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e1eaea46 AC |
1 | /* |
2 | * n_gsm.c GSM 0710 tty multiplexor | |
3 | * Copyright (c) 2009/10 Intel Corporation | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
17 | * | |
18 | * * THIS IS A DEVELOPMENT SNAPSHOT IT IS NOT A FINAL RELEASE * | |
19 | * | |
20 | * TO DO: | |
21 | * Mostly done: ioctls for setting modes/timing | |
5f9a31d6 | 22 | * Partly done: hooks so you can pull off frames to non tty devs |
e1eaea46 AC |
23 | * Restart DLCI 0 when it closes ? |
24 | * Test basic encoding | |
25 | * Improve the tx engine | |
26 | * Resolve tx side locking by adding a queue_head and routing | |
27 | * all control traffic via it | |
28 | * General tidy/document | |
29 | * Review the locking/move to refcounts more (mux now moved to an | |
30 | * alloc/free model ready) | |
31 | * Use newest tty open/close port helpers and install hooks | |
32 | * What to do about power functions ? | |
33 | * Termios setting and negotiation | |
34 | * Do we need a 'which mux are you' ioctl to correlate mux and tty sets | |
35 | * | |
36 | */ | |
37 | ||
38 | #include <linux/types.h> | |
39 | #include <linux/major.h> | |
40 | #include <linux/errno.h> | |
41 | #include <linux/signal.h> | |
42 | #include <linux/fcntl.h> | |
43 | #include <linux/sched.h> | |
44 | #include <linux/interrupt.h> | |
45 | #include <linux/tty.h> | |
e1eaea46 AC |
46 | #include <linux/ctype.h> |
47 | #include <linux/mm.h> | |
48 | #include <linux/string.h> | |
49 | #include <linux/slab.h> | |
50 | #include <linux/poll.h> | |
51 | #include <linux/bitops.h> | |
52 | #include <linux/file.h> | |
53 | #include <linux/uaccess.h> | |
54 | #include <linux/module.h> | |
55 | #include <linux/timer.h> | |
56 | #include <linux/tty_flip.h> | |
57 | #include <linux/tty_driver.h> | |
58 | #include <linux/serial.h> | |
59 | #include <linux/kfifo.h> | |
60 | #include <linux/skbuff.h> | |
bcd5abe2 RG |
61 | #include <net/arp.h> |
62 | #include <linux/ip.h> | |
63 | #include <linux/netdevice.h> | |
64 | #include <linux/etherdevice.h> | |
e1eaea46 AC |
65 | #include <linux/gsmmux.h> |
66 | ||
67 | static int debug; | |
68 | module_param(debug, int, 0600); | |
69 | ||
70 | #define T1 (HZ/10) | |
71 | #define T2 (HZ/3) | |
72 | #define N2 3 | |
73 | ||
74 | /* Use long timers for testing at low speed with debug on */ | |
75 | #ifdef DEBUG_TIMING | |
76 | #define T1 HZ | |
77 | #define T2 (2 * HZ) | |
78 | #endif | |
79 | ||
5f9a31d6 | 80 | /* |
25985edc | 81 | * Semi-arbitrary buffer size limits. 0710 is normally run with 32-64 byte |
5f9a31d6 AC |
82 | * limits so this is plenty |
83 | */ | |
bcd5abe2 RG |
84 | #define MAX_MRU 1500 |
85 | #define MAX_MTU 1500 | |
86 | #define GSM_NET_TX_TIMEOUT (HZ*10) | |
87 | ||
88 | /** | |
89 | * struct gsm_mux_net - network interface | |
90 | * @struct gsm_dlci* dlci | |
91 | * @struct net_device_stats stats; | |
92 | * | |
93 | * Created when net interface is initialized. | |
94 | **/ | |
95 | struct gsm_mux_net { | |
96 | struct kref ref; | |
97 | struct gsm_dlci *dlci; | |
98 | struct net_device_stats stats; | |
99 | }; | |
100 | ||
101 | #define STATS(net) (((struct gsm_mux_net *)netdev_priv(net))->stats) | |
e1eaea46 AC |
102 | |
103 | /* | |
104 | * Each block of data we have queued to go out is in the form of | |
25985edc | 105 | * a gsm_msg which holds everything we need in a link layer independent |
e1eaea46 AC |
106 | * format |
107 | */ | |
108 | ||
109 | struct gsm_msg { | |
110 | struct gsm_msg *next; | |
111 | u8 addr; /* DLCI address + flags */ | |
112 | u8 ctrl; /* Control byte + flags */ | |
113 | unsigned int len; /* Length of data block (can be zero) */ | |
114 | unsigned char *data; /* Points into buffer but not at the start */ | |
115 | unsigned char buffer[0]; | |
116 | }; | |
117 | ||
118 | /* | |
119 | * Each active data link has a gsm_dlci structure associated which ties | |
120 | * the link layer to an optional tty (if the tty side is open). To avoid | |
121 | * complexity right now these are only ever freed up when the mux is | |
122 | * shut down. | |
123 | * | |
124 | * At the moment we don't free DLCI objects until the mux is torn down | |
125 | * this avoid object life time issues but might be worth review later. | |
126 | */ | |
127 | ||
128 | struct gsm_dlci { | |
129 | struct gsm_mux *gsm; | |
130 | int addr; | |
131 | int state; | |
132 | #define DLCI_CLOSED 0 | |
133 | #define DLCI_OPENING 1 /* Sending SABM not seen UA */ | |
134 | #define DLCI_OPEN 2 /* SABM/UA complete */ | |
135 | #define DLCI_CLOSING 3 /* Sending DISC not seen UA/DM */ | |
6ab8fba7 | 136 | struct kref ref; /* freed from port or mux close */ |
bcd5abe2 | 137 | struct mutex mutex; |
e1eaea46 AC |
138 | |
139 | /* Link layer */ | |
140 | spinlock_t lock; /* Protects the internal state */ | |
141 | struct timer_list t1; /* Retransmit timer for SABM and UA */ | |
142 | int retries; | |
143 | /* Uplink tty if active */ | |
144 | struct tty_port port; /* The tty bound to this DLCI if there is one */ | |
145 | struct kfifo *fifo; /* Queue fifo for the DLCI */ | |
146 | struct kfifo _fifo; /* For new fifo API porting only */ | |
147 | int adaption; /* Adaption layer in use */ | |
bcd5abe2 | 148 | int prev_adaption; |
e1eaea46 AC |
149 | u32 modem_rx; /* Our incoming virtual modem lines */ |
150 | u32 modem_tx; /* Our outgoing modem lines */ | |
151 | int dead; /* Refuse re-open */ | |
152 | /* Flow control */ | |
153 | int throttled; /* Private copy of throttle state */ | |
154 | int constipated; /* Throttle status for outgoing */ | |
155 | /* Packetised I/O */ | |
156 | struct sk_buff *skb; /* Frame being sent */ | |
157 | struct sk_buff_head skb_list; /* Queued frames */ | |
158 | /* Data handling callback */ | |
159 | void (*data)(struct gsm_dlci *dlci, u8 *data, int len); | |
bcd5abe2 RG |
160 | void (*prev_data)(struct gsm_dlci *dlci, u8 *data, int len); |
161 | struct net_device *net; /* network interface, if created */ | |
e1eaea46 AC |
162 | }; |
163 | ||
164 | /* DLCI 0, 62/63 are special or reseved see gsmtty_open */ | |
165 | ||
166 | #define NUM_DLCI 64 | |
167 | ||
168 | /* | |
169 | * DLCI 0 is used to pass control blocks out of band of the data | |
170 | * flow (and with a higher link priority). One command can be outstanding | |
171 | * at a time and we use this structure to manage them. They are created | |
172 | * and destroyed by the user context, and updated by the receive paths | |
173 | * and timers | |
174 | */ | |
175 | ||
176 | struct gsm_control { | |
177 | u8 cmd; /* Command we are issuing */ | |
178 | u8 *data; /* Data for the command in case we retransmit */ | |
179 | int len; /* Length of block for retransmission */ | |
180 | int done; /* Done flag */ | |
181 | int error; /* Error if any */ | |
182 | }; | |
183 | ||
184 | /* | |
185 | * Each GSM mux we have is represented by this structure. If we are | |
186 | * operating as an ldisc then we use this structure as our ldisc | |
187 | * state. We need to sort out lifetimes and locking with respect | |
188 | * to the gsm mux array. For now we don't free DLCI objects that | |
189 | * have been instantiated until the mux itself is terminated. | |
190 | * | |
191 | * To consider further: tty open versus mux shutdown. | |
192 | */ | |
193 | ||
194 | struct gsm_mux { | |
195 | struct tty_struct *tty; /* The tty our ldisc is bound to */ | |
196 | spinlock_t lock; | |
d50f6dca | 197 | unsigned int num; |
6ab8fba7 | 198 | struct kref ref; |
e1eaea46 AC |
199 | |
200 | /* Events on the GSM channel */ | |
201 | wait_queue_head_t event; | |
202 | ||
203 | /* Bits for GSM mode decoding */ | |
204 | ||
205 | /* Framing Layer */ | |
206 | unsigned char *buf; | |
207 | int state; | |
208 | #define GSM_SEARCH 0 | |
209 | #define GSM_START 1 | |
210 | #define GSM_ADDRESS 2 | |
211 | #define GSM_CONTROL 3 | |
212 | #define GSM_LEN 4 | |
213 | #define GSM_DATA 5 | |
214 | #define GSM_FCS 6 | |
215 | #define GSM_OVERRUN 7 | |
c2f2f000 AC |
216 | #define GSM_LEN0 8 |
217 | #define GSM_LEN1 9 | |
218 | #define GSM_SSOF 10 | |
e1eaea46 AC |
219 | unsigned int len; |
220 | unsigned int address; | |
221 | unsigned int count; | |
222 | int escape; | |
223 | int encoding; | |
224 | u8 control; | |
225 | u8 fcs; | |
c2f2f000 | 226 | u8 received_fcs; |
e1eaea46 AC |
227 | u8 *txframe; /* TX framing buffer */ |
228 | ||
229 | /* Methods for the receiver side */ | |
230 | void (*receive)(struct gsm_mux *gsm, u8 ch); | |
231 | void (*error)(struct gsm_mux *gsm, u8 ch, u8 flag); | |
232 | /* And transmit side */ | |
233 | int (*output)(struct gsm_mux *mux, u8 *data, int len); | |
234 | ||
235 | /* Link Layer */ | |
236 | unsigned int mru; | |
237 | unsigned int mtu; | |
238 | int initiator; /* Did we initiate connection */ | |
239 | int dead; /* Has the mux been shut down */ | |
240 | struct gsm_dlci *dlci[NUM_DLCI]; | |
241 | int constipated; /* Asked by remote to shut up */ | |
242 | ||
243 | spinlock_t tx_lock; | |
244 | unsigned int tx_bytes; /* TX data outstanding */ | |
245 | #define TX_THRESH_HI 8192 | |
246 | #define TX_THRESH_LO 2048 | |
247 | struct gsm_msg *tx_head; /* Pending data packets */ | |
248 | struct gsm_msg *tx_tail; | |
249 | ||
250 | /* Control messages */ | |
251 | struct timer_list t2_timer; /* Retransmit timer for commands */ | |
252 | int cretries; /* Command retry counter */ | |
253 | struct gsm_control *pending_cmd;/* Our current pending command */ | |
254 | spinlock_t control_lock; /* Protects the pending command */ | |
255 | ||
256 | /* Configuration */ | |
257 | int adaption; /* 1 or 2 supported */ | |
258 | u8 ftype; /* UI or UIH */ | |
259 | int t1, t2; /* Timers in 1/100th of a sec */ | |
260 | int n2; /* Retry count */ | |
261 | ||
262 | /* Statistics (not currently exposed) */ | |
263 | unsigned long bad_fcs; | |
264 | unsigned long malformed; | |
265 | unsigned long io_error; | |
266 | unsigned long bad_size; | |
267 | unsigned long unsupported; | |
268 | }; | |
269 | ||
270 | ||
271 | /* | |
272 | * Mux objects - needed so that we can translate a tty index into the | |
273 | * relevant mux and DLCI. | |
274 | */ | |
275 | ||
276 | #define MAX_MUX 4 /* 256 minors */ | |
277 | static struct gsm_mux *gsm_mux[MAX_MUX]; /* GSM muxes */ | |
278 | static spinlock_t gsm_mux_lock; | |
279 | ||
d50f6dca RG |
280 | static struct tty_driver *gsm_tty_driver; |
281 | ||
e1eaea46 AC |
282 | /* |
283 | * This section of the driver logic implements the GSM encodings | |
284 | * both the basic and the 'advanced'. Reliable transport is not | |
285 | * supported. | |
286 | */ | |
287 | ||
288 | #define CR 0x02 | |
289 | #define EA 0x01 | |
290 | #define PF 0x10 | |
291 | ||
292 | /* I is special: the rest are ..*/ | |
293 | #define RR 0x01 | |
294 | #define UI 0x03 | |
295 | #define RNR 0x05 | |
296 | #define REJ 0x09 | |
297 | #define DM 0x0F | |
298 | #define SABM 0x2F | |
299 | #define DISC 0x43 | |
300 | #define UA 0x63 | |
301 | #define UIH 0xEF | |
302 | ||
303 | /* Channel commands */ | |
304 | #define CMD_NSC 0x09 | |
305 | #define CMD_TEST 0x11 | |
306 | #define CMD_PSC 0x21 | |
307 | #define CMD_RLS 0x29 | |
308 | #define CMD_FCOFF 0x31 | |
309 | #define CMD_PN 0x41 | |
310 | #define CMD_RPN 0x49 | |
311 | #define CMD_FCON 0x51 | |
312 | #define CMD_CLD 0x61 | |
313 | #define CMD_SNC 0x69 | |
314 | #define CMD_MSC 0x71 | |
315 | ||
316 | /* Virtual modem bits */ | |
317 | #define MDM_FC 0x01 | |
318 | #define MDM_RTC 0x02 | |
319 | #define MDM_RTR 0x04 | |
320 | #define MDM_IC 0x20 | |
321 | #define MDM_DV 0x40 | |
322 | ||
323 | #define GSM0_SOF 0xF9 | |
5f9a31d6 | 324 | #define GSM1_SOF 0x7E |
e1eaea46 AC |
325 | #define GSM1_ESCAPE 0x7D |
326 | #define GSM1_ESCAPE_BITS 0x20 | |
327 | #define XON 0x11 | |
328 | #define XOFF 0x13 | |
329 | ||
330 | static const struct tty_port_operations gsm_port_ops; | |
331 | ||
332 | /* | |
333 | * CRC table for GSM 0710 | |
334 | */ | |
335 | ||
336 | static const u8 gsm_fcs8[256] = { | |
337 | 0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75, | |
338 | 0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B, | |
339 | 0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69, | |
340 | 0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67, | |
341 | 0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D, | |
342 | 0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43, | |
343 | 0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51, | |
344 | 0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F, | |
345 | 0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05, | |
346 | 0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B, | |
347 | 0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19, | |
348 | 0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17, | |
349 | 0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D, | |
350 | 0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33, | |
351 | 0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21, | |
352 | 0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F, | |
353 | 0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95, | |
354 | 0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B, | |
355 | 0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89, | |
356 | 0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87, | |
357 | 0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD, | |
358 | 0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3, | |
359 | 0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1, | |
360 | 0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF, | |
361 | 0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5, | |
362 | 0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB, | |
363 | 0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9, | |
364 | 0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7, | |
365 | 0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD, | |
366 | 0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3, | |
367 | 0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1, | |
368 | 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF | |
369 | }; | |
370 | ||
371 | #define INIT_FCS 0xFF | |
372 | #define GOOD_FCS 0xCF | |
373 | ||
374 | /** | |
375 | * gsm_fcs_add - update FCS | |
376 | * @fcs: Current FCS | |
377 | * @c: Next data | |
378 | * | |
379 | * Update the FCS to include c. Uses the algorithm in the specification | |
380 | * notes. | |
381 | */ | |
382 | ||
383 | static inline u8 gsm_fcs_add(u8 fcs, u8 c) | |
384 | { | |
385 | return gsm_fcs8[fcs ^ c]; | |
386 | } | |
387 | ||
388 | /** | |
389 | * gsm_fcs_add_block - update FCS for a block | |
390 | * @fcs: Current FCS | |
391 | * @c: buffer of data | |
392 | * @len: length of buffer | |
393 | * | |
394 | * Update the FCS to include c. Uses the algorithm in the specification | |
395 | * notes. | |
396 | */ | |
397 | ||
398 | static inline u8 gsm_fcs_add_block(u8 fcs, u8 *c, int len) | |
399 | { | |
400 | while (len--) | |
401 | fcs = gsm_fcs8[fcs ^ *c++]; | |
402 | return fcs; | |
403 | } | |
404 | ||
405 | /** | |
406 | * gsm_read_ea - read a byte into an EA | |
407 | * @val: variable holding value | |
408 | * c: byte going into the EA | |
409 | * | |
410 | * Processes one byte of an EA. Updates the passed variable | |
411 | * and returns 1 if the EA is now completely read | |
412 | */ | |
413 | ||
414 | static int gsm_read_ea(unsigned int *val, u8 c) | |
415 | { | |
416 | /* Add the next 7 bits into the value */ | |
417 | *val <<= 7; | |
418 | *val |= c >> 1; | |
419 | /* Was this the last byte of the EA 1 = yes*/ | |
420 | return c & EA; | |
421 | } | |
422 | ||
423 | /** | |
424 | * gsm_encode_modem - encode modem data bits | |
425 | * @dlci: DLCI to encode from | |
426 | * | |
427 | * Returns the correct GSM encoded modem status bits (6 bit field) for | |
428 | * the current status of the DLCI and attached tty object | |
429 | */ | |
430 | ||
431 | static u8 gsm_encode_modem(const struct gsm_dlci *dlci) | |
432 | { | |
433 | u8 modembits = 0; | |
434 | /* FC is true flow control not modem bits */ | |
435 | if (dlci->throttled) | |
436 | modembits |= MDM_FC; | |
437 | if (dlci->modem_tx & TIOCM_DTR) | |
438 | modembits |= MDM_RTC; | |
439 | if (dlci->modem_tx & TIOCM_RTS) | |
440 | modembits |= MDM_RTR; | |
441 | if (dlci->modem_tx & TIOCM_RI) | |
442 | modembits |= MDM_IC; | |
443 | if (dlci->modem_tx & TIOCM_CD) | |
444 | modembits |= MDM_DV; | |
445 | return modembits; | |
446 | } | |
447 | ||
448 | /** | |
449 | * gsm_print_packet - display a frame for debug | |
450 | * @hdr: header to print before decode | |
451 | * @addr: address EA from the frame | |
452 | * @cr: C/R bit from the frame | |
453 | * @control: control including PF bit | |
454 | * @data: following data bytes | |
455 | * @dlen: length of data | |
456 | * | |
457 | * Displays a packet in human readable format for debugging purposes. The | |
458 | * style is based on amateur radio LAP-B dump display. | |
459 | */ | |
460 | ||
461 | static void gsm_print_packet(const char *hdr, int addr, int cr, | |
462 | u8 control, const u8 *data, int dlen) | |
463 | { | |
464 | if (!(debug & 1)) | |
465 | return; | |
466 | ||
5f9a31d6 | 467 | pr_info("%s %d) %c: ", hdr, addr, "RC"[cr]); |
e1eaea46 AC |
468 | |
469 | switch (control & ~PF) { | |
470 | case SABM: | |
5f9a31d6 | 471 | pr_cont("SABM"); |
e1eaea46 AC |
472 | break; |
473 | case UA: | |
5f9a31d6 | 474 | pr_cont("UA"); |
e1eaea46 AC |
475 | break; |
476 | case DISC: | |
5f9a31d6 | 477 | pr_cont("DISC"); |
e1eaea46 AC |
478 | break; |
479 | case DM: | |
5f9a31d6 | 480 | pr_cont("DM"); |
e1eaea46 AC |
481 | break; |
482 | case UI: | |
5f9a31d6 | 483 | pr_cont("UI"); |
e1eaea46 AC |
484 | break; |
485 | case UIH: | |
5f9a31d6 | 486 | pr_cont("UIH"); |
e1eaea46 AC |
487 | break; |
488 | default: | |
489 | if (!(control & 0x01)) { | |
5f9a31d6 AC |
490 | pr_cont("I N(S)%d N(R)%d", |
491 | (control & 0x0E) >> 1, (control & 0xE) >> 5); | |
e1eaea46 | 492 | } else switch (control & 0x0F) { |
5f9a31d6 AC |
493 | case RR: |
494 | pr_cont("RR(%d)", (control & 0xE0) >> 5); | |
495 | break; | |
496 | case RNR: | |
497 | pr_cont("RNR(%d)", (control & 0xE0) >> 5); | |
498 | break; | |
499 | case REJ: | |
500 | pr_cont("REJ(%d)", (control & 0xE0) >> 5); | |
501 | break; | |
502 | default: | |
503 | pr_cont("[%02X]", control); | |
e1eaea46 AC |
504 | } |
505 | } | |
506 | ||
507 | if (control & PF) | |
5f9a31d6 | 508 | pr_cont("(P)"); |
e1eaea46 | 509 | else |
5f9a31d6 | 510 | pr_cont("(F)"); |
e1eaea46 AC |
511 | |
512 | if (dlen) { | |
513 | int ct = 0; | |
514 | while (dlen--) { | |
5f9a31d6 AC |
515 | if (ct % 8 == 0) { |
516 | pr_cont("\n"); | |
517 | pr_debug(" "); | |
518 | } | |
519 | pr_cont("%02X ", *data++); | |
e1eaea46 AC |
520 | ct++; |
521 | } | |
522 | } | |
5f9a31d6 | 523 | pr_cont("\n"); |
e1eaea46 AC |
524 | } |
525 | ||
526 | ||
527 | /* | |
528 | * Link level transmission side | |
529 | */ | |
530 | ||
531 | /** | |
532 | * gsm_stuff_packet - bytestuff a packet | |
533 | * @ibuf: input | |
534 | * @obuf: output | |
535 | * @len: length of input | |
536 | * | |
537 | * Expand a buffer by bytestuffing it. The worst case size change | |
538 | * is doubling and the caller is responsible for handing out | |
539 | * suitable sized buffers. | |
540 | */ | |
541 | ||
542 | static int gsm_stuff_frame(const u8 *input, u8 *output, int len) | |
543 | { | |
544 | int olen = 0; | |
545 | while (len--) { | |
546 | if (*input == GSM1_SOF || *input == GSM1_ESCAPE | |
547 | || *input == XON || *input == XOFF) { | |
548 | *output++ = GSM1_ESCAPE; | |
549 | *output++ = *input++ ^ GSM1_ESCAPE_BITS; | |
550 | olen++; | |
551 | } else | |
552 | *output++ = *input++; | |
553 | olen++; | |
554 | } | |
555 | return olen; | |
556 | } | |
557 | ||
e1eaea46 AC |
558 | /** |
559 | * gsm_send - send a control frame | |
560 | * @gsm: our GSM mux | |
561 | * @addr: address for control frame | |
562 | * @cr: command/response bit | |
563 | * @control: control byte including PF bit | |
564 | * | |
565 | * Format up and transmit a control frame. These do not go via the | |
566 | * queueing logic as they should be transmitted ahead of data when | |
567 | * they are needed. | |
568 | * | |
569 | * FIXME: Lock versus data TX path | |
570 | */ | |
571 | ||
572 | static void gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) | |
573 | { | |
574 | int len; | |
575 | u8 cbuf[10]; | |
576 | u8 ibuf[3]; | |
577 | ||
578 | switch (gsm->encoding) { | |
579 | case 0: | |
580 | cbuf[0] = GSM0_SOF; | |
581 | cbuf[1] = (addr << 2) | (cr << 1) | EA; | |
582 | cbuf[2] = control; | |
583 | cbuf[3] = EA; /* Length of data = 0 */ | |
584 | cbuf[4] = 0xFF - gsm_fcs_add_block(INIT_FCS, cbuf + 1, 3); | |
585 | cbuf[5] = GSM0_SOF; | |
586 | len = 6; | |
587 | break; | |
588 | case 1: | |
589 | case 2: | |
590 | /* Control frame + packing (but not frame stuffing) in mode 1 */ | |
591 | ibuf[0] = (addr << 2) | (cr << 1) | EA; | |
592 | ibuf[1] = control; | |
593 | ibuf[2] = 0xFF - gsm_fcs_add_block(INIT_FCS, ibuf, 2); | |
594 | /* Stuffing may double the size worst case */ | |
595 | len = gsm_stuff_frame(ibuf, cbuf + 1, 3); | |
596 | /* Now add the SOF markers */ | |
597 | cbuf[0] = GSM1_SOF; | |
598 | cbuf[len + 1] = GSM1_SOF; | |
599 | /* FIXME: we can omit the lead one in many cases */ | |
600 | len += 2; | |
601 | break; | |
602 | default: | |
603 | WARN_ON(1); | |
604 | return; | |
605 | } | |
606 | gsm->output(gsm, cbuf, len); | |
607 | gsm_print_packet("-->", addr, cr, control, NULL, 0); | |
608 | } | |
609 | ||
610 | /** | |
611 | * gsm_response - send a control response | |
612 | * @gsm: our GSM mux | |
613 | * @addr: address for control frame | |
614 | * @control: control byte including PF bit | |
615 | * | |
616 | * Format up and transmit a link level response frame. | |
617 | */ | |
618 | ||
619 | static inline void gsm_response(struct gsm_mux *gsm, int addr, int control) | |
620 | { | |
621 | gsm_send(gsm, addr, 0, control); | |
622 | } | |
623 | ||
624 | /** | |
625 | * gsm_command - send a control command | |
626 | * @gsm: our GSM mux | |
627 | * @addr: address for control frame | |
628 | * @control: control byte including PF bit | |
629 | * | |
630 | * Format up and transmit a link level command frame. | |
631 | */ | |
632 | ||
633 | static inline void gsm_command(struct gsm_mux *gsm, int addr, int control) | |
634 | { | |
635 | gsm_send(gsm, addr, 1, control); | |
636 | } | |
637 | ||
638 | /* Data transmission */ | |
639 | ||
640 | #define HDR_LEN 6 /* ADDR CTRL [LEN.2] DATA FCS */ | |
641 | ||
642 | /** | |
643 | * gsm_data_alloc - allocate data frame | |
644 | * @gsm: GSM mux | |
645 | * @addr: DLCI address | |
646 | * @len: length excluding header and FCS | |
647 | * @ctrl: control byte | |
648 | * | |
649 | * Allocate a new data buffer for sending frames with data. Space is left | |
650 | * at the front for header bytes but that is treated as an implementation | |
651 | * detail and not for the high level code to use | |
652 | */ | |
653 | ||
654 | static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len, | |
655 | u8 ctrl) | |
656 | { | |
657 | struct gsm_msg *m = kmalloc(sizeof(struct gsm_msg) + len + HDR_LEN, | |
658 | GFP_ATOMIC); | |
659 | if (m == NULL) | |
660 | return NULL; | |
661 | m->data = m->buffer + HDR_LEN - 1; /* Allow for FCS */ | |
662 | m->len = len; | |
663 | m->addr = addr; | |
664 | m->ctrl = ctrl; | |
665 | m->next = NULL; | |
666 | return m; | |
667 | } | |
668 | ||
669 | /** | |
670 | * gsm_data_kick - poke the queue | |
671 | * @gsm: GSM Mux | |
672 | * | |
673 | * The tty device has called us to indicate that room has appeared in | |
674 | * the transmit queue. Ram more data into the pipe if we have any | |
675 | * | |
676 | * FIXME: lock against link layer control transmissions | |
677 | */ | |
678 | ||
679 | static void gsm_data_kick(struct gsm_mux *gsm) | |
680 | { | |
681 | struct gsm_msg *msg = gsm->tx_head; | |
682 | int len; | |
683 | int skip_sof = 0; | |
684 | ||
685 | /* FIXME: We need to apply this solely to data messages */ | |
686 | if (gsm->constipated) | |
687 | return; | |
688 | ||
689 | while (gsm->tx_head != NULL) { | |
690 | msg = gsm->tx_head; | |
691 | if (gsm->encoding != 0) { | |
692 | gsm->txframe[0] = GSM1_SOF; | |
693 | len = gsm_stuff_frame(msg->data, | |
694 | gsm->txframe + 1, msg->len); | |
695 | gsm->txframe[len + 1] = GSM1_SOF; | |
696 | len += 2; | |
697 | } else { | |
698 | gsm->txframe[0] = GSM0_SOF; | |
699 | memcpy(gsm->txframe + 1 , msg->data, msg->len); | |
700 | gsm->txframe[msg->len + 1] = GSM0_SOF; | |
701 | len = msg->len + 2; | |
702 | } | |
703 | ||
0a77c4f9 JP |
704 | if (debug & 4) |
705 | print_hex_dump_bytes("gsm_data_kick: ", | |
706 | DUMP_PREFIX_OFFSET, | |
707 | gsm->txframe, len); | |
e1eaea46 AC |
708 | |
709 | if (gsm->output(gsm, gsm->txframe + skip_sof, | |
710 | len - skip_sof) < 0) | |
711 | break; | |
712 | /* FIXME: Can eliminate one SOF in many more cases */ | |
713 | gsm->tx_head = msg->next; | |
714 | if (gsm->tx_head == NULL) | |
715 | gsm->tx_tail = NULL; | |
716 | gsm->tx_bytes -= msg->len; | |
717 | kfree(msg); | |
718 | /* For a burst of frames skip the extra SOF within the | |
719 | burst */ | |
720 | skip_sof = 1; | |
721 | } | |
722 | } | |
723 | ||
724 | /** | |
725 | * __gsm_data_queue - queue a UI or UIH frame | |
726 | * @dlci: DLCI sending the data | |
727 | * @msg: message queued | |
728 | * | |
729 | * Add data to the transmit queue and try and get stuff moving | |
730 | * out of the mux tty if not already doing so. The Caller must hold | |
731 | * the gsm tx lock. | |
732 | */ | |
733 | ||
734 | static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) | |
735 | { | |
736 | struct gsm_mux *gsm = dlci->gsm; | |
737 | u8 *dp = msg->data; | |
738 | u8 *fcs = dp + msg->len; | |
739 | ||
740 | /* Fill in the header */ | |
741 | if (gsm->encoding == 0) { | |
742 | if (msg->len < 128) | |
743 | *--dp = (msg->len << 1) | EA; | |
744 | else { | |
be7a7411 KM |
745 | *--dp = (msg->len >> 7); /* bits 7 - 15 */ |
746 | *--dp = (msg->len & 127) << 1; /* bits 0 - 6 */ | |
e1eaea46 AC |
747 | } |
748 | } | |
749 | ||
750 | *--dp = msg->ctrl; | |
751 | if (gsm->initiator) | |
752 | *--dp = (msg->addr << 2) | 2 | EA; | |
753 | else | |
754 | *--dp = (msg->addr << 2) | EA; | |
755 | *fcs = gsm_fcs_add_block(INIT_FCS, dp , msg->data - dp); | |
756 | /* Ugly protocol layering violation */ | |
757 | if (msg->ctrl == UI || msg->ctrl == (UI|PF)) | |
758 | *fcs = gsm_fcs_add_block(*fcs, msg->data, msg->len); | |
759 | *fcs = 0xFF - *fcs; | |
760 | ||
761 | gsm_print_packet("Q> ", msg->addr, gsm->initiator, msg->ctrl, | |
762 | msg->data, msg->len); | |
763 | ||
764 | /* Move the header back and adjust the length, also allow for the FCS | |
765 | now tacked on the end */ | |
766 | msg->len += (msg->data - dp) + 1; | |
767 | msg->data = dp; | |
768 | ||
769 | /* Add to the actual output queue */ | |
770 | if (gsm->tx_tail) | |
771 | gsm->tx_tail->next = msg; | |
772 | else | |
773 | gsm->tx_head = msg; | |
774 | gsm->tx_tail = msg; | |
775 | gsm->tx_bytes += msg->len; | |
776 | gsm_data_kick(gsm); | |
777 | } | |
778 | ||
779 | /** | |
780 | * gsm_data_queue - queue a UI or UIH frame | |
781 | * @dlci: DLCI sending the data | |
782 | * @msg: message queued | |
783 | * | |
784 | * Add data to the transmit queue and try and get stuff moving | |
785 | * out of the mux tty if not already doing so. Take the | |
786 | * the gsm tx lock and dlci lock. | |
787 | */ | |
788 | ||
789 | static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) | |
790 | { | |
791 | unsigned long flags; | |
792 | spin_lock_irqsave(&dlci->gsm->tx_lock, flags); | |
793 | __gsm_data_queue(dlci, msg); | |
794 | spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); | |
795 | } | |
796 | ||
797 | /** | |
798 | * gsm_dlci_data_output - try and push data out of a DLCI | |
799 | * @gsm: mux | |
800 | * @dlci: the DLCI to pull data from | |
801 | * | |
802 | * Pull data from a DLCI and send it into the transmit queue if there | |
803 | * is data. Keep to the MRU of the mux. This path handles the usual tty | |
804 | * interface which is a byte stream with optional modem data. | |
805 | * | |
806 | * Caller must hold the tx_lock of the mux. | |
807 | */ | |
808 | ||
809 | static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) | |
810 | { | |
811 | struct gsm_msg *msg; | |
812 | u8 *dp; | |
813 | int len, size; | |
814 | int h = dlci->adaption - 1; | |
815 | ||
816 | len = kfifo_len(dlci->fifo); | |
817 | if (len == 0) | |
818 | return 0; | |
819 | ||
820 | /* MTU/MRU count only the data bits */ | |
821 | if (len > gsm->mtu) | |
822 | len = gsm->mtu; | |
823 | ||
824 | size = len + h; | |
825 | ||
826 | msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); | |
827 | /* FIXME: need a timer or something to kick this so it can't | |
828 | get stuck with no work outstanding and no buffer free */ | |
829 | if (msg == NULL) | |
830 | return -ENOMEM; | |
831 | dp = msg->data; | |
832 | switch (dlci->adaption) { | |
833 | case 1: /* Unstructured */ | |
834 | break; | |
835 | case 2: /* Unstructed with modem bits. Always one byte as we never | |
836 | send inline break data */ | |
837 | *dp += gsm_encode_modem(dlci); | |
838 | len--; | |
839 | break; | |
840 | } | |
841 | WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len); | |
842 | __gsm_data_queue(dlci, msg); | |
843 | /* Bytes of data we used up */ | |
844 | return size; | |
845 | } | |
846 | ||
847 | /** | |
848 | * gsm_dlci_data_output_framed - try and push data out of a DLCI | |
849 | * @gsm: mux | |
850 | * @dlci: the DLCI to pull data from | |
851 | * | |
852 | * Pull data from a DLCI and send it into the transmit queue if there | |
853 | * is data. Keep to the MRU of the mux. This path handles framed data | |
854 | * queued as skbuffs to the DLCI. | |
855 | * | |
856 | * Caller must hold the tx_lock of the mux. | |
857 | */ | |
858 | ||
859 | static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, | |
860 | struct gsm_dlci *dlci) | |
861 | { | |
862 | struct gsm_msg *msg; | |
863 | u8 *dp; | |
864 | int len, size; | |
865 | int last = 0, first = 0; | |
866 | int overhead = 0; | |
867 | ||
868 | /* One byte per frame is used for B/F flags */ | |
869 | if (dlci->adaption == 4) | |
870 | overhead = 1; | |
871 | ||
872 | /* dlci->skb is locked by tx_lock */ | |
873 | if (dlci->skb == NULL) { | |
874 | dlci->skb = skb_dequeue(&dlci->skb_list); | |
875 | if (dlci->skb == NULL) | |
876 | return 0; | |
877 | first = 1; | |
878 | } | |
879 | len = dlci->skb->len + overhead; | |
880 | ||
881 | /* MTU/MRU count only the data bits */ | |
882 | if (len > gsm->mtu) { | |
883 | if (dlci->adaption == 3) { | |
884 | /* Over long frame, bin it */ | |
885 | kfree_skb(dlci->skb); | |
886 | dlci->skb = NULL; | |
887 | return 0; | |
888 | } | |
889 | len = gsm->mtu; | |
890 | } else | |
891 | last = 1; | |
892 | ||
893 | size = len + overhead; | |
894 | msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); | |
895 | ||
896 | /* FIXME: need a timer or something to kick this so it can't | |
897 | get stuck with no work outstanding and no buffer free */ | |
898 | if (msg == NULL) | |
899 | return -ENOMEM; | |
900 | dp = msg->data; | |
901 | ||
902 | if (dlci->adaption == 4) { /* Interruptible framed (Packetised Data) */ | |
903 | /* Flag byte to carry the start/end info */ | |
904 | *dp++ = last << 7 | first << 6 | 1; /* EA */ | |
905 | len--; | |
906 | } | |
57f2104f RG |
907 | memcpy(dp, dlci->skb->data, len); |
908 | skb_pull(dlci->skb, len); | |
e1eaea46 | 909 | __gsm_data_queue(dlci, msg); |
bcd5abe2 RG |
910 | if (last) { |
911 | kfree_skb(dlci->skb); | |
e1eaea46 | 912 | dlci->skb = NULL; |
bcd5abe2 | 913 | } |
e1eaea46 AC |
914 | return size; |
915 | } | |
916 | ||
917 | /** | |
918 | * gsm_dlci_data_sweep - look for data to send | |
919 | * @gsm: the GSM mux | |
920 | * | |
921 | * Sweep the GSM mux channels in priority order looking for ones with | |
922 | * data to send. We could do with optimising this scan a bit. We aim | |
923 | * to fill the queue totally or up to TX_THRESH_HI bytes. Once we hit | |
924 | * TX_THRESH_LO we get called again | |
925 | * | |
926 | * FIXME: We should round robin between groups and in theory you can | |
927 | * renegotiate DLCI priorities with optional stuff. Needs optimising. | |
928 | */ | |
929 | ||
930 | static void gsm_dlci_data_sweep(struct gsm_mux *gsm) | |
931 | { | |
932 | int len; | |
933 | /* Priority ordering: We should do priority with RR of the groups */ | |
934 | int i = 1; | |
e1eaea46 | 935 | |
e1eaea46 AC |
936 | while (i < NUM_DLCI) { |
937 | struct gsm_dlci *dlci; | |
938 | ||
939 | if (gsm->tx_bytes > TX_THRESH_HI) | |
940 | break; | |
941 | dlci = gsm->dlci[i]; | |
942 | if (dlci == NULL || dlci->constipated) { | |
943 | i++; | |
944 | continue; | |
945 | } | |
bcd5abe2 | 946 | if (dlci->adaption < 3 && !dlci->net) |
e1eaea46 AC |
947 | len = gsm_dlci_data_output(gsm, dlci); |
948 | else | |
949 | len = gsm_dlci_data_output_framed(gsm, dlci); | |
950 | if (len < 0) | |
e73790a5 | 951 | break; |
e1eaea46 AC |
952 | /* DLCI empty - try the next */ |
953 | if (len == 0) | |
954 | i++; | |
955 | } | |
e1eaea46 AC |
956 | } |
957 | ||
958 | /** | |
959 | * gsm_dlci_data_kick - transmit if possible | |
960 | * @dlci: DLCI to kick | |
961 | * | |
962 | * Transmit data from this DLCI if the queue is empty. We can't rely on | |
963 | * a tty wakeup except when we filled the pipe so we need to fire off | |
964 | * new data ourselves in other cases. | |
965 | */ | |
966 | ||
967 | static void gsm_dlci_data_kick(struct gsm_dlci *dlci) | |
968 | { | |
969 | unsigned long flags; | |
970 | ||
971 | spin_lock_irqsave(&dlci->gsm->tx_lock, flags); | |
972 | /* If we have nothing running then we need to fire up */ | |
bcd5abe2 RG |
973 | if (dlci->gsm->tx_bytes == 0) { |
974 | if (dlci->net) | |
975 | gsm_dlci_data_output_framed(dlci->gsm, dlci); | |
976 | else | |
977 | gsm_dlci_data_output(dlci->gsm, dlci); | |
978 | } else if (dlci->gsm->tx_bytes < TX_THRESH_LO) | |
e1eaea46 AC |
979 | gsm_dlci_data_sweep(dlci->gsm); |
980 | spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); | |
981 | } | |
982 | ||
983 | /* | |
984 | * Control message processing | |
985 | */ | |
986 | ||
987 | ||
988 | /** | |
989 | * gsm_control_reply - send a response frame to a control | |
990 | * @gsm: gsm channel | |
991 | * @cmd: the command to use | |
992 | * @data: data to follow encoded info | |
993 | * @dlen: length of data | |
994 | * | |
995 | * Encode up and queue a UI/UIH frame containing our response. | |
996 | */ | |
997 | ||
998 | static void gsm_control_reply(struct gsm_mux *gsm, int cmd, u8 *data, | |
999 | int dlen) | |
1000 | { | |
1001 | struct gsm_msg *msg; | |
1002 | msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype); | |
093d8046 KM |
1003 | if (msg == NULL) |
1004 | return; | |
e1eaea46 AC |
1005 | msg->data[0] = (cmd & 0xFE) << 1 | EA; /* Clear C/R */ |
1006 | msg->data[1] = (dlen << 1) | EA; | |
1007 | memcpy(msg->data + 2, data, dlen); | |
1008 | gsm_data_queue(gsm->dlci[0], msg); | |
1009 | } | |
1010 | ||
1011 | /** | |
1012 | * gsm_process_modem - process received modem status | |
1013 | * @tty: virtual tty bound to the DLCI | |
1014 | * @dlci: DLCI to affect | |
1015 | * @modem: modem bits (full EA) | |
1016 | * | |
1017 | * Used when a modem control message or line state inline in adaption | |
1018 | * layer 2 is processed. Sort out the local modem state and throttles | |
1019 | */ | |
1020 | ||
1021 | static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci, | |
7263287a | 1022 | u32 modem, int clen) |
e1eaea46 AC |
1023 | { |
1024 | int mlines = 0; | |
7263287a RG |
1025 | u8 brk = 0; |
1026 | ||
1027 | /* The modem status command can either contain one octet (v.24 signals) | |
1028 | or two octets (v.24 signals + break signals). The length field will | |
1029 | either be 2 or 3 respectively. This is specified in section | |
1030 | 5.4.6.3.7 of the 27.010 mux spec. */ | |
1031 | ||
1032 | if (clen == 2) | |
1033 | modem = modem & 0x7f; | |
1034 | else { | |
1035 | brk = modem & 0x7f; | |
1036 | modem = (modem >> 7) & 0x7f; | |
1037 | }; | |
e1eaea46 AC |
1038 | |
1039 | /* Flow control/ready to communicate */ | |
1040 | if (modem & MDM_FC) { | |
1041 | /* Need to throttle our output on this device */ | |
1042 | dlci->constipated = 1; | |
1043 | } | |
1044 | if (modem & MDM_RTC) { | |
1045 | mlines |= TIOCM_DSR | TIOCM_DTR; | |
1046 | dlci->constipated = 0; | |
1047 | gsm_dlci_data_kick(dlci); | |
1048 | } | |
1049 | /* Map modem bits */ | |
1050 | if (modem & MDM_RTR) | |
1051 | mlines |= TIOCM_RTS | TIOCM_CTS; | |
1052 | if (modem & MDM_IC) | |
1053 | mlines |= TIOCM_RI; | |
1054 | if (modem & MDM_DV) | |
1055 | mlines |= TIOCM_CD; | |
1056 | ||
1057 | /* Carrier drop -> hangup */ | |
1058 | if (tty) { | |
1059 | if ((mlines & TIOCM_CD) == 0 && (dlci->modem_rx & TIOCM_CD)) | |
1060 | if (!(tty->termios->c_cflag & CLOCAL)) | |
1061 | tty_hangup(tty); | |
1062 | if (brk & 0x01) | |
1063 | tty_insert_flip_char(tty, 0, TTY_BREAK); | |
1064 | } | |
1065 | dlci->modem_rx = mlines; | |
1066 | } | |
1067 | ||
1068 | /** | |
1069 | * gsm_control_modem - modem status received | |
1070 | * @gsm: GSM channel | |
1071 | * @data: data following command | |
1072 | * @clen: command length | |
1073 | * | |
1074 | * We have received a modem status control message. This is used by | |
1075 | * the GSM mux protocol to pass virtual modem line status and optionally | |
1076 | * to indicate break signals. Unpack it, convert to Linux representation | |
1077 | * and if need be stuff a break message down the tty. | |
1078 | */ | |
1079 | ||
1080 | static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen) | |
1081 | { | |
1082 | unsigned int addr = 0; | |
1083 | unsigned int modem = 0; | |
1084 | struct gsm_dlci *dlci; | |
1085 | int len = clen; | |
1086 | u8 *dp = data; | |
1087 | struct tty_struct *tty; | |
1088 | ||
1089 | while (gsm_read_ea(&addr, *dp++) == 0) { | |
1090 | len--; | |
1091 | if (len == 0) | |
1092 | return; | |
1093 | } | |
1094 | /* Must be at least one byte following the EA */ | |
1095 | len--; | |
1096 | if (len <= 0) | |
1097 | return; | |
1098 | ||
1099 | addr >>= 1; | |
1100 | /* Closed port, or invalid ? */ | |
1101 | if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) | |
1102 | return; | |
1103 | dlci = gsm->dlci[addr]; | |
1104 | ||
1105 | while (gsm_read_ea(&modem, *dp++) == 0) { | |
1106 | len--; | |
1107 | if (len == 0) | |
1108 | return; | |
1109 | } | |
1110 | tty = tty_port_tty_get(&dlci->port); | |
7263287a | 1111 | gsm_process_modem(tty, dlci, modem, clen); |
e1eaea46 AC |
1112 | if (tty) { |
1113 | tty_wakeup(tty); | |
1114 | tty_kref_put(tty); | |
1115 | } | |
1116 | gsm_control_reply(gsm, CMD_MSC, data, clen); | |
1117 | } | |
1118 | ||
1119 | /** | |
1120 | * gsm_control_rls - remote line status | |
1121 | * @gsm: GSM channel | |
1122 | * @data: data bytes | |
1123 | * @clen: data length | |
1124 | * | |
1125 | * The modem sends us a two byte message on the control channel whenever | |
1126 | * it wishes to send us an error state from the virtual link. Stuff | |
1127 | * this into the uplink tty if present | |
1128 | */ | |
1129 | ||
1130 | static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen) | |
1131 | { | |
1132 | struct tty_struct *tty; | |
1133 | unsigned int addr = 0 ; | |
1134 | u8 bits; | |
1135 | int len = clen; | |
1136 | u8 *dp = data; | |
1137 | ||
1138 | while (gsm_read_ea(&addr, *dp++) == 0) { | |
1139 | len--; | |
1140 | if (len == 0) | |
1141 | return; | |
1142 | } | |
1143 | /* Must be at least one byte following ea */ | |
1144 | len--; | |
1145 | if (len <= 0) | |
1146 | return; | |
1147 | addr >>= 1; | |
1148 | /* Closed port, or invalid ? */ | |
1149 | if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) | |
1150 | return; | |
1151 | /* No error ? */ | |
1152 | bits = *dp; | |
1153 | if ((bits & 1) == 0) | |
1154 | return; | |
1155 | /* See if we have an uplink tty */ | |
1156 | tty = tty_port_tty_get(&gsm->dlci[addr]->port); | |
1157 | ||
1158 | if (tty) { | |
1159 | if (bits & 2) | |
1160 | tty_insert_flip_char(tty, 0, TTY_OVERRUN); | |
1161 | if (bits & 4) | |
1162 | tty_insert_flip_char(tty, 0, TTY_PARITY); | |
1163 | if (bits & 8) | |
1164 | tty_insert_flip_char(tty, 0, TTY_FRAME); | |
1165 | tty_flip_buffer_push(tty); | |
1166 | tty_kref_put(tty); | |
1167 | } | |
1168 | gsm_control_reply(gsm, CMD_RLS, data, clen); | |
1169 | } | |
1170 | ||
1171 | static void gsm_dlci_begin_close(struct gsm_dlci *dlci); | |
1172 | ||
1173 | /** | |
1174 | * gsm_control_message - DLCI 0 control processing | |
1175 | * @gsm: our GSM mux | |
1176 | * @command: the command EA | |
1177 | * @data: data beyond the command/length EAs | |
1178 | * @clen: length | |
1179 | * | |
1180 | * Input processor for control messages from the other end of the link. | |
1181 | * Processes the incoming request and queues a response frame or an | |
1182 | * NSC response if not supported | |
1183 | */ | |
1184 | ||
1185 | static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, | |
1186 | u8 *data, int clen) | |
1187 | { | |
1188 | u8 buf[1]; | |
1189 | switch (command) { | |
1190 | case CMD_CLD: { | |
1191 | struct gsm_dlci *dlci = gsm->dlci[0]; | |
1192 | /* Modem wishes to close down */ | |
1193 | if (dlci) { | |
1194 | dlci->dead = 1; | |
1195 | gsm->dead = 1; | |
1196 | gsm_dlci_begin_close(dlci); | |
1197 | } | |
1198 | } | |
1199 | break; | |
1200 | case CMD_TEST: | |
1201 | /* Modem wishes to test, reply with the data */ | |
1202 | gsm_control_reply(gsm, CMD_TEST, data, clen); | |
1203 | break; | |
1204 | case CMD_FCON: | |
1205 | /* Modem wants us to STFU */ | |
1206 | gsm->constipated = 1; | |
1207 | gsm_control_reply(gsm, CMD_FCON, NULL, 0); | |
1208 | break; | |
1209 | case CMD_FCOFF: | |
1210 | /* Modem can accept data again */ | |
1211 | gsm->constipated = 0; | |
1212 | gsm_control_reply(gsm, CMD_FCOFF, NULL, 0); | |
1213 | /* Kick the link in case it is idling */ | |
1214 | gsm_data_kick(gsm); | |
1215 | break; | |
1216 | case CMD_MSC: | |
1217 | /* Out of band modem line change indicator for a DLCI */ | |
1218 | gsm_control_modem(gsm, data, clen); | |
1219 | break; | |
1220 | case CMD_RLS: | |
1221 | /* Out of band error reception for a DLCI */ | |
1222 | gsm_control_rls(gsm, data, clen); | |
1223 | break; | |
1224 | case CMD_PSC: | |
1225 | /* Modem wishes to enter power saving state */ | |
1226 | gsm_control_reply(gsm, CMD_PSC, NULL, 0); | |
1227 | break; | |
1228 | /* Optional unsupported commands */ | |
1229 | case CMD_PN: /* Parameter negotiation */ | |
25985edc LDM |
1230 | case CMD_RPN: /* Remote port negotiation */ |
1231 | case CMD_SNC: /* Service negotiation command */ | |
e1eaea46 AC |
1232 | default: |
1233 | /* Reply to bad commands with an NSC */ | |
1234 | buf[0] = command; | |
1235 | gsm_control_reply(gsm, CMD_NSC, buf, 1); | |
1236 | break; | |
1237 | } | |
1238 | } | |
1239 | ||
1240 | /** | |
1241 | * gsm_control_response - process a response to our control | |
1242 | * @gsm: our GSM mux | |
1243 | * @command: the command (response) EA | |
1244 | * @data: data beyond the command/length EA | |
1245 | * @clen: length | |
1246 | * | |
1247 | * Process a response to an outstanding command. We only allow a single | |
1248 | * control message in flight so this is fairly easy. All the clean up | |
1249 | * is done by the caller, we just update the fields, flag it as done | |
1250 | * and return | |
1251 | */ | |
1252 | ||
1253 | static void gsm_control_response(struct gsm_mux *gsm, unsigned int command, | |
1254 | u8 *data, int clen) | |
1255 | { | |
1256 | struct gsm_control *ctrl; | |
1257 | unsigned long flags; | |
1258 | ||
1259 | spin_lock_irqsave(&gsm->control_lock, flags); | |
1260 | ||
1261 | ctrl = gsm->pending_cmd; | |
1262 | /* Does the reply match our command */ | |
1263 | command |= 1; | |
1264 | if (ctrl != NULL && (command == ctrl->cmd || command == CMD_NSC)) { | |
1265 | /* Our command was replied to, kill the retry timer */ | |
1266 | del_timer(&gsm->t2_timer); | |
1267 | gsm->pending_cmd = NULL; | |
1268 | /* Rejected by the other end */ | |
1269 | if (command == CMD_NSC) | |
1270 | ctrl->error = -EOPNOTSUPP; | |
1271 | ctrl->done = 1; | |
1272 | wake_up(&gsm->event); | |
1273 | } | |
1274 | spin_unlock_irqrestore(&gsm->control_lock, flags); | |
1275 | } | |
1276 | ||
1277 | /** | |
5f9a31d6 | 1278 | * gsm_control_transmit - send control packet |
e1eaea46 AC |
1279 | * @gsm: gsm mux |
1280 | * @ctrl: frame to send | |
1281 | * | |
1282 | * Send out a pending control command (called under control lock) | |
1283 | */ | |
1284 | ||
1285 | static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl) | |
1286 | { | |
ed43b47b | 1287 | struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1, gsm->ftype); |
e1eaea46 AC |
1288 | if (msg == NULL) |
1289 | return; | |
1290 | msg->data[0] = (ctrl->cmd << 1) | 2 | EA; /* command */ | |
1291 | memcpy(msg->data + 1, ctrl->data, ctrl->len); | |
1292 | gsm_data_queue(gsm->dlci[0], msg); | |
1293 | } | |
1294 | ||
1295 | /** | |
1296 | * gsm_control_retransmit - retransmit a control frame | |
1297 | * @data: pointer to our gsm object | |
1298 | * | |
1299 | * Called off the T2 timer expiry in order to retransmit control frames | |
1300 | * that have been lost in the system somewhere. The control_lock protects | |
1301 | * us from colliding with another sender or a receive completion event. | |
1302 | * In that situation the timer may still occur in a small window but | |
1303 | * gsm->pending_cmd will be NULL and we just let the timer expire. | |
1304 | */ | |
1305 | ||
1306 | static void gsm_control_retransmit(unsigned long data) | |
1307 | { | |
1308 | struct gsm_mux *gsm = (struct gsm_mux *)data; | |
1309 | struct gsm_control *ctrl; | |
1310 | unsigned long flags; | |
1311 | spin_lock_irqsave(&gsm->control_lock, flags); | |
1312 | ctrl = gsm->pending_cmd; | |
1313 | if (ctrl) { | |
1314 | gsm->cretries--; | |
1315 | if (gsm->cretries == 0) { | |
1316 | gsm->pending_cmd = NULL; | |
1317 | ctrl->error = -ETIMEDOUT; | |
1318 | ctrl->done = 1; | |
1319 | spin_unlock_irqrestore(&gsm->control_lock, flags); | |
1320 | wake_up(&gsm->event); | |
1321 | return; | |
1322 | } | |
1323 | gsm_control_transmit(gsm, ctrl); | |
1324 | mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); | |
1325 | } | |
1326 | spin_unlock_irqrestore(&gsm->control_lock, flags); | |
1327 | } | |
1328 | ||
1329 | /** | |
1330 | * gsm_control_send - send a control frame on DLCI 0 | |
1331 | * @gsm: the GSM channel | |
1332 | * @command: command to send including CR bit | |
1333 | * @data: bytes of data (must be kmalloced) | |
1334 | * @len: length of the block to send | |
1335 | * | |
1336 | * Queue and dispatch a control command. Only one command can be | |
1337 | * active at a time. In theory more can be outstanding but the matching | |
1338 | * gets really complicated so for now stick to one outstanding. | |
1339 | */ | |
1340 | ||
1341 | static struct gsm_control *gsm_control_send(struct gsm_mux *gsm, | |
1342 | unsigned int command, u8 *data, int clen) | |
1343 | { | |
1344 | struct gsm_control *ctrl = kzalloc(sizeof(struct gsm_control), | |
1345 | GFP_KERNEL); | |
1346 | unsigned long flags; | |
1347 | if (ctrl == NULL) | |
1348 | return NULL; | |
1349 | retry: | |
1350 | wait_event(gsm->event, gsm->pending_cmd == NULL); | |
1351 | spin_lock_irqsave(&gsm->control_lock, flags); | |
1352 | if (gsm->pending_cmd != NULL) { | |
1353 | spin_unlock_irqrestore(&gsm->control_lock, flags); | |
1354 | goto retry; | |
1355 | } | |
1356 | ctrl->cmd = command; | |
1357 | ctrl->data = data; | |
1358 | ctrl->len = clen; | |
1359 | gsm->pending_cmd = ctrl; | |
1360 | gsm->cretries = gsm->n2; | |
1361 | mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); | |
1362 | gsm_control_transmit(gsm, ctrl); | |
1363 | spin_unlock_irqrestore(&gsm->control_lock, flags); | |
1364 | return ctrl; | |
1365 | } | |
1366 | ||
1367 | /** | |
1368 | * gsm_control_wait - wait for a control to finish | |
1369 | * @gsm: GSM mux | |
1370 | * @control: control we are waiting on | |
1371 | * | |
1372 | * Waits for the control to complete or time out. Frees any used | |
1373 | * resources and returns 0 for success, or an error if the remote | |
1374 | * rejected or ignored the request. | |
1375 | */ | |
1376 | ||
1377 | static int gsm_control_wait(struct gsm_mux *gsm, struct gsm_control *control) | |
1378 | { | |
1379 | int err; | |
1380 | wait_event(gsm->event, control->done == 1); | |
1381 | err = control->error; | |
1382 | kfree(control); | |
1383 | return err; | |
1384 | } | |
1385 | ||
1386 | ||
1387 | /* | |
1388 | * DLCI level handling: Needs krefs | |
1389 | */ | |
1390 | ||
1391 | /* | |
1392 | * State transitions and timers | |
1393 | */ | |
1394 | ||
1395 | /** | |
1396 | * gsm_dlci_close - a DLCI has closed | |
1397 | * @dlci: DLCI that closed | |
1398 | * | |
1399 | * Perform processing when moving a DLCI into closed state. If there | |
1400 | * is an attached tty this is hung up | |
1401 | */ | |
1402 | ||
1403 | static void gsm_dlci_close(struct gsm_dlci *dlci) | |
1404 | { | |
1405 | del_timer(&dlci->t1); | |
1406 | if (debug & 8) | |
5f9a31d6 | 1407 | pr_debug("DLCI %d goes closed.\n", dlci->addr); |
e1eaea46 AC |
1408 | dlci->state = DLCI_CLOSED; |
1409 | if (dlci->addr != 0) { | |
1410 | struct tty_struct *tty = tty_port_tty_get(&dlci->port); | |
1411 | if (tty) { | |
1412 | tty_hangup(tty); | |
1413 | tty_kref_put(tty); | |
1414 | } | |
1415 | kfifo_reset(dlci->fifo); | |
1416 | } else | |
1417 | dlci->gsm->dead = 1; | |
1418 | wake_up(&dlci->gsm->event); | |
1419 | /* A DLCI 0 close is a MUX termination so we need to kick that | |
1420 | back to userspace somehow */ | |
1421 | } | |
1422 | ||
1423 | /** | |
1424 | * gsm_dlci_open - a DLCI has opened | |
1425 | * @dlci: DLCI that opened | |
1426 | * | |
1427 | * Perform processing when moving a DLCI into open state. | |
1428 | */ | |
1429 | ||
1430 | static void gsm_dlci_open(struct gsm_dlci *dlci) | |
1431 | { | |
1432 | /* Note that SABM UA .. SABM UA first UA lost can mean that we go | |
1433 | open -> open */ | |
1434 | del_timer(&dlci->t1); | |
1435 | /* This will let a tty open continue */ | |
1436 | dlci->state = DLCI_OPEN; | |
1437 | if (debug & 8) | |
5f9a31d6 | 1438 | pr_debug("DLCI %d goes open.\n", dlci->addr); |
e1eaea46 AC |
1439 | wake_up(&dlci->gsm->event); |
1440 | } | |
1441 | ||
1442 | /** | |
1443 | * gsm_dlci_t1 - T1 timer expiry | |
1444 | * @dlci: DLCI that opened | |
1445 | * | |
1446 | * The T1 timer handles retransmits of control frames (essentially of | |
1447 | * SABM and DISC). We resend the command until the retry count runs out | |
1448 | * in which case an opening port goes back to closed and a closing port | |
1449 | * is simply put into closed state (any further frames from the other | |
1450 | * end will get a DM response) | |
1451 | */ | |
1452 | ||
1453 | static void gsm_dlci_t1(unsigned long data) | |
1454 | { | |
1455 | struct gsm_dlci *dlci = (struct gsm_dlci *)data; | |
1456 | struct gsm_mux *gsm = dlci->gsm; | |
1457 | ||
1458 | switch (dlci->state) { | |
1459 | case DLCI_OPENING: | |
1460 | dlci->retries--; | |
1461 | if (dlci->retries) { | |
1462 | gsm_command(dlci->gsm, dlci->addr, SABM|PF); | |
1463 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | |
1464 | } else | |
1465 | gsm_dlci_close(dlci); | |
1466 | break; | |
1467 | case DLCI_CLOSING: | |
1468 | dlci->retries--; | |
1469 | if (dlci->retries) { | |
1470 | gsm_command(dlci->gsm, dlci->addr, DISC|PF); | |
1471 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | |
1472 | } else | |
1473 | gsm_dlci_close(dlci); | |
1474 | break; | |
1475 | } | |
1476 | } | |
1477 | ||
1478 | /** | |
1479 | * gsm_dlci_begin_open - start channel open procedure | |
1480 | * @dlci: DLCI to open | |
1481 | * | |
1482 | * Commence opening a DLCI from the Linux side. We issue SABM messages | |
1483 | * to the modem which should then reply with a UA, at which point we | |
1484 | * will move into open state. Opening is done asynchronously with retry | |
1485 | * running off timers and the responses. | |
1486 | */ | |
1487 | ||
1488 | static void gsm_dlci_begin_open(struct gsm_dlci *dlci) | |
1489 | { | |
1490 | struct gsm_mux *gsm = dlci->gsm; | |
1491 | if (dlci->state == DLCI_OPEN || dlci->state == DLCI_OPENING) | |
1492 | return; | |
1493 | dlci->retries = gsm->n2; | |
1494 | dlci->state = DLCI_OPENING; | |
1495 | gsm_command(dlci->gsm, dlci->addr, SABM|PF); | |
1496 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | |
1497 | } | |
1498 | ||
1499 | /** | |
1500 | * gsm_dlci_begin_close - start channel open procedure | |
1501 | * @dlci: DLCI to open | |
1502 | * | |
1503 | * Commence closing a DLCI from the Linux side. We issue DISC messages | |
1504 | * to the modem which should then reply with a UA, at which point we | |
1505 | * will move into closed state. Closing is done asynchronously with retry | |
1506 | * off timers. We may also receive a DM reply from the other end which | |
1507 | * indicates the channel was already closed. | |
1508 | */ | |
1509 | ||
1510 | static void gsm_dlci_begin_close(struct gsm_dlci *dlci) | |
1511 | { | |
1512 | struct gsm_mux *gsm = dlci->gsm; | |
1513 | if (dlci->state == DLCI_CLOSED || dlci->state == DLCI_CLOSING) | |
1514 | return; | |
1515 | dlci->retries = gsm->n2; | |
1516 | dlci->state = DLCI_CLOSING; | |
1517 | gsm_command(dlci->gsm, dlci->addr, DISC|PF); | |
1518 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | |
1519 | } | |
1520 | ||
1521 | /** | |
1522 | * gsm_dlci_data - data arrived | |
1523 | * @dlci: channel | |
1524 | * @data: block of bytes received | |
1525 | * @len: length of received block | |
1526 | * | |
1527 | * A UI or UIH frame has arrived which contains data for a channel | |
1528 | * other than the control channel. If the relevant virtual tty is | |
1529 | * open we shovel the bits down it, if not we drop them. | |
1530 | */ | |
1531 | ||
7263287a | 1532 | static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int clen) |
e1eaea46 AC |
1533 | { |
1534 | /* krefs .. */ | |
1535 | struct tty_port *port = &dlci->port; | |
1536 | struct tty_struct *tty = tty_port_tty_get(port); | |
1537 | unsigned int modem = 0; | |
7263287a | 1538 | int len = clen; |
e1eaea46 AC |
1539 | |
1540 | if (debug & 16) | |
5f9a31d6 | 1541 | pr_debug("%d bytes for tty %p\n", len, tty); |
e1eaea46 AC |
1542 | if (tty) { |
1543 | switch (dlci->adaption) { | |
5f9a31d6 AC |
1544 | /* Unsupported types */ |
1545 | /* Packetised interruptible data */ | |
1546 | case 4: | |
1547 | break; | |
1548 | /* Packetised uininterruptible voice/data */ | |
1549 | case 3: | |
1550 | break; | |
1551 | /* Asynchronous serial with line state in each frame */ | |
1552 | case 2: | |
1553 | while (gsm_read_ea(&modem, *data++) == 0) { | |
1554 | len--; | |
1555 | if (len == 0) | |
1556 | return; | |
1557 | } | |
7263287a | 1558 | gsm_process_modem(tty, dlci, modem, clen); |
5f9a31d6 AC |
1559 | /* Line state will go via DLCI 0 controls only */ |
1560 | case 1: | |
1561 | default: | |
1562 | tty_insert_flip_string(tty, data, len); | |
1563 | tty_flip_buffer_push(tty); | |
e1eaea46 AC |
1564 | } |
1565 | tty_kref_put(tty); | |
1566 | } | |
1567 | } | |
1568 | ||
1569 | /** | |
1570 | * gsm_dlci_control - data arrived on control channel | |
1571 | * @dlci: channel | |
1572 | * @data: block of bytes received | |
1573 | * @len: length of received block | |
1574 | * | |
1575 | * A UI or UIH frame has arrived which contains data for DLCI 0 the | |
1576 | * control channel. This should contain a command EA followed by | |
1577 | * control data bytes. The command EA contains a command/response bit | |
1578 | * and we divide up the work accordingly. | |
1579 | */ | |
1580 | ||
1581 | static void gsm_dlci_command(struct gsm_dlci *dlci, u8 *data, int len) | |
1582 | { | |
1583 | /* See what command is involved */ | |
1584 | unsigned int command = 0; | |
1585 | while (len-- > 0) { | |
1586 | if (gsm_read_ea(&command, *data++) == 1) { | |
1587 | int clen = *data++; | |
1588 | len--; | |
1589 | /* FIXME: this is properly an EA */ | |
1590 | clen >>= 1; | |
1591 | /* Malformed command ? */ | |
1592 | if (clen > len) | |
1593 | return; | |
1594 | if (command & 1) | |
1595 | gsm_control_message(dlci->gsm, command, | |
1596 | data, clen); | |
1597 | else | |
1598 | gsm_control_response(dlci->gsm, command, | |
1599 | data, clen); | |
1600 | return; | |
1601 | } | |
1602 | } | |
1603 | } | |
1604 | ||
1605 | /* | |
1606 | * Allocate/Free DLCI channels | |
1607 | */ | |
1608 | ||
1609 | /** | |
1610 | * gsm_dlci_alloc - allocate a DLCI | |
1611 | * @gsm: GSM mux | |
1612 | * @addr: address of the DLCI | |
1613 | * | |
1614 | * Allocate and install a new DLCI object into the GSM mux. | |
1615 | * | |
1616 | * FIXME: review locking races | |
1617 | */ | |
1618 | ||
1619 | static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr) | |
1620 | { | |
1621 | struct gsm_dlci *dlci = kzalloc(sizeof(struct gsm_dlci), GFP_ATOMIC); | |
1622 | if (dlci == NULL) | |
1623 | return NULL; | |
1624 | spin_lock_init(&dlci->lock); | |
6ab8fba7 | 1625 | kref_init(&dlci->ref); |
bcd5abe2 | 1626 | mutex_init(&dlci->mutex); |
e1eaea46 AC |
1627 | dlci->fifo = &dlci->_fifo; |
1628 | if (kfifo_alloc(&dlci->_fifo, 4096, GFP_KERNEL) < 0) { | |
1629 | kfree(dlci); | |
1630 | return NULL; | |
1631 | } | |
1632 | ||
1633 | skb_queue_head_init(&dlci->skb_list); | |
1634 | init_timer(&dlci->t1); | |
1635 | dlci->t1.function = gsm_dlci_t1; | |
1636 | dlci->t1.data = (unsigned long)dlci; | |
1637 | tty_port_init(&dlci->port); | |
1638 | dlci->port.ops = &gsm_port_ops; | |
1639 | dlci->gsm = gsm; | |
1640 | dlci->addr = addr; | |
1641 | dlci->adaption = gsm->adaption; | |
1642 | dlci->state = DLCI_CLOSED; | |
1643 | if (addr) | |
1644 | dlci->data = gsm_dlci_data; | |
1645 | else | |
1646 | dlci->data = gsm_dlci_command; | |
1647 | gsm->dlci[addr] = dlci; | |
1648 | return dlci; | |
1649 | } | |
1650 | ||
1651 | /** | |
6ab8fba7 RG |
1652 | * gsm_dlci_free - free DLCI |
1653 | * @dlci: DLCI to free | |
1654 | * | |
1655 | * Free up a DLCI. | |
1656 | * | |
1657 | * Can sleep. | |
1658 | */ | |
1659 | static void gsm_dlci_free(struct kref *ref) | |
1660 | { | |
1661 | struct gsm_dlci *dlci = container_of(ref, struct gsm_dlci, ref); | |
1662 | ||
1663 | del_timer_sync(&dlci->t1); | |
1664 | dlci->gsm->dlci[dlci->addr] = NULL; | |
1665 | kfifo_free(dlci->fifo); | |
1666 | while ((dlci->skb = skb_dequeue(&dlci->skb_list))) | |
1667 | kfree_skb(dlci->skb); | |
1668 | kfree(dlci); | |
1669 | } | |
1670 | ||
1671 | static inline void dlci_get(struct gsm_dlci *dlci) | |
1672 | { | |
1673 | kref_get(&dlci->ref); | |
1674 | } | |
1675 | ||
1676 | static inline void dlci_put(struct gsm_dlci *dlci) | |
1677 | { | |
1678 | kref_put(&dlci->ref, gsm_dlci_free); | |
1679 | } | |
1680 | ||
1681 | /** | |
1682 | * gsm_dlci_release - release DLCI | |
e1eaea46 AC |
1683 | * @dlci: DLCI to destroy |
1684 | * | |
6ab8fba7 RG |
1685 | * Release a DLCI. Actual free is deferred until either |
1686 | * mux is closed or tty is closed - whichever is last. | |
e1eaea46 AC |
1687 | * |
1688 | * Can sleep. | |
1689 | */ | |
6ab8fba7 | 1690 | static void gsm_dlci_release(struct gsm_dlci *dlci) |
e1eaea46 AC |
1691 | { |
1692 | struct tty_struct *tty = tty_port_tty_get(&dlci->port); | |
1693 | if (tty) { | |
1694 | tty_vhangup(tty); | |
1695 | tty_kref_put(tty); | |
1696 | } | |
6ab8fba7 | 1697 | dlci_put(dlci); |
e1eaea46 AC |
1698 | } |
1699 | ||
e1eaea46 AC |
1700 | /* |
1701 | * LAPBish link layer logic | |
1702 | */ | |
1703 | ||
1704 | /** | |
1705 | * gsm_queue - a GSM frame is ready to process | |
1706 | * @gsm: pointer to our gsm mux | |
1707 | * | |
1708 | * At this point in time a frame has arrived and been demangled from | |
1709 | * the line encoding. All the differences between the encodings have | |
1710 | * been handled below us and the frame is unpacked into the structures. | |
1711 | * The fcs holds the header FCS but any data FCS must be added here. | |
1712 | */ | |
1713 | ||
1714 | static void gsm_queue(struct gsm_mux *gsm) | |
1715 | { | |
1716 | struct gsm_dlci *dlci; | |
1717 | u8 cr; | |
1718 | int address; | |
1719 | /* We have to sneak a look at the packet body to do the FCS. | |
1720 | A somewhat layering violation in the spec */ | |
1721 | ||
1722 | if ((gsm->control & ~PF) == UI) | |
1723 | gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len); | |
9db4e438 MK |
1724 | if (gsm->encoding == 0){ |
1725 | /* WARNING: gsm->received_fcs is used for gsm->encoding = 0 only. | |
1726 | In this case it contain the last piece of data | |
1727 | required to generate final CRC */ | |
1728 | gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs); | |
1729 | } | |
e1eaea46 AC |
1730 | if (gsm->fcs != GOOD_FCS) { |
1731 | gsm->bad_fcs++; | |
1732 | if (debug & 4) | |
5f9a31d6 | 1733 | pr_debug("BAD FCS %02x\n", gsm->fcs); |
e1eaea46 AC |
1734 | return; |
1735 | } | |
1736 | address = gsm->address >> 1; | |
1737 | if (address >= NUM_DLCI) | |
1738 | goto invalid; | |
1739 | ||
1740 | cr = gsm->address & 1; /* C/R bit */ | |
1741 | ||
1742 | gsm_print_packet("<--", address, cr, gsm->control, gsm->buf, gsm->len); | |
1743 | ||
1744 | cr ^= 1 - gsm->initiator; /* Flip so 1 always means command */ | |
1745 | dlci = gsm->dlci[address]; | |
1746 | ||
1747 | switch (gsm->control) { | |
1748 | case SABM|PF: | |
1749 | if (cr == 0) | |
1750 | goto invalid; | |
1751 | if (dlci == NULL) | |
1752 | dlci = gsm_dlci_alloc(gsm, address); | |
1753 | if (dlci == NULL) | |
1754 | return; | |
1755 | if (dlci->dead) | |
1756 | gsm_response(gsm, address, DM); | |
1757 | else { | |
1758 | gsm_response(gsm, address, UA); | |
1759 | gsm_dlci_open(dlci); | |
1760 | } | |
1761 | break; | |
1762 | case DISC|PF: | |
1763 | if (cr == 0) | |
1764 | goto invalid; | |
1765 | if (dlci == NULL || dlci->state == DLCI_CLOSED) { | |
1766 | gsm_response(gsm, address, DM); | |
1767 | return; | |
1768 | } | |
1769 | /* Real close complete */ | |
1770 | gsm_response(gsm, address, UA); | |
1771 | gsm_dlci_close(dlci); | |
1772 | break; | |
1773 | case UA: | |
1774 | case UA|PF: | |
1775 | if (cr == 0 || dlci == NULL) | |
1776 | break; | |
1777 | switch (dlci->state) { | |
1778 | case DLCI_CLOSING: | |
1779 | gsm_dlci_close(dlci); | |
1780 | break; | |
1781 | case DLCI_OPENING: | |
1782 | gsm_dlci_open(dlci); | |
1783 | break; | |
1784 | } | |
1785 | break; | |
1786 | case DM: /* DM can be valid unsolicited */ | |
1787 | case DM|PF: | |
1788 | if (cr) | |
1789 | goto invalid; | |
1790 | if (dlci == NULL) | |
1791 | return; | |
1792 | gsm_dlci_close(dlci); | |
1793 | break; | |
1794 | case UI: | |
1795 | case UI|PF: | |
1796 | case UIH: | |
1797 | case UIH|PF: | |
1798 | #if 0 | |
1799 | if (cr) | |
1800 | goto invalid; | |
1801 | #endif | |
1802 | if (dlci == NULL || dlci->state != DLCI_OPEN) { | |
1803 | gsm_command(gsm, address, DM|PF); | |
1804 | return; | |
1805 | } | |
1806 | dlci->data(dlci, gsm->buf, gsm->len); | |
1807 | break; | |
1808 | default: | |
1809 | goto invalid; | |
1810 | } | |
1811 | return; | |
1812 | invalid: | |
1813 | gsm->malformed++; | |
1814 | return; | |
1815 | } | |
1816 | ||
1817 | ||
1818 | /** | |
1819 | * gsm0_receive - perform processing for non-transparency | |
1820 | * @gsm: gsm data for this ldisc instance | |
1821 | * @c: character | |
1822 | * | |
1823 | * Receive bytes in gsm mode 0 | |
1824 | */ | |
1825 | ||
1826 | static void gsm0_receive(struct gsm_mux *gsm, unsigned char c) | |
1827 | { | |
c2f2f000 AC |
1828 | unsigned int len; |
1829 | ||
e1eaea46 AC |
1830 | switch (gsm->state) { |
1831 | case GSM_SEARCH: /* SOF marker */ | |
1832 | if (c == GSM0_SOF) { | |
1833 | gsm->state = GSM_ADDRESS; | |
1834 | gsm->address = 0; | |
1835 | gsm->len = 0; | |
1836 | gsm->fcs = INIT_FCS; | |
1837 | } | |
c2f2f000 AC |
1838 | break; |
1839 | case GSM_ADDRESS: /* Address EA */ | |
e1eaea46 AC |
1840 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); |
1841 | if (gsm_read_ea(&gsm->address, c)) | |
1842 | gsm->state = GSM_CONTROL; | |
1843 | break; | |
1844 | case GSM_CONTROL: /* Control Byte */ | |
1845 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | |
1846 | gsm->control = c; | |
c2f2f000 | 1847 | gsm->state = GSM_LEN0; |
e1eaea46 | 1848 | break; |
c2f2f000 | 1849 | case GSM_LEN0: /* Length EA */ |
e1eaea46 AC |
1850 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); |
1851 | if (gsm_read_ea(&gsm->len, c)) { | |
1852 | if (gsm->len > gsm->mru) { | |
1853 | gsm->bad_size++; | |
1854 | gsm->state = GSM_SEARCH; | |
1855 | break; | |
1856 | } | |
1857 | gsm->count = 0; | |
c2f2f000 AC |
1858 | if (!gsm->len) |
1859 | gsm->state = GSM_FCS; | |
1860 | else | |
1861 | gsm->state = GSM_DATA; | |
1862 | break; | |
e1eaea46 | 1863 | } |
c2f2f000 AC |
1864 | gsm->state = GSM_LEN1; |
1865 | break; | |
1866 | case GSM_LEN1: | |
1867 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | |
1868 | len = c; | |
1869 | gsm->len |= len << 7; | |
1870 | if (gsm->len > gsm->mru) { | |
1871 | gsm->bad_size++; | |
1872 | gsm->state = GSM_SEARCH; | |
1873 | break; | |
e1eaea46 | 1874 | } |
c2f2f000 AC |
1875 | gsm->count = 0; |
1876 | if (!gsm->len) | |
1877 | gsm->state = GSM_FCS; | |
1878 | else | |
1879 | gsm->state = GSM_DATA; | |
e1eaea46 AC |
1880 | break; |
1881 | case GSM_DATA: /* Data */ | |
1882 | gsm->buf[gsm->count++] = c; | |
1883 | if (gsm->count == gsm->len) | |
1884 | gsm->state = GSM_FCS; | |
1885 | break; | |
1886 | case GSM_FCS: /* FCS follows the packet */ | |
c2f2f000 | 1887 | gsm->received_fcs = c; |
e1eaea46 | 1888 | gsm_queue(gsm); |
c2f2f000 AC |
1889 | gsm->state = GSM_SSOF; |
1890 | break; | |
1891 | case GSM_SSOF: | |
1892 | if (c == GSM0_SOF) { | |
1893 | gsm->state = GSM_SEARCH; | |
1894 | break; | |
1895 | } | |
e1eaea46 AC |
1896 | break; |
1897 | } | |
1898 | } | |
1899 | ||
1900 | /** | |
c2f2f000 | 1901 | * gsm1_receive - perform processing for non-transparency |
e1eaea46 AC |
1902 | * @gsm: gsm data for this ldisc instance |
1903 | * @c: character | |
1904 | * | |
1905 | * Receive bytes in mode 1 (Advanced option) | |
1906 | */ | |
1907 | ||
1908 | static void gsm1_receive(struct gsm_mux *gsm, unsigned char c) | |
1909 | { | |
1910 | if (c == GSM1_SOF) { | |
1911 | /* EOF is only valid in frame if we have got to the data state | |
1912 | and received at least one byte (the FCS) */ | |
1913 | if (gsm->state == GSM_DATA && gsm->count) { | |
1914 | /* Extract the FCS */ | |
1915 | gsm->count--; | |
1916 | gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->buf[gsm->count]); | |
1917 | gsm->len = gsm->count; | |
1918 | gsm_queue(gsm); | |
1919 | gsm->state = GSM_START; | |
1920 | return; | |
1921 | } | |
1922 | /* Any partial frame was a runt so go back to start */ | |
1923 | if (gsm->state != GSM_START) { | |
1924 | gsm->malformed++; | |
1925 | gsm->state = GSM_START; | |
1926 | } | |
1927 | /* A SOF in GSM_START means we are still reading idling or | |
1928 | framing bytes */ | |
1929 | return; | |
1930 | } | |
1931 | ||
1932 | if (c == GSM1_ESCAPE) { | |
1933 | gsm->escape = 1; | |
1934 | return; | |
1935 | } | |
1936 | ||
1937 | /* Only an unescaped SOF gets us out of GSM search */ | |
1938 | if (gsm->state == GSM_SEARCH) | |
1939 | return; | |
1940 | ||
1941 | if (gsm->escape) { | |
1942 | c ^= GSM1_ESCAPE_BITS; | |
1943 | gsm->escape = 0; | |
1944 | } | |
1945 | switch (gsm->state) { | |
1946 | case GSM_START: /* First byte after SOF */ | |
1947 | gsm->address = 0; | |
1948 | gsm->state = GSM_ADDRESS; | |
1949 | gsm->fcs = INIT_FCS; | |
1950 | /* Drop through */ | |
1951 | case GSM_ADDRESS: /* Address continuation */ | |
1952 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | |
1953 | if (gsm_read_ea(&gsm->address, c)) | |
1954 | gsm->state = GSM_CONTROL; | |
1955 | break; | |
1956 | case GSM_CONTROL: /* Control Byte */ | |
1957 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | |
1958 | gsm->control = c; | |
1959 | gsm->count = 0; | |
1960 | gsm->state = GSM_DATA; | |
1961 | break; | |
1962 | case GSM_DATA: /* Data */ | |
5f9a31d6 | 1963 | if (gsm->count > gsm->mru) { /* Allow one for the FCS */ |
e1eaea46 AC |
1964 | gsm->state = GSM_OVERRUN; |
1965 | gsm->bad_size++; | |
1966 | } else | |
1967 | gsm->buf[gsm->count++] = c; | |
1968 | break; | |
1969 | case GSM_OVERRUN: /* Over-long - eg a dropped SOF */ | |
1970 | break; | |
1971 | } | |
1972 | } | |
1973 | ||
1974 | /** | |
1975 | * gsm_error - handle tty error | |
1976 | * @gsm: ldisc data | |
1977 | * @data: byte received (may be invalid) | |
1978 | * @flag: error received | |
1979 | * | |
1980 | * Handle an error in the receipt of data for a frame. Currently we just | |
1981 | * go back to hunting for a SOF. | |
1982 | * | |
1983 | * FIXME: better diagnostics ? | |
1984 | */ | |
1985 | ||
1986 | static void gsm_error(struct gsm_mux *gsm, | |
1987 | unsigned char data, unsigned char flag) | |
1988 | { | |
1989 | gsm->state = GSM_SEARCH; | |
1990 | gsm->io_error++; | |
1991 | } | |
1992 | ||
1993 | /** | |
1994 | * gsm_cleanup_mux - generic GSM protocol cleanup | |
1995 | * @gsm: our mux | |
1996 | * | |
1997 | * Clean up the bits of the mux which are the same for all framing | |
1998 | * protocols. Remove the mux from the mux table, stop all the timers | |
1999 | * and then shut down each device hanging up the channels as we go. | |
2000 | */ | |
2001 | ||
2002 | void gsm_cleanup_mux(struct gsm_mux *gsm) | |
2003 | { | |
2004 | int i; | |
2005 | struct gsm_dlci *dlci = gsm->dlci[0]; | |
2006 | struct gsm_msg *txq; | |
2007 | ||
2008 | gsm->dead = 1; | |
2009 | ||
2010 | spin_lock(&gsm_mux_lock); | |
2011 | for (i = 0; i < MAX_MUX; i++) { | |
2012 | if (gsm_mux[i] == gsm) { | |
2013 | gsm_mux[i] = NULL; | |
2014 | break; | |
2015 | } | |
2016 | } | |
2017 | spin_unlock(&gsm_mux_lock); | |
2018 | WARN_ON(i == MAX_MUX); | |
2019 | ||
2020 | del_timer_sync(&gsm->t2_timer); | |
2021 | /* Now we are sure T2 has stopped */ | |
2022 | if (dlci) { | |
2023 | dlci->dead = 1; | |
2024 | gsm_dlci_begin_close(dlci); | |
2025 | wait_event_interruptible(gsm->event, | |
2026 | dlci->state == DLCI_CLOSED); | |
2027 | } | |
2028 | /* Free up any link layer users */ | |
2029 | for (i = 0; i < NUM_DLCI; i++) | |
2030 | if (gsm->dlci[i]) | |
6ab8fba7 | 2031 | gsm_dlci_release(gsm->dlci[i]); |
e1eaea46 AC |
2032 | /* Now wipe the queues */ |
2033 | for (txq = gsm->tx_head; txq != NULL; txq = gsm->tx_head) { | |
2034 | gsm->tx_head = txq->next; | |
2035 | kfree(txq); | |
2036 | } | |
2037 | gsm->tx_tail = NULL; | |
2038 | } | |
2039 | EXPORT_SYMBOL_GPL(gsm_cleanup_mux); | |
2040 | ||
2041 | /** | |
2042 | * gsm_activate_mux - generic GSM setup | |
2043 | * @gsm: our mux | |
2044 | * | |
2045 | * Set up the bits of the mux which are the same for all framing | |
2046 | * protocols. Add the mux to the mux table so it can be opened and | |
2047 | * finally kick off connecting to DLCI 0 on the modem. | |
2048 | */ | |
2049 | ||
2050 | int gsm_activate_mux(struct gsm_mux *gsm) | |
2051 | { | |
2052 | struct gsm_dlci *dlci; | |
2053 | int i = 0; | |
2054 | ||
2055 | init_timer(&gsm->t2_timer); | |
2056 | gsm->t2_timer.function = gsm_control_retransmit; | |
2057 | gsm->t2_timer.data = (unsigned long)gsm; | |
2058 | init_waitqueue_head(&gsm->event); | |
2059 | spin_lock_init(&gsm->control_lock); | |
2060 | spin_lock_init(&gsm->tx_lock); | |
2061 | ||
2062 | if (gsm->encoding == 0) | |
2063 | gsm->receive = gsm0_receive; | |
2064 | else | |
2065 | gsm->receive = gsm1_receive; | |
2066 | gsm->error = gsm_error; | |
2067 | ||
2068 | spin_lock(&gsm_mux_lock); | |
2069 | for (i = 0; i < MAX_MUX; i++) { | |
2070 | if (gsm_mux[i] == NULL) { | |
d50f6dca | 2071 | gsm->num = i; |
e1eaea46 AC |
2072 | gsm_mux[i] = gsm; |
2073 | break; | |
2074 | } | |
2075 | } | |
2076 | spin_unlock(&gsm_mux_lock); | |
2077 | if (i == MAX_MUX) | |
2078 | return -EBUSY; | |
2079 | ||
2080 | dlci = gsm_dlci_alloc(gsm, 0); | |
2081 | if (dlci == NULL) | |
2082 | return -ENOMEM; | |
2083 | gsm->dead = 0; /* Tty opens are now permissible */ | |
2084 | return 0; | |
2085 | } | |
2086 | EXPORT_SYMBOL_GPL(gsm_activate_mux); | |
2087 | ||
2088 | /** | |
2089 | * gsm_free_mux - free up a mux | |
2090 | * @mux: mux to free | |
2091 | * | |
6ab8fba7 | 2092 | * Dispose of allocated resources for a dead mux |
e1eaea46 AC |
2093 | */ |
2094 | void gsm_free_mux(struct gsm_mux *gsm) | |
2095 | { | |
2096 | kfree(gsm->txframe); | |
2097 | kfree(gsm->buf); | |
2098 | kfree(gsm); | |
2099 | } | |
2100 | EXPORT_SYMBOL_GPL(gsm_free_mux); | |
2101 | ||
6ab8fba7 RG |
2102 | /** |
2103 | * gsm_free_muxr - free up a mux | |
2104 | * @mux: mux to free | |
2105 | * | |
2106 | * Dispose of allocated resources for a dead mux | |
2107 | */ | |
2108 | static void gsm_free_muxr(struct kref *ref) | |
2109 | { | |
2110 | struct gsm_mux *gsm = container_of(ref, struct gsm_mux, ref); | |
2111 | gsm_free_mux(gsm); | |
2112 | } | |
2113 | ||
2114 | static inline void mux_get(struct gsm_mux *gsm) | |
2115 | { | |
2116 | kref_get(&gsm->ref); | |
2117 | } | |
2118 | ||
2119 | static inline void mux_put(struct gsm_mux *gsm) | |
2120 | { | |
2121 | kref_put(&gsm->ref, gsm_free_muxr); | |
2122 | } | |
2123 | ||
e1eaea46 AC |
2124 | /** |
2125 | * gsm_alloc_mux - allocate a mux | |
2126 | * | |
2127 | * Creates a new mux ready for activation. | |
2128 | */ | |
2129 | ||
2130 | struct gsm_mux *gsm_alloc_mux(void) | |
2131 | { | |
2132 | struct gsm_mux *gsm = kzalloc(sizeof(struct gsm_mux), GFP_KERNEL); | |
2133 | if (gsm == NULL) | |
2134 | return NULL; | |
2135 | gsm->buf = kmalloc(MAX_MRU + 1, GFP_KERNEL); | |
2136 | if (gsm->buf == NULL) { | |
2137 | kfree(gsm); | |
2138 | return NULL; | |
2139 | } | |
2140 | gsm->txframe = kmalloc(2 * MAX_MRU + 2, GFP_KERNEL); | |
2141 | if (gsm->txframe == NULL) { | |
2142 | kfree(gsm->buf); | |
2143 | kfree(gsm); | |
2144 | return NULL; | |
2145 | } | |
2146 | spin_lock_init(&gsm->lock); | |
6ab8fba7 | 2147 | kref_init(&gsm->ref); |
e1eaea46 AC |
2148 | |
2149 | gsm->t1 = T1; | |
2150 | gsm->t2 = T2; | |
2151 | gsm->n2 = N2; | |
2152 | gsm->ftype = UIH; | |
e1eaea46 AC |
2153 | gsm->adaption = 1; |
2154 | gsm->encoding = 1; | |
2155 | gsm->mru = 64; /* Default to encoding 1 so these should be 64 */ | |
2156 | gsm->mtu = 64; | |
2157 | gsm->dead = 1; /* Avoid early tty opens */ | |
2158 | ||
2159 | return gsm; | |
2160 | } | |
2161 | EXPORT_SYMBOL_GPL(gsm_alloc_mux); | |
2162 | ||
e1eaea46 AC |
2163 | /** |
2164 | * gsmld_output - write to link | |
2165 | * @gsm: our mux | |
2166 | * @data: bytes to output | |
2167 | * @len: size | |
2168 | * | |
2169 | * Write a block of data from the GSM mux to the data channel. This | |
2170 | * will eventually be serialized from above but at the moment isn't. | |
2171 | */ | |
2172 | ||
2173 | static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len) | |
2174 | { | |
2175 | if (tty_write_room(gsm->tty) < len) { | |
2176 | set_bit(TTY_DO_WRITE_WAKEUP, &gsm->tty->flags); | |
2177 | return -ENOSPC; | |
2178 | } | |
0a77c4f9 JP |
2179 | if (debug & 4) |
2180 | print_hex_dump_bytes("gsmld_output: ", DUMP_PREFIX_OFFSET, | |
2181 | data, len); | |
e1eaea46 AC |
2182 | gsm->tty->ops->write(gsm->tty, data, len); |
2183 | return len; | |
2184 | } | |
2185 | ||
2186 | /** | |
2187 | * gsmld_attach_gsm - mode set up | |
2188 | * @tty: our tty structure | |
2189 | * @gsm: our mux | |
2190 | * | |
2191 | * Set up the MUX for basic mode and commence connecting to the | |
2192 | * modem. Currently called from the line discipline set up but | |
2193 | * will need moving to an ioctl path. | |
2194 | */ | |
2195 | ||
2196 | static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) | |
2197 | { | |
d50f6dca RG |
2198 | int ret, i; |
2199 | int base = gsm->num << 6; /* Base for this MUX */ | |
e1eaea46 AC |
2200 | |
2201 | gsm->tty = tty_kref_get(tty); | |
2202 | gsm->output = gsmld_output; | |
2203 | ret = gsm_activate_mux(gsm); | |
2204 | if (ret != 0) | |
2205 | tty_kref_put(gsm->tty); | |
d50f6dca RG |
2206 | else { |
2207 | /* Don't register device 0 - this is the control channel and not | |
2208 | a usable tty interface */ | |
2209 | for (i = 1; i < NUM_DLCI; i++) | |
2210 | tty_register_device(gsm_tty_driver, base + i, NULL); | |
2211 | } | |
e1eaea46 AC |
2212 | return ret; |
2213 | } | |
2214 | ||
2215 | ||
2216 | /** | |
2217 | * gsmld_detach_gsm - stop doing 0710 mux | |
70f23fd6 | 2218 | * @tty: tty attached to the mux |
e1eaea46 AC |
2219 | * @gsm: mux |
2220 | * | |
2221 | * Shutdown and then clean up the resources used by the line discipline | |
2222 | */ | |
2223 | ||
2224 | static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) | |
2225 | { | |
d50f6dca RG |
2226 | int i; |
2227 | int base = gsm->num << 6; /* Base for this MUX */ | |
2228 | ||
e1eaea46 | 2229 | WARN_ON(tty != gsm->tty); |
d50f6dca RG |
2230 | for (i = 1; i < NUM_DLCI; i++) |
2231 | tty_unregister_device(gsm_tty_driver, base + i); | |
e1eaea46 AC |
2232 | gsm_cleanup_mux(gsm); |
2233 | tty_kref_put(gsm->tty); | |
2234 | gsm->tty = NULL; | |
2235 | } | |
2236 | ||
55db4c64 LT |
2237 | static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
2238 | char *fp, int count) | |
e1eaea46 AC |
2239 | { |
2240 | struct gsm_mux *gsm = tty->disc_data; | |
2241 | const unsigned char *dp; | |
2242 | char *f; | |
2243 | int i; | |
2244 | char buf[64]; | |
2245 | char flags; | |
2246 | ||
0a77c4f9 JP |
2247 | if (debug & 4) |
2248 | print_hex_dump_bytes("gsmld_receive: ", DUMP_PREFIX_OFFSET, | |
2249 | cp, count); | |
e1eaea46 AC |
2250 | |
2251 | for (i = count, dp = cp, f = fp; i; i--, dp++) { | |
2252 | flags = *f++; | |
2253 | switch (flags) { | |
2254 | case TTY_NORMAL: | |
2255 | gsm->receive(gsm, *dp); | |
2256 | break; | |
2257 | case TTY_OVERRUN: | |
2258 | case TTY_BREAK: | |
2259 | case TTY_PARITY: | |
2260 | case TTY_FRAME: | |
2261 | gsm->error(gsm, *dp, flags); | |
2262 | break; | |
2263 | default: | |
5f9a31d6 | 2264 | WARN_ONCE("%s: unknown flag %d\n", |
e1eaea46 AC |
2265 | tty_name(tty, buf), flags); |
2266 | break; | |
2267 | } | |
2268 | } | |
2269 | /* FASYNC if needed ? */ | |
2270 | /* If clogged call tty_throttle(tty); */ | |
2271 | } | |
2272 | ||
2273 | /** | |
2274 | * gsmld_chars_in_buffer - report available bytes | |
2275 | * @tty: tty device | |
2276 | * | |
2277 | * Report the number of characters buffered to be delivered to user | |
2278 | * at this instant in time. | |
2279 | * | |
2280 | * Locking: gsm lock | |
2281 | */ | |
2282 | ||
2283 | static ssize_t gsmld_chars_in_buffer(struct tty_struct *tty) | |
2284 | { | |
2285 | return 0; | |
2286 | } | |
2287 | ||
2288 | /** | |
2289 | * gsmld_flush_buffer - clean input queue | |
2290 | * @tty: terminal device | |
2291 | * | |
2292 | * Flush the input buffer. Called when the line discipline is | |
2293 | * being closed, when the tty layer wants the buffer flushed (eg | |
2294 | * at hangup). | |
2295 | */ | |
2296 | ||
2297 | static void gsmld_flush_buffer(struct tty_struct *tty) | |
2298 | { | |
2299 | } | |
2300 | ||
2301 | /** | |
2302 | * gsmld_close - close the ldisc for this tty | |
2303 | * @tty: device | |
2304 | * | |
2305 | * Called from the terminal layer when this line discipline is | |
2306 | * being shut down, either because of a close or becsuse of a | |
2307 | * discipline change. The function will not be called while other | |
2308 | * ldisc methods are in progress. | |
2309 | */ | |
2310 | ||
2311 | static void gsmld_close(struct tty_struct *tty) | |
2312 | { | |
2313 | struct gsm_mux *gsm = tty->disc_data; | |
2314 | ||
2315 | gsmld_detach_gsm(tty, gsm); | |
2316 | ||
2317 | gsmld_flush_buffer(tty); | |
2318 | /* Do other clean up here */ | |
6ab8fba7 | 2319 | mux_put(gsm); |
e1eaea46 AC |
2320 | } |
2321 | ||
2322 | /** | |
2323 | * gsmld_open - open an ldisc | |
2324 | * @tty: terminal to open | |
2325 | * | |
2326 | * Called when this line discipline is being attached to the | |
2327 | * terminal device. Can sleep. Called serialized so that no | |
2328 | * other events will occur in parallel. No further open will occur | |
2329 | * until a close. | |
2330 | */ | |
2331 | ||
2332 | static int gsmld_open(struct tty_struct *tty) | |
2333 | { | |
2334 | struct gsm_mux *gsm; | |
2335 | ||
2336 | if (tty->ops->write == NULL) | |
2337 | return -EINVAL; | |
2338 | ||
2339 | /* Attach our ldisc data */ | |
2340 | gsm = gsm_alloc_mux(); | |
2341 | if (gsm == NULL) | |
2342 | return -ENOMEM; | |
2343 | ||
2344 | tty->disc_data = gsm; | |
2345 | tty->receive_room = 65536; | |
2346 | ||
2347 | /* Attach the initial passive connection */ | |
2348 | gsm->encoding = 1; | |
2349 | return gsmld_attach_gsm(tty, gsm); | |
2350 | } | |
2351 | ||
2352 | /** | |
2353 | * gsmld_write_wakeup - asynchronous I/O notifier | |
2354 | * @tty: tty device | |
2355 | * | |
2356 | * Required for the ptys, serial driver etc. since processes | |
2357 | * that attach themselves to the master and rely on ASYNC | |
2358 | * IO must be woken up | |
2359 | */ | |
2360 | ||
2361 | static void gsmld_write_wakeup(struct tty_struct *tty) | |
2362 | { | |
2363 | struct gsm_mux *gsm = tty->disc_data; | |
328be395 | 2364 | unsigned long flags; |
e1eaea46 AC |
2365 | |
2366 | /* Queue poll */ | |
2367 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); | |
2368 | gsm_data_kick(gsm); | |
328be395 DC |
2369 | if (gsm->tx_bytes < TX_THRESH_LO) { |
2370 | spin_lock_irqsave(&gsm->tx_lock, flags); | |
e1eaea46 | 2371 | gsm_dlci_data_sweep(gsm); |
328be395 DC |
2372 | spin_unlock_irqrestore(&gsm->tx_lock, flags); |
2373 | } | |
e1eaea46 AC |
2374 | } |
2375 | ||
2376 | /** | |
2377 | * gsmld_read - read function for tty | |
2378 | * @tty: tty device | |
2379 | * @file: file object | |
2380 | * @buf: userspace buffer pointer | |
2381 | * @nr: size of I/O | |
2382 | * | |
2383 | * Perform reads for the line discipline. We are guaranteed that the | |
2384 | * line discipline will not be closed under us but we may get multiple | |
2385 | * parallel readers and must handle this ourselves. We may also get | |
2386 | * a hangup. Always called in user context, may sleep. | |
2387 | * | |
2388 | * This code must be sure never to sleep through a hangup. | |
2389 | */ | |
2390 | ||
2391 | static ssize_t gsmld_read(struct tty_struct *tty, struct file *file, | |
2392 | unsigned char __user *buf, size_t nr) | |
2393 | { | |
2394 | return -EOPNOTSUPP; | |
2395 | } | |
2396 | ||
2397 | /** | |
2398 | * gsmld_write - write function for tty | |
2399 | * @tty: tty device | |
2400 | * @file: file object | |
2401 | * @buf: userspace buffer pointer | |
2402 | * @nr: size of I/O | |
2403 | * | |
2404 | * Called when the owner of the device wants to send a frame | |
2405 | * itself (or some other control data). The data is transferred | |
2406 | * as-is and must be properly framed and checksummed as appropriate | |
2407 | * by userspace. Frames are either sent whole or not at all as this | |
2408 | * avoids pain user side. | |
2409 | */ | |
2410 | ||
2411 | static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, | |
2412 | const unsigned char *buf, size_t nr) | |
2413 | { | |
2414 | int space = tty_write_room(tty); | |
2415 | if (space >= nr) | |
2416 | return tty->ops->write(tty, buf, nr); | |
2417 | set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); | |
2418 | return -ENOBUFS; | |
2419 | } | |
2420 | ||
2421 | /** | |
2422 | * gsmld_poll - poll method for N_GSM0710 | |
2423 | * @tty: terminal device | |
2424 | * @file: file accessing it | |
2425 | * @wait: poll table | |
2426 | * | |
2427 | * Called when the line discipline is asked to poll() for data or | |
2428 | * for special events. This code is not serialized with respect to | |
2429 | * other events save open/close. | |
2430 | * | |
2431 | * This code must be sure never to sleep through a hangup. | |
2432 | * Called without the kernel lock held - fine | |
2433 | */ | |
2434 | ||
2435 | static unsigned int gsmld_poll(struct tty_struct *tty, struct file *file, | |
2436 | poll_table *wait) | |
2437 | { | |
2438 | unsigned int mask = 0; | |
2439 | struct gsm_mux *gsm = tty->disc_data; | |
2440 | ||
2441 | poll_wait(file, &tty->read_wait, wait); | |
2442 | poll_wait(file, &tty->write_wait, wait); | |
2443 | if (tty_hung_up_p(file)) | |
2444 | mask |= POLLHUP; | |
2445 | if (!tty_is_writelocked(tty) && tty_write_room(tty) > 0) | |
2446 | mask |= POLLOUT | POLLWRNORM; | |
2447 | if (gsm->dead) | |
2448 | mask |= POLLHUP; | |
2449 | return mask; | |
2450 | } | |
2451 | ||
2452 | static int gsmld_config(struct tty_struct *tty, struct gsm_mux *gsm, | |
2453 | struct gsm_config *c) | |
2454 | { | |
2455 | int need_close = 0; | |
2456 | int need_restart = 0; | |
2457 | ||
2458 | /* Stuff we don't support yet - UI or I frame transport, windowing */ | |
5f9a31d6 | 2459 | if ((c->adaption != 1 && c->adaption != 2) || c->k) |
e1eaea46 AC |
2460 | return -EOPNOTSUPP; |
2461 | /* Check the MRU/MTU range looks sane */ | |
2462 | if (c->mru > MAX_MRU || c->mtu > MAX_MTU || c->mru < 8 || c->mtu < 8) | |
2463 | return -EINVAL; | |
2464 | if (c->n2 < 3) | |
2465 | return -EINVAL; | |
2466 | if (c->encapsulation > 1) /* Basic, advanced, no I */ | |
2467 | return -EINVAL; | |
2468 | if (c->initiator > 1) | |
2469 | return -EINVAL; | |
2470 | if (c->i == 0 || c->i > 2) /* UIH and UI only */ | |
2471 | return -EINVAL; | |
2472 | /* | |
2473 | * See what is needed for reconfiguration | |
2474 | */ | |
2475 | ||
2476 | /* Timing fields */ | |
2477 | if (c->t1 != 0 && c->t1 != gsm->t1) | |
2478 | need_restart = 1; | |
2479 | if (c->t2 != 0 && c->t2 != gsm->t2) | |
2480 | need_restart = 1; | |
2481 | if (c->encapsulation != gsm->encoding) | |
2482 | need_restart = 1; | |
2483 | if (c->adaption != gsm->adaption) | |
2484 | need_restart = 1; | |
2485 | /* Requires care */ | |
2486 | if (c->initiator != gsm->initiator) | |
2487 | need_close = 1; | |
2488 | if (c->mru != gsm->mru) | |
2489 | need_restart = 1; | |
2490 | if (c->mtu != gsm->mtu) | |
2491 | need_restart = 1; | |
2492 | ||
2493 | /* | |
2494 | * Close down what is needed, restart and initiate the new | |
2495 | * configuration | |
2496 | */ | |
2497 | ||
2498 | if (need_close || need_restart) { | |
2499 | gsm_dlci_begin_close(gsm->dlci[0]); | |
2500 | /* This will timeout if the link is down due to N2 expiring */ | |
2501 | wait_event_interruptible(gsm->event, | |
2502 | gsm->dlci[0]->state == DLCI_CLOSED); | |
2503 | if (signal_pending(current)) | |
2504 | return -EINTR; | |
2505 | } | |
2506 | if (need_restart) | |
2507 | gsm_cleanup_mux(gsm); | |
2508 | ||
2509 | gsm->initiator = c->initiator; | |
2510 | gsm->mru = c->mru; | |
91f78f36 | 2511 | gsm->mtu = c->mtu; |
e1eaea46 AC |
2512 | gsm->encoding = c->encapsulation; |
2513 | gsm->adaption = c->adaption; | |
820e62ef | 2514 | gsm->n2 = c->n2; |
e1eaea46 AC |
2515 | |
2516 | if (c->i == 1) | |
2517 | gsm->ftype = UIH; | |
2518 | else if (c->i == 2) | |
2519 | gsm->ftype = UI; | |
2520 | ||
2521 | if (c->t1) | |
2522 | gsm->t1 = c->t1; | |
2523 | if (c->t2) | |
2524 | gsm->t2 = c->t2; | |
2525 | ||
2526 | /* FIXME: We need to separate activation/deactivation from adding | |
2527 | and removing from the mux array */ | |
2528 | if (need_restart) | |
2529 | gsm_activate_mux(gsm); | |
2530 | if (gsm->initiator && need_close) | |
2531 | gsm_dlci_begin_open(gsm->dlci[0]); | |
2532 | return 0; | |
2533 | } | |
2534 | ||
2535 | static int gsmld_ioctl(struct tty_struct *tty, struct file *file, | |
2536 | unsigned int cmd, unsigned long arg) | |
2537 | { | |
2538 | struct gsm_config c; | |
2539 | struct gsm_mux *gsm = tty->disc_data; | |
2540 | ||
2541 | switch (cmd) { | |
2542 | case GSMIOC_GETCONF: | |
2543 | memset(&c, 0, sizeof(c)); | |
2544 | c.adaption = gsm->adaption; | |
2545 | c.encapsulation = gsm->encoding; | |
2546 | c.initiator = gsm->initiator; | |
2547 | c.t1 = gsm->t1; | |
2548 | c.t2 = gsm->t2; | |
2549 | c.t3 = 0; /* Not supported */ | |
2550 | c.n2 = gsm->n2; | |
2551 | if (gsm->ftype == UIH) | |
2552 | c.i = 1; | |
2553 | else | |
2554 | c.i = 2; | |
5f9a31d6 | 2555 | pr_debug("Ftype %d i %d\n", gsm->ftype, c.i); |
e1eaea46 AC |
2556 | c.mru = gsm->mru; |
2557 | c.mtu = gsm->mtu; | |
2558 | c.k = 0; | |
2559 | if (copy_to_user((void *)arg, &c, sizeof(c))) | |
2560 | return -EFAULT; | |
2561 | return 0; | |
2562 | case GSMIOC_SETCONF: | |
2563 | if (copy_from_user(&c, (void *)arg, sizeof(c))) | |
2564 | return -EFAULT; | |
2565 | return gsmld_config(tty, gsm, &c); | |
2566 | default: | |
2567 | return n_tty_ioctl_helper(tty, file, cmd, arg); | |
2568 | } | |
2569 | } | |
2570 | ||
bcd5abe2 RG |
2571 | /* |
2572 | * Network interface | |
2573 | * | |
2574 | */ | |
2575 | ||
2576 | static int gsm_mux_net_open(struct net_device *net) | |
2577 | { | |
2578 | pr_debug("%s called\n", __func__); | |
2579 | netif_start_queue(net); | |
2580 | return 0; | |
2581 | } | |
2582 | ||
2583 | static int gsm_mux_net_close(struct net_device *net) | |
2584 | { | |
2585 | netif_stop_queue(net); | |
2586 | return 0; | |
2587 | } | |
2588 | ||
2589 | static struct net_device_stats *gsm_mux_net_get_stats(struct net_device *net) | |
2590 | { | |
2591 | return &((struct gsm_mux_net *)netdev_priv(net))->stats; | |
2592 | } | |
2593 | static void dlci_net_free(struct gsm_dlci *dlci) | |
2594 | { | |
2595 | if (!dlci->net) { | |
2596 | WARN_ON(1); | |
2597 | return; | |
2598 | } | |
2599 | dlci->adaption = dlci->prev_adaption; | |
2600 | dlci->data = dlci->prev_data; | |
2601 | free_netdev(dlci->net); | |
2602 | dlci->net = NULL; | |
2603 | } | |
2604 | static void net_free(struct kref *ref) | |
2605 | { | |
2606 | struct gsm_mux_net *mux_net; | |
2607 | struct gsm_dlci *dlci; | |
2608 | ||
2609 | mux_net = container_of(ref, struct gsm_mux_net, ref); | |
2610 | dlci = mux_net->dlci; | |
2611 | ||
2612 | if (dlci->net) { | |
2613 | unregister_netdev(dlci->net); | |
2614 | dlci_net_free(dlci); | |
2615 | } | |
2616 | } | |
2617 | ||
6ab8fba7 RG |
2618 | static inline void muxnet_get(struct gsm_mux_net *mux_net) |
2619 | { | |
2620 | kref_get(&mux_net->ref); | |
2621 | } | |
2622 | ||
2623 | static inline void muxnet_put(struct gsm_mux_net *mux_net) | |
2624 | { | |
2625 | kref_put(&mux_net->ref, net_free); | |
2626 | } | |
2627 | ||
bcd5abe2 RG |
2628 | static int gsm_mux_net_start_xmit(struct sk_buff *skb, |
2629 | struct net_device *net) | |
2630 | { | |
2631 | struct gsm_mux_net *mux_net = (struct gsm_mux_net *)netdev_priv(net); | |
2632 | struct gsm_dlci *dlci = mux_net->dlci; | |
6ab8fba7 | 2633 | muxnet_get(mux_net); |
bcd5abe2 RG |
2634 | |
2635 | skb_queue_head(&dlci->skb_list, skb); | |
2636 | STATS(net).tx_packets++; | |
2637 | STATS(net).tx_bytes += skb->len; | |
2638 | gsm_dlci_data_kick(dlci); | |
2639 | /* And tell the kernel when the last transmit started. */ | |
2640 | net->trans_start = jiffies; | |
6ab8fba7 | 2641 | muxnet_put(mux_net); |
bcd5abe2 RG |
2642 | return NETDEV_TX_OK; |
2643 | } | |
2644 | ||
2645 | /* called when a packet did not ack after watchdogtimeout */ | |
2646 | static void gsm_mux_net_tx_timeout(struct net_device *net) | |
2647 | { | |
2648 | /* Tell syslog we are hosed. */ | |
2649 | dev_dbg(&net->dev, "Tx timed out.\n"); | |
2650 | ||
2651 | /* Update statistics */ | |
2652 | STATS(net).tx_errors++; | |
2653 | } | |
2654 | ||
2655 | static void gsm_mux_rx_netchar(struct gsm_dlci *dlci, | |
2656 | unsigned char *in_buf, int size) | |
2657 | { | |
2658 | struct net_device *net = dlci->net; | |
2659 | struct sk_buff *skb; | |
2660 | struct gsm_mux_net *mux_net = (struct gsm_mux_net *)netdev_priv(net); | |
6ab8fba7 | 2661 | muxnet_get(mux_net); |
bcd5abe2 RG |
2662 | |
2663 | /* Allocate an sk_buff */ | |
2664 | skb = dev_alloc_skb(size + NET_IP_ALIGN); | |
2665 | if (!skb) { | |
2666 | /* We got no receive buffer. */ | |
2667 | STATS(net).rx_dropped++; | |
6ab8fba7 | 2668 | muxnet_put(mux_net); |
bcd5abe2 RG |
2669 | return; |
2670 | } | |
2671 | skb_reserve(skb, NET_IP_ALIGN); | |
2672 | memcpy(skb_put(skb, size), in_buf, size); | |
2673 | ||
2674 | skb->dev = net; | |
2675 | skb->protocol = __constant_htons(ETH_P_IP); | |
2676 | ||
2677 | /* Ship it off to the kernel */ | |
2678 | netif_rx(skb); | |
2679 | ||
2680 | /* update out statistics */ | |
2681 | STATS(net).rx_packets++; | |
2682 | STATS(net).rx_bytes += size; | |
6ab8fba7 | 2683 | muxnet_put(mux_net); |
bcd5abe2 RG |
2684 | return; |
2685 | } | |
2686 | ||
2687 | int gsm_change_mtu(struct net_device *net, int new_mtu) | |
2688 | { | |
2689 | struct gsm_mux_net *mux_net = (struct gsm_mux_net *)netdev_priv(net); | |
2690 | if ((new_mtu < 8) || (new_mtu > mux_net->dlci->gsm->mtu)) | |
2691 | return -EINVAL; | |
2692 | net->mtu = new_mtu; | |
2693 | return 0; | |
2694 | } | |
2695 | ||
2696 | static void gsm_mux_net_init(struct net_device *net) | |
2697 | { | |
2698 | static const struct net_device_ops gsm_netdev_ops = { | |
2699 | .ndo_open = gsm_mux_net_open, | |
2700 | .ndo_stop = gsm_mux_net_close, | |
2701 | .ndo_start_xmit = gsm_mux_net_start_xmit, | |
2702 | .ndo_tx_timeout = gsm_mux_net_tx_timeout, | |
2703 | .ndo_get_stats = gsm_mux_net_get_stats, | |
2704 | .ndo_change_mtu = gsm_change_mtu, | |
2705 | }; | |
2706 | ||
2707 | net->netdev_ops = &gsm_netdev_ops; | |
2708 | ||
2709 | /* fill in the other fields */ | |
2710 | net->watchdog_timeo = GSM_NET_TX_TIMEOUT; | |
2711 | net->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; | |
2712 | net->type = ARPHRD_NONE; | |
2713 | net->tx_queue_len = 10; | |
2714 | } | |
2715 | ||
2716 | ||
2717 | /* caller holds the dlci mutex */ | |
2718 | static void gsm_destroy_network(struct gsm_dlci *dlci) | |
2719 | { | |
2720 | struct gsm_mux_net *mux_net; | |
2721 | ||
2722 | pr_debug("destroy network interface"); | |
2723 | if (!dlci->net) | |
2724 | return; | |
2725 | mux_net = (struct gsm_mux_net *)netdev_priv(dlci->net); | |
6ab8fba7 | 2726 | muxnet_put(mux_net); |
bcd5abe2 RG |
2727 | } |
2728 | ||
2729 | ||
2730 | /* caller holds the dlci mutex */ | |
2731 | static int gsm_create_network(struct gsm_dlci *dlci, struct gsm_netconfig *nc) | |
2732 | { | |
2733 | char *netname; | |
2734 | int retval = 0; | |
2735 | struct net_device *net; | |
2736 | struct gsm_mux_net *mux_net; | |
2737 | ||
2738 | if (!capable(CAP_NET_ADMIN)) | |
2739 | return -EPERM; | |
2740 | ||
2741 | /* Already in a non tty mode */ | |
2742 | if (dlci->adaption > 2) | |
2743 | return -EBUSY; | |
2744 | ||
2745 | if (nc->protocol != htons(ETH_P_IP)) | |
2746 | return -EPROTONOSUPPORT; | |
2747 | ||
2748 | if (nc->adaption != 3 && nc->adaption != 4) | |
2749 | return -EPROTONOSUPPORT; | |
2750 | ||
2751 | pr_debug("create network interface"); | |
2752 | ||
2753 | netname = "gsm%d"; | |
2754 | if (nc->if_name[0] != '\0') | |
2755 | netname = nc->if_name; | |
2756 | net = alloc_netdev(sizeof(struct gsm_mux_net), | |
2757 | netname, | |
2758 | gsm_mux_net_init); | |
2759 | if (!net) { | |
2760 | pr_err("alloc_netdev failed"); | |
2761 | return -ENOMEM; | |
2762 | } | |
2763 | net->mtu = dlci->gsm->mtu; | |
2764 | mux_net = (struct gsm_mux_net *)netdev_priv(net); | |
2765 | mux_net->dlci = dlci; | |
2766 | kref_init(&mux_net->ref); | |
2767 | strncpy(nc->if_name, net->name, IFNAMSIZ); /* return net name */ | |
2768 | ||
2769 | /* reconfigure dlci for network */ | |
2770 | dlci->prev_adaption = dlci->adaption; | |
2771 | dlci->prev_data = dlci->data; | |
2772 | dlci->adaption = nc->adaption; | |
2773 | dlci->data = gsm_mux_rx_netchar; | |
2774 | dlci->net = net; | |
2775 | ||
2776 | pr_debug("register netdev"); | |
2777 | retval = register_netdev(net); | |
2778 | if (retval) { | |
2779 | pr_err("network register fail %d\n", retval); | |
2780 | dlci_net_free(dlci); | |
2781 | return retval; | |
2782 | } | |
2783 | return net->ifindex; /* return network index */ | |
2784 | } | |
e1eaea46 AC |
2785 | |
2786 | /* Line discipline for real tty */ | |
2787 | struct tty_ldisc_ops tty_ldisc_packet = { | |
2788 | .owner = THIS_MODULE, | |
2789 | .magic = TTY_LDISC_MAGIC, | |
2790 | .name = "n_gsm", | |
2791 | .open = gsmld_open, | |
2792 | .close = gsmld_close, | |
2793 | .flush_buffer = gsmld_flush_buffer, | |
2794 | .chars_in_buffer = gsmld_chars_in_buffer, | |
2795 | .read = gsmld_read, | |
2796 | .write = gsmld_write, | |
2797 | .ioctl = gsmld_ioctl, | |
2798 | .poll = gsmld_poll, | |
2799 | .receive_buf = gsmld_receive_buf, | |
2800 | .write_wakeup = gsmld_write_wakeup | |
2801 | }; | |
2802 | ||
2803 | /* | |
2804 | * Virtual tty side | |
2805 | */ | |
2806 | ||
2807 | #define TX_SIZE 512 | |
2808 | ||
2809 | static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk) | |
2810 | { | |
2811 | u8 modembits[5]; | |
2812 | struct gsm_control *ctrl; | |
2813 | int len = 2; | |
2814 | ||
2815 | if (brk) | |
2816 | len++; | |
2817 | ||
2818 | modembits[0] = len << 1 | EA; /* Data bytes */ | |
2819 | modembits[1] = dlci->addr << 2 | 3; /* DLCI, EA, 1 */ | |
2820 | modembits[2] = gsm_encode_modem(dlci) << 1 | EA; | |
2821 | if (brk) | |
2822 | modembits[3] = brk << 4 | 2 | EA; /* Valid, EA */ | |
2823 | ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len + 1); | |
2824 | if (ctrl == NULL) | |
2825 | return -ENOMEM; | |
2826 | return gsm_control_wait(dlci->gsm, ctrl); | |
2827 | } | |
2828 | ||
2829 | static int gsm_carrier_raised(struct tty_port *port) | |
2830 | { | |
2831 | struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); | |
2832 | /* Not yet open so no carrier info */ | |
2833 | if (dlci->state != DLCI_OPEN) | |
2834 | return 0; | |
2835 | if (debug & 2) | |
2836 | return 1; | |
2837 | return dlci->modem_rx & TIOCM_CD; | |
2838 | } | |
2839 | ||
2840 | static void gsm_dtr_rts(struct tty_port *port, int onoff) | |
2841 | { | |
2842 | struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); | |
2843 | unsigned int modem_tx = dlci->modem_tx; | |
2844 | if (onoff) | |
2845 | modem_tx |= TIOCM_DTR | TIOCM_RTS; | |
2846 | else | |
2847 | modem_tx &= ~(TIOCM_DTR | TIOCM_RTS); | |
2848 | if (modem_tx != dlci->modem_tx) { | |
2849 | dlci->modem_tx = modem_tx; | |
2850 | gsmtty_modem_update(dlci, 0); | |
2851 | } | |
2852 | } | |
2853 | ||
2854 | static const struct tty_port_operations gsm_port_ops = { | |
2855 | .carrier_raised = gsm_carrier_raised, | |
2856 | .dtr_rts = gsm_dtr_rts, | |
2857 | }; | |
2858 | ||
2859 | ||
2860 | static int gsmtty_open(struct tty_struct *tty, struct file *filp) | |
2861 | { | |
2862 | struct gsm_mux *gsm; | |
2863 | struct gsm_dlci *dlci; | |
2864 | struct tty_port *port; | |
2865 | unsigned int line = tty->index; | |
2866 | unsigned int mux = line >> 6; | |
2867 | ||
2868 | line = line & 0x3F; | |
2869 | ||
2870 | if (mux >= MAX_MUX) | |
2871 | return -ENXIO; | |
2872 | /* FIXME: we need to lock gsm_mux for lifetimes of ttys eventually */ | |
2873 | if (gsm_mux[mux] == NULL) | |
2874 | return -EUNATCH; | |
2875 | if (line == 0 || line > 61) /* 62/63 reserved */ | |
2876 | return -ECHRNG; | |
2877 | gsm = gsm_mux[mux]; | |
2878 | if (gsm->dead) | |
2879 | return -EL2HLT; | |
2880 | dlci = gsm->dlci[line]; | |
2881 | if (dlci == NULL) | |
2882 | dlci = gsm_dlci_alloc(gsm, line); | |
2883 | if (dlci == NULL) | |
2884 | return -ENOMEM; | |
2885 | port = &dlci->port; | |
2886 | port->count++; | |
2887 | tty->driver_data = dlci; | |
6ab8fba7 RG |
2888 | dlci_get(dlci); |
2889 | dlci_get(dlci->gsm->dlci[0]); | |
2890 | mux_get(dlci->gsm); | |
e1eaea46 AC |
2891 | tty_port_tty_set(port, tty); |
2892 | ||
2893 | dlci->modem_rx = 0; | |
2894 | /* We could in theory open and close before we wait - eg if we get | |
2895 | a DM straight back. This is ok as that will have caused a hangup */ | |
2896 | set_bit(ASYNCB_INITIALIZED, &port->flags); | |
2897 | /* Start sending off SABM messages */ | |
2898 | gsm_dlci_begin_open(dlci); | |
2899 | /* And wait for virtual carrier */ | |
2900 | return tty_port_block_til_ready(port, tty, filp); | |
2901 | } | |
2902 | ||
2903 | static void gsmtty_close(struct tty_struct *tty, struct file *filp) | |
2904 | { | |
2905 | struct gsm_dlci *dlci = tty->driver_data; | |
6ab8fba7 RG |
2906 | struct gsm_mux *gsm; |
2907 | ||
e1eaea46 AC |
2908 | if (dlci == NULL) |
2909 | return; | |
bcd5abe2 RG |
2910 | mutex_lock(&dlci->mutex); |
2911 | gsm_destroy_network(dlci); | |
2912 | mutex_unlock(&dlci->mutex); | |
6ab8fba7 | 2913 | gsm = dlci->gsm; |
e1eaea46 | 2914 | if (tty_port_close_start(&dlci->port, tty, filp) == 0) |
6ab8fba7 | 2915 | goto out; |
e1eaea46 AC |
2916 | gsm_dlci_begin_close(dlci); |
2917 | tty_port_close_end(&dlci->port, tty); | |
2918 | tty_port_tty_set(&dlci->port, NULL); | |
6ab8fba7 RG |
2919 | out: |
2920 | dlci_put(dlci); | |
2921 | dlci_put(gsm->dlci[0]); | |
2922 | mux_put(gsm); | |
e1eaea46 AC |
2923 | } |
2924 | ||
2925 | static void gsmtty_hangup(struct tty_struct *tty) | |
2926 | { | |
2927 | struct gsm_dlci *dlci = tty->driver_data; | |
2928 | tty_port_hangup(&dlci->port); | |
2929 | gsm_dlci_begin_close(dlci); | |
2930 | } | |
2931 | ||
2932 | static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf, | |
2933 | int len) | |
2934 | { | |
2935 | struct gsm_dlci *dlci = tty->driver_data; | |
2936 | /* Stuff the bytes into the fifo queue */ | |
2937 | int sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock); | |
2938 | /* Need to kick the channel */ | |
2939 | gsm_dlci_data_kick(dlci); | |
2940 | return sent; | |
2941 | } | |
2942 | ||
2943 | static int gsmtty_write_room(struct tty_struct *tty) | |
2944 | { | |
2945 | struct gsm_dlci *dlci = tty->driver_data; | |
2946 | return TX_SIZE - kfifo_len(dlci->fifo); | |
2947 | } | |
2948 | ||
2949 | static int gsmtty_chars_in_buffer(struct tty_struct *tty) | |
2950 | { | |
2951 | struct gsm_dlci *dlci = tty->driver_data; | |
2952 | return kfifo_len(dlci->fifo); | |
2953 | } | |
2954 | ||
2955 | static void gsmtty_flush_buffer(struct tty_struct *tty) | |
2956 | { | |
2957 | struct gsm_dlci *dlci = tty->driver_data; | |
2958 | /* Caution needed: If we implement reliable transport classes | |
2959 | then the data being transmitted can't simply be junked once | |
2960 | it has first hit the stack. Until then we can just blow it | |
2961 | away */ | |
2962 | kfifo_reset(dlci->fifo); | |
2963 | /* Need to unhook this DLCI from the transmit queue logic */ | |
2964 | } | |
2965 | ||
2966 | static void gsmtty_wait_until_sent(struct tty_struct *tty, int timeout) | |
2967 | { | |
2968 | /* The FIFO handles the queue so the kernel will do the right | |
2969 | thing waiting on chars_in_buffer before calling us. No work | |
2970 | to do here */ | |
2971 | } | |
2972 | ||
60b33c13 | 2973 | static int gsmtty_tiocmget(struct tty_struct *tty) |
e1eaea46 AC |
2974 | { |
2975 | struct gsm_dlci *dlci = tty->driver_data; | |
2976 | return dlci->modem_rx; | |
2977 | } | |
2978 | ||
20b9d177 | 2979 | static int gsmtty_tiocmset(struct tty_struct *tty, |
e1eaea46 AC |
2980 | unsigned int set, unsigned int clear) |
2981 | { | |
2982 | struct gsm_dlci *dlci = tty->driver_data; | |
2983 | unsigned int modem_tx = dlci->modem_tx; | |
2984 | ||
2985 | modem_tx &= clear; | |
2986 | modem_tx |= set; | |
2987 | ||
2988 | if (modem_tx != dlci->modem_tx) { | |
2989 | dlci->modem_tx = modem_tx; | |
2990 | return gsmtty_modem_update(dlci, 0); | |
2991 | } | |
2992 | return 0; | |
2993 | } | |
2994 | ||
2995 | ||
6caa76b7 | 2996 | static int gsmtty_ioctl(struct tty_struct *tty, |
e1eaea46 AC |
2997 | unsigned int cmd, unsigned long arg) |
2998 | { | |
bcd5abe2 RG |
2999 | struct gsm_dlci *dlci = tty->driver_data; |
3000 | struct gsm_netconfig nc; | |
3001 | int index; | |
3002 | ||
3003 | switch (cmd) { | |
3004 | case GSMIOC_ENABLE_NET: | |
3005 | if (copy_from_user(&nc, (void __user *)arg, sizeof(nc))) | |
3006 | return -EFAULT; | |
3007 | nc.if_name[IFNAMSIZ-1] = '\0'; | |
3008 | /* return net interface index or error code */ | |
3009 | mutex_lock(&dlci->mutex); | |
3010 | index = gsm_create_network(dlci, &nc); | |
3011 | mutex_unlock(&dlci->mutex); | |
3012 | if (copy_to_user((void __user *)arg, &nc, sizeof(nc))) | |
3013 | return -EFAULT; | |
3014 | return index; | |
3015 | case GSMIOC_DISABLE_NET: | |
3016 | if (!capable(CAP_NET_ADMIN)) | |
3017 | return -EPERM; | |
3018 | mutex_lock(&dlci->mutex); | |
3019 | gsm_destroy_network(dlci); | |
3020 | mutex_unlock(&dlci->mutex); | |
3021 | return 0; | |
3022 | default: | |
3023 | return -ENOIOCTLCMD; | |
3024 | } | |
e1eaea46 AC |
3025 | } |
3026 | ||
3027 | static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old) | |
3028 | { | |
3029 | /* For the moment its fixed. In actual fact the speed information | |
3030 | for the virtual channel can be propogated in both directions by | |
3031 | the RPN control message. This however rapidly gets nasty as we | |
3032 | then have to remap modem signals each way according to whether | |
3033 | our virtual cable is null modem etc .. */ | |
3034 | tty_termios_copy_hw(tty->termios, old); | |
3035 | } | |
3036 | ||
3037 | static void gsmtty_throttle(struct tty_struct *tty) | |
3038 | { | |
3039 | struct gsm_dlci *dlci = tty->driver_data; | |
3040 | if (tty->termios->c_cflag & CRTSCTS) | |
3041 | dlci->modem_tx &= ~TIOCM_DTR; | |
3042 | dlci->throttled = 1; | |
3043 | /* Send an MSC with DTR cleared */ | |
3044 | gsmtty_modem_update(dlci, 0); | |
3045 | } | |
3046 | ||
3047 | static void gsmtty_unthrottle(struct tty_struct *tty) | |
3048 | { | |
3049 | struct gsm_dlci *dlci = tty->driver_data; | |
3050 | if (tty->termios->c_cflag & CRTSCTS) | |
3051 | dlci->modem_tx |= TIOCM_DTR; | |
3052 | dlci->throttled = 0; | |
3053 | /* Send an MSC with DTR set */ | |
3054 | gsmtty_modem_update(dlci, 0); | |
3055 | } | |
3056 | ||
3057 | static int gsmtty_break_ctl(struct tty_struct *tty, int state) | |
3058 | { | |
3059 | struct gsm_dlci *dlci = tty->driver_data; | |
3060 | int encode = 0; /* Off */ | |
3061 | ||
3062 | if (state == -1) /* "On indefinitely" - we can't encode this | |
3063 | properly */ | |
3064 | encode = 0x0F; | |
3065 | else if (state > 0) { | |
3066 | encode = state / 200; /* mS to encoding */ | |
3067 | if (encode > 0x0F) | |
3068 | encode = 0x0F; /* Best effort */ | |
3069 | } | |
3070 | return gsmtty_modem_update(dlci, encode); | |
3071 | } | |
3072 | ||
e1eaea46 AC |
3073 | |
3074 | /* Virtual ttys for the demux */ | |
3075 | static const struct tty_operations gsmtty_ops = { | |
3076 | .open = gsmtty_open, | |
3077 | .close = gsmtty_close, | |
3078 | .write = gsmtty_write, | |
3079 | .write_room = gsmtty_write_room, | |
3080 | .chars_in_buffer = gsmtty_chars_in_buffer, | |
3081 | .flush_buffer = gsmtty_flush_buffer, | |
3082 | .ioctl = gsmtty_ioctl, | |
3083 | .throttle = gsmtty_throttle, | |
3084 | .unthrottle = gsmtty_unthrottle, | |
3085 | .set_termios = gsmtty_set_termios, | |
3086 | .hangup = gsmtty_hangup, | |
3087 | .wait_until_sent = gsmtty_wait_until_sent, | |
3088 | .tiocmget = gsmtty_tiocmget, | |
3089 | .tiocmset = gsmtty_tiocmset, | |
3090 | .break_ctl = gsmtty_break_ctl, | |
3091 | }; | |
3092 | ||
3093 | ||
3094 | ||
3095 | static int __init gsm_init(void) | |
3096 | { | |
3097 | /* Fill in our line protocol discipline, and register it */ | |
3098 | int status = tty_register_ldisc(N_GSM0710, &tty_ldisc_packet); | |
3099 | if (status != 0) { | |
5f9a31d6 AC |
3100 | pr_err("n_gsm: can't register line discipline (err = %d)\n", |
3101 | status); | |
e1eaea46 AC |
3102 | return status; |
3103 | } | |
3104 | ||
3105 | gsm_tty_driver = alloc_tty_driver(256); | |
3106 | if (!gsm_tty_driver) { | |
3107 | tty_unregister_ldisc(N_GSM0710); | |
5f9a31d6 | 3108 | pr_err("gsm_init: tty allocation failed.\n"); |
e1eaea46 AC |
3109 | return -EINVAL; |
3110 | } | |
3111 | gsm_tty_driver->owner = THIS_MODULE; | |
3112 | gsm_tty_driver->driver_name = "gsmtty"; | |
3113 | gsm_tty_driver->name = "gsmtty"; | |
3114 | gsm_tty_driver->major = 0; /* Dynamic */ | |
3115 | gsm_tty_driver->minor_start = 0; | |
3116 | gsm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL; | |
3117 | gsm_tty_driver->subtype = SERIAL_TYPE_NORMAL; | |
3118 | gsm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV | |
5f9a31d6 | 3119 | | TTY_DRIVER_HARDWARE_BREAK; |
e1eaea46 AC |
3120 | gsm_tty_driver->init_termios = tty_std_termios; |
3121 | /* Fixme */ | |
3122 | gsm_tty_driver->init_termios.c_lflag &= ~ECHO; | |
3123 | tty_set_operations(gsm_tty_driver, &gsmtty_ops); | |
3124 | ||
3125 | spin_lock_init(&gsm_mux_lock); | |
3126 | ||
3127 | if (tty_register_driver(gsm_tty_driver)) { | |
3128 | put_tty_driver(gsm_tty_driver); | |
3129 | tty_unregister_ldisc(N_GSM0710); | |
5f9a31d6 | 3130 | pr_err("gsm_init: tty registration failed.\n"); |
e1eaea46 AC |
3131 | return -EBUSY; |
3132 | } | |
5f9a31d6 AC |
3133 | pr_debug("gsm_init: loaded as %d,%d.\n", |
3134 | gsm_tty_driver->major, gsm_tty_driver->minor_start); | |
e1eaea46 AC |
3135 | return 0; |
3136 | } | |
3137 | ||
3138 | static void __exit gsm_exit(void) | |
3139 | { | |
3140 | int status = tty_unregister_ldisc(N_GSM0710); | |
3141 | if (status != 0) | |
5f9a31d6 AC |
3142 | pr_err("n_gsm: can't unregister line discipline (err = %d)\n", |
3143 | status); | |
e1eaea46 AC |
3144 | tty_unregister_driver(gsm_tty_driver); |
3145 | put_tty_driver(gsm_tty_driver); | |
e1eaea46 AC |
3146 | } |
3147 | ||
3148 | module_init(gsm_init); | |
3149 | module_exit(gsm_exit); | |
3150 | ||
3151 | ||
3152 | MODULE_LICENSE("GPL"); | |
3153 | MODULE_ALIAS_LDISC(N_GSM0710); |