |
1da177e4 LT |
838 | if (rc) |
839 | return rc; | |
840 | /* Attach linux console */ | |
2332ce1a HS |
841 | atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); |
842 | register_reboot_notifier(&on_reboot_nb); | |
1da177e4 LT |
843 | register_console(&sclp_vt220_console); |
844 | return 0; | |
845 | } | |
846 | ||
847 | console_initcall(sclp_vt220_con_init); | |
848 | #endif /* CONFIG_SCLP_VT220_CONSOLE */ | |
849 |