Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * drivers/s390/char/sclp_vt220.c |
| 3 | * SCLP VT220 terminal driver. |
| 4 | * |
| 5 | * S390 version |
Christian Borntraeger | 59eb1ca | 2008-02-09 18:24:33 +0100 | [diff] [blame] | 6 | * Copyright IBM Corp. 2003,2008 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | * Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com> |
| 8 | */ |
| 9 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/module.h> |
| 11 | #include <linux/spinlock.h> |
| 12 | #include <linux/list.h> |
| 13 | #include <linux/wait.h> |
| 14 | #include <linux/timer.h> |
| 15 | #include <linux/kernel.h> |
| 16 | #include <linux/tty.h> |
| 17 | #include <linux/tty_driver.h> |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 18 | #include <linux/tty_flip.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <linux/errno.h> |
| 20 | #include <linux/mm.h> |
| 21 | #include <linux/major.h> |
| 22 | #include <linux/console.h> |
| 23 | #include <linux/kdev_t.h> |
| 24 | #include <linux/bootmem.h> |
| 25 | #include <linux/interrupt.h> |
| 26 | #include <linux/init.h> |
| 27 | #include <asm/uaccess.h> |
| 28 | #include "sclp.h" |
| 29 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #define SCLP_VT220_MAJOR TTY_MAJOR |
| 31 | #define SCLP_VT220_MINOR 65 |
| 32 | #define SCLP_VT220_DRIVER_NAME "sclp_vt220" |
| 33 | #define SCLP_VT220_DEVICE_NAME "ttysclp" |
| 34 | #define SCLP_VT220_CONSOLE_NAME "ttyS" |
| 35 | #define SCLP_VT220_CONSOLE_INDEX 1 /* console=ttyS1 */ |
| 36 | #define SCLP_VT220_BUF_SIZE 80 |
| 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 | |
| 58 | /* The tty_struct that the kernel associated with us */ |
| 59 | static struct tty_struct *sclp_vt220_tty; |
| 60 | |
| 61 | /* Lock to protect internal data from concurrent access */ |
| 62 | static spinlock_t sclp_vt220_lock; |
| 63 | |
| 64 | /* List of empty pages to be used as write request buffers */ |
| 65 | static struct list_head sclp_vt220_empty; |
| 66 | |
| 67 | /* List of pending requests */ |
| 68 | static struct list_head sclp_vt220_outqueue; |
| 69 | |
| 70 | /* Number of requests in outqueue */ |
| 71 | static int sclp_vt220_outqueue_count; |
| 72 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | /* Timer used for delaying write requests to merge subsequent messages into |
| 74 | * a single buffer */ |
| 75 | static struct timer_list sclp_vt220_timer; |
| 76 | |
| 77 | /* Pointer to current request buffer which has been partially filled but not |
| 78 | * yet sent */ |
| 79 | static struct sclp_vt220_request *sclp_vt220_current_request; |
| 80 | |
| 81 | /* Number of characters in current request buffer */ |
| 82 | static int sclp_vt220_buffered_chars; |
| 83 | |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 84 | /* Counter controlling core driver initialization. */ |
| 85 | static int __initdata sclp_vt220_init_count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | |
| 87 | /* Flag indicating that sclp_vt220_current_request should really |
| 88 | * have been already queued but wasn't because the SCLP was processing |
| 89 | * another buffer */ |
| 90 | static int sclp_vt220_flush_later; |
| 91 | |
| 92 | static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf); |
| 93 | static int __sclp_vt220_emit(struct sclp_vt220_request *request); |
| 94 | static void sclp_vt220_emit_current(void); |
| 95 | |
| 96 | /* Registration structure for our interest in SCLP event buffers */ |
| 97 | static struct sclp_register sclp_vt220_register = { |
Stefan Haberland | 6d4740c | 2007-04-27 16:01:53 +0200 | [diff] [blame] | 98 | .send_mask = EVTYP_VT220MSG_MASK, |
| 99 | .receive_mask = EVTYP_VT220MSG_MASK, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | .state_change_fn = NULL, |
| 101 | .receiver_fn = sclp_vt220_receiver_fn |
| 102 | }; |
| 103 | |
| 104 | |
| 105 | /* |
| 106 | * Put provided request buffer back into queue and check emit pending |
| 107 | * buffers if necessary. |
| 108 | */ |
| 109 | static void |
| 110 | sclp_vt220_process_queue(struct sclp_vt220_request *request) |
| 111 | { |
| 112 | unsigned long flags; |
| 113 | void *page; |
| 114 | |
| 115 | do { |
| 116 | /* Put buffer back to list of empty buffers */ |
| 117 | page = request->sclp_req.sccb; |
| 118 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 119 | /* Move request from outqueue to empty queue */ |
| 120 | list_del(&request->list); |
| 121 | sclp_vt220_outqueue_count--; |
| 122 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); |
| 123 | /* Check if there is a pending buffer on the out queue. */ |
| 124 | request = NULL; |
| 125 | if (!list_empty(&sclp_vt220_outqueue)) |
| 126 | request = list_entry(sclp_vt220_outqueue.next, |
| 127 | struct sclp_vt220_request, list); |
| 128 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 129 | } while (request && __sclp_vt220_emit(request)); |
| 130 | if (request == NULL && sclp_vt220_flush_later) |
| 131 | sclp_vt220_emit_current(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | /* Check if the tty needs a wake up call */ |
| 133 | if (sclp_vt220_tty != NULL) { |
| 134 | tty_wakeup(sclp_vt220_tty); |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | #define SCLP_BUFFER_MAX_RETRY 1 |
| 139 | |
| 140 | /* |
| 141 | * Callback through which the result of a write request is reported by the |
| 142 | * SCLP. |
| 143 | */ |
| 144 | static void |
| 145 | sclp_vt220_callback(struct sclp_req *request, void *data) |
| 146 | { |
| 147 | struct sclp_vt220_request *vt220_request; |
| 148 | struct sclp_vt220_sccb *sccb; |
| 149 | |
| 150 | vt220_request = (struct sclp_vt220_request *) data; |
| 151 | if (request->status == SCLP_REQ_FAILED) { |
| 152 | sclp_vt220_process_queue(vt220_request); |
| 153 | return; |
| 154 | } |
| 155 | sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb; |
| 156 | |
| 157 | /* Check SCLP response code and choose suitable action */ |
| 158 | switch (sccb->header.response_code) { |
| 159 | case 0x0020 : |
| 160 | break; |
| 161 | |
| 162 | case 0x05f0: /* Target resource in improper state */ |
| 163 | break; |
| 164 | |
| 165 | case 0x0340: /* Contained SCLP equipment check */ |
| 166 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) |
| 167 | break; |
| 168 | /* Remove processed buffers and requeue rest */ |
| 169 | if (sclp_remove_processed((struct sccb_header *) sccb) > 0) { |
| 170 | /* Not all buffers were processed */ |
| 171 | sccb->header.response_code = 0x0000; |
| 172 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; |
| 173 | if (sclp_add_request(request) == 0) |
| 174 | return; |
| 175 | } |
| 176 | break; |
| 177 | |
| 178 | case 0x0040: /* SCLP equipment check */ |
| 179 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) |
| 180 | break; |
| 181 | sccb->header.response_code = 0x0000; |
| 182 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; |
| 183 | if (sclp_add_request(request) == 0) |
| 184 | return; |
| 185 | break; |
| 186 | |
| 187 | default: |
| 188 | break; |
| 189 | } |
| 190 | sclp_vt220_process_queue(vt220_request); |
| 191 | } |
| 192 | |
| 193 | /* |
| 194 | * Emit vt220 request buffer to SCLP. Return zero on success, non-zero |
| 195 | * otherwise. |
| 196 | */ |
| 197 | static int |
| 198 | __sclp_vt220_emit(struct sclp_vt220_request *request) |
| 199 | { |
Peter Oberparleiter | d082d3c | 2008-02-19 15:29:32 +0100 | [diff] [blame] | 200 | if (!(sclp_vt220_register.sclp_receive_mask & EVTYP_VT220MSG_MASK)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | request->sclp_req.status = SCLP_REQ_FAILED; |
| 202 | return -EIO; |
| 203 | } |
Heiko Carstens | ab14de6 | 2007-02-05 21:18:37 +0100 | [diff] [blame] | 204 | request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | request->sclp_req.status = SCLP_REQ_FILLED; |
| 206 | request->sclp_req.callback = sclp_vt220_callback; |
| 207 | request->sclp_req.callback_data = (void *) request; |
| 208 | |
| 209 | return sclp_add_request(&request->sclp_req); |
| 210 | } |
| 211 | |
| 212 | /* |
| 213 | * Queue and emit given request. |
| 214 | */ |
| 215 | static void |
| 216 | sclp_vt220_emit(struct sclp_vt220_request *request) |
| 217 | { |
| 218 | unsigned long flags; |
| 219 | int count; |
| 220 | |
| 221 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 222 | list_add_tail(&request->list, &sclp_vt220_outqueue); |
| 223 | count = sclp_vt220_outqueue_count++; |
| 224 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 225 | /* Emit only the first buffer immediately - callback takes care of |
| 226 | * the rest */ |
| 227 | if (count == 0 && __sclp_vt220_emit(request)) |
| 228 | sclp_vt220_process_queue(request); |
| 229 | } |
| 230 | |
| 231 | /* |
| 232 | * Queue and emit current request. Return zero on success, non-zero otherwise. |
| 233 | */ |
| 234 | static void |
| 235 | sclp_vt220_emit_current(void) |
| 236 | { |
| 237 | unsigned long flags; |
| 238 | struct sclp_vt220_request *request; |
| 239 | struct sclp_vt220_sccb *sccb; |
| 240 | |
| 241 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 242 | request = NULL; |
| 243 | if (sclp_vt220_current_request != NULL) { |
| 244 | sccb = (struct sclp_vt220_sccb *) |
| 245 | sclp_vt220_current_request->sclp_req.sccb; |
| 246 | /* Only emit buffers with content */ |
| 247 | if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) { |
| 248 | request = sclp_vt220_current_request; |
| 249 | sclp_vt220_current_request = NULL; |
| 250 | if (timer_pending(&sclp_vt220_timer)) |
| 251 | del_timer(&sclp_vt220_timer); |
| 252 | } |
| 253 | sclp_vt220_flush_later = 0; |
| 254 | } |
| 255 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 256 | if (request != NULL) |
| 257 | sclp_vt220_emit(request); |
| 258 | } |
| 259 | |
| 260 | #define SCLP_NORMAL_WRITE 0x00 |
| 261 | |
| 262 | /* |
| 263 | * Helper function to initialize a page with the sclp request structure. |
| 264 | */ |
| 265 | static struct sclp_vt220_request * |
| 266 | sclp_vt220_initialize_page(void *page) |
| 267 | { |
| 268 | struct sclp_vt220_request *request; |
| 269 | struct sclp_vt220_sccb *sccb; |
| 270 | |
| 271 | /* Place request structure at end of page */ |
| 272 | request = ((struct sclp_vt220_request *) |
| 273 | ((addr_t) page + PAGE_SIZE)) - 1; |
| 274 | request->retry_count = 0; |
| 275 | request->sclp_req.sccb = page; |
| 276 | /* SCCB goes at start of page */ |
| 277 | sccb = (struct sclp_vt220_sccb *) page; |
| 278 | memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb)); |
| 279 | sccb->header.length = sizeof(struct sclp_vt220_sccb); |
| 280 | sccb->header.function_code = SCLP_NORMAL_WRITE; |
| 281 | sccb->header.response_code = 0x0000; |
Stefan Haberland | 6d4740c | 2007-04-27 16:01:53 +0200 | [diff] [blame] | 282 | sccb->evbuf.type = EVTYP_VT220MSG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | sccb->evbuf.length = sizeof(struct evbuf_header); |
| 284 | |
| 285 | return request; |
| 286 | } |
| 287 | |
| 288 | static inline unsigned int |
| 289 | sclp_vt220_space_left(struct sclp_vt220_request *request) |
| 290 | { |
| 291 | struct sclp_vt220_sccb *sccb; |
| 292 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; |
| 293 | return PAGE_SIZE - sizeof(struct sclp_vt220_request) - |
| 294 | sccb->header.length; |
| 295 | } |
| 296 | |
| 297 | static inline unsigned int |
| 298 | sclp_vt220_chars_stored(struct sclp_vt220_request *request) |
| 299 | { |
| 300 | struct sclp_vt220_sccb *sccb; |
| 301 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; |
| 302 | return sccb->evbuf.length - sizeof(struct evbuf_header); |
| 303 | } |
| 304 | |
| 305 | /* |
| 306 | * Add msg to buffer associated with request. Return the number of characters |
| 307 | * added. |
| 308 | */ |
| 309 | static int |
| 310 | sclp_vt220_add_msg(struct sclp_vt220_request *request, |
| 311 | const unsigned char *msg, int count, int convertlf) |
| 312 | { |
| 313 | struct sclp_vt220_sccb *sccb; |
| 314 | void *buffer; |
| 315 | unsigned char c; |
| 316 | int from; |
| 317 | int to; |
| 318 | |
| 319 | if (count > sclp_vt220_space_left(request)) |
| 320 | count = sclp_vt220_space_left(request); |
| 321 | if (count <= 0) |
| 322 | return 0; |
| 323 | |
| 324 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; |
| 325 | buffer = (void *) ((addr_t) sccb + sccb->header.length); |
| 326 | |
| 327 | if (convertlf) { |
| 328 | /* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/ |
| 329 | for (from=0, to=0; |
| 330 | (from < count) && (to < sclp_vt220_space_left(request)); |
| 331 | from++) { |
| 332 | /* Retrieve character */ |
| 333 | c = msg[from]; |
| 334 | /* Perform conversion */ |
| 335 | if (c == 0x0a) { |
| 336 | if (to + 1 < sclp_vt220_space_left(request)) { |
| 337 | ((unsigned char *) buffer)[to++] = c; |
| 338 | ((unsigned char *) buffer)[to++] = 0x0d; |
| 339 | } else |
| 340 | break; |
| 341 | |
| 342 | } else |
| 343 | ((unsigned char *) buffer)[to++] = c; |
| 344 | } |
| 345 | sccb->header.length += to; |
| 346 | sccb->evbuf.length += to; |
| 347 | return from; |
| 348 | } else { |
| 349 | memcpy(buffer, (const void *) msg, count); |
| 350 | sccb->header.length += count; |
| 351 | sccb->evbuf.length += count; |
| 352 | return count; |
| 353 | } |
| 354 | } |
| 355 | |
| 356 | /* |
| 357 | * Emit buffer after having waited long enough for more data to arrive. |
| 358 | */ |
| 359 | static void |
| 360 | sclp_vt220_timeout(unsigned long data) |
| 361 | { |
| 362 | sclp_vt220_emit_current(); |
| 363 | } |
| 364 | |
Christian Borntraeger | fa331ff | 2008-03-05 12:37:12 +0100 | [diff] [blame] | 365 | #define BUFFER_MAX_DELAY HZ/20 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | |
| 367 | /* |
| 368 | * Internal implementation of the write function. Write COUNT bytes of data |
| 369 | * from memory at BUF |
| 370 | * to the SCLP interface. In case that the data does not fit into the current |
| 371 | * write buffer, emit the current one and allocate a new one. If there are no |
| 372 | * more empty buffers available, wait until one gets emptied. If DO_SCHEDULE |
| 373 | * is non-zero, the buffer will be scheduled for emitting after a timeout - |
| 374 | * otherwise the user has to explicitly call the flush function. |
| 375 | * A non-zero CONVERTLF parameter indicates that 0x0a characters in the message |
| 376 | * buffer should be converted to 0x0a 0x0d. After completion, return the number |
| 377 | * of bytes written. |
| 378 | */ |
| 379 | static int |
| 380 | __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule, |
Heiko Carstens | d4820e4 | 2008-05-30 10:03:30 +0200 | [diff] [blame] | 381 | int convertlf, int may_fail) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | { |
| 383 | unsigned long flags; |
| 384 | void *page; |
| 385 | int written; |
| 386 | int overall_written; |
| 387 | |
| 388 | if (count <= 0) |
| 389 | return 0; |
| 390 | overall_written = 0; |
| 391 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 392 | do { |
Heiko Carstens | d4820e4 | 2008-05-30 10:03:30 +0200 | [diff] [blame] | 393 | /* Create an sclp output buffer if none exists yet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | if (sclp_vt220_current_request == NULL) { |
| 395 | while (list_empty(&sclp_vt220_empty)) { |
Heiko Carstens | d1e2337 | 2008-04-17 07:46:02 +0200 | [diff] [blame] | 396 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
Heiko Carstens | d4820e4 | 2008-05-30 10:03:30 +0200 | [diff] [blame] | 397 | if (may_fail) |
| 398 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | else |
Heiko Carstens | d4820e4 | 2008-05-30 10:03:30 +0200 | [diff] [blame] | 400 | sclp_sync_wait(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 402 | } |
| 403 | page = (void *) sclp_vt220_empty.next; |
| 404 | list_del((struct list_head *) page); |
| 405 | sclp_vt220_current_request = |
| 406 | sclp_vt220_initialize_page(page); |
| 407 | } |
| 408 | /* Try to write the string to the current request buffer */ |
| 409 | written = sclp_vt220_add_msg(sclp_vt220_current_request, |
| 410 | buf, count, convertlf); |
| 411 | overall_written += written; |
| 412 | if (written == count) |
| 413 | break; |
| 414 | /* |
| 415 | * Not all characters could be written to the current |
| 416 | * output buffer. Emit the buffer, create a new buffer |
| 417 | * and then output the rest of the string. |
| 418 | */ |
| 419 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 420 | sclp_vt220_emit_current(); |
| 421 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 422 | buf += written; |
| 423 | count -= written; |
| 424 | } while (count > 0); |
| 425 | /* Setup timer to output current console buffer after some time */ |
| 426 | if (sclp_vt220_current_request != NULL && |
| 427 | !timer_pending(&sclp_vt220_timer) && do_schedule) { |
| 428 | sclp_vt220_timer.function = sclp_vt220_timeout; |
| 429 | sclp_vt220_timer.data = 0UL; |
| 430 | sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY; |
| 431 | add_timer(&sclp_vt220_timer); |
| 432 | } |
| 433 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
Heiko Carstens | d4820e4 | 2008-05-30 10:03:30 +0200 | [diff] [blame] | 434 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 435 | return overall_written; |
| 436 | } |
| 437 | |
| 438 | /* |
| 439 | * This routine is called by the kernel to write a series of |
| 440 | * characters to the tty device. The characters may come from |
| 441 | * user space or kernel space. This routine will return the |
| 442 | * number of characters actually accepted for writing. |
| 443 | */ |
| 444 | static int |
| 445 | sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count) |
| 446 | { |
Heiko Carstens | d1e2337 | 2008-04-17 07:46:02 +0200 | [diff] [blame] | 447 | return __sclp_vt220_write(buf, count, 1, 0, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | } |
| 449 | |
| 450 | #define SCLP_VT220_SESSION_ENDED 0x01 |
| 451 | #define SCLP_VT220_SESSION_STARTED 0x80 |
| 452 | #define SCLP_VT220_SESSION_DATA 0x00 |
| 453 | |
| 454 | /* |
| 455 | * Called by the SCLP to report incoming event buffers. |
| 456 | */ |
| 457 | static void |
| 458 | sclp_vt220_receiver_fn(struct evbuf_header *evbuf) |
| 459 | { |
| 460 | char *buffer; |
| 461 | unsigned int count; |
| 462 | |
| 463 | /* Ignore input if device is not open */ |
| 464 | if (sclp_vt220_tty == NULL) |
| 465 | return; |
| 466 | |
| 467 | buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header)); |
| 468 | count = evbuf->length - sizeof(struct evbuf_header); |
| 469 | |
| 470 | switch (*buffer) { |
| 471 | case SCLP_VT220_SESSION_ENDED: |
| 472 | case SCLP_VT220_SESSION_STARTED: |
| 473 | break; |
| 474 | case SCLP_VT220_SESSION_DATA: |
| 475 | /* Send input to line discipline */ |
| 476 | buffer++; |
| 477 | count--; |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 478 | tty_insert_flip_string(sclp_vt220_tty, buffer, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | tty_flip_buffer_push(sclp_vt220_tty); |
| 480 | break; |
| 481 | } |
| 482 | } |
| 483 | |
| 484 | /* |
| 485 | * This routine is called when a particular tty device is opened. |
| 486 | */ |
| 487 | static int |
| 488 | sclp_vt220_open(struct tty_struct *tty, struct file *filp) |
| 489 | { |
| 490 | if (tty->count == 1) { |
| 491 | sclp_vt220_tty = tty; |
| 492 | tty->driver_data = kmalloc(SCLP_VT220_BUF_SIZE, GFP_KERNEL); |
| 493 | if (tty->driver_data == NULL) |
| 494 | return -ENOMEM; |
| 495 | tty->low_latency = 0; |
| 496 | } |
| 497 | return 0; |
| 498 | } |
| 499 | |
| 500 | /* |
| 501 | * This routine is called when a particular tty device is closed. |
| 502 | */ |
| 503 | static void |
| 504 | sclp_vt220_close(struct tty_struct *tty, struct file *filp) |
| 505 | { |
| 506 | if (tty->count == 1) { |
| 507 | sclp_vt220_tty = NULL; |
| 508 | kfree(tty->driver_data); |
| 509 | tty->driver_data = NULL; |
| 510 | } |
| 511 | } |
| 512 | |
| 513 | /* |
| 514 | * This routine is called by the kernel to write a single |
| 515 | * character to the tty device. If the kernel uses this routine, |
| 516 | * it must call the flush_chars() routine (if defined) when it is |
| 517 | * done stuffing characters into the driver. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | */ |
Alan Cox | 9e7c9a1 | 2008-04-30 00:54:00 -0700 | [diff] [blame] | 519 | static int |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch) |
| 521 | { |
Heiko Carstens | d4820e4 | 2008-05-30 10:03:30 +0200 | [diff] [blame] | 522 | return __sclp_vt220_write(&ch, 1, 0, 0, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | } |
| 524 | |
| 525 | /* |
| 526 | * This routine is called by the kernel after it has written a |
| 527 | * series of characters to the tty device using put_char(). |
| 528 | */ |
| 529 | static void |
| 530 | sclp_vt220_flush_chars(struct tty_struct *tty) |
| 531 | { |
| 532 | if (sclp_vt220_outqueue_count == 0) |
| 533 | sclp_vt220_emit_current(); |
| 534 | else |
| 535 | sclp_vt220_flush_later = 1; |
| 536 | } |
| 537 | |
| 538 | /* |
| 539 | * This routine returns the numbers of characters the tty driver |
| 540 | * will accept for queuing to be written. This number is subject |
| 541 | * to change as output buffers get emptied, or if the output flow |
| 542 | * control is acted. |
| 543 | */ |
| 544 | static int |
| 545 | sclp_vt220_write_room(struct tty_struct *tty) |
| 546 | { |
| 547 | unsigned long flags; |
| 548 | struct list_head *l; |
| 549 | int count; |
| 550 | |
| 551 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 552 | count = 0; |
| 553 | if (sclp_vt220_current_request != NULL) |
| 554 | count = sclp_vt220_space_left(sclp_vt220_current_request); |
| 555 | list_for_each(l, &sclp_vt220_empty) |
| 556 | count += SCLP_VT220_MAX_CHARS_PER_BUFFER; |
| 557 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 558 | return count; |
| 559 | } |
| 560 | |
| 561 | /* |
| 562 | * Return number of buffered chars. |
| 563 | */ |
| 564 | static int |
| 565 | sclp_vt220_chars_in_buffer(struct tty_struct *tty) |
| 566 | { |
| 567 | unsigned long flags; |
| 568 | struct list_head *l; |
| 569 | struct sclp_vt220_request *r; |
| 570 | int count; |
| 571 | |
| 572 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 573 | count = 0; |
| 574 | if (sclp_vt220_current_request != NULL) |
| 575 | count = sclp_vt220_chars_stored(sclp_vt220_current_request); |
| 576 | list_for_each(l, &sclp_vt220_outqueue) { |
| 577 | r = list_entry(l, struct sclp_vt220_request, list); |
| 578 | count += sclp_vt220_chars_stored(r); |
| 579 | } |
| 580 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 581 | return count; |
| 582 | } |
| 583 | |
| 584 | static void |
| 585 | __sclp_vt220_flush_buffer(void) |
| 586 | { |
| 587 | unsigned long flags; |
| 588 | |
| 589 | sclp_vt220_emit_current(); |
| 590 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 591 | if (timer_pending(&sclp_vt220_timer)) |
| 592 | del_timer(&sclp_vt220_timer); |
| 593 | while (sclp_vt220_outqueue_count > 0) { |
| 594 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 595 | sclp_sync_wait(); |
| 596 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
| 597 | } |
| 598 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * Pass on all buffers to the hardware. Return only when there are no more |
| 603 | * buffers pending. |
| 604 | */ |
| 605 | static void |
| 606 | sclp_vt220_flush_buffer(struct tty_struct *tty) |
| 607 | { |
| 608 | sclp_vt220_emit_current(); |
| 609 | } |
| 610 | |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 611 | /* Release allocated pages. */ |
| 612 | static void __init __sclp_vt220_free_pages(void) |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 613 | { |
| 614 | struct list_head *page, *p; |
| 615 | |
| 616 | list_for_each_safe(page, p, &sclp_vt220_empty) { |
| 617 | list_del(page); |
| 618 | if (slab_is_available()) |
| 619 | free_page((unsigned long) page); |
| 620 | else |
| 621 | free_bootmem((unsigned long) page, PAGE_SIZE); |
| 622 | } |
| 623 | } |
| 624 | |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 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(); |
| 634 | } |
| 635 | |
| 636 | /* Allocate buffer pages and register with sclp core. Controlled by init |
| 637 | * counting - only the first invoker will actually perform these actions. */ |
| 638 | static int __init __sclp_vt220_init(int num_pages) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | { |
| 640 | void *page; |
| 641 | int i; |
Christian Borntraeger | 59eb1ca | 2008-02-09 18:24:33 +0100 | [diff] [blame] | 642 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 643 | |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 644 | sclp_vt220_init_count++; |
| 645 | if (sclp_vt220_init_count != 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 646 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | spin_lock_init(&sclp_vt220_lock); |
| 648 | INIT_LIST_HEAD(&sclp_vt220_empty); |
| 649 | INIT_LIST_HEAD(&sclp_vt220_outqueue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 650 | init_timer(&sclp_vt220_timer); |
| 651 | sclp_vt220_current_request = NULL; |
| 652 | sclp_vt220_buffered_chars = 0; |
| 653 | sclp_vt220_outqueue_count = 0; |
| 654 | sclp_vt220_tty = NULL; |
| 655 | sclp_vt220_flush_later = 0; |
| 656 | |
| 657 | /* Allocate pages for output buffering */ |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 658 | for (i = 0; i < num_pages; i++) { |
| 659 | if (slab_is_available()) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 660 | page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 661 | else |
| 662 | page = alloc_bootmem_low_pages(PAGE_SIZE); |
| 663 | if (!page) { |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 664 | rc = -ENOMEM; |
| 665 | goto out; |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 666 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); |
| 668 | } |
Christian Borntraeger | 59eb1ca | 2008-02-09 18:24:33 +0100 | [diff] [blame] | 669 | rc = sclp_register(&sclp_vt220_register); |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 670 | out: |
Christian Borntraeger | 59eb1ca | 2008-02-09 18:24:33 +0100 | [diff] [blame] | 671 | if (rc) { |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 672 | __sclp_vt220_free_pages(); |
| 673 | sclp_vt220_init_count--; |
Christian Borntraeger | 59eb1ca | 2008-02-09 18:24:33 +0100 | [diff] [blame] | 674 | } |
| 675 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | } |
| 677 | |
Jeff Dike | b68e31d | 2006-10-02 02:17:18 -0700 | [diff] [blame] | 678 | static const struct tty_operations sclp_vt220_ops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | .open = sclp_vt220_open, |
| 680 | .close = sclp_vt220_close, |
| 681 | .write = sclp_vt220_write, |
| 682 | .put_char = sclp_vt220_put_char, |
| 683 | .flush_chars = sclp_vt220_flush_chars, |
| 684 | .write_room = sclp_vt220_write_room, |
| 685 | .chars_in_buffer = sclp_vt220_chars_in_buffer, |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 686 | .flush_buffer = sclp_vt220_flush_buffer, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 687 | }; |
| 688 | |
| 689 | /* |
| 690 | * Register driver with SCLP and Linux and initialize internal tty structures. |
| 691 | */ |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 692 | static int __init sclp_vt220_tty_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 693 | { |
| 694 | struct tty_driver *driver; |
| 695 | int rc; |
| 696 | |
| 697 | /* Note: we're not testing for CONSOLE_IS_SCLP here to preserve |
| 698 | * symmetry between VM and LPAR systems regarding ttyS1. */ |
| 699 | driver = alloc_tty_driver(1); |
| 700 | if (!driver) |
| 701 | return -ENOMEM; |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 702 | rc = __sclp_vt220_init(MAX_KMEM_PAGES); |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 703 | if (rc) |
| 704 | goto out_driver; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | |
| 706 | driver->owner = THIS_MODULE; |
| 707 | driver->driver_name = SCLP_VT220_DRIVER_NAME; |
| 708 | driver->name = SCLP_VT220_DEVICE_NAME; |
| 709 | driver->major = SCLP_VT220_MAJOR; |
| 710 | driver->minor_start = SCLP_VT220_MINOR; |
| 711 | driver->type = TTY_DRIVER_TYPE_SYSTEM; |
| 712 | driver->subtype = SYSTEM_TYPE_TTY; |
| 713 | driver->init_termios = tty_std_termios; |
| 714 | driver->flags = TTY_DRIVER_REAL_RAW; |
| 715 | tty_set_operations(driver, &sclp_vt220_ops); |
| 716 | |
| 717 | rc = tty_register_driver(driver); |
Martin Schwidefsky | a12c53f | 2008-07-14 09:59:28 +0200 | [diff] [blame] | 718 | if (rc) |
Christian Borntraeger | 59eb1ca | 2008-02-09 18:24:33 +0100 | [diff] [blame] | 719 | goto out_init; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | sclp_vt220_driver = driver; |
| 721 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 723 | out_init: |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 724 | __sclp_vt220_cleanup(); |
Heiko Carstens | 5aaaf9f | 2007-07-27 12:29:22 +0200 | [diff] [blame] | 725 | out_driver: |
| 726 | put_tty_driver(driver); |
| 727 | return rc; |
| 728 | } |
| 729 | __initcall(sclp_vt220_tty_init); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | |
| 731 | #ifdef CONFIG_SCLP_VT220_CONSOLE |
| 732 | |
| 733 | static void |
| 734 | sclp_vt220_con_write(struct console *con, const char *buf, unsigned int count) |
| 735 | { |
Heiko Carstens | d1e2337 | 2008-04-17 07:46:02 +0200 | [diff] [blame] | 736 | __sclp_vt220_write((const unsigned char *) buf, count, 1, 1, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | } |
| 738 | |
| 739 | static struct tty_driver * |
| 740 | sclp_vt220_con_device(struct console *c, int *index) |
| 741 | { |
| 742 | *index = 0; |
| 743 | return sclp_vt220_driver; |
| 744 | } |
| 745 | |
| 746 | /* |
| 747 | * This routine is called from panic when the kernel is going to give up. |
| 748 | * We have to make sure that all buffers will be flushed to the SCLP. |
| 749 | * Note that this function may be called from within an interrupt context. |
| 750 | */ |
| 751 | static void |
| 752 | sclp_vt220_con_unblank(void) |
| 753 | { |
| 754 | __sclp_vt220_flush_buffer(); |
| 755 | } |
| 756 | |
| 757 | /* Structure needed to register with printk */ |
| 758 | static struct console sclp_vt220_console = |
| 759 | { |
| 760 | .name = SCLP_VT220_CONSOLE_NAME, |
| 761 | .write = sclp_vt220_con_write, |
| 762 | .device = sclp_vt220_con_device, |
| 763 | .unblank = sclp_vt220_con_unblank, |
| 764 | .flags = CON_PRINTBUFFER, |
| 765 | .index = SCLP_VT220_CONSOLE_INDEX |
| 766 | }; |
| 767 | |
| 768 | static int __init |
| 769 | sclp_vt220_con_init(void) |
| 770 | { |
| 771 | int rc; |
| 772 | |
| 773 | if (!CONSOLE_IS_SCLP) |
| 774 | return 0; |
Peter Oberparleiter | ad21179 | 2008-07-14 09:59:07 +0200 | [diff] [blame] | 775 | rc = __sclp_vt220_init(MAX_CONSOLE_PAGES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 776 | if (rc) |
| 777 | return rc; |
| 778 | /* Attach linux console */ |
| 779 | register_console(&sclp_vt220_console); |
| 780 | return 0; |
| 781 | } |
| 782 | |
| 783 | console_initcall(sclp_vt220_con_init); |
| 784 | #endif /* CONFIG_SCLP_VT220_CONSOLE */ |
| 785 | |