diff options
author | Alan Cox <alan@linux.intel.com> | 2010-03-26 07:32:54 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-05-21 12:34:29 -0400 |
commit | e1eaea46bb4020b38a141b84f88565d4603f8dd0 (patch) | |
tree | ade3efe84cf4aff3cb29ec2ea2be30c97b141ad7 | |
parent | 1ff454ef9b1e852e8f4d295a68a715b1dddf233c (diff) |
tty: n_gsm line discipline
Add an implementation of GSM 0710 MUX. The implementation currently supports
- Basic and advanced framing (as either end of the link)
- UI or UIH data frames
- Adaption layer 1-4 (1 and 2 via tty, 3 and 4 as skbuff lists)
- Modem and control messages including the correct retry process
- Flow control
and exposes the MUX channels as a set of virtual tty devices including modem
signals. This is an experimental driver.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/char/Kconfig | 9 | ||||
-rw-r--r-- | drivers/char/Makefile | 1 | ||||
-rw-r--r-- | drivers/char/n_gsm.c | 2763 | ||||
-rw-r--r-- | include/linux/gsmmux.h | 25 | ||||
-rw-r--r-- | include/linux/tty.h | 1 |
5 files changed, 2798 insertions, 1 deletions
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index 3141dd3b6e53..51a57009aec8 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig | |||
@@ -276,11 +276,18 @@ config N_HDLC | |||
276 | Allows synchronous HDLC communications with tty device drivers that | 276 | Allows synchronous HDLC communications with tty device drivers that |
277 | support synchronous HDLC such as the Microgate SyncLink adapter. | 277 | support synchronous HDLC such as the Microgate SyncLink adapter. |
278 | 278 | ||
279 | This driver can only be built as a module ( = code which can be | 279 | This driver can be built as a module ( = code which can be |
280 | inserted in and removed from the running kernel whenever you want). | 280 | inserted in and removed from the running kernel whenever you want). |
281 | The module will be called n_hdlc. If you want to do that, say M | 281 | The module will be called n_hdlc. If you want to do that, say M |
282 | here. | 282 | here. |
283 | 283 | ||
284 | config N_GSM | ||
285 | tristate "GSM MUX line discipline support (EXPERIMENTAL)" | ||
286 | depends on EXPERIMENTAL | ||
287 | help | ||
288 | This line discipline provides support for the GSM MUX protocol and | ||
289 | presents the mux as a set of 61 individual tty devices. | ||
290 | |||
284 | config RISCOM8 | 291 | config RISCOM8 |
285 | tristate "SDL RISCom/8 card support" | 292 | tristate "SDL RISCom/8 card support" |
286 | depends on SERIAL_NONSTANDARD | 293 | depends on SERIAL_NONSTANDARD |
diff --git a/drivers/char/Makefile b/drivers/char/Makefile index f957edf7e45d..d39be4cf1f5d 100644 --- a/drivers/char/Makefile +++ b/drivers/char/Makefile | |||
@@ -40,6 +40,7 @@ obj-$(CONFIG_SYNCLINK) += synclink.o | |||
40 | obj-$(CONFIG_SYNCLINKMP) += synclinkmp.o | 40 | obj-$(CONFIG_SYNCLINKMP) += synclinkmp.o |
41 | obj-$(CONFIG_SYNCLINK_GT) += synclink_gt.o | 41 | obj-$(CONFIG_SYNCLINK_GT) += synclink_gt.o |
42 | obj-$(CONFIG_N_HDLC) += n_hdlc.o | 42 | obj-$(CONFIG_N_HDLC) += n_hdlc.o |
43 | obj-$(CONFIG_N_GSM) += n_gsm.o | ||
43 | obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o | 44 | obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o |
44 | obj-$(CONFIG_SX) += sx.o generic_serial.o | 45 | obj-$(CONFIG_SX) += sx.o generic_serial.o |
45 | obj-$(CONFIG_RIO) += rio/ generic_serial.o | 46 | obj-$(CONFIG_RIO) += rio/ generic_serial.o |
diff --git a/drivers/char/n_gsm.c b/drivers/char/n_gsm.c new file mode 100644 index 000000000000..c4161d5e053d --- /dev/null +++ b/drivers/char/n_gsm.c | |||
@@ -0,0 +1,2763 @@ | |||
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 | ||
22 | * Partly done: hooks so you can pull off frames to non tty devs | ||
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> | ||
46 | #include <linux/timer.h> | ||
47 | #include <linux/ctype.h> | ||
48 | #include <linux/mm.h> | ||
49 | #include <linux/string.h> | ||
50 | #include <linux/slab.h> | ||
51 | #include <linux/poll.h> | ||
52 | #include <linux/bitops.h> | ||
53 | #include <linux/file.h> | ||
54 | #include <linux/uaccess.h> | ||
55 | #include <linux/module.h> | ||
56 | #include <linux/timer.h> | ||
57 | #include <linux/tty_flip.h> | ||
58 | #include <linux/tty_driver.h> | ||
59 | #include <linux/serial.h> | ||
60 | #include <linux/kfifo.h> | ||
61 | #include <linux/skbuff.h> | ||
62 | #include <linux/gsmmux.h> | ||
63 | |||
64 | static int debug; | ||
65 | module_param(debug, int, 0600); | ||
66 | |||
67 | #define T1 (HZ/10) | ||
68 | #define T2 (HZ/3) | ||
69 | #define N2 3 | ||
70 | |||
71 | /* Use long timers for testing at low speed with debug on */ | ||
72 | #ifdef DEBUG_TIMING | ||
73 | #define T1 HZ | ||
74 | #define T2 (2 * HZ) | ||
75 | #endif | ||
76 | |||
77 | /* Semi-arbitary buffer size limits. 0710 is normally run with 32-64 byte | ||
78 | limits so this is plenty */ | ||
79 | #define MAX_MRU 512 | ||
80 | #define MAX_MTU 512 | ||
81 | |||
82 | /* | ||
83 | * Each block of data we have queued to go out is in the form of | ||
84 | * a gsm_msg which holds everything we need in a link layer independant | ||
85 | * format | ||
86 | */ | ||
87 | |||
88 | struct gsm_msg { | ||
89 | struct gsm_msg *next; | ||
90 | u8 addr; /* DLCI address + flags */ | ||
91 | u8 ctrl; /* Control byte + flags */ | ||
92 | unsigned int len; /* Length of data block (can be zero) */ | ||
93 | unsigned char *data; /* Points into buffer but not at the start */ | ||
94 | unsigned char buffer[0]; | ||
95 | }; | ||
96 | |||
97 | /* | ||
98 | * Each active data link has a gsm_dlci structure associated which ties | ||
99 | * the link layer to an optional tty (if the tty side is open). To avoid | ||
100 | * complexity right now these are only ever freed up when the mux is | ||
101 | * shut down. | ||
102 | * | ||
103 | * At the moment we don't free DLCI objects until the mux is torn down | ||
104 | * this avoid object life time issues but might be worth review later. | ||
105 | */ | ||
106 | |||
107 | struct gsm_dlci { | ||
108 | struct gsm_mux *gsm; | ||
109 | int addr; | ||
110 | int state; | ||
111 | #define DLCI_CLOSED 0 | ||
112 | #define DLCI_OPENING 1 /* Sending SABM not seen UA */ | ||
113 | #define DLCI_OPEN 2 /* SABM/UA complete */ | ||
114 | #define DLCI_CLOSING 3 /* Sending DISC not seen UA/DM */ | ||
115 | |||
116 | /* Link layer */ | ||
117 | spinlock_t lock; /* Protects the internal state */ | ||
118 | struct timer_list t1; /* Retransmit timer for SABM and UA */ | ||
119 | int retries; | ||
120 | /* Uplink tty if active */ | ||
121 | struct tty_port port; /* The tty bound to this DLCI if there is one */ | ||
122 | struct kfifo *fifo; /* Queue fifo for the DLCI */ | ||
123 | struct kfifo _fifo; /* For new fifo API porting only */ | ||
124 | int adaption; /* Adaption layer in use */ | ||
125 | u32 modem_rx; /* Our incoming virtual modem lines */ | ||
126 | u32 modem_tx; /* Our outgoing modem lines */ | ||
127 | int dead; /* Refuse re-open */ | ||
128 | /* Flow control */ | ||
129 | int throttled; /* Private copy of throttle state */ | ||
130 | int constipated; /* Throttle status for outgoing */ | ||
131 | /* Packetised I/O */ | ||
132 | struct sk_buff *skb; /* Frame being sent */ | ||
133 | struct sk_buff_head skb_list; /* Queued frames */ | ||
134 | /* Data handling callback */ | ||
135 | void (*data)(struct gsm_dlci *dlci, u8 *data, int len); | ||
136 | }; | ||
137 | |||
138 | /* DLCI 0, 62/63 are special or reseved see gsmtty_open */ | ||
139 | |||
140 | #define NUM_DLCI 64 | ||
141 | |||
142 | /* | ||
143 | * DLCI 0 is used to pass control blocks out of band of the data | ||
144 | * flow (and with a higher link priority). One command can be outstanding | ||
145 | * at a time and we use this structure to manage them. They are created | ||
146 | * and destroyed by the user context, and updated by the receive paths | ||
147 | * and timers | ||
148 | */ | ||
149 | |||
150 | struct gsm_control { | ||
151 | u8 cmd; /* Command we are issuing */ | ||
152 | u8 *data; /* Data for the command in case we retransmit */ | ||
153 | int len; /* Length of block for retransmission */ | ||
154 | int done; /* Done flag */ | ||
155 | int error; /* Error if any */ | ||
156 | }; | ||
157 | |||
158 | /* | ||
159 | * Each GSM mux we have is represented by this structure. If we are | ||
160 | * operating as an ldisc then we use this structure as our ldisc | ||
161 | * state. We need to sort out lifetimes and locking with respect | ||
162 | * to the gsm mux array. For now we don't free DLCI objects that | ||
163 | * have been instantiated until the mux itself is terminated. | ||
164 | * | ||
165 | * To consider further: tty open versus mux shutdown. | ||
166 | */ | ||
167 | |||
168 | struct gsm_mux { | ||
169 | struct tty_struct *tty; /* The tty our ldisc is bound to */ | ||
170 | spinlock_t lock; | ||
171 | |||
172 | /* Events on the GSM channel */ | ||
173 | wait_queue_head_t event; | ||
174 | |||
175 | /* Bits for GSM mode decoding */ | ||
176 | |||
177 | /* Framing Layer */ | ||
178 | unsigned char *buf; | ||
179 | int state; | ||
180 | #define GSM_SEARCH 0 | ||
181 | #define GSM_START 1 | ||
182 | #define GSM_ADDRESS 2 | ||
183 | #define GSM_CONTROL 3 | ||
184 | #define GSM_LEN 4 | ||
185 | #define GSM_DATA 5 | ||
186 | #define GSM_FCS 6 | ||
187 | #define GSM_OVERRUN 7 | ||
188 | unsigned int len; | ||
189 | unsigned int address; | ||
190 | unsigned int count; | ||
191 | int escape; | ||
192 | int encoding; | ||
193 | u8 control; | ||
194 | u8 fcs; | ||
195 | u8 *txframe; /* TX framing buffer */ | ||
196 | |||
197 | /* Methods for the receiver side */ | ||
198 | void (*receive)(struct gsm_mux *gsm, u8 ch); | ||
199 | void (*error)(struct gsm_mux *gsm, u8 ch, u8 flag); | ||
200 | /* And transmit side */ | ||
201 | int (*output)(struct gsm_mux *mux, u8 *data, int len); | ||
202 | |||
203 | /* Link Layer */ | ||
204 | unsigned int mru; | ||
205 | unsigned int mtu; | ||
206 | int initiator; /* Did we initiate connection */ | ||
207 | int dead; /* Has the mux been shut down */ | ||
208 | struct gsm_dlci *dlci[NUM_DLCI]; | ||
209 | int constipated; /* Asked by remote to shut up */ | ||
210 | |||
211 | spinlock_t tx_lock; | ||
212 | unsigned int tx_bytes; /* TX data outstanding */ | ||
213 | #define TX_THRESH_HI 8192 | ||
214 | #define TX_THRESH_LO 2048 | ||
215 | struct gsm_msg *tx_head; /* Pending data packets */ | ||
216 | struct gsm_msg *tx_tail; | ||
217 | |||
218 | /* Control messages */ | ||
219 | struct timer_list t2_timer; /* Retransmit timer for commands */ | ||
220 | int cretries; /* Command retry counter */ | ||
221 | struct gsm_control *pending_cmd;/* Our current pending command */ | ||
222 | spinlock_t control_lock; /* Protects the pending command */ | ||
223 | |||
224 | /* Configuration */ | ||
225 | int adaption; /* 1 or 2 supported */ | ||
226 | u8 ftype; /* UI or UIH */ | ||
227 | int t1, t2; /* Timers in 1/100th of a sec */ | ||
228 | int n2; /* Retry count */ | ||
229 | |||
230 | /* Statistics (not currently exposed) */ | ||
231 | unsigned long bad_fcs; | ||
232 | unsigned long malformed; | ||
233 | unsigned long io_error; | ||
234 | unsigned long bad_size; | ||
235 | unsigned long unsupported; | ||
236 | }; | ||
237 | |||
238 | |||
239 | /* | ||
240 | * Mux objects - needed so that we can translate a tty index into the | ||
241 | * relevant mux and DLCI. | ||
242 | */ | ||
243 | |||
244 | #define MAX_MUX 4 /* 256 minors */ | ||
245 | static struct gsm_mux *gsm_mux[MAX_MUX]; /* GSM muxes */ | ||
246 | static spinlock_t gsm_mux_lock; | ||
247 | |||
248 | /* | ||
249 | * This section of the driver logic implements the GSM encodings | ||
250 | * both the basic and the 'advanced'. Reliable transport is not | ||
251 | * supported. | ||
252 | */ | ||
253 | |||
254 | #define CR 0x02 | ||
255 | #define EA 0x01 | ||
256 | #define PF 0x10 | ||
257 | |||
258 | /* I is special: the rest are ..*/ | ||
259 | #define RR 0x01 | ||
260 | #define UI 0x03 | ||
261 | #define RNR 0x05 | ||
262 | #define REJ 0x09 | ||
263 | #define DM 0x0F | ||
264 | #define SABM 0x2F | ||
265 | #define DISC 0x43 | ||
266 | #define UA 0x63 | ||
267 | #define UIH 0xEF | ||
268 | |||
269 | /* Channel commands */ | ||
270 | #define CMD_NSC 0x09 | ||
271 | #define CMD_TEST 0x11 | ||
272 | #define CMD_PSC 0x21 | ||
273 | #define CMD_RLS 0x29 | ||
274 | #define CMD_FCOFF 0x31 | ||
275 | #define CMD_PN 0x41 | ||
276 | #define CMD_RPN 0x49 | ||
277 | #define CMD_FCON 0x51 | ||
278 | #define CMD_CLD 0x61 | ||
279 | #define CMD_SNC 0x69 | ||
280 | #define CMD_MSC 0x71 | ||
281 | |||
282 | /* Virtual modem bits */ | ||
283 | #define MDM_FC 0x01 | ||
284 | #define MDM_RTC 0x02 | ||
285 | #define MDM_RTR 0x04 | ||
286 | #define MDM_IC 0x20 | ||
287 | #define MDM_DV 0x40 | ||
288 | |||
289 | #define GSM0_SOF 0xF9 | ||
290 | #define GSM1_SOF 0x7E | ||
291 | #define GSM1_ESCAPE 0x7D | ||
292 | #define GSM1_ESCAPE_BITS 0x20 | ||
293 | #define XON 0x11 | ||
294 | #define XOFF 0x13 | ||
295 | |||
296 | static const struct tty_port_operations gsm_port_ops; | ||
297 | |||
298 | /* | ||
299 | * CRC table for GSM 0710 | ||
300 | */ | ||
301 | |||
302 | static const u8 gsm_fcs8[256] = { | ||
303 | 0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75, | ||
304 | 0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B, | ||
305 | 0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69, | ||
306 | 0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67, | ||
307 | 0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D, | ||
308 | 0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43, | ||
309 | 0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51, | ||
310 | 0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F, | ||
311 | 0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05, | ||
312 | 0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B, | ||
313 | 0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19, | ||
314 | 0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17, | ||
315 | 0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D, | ||
316 | 0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33, | ||
317 | 0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21, | ||
318 | 0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F, | ||
319 | 0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95, | ||
320 | 0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B, | ||
321 | 0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89, | ||
322 | 0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87, | ||
323 | 0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD, | ||
324 | 0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3, | ||
325 | 0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1, | ||
326 | 0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF, | ||
327 | 0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5, | ||
328 | 0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB, | ||
329 | 0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9, | ||
330 | 0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7, | ||
331 | 0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD, | ||
332 | 0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3, | ||
333 | 0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1, | ||
334 | 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF | ||
335 | }; | ||
336 | |||
337 | #define INIT_FCS 0xFF | ||
338 | #define GOOD_FCS 0xCF | ||
339 | |||
340 | /** | ||
341 | * gsm_fcs_add - update FCS | ||
342 | * @fcs: Current FCS | ||
343 | * @c: Next data | ||
344 | * | ||
345 | * Update the FCS to include c. Uses the algorithm in the specification | ||
346 | * notes. | ||
347 | */ | ||
348 | |||
349 | static inline u8 gsm_fcs_add(u8 fcs, u8 c) | ||
350 | { | ||
351 | return gsm_fcs8[fcs ^ c]; | ||
352 | } | ||
353 | |||
354 | /** | ||
355 | * gsm_fcs_add_block - update FCS for a block | ||
356 | * @fcs: Current FCS | ||
357 | * @c: buffer of data | ||
358 | * @len: length of buffer | ||
359 | * | ||
360 | * Update the FCS to include c. Uses the algorithm in the specification | ||
361 | * notes. | ||
362 | */ | ||
363 | |||
364 | static inline u8 gsm_fcs_add_block(u8 fcs, u8 *c, int len) | ||
365 | { | ||
366 | while (len--) | ||
367 | fcs = gsm_fcs8[fcs ^ *c++]; | ||
368 | return fcs; | ||
369 | } | ||
370 | |||
371 | /** | ||
372 | * gsm_read_ea - read a byte into an EA | ||
373 | * @val: variable holding value | ||
374 | * c: byte going into the EA | ||
375 | * | ||
376 | * Processes one byte of an EA. Updates the passed variable | ||
377 | * and returns 1 if the EA is now completely read | ||
378 | */ | ||
379 | |||
380 | static int gsm_read_ea(unsigned int *val, u8 c) | ||
381 | { | ||
382 | /* Add the next 7 bits into the value */ | ||
383 | *val <<= 7; | ||
384 | *val |= c >> 1; | ||
385 | /* Was this the last byte of the EA 1 = yes*/ | ||
386 | return c & EA; | ||
387 | } | ||
388 | |||
389 | /** | ||
390 | * gsm_encode_modem - encode modem data bits | ||
391 | * @dlci: DLCI to encode from | ||
392 | * | ||
393 | * Returns the correct GSM encoded modem status bits (6 bit field) for | ||
394 | * the current status of the DLCI and attached tty object | ||
395 | */ | ||
396 | |||
397 | static u8 gsm_encode_modem(const struct gsm_dlci *dlci) | ||
398 | { | ||
399 | u8 modembits = 0; | ||
400 | /* FC is true flow control not modem bits */ | ||
401 | if (dlci->throttled) | ||
402 | modembits |= MDM_FC; | ||
403 | if (dlci->modem_tx & TIOCM_DTR) | ||
404 | modembits |= MDM_RTC; | ||
405 | if (dlci->modem_tx & TIOCM_RTS) | ||
406 | modembits |= MDM_RTR; | ||
407 | if (dlci->modem_tx & TIOCM_RI) | ||
408 | modembits |= MDM_IC; | ||
409 | if (dlci->modem_tx & TIOCM_CD) | ||
410 | modembits |= MDM_DV; | ||
411 | return modembits; | ||
412 | } | ||
413 | |||
414 | /** | ||
415 | * gsm_print_packet - display a frame for debug | ||
416 | * @hdr: header to print before decode | ||
417 | * @addr: address EA from the frame | ||
418 | * @cr: C/R bit from the frame | ||
419 | * @control: control including PF bit | ||
420 | * @data: following data bytes | ||
421 | * @dlen: length of data | ||
422 | * | ||
423 | * Displays a packet in human readable format for debugging purposes. The | ||
424 | * style is based on amateur radio LAP-B dump display. | ||
425 | */ | ||
426 | |||
427 | static void gsm_print_packet(const char *hdr, int addr, int cr, | ||
428 | u8 control, const u8 *data, int dlen) | ||
429 | { | ||
430 | if (!(debug & 1)) | ||
431 | return; | ||
432 | |||
433 | printk(KERN_INFO "%s %d) %c: ", hdr, addr, "RC"[cr]); | ||
434 | |||
435 | switch (control & ~PF) { | ||
436 | case SABM: | ||
437 | printk(KERN_CONT "SABM"); | ||
438 | break; | ||
439 | case UA: | ||
440 | printk(KERN_CONT "UA"); | ||
441 | break; | ||
442 | case DISC: | ||
443 | printk(KERN_CONT "DISC"); | ||
444 | break; | ||
445 | case DM: | ||
446 | printk(KERN_CONT "DM"); | ||
447 | break; | ||
448 | case UI: | ||
449 | printk(KERN_CONT "UI"); | ||
450 | break; | ||
451 | case UIH: | ||
452 | printk(KERN_CONT "UIH"); | ||
453 | break; | ||
454 | default: | ||
455 | if (!(control & 0x01)) { | ||
456 | printk(KERN_CONT "I N(S)%d N(R)%d", | ||
457 | (control & 0x0E) >> 1, (control & 0xE)>> 5); | ||
458 | } else switch (control & 0x0F) { | ||
459 | case RR: | ||
460 | printk("RR(%d)", (control & 0xE0) >> 5); | ||
461 | break; | ||
462 | case RNR: | ||
463 | printk("RNR(%d)", (control & 0xE0) >> 5); | ||
464 | break; | ||
465 | case REJ: | ||
466 | printk("REJ(%d)", (control & 0xE0) >> 5); | ||
467 | break; | ||
468 | default: | ||
469 | printk(KERN_CONT "[%02X]", control); | ||
470 | } | ||
471 | } | ||
472 | |||
473 | if (control & PF) | ||
474 | printk(KERN_CONT "(P)"); | ||
475 | else | ||
476 | printk(KERN_CONT "(F)"); | ||
477 | |||
478 | if (dlen) { | ||
479 | int ct = 0; | ||
480 | while (dlen--) { | ||
481 | if (ct % 8 == 0) | ||
482 | printk(KERN_CONT "\n "); | ||
483 | printk(KERN_CONT "%02X ", *data++); | ||
484 | ct++; | ||
485 | } | ||
486 | } | ||
487 | printk(KERN_CONT "\n"); | ||
488 | } | ||
489 | |||
490 | |||
491 | /* | ||
492 | * Link level transmission side | ||
493 | */ | ||
494 | |||
495 | /** | ||
496 | * gsm_stuff_packet - bytestuff a packet | ||
497 | * @ibuf: input | ||
498 | * @obuf: output | ||
499 | * @len: length of input | ||
500 | * | ||
501 | * Expand a buffer by bytestuffing it. The worst case size change | ||
502 | * is doubling and the caller is responsible for handing out | ||
503 | * suitable sized buffers. | ||
504 | */ | ||
505 | |||
506 | static int gsm_stuff_frame(const u8 *input, u8 *output, int len) | ||
507 | { | ||
508 | int olen = 0; | ||
509 | while (len--) { | ||
510 | if (*input == GSM1_SOF || *input == GSM1_ESCAPE | ||
511 | || *input == XON || *input == XOFF) { | ||
512 | *output++ = GSM1_ESCAPE; | ||
513 | *output++ = *input++ ^ GSM1_ESCAPE_BITS; | ||
514 | olen++; | ||
515 | } else | ||
516 | *output++ = *input++; | ||
517 | olen++; | ||
518 | } | ||
519 | return olen; | ||
520 | } | ||
521 | |||
522 | static void hex_packet(const unsigned char *p, int len) | ||
523 | { | ||
524 | int i; | ||
525 | for (i = 0; i < len; i++) { | ||
526 | if (i && (i % 16) == 0) | ||
527 | printk("\n"); | ||
528 | printk("%02X ", *p++); | ||
529 | } | ||
530 | printk("\n"); | ||
531 | } | ||
532 | |||
533 | /** | ||
534 | * gsm_send - send a control frame | ||
535 | * @gsm: our GSM mux | ||
536 | * @addr: address for control frame | ||
537 | * @cr: command/response bit | ||
538 | * @control: control byte including PF bit | ||
539 | * | ||
540 | * Format up and transmit a control frame. These do not go via the | ||
541 | * queueing logic as they should be transmitted ahead of data when | ||
542 | * they are needed. | ||
543 | * | ||
544 | * FIXME: Lock versus data TX path | ||
545 | */ | ||
546 | |||
547 | static void gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) | ||
548 | { | ||
549 | int len; | ||
550 | u8 cbuf[10]; | ||
551 | u8 ibuf[3]; | ||
552 | |||
553 | switch (gsm->encoding) { | ||
554 | case 0: | ||
555 | cbuf[0] = GSM0_SOF; | ||
556 | cbuf[1] = (addr << 2) | (cr << 1) | EA; | ||
557 | cbuf[2] = control; | ||
558 | cbuf[3] = EA; /* Length of data = 0 */ | ||
559 | cbuf[4] = 0xFF - gsm_fcs_add_block(INIT_FCS, cbuf + 1, 3); | ||
560 | cbuf[5] = GSM0_SOF; | ||
561 | len = 6; | ||
562 | break; | ||
563 | case 1: | ||
564 | case 2: | ||
565 | /* Control frame + packing (but not frame stuffing) in mode 1 */ | ||
566 | ibuf[0] = (addr << 2) | (cr << 1) | EA; | ||
567 | ibuf[1] = control; | ||
568 | ibuf[2] = 0xFF - gsm_fcs_add_block(INIT_FCS, ibuf, 2); | ||
569 | /* Stuffing may double the size worst case */ | ||
570 | len = gsm_stuff_frame(ibuf, cbuf + 1, 3); | ||
571 | /* Now add the SOF markers */ | ||
572 | cbuf[0] = GSM1_SOF; | ||
573 | cbuf[len + 1] = GSM1_SOF; | ||
574 | /* FIXME: we can omit the lead one in many cases */ | ||
575 | len += 2; | ||
576 | break; | ||
577 | default: | ||
578 | WARN_ON(1); | ||
579 | return; | ||
580 | } | ||
581 | gsm->output(gsm, cbuf, len); | ||
582 | gsm_print_packet("-->", addr, cr, control, NULL, 0); | ||
583 | } | ||
584 | |||
585 | /** | ||
586 | * gsm_response - send a control response | ||
587 | * @gsm: our GSM mux | ||
588 | * @addr: address for control frame | ||
589 | * @control: control byte including PF bit | ||
590 | * | ||
591 | * Format up and transmit a link level response frame. | ||
592 | */ | ||
593 | |||
594 | static inline void gsm_response(struct gsm_mux *gsm, int addr, int control) | ||
595 | { | ||
596 | gsm_send(gsm, addr, 0, control); | ||
597 | } | ||
598 | |||
599 | /** | ||
600 | * gsm_command - send a control command | ||
601 | * @gsm: our GSM mux | ||
602 | * @addr: address for control frame | ||
603 | * @control: control byte including PF bit | ||
604 | * | ||
605 | * Format up and transmit a link level command frame. | ||
606 | */ | ||
607 | |||
608 | static inline void gsm_command(struct gsm_mux *gsm, int addr, int control) | ||
609 | { | ||
610 | gsm_send(gsm, addr, 1, control); | ||
611 | } | ||
612 | |||
613 | /* Data transmission */ | ||
614 | |||
615 | #define HDR_LEN 6 /* ADDR CTRL [LEN.2] DATA FCS */ | ||
616 | |||
617 | /** | ||
618 | * gsm_data_alloc - allocate data frame | ||
619 | * @gsm: GSM mux | ||
620 | * @addr: DLCI address | ||
621 | * @len: length excluding header and FCS | ||
622 | * @ctrl: control byte | ||
623 | * | ||
624 | * Allocate a new data buffer for sending frames with data. Space is left | ||
625 | * at the front for header bytes but that is treated as an implementation | ||
626 | * detail and not for the high level code to use | ||
627 | */ | ||
628 | |||
629 | static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len, | ||
630 | u8 ctrl) | ||
631 | { | ||
632 | struct gsm_msg *m = kmalloc(sizeof(struct gsm_msg) + len + HDR_LEN, | ||
633 | GFP_ATOMIC); | ||
634 | if (m == NULL) | ||
635 | return NULL; | ||
636 | m->data = m->buffer + HDR_LEN - 1; /* Allow for FCS */ | ||
637 | m->len = len; | ||
638 | m->addr = addr; | ||
639 | m->ctrl = ctrl; | ||
640 | m->next = NULL; | ||
641 | return m; | ||
642 | } | ||
643 | |||
644 | /** | ||
645 | * gsm_data_kick - poke the queue | ||
646 | * @gsm: GSM Mux | ||
647 | * | ||
648 | * The tty device has called us to indicate that room has appeared in | ||
649 | * the transmit queue. Ram more data into the pipe if we have any | ||
650 | * | ||
651 | * FIXME: lock against link layer control transmissions | ||
652 | */ | ||
653 | |||
654 | static void gsm_data_kick(struct gsm_mux *gsm) | ||
655 | { | ||
656 | struct gsm_msg *msg = gsm->tx_head; | ||
657 | int len; | ||
658 | int skip_sof = 0; | ||
659 | |||
660 | /* FIXME: We need to apply this solely to data messages */ | ||
661 | if (gsm->constipated) | ||
662 | return; | ||
663 | |||
664 | while (gsm->tx_head != NULL) { | ||
665 | msg = gsm->tx_head; | ||
666 | if (gsm->encoding != 0) { | ||
667 | gsm->txframe[0] = GSM1_SOF; | ||
668 | len = gsm_stuff_frame(msg->data, | ||
669 | gsm->txframe + 1, msg->len); | ||
670 | gsm->txframe[len + 1] = GSM1_SOF; | ||
671 | len += 2; | ||
672 | } else { | ||
673 | gsm->txframe[0] = GSM0_SOF; | ||
674 | memcpy(gsm->txframe + 1 , msg->data, msg->len); | ||
675 | gsm->txframe[msg->len + 1] = GSM0_SOF; | ||
676 | len = msg->len + 2; | ||
677 | } | ||
678 | |||
679 | if (debug & 4) { | ||
680 | printk("gsm_data_kick: \n"); | ||
681 | hex_packet(gsm->txframe, len); | ||
682 | } | ||
683 | |||
684 | if (gsm->output(gsm, gsm->txframe + skip_sof, | ||
685 | len - skip_sof) < 0) | ||
686 | break; | ||
687 | /* FIXME: Can eliminate one SOF in many more cases */ | ||
688 | gsm->tx_head = msg->next; | ||
689 | if (gsm->tx_head == NULL) | ||
690 | gsm->tx_tail = NULL; | ||
691 | gsm->tx_bytes -= msg->len; | ||
692 | kfree(msg); | ||
693 | /* For a burst of frames skip the extra SOF within the | ||
694 | burst */ | ||
695 | skip_sof = 1; | ||
696 | } | ||
697 | } | ||
698 | |||
699 | /** | ||
700 | * __gsm_data_queue - queue a UI or UIH frame | ||
701 | * @dlci: DLCI sending the data | ||
702 | * @msg: message queued | ||
703 | * | ||
704 | * Add data to the transmit queue and try and get stuff moving | ||
705 | * out of the mux tty if not already doing so. The Caller must hold | ||
706 | * the gsm tx lock. | ||
707 | */ | ||
708 | |||
709 | static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) | ||
710 | { | ||
711 | struct gsm_mux *gsm = dlci->gsm; | ||
712 | u8 *dp = msg->data; | ||
713 | u8 *fcs = dp + msg->len; | ||
714 | |||
715 | /* Fill in the header */ | ||
716 | if (gsm->encoding == 0) { | ||
717 | if (msg->len < 128) | ||
718 | *--dp = (msg->len << 1) | EA; | ||
719 | else { | ||
720 | *--dp = (msg->len >> 6) | EA; | ||
721 | *--dp = (msg->len & 127) << 1; | ||
722 | } | ||
723 | } | ||
724 | |||
725 | *--dp = msg->ctrl; | ||
726 | if (gsm->initiator) | ||
727 | *--dp = (msg->addr << 2) | 2 | EA; | ||
728 | else | ||
729 | *--dp = (msg->addr << 2) | EA; | ||
730 | *fcs = gsm_fcs_add_block(INIT_FCS, dp , msg->data - dp); | ||
731 | /* Ugly protocol layering violation */ | ||
732 | if (msg->ctrl == UI || msg->ctrl == (UI|PF)) | ||
733 | *fcs = gsm_fcs_add_block(*fcs, msg->data, msg->len); | ||
734 | *fcs = 0xFF - *fcs; | ||
735 | |||
736 | gsm_print_packet("Q> ", msg->addr, gsm->initiator, msg->ctrl, | ||
737 | msg->data, msg->len); | ||
738 | |||
739 | /* Move the header back and adjust the length, also allow for the FCS | ||
740 | now tacked on the end */ | ||
741 | msg->len += (msg->data - dp) + 1; | ||
742 | msg->data = dp; | ||
743 | |||
744 | /* Add to the actual output queue */ | ||
745 | if (gsm->tx_tail) | ||
746 | gsm->tx_tail->next = msg; | ||
747 | else | ||
748 | gsm->tx_head = msg; | ||
749 | gsm->tx_tail = msg; | ||
750 | gsm->tx_bytes += msg->len; | ||
751 | gsm_data_kick(gsm); | ||
752 | } | ||
753 | |||
754 | /** | ||
755 | * gsm_data_queue - queue a UI or UIH frame | ||
756 | * @dlci: DLCI sending the data | ||
757 | * @msg: message queued | ||
758 | * | ||
759 | * Add data to the transmit queue and try and get stuff moving | ||
760 | * out of the mux tty if not already doing so. Take the | ||
761 | * the gsm tx lock and dlci lock. | ||
762 | */ | ||
763 | |||
764 | static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) | ||
765 | { | ||
766 | unsigned long flags; | ||
767 | spin_lock_irqsave(&dlci->gsm->tx_lock, flags); | ||
768 | __gsm_data_queue(dlci, msg); | ||
769 | spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); | ||
770 | } | ||
771 | |||
772 | /** | ||
773 | * gsm_dlci_data_output - try and push data out of a DLCI | ||
774 | * @gsm: mux | ||
775 | * @dlci: the DLCI to pull data from | ||
776 | * | ||
777 | * Pull data from a DLCI and send it into the transmit queue if there | ||
778 | * is data. Keep to the MRU of the mux. This path handles the usual tty | ||
779 | * interface which is a byte stream with optional modem data. | ||
780 | * | ||
781 | * Caller must hold the tx_lock of the mux. | ||
782 | */ | ||
783 | |||
784 | static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) | ||
785 | { | ||
786 | struct gsm_msg *msg; | ||
787 | u8 *dp; | ||
788 | int len, size; | ||
789 | int h = dlci->adaption - 1; | ||
790 | |||
791 | len = kfifo_len(dlci->fifo); | ||
792 | if (len == 0) | ||
793 | return 0; | ||
794 | |||
795 | /* MTU/MRU count only the data bits */ | ||
796 | if (len > gsm->mtu) | ||
797 | len = gsm->mtu; | ||
798 | |||
799 | size = len + h; | ||
800 | |||
801 | msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); | ||
802 | /* FIXME: need a timer or something to kick this so it can't | ||
803 | get stuck with no work outstanding and no buffer free */ | ||
804 | if (msg == NULL) | ||
805 | return -ENOMEM; | ||
806 | dp = msg->data; | ||
807 | switch (dlci->adaption) { | ||
808 | case 1: /* Unstructured */ | ||
809 | break; | ||
810 | case 2: /* Unstructed with modem bits. Always one byte as we never | ||
811 | send inline break data */ | ||
812 | *dp += gsm_encode_modem(dlci); | ||
813 | len--; | ||
814 | break; | ||
815 | } | ||
816 | WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len); | ||
817 | __gsm_data_queue(dlci, msg); | ||
818 | /* Bytes of data we used up */ | ||
819 | return size; | ||
820 | } | ||
821 | |||
822 | /** | ||
823 | * gsm_dlci_data_output_framed - try and push data out of a DLCI | ||
824 | * @gsm: mux | ||
825 | * @dlci: the DLCI to pull data from | ||
826 | * | ||
827 | * Pull data from a DLCI and send it into the transmit queue if there | ||
828 | * is data. Keep to the MRU of the mux. This path handles framed data | ||
829 | * queued as skbuffs to the DLCI. | ||
830 | * | ||
831 | * Caller must hold the tx_lock of the mux. | ||
832 | */ | ||
833 | |||
834 | static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, | ||
835 | struct gsm_dlci *dlci) | ||
836 | { | ||
837 | struct gsm_msg *msg; | ||
838 | u8 *dp; | ||
839 | int len, size; | ||
840 | int last = 0, first = 0; | ||
841 | int overhead = 0; | ||
842 | |||
843 | /* One byte per frame is used for B/F flags */ | ||
844 | if (dlci->adaption == 4) | ||
845 | overhead = 1; | ||
846 | |||
847 | /* dlci->skb is locked by tx_lock */ | ||
848 | if (dlci->skb == NULL) { | ||
849 | dlci->skb = skb_dequeue(&dlci->skb_list); | ||
850 | if (dlci->skb == NULL) | ||
851 | return 0; | ||
852 | first = 1; | ||
853 | } | ||
854 | len = dlci->skb->len + overhead; | ||
855 | |||
856 | /* MTU/MRU count only the data bits */ | ||
857 | if (len > gsm->mtu) { | ||
858 | if (dlci->adaption == 3) { | ||
859 | /* Over long frame, bin it */ | ||
860 | kfree_skb(dlci->skb); | ||
861 | dlci->skb = NULL; | ||
862 | return 0; | ||
863 | } | ||
864 | len = gsm->mtu; | ||
865 | } else | ||
866 | last = 1; | ||
867 | |||
868 | size = len + overhead; | ||
869 | msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); | ||
870 | |||
871 | /* FIXME: need a timer or something to kick this so it can't | ||
872 | get stuck with no work outstanding and no buffer free */ | ||
873 | if (msg == NULL) | ||
874 | return -ENOMEM; | ||
875 | dp = msg->data; | ||
876 | |||
877 | if (dlci->adaption == 4) { /* Interruptible framed (Packetised Data) */ | ||
878 | /* Flag byte to carry the start/end info */ | ||
879 | *dp++ = last << 7 | first << 6 | 1; /* EA */ | ||
880 | len--; | ||
881 | } | ||
882 | memcpy(dp, skb_pull(dlci->skb, len), len); | ||
883 | __gsm_data_queue(dlci, msg); | ||
884 | if (last) | ||
885 | dlci->skb = NULL; | ||
886 | return size; | ||
887 | } | ||
888 | |||
889 | /** | ||
890 | * gsm_dlci_data_sweep - look for data to send | ||
891 | * @gsm: the GSM mux | ||
892 | * | ||
893 | * Sweep the GSM mux channels in priority order looking for ones with | ||
894 | * data to send. We could do with optimising this scan a bit. We aim | ||
895 | * to fill the queue totally or up to TX_THRESH_HI bytes. Once we hit | ||
896 | * TX_THRESH_LO we get called again | ||
897 | * | ||
898 | * FIXME: We should round robin between groups and in theory you can | ||
899 | * renegotiate DLCI priorities with optional stuff. Needs optimising. | ||
900 | */ | ||
901 | |||
902 | static void gsm_dlci_data_sweep(struct gsm_mux *gsm) | ||
903 | { | ||
904 | int len; | ||
905 | /* Priority ordering: We should do priority with RR of the groups */ | ||
906 | int i = 1; | ||
907 | unsigned long flags; | ||
908 | |||
909 | spin_lock_irqsave(&gsm->tx_lock, flags); | ||
910 | while (i < NUM_DLCI) { | ||
911 | struct gsm_dlci *dlci; | ||
912 | |||
913 | if (gsm->tx_bytes > TX_THRESH_HI) | ||
914 | break; | ||
915 | dlci = gsm->dlci[i]; | ||
916 | if (dlci == NULL || dlci->constipated) { | ||
917 | i++; | ||
918 | continue; | ||
919 | } | ||
920 | if (dlci->adaption < 3) | ||
921 | len = gsm_dlci_data_output(gsm, dlci); | ||
922 | else | ||
923 | len = gsm_dlci_data_output_framed(gsm, dlci); | ||
924 | if (len < 0) | ||
925 | return; | ||
926 | /* DLCI empty - try the next */ | ||
927 | if (len == 0) | ||
928 | i++; | ||
929 | } | ||
930 | spin_unlock_irqrestore(&gsm->tx_lock, flags); | ||
931 | } | ||
932 | |||
933 | /** | ||
934 | * gsm_dlci_data_kick - transmit if possible | ||
935 | * @dlci: DLCI to kick | ||
936 | * | ||
937 | * Transmit data from this DLCI if the queue is empty. We can't rely on | ||
938 | * a tty wakeup except when we filled the pipe so we need to fire off | ||
939 | * new data ourselves in other cases. | ||
940 | */ | ||
941 | |||
942 | static void gsm_dlci_data_kick(struct gsm_dlci *dlci) | ||
943 | { | ||
944 | unsigned long flags; | ||
945 | |||
946 | spin_lock_irqsave(&dlci->gsm->tx_lock, flags); | ||
947 | /* If we have nothing running then we need to fire up */ | ||
948 | if (dlci->gsm->tx_bytes == 0) | ||
949 | gsm_dlci_data_output(dlci->gsm, dlci); | ||
950 | else if (dlci->gsm->tx_bytes < TX_THRESH_LO) | ||
951 | gsm_dlci_data_sweep(dlci->gsm); | ||
952 | spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); | ||
953 | } | ||
954 | |||
955 | /* | ||
956 | * Control message processing | ||
957 | */ | ||
958 | |||
959 | |||
960 | /** | ||
961 | * gsm_control_reply - send a response frame to a control | ||
962 | * @gsm: gsm channel | ||
963 | * @cmd: the command to use | ||
964 | * @data: data to follow encoded info | ||
965 | * @dlen: length of data | ||
966 | * | ||
967 | * Encode up and queue a UI/UIH frame containing our response. | ||
968 | */ | ||
969 | |||
970 | static void gsm_control_reply(struct gsm_mux *gsm, int cmd, u8 *data, | ||
971 | int dlen) | ||
972 | { | ||
973 | struct gsm_msg *msg; | ||
974 | msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype); | ||
975 | msg->data[0] = (cmd & 0xFE) << 1 | EA; /* Clear C/R */ | ||
976 | msg->data[1] = (dlen << 1) | EA; | ||
977 | memcpy(msg->data + 2, data, dlen); | ||
978 | gsm_data_queue(gsm->dlci[0], msg); | ||
979 | } | ||
980 | |||
981 | /** | ||
982 | * gsm_process_modem - process received modem status | ||
983 | * @tty: virtual tty bound to the DLCI | ||
984 | * @dlci: DLCI to affect | ||
985 | * @modem: modem bits (full EA) | ||
986 | * | ||
987 | * Used when a modem control message or line state inline in adaption | ||
988 | * layer 2 is processed. Sort out the local modem state and throttles | ||
989 | */ | ||
990 | |||
991 | static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci, | ||
992 | u32 modem) | ||
993 | { | ||
994 | int mlines = 0; | ||
995 | u8 brk = modem >> 6; | ||
996 | |||
997 | /* Flow control/ready to communicate */ | ||
998 | if (modem & MDM_FC) { | ||
999 | /* Need to throttle our output on this device */ | ||
1000 | dlci->constipated = 1; | ||
1001 | } | ||
1002 | if (modem & MDM_RTC) { | ||
1003 | mlines |= TIOCM_DSR | TIOCM_DTR; | ||
1004 | dlci->constipated = 0; | ||
1005 | gsm_dlci_data_kick(dlci); | ||
1006 | } | ||
1007 | /* Map modem bits */ | ||
1008 | if (modem & MDM_RTR) | ||
1009 | mlines |= TIOCM_RTS | TIOCM_CTS; | ||
1010 | if (modem & MDM_IC) | ||
1011 | mlines |= TIOCM_RI; | ||
1012 | if (modem & MDM_DV) | ||
1013 | mlines |= TIOCM_CD; | ||
1014 | |||
1015 | /* Carrier drop -> hangup */ | ||
1016 | if (tty) { | ||
1017 | if ((mlines & TIOCM_CD) == 0 && (dlci->modem_rx & TIOCM_CD)) | ||
1018 | if (!(tty->termios->c_cflag & CLOCAL)) | ||
1019 | tty_hangup(tty); | ||
1020 | if (brk & 0x01) | ||
1021 | tty_insert_flip_char(tty, 0, TTY_BREAK); | ||
1022 | } | ||
1023 | dlci->modem_rx = mlines; | ||
1024 | } | ||
1025 | |||
1026 | /** | ||
1027 | * gsm_control_modem - modem status received | ||
1028 | * @gsm: GSM channel | ||
1029 | * @data: data following command | ||
1030 | * @clen: command length | ||
1031 | * | ||
1032 | * We have received a modem status control message. This is used by | ||
1033 | * the GSM mux protocol to pass virtual modem line status and optionally | ||
1034 | * to indicate break signals. Unpack it, convert to Linux representation | ||
1035 | * and if need be stuff a break message down the tty. | ||
1036 | */ | ||
1037 | |||
1038 | static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen) | ||
1039 | { | ||
1040 | unsigned int addr = 0; | ||
1041 | unsigned int modem = 0; | ||
1042 | struct gsm_dlci *dlci; | ||
1043 | int len = clen; | ||
1044 | u8 *dp = data; | ||
1045 | struct tty_struct *tty; | ||
1046 | |||
1047 | while (gsm_read_ea(&addr, *dp++) == 0) { | ||
1048 | len--; | ||
1049 | if (len == 0) | ||
1050 | return; | ||
1051 | } | ||
1052 | /* Must be at least one byte following the EA */ | ||
1053 | len--; | ||
1054 | if (len <= 0) | ||
1055 | return; | ||
1056 | |||
1057 | addr >>= 1; | ||
1058 | /* Closed port, or invalid ? */ | ||
1059 | if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) | ||
1060 | return; | ||
1061 | dlci = gsm->dlci[addr]; | ||
1062 | |||
1063 | while (gsm_read_ea(&modem, *dp++) == 0) { | ||
1064 | len--; | ||
1065 | if (len == 0) | ||
1066 | return; | ||
1067 | } | ||
1068 | tty = tty_port_tty_get(&dlci->port); | ||
1069 | gsm_process_modem(tty, dlci, modem); | ||
1070 | if (tty) { | ||
1071 | tty_wakeup(tty); | ||
1072 | tty_kref_put(tty); | ||
1073 | } | ||
1074 | gsm_control_reply(gsm, CMD_MSC, data, clen); | ||
1075 | } | ||
1076 | |||
1077 | /** | ||
1078 | * gsm_control_rls - remote line status | ||
1079 | * @gsm: GSM channel | ||
1080 | * @data: data bytes | ||
1081 | * @clen: data length | ||
1082 | * | ||
1083 | * The modem sends us a two byte message on the control channel whenever | ||
1084 | * it wishes to send us an error state from the virtual link. Stuff | ||
1085 | * this into the uplink tty if present | ||
1086 | */ | ||
1087 | |||
1088 | static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen) | ||
1089 | { | ||
1090 | struct tty_struct *tty; | ||
1091 | unsigned int addr = 0 ; | ||
1092 | u8 bits; | ||
1093 | int len = clen; | ||
1094 | u8 *dp = data; | ||
1095 | |||
1096 | while (gsm_read_ea(&addr, *dp++) == 0) { | ||
1097 | len--; | ||
1098 | if (len == 0) | ||
1099 | return; | ||
1100 | } | ||
1101 | /* Must be at least one byte following ea */ | ||
1102 | len--; | ||
1103 | if (len <= 0) | ||
1104 | return; | ||
1105 | addr >>= 1; | ||
1106 | /* Closed port, or invalid ? */ | ||
1107 | if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) | ||
1108 | return; | ||
1109 | /* No error ? */ | ||
1110 | bits = *dp; | ||
1111 | if ((bits & 1) == 0) | ||
1112 | return; | ||
1113 | /* See if we have an uplink tty */ | ||
1114 | tty = tty_port_tty_get(&gsm->dlci[addr]->port); | ||
1115 | |||
1116 | if (tty) { | ||
1117 | if (bits & 2) | ||
1118 | tty_insert_flip_char(tty, 0, TTY_OVERRUN); | ||
1119 | if (bits & 4) | ||
1120 | tty_insert_flip_char(tty, 0, TTY_PARITY); | ||
1121 | if (bits & 8) | ||
1122 | tty_insert_flip_char(tty, 0, TTY_FRAME); | ||
1123 | tty_flip_buffer_push(tty); | ||
1124 | tty_kref_put(tty); | ||
1125 | } | ||
1126 | gsm_control_reply(gsm, CMD_RLS, data, clen); | ||
1127 | } | ||
1128 | |||
1129 | static void gsm_dlci_begin_close(struct gsm_dlci *dlci); | ||
1130 | |||
1131 | /** | ||
1132 | * gsm_control_message - DLCI 0 control processing | ||
1133 | * @gsm: our GSM mux | ||
1134 | * @command: the command EA | ||
1135 | * @data: data beyond the command/length EAs | ||
1136 | * @clen: length | ||
1137 | * | ||
1138 | * Input processor for control messages from the other end of the link. | ||
1139 | * Processes the incoming request and queues a response frame or an | ||
1140 | * NSC response if not supported | ||
1141 | */ | ||
1142 | |||
1143 | static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, | ||
1144 | u8 *data, int clen) | ||
1145 | { | ||
1146 | u8 buf[1]; | ||
1147 | switch (command) { | ||
1148 | case CMD_CLD: { | ||
1149 | struct gsm_dlci *dlci = gsm->dlci[0]; | ||
1150 | /* Modem wishes to close down */ | ||
1151 | if (dlci) { | ||
1152 | dlci->dead = 1; | ||
1153 | gsm->dead = 1; | ||
1154 | gsm_dlci_begin_close(dlci); | ||
1155 | } | ||
1156 | } | ||
1157 | break; | ||
1158 | case CMD_TEST: | ||
1159 | /* Modem wishes to test, reply with the data */ | ||
1160 | gsm_control_reply(gsm, CMD_TEST, data, clen); | ||
1161 | break; | ||
1162 | case CMD_FCON: | ||
1163 | /* Modem wants us to STFU */ | ||
1164 | gsm->constipated = 1; | ||
1165 | gsm_control_reply(gsm, CMD_FCON, NULL, 0); | ||
1166 | break; | ||
1167 | case CMD_FCOFF: | ||
1168 | /* Modem can accept data again */ | ||
1169 | gsm->constipated = 0; | ||
1170 | gsm_control_reply(gsm, CMD_FCOFF, NULL, 0); | ||
1171 | /* Kick the link in case it is idling */ | ||
1172 | gsm_data_kick(gsm); | ||
1173 | break; | ||
1174 | case CMD_MSC: | ||
1175 | /* Out of band modem line change indicator for a DLCI */ | ||
1176 | gsm_control_modem(gsm, data, clen); | ||
1177 | break; | ||
1178 | case CMD_RLS: | ||
1179 | /* Out of band error reception for a DLCI */ | ||
1180 | gsm_control_rls(gsm, data, clen); | ||
1181 | break; | ||
1182 | case CMD_PSC: | ||
1183 | /* Modem wishes to enter power saving state */ | ||
1184 | gsm_control_reply(gsm, CMD_PSC, NULL, 0); | ||
1185 | break; | ||
1186 | /* Optional unsupported commands */ | ||
1187 | case CMD_PN: /* Parameter negotiation */ | ||
1188 | case CMD_RPN: /* Remote port negotation */ | ||
1189 | case CMD_SNC: /* Service negotation command */ | ||
1190 | default: | ||
1191 | /* Reply to bad commands with an NSC */ | ||
1192 | buf[0] = command; | ||
1193 | gsm_control_reply(gsm, CMD_NSC, buf, 1); | ||
1194 | break; | ||
1195 | } | ||
1196 | } | ||
1197 | |||
1198 | /** | ||
1199 | * gsm_control_response - process a response to our control | ||
1200 | * @gsm: our GSM mux | ||
1201 | * @command: the command (response) EA | ||
1202 | * @data: data beyond the command/length EA | ||
1203 | * @clen: length | ||
1204 | * | ||
1205 | * Process a response to an outstanding command. We only allow a single | ||
1206 | * control message in flight so this is fairly easy. All the clean up | ||
1207 | * is done by the caller, we just update the fields, flag it as done | ||
1208 | * and return | ||
1209 | */ | ||
1210 | |||
1211 | static void gsm_control_response(struct gsm_mux *gsm, unsigned int command, | ||
1212 | u8 *data, int clen) | ||
1213 | { | ||
1214 | struct gsm_control *ctrl; | ||
1215 | unsigned long flags; | ||
1216 | |||
1217 | spin_lock_irqsave(&gsm->control_lock, flags); | ||
1218 | |||
1219 | ctrl = gsm->pending_cmd; | ||
1220 | /* Does the reply match our command */ | ||
1221 | command |= 1; | ||
1222 | if (ctrl != NULL && (command == ctrl->cmd || command == CMD_NSC)) { | ||
1223 | /* Our command was replied to, kill the retry timer */ | ||
1224 | del_timer(&gsm->t2_timer); | ||
1225 | gsm->pending_cmd = NULL; | ||
1226 | /* Rejected by the other end */ | ||
1227 | if (command == CMD_NSC) | ||
1228 | ctrl->error = -EOPNOTSUPP; | ||
1229 | ctrl->done = 1; | ||
1230 | wake_up(&gsm->event); | ||
1231 | } | ||
1232 | spin_unlock_irqrestore(&gsm->control_lock, flags); | ||
1233 | } | ||
1234 | |||
1235 | /** | ||
1236 | * gsm_control_transmit - send control packet | ||
1237 | * @gsm: gsm mux | ||
1238 | * @ctrl: frame to send | ||
1239 | * | ||
1240 | * Send out a pending control command (called under control lock) | ||
1241 | */ | ||
1242 | |||
1243 | static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl) | ||
1244 | { | ||
1245 | struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1, | ||
1246 | gsm->ftype|PF); | ||
1247 | if (msg == NULL) | ||
1248 | return; | ||
1249 | msg->data[0] = (ctrl->cmd << 1) | 2 | EA; /* command */ | ||
1250 | memcpy(msg->data + 1, ctrl->data, ctrl->len); | ||
1251 | gsm_data_queue(gsm->dlci[0], msg); | ||
1252 | } | ||
1253 | |||
1254 | /** | ||
1255 | * gsm_control_retransmit - retransmit a control frame | ||
1256 | * @data: pointer to our gsm object | ||
1257 | * | ||
1258 | * Called off the T2 timer expiry in order to retransmit control frames | ||
1259 | * that have been lost in the system somewhere. The control_lock protects | ||
1260 | * us from colliding with another sender or a receive completion event. | ||
1261 | * In that situation the timer may still occur in a small window but | ||
1262 | * gsm->pending_cmd will be NULL and we just let the timer expire. | ||
1263 | */ | ||
1264 | |||
1265 | static void gsm_control_retransmit(unsigned long data) | ||
1266 | { | ||
1267 | struct gsm_mux *gsm = (struct gsm_mux *)data; | ||
1268 | struct gsm_control *ctrl; | ||
1269 | unsigned long flags; | ||
1270 | spin_lock_irqsave(&gsm->control_lock, flags); | ||
1271 | ctrl = gsm->pending_cmd; | ||
1272 | if (ctrl) { | ||
1273 | gsm->cretries--; | ||
1274 | if (gsm->cretries == 0) { | ||
1275 | gsm->pending_cmd = NULL; | ||
1276 | ctrl->error = -ETIMEDOUT; | ||
1277 | ctrl->done = 1; | ||
1278 | spin_unlock_irqrestore(&gsm->control_lock, flags); | ||
1279 | wake_up(&gsm->event); | ||
1280 | return; | ||
1281 | } | ||
1282 | gsm_control_transmit(gsm, ctrl); | ||
1283 | mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); | ||
1284 | } | ||
1285 | spin_unlock_irqrestore(&gsm->control_lock, flags); | ||
1286 | } | ||
1287 | |||
1288 | /** | ||
1289 | * gsm_control_send - send a control frame on DLCI 0 | ||
1290 | * @gsm: the GSM channel | ||
1291 | * @command: command to send including CR bit | ||
1292 | * @data: bytes of data (must be kmalloced) | ||
1293 | * @len: length of the block to send | ||
1294 | * | ||
1295 | * Queue and dispatch a control command. Only one command can be | ||
1296 | * active at a time. In theory more can be outstanding but the matching | ||
1297 | * gets really complicated so for now stick to one outstanding. | ||
1298 | */ | ||
1299 | |||
1300 | static struct gsm_control *gsm_control_send(struct gsm_mux *gsm, | ||
1301 | unsigned int command, u8 *data, int clen) | ||
1302 | { | ||
1303 | struct gsm_control *ctrl = kzalloc(sizeof(struct gsm_control), | ||
1304 | GFP_KERNEL); | ||
1305 | unsigned long flags; | ||
1306 | if (ctrl == NULL) | ||
1307 | return NULL; | ||
1308 | retry: | ||
1309 | wait_event(gsm->event, gsm->pending_cmd == NULL); | ||
1310 | spin_lock_irqsave(&gsm->control_lock, flags); | ||
1311 | if (gsm->pending_cmd != NULL) { | ||
1312 | spin_unlock_irqrestore(&gsm->control_lock, flags); | ||
1313 | goto retry; | ||
1314 | } | ||
1315 | ctrl->cmd = command; | ||
1316 | ctrl->data = data; | ||
1317 | ctrl->len = clen; | ||
1318 | gsm->pending_cmd = ctrl; | ||
1319 | gsm->cretries = gsm->n2; | ||
1320 | mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); | ||
1321 | gsm_control_transmit(gsm, ctrl); | ||
1322 | spin_unlock_irqrestore(&gsm->control_lock, flags); | ||
1323 | return ctrl; | ||
1324 | } | ||
1325 | |||
1326 | /** | ||
1327 | * gsm_control_wait - wait for a control to finish | ||
1328 | * @gsm: GSM mux | ||
1329 | * @control: control we are waiting on | ||
1330 | * | ||
1331 | * Waits for the control to complete or time out. Frees any used | ||
1332 | * resources and returns 0 for success, or an error if the remote | ||
1333 | * rejected or ignored the request. | ||
1334 | */ | ||
1335 | |||
1336 | static int gsm_control_wait(struct gsm_mux *gsm, struct gsm_control *control) | ||
1337 | { | ||
1338 | int err; | ||
1339 | wait_event(gsm->event, control->done == 1); | ||
1340 | err = control->error; | ||
1341 | kfree(control); | ||
1342 | return err; | ||
1343 | } | ||
1344 | |||
1345 | |||
1346 | /* | ||
1347 | * DLCI level handling: Needs krefs | ||
1348 | */ | ||
1349 | |||
1350 | /* | ||
1351 | * State transitions and timers | ||
1352 | */ | ||
1353 | |||
1354 | /** | ||
1355 | * gsm_dlci_close - a DLCI has closed | ||
1356 | * @dlci: DLCI that closed | ||
1357 | * | ||
1358 | * Perform processing when moving a DLCI into closed state. If there | ||
1359 | * is an attached tty this is hung up | ||
1360 | */ | ||
1361 | |||
1362 | static void gsm_dlci_close(struct gsm_dlci *dlci) | ||
1363 | { | ||
1364 | del_timer(&dlci->t1); | ||
1365 | if (debug & 8) | ||
1366 | printk("DLCI %d goes closed.\n", dlci->addr); | ||
1367 | dlci->state = DLCI_CLOSED; | ||
1368 | if (dlci->addr != 0) { | ||
1369 | struct tty_struct *tty = tty_port_tty_get(&dlci->port); | ||
1370 | if (tty) { | ||
1371 | tty_hangup(tty); | ||
1372 | tty_kref_put(tty); | ||
1373 | } | ||
1374 | kfifo_reset(dlci->fifo); | ||
1375 | } else | ||
1376 | dlci->gsm->dead = 1; | ||
1377 | wake_up(&dlci->gsm->event); | ||
1378 | /* A DLCI 0 close is a MUX termination so we need to kick that | ||
1379 | back to userspace somehow */ | ||
1380 | } | ||
1381 | |||
1382 | /** | ||
1383 | * gsm_dlci_open - a DLCI has opened | ||
1384 | * @dlci: DLCI that opened | ||
1385 | * | ||
1386 | * Perform processing when moving a DLCI into open state. | ||
1387 | */ | ||
1388 | |||
1389 | static void gsm_dlci_open(struct gsm_dlci *dlci) | ||
1390 | { | ||
1391 | /* Note that SABM UA .. SABM UA first UA lost can mean that we go | ||
1392 | open -> open */ | ||
1393 | del_timer(&dlci->t1); | ||
1394 | /* This will let a tty open continue */ | ||
1395 | dlci->state = DLCI_OPEN; | ||
1396 | if (debug & 8) | ||
1397 | printk("DLCI %d goes open.\n", dlci->addr); | ||
1398 | wake_up(&dlci->gsm->event); | ||
1399 | } | ||
1400 | |||
1401 | /** | ||
1402 | * gsm_dlci_t1 - T1 timer expiry | ||
1403 | * @dlci: DLCI that opened | ||
1404 | * | ||
1405 | * The T1 timer handles retransmits of control frames (essentially of | ||
1406 | * SABM and DISC). We resend the command until the retry count runs out | ||
1407 | * in which case an opening port goes back to closed and a closing port | ||
1408 | * is simply put into closed state (any further frames from the other | ||
1409 | * end will get a DM response) | ||
1410 | */ | ||
1411 | |||
1412 | static void gsm_dlci_t1(unsigned long data) | ||
1413 | { | ||
1414 | struct gsm_dlci *dlci = (struct gsm_dlci *)data; | ||
1415 | struct gsm_mux *gsm = dlci->gsm; | ||
1416 | |||
1417 | switch (dlci->state) { | ||
1418 | case DLCI_OPENING: | ||
1419 | dlci->retries--; | ||
1420 | if (dlci->retries) { | ||
1421 | gsm_command(dlci->gsm, dlci->addr, SABM|PF); | ||
1422 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | ||
1423 | } else | ||
1424 | gsm_dlci_close(dlci); | ||
1425 | break; | ||
1426 | case DLCI_CLOSING: | ||
1427 | dlci->retries--; | ||
1428 | if (dlci->retries) { | ||
1429 | gsm_command(dlci->gsm, dlci->addr, DISC|PF); | ||
1430 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | ||
1431 | } else | ||
1432 | gsm_dlci_close(dlci); | ||
1433 | break; | ||
1434 | } | ||
1435 | } | ||
1436 | |||
1437 | /** | ||
1438 | * gsm_dlci_begin_open - start channel open procedure | ||
1439 | * @dlci: DLCI to open | ||
1440 | * | ||
1441 | * Commence opening a DLCI from the Linux side. We issue SABM messages | ||
1442 | * to the modem which should then reply with a UA, at which point we | ||
1443 | * will move into open state. Opening is done asynchronously with retry | ||
1444 | * running off timers and the responses. | ||
1445 | */ | ||
1446 | |||
1447 | static void gsm_dlci_begin_open(struct gsm_dlci *dlci) | ||
1448 | { | ||
1449 | struct gsm_mux *gsm = dlci->gsm; | ||
1450 | if (dlci->state == DLCI_OPEN || dlci->state == DLCI_OPENING) | ||
1451 | return; | ||
1452 | dlci->retries = gsm->n2; | ||
1453 | dlci->state = DLCI_OPENING; | ||
1454 | gsm_command(dlci->gsm, dlci->addr, SABM|PF); | ||
1455 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | ||
1456 | } | ||
1457 | |||
1458 | /** | ||
1459 | * gsm_dlci_begin_close - start channel open procedure | ||
1460 | * @dlci: DLCI to open | ||
1461 | * | ||
1462 | * Commence closing a DLCI from the Linux side. We issue DISC messages | ||
1463 | * to the modem which should then reply with a UA, at which point we | ||
1464 | * will move into closed state. Closing is done asynchronously with retry | ||
1465 | * off timers. We may also receive a DM reply from the other end which | ||
1466 | * indicates the channel was already closed. | ||
1467 | */ | ||
1468 | |||
1469 | static void gsm_dlci_begin_close(struct gsm_dlci *dlci) | ||
1470 | { | ||
1471 | struct gsm_mux *gsm = dlci->gsm; | ||
1472 | if (dlci->state == DLCI_CLOSED || dlci->state == DLCI_CLOSING) | ||
1473 | return; | ||
1474 | dlci->retries = gsm->n2; | ||
1475 | dlci->state = DLCI_CLOSING; | ||
1476 | gsm_command(dlci->gsm, dlci->addr, DISC|PF); | ||
1477 | mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); | ||
1478 | } | ||
1479 | |||
1480 | /** | ||
1481 | * gsm_dlci_data - data arrived | ||
1482 | * @dlci: channel | ||
1483 | * @data: block of bytes received | ||
1484 | * @len: length of received block | ||
1485 | * | ||
1486 | * A UI or UIH frame has arrived which contains data for a channel | ||
1487 | * other than the control channel. If the relevant virtual tty is | ||
1488 | * open we shovel the bits down it, if not we drop them. | ||
1489 | */ | ||
1490 | |||
1491 | static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int len) | ||
1492 | { | ||
1493 | /* krefs .. */ | ||
1494 | struct tty_port *port = &dlci->port; | ||
1495 | struct tty_struct *tty = tty_port_tty_get(port); | ||
1496 | unsigned int modem = 0; | ||
1497 | |||
1498 | if (debug & 16) | ||
1499 | printk("%d bytes for tty %p\n", len, tty); | ||
1500 | if (tty) { | ||
1501 | switch (dlci->adaption) { | ||
1502 | /* Unsupported types */ | ||
1503 | /* Packetised interruptible data */ | ||
1504 | case 4: | ||
1505 | break; | ||
1506 | /* Packetised uininterruptible voice/data */ | ||
1507 | case 3: | ||
1508 | break; | ||
1509 | /* Asynchronous serial with line state in each frame */ | ||
1510 | case 2: | ||
1511 | while (gsm_read_ea(&modem, *data++) == 0) { | ||
1512 | len--; | ||
1513 | if (len == 0) | ||
1514 | return; | ||
1515 | } | ||
1516 | gsm_process_modem(tty, dlci, modem); | ||
1517 | /* Line state will go via DLCI 0 controls only */ | ||
1518 | case 1: | ||
1519 | default: | ||
1520 | tty_insert_flip_string(tty, data, len); | ||
1521 | tty_flip_buffer_push(tty); | ||
1522 | } | ||
1523 | tty_kref_put(tty); | ||
1524 | } | ||
1525 | } | ||
1526 | |||
1527 | /** | ||
1528 | * gsm_dlci_control - data arrived on control channel | ||
1529 | * @dlci: channel | ||
1530 | * @data: block of bytes received | ||
1531 | * @len: length of received block | ||
1532 | * | ||
1533 | * A UI or UIH frame has arrived which contains data for DLCI 0 the | ||
1534 | * control channel. This should contain a command EA followed by | ||
1535 | * control data bytes. The command EA contains a command/response bit | ||
1536 | * and we divide up the work accordingly. | ||
1537 | */ | ||
1538 | |||
1539 | static void gsm_dlci_command(struct gsm_dlci *dlci, u8 *data, int len) | ||
1540 | { | ||
1541 | /* See what command is involved */ | ||
1542 | unsigned int command = 0; | ||
1543 | while (len-- > 0) { | ||
1544 | if (gsm_read_ea(&command, *data++) == 1) { | ||
1545 | int clen = *data++; | ||
1546 | len--; | ||
1547 | /* FIXME: this is properly an EA */ | ||
1548 | clen >>= 1; | ||
1549 | /* Malformed command ? */ | ||
1550 | if (clen > len) | ||
1551 | return; | ||
1552 | if (command & 1) | ||
1553 | gsm_control_message(dlci->gsm, command, | ||
1554 | data, clen); | ||
1555 | else | ||
1556 | gsm_control_response(dlci->gsm, command, | ||
1557 | data, clen); | ||
1558 | return; | ||
1559 | } | ||
1560 | } | ||
1561 | } | ||
1562 | |||
1563 | /* | ||
1564 | * Allocate/Free DLCI channels | ||
1565 | */ | ||
1566 | |||
1567 | /** | ||
1568 | * gsm_dlci_alloc - allocate a DLCI | ||
1569 | * @gsm: GSM mux | ||
1570 | * @addr: address of the DLCI | ||
1571 | * | ||
1572 | * Allocate and install a new DLCI object into the GSM mux. | ||
1573 | * | ||
1574 | * FIXME: review locking races | ||
1575 | */ | ||
1576 | |||
1577 | static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr) | ||
1578 | { | ||
1579 | struct gsm_dlci *dlci = kzalloc(sizeof(struct gsm_dlci), GFP_ATOMIC); | ||
1580 | if (dlci == NULL) | ||
1581 | return NULL; | ||
1582 | spin_lock_init(&dlci->lock); | ||
1583 | dlci->fifo = &dlci->_fifo; | ||
1584 | if (kfifo_alloc(&dlci->_fifo, 4096, GFP_KERNEL) < 0) { | ||
1585 | kfree(dlci); | ||
1586 | return NULL; | ||
1587 | } | ||
1588 | |||
1589 | skb_queue_head_init(&dlci->skb_list); | ||
1590 | init_timer(&dlci->t1); | ||
1591 | dlci->t1.function = gsm_dlci_t1; | ||
1592 | dlci->t1.data = (unsigned long)dlci; | ||
1593 | tty_port_init(&dlci->port); | ||
1594 | dlci->port.ops = &gsm_port_ops; | ||
1595 | dlci->gsm = gsm; | ||
1596 | dlci->addr = addr; | ||
1597 | dlci->adaption = gsm->adaption; | ||
1598 | dlci->state = DLCI_CLOSED; | ||
1599 | if (addr) | ||
1600 | dlci->data = gsm_dlci_data; | ||
1601 | else | ||
1602 | dlci->data = gsm_dlci_command; | ||
1603 | gsm->dlci[addr] = dlci; | ||
1604 | return dlci; | ||
1605 | } | ||
1606 | |||
1607 | /** | ||
1608 | * gsm_dlci_free - release DLCI | ||
1609 | * @dlci: DLCI to destroy | ||
1610 | * | ||
1611 | * Free up a DLCI. Currently to keep the lifetime rules sane we only | ||
1612 | * clean up DLCI objects when the MUX closes rather than as the port | ||
1613 | * is closed down on both the tty and mux levels. | ||
1614 | * | ||
1615 | * Can sleep. | ||
1616 | */ | ||
1617 | static void gsm_dlci_free(struct gsm_dlci *dlci) | ||
1618 | { | ||
1619 | struct tty_struct *tty = tty_port_tty_get(&dlci->port); | ||
1620 | if (tty) { | ||
1621 | tty_vhangup(tty); | ||
1622 | tty_kref_put(tty); | ||
1623 | } | ||
1624 | del_timer_sync(&dlci->t1); | ||
1625 | dlci->gsm->dlci[dlci->addr] = NULL; | ||
1626 | kfifo_free(dlci->fifo); | ||
1627 | kfree(dlci); | ||
1628 | } | ||
1629 | |||
1630 | |||
1631 | /* | ||
1632 | * LAPBish link layer logic | ||
1633 | */ | ||
1634 | |||
1635 | /** | ||
1636 | * gsm_queue - a GSM frame is ready to process | ||
1637 | * @gsm: pointer to our gsm mux | ||
1638 | * | ||
1639 | * At this point in time a frame has arrived and been demangled from | ||
1640 | * the line encoding. All the differences between the encodings have | ||
1641 | * been handled below us and the frame is unpacked into the structures. | ||
1642 | * The fcs holds the header FCS but any data FCS must be added here. | ||
1643 | */ | ||
1644 | |||
1645 | static void gsm_queue(struct gsm_mux *gsm) | ||
1646 | { | ||
1647 | struct gsm_dlci *dlci; | ||
1648 | u8 cr; | ||
1649 | int address; | ||
1650 | /* We have to sneak a look at the packet body to do the FCS. | ||
1651 | A somewhat layering violation in the spec */ | ||
1652 | |||
1653 | if ((gsm->control & ~PF) == UI) | ||
1654 | gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len); | ||
1655 | if (gsm->fcs != GOOD_FCS) { | ||
1656 | gsm->bad_fcs++; | ||
1657 | if (debug & 4) | ||
1658 | printk("BAD FCS %02x\n", gsm->fcs); | ||
1659 | return; | ||
1660 | } | ||
1661 | address = gsm->address >> 1; | ||
1662 | if (address >= NUM_DLCI) | ||
1663 | goto invalid; | ||
1664 | |||
1665 | cr = gsm->address & 1; /* C/R bit */ | ||
1666 | |||
1667 | gsm_print_packet("<--", address, cr, gsm->control, gsm->buf, gsm->len); | ||
1668 | |||
1669 | cr ^= 1 - gsm->initiator; /* Flip so 1 always means command */ | ||
1670 | dlci = gsm->dlci[address]; | ||
1671 | |||
1672 | switch (gsm->control) { | ||
1673 | case SABM|PF: | ||
1674 | if (cr == 0) | ||
1675 | goto invalid; | ||
1676 | if (dlci == NULL) | ||
1677 | dlci = gsm_dlci_alloc(gsm, address); | ||
1678 | if (dlci == NULL) | ||
1679 | return; | ||
1680 | if (dlci->dead) | ||
1681 | gsm_response(gsm, address, DM); | ||
1682 | else { | ||
1683 | gsm_response(gsm, address, UA); | ||
1684 | gsm_dlci_open(dlci); | ||
1685 | } | ||
1686 | break; | ||
1687 | case DISC|PF: | ||
1688 | if (cr == 0) | ||
1689 | goto invalid; | ||
1690 | if (dlci == NULL || dlci->state == DLCI_CLOSED) { | ||
1691 | gsm_response(gsm, address, DM); | ||
1692 | return; | ||
1693 | } | ||
1694 | /* Real close complete */ | ||
1695 | gsm_response(gsm, address, UA); | ||
1696 | gsm_dlci_close(dlci); | ||
1697 | break; | ||
1698 | case UA: | ||
1699 | case UA|PF: | ||
1700 | if (cr == 0 || dlci == NULL) | ||
1701 | break; | ||
1702 | switch (dlci->state) { | ||
1703 | case DLCI_CLOSING: | ||
1704 | gsm_dlci_close(dlci); | ||
1705 | break; | ||
1706 | case DLCI_OPENING: | ||
1707 | gsm_dlci_open(dlci); | ||
1708 | break; | ||
1709 | } | ||
1710 | break; | ||
1711 | case DM: /* DM can be valid unsolicited */ | ||
1712 | case DM|PF: | ||
1713 | if (cr) | ||
1714 | goto invalid; | ||
1715 | if (dlci == NULL) | ||
1716 | return; | ||
1717 | gsm_dlci_close(dlci); | ||
1718 | break; | ||
1719 | case UI: | ||
1720 | case UI|PF: | ||
1721 | case UIH: | ||
1722 | case UIH|PF: | ||
1723 | #if 0 | ||
1724 | if (cr) | ||
1725 | goto invalid; | ||
1726 | #endif | ||
1727 | if (dlci == NULL || dlci->state != DLCI_OPEN) { | ||
1728 | gsm_command(gsm, address, DM|PF); | ||
1729 | return; | ||
1730 | } | ||
1731 | dlci->data(dlci, gsm->buf, gsm->len); | ||
1732 | break; | ||
1733 | default: | ||
1734 | goto invalid; | ||
1735 | } | ||
1736 | return; | ||
1737 | invalid: | ||
1738 | gsm->malformed++; | ||
1739 | return; | ||
1740 | } | ||
1741 | |||
1742 | |||
1743 | /** | ||
1744 | * gsm0_receive - perform processing for non-transparency | ||
1745 | * @gsm: gsm data for this ldisc instance | ||
1746 | * @c: character | ||
1747 | * | ||
1748 | * Receive bytes in gsm mode 0 | ||
1749 | */ | ||
1750 | |||
1751 | static void gsm0_receive(struct gsm_mux *gsm, unsigned char c) | ||
1752 | { | ||
1753 | switch (gsm->state) { | ||
1754 | case GSM_SEARCH: /* SOF marker */ | ||
1755 | if (c == GSM0_SOF) { | ||
1756 | gsm->state = GSM_ADDRESS; | ||
1757 | gsm->address = 0; | ||
1758 | gsm->len = 0; | ||
1759 | gsm->fcs = INIT_FCS; | ||
1760 | } | ||
1761 | break; /* Address EA */ | ||
1762 | case GSM_ADDRESS: | ||
1763 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | ||
1764 | if (gsm_read_ea(&gsm->address, c)) | ||
1765 | gsm->state = GSM_CONTROL; | ||
1766 | break; | ||
1767 | case GSM_CONTROL: /* Control Byte */ | ||
1768 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | ||
1769 | gsm->control = c; | ||
1770 | gsm->state = GSM_LEN; | ||
1771 | break; | ||
1772 | case GSM_LEN: /* Length EA */ | ||
1773 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | ||
1774 | if (gsm_read_ea(&gsm->len, c)) { | ||
1775 | if (gsm->len > gsm->mru) { | ||
1776 | gsm->bad_size++; | ||
1777 | gsm->state = GSM_SEARCH; | ||
1778 | break; | ||
1779 | } | ||
1780 | gsm->count = 0; | ||
1781 | gsm->state = GSM_DATA; | ||
1782 | } | ||
1783 | break; | ||
1784 | case GSM_DATA: /* Data */ | ||
1785 | gsm->buf[gsm->count++] = c; | ||
1786 | if (gsm->count == gsm->len) | ||
1787 | gsm->state = GSM_FCS; | ||
1788 | break; | ||
1789 | case GSM_FCS: /* FCS follows the packet */ | ||
1790 | gsm->fcs = c; | ||
1791 | gsm_queue(gsm); | ||
1792 | /* And then back for the next frame */ | ||
1793 | gsm->state = GSM_SEARCH; | ||
1794 | break; | ||
1795 | } | ||
1796 | } | ||
1797 | |||
1798 | /** | ||
1799 | * gsm0_receive - perform processing for non-transparency | ||
1800 | * @gsm: gsm data for this ldisc instance | ||
1801 | * @c: character | ||
1802 | * | ||
1803 | * Receive bytes in mode 1 (Advanced option) | ||
1804 | */ | ||
1805 | |||
1806 | static void gsm1_receive(struct gsm_mux *gsm, unsigned char c) | ||
1807 | { | ||
1808 | if (c == GSM1_SOF) { | ||
1809 | /* EOF is only valid in frame if we have got to the data state | ||
1810 | and received at least one byte (the FCS) */ | ||
1811 | if (gsm->state == GSM_DATA && gsm->count) { | ||
1812 | /* Extract the FCS */ | ||
1813 | gsm->count--; | ||
1814 | gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->buf[gsm->count]); | ||
1815 | gsm->len = gsm->count; | ||
1816 | gsm_queue(gsm); | ||
1817 | gsm->state = GSM_START; | ||
1818 | return; | ||
1819 | } | ||
1820 | /* Any partial frame was a runt so go back to start */ | ||
1821 | if (gsm->state != GSM_START) { | ||
1822 | gsm->malformed++; | ||
1823 | gsm->state = GSM_START; | ||
1824 | } | ||
1825 | /* A SOF in GSM_START means we are still reading idling or | ||
1826 | framing bytes */ | ||
1827 | return; | ||
1828 | } | ||
1829 | |||
1830 | if (c == GSM1_ESCAPE) { | ||
1831 | gsm->escape = 1; | ||
1832 | return; | ||
1833 | } | ||
1834 | |||
1835 | /* Only an unescaped SOF gets us out of GSM search */ | ||
1836 | if (gsm->state == GSM_SEARCH) | ||
1837 | return; | ||
1838 | |||
1839 | if (gsm->escape) { | ||
1840 | c ^= GSM1_ESCAPE_BITS; | ||
1841 | gsm->escape = 0; | ||
1842 | } | ||
1843 | switch (gsm->state) { | ||
1844 | case GSM_START: /* First byte after SOF */ | ||
1845 | gsm->address = 0; | ||
1846 | gsm->state = GSM_ADDRESS; | ||
1847 | gsm->fcs = INIT_FCS; | ||
1848 | /* Drop through */ | ||
1849 | case GSM_ADDRESS: /* Address continuation */ | ||
1850 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | ||
1851 | if (gsm_read_ea(&gsm->address, c)) | ||
1852 | gsm->state = GSM_CONTROL; | ||
1853 | break; | ||
1854 | case GSM_CONTROL: /* Control Byte */ | ||
1855 | gsm->fcs = gsm_fcs_add(gsm->fcs, c); | ||
1856 | gsm->control = c; | ||
1857 | gsm->count = 0; | ||
1858 | gsm->state = GSM_DATA; | ||
1859 | break; | ||
1860 | case GSM_DATA: /* Data */ | ||
1861 | if (gsm->count > gsm->mru ) { /* Allow one for the FCS */ | ||
1862 | gsm->state = GSM_OVERRUN; | ||
1863 | gsm->bad_size++; | ||
1864 | } else | ||
1865 | gsm->buf[gsm->count++] = c; | ||
1866 | break; | ||
1867 | case GSM_OVERRUN: /* Over-long - eg a dropped SOF */ | ||
1868 | break; | ||
1869 | } | ||
1870 | } | ||
1871 | |||
1872 | /** | ||
1873 | * gsm_error - handle tty error | ||
1874 | * @gsm: ldisc data | ||
1875 | * @data: byte received (may be invalid) | ||
1876 | * @flag: error received | ||
1877 | * | ||
1878 | * Handle an error in the receipt of data for a frame. Currently we just | ||
1879 | * go back to hunting for a SOF. | ||
1880 | * | ||
1881 | * FIXME: better diagnostics ? | ||
1882 | */ | ||
1883 | |||
1884 | static void gsm_error(struct gsm_mux *gsm, | ||
1885 | unsigned char data, unsigned char flag) | ||
1886 | { | ||
1887 | gsm->state = GSM_SEARCH; | ||
1888 | gsm->io_error++; | ||
1889 | } | ||
1890 | |||
1891 | /** | ||
1892 | * gsm_cleanup_mux - generic GSM protocol cleanup | ||
1893 | * @gsm: our mux | ||
1894 | * | ||
1895 | * Clean up the bits of the mux which are the same for all framing | ||
1896 | * protocols. Remove the mux from the mux table, stop all the timers | ||
1897 | * and then shut down each device hanging up the channels as we go. | ||
1898 | */ | ||
1899 | |||
1900 | void gsm_cleanup_mux(struct gsm_mux *gsm) | ||
1901 | { | ||
1902 | int i; | ||
1903 | struct gsm_dlci *dlci = gsm->dlci[0]; | ||
1904 | struct gsm_msg *txq; | ||
1905 | |||
1906 | gsm->dead = 1; | ||
1907 | |||
1908 | spin_lock(&gsm_mux_lock); | ||
1909 | for (i = 0; i < MAX_MUX; i++) { | ||
1910 | if (gsm_mux[i] == gsm) { | ||
1911 | gsm_mux[i] = NULL; | ||
1912 | break; | ||
1913 | } | ||
1914 | } | ||
1915 | spin_unlock(&gsm_mux_lock); | ||
1916 | WARN_ON(i == MAX_MUX); | ||
1917 | |||
1918 | del_timer_sync(&gsm->t2_timer); | ||
1919 | /* Now we are sure T2 has stopped */ | ||
1920 | if (dlci) { | ||
1921 | dlci->dead = 1; | ||
1922 | gsm_dlci_begin_close(dlci); | ||
1923 | wait_event_interruptible(gsm->event, | ||
1924 | dlci->state == DLCI_CLOSED); | ||
1925 | } | ||
1926 | /* Free up any link layer users */ | ||
1927 | for (i = 0; i < NUM_DLCI; i++) | ||
1928 | if (gsm->dlci[i]) | ||
1929 | gsm_dlci_free(gsm->dlci[i]); | ||
1930 | /* Now wipe the queues */ | ||
1931 | for (txq = gsm->tx_head; txq != NULL; txq = gsm->tx_head) { | ||
1932 | gsm->tx_head = txq->next; | ||
1933 | kfree(txq); | ||
1934 | } | ||
1935 | gsm->tx_tail = NULL; | ||
1936 | } | ||
1937 | EXPORT_SYMBOL_GPL(gsm_cleanup_mux); | ||
1938 | |||
1939 | /** | ||
1940 | * gsm_activate_mux - generic GSM setup | ||
1941 | * @gsm: our mux | ||
1942 | * | ||
1943 | * Set up the bits of the mux which are the same for all framing | ||
1944 | * protocols. Add the mux to the mux table so it can be opened and | ||
1945 | * finally kick off connecting to DLCI 0 on the modem. | ||
1946 | */ | ||
1947 | |||
1948 | int gsm_activate_mux(struct gsm_mux *gsm) | ||
1949 | { | ||
1950 | struct gsm_dlci *dlci; | ||
1951 | int i = 0; | ||
1952 | |||
1953 | init_timer(&gsm->t2_timer); | ||
1954 | gsm->t2_timer.function = gsm_control_retransmit; | ||
1955 | gsm->t2_timer.data = (unsigned long)gsm; | ||
1956 | init_waitqueue_head(&gsm->event); | ||
1957 | spin_lock_init(&gsm->control_lock); | ||
1958 | spin_lock_init(&gsm->tx_lock); | ||
1959 | |||
1960 | if (gsm->encoding == 0) | ||
1961 | gsm->receive = gsm0_receive; | ||
1962 | else | ||
1963 | gsm->receive = gsm1_receive; | ||
1964 | gsm->error = gsm_error; | ||
1965 | |||
1966 | spin_lock(&gsm_mux_lock); | ||
1967 | for (i = 0; i < MAX_MUX; i++) { | ||
1968 | if (gsm_mux[i] == NULL) { | ||
1969 | gsm_mux[i] = gsm; | ||
1970 | break; | ||
1971 | } | ||
1972 | } | ||
1973 | spin_unlock(&gsm_mux_lock); | ||
1974 | if (i == MAX_MUX) | ||
1975 | return -EBUSY; | ||
1976 | |||
1977 | dlci = gsm_dlci_alloc(gsm, 0); | ||
1978 | if (dlci == NULL) | ||
1979 | return -ENOMEM; | ||
1980 | gsm->dead = 0; /* Tty opens are now permissible */ | ||
1981 | return 0; | ||
1982 | } | ||
1983 | EXPORT_SYMBOL_GPL(gsm_activate_mux); | ||
1984 | |||
1985 | /** | ||
1986 | * gsm_free_mux - free up a mux | ||
1987 | * @mux: mux to free | ||
1988 | * | ||
1989 | * Dispose of allocated resources for a dead mux. No refcounting | ||
1990 | * at present so the mux must be truely dead. | ||
1991 | */ | ||
1992 | void gsm_free_mux(struct gsm_mux *gsm) | ||
1993 | { | ||
1994 | kfree(gsm->txframe); | ||
1995 | kfree(gsm->buf); | ||
1996 | kfree(gsm); | ||
1997 | } | ||
1998 | EXPORT_SYMBOL_GPL(gsm_free_mux); | ||
1999 | |||
2000 | /** | ||
2001 | * gsm_alloc_mux - allocate a mux | ||
2002 | * | ||
2003 | * Creates a new mux ready for activation. | ||
2004 | */ | ||
2005 | |||
2006 | struct gsm_mux *gsm_alloc_mux(void) | ||
2007 | { | ||
2008 | struct gsm_mux *gsm = kzalloc(sizeof(struct gsm_mux), GFP_KERNEL); | ||
2009 | if (gsm == NULL) | ||
2010 | return NULL; | ||
2011 | gsm->buf = kmalloc(MAX_MRU + 1, GFP_KERNEL); | ||
2012 | if (gsm->buf == NULL) { | ||
2013 | kfree(gsm); | ||
2014 | return NULL; | ||
2015 | } | ||
2016 | gsm->txframe = kmalloc(2 * MAX_MRU + 2, GFP_KERNEL); | ||
2017 | if (gsm->txframe == NULL) { | ||
2018 | kfree(gsm->buf); | ||
2019 | kfree(gsm); | ||
2020 | return NULL; | ||
2021 | } | ||
2022 | spin_lock_init(&gsm->lock); | ||
2023 | |||
2024 | gsm->t1 = T1; | ||
2025 | gsm->t2 = T2; | ||
2026 | gsm->n2 = N2; | ||
2027 | gsm->ftype = UIH; | ||
2028 | gsm->initiator = 0; | ||
2029 | gsm->adaption = 1; | ||
2030 | gsm->encoding = 1; | ||
2031 | gsm->mru = 64; /* Default to encoding 1 so these should be 64 */ | ||
2032 | gsm->mtu = 64; | ||
2033 | gsm->dead = 1; /* Avoid early tty opens */ | ||
2034 | |||
2035 | return gsm; | ||
2036 | } | ||
2037 | EXPORT_SYMBOL_GPL(gsm_alloc_mux); | ||
2038 | |||
2039 | |||
2040 | |||
2041 | |||
2042 | /** | ||
2043 | * gsmld_output - write to link | ||
2044 | * @gsm: our mux | ||
2045 | * @data: bytes to output | ||
2046 | * @len: size | ||
2047 | * | ||
2048 | * Write a block of data from the GSM mux to the data channel. This | ||
2049 | * will eventually be serialized from above but at the moment isn't. | ||
2050 | */ | ||
2051 | |||
2052 | static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len) | ||
2053 | { | ||
2054 | if (tty_write_room(gsm->tty) < len) { | ||
2055 | set_bit(TTY_DO_WRITE_WAKEUP, &gsm->tty->flags); | ||
2056 | return -ENOSPC; | ||
2057 | } | ||
2058 | if (debug & 4) { | ||
2059 | printk("-->%d bytes out\n", len); | ||
2060 | hex_packet(data, len); | ||
2061 | } | ||
2062 | gsm->tty->ops->write(gsm->tty, data, len); | ||
2063 | return len; | ||
2064 | } | ||
2065 | |||
2066 | /** | ||
2067 | * gsmld_attach_gsm - mode set up | ||
2068 | * @tty: our tty structure | ||
2069 | * @gsm: our mux | ||
2070 | * | ||
2071 | * Set up the MUX for basic mode and commence connecting to the | ||
2072 | * modem. Currently called from the line discipline set up but | ||
2073 | * will need moving to an ioctl path. | ||
2074 | */ | ||
2075 | |||
2076 | static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) | ||
2077 | { | ||
2078 | int ret; | ||
2079 | |||
2080 | gsm->tty = tty_kref_get(tty); | ||
2081 | gsm->output = gsmld_output; | ||
2082 | ret = gsm_activate_mux(gsm); | ||
2083 | if (ret != 0) | ||
2084 | tty_kref_put(gsm->tty); | ||
2085 | return ret; | ||
2086 | } | ||
2087 | |||
2088 | |||
2089 | /** | ||
2090 | * gsmld_detach_gsm - stop doing 0710 mux | ||
2091 | * @tty: tty atttached to the mux | ||
2092 | * @gsm: mux | ||
2093 | * | ||
2094 | * Shutdown and then clean up the resources used by the line discipline | ||
2095 | */ | ||
2096 | |||
2097 | static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) | ||
2098 | { | ||
2099 | WARN_ON(tty != gsm->tty); | ||
2100 | gsm_cleanup_mux(gsm); | ||
2101 | tty_kref_put(gsm->tty); | ||
2102 | gsm->tty = NULL; | ||
2103 | } | ||
2104 | |||
2105 | static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, | ||
2106 | char *fp, int count) | ||
2107 | { | ||
2108 | struct gsm_mux *gsm = tty->disc_data; | ||
2109 | const unsigned char *dp; | ||
2110 | char *f; | ||
2111 | int i; | ||
2112 | char buf[64]; | ||
2113 | char flags; | ||
2114 | |||
2115 | if (debug & 4) { | ||
2116 | printk("Inbytes %dd\n", count); | ||
2117 | hex_packet(cp, count); | ||
2118 | } | ||
2119 | |||
2120 | for (i = count, dp = cp, f = fp; i; i--, dp++) { | ||
2121 | flags = *f++; | ||
2122 | switch (flags) { | ||
2123 | case TTY_NORMAL: | ||
2124 | gsm->receive(gsm, *dp); | ||
2125 | break; | ||
2126 | case TTY_OVERRUN: | ||
2127 | case TTY_BREAK: | ||
2128 | case TTY_PARITY: | ||
2129 | case TTY_FRAME: | ||
2130 | gsm->error(gsm, *dp, flags); | ||
2131 | break; | ||
2132 | default: | ||
2133 | printk(KERN_ERR "%s: unknown flag %d\n", | ||
2134 | tty_name(tty, buf), flags); | ||
2135 | break; | ||
2136 | } | ||
2137 | } | ||
2138 | /* FASYNC if needed ? */ | ||
2139 | /* If clogged call tty_throttle(tty); */ | ||
2140 | } | ||
2141 | |||
2142 | /** | ||
2143 | * gsmld_chars_in_buffer - report available bytes | ||
2144 | * @tty: tty device | ||
2145 | * | ||
2146 | * Report the number of characters buffered to be delivered to user | ||
2147 | * at this instant in time. | ||
2148 | * | ||
2149 | * Locking: gsm lock | ||
2150 | */ | ||
2151 | |||
2152 | static ssize_t gsmld_chars_in_buffer(struct tty_struct *tty) | ||
2153 | { | ||
2154 | return 0; | ||
2155 | } | ||
2156 | |||
2157 | /** | ||
2158 | * gsmld_flush_buffer - clean input queue | ||
2159 | * @tty: terminal device | ||
2160 | * | ||
2161 | * Flush the input buffer. Called when the line discipline is | ||
2162 | * being closed, when the tty layer wants the buffer flushed (eg | ||
2163 | * at hangup). | ||
2164 | */ | ||
2165 | |||
2166 | static void gsmld_flush_buffer(struct tty_struct *tty) | ||
2167 | { | ||
2168 | } | ||
2169 | |||
2170 | /** | ||
2171 | * gsmld_close - close the ldisc for this tty | ||
2172 | * @tty: device | ||
2173 | * | ||
2174 | * Called from the terminal layer when this line discipline is | ||
2175 | * being shut down, either because of a close or becsuse of a | ||
2176 | * discipline change. The function will not be called while other | ||
2177 | * ldisc methods are in progress. | ||
2178 | */ | ||
2179 | |||
2180 | static void gsmld_close(struct tty_struct *tty) | ||
2181 | { | ||
2182 | struct gsm_mux *gsm = tty->disc_data; | ||
2183 | |||
2184 | gsmld_detach_gsm(tty, gsm); | ||
2185 | |||
2186 | gsmld_flush_buffer(tty); | ||
2187 | /* Do other clean up here */ | ||
2188 | gsm_free_mux(gsm); | ||
2189 | } | ||
2190 | |||
2191 | /** | ||
2192 | * gsmld_open - open an ldisc | ||
2193 | * @tty: terminal to open | ||
2194 | * | ||
2195 | * Called when this line discipline is being attached to the | ||
2196 | * terminal device. Can sleep. Called serialized so that no | ||
2197 | * other events will occur in parallel. No further open will occur | ||
2198 | * until a close. | ||
2199 | */ | ||
2200 | |||
2201 | static int gsmld_open(struct tty_struct *tty) | ||
2202 | { | ||
2203 | struct gsm_mux *gsm; | ||
2204 | |||
2205 | if (tty->ops->write == NULL) | ||
2206 | return -EINVAL; | ||
2207 | |||
2208 | /* Attach our ldisc data */ | ||
2209 | gsm = gsm_alloc_mux(); | ||
2210 | if (gsm == NULL) | ||
2211 | return -ENOMEM; | ||
2212 | |||
2213 | tty->disc_data = gsm; | ||
2214 | tty->receive_room = 65536; | ||
2215 | |||
2216 | /* Attach the initial passive connection */ | ||
2217 | gsm->encoding = 1; | ||
2218 | return gsmld_attach_gsm(tty, gsm); | ||
2219 | } | ||
2220 | |||
2221 | /** | ||
2222 | * gsmld_write_wakeup - asynchronous I/O notifier | ||
2223 | * @tty: tty device | ||
2224 | * | ||
2225 | * Required for the ptys, serial driver etc. since processes | ||
2226 | * that attach themselves to the master and rely on ASYNC | ||
2227 | * IO must be woken up | ||
2228 | */ | ||
2229 | |||
2230 | static void gsmld_write_wakeup(struct tty_struct *tty) | ||
2231 | { | ||
2232 | struct gsm_mux *gsm = tty->disc_data; | ||
2233 | |||
2234 | /* Queue poll */ | ||
2235 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); | ||
2236 | gsm_data_kick(gsm); | ||
2237 | if (gsm->tx_bytes < TX_THRESH_LO) | ||
2238 | gsm_dlci_data_sweep(gsm); | ||
2239 | } | ||
2240 | |||
2241 | /** | ||
2242 | * gsmld_read - read function for tty | ||
2243 | * @tty: tty device | ||
2244 | * @file: file object | ||
2245 | * @buf: userspace buffer pointer | ||
2246 | * @nr: size of I/O | ||
2247 | * | ||
2248 | * Perform reads for the line discipline. We are guaranteed that the | ||
2249 | * line discipline will not be closed under us but we may get multiple | ||
2250 | * parallel readers and must handle this ourselves. We may also get | ||
2251 | * a hangup. Always called in user context, may sleep. | ||
2252 | * | ||
2253 | * This code must be sure never to sleep through a hangup. | ||
2254 | */ | ||
2255 | |||
2256 | static ssize_t gsmld_read(struct tty_struct *tty, struct file *file, | ||
2257 | unsigned char __user *buf, size_t nr) | ||
2258 | { | ||
2259 | return -EOPNOTSUPP; | ||
2260 | } | ||
2261 | |||
2262 | /** | ||
2263 | * gsmld_write - write function for tty | ||
2264 | * @tty: tty device | ||
2265 | * @file: file object | ||
2266 | * @buf: userspace buffer pointer | ||
2267 | * @nr: size of I/O | ||
2268 | * | ||
2269 | * Called when the owner of the device wants to send a frame | ||
2270 | * itself (or some other control data). The data is transferred | ||
2271 | * as-is and must be properly framed and checksummed as appropriate | ||
2272 | * by userspace. Frames are either sent whole or not at all as this | ||
2273 | * avoids pain user side. | ||
2274 | */ | ||
2275 | |||
2276 | static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, | ||
2277 | const unsigned char *buf, size_t nr) | ||
2278 | { | ||
2279 | int space = tty_write_room(tty); | ||
2280 | if (space >= nr) | ||
2281 | return tty->ops->write(tty, buf, nr); | ||
2282 | set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); | ||
2283 | return -ENOBUFS; | ||
2284 | } | ||
2285 | |||
2286 | /** | ||
2287 | * gsmld_poll - poll method for N_GSM0710 | ||
2288 | * @tty: terminal device | ||
2289 | * @file: file accessing it | ||
2290 | * @wait: poll table | ||
2291 | * | ||
2292 | * Called when the line discipline is asked to poll() for data or | ||
2293 | * for special events. This code is not serialized with respect to | ||
2294 | * other events save open/close. | ||
2295 | * | ||
2296 | * This code must be sure never to sleep through a hangup. | ||
2297 | * Called without the kernel lock held - fine | ||
2298 | */ | ||
2299 | |||
2300 | static unsigned int gsmld_poll(struct tty_struct *tty, struct file *file, | ||
2301 | poll_table *wait) | ||
2302 | { | ||
2303 | unsigned int mask = 0; | ||
2304 | struct gsm_mux *gsm = tty->disc_data; | ||
2305 | |||
2306 | poll_wait(file, &tty->read_wait, wait); | ||
2307 | poll_wait(file, &tty->write_wait, wait); | ||
2308 | if (tty_hung_up_p(file)) | ||
2309 | mask |= POLLHUP; | ||
2310 | if (!tty_is_writelocked(tty) && tty_write_room(tty) > 0) | ||
2311 | mask |= POLLOUT | POLLWRNORM; | ||
2312 | if (gsm->dead) | ||
2313 | mask |= POLLHUP; | ||
2314 | return mask; | ||
2315 | } | ||
2316 | |||
2317 | static int gsmld_config(struct tty_struct *tty, struct gsm_mux *gsm, | ||
2318 | struct gsm_config *c) | ||
2319 | { | ||
2320 | int need_close = 0; | ||
2321 | int need_restart = 0; | ||
2322 | |||
2323 | /* Stuff we don't support yet - UI or I frame transport, windowing */ | ||
2324 | if ((c->adaption !=1 && c->adaption != 2) || c->k) | ||
2325 | return -EOPNOTSUPP; | ||
2326 | /* Check the MRU/MTU range looks sane */ | ||
2327 | if (c->mru > MAX_MRU || c->mtu > MAX_MTU || c->mru < 8 || c->mtu < 8) | ||
2328 | return -EINVAL; | ||
2329 | if (c->n2 < 3) | ||
2330 | return -EINVAL; | ||
2331 | if (c->encapsulation > 1) /* Basic, advanced, no I */ | ||
2332 | return -EINVAL; | ||
2333 | if (c->initiator > 1) | ||
2334 | return -EINVAL; | ||
2335 | if (c->i == 0 || c->i > 2) /* UIH and UI only */ | ||
2336 | return -EINVAL; | ||
2337 | /* | ||
2338 | * See what is needed for reconfiguration | ||
2339 | */ | ||
2340 | |||
2341 | /* Timing fields */ | ||
2342 | if (c->t1 != 0 && c->t1 != gsm->t1) | ||
2343 | need_restart = 1; | ||
2344 | if (c->t2 != 0 && c->t2 != gsm->t2) | ||
2345 | need_restart = 1; | ||
2346 | if (c->encapsulation != gsm->encoding) | ||
2347 | need_restart = 1; | ||
2348 | if (c->adaption != gsm->adaption) | ||
2349 | need_restart = 1; | ||
2350 | /* Requires care */ | ||
2351 | if (c->initiator != gsm->initiator) | ||
2352 | need_close = 1; | ||
2353 | if (c->mru != gsm->mru) | ||
2354 | need_restart = 1; | ||
2355 | if (c->mtu != gsm->mtu) | ||
2356 | need_restart = 1; | ||
2357 | |||
2358 | /* | ||
2359 | * Close down what is needed, restart and initiate the new | ||
2360 | * configuration | ||
2361 | */ | ||
2362 | |||
2363 | if (need_close || need_restart) { | ||
2364 | gsm_dlci_begin_close(gsm->dlci[0]); | ||
2365 | /* This will timeout if the link is down due to N2 expiring */ | ||
2366 | wait_event_interruptible(gsm->event, | ||
2367 | gsm->dlci[0]->state == DLCI_CLOSED); | ||
2368 | if (signal_pending(current)) | ||
2369 | return -EINTR; | ||
2370 | } | ||
2371 | if (need_restart) | ||
2372 | gsm_cleanup_mux(gsm); | ||
2373 | |||
2374 | gsm->initiator = c->initiator; | ||
2375 | gsm->mru = c->mru; | ||
2376 | gsm->encoding = c->encapsulation; | ||
2377 | gsm->adaption = c->adaption; | ||
2378 | |||
2379 | if (c->i == 1) | ||
2380 | gsm->ftype = UIH; | ||
2381 | else if (c->i == 2) | ||
2382 | gsm->ftype = UI; | ||
2383 | |||
2384 | if (c->t1) | ||
2385 | gsm->t1 = c->t1; | ||
2386 | if (c->t2) | ||
2387 | gsm->t2 = c->t2; | ||
2388 | |||
2389 | /* FIXME: We need to separate activation/deactivation from adding | ||
2390 | and removing from the mux array */ | ||
2391 | if (need_restart) | ||
2392 | gsm_activate_mux(gsm); | ||
2393 | if (gsm->initiator && need_close) | ||
2394 | gsm_dlci_begin_open(gsm->dlci[0]); | ||
2395 | return 0; | ||
2396 | } | ||
2397 | |||
2398 | static int gsmld_ioctl(struct tty_struct *tty, struct file *file, | ||
2399 | unsigned int cmd, unsigned long arg) | ||
2400 | { | ||
2401 | struct gsm_config c; | ||
2402 | struct gsm_mux *gsm = tty->disc_data; | ||
2403 | |||
2404 | switch (cmd) { | ||
2405 | case GSMIOC_GETCONF: | ||
2406 | memset(&c, 0, sizeof(c)); | ||
2407 | c.adaption = gsm->adaption; | ||
2408 | c.encapsulation = gsm->encoding; | ||
2409 | c.initiator = gsm->initiator; | ||
2410 | c.t1 = gsm->t1; | ||
2411 | c.t2 = gsm->t2; | ||
2412 | c.t3 = 0; /* Not supported */ | ||
2413 | c.n2 = gsm->n2; | ||
2414 | if (gsm->ftype == UIH) | ||
2415 | c.i = 1; | ||
2416 | else | ||
2417 | c.i = 2; | ||
2418 | printk("Ftype %d i %d\n", gsm->ftype, c.i); | ||
2419 | c.mru = gsm->mru; | ||
2420 | c.mtu = gsm->mtu; | ||
2421 | c.k = 0; | ||
2422 | if (copy_to_user((void *)arg, &c, sizeof(c))) | ||
2423 | return -EFAULT; | ||
2424 | return 0; | ||
2425 | case GSMIOC_SETCONF: | ||
2426 | if (copy_from_user(&c, (void *)arg, sizeof(c))) | ||
2427 | return -EFAULT; | ||
2428 | return gsmld_config(tty, gsm, &c); | ||
2429 | default: | ||
2430 | return n_tty_ioctl_helper(tty, file, cmd, arg); | ||
2431 | } | ||
2432 | } | ||
2433 | |||
2434 | |||
2435 | /* Line discipline for real tty */ | ||
2436 | struct tty_ldisc_ops tty_ldisc_packet = { | ||
2437 | .owner = THIS_MODULE, | ||
2438 | .magic = TTY_LDISC_MAGIC, | ||
2439 | .name = "n_gsm", | ||
2440 | .open = gsmld_open, | ||
2441 | .close = gsmld_close, | ||
2442 | .flush_buffer = gsmld_flush_buffer, | ||
2443 | .chars_in_buffer = gsmld_chars_in_buffer, | ||
2444 | .read = gsmld_read, | ||
2445 | .write = gsmld_write, | ||
2446 | .ioctl = gsmld_ioctl, | ||
2447 | .poll = gsmld_poll, | ||
2448 | .receive_buf = gsmld_receive_buf, | ||
2449 | .write_wakeup = gsmld_write_wakeup | ||
2450 | }; | ||
2451 | |||
2452 | /* | ||
2453 | * Virtual tty side | ||
2454 | */ | ||
2455 | |||
2456 | #define TX_SIZE 512 | ||
2457 | |||
2458 | static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk) | ||
2459 | { | ||
2460 | u8 modembits[5]; | ||
2461 | struct gsm_control *ctrl; | ||
2462 | int len = 2; | ||
2463 | |||
2464 | if (brk) | ||
2465 | len++; | ||
2466 | |||
2467 | modembits[0] = len << 1 | EA; /* Data bytes */ | ||
2468 | modembits[1] = dlci->addr << 2 | 3; /* DLCI, EA, 1 */ | ||
2469 | modembits[2] = gsm_encode_modem(dlci) << 1 | EA; | ||
2470 | if (brk) | ||
2471 | modembits[3] = brk << 4 | 2 | EA; /* Valid, EA */ | ||
2472 | ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len + 1); | ||
2473 | if (ctrl == NULL) | ||
2474 | return -ENOMEM; | ||
2475 | return gsm_control_wait(dlci->gsm, ctrl); | ||
2476 | } | ||
2477 | |||
2478 | static int gsm_carrier_raised(struct tty_port *port) | ||
2479 | { | ||
2480 | struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); | ||
2481 | /* Not yet open so no carrier info */ | ||
2482 | if (dlci->state != DLCI_OPEN) | ||
2483 | return 0; | ||
2484 | if (debug & 2) | ||
2485 | return 1; | ||
2486 | return dlci->modem_rx & TIOCM_CD; | ||
2487 | } | ||
2488 | |||
2489 | static void gsm_dtr_rts(struct tty_port *port, int onoff) | ||
2490 | { | ||
2491 | struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); | ||
2492 | unsigned int modem_tx = dlci->modem_tx; | ||
2493 | if (onoff) | ||
2494 | modem_tx |= TIOCM_DTR | TIOCM_RTS; | ||
2495 | else | ||
2496 | modem_tx &= ~(TIOCM_DTR | TIOCM_RTS); | ||
2497 | if (modem_tx != dlci->modem_tx) { | ||
2498 | dlci->modem_tx = modem_tx; | ||
2499 | gsmtty_modem_update(dlci, 0); | ||
2500 | } | ||
2501 | } | ||
2502 | |||
2503 | static const struct tty_port_operations gsm_port_ops = { | ||
2504 | .carrier_raised = gsm_carrier_raised, | ||
2505 | .dtr_rts = gsm_dtr_rts, | ||
2506 | }; | ||
2507 | |||
2508 | |||
2509 | static int gsmtty_open(struct tty_struct *tty, struct file *filp) | ||
2510 | { | ||
2511 | struct gsm_mux *gsm; | ||
2512 | struct gsm_dlci *dlci; | ||
2513 | struct tty_port *port; | ||
2514 | unsigned int line = tty->index; | ||
2515 | unsigned int mux = line >> 6; | ||
2516 | |||
2517 | line = line & 0x3F; | ||
2518 | |||
2519 | if (mux >= MAX_MUX) | ||
2520 | return -ENXIO; | ||
2521 | /* FIXME: we need to lock gsm_mux for lifetimes of ttys eventually */ | ||
2522 | if (gsm_mux[mux] == NULL) | ||
2523 | return -EUNATCH; | ||
2524 | if (line == 0 || line > 61) /* 62/63 reserved */ | ||
2525 | return -ECHRNG; | ||
2526 | gsm = gsm_mux[mux]; | ||
2527 | if (gsm->dead) | ||
2528 | return -EL2HLT; | ||
2529 | dlci = gsm->dlci[line]; | ||
2530 | if (dlci == NULL) | ||
2531 | dlci = gsm_dlci_alloc(gsm, line); | ||
2532 | if (dlci == NULL) | ||
2533 | return -ENOMEM; | ||
2534 | port = &dlci->port; | ||
2535 | port->count++; | ||
2536 | tty->driver_data = dlci; | ||
2537 | tty_port_tty_set(port, tty); | ||
2538 | |||
2539 | dlci->modem_rx = 0; | ||
2540 | /* We could in theory open and close before we wait - eg if we get | ||
2541 | a DM straight back. This is ok as that will have caused a hangup */ | ||
2542 | set_bit(ASYNCB_INITIALIZED, &port->flags); | ||
2543 | /* Start sending off SABM messages */ | ||
2544 | gsm_dlci_begin_open(dlci); | ||
2545 | /* And wait for virtual carrier */ | ||
2546 | return tty_port_block_til_ready(port, tty, filp); | ||
2547 | } | ||
2548 | |||
2549 | static void gsmtty_close(struct tty_struct *tty, struct file *filp) | ||
2550 | { | ||
2551 | struct gsm_dlci *dlci = tty->driver_data; | ||
2552 | if (dlci == NULL) | ||
2553 | return; | ||
2554 | if (tty_port_close_start(&dlci->port, tty, filp) == 0) | ||
2555 | return; | ||
2556 | gsm_dlci_begin_close(dlci); | ||
2557 | tty_port_close_end(&dlci->port, tty); | ||
2558 | tty_port_tty_set(&dlci->port, NULL); | ||
2559 | } | ||
2560 | |||
2561 | static void gsmtty_hangup(struct tty_struct *tty) | ||
2562 | { | ||
2563 | struct gsm_dlci *dlci = tty->driver_data; | ||
2564 | tty_port_hangup(&dlci->port); | ||
2565 | gsm_dlci_begin_close(dlci); | ||
2566 | } | ||
2567 | |||
2568 | static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf, | ||
2569 | int len) | ||
2570 | { | ||
2571 | struct gsm_dlci *dlci = tty->driver_data; | ||
2572 | /* Stuff the bytes into the fifo queue */ | ||
2573 | int sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock); | ||
2574 | /* Need to kick the channel */ | ||
2575 | gsm_dlci_data_kick(dlci); | ||
2576 | return sent; | ||
2577 | } | ||
2578 | |||
2579 | static int gsmtty_write_room(struct tty_struct *tty) | ||
2580 | { | ||
2581 | struct gsm_dlci *dlci = tty->driver_data; | ||
2582 | return TX_SIZE - kfifo_len(dlci->fifo); | ||
2583 | } | ||
2584 | |||
2585 | static int gsmtty_chars_in_buffer(struct tty_struct *tty) | ||
2586 | { | ||
2587 | struct gsm_dlci *dlci = tty->driver_data; | ||
2588 | return kfifo_len(dlci->fifo); | ||
2589 | } | ||
2590 | |||
2591 | static void gsmtty_flush_buffer(struct tty_struct *tty) | ||
2592 | { | ||
2593 | struct gsm_dlci *dlci = tty->driver_data; | ||
2594 | /* Caution needed: If we implement reliable transport classes | ||
2595 | then the data being transmitted can't simply be junked once | ||
2596 | it has first hit the stack. Until then we can just blow it | ||
2597 | away */ | ||
2598 | kfifo_reset(dlci->fifo); | ||
2599 | /* Need to unhook this DLCI from the transmit queue logic */ | ||
2600 | } | ||
2601 | |||
2602 | static void gsmtty_wait_until_sent(struct tty_struct *tty, int timeout) | ||
2603 | { | ||
2604 | /* The FIFO handles the queue so the kernel will do the right | ||
2605 | thing waiting on chars_in_buffer before calling us. No work | ||
2606 | to do here */ | ||
2607 | } | ||
2608 | |||
2609 | static int gsmtty_tiocmget(struct tty_struct *tty, struct file *filp) | ||
2610 | { | ||
2611 | struct gsm_dlci *dlci = tty->driver_data; | ||
2612 | return dlci->modem_rx; | ||
2613 | } | ||
2614 | |||
2615 | static int gsmtty_tiocmset(struct tty_struct *tty, struct file *filp, | ||
2616 | unsigned int set, unsigned int clear) | ||
2617 | { | ||
2618 | struct gsm_dlci *dlci = tty->driver_data; | ||
2619 | unsigned int modem_tx = dlci->modem_tx; | ||
2620 | |||
2621 | modem_tx &= clear; | ||
2622 | modem_tx |= set; | ||
2623 | |||
2624 | if (modem_tx != dlci->modem_tx) { | ||
2625 | dlci->modem_tx = modem_tx; | ||
2626 | return gsmtty_modem_update(dlci, 0); | ||
2627 | } | ||
2628 | return 0; | ||
2629 | } | ||
2630 | |||
2631 | |||
2632 | static int gsmtty_ioctl(struct tty_struct *tty, struct file *filp, | ||
2633 | unsigned int cmd, unsigned long arg) | ||
2634 | { | ||
2635 | return -ENOIOCTLCMD; | ||
2636 | } | ||
2637 | |||
2638 | static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old) | ||
2639 | { | ||
2640 | /* For the moment its fixed. In actual fact the speed information | ||
2641 | for the virtual channel can be propogated in both directions by | ||
2642 | the RPN control message. This however rapidly gets nasty as we | ||
2643 | then have to remap modem signals each way according to whether | ||
2644 | our virtual cable is null modem etc .. */ | ||
2645 | tty_termios_copy_hw(tty->termios, old); | ||
2646 | } | ||
2647 | |||
2648 | static void gsmtty_throttle(struct tty_struct *tty) | ||
2649 | { | ||
2650 | struct gsm_dlci *dlci = tty->driver_data; | ||
2651 | if (tty->termios->c_cflag & CRTSCTS) | ||
2652 | dlci->modem_tx &= ~TIOCM_DTR; | ||
2653 | dlci->throttled = 1; | ||
2654 | /* Send an MSC with DTR cleared */ | ||
2655 | gsmtty_modem_update(dlci, 0); | ||
2656 | } | ||
2657 | |||
2658 | static void gsmtty_unthrottle(struct tty_struct *tty) | ||
2659 | { | ||
2660 | struct gsm_dlci *dlci = tty->driver_data; | ||
2661 | if (tty->termios->c_cflag & CRTSCTS) | ||
2662 | dlci->modem_tx |= TIOCM_DTR; | ||
2663 | dlci->throttled = 0; | ||
2664 | /* Send an MSC with DTR set */ | ||
2665 | gsmtty_modem_update(dlci, 0); | ||
2666 | } | ||
2667 | |||
2668 | static int gsmtty_break_ctl(struct tty_struct *tty, int state) | ||
2669 | { | ||
2670 | struct gsm_dlci *dlci = tty->driver_data; | ||
2671 | int encode = 0; /* Off */ | ||
2672 | |||
2673 | if (state == -1) /* "On indefinitely" - we can't encode this | ||
2674 | properly */ | ||
2675 | encode = 0x0F; | ||
2676 | else if (state > 0) { | ||
2677 | encode = state / 200; /* mS to encoding */ | ||
2678 | if (encode > 0x0F) | ||
2679 | encode = 0x0F; /* Best effort */ | ||
2680 | } | ||
2681 | return gsmtty_modem_update(dlci, encode); | ||
2682 | } | ||
2683 | |||
2684 | static struct tty_driver *gsm_tty_driver; | ||
2685 | |||
2686 | /* Virtual ttys for the demux */ | ||
2687 | static const struct tty_operations gsmtty_ops = { | ||
2688 | .open = gsmtty_open, | ||
2689 | .close = gsmtty_close, | ||
2690 | .write = gsmtty_write, | ||
2691 | .write_room = gsmtty_write_room, | ||
2692 | .chars_in_buffer = gsmtty_chars_in_buffer, | ||
2693 | .flush_buffer = gsmtty_flush_buffer, | ||
2694 | .ioctl = gsmtty_ioctl, | ||
2695 | .throttle = gsmtty_throttle, | ||
2696 | .unthrottle = gsmtty_unthrottle, | ||
2697 | .set_termios = gsmtty_set_termios, | ||
2698 | .hangup = gsmtty_hangup, | ||
2699 | .wait_until_sent = gsmtty_wait_until_sent, | ||
2700 | .tiocmget = gsmtty_tiocmget, | ||
2701 | .tiocmset = gsmtty_tiocmset, | ||
2702 | .break_ctl = gsmtty_break_ctl, | ||
2703 | }; | ||
2704 | |||
2705 | |||
2706 | |||
2707 | static int __init gsm_init(void) | ||
2708 | { | ||
2709 | /* Fill in our line protocol discipline, and register it */ | ||
2710 | int status = tty_register_ldisc(N_GSM0710, &tty_ldisc_packet); | ||
2711 | if (status != 0) { | ||
2712 | printk(KERN_ERR "n_gsm: can't register line discipline (err = %d)\n", status); | ||
2713 | return status; | ||
2714 | } | ||
2715 | |||
2716 | gsm_tty_driver = alloc_tty_driver(256); | ||
2717 | if (!gsm_tty_driver) { | ||
2718 | tty_unregister_ldisc(N_GSM0710); | ||
2719 | printk(KERN_ERR "gsm_init: tty allocation failed.\n"); | ||
2720 | return -EINVAL; | ||
2721 | } | ||
2722 | gsm_tty_driver->owner = THIS_MODULE; | ||
2723 | gsm_tty_driver->driver_name = "gsmtty"; | ||
2724 | gsm_tty_driver->name = "gsmtty"; | ||
2725 | gsm_tty_driver->major = 0; /* Dynamic */ | ||
2726 | gsm_tty_driver->minor_start = 0; | ||
2727 | gsm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL; | ||
2728 | gsm_tty_driver->subtype = SERIAL_TYPE_NORMAL; | ||
2729 | gsm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV | ||
2730 | | TTY_DRIVER_HARDWARE_BREAK; | ||
2731 | gsm_tty_driver->init_termios = tty_std_termios; | ||
2732 | /* Fixme */ | ||
2733 | gsm_tty_driver->init_termios.c_lflag &= ~ECHO; | ||
2734 | tty_set_operations(gsm_tty_driver, &gsmtty_ops); | ||
2735 | |||
2736 | spin_lock_init(&gsm_mux_lock); | ||
2737 | |||
2738 | if (tty_register_driver(gsm_tty_driver)) { | ||
2739 | put_tty_driver(gsm_tty_driver); | ||
2740 | tty_unregister_ldisc(N_GSM0710); | ||
2741 | printk(KERN_ERR "gsm_init: tty registration failed.\n"); | ||
2742 | return -EBUSY; | ||
2743 | } | ||
2744 | printk(KERN_INFO "gsm_init: loaded as %d,%d.\n", gsm_tty_driver->major, gsm_tty_driver->minor_start); | ||
2745 | return 0; | ||
2746 | } | ||
2747 | |||
2748 | static void __exit gsm_exit(void) | ||
2749 | { | ||
2750 | int status = tty_unregister_ldisc(N_GSM0710); | ||
2751 | if (status != 0) | ||
2752 | printk(KERN_ERR "n_gsm: can't unregister line discipline (err = %d)\n", status); | ||
2753 | tty_unregister_driver(gsm_tty_driver); | ||
2754 | put_tty_driver(gsm_tty_driver); | ||
2755 | printk(KERN_INFO "gsm_init: unloaded.\n"); | ||
2756 | } | ||
2757 | |||
2758 | module_init(gsm_init); | ||
2759 | module_exit(gsm_exit); | ||
2760 | |||
2761 | |||
2762 | MODULE_LICENSE("GPL"); | ||
2763 | MODULE_ALIAS_LDISC(N_GSM0710); | ||
diff --git a/include/linux/gsmmux.h b/include/linux/gsmmux.h new file mode 100644 index 000000000000..378de4195caf --- /dev/null +++ b/include/linux/gsmmux.h | |||
@@ -0,0 +1,25 @@ | |||
1 | #ifndef _LINUX_GSMMUX_H | ||
2 | #define _LINUX_GSMMUX_H | ||
3 | |||
4 | struct gsm_config | ||
5 | { | ||
6 | unsigned int adaption; | ||
7 | unsigned int encapsulation; | ||
8 | unsigned int initiator; | ||
9 | unsigned int t1; | ||
10 | unsigned int t2; | ||
11 | unsigned int t3; | ||
12 | unsigned int n2; | ||
13 | unsigned int mru; | ||
14 | unsigned int mtu; | ||
15 | unsigned int k; | ||
16 | unsigned int i; | ||
17 | unsigned int unused[8]; /* Padding for expansion without | ||
18 | breaking stuff */ | ||
19 | }; | ||
20 | |||
21 | #define GSMIOC_GETCONF _IOR('G', 0, struct gsm_config) | ||
22 | #define GSMIOC_SETCONF _IOW('G', 1, struct gsm_config) | ||
23 | |||
24 | |||
25 | #endif | ||
diff --git a/include/linux/tty.h b/include/linux/tty.h index 7e605e4b3da3..931078b73226 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h | |||
@@ -48,6 +48,7 @@ | |||
48 | #define N_PPS 18 /* Pulse per Second */ | 48 | #define N_PPS 18 /* Pulse per Second */ |
49 | #define N_V253 19 /* Codec control over voice modem */ | 49 | #define N_V253 19 /* Codec control over voice modem */ |
50 | #define N_CAIF 20 /* CAIF protocol for talking to modems */ | 50 | #define N_CAIF 20 /* CAIF protocol for talking to modems */ |
51 | #define N_GSM0710 21 /* GSM 0710 Mux */ | ||
51 | 52 | ||
52 | /* | 53 | /* |
53 | * This character is the same as _POSIX_VDISABLE: it cannot be used as | 54 | * This character is the same as _POSIX_VDISABLE: it cannot be used as |