Commit | Line | Data |
---|---|---|
76bb4685 HL |
1 | /* |
2 | * Common data handling layer for bas_gigaset | |
3 | * | |
4 | * Copyright (c) 2005 by Tilman Schmidt <tilman@imap.cc>, | |
5 | * Hansjoerg Lipp <hjlipp@web.de>. | |
6 | * | |
7 | * ===================================================================== | |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License as | |
10 | * published by the Free Software Foundation; either version 2 of | |
11 | * the License, or (at your option) any later version. | |
12 | * ===================================================================== | |
76bb4685 HL |
13 | */ |
14 | ||
15 | #include "gigaset.h" | |
16 | #include <linux/crc-ccitt.h> | |
17b3cff0 | 17 | #include <linux/bitrev.h> |
76bb4685 HL |
18 | |
19 | /* access methods for isowbuf_t */ | |
20 | /* ============================ */ | |
21 | ||
22 | /* initialize buffer structure | |
23 | */ | |
24 | void gigaset_isowbuf_init(struct isowbuf_t *iwb, unsigned char idle) | |
25 | { | |
9d4bee2b TS |
26 | iwb->read = 0; |
27 | iwb->nextread = 0; | |
28 | iwb->write = 0; | |
76bb4685 HL |
29 | atomic_set(&iwb->writesem, 1); |
30 | iwb->wbits = 0; | |
31 | iwb->idle = idle; | |
32 | memset(iwb->data + BAS_OUTBUFSIZE, idle, BAS_OUTBUFPAD); | |
33 | } | |
34 | ||
35 | /* compute number of bytes which can be appended to buffer | |
36 | * so that there is still room to append a maximum frame of flags | |
37 | */ | |
38 | static inline int isowbuf_freebytes(struct isowbuf_t *iwb) | |
39 | { | |
40 | int read, write, freebytes; | |
41 | ||
9d4bee2b TS |
42 | read = iwb->read; |
43 | write = iwb->write; | |
76bb4685 HL |
44 | if ((freebytes = read - write) > 0) { |
45 | /* no wraparound: need padding space within regular area */ | |
46 | return freebytes - BAS_OUTBUFPAD; | |
47 | } else if (read < BAS_OUTBUFPAD) { | |
48 | /* wraparound: can use space up to end of regular area */ | |
49 | return BAS_OUTBUFSIZE - write; | |
50 | } else { | |
51 | /* following the wraparound yields more space */ | |
52 | return freebytes + BAS_OUTBUFSIZE - BAS_OUTBUFPAD; | |
53 | } | |
54 | } | |
55 | ||
56 | /* compare two offsets within the buffer | |
57 | * The buffer is seen as circular, with the read position as start | |
58 | * returns -1/0/1 if position a </=/> position b without crossing 'read' | |
59 | */ | |
60 | static inline int isowbuf_poscmp(struct isowbuf_t *iwb, int a, int b) | |
61 | { | |
62 | int read; | |
63 | if (a == b) | |
64 | return 0; | |
9d4bee2b | 65 | read = iwb->read; |
76bb4685 HL |
66 | if (a < b) { |
67 | if (a < read && read <= b) | |
68 | return +1; | |
69 | else | |
70 | return -1; | |
71 | } else { | |
72 | if (b < read && read <= a) | |
73 | return -1; | |
74 | else | |
75 | return +1; | |
76 | } | |
77 | } | |
78 | ||
79 | /* start writing | |
80 | * acquire the write semaphore | |
81 | * return true if acquired, false if busy | |
82 | */ | |
83 | static inline int isowbuf_startwrite(struct isowbuf_t *iwb) | |
84 | { | |
85 | if (!atomic_dec_and_test(&iwb->writesem)) { | |
86 | atomic_inc(&iwb->writesem); | |
784d5858 TS |
87 | gig_dbg(DEBUG_ISO, "%s: couldn't acquire iso write semaphore", |
88 | __func__); | |
76bb4685 HL |
89 | return 0; |
90 | } | |
91 | #ifdef CONFIG_GIGASET_DEBUG | |
784d5858 TS |
92 | gig_dbg(DEBUG_ISO, |
93 | "%s: acquired iso write semaphore, data[write]=%02x, nbits=%d", | |
9d4bee2b | 94 | __func__, iwb->data[iwb->write], iwb->wbits); |
76bb4685 HL |
95 | #endif |
96 | return 1; | |
97 | } | |
98 | ||
99 | /* finish writing | |
9d4bee2b | 100 | * release the write semaphore |
76bb4685 HL |
101 | * returns the current write position |
102 | */ | |
103 | static inline int isowbuf_donewrite(struct isowbuf_t *iwb) | |
104 | { | |
9d4bee2b | 105 | int write = iwb->write; |
76bb4685 HL |
106 | atomic_inc(&iwb->writesem); |
107 | return write; | |
108 | } | |
109 | ||
110 | /* append bits to buffer without any checks | |
111 | * - data contains bits to append, starting at LSB | |
112 | * - nbits is number of bits to append (0..24) | |
113 | * must be called with the write semaphore held | |
114 | * If more than nbits bits are set in data, the extraneous bits are set in the | |
115 | * buffer too, but the write position is only advanced by nbits. | |
116 | */ | |
117 | static inline void isowbuf_putbits(struct isowbuf_t *iwb, u32 data, int nbits) | |
118 | { | |
9d4bee2b | 119 | int write = iwb->write; |
76bb4685 HL |
120 | data <<= iwb->wbits; |
121 | data |= iwb->data[write]; | |
122 | nbits += iwb->wbits; | |
123 | while (nbits >= 8) { | |
124 | iwb->data[write++] = data & 0xff; | |
125 | write %= BAS_OUTBUFSIZE; | |
126 | data >>= 8; | |
127 | nbits -= 8; | |
128 | } | |
129 | iwb->wbits = nbits; | |
130 | iwb->data[write] = data & 0xff; | |
9d4bee2b | 131 | iwb->write = write; |
76bb4685 HL |
132 | } |
133 | ||
134 | /* put final flag on HDLC bitstream | |
135 | * also sets the idle fill byte to the correspondingly shifted flag pattern | |
136 | * must be called with the write semaphore held | |
137 | */ | |
138 | static inline void isowbuf_putflag(struct isowbuf_t *iwb) | |
139 | { | |
140 | int write; | |
141 | ||
142 | /* add two flags, thus reliably covering one byte */ | |
143 | isowbuf_putbits(iwb, 0x7e7e, 8); | |
144 | /* recover the idle flag byte */ | |
9d4bee2b | 145 | write = iwb->write; |
76bb4685 | 146 | iwb->idle = iwb->data[write]; |
784d5858 | 147 | gig_dbg(DEBUG_ISO, "idle fill byte %02x", iwb->idle); |
76bb4685 HL |
148 | /* mask extraneous bits in buffer */ |
149 | iwb->data[write] &= (1 << iwb->wbits) - 1; | |
150 | } | |
151 | ||
152 | /* retrieve a block of bytes for sending | |
153 | * The requested number of bytes is provided as a contiguous block. | |
154 | * If necessary, the frame is filled to the requested number of bytes | |
155 | * with the idle value. | |
156 | * returns offset to frame, < 0 on busy or error | |
157 | */ | |
158 | int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size) | |
159 | { | |
160 | int read, write, limit, src, dst; | |
161 | unsigned char pbyte; | |
162 | ||
9d4bee2b TS |
163 | read = iwb->nextread; |
164 | write = iwb->write; | |
76bb4685 | 165 | if (likely(read == write)) { |
76bb4685 HL |
166 | /* return idle frame */ |
167 | return read < BAS_OUTBUFPAD ? | |
784d5858 | 168 | BAS_OUTBUFSIZE : read - BAS_OUTBUFPAD; |
76bb4685 HL |
169 | } |
170 | ||
171 | limit = read + size; | |
784d5858 TS |
172 | gig_dbg(DEBUG_STREAM, "%s: read=%d write=%d limit=%d", |
173 | __func__, read, write, limit); | |
76bb4685 HL |
174 | #ifdef CONFIG_GIGASET_DEBUG |
175 | if (unlikely(size < 0 || size > BAS_OUTBUFPAD)) { | |
176 | err("invalid size %d", size); | |
177 | return -EINVAL; | |
178 | } | |
9d4bee2b | 179 | src = iwb->read; |
76bb4685 HL |
180 | if (unlikely(limit > BAS_OUTBUFSIZE + BAS_OUTBUFPAD || |
181 | (read < src && limit >= src))) { | |
182 | err("isoc write buffer frame reservation violated"); | |
183 | return -EFAULT; | |
184 | } | |
185 | #endif | |
186 | ||
187 | if (read < write) { | |
188 | /* no wraparound in valid data */ | |
189 | if (limit >= write) { | |
190 | /* append idle frame */ | |
191 | if (!isowbuf_startwrite(iwb)) | |
192 | return -EBUSY; | |
193 | /* write position could have changed */ | |
9d4bee2b TS |
194 | write = iwb->write; |
195 | if (limit >= write) { | |
917f5085 TS |
196 | pbyte = iwb->data[write]; /* save |
197 | partial byte */ | |
76bb4685 | 198 | limit = write + BAS_OUTBUFPAD; |
784d5858 TS |
199 | gig_dbg(DEBUG_STREAM, |
200 | "%s: filling %d->%d with %02x", | |
201 | __func__, write, limit, iwb->idle); | |
76bb4685 HL |
202 | if (write + BAS_OUTBUFPAD < BAS_OUTBUFSIZE) |
203 | memset(iwb->data + write, iwb->idle, | |
204 | BAS_OUTBUFPAD); | |
205 | else { | |
206 | /* wraparound, fill entire pad area */ | |
207 | memset(iwb->data + write, iwb->idle, | |
208 | BAS_OUTBUFSIZE + BAS_OUTBUFPAD | |
209 | - write); | |
210 | limit = 0; | |
211 | } | |
784d5858 TS |
212 | gig_dbg(DEBUG_STREAM, |
213 | "%s: restoring %02x at %d", | |
214 | __func__, pbyte, limit); | |
917f5085 TS |
215 | iwb->data[limit] = pbyte; /* restore |
216 | partial byte */ | |
9d4bee2b | 217 | iwb->write = limit; |
76bb4685 HL |
218 | } |
219 | isowbuf_donewrite(iwb); | |
220 | } | |
221 | } else { | |
222 | /* valid data wraparound */ | |
223 | if (limit >= BAS_OUTBUFSIZE) { | |
224 | /* copy wrapped part into pad area */ | |
225 | src = 0; | |
226 | dst = BAS_OUTBUFSIZE; | |
227 | while (dst < limit && src < write) | |
228 | iwb->data[dst++] = iwb->data[src++]; | |
229 | if (dst <= limit) { | |
230 | /* fill pad area with idle byte */ | |
231 | memset(iwb->data + dst, iwb->idle, | |
232 | BAS_OUTBUFSIZE + BAS_OUTBUFPAD - dst); | |
233 | } | |
234 | limit = src; | |
235 | } | |
236 | } | |
9d4bee2b | 237 | iwb->nextread = limit; |
76bb4685 HL |
238 | return read; |
239 | } | |
240 | ||
241 | /* dump_bytes | |
242 | * write hex bytes to syslog for debugging | |
243 | */ | |
244 | static inline void dump_bytes(enum debuglevel level, const char *tag, | |
784d5858 | 245 | unsigned char *bytes, int count) |
76bb4685 HL |
246 | { |
247 | #ifdef CONFIG_GIGASET_DEBUG | |
248 | unsigned char c; | |
249 | static char dbgline[3 * 32 + 1]; | |
76bb4685 | 250 | int i = 0; |
76bb4685 HL |
251 | while (count-- > 0) { |
252 | if (i > sizeof(dbgline) - 4) { | |
253 | dbgline[i] = '\0'; | |
784d5858 | 254 | gig_dbg(level, "%s:%s", tag, dbgline); |
76bb4685 HL |
255 | i = 0; |
256 | } | |
257 | c = *bytes++; | |
258 | dbgline[i] = (i && !(i % 12)) ? '-' : ' '; | |
259 | i++; | |
02137f2e HH |
260 | dbgline[i++] = hex_asc_hi(c); |
261 | dbgline[i++] = hex_asc_lo(c); | |
76bb4685 HL |
262 | } |
263 | dbgline[i] = '\0'; | |
784d5858 | 264 | gig_dbg(level, "%s:%s", tag, dbgline); |
76bb4685 HL |
265 | #endif |
266 | } | |
267 | ||
268 | /*============================================================================*/ | |
269 | ||
270 | /* bytewise HDLC bitstuffing via table lookup | |
271 | * lookup table: 5 subtables for 0..4 preceding consecutive '1' bits | |
272 | * index: 256*(number of preceding '1' bits) + (next byte to stuff) | |
273 | * value: bit 9.. 0 = result bits | |
274 | * bit 12..10 = number of trailing '1' bits in result | |
275 | * bit 14..13 = number of bits added by stuffing | |
276 | */ | |
35dc8457 | 277 | static const u16 stufftab[5 * 256] = { |
76bb4685 HL |
278 | // previous 1s = 0: |
279 | 0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007, 0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f, | |
280 | 0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017, 0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x201f, | |
281 | 0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027, 0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x002f, | |
282 | 0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037, 0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x203e, 0x205f, | |
283 | 0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047, 0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x004f, | |
284 | 0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057, 0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x209f, | |
285 | 0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067, 0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x006f, | |
286 | 0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077, 0x0078, 0x0079, 0x007a, 0x007b, 0x207c, 0x207d, 0x20be, 0x20df, | |
287 | 0x0480, 0x0481, 0x0482, 0x0483, 0x0484, 0x0485, 0x0486, 0x0487, 0x0488, 0x0489, 0x048a, 0x048b, 0x048c, 0x048d, 0x048e, 0x048f, | |
288 | 0x0490, 0x0491, 0x0492, 0x0493, 0x0494, 0x0495, 0x0496, 0x0497, 0x0498, 0x0499, 0x049a, 0x049b, 0x049c, 0x049d, 0x049e, 0x251f, | |
289 | 0x04a0, 0x04a1, 0x04a2, 0x04a3, 0x04a4, 0x04a5, 0x04a6, 0x04a7, 0x04a8, 0x04a9, 0x04aa, 0x04ab, 0x04ac, 0x04ad, 0x04ae, 0x04af, | |
290 | 0x04b0, 0x04b1, 0x04b2, 0x04b3, 0x04b4, 0x04b5, 0x04b6, 0x04b7, 0x04b8, 0x04b9, 0x04ba, 0x04bb, 0x04bc, 0x04bd, 0x253e, 0x255f, | |
291 | 0x08c0, 0x08c1, 0x08c2, 0x08c3, 0x08c4, 0x08c5, 0x08c6, 0x08c7, 0x08c8, 0x08c9, 0x08ca, 0x08cb, 0x08cc, 0x08cd, 0x08ce, 0x08cf, | |
292 | 0x08d0, 0x08d1, 0x08d2, 0x08d3, 0x08d4, 0x08d5, 0x08d6, 0x08d7, 0x08d8, 0x08d9, 0x08da, 0x08db, 0x08dc, 0x08dd, 0x08de, 0x299f, | |
293 | 0x0ce0, 0x0ce1, 0x0ce2, 0x0ce3, 0x0ce4, 0x0ce5, 0x0ce6, 0x0ce7, 0x0ce8, 0x0ce9, 0x0cea, 0x0ceb, 0x0cec, 0x0ced, 0x0cee, 0x0cef, | |
294 | 0x10f0, 0x10f1, 0x10f2, 0x10f3, 0x10f4, 0x10f5, 0x10f6, 0x10f7, 0x20f8, 0x20f9, 0x20fa, 0x20fb, 0x257c, 0x257d, 0x29be, 0x2ddf, | |
295 | ||
296 | // previous 1s = 1: | |
297 | 0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007, 0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x200f, | |
298 | 0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017, 0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x202f, | |
299 | 0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027, 0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x204f, | |
300 | 0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037, 0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x203e, 0x206f, | |
301 | 0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047, 0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x208f, | |
302 | 0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057, 0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x20af, | |
303 | 0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067, 0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x20cf, | |
304 | 0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077, 0x0078, 0x0079, 0x007a, 0x007b, 0x207c, 0x207d, 0x20be, 0x20ef, | |
305 | 0x0480, 0x0481, 0x0482, 0x0483, 0x0484, 0x0485, 0x0486, 0x0487, 0x0488, 0x0489, 0x048a, 0x048b, 0x048c, 0x048d, 0x048e, 0x250f, | |
306 | 0x0490, 0x0491, 0x0492, 0x0493, 0x0494, 0x0495, 0x0496, 0x0497, 0x0498, 0x0499, 0x049a, 0x049b, 0x049c, 0x049d, 0x049e, 0x252f, | |
307 | 0x04a0, 0x04a1, 0x04a2, 0x04a3, 0x04a4, 0x04a5, 0x04a6, 0x04a7, 0x04a8, 0x04a9, 0x04aa, 0x04ab, 0x04ac, 0x04ad, 0x04ae, 0x254f, | |
308 | 0x04b0, 0x04b1, 0x04b2, 0x04b3, 0x04b4, 0x04b5, 0x04b6, 0x04b7, 0x04b8, 0x04b9, 0x04ba, 0x04bb, 0x04bc, 0x04bd, 0x253e, 0x256f, | |
309 | 0x08c0, 0x08c1, 0x08c2, 0x08c3, 0x08c4, 0x08c5, 0x08c6, 0x08c7, 0x08c8, 0x08c9, 0x08ca, 0x08cb, 0x08cc, 0x08cd, 0x08ce, 0x298f, | |
310 | 0x08d0, 0x08d1, 0x08d2, 0x08d3, 0x08d4, 0x08d5, 0x08d6, 0x08d7, 0x08d8, 0x08d9, 0x08da, 0x08db, 0x08dc, 0x08dd, 0x08de, 0x29af, | |
311 | 0x0ce0, 0x0ce1, 0x0ce2, 0x0ce3, 0x0ce4, 0x0ce5, 0x0ce6, 0x0ce7, 0x0ce8, 0x0ce9, 0x0cea, 0x0ceb, 0x0cec, 0x0ced, 0x0cee, 0x2dcf, | |
312 | 0x10f0, 0x10f1, 0x10f2, 0x10f3, 0x10f4, 0x10f5, 0x10f6, 0x10f7, 0x20f8, 0x20f9, 0x20fa, 0x20fb, 0x257c, 0x257d, 0x29be, 0x31ef, | |
313 | ||
314 | // previous 1s = 2: | |
315 | 0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x2007, 0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x2017, | |
316 | 0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x2027, 0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x2037, | |
317 | 0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x2047, 0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x2057, | |
318 | 0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x2067, 0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x203e, 0x2077, | |
319 | 0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x2087, 0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x2097, | |
320 | 0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x20a7, 0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x20b7, | |
321 | 0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x20c7, 0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x20d7, | |
322 | 0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x20e7, 0x0078, 0x0079, 0x007a, 0x007b, 0x207c, 0x207d, 0x20be, 0x20f7, | |
323 | 0x0480, 0x0481, 0x0482, 0x0483, 0x0484, 0x0485, 0x0486, 0x2507, 0x0488, 0x0489, 0x048a, 0x048b, 0x048c, 0x048d, 0x048e, 0x2517, | |
324 | 0x0490, 0x0491, 0x0492, 0x0493, 0x0494, 0x0495, 0x0496, 0x2527, 0x0498, 0x0499, 0x049a, 0x049b, 0x049c, 0x049d, 0x049e, 0x2537, | |
325 | 0x04a0, 0x04a1, 0x04a2, 0x04a3, 0x04a4, 0x04a5, 0x04a6, 0x2547, 0x04a8, 0x04a9, 0x04aa, 0x04ab, 0x04ac, 0x04ad, 0x04ae, 0x2557, | |
326 | 0x04b0, 0x04b1, 0x04b2, 0x04b3, 0x04b4, 0x04b5, 0x04b6, 0x2567, 0x04b8, 0x04b9, 0x04ba, 0x04bb, 0x04bc, 0x04bd, 0x253e, 0x2577, | |
327 | 0x08c0, 0x08c1, 0x08c2, 0x08c3, 0x08c4, 0x08c5, 0x08c6, 0x2987, 0x08c8, 0x08c9, 0x08ca, 0x08cb, 0x08cc, 0x08cd, 0x08ce, 0x2997, | |
328 | 0x08d0, 0x08d1, 0x08d2, 0x08d3, 0x08d4, 0x08d5, 0x08d6, 0x29a7, 0x08d8, 0x08d9, 0x08da, 0x08db, 0x08dc, 0x08dd, 0x08de, 0x29b7, | |
329 | 0x0ce0, 0x0ce1, 0x0ce2, 0x0ce3, 0x0ce4, 0x0ce5, 0x0ce6, 0x2dc7, 0x0ce8, 0x0ce9, 0x0cea, 0x0ceb, 0x0cec, 0x0ced, 0x0cee, 0x2dd7, | |
330 | 0x10f0, 0x10f1, 0x10f2, 0x10f3, 0x10f4, 0x10f5, 0x10f6, 0x31e7, 0x20f8, 0x20f9, 0x20fa, 0x20fb, 0x257c, 0x257d, 0x29be, 0x41f7, | |
331 | ||
332 | // previous 1s = 3: | |
333 | 0x0000, 0x0001, 0x0002, 0x2003, 0x0004, 0x0005, 0x0006, 0x200b, 0x0008, 0x0009, 0x000a, 0x2013, 0x000c, 0x000d, 0x000e, 0x201b, | |
334 | 0x0010, 0x0011, 0x0012, 0x2023, 0x0014, 0x0015, 0x0016, 0x202b, 0x0018, 0x0019, 0x001a, 0x2033, 0x001c, 0x001d, 0x001e, 0x203b, | |
335 | 0x0020, 0x0021, 0x0022, 0x2043, 0x0024, 0x0025, 0x0026, 0x204b, 0x0028, 0x0029, 0x002a, 0x2053, 0x002c, 0x002d, 0x002e, 0x205b, | |
336 | 0x0030, 0x0031, 0x0032, 0x2063, 0x0034, 0x0035, 0x0036, 0x206b, 0x0038, 0x0039, 0x003a, 0x2073, 0x003c, 0x003d, 0x203e, 0x207b, | |
337 | 0x0040, 0x0041, 0x0042, 0x2083, 0x0044, 0x0045, 0x0046, 0x208b, 0x0048, 0x0049, 0x004a, 0x2093, 0x004c, 0x004d, 0x004e, 0x209b, | |
338 | 0x0050, 0x0051, 0x0052, 0x20a3, 0x0054, 0x0055, 0x0056, 0x20ab, 0x0058, 0x0059, 0x005a, 0x20b3, 0x005c, 0x005d, 0x005e, 0x20bb, | |
339 | 0x0060, 0x0061, 0x0062, 0x20c3, 0x0064, 0x0065, 0x0066, 0x20cb, 0x0068, 0x0069, 0x006a, 0x20d3, 0x006c, 0x006d, 0x006e, 0x20db, | |
340 | 0x0070, 0x0071, 0x0072, 0x20e3, 0x0074, 0x0075, 0x0076, 0x20eb, 0x0078, 0x0079, 0x007a, 0x20f3, 0x207c, 0x207d, 0x20be, 0x40fb, | |
341 | 0x0480, 0x0481, 0x0482, 0x2503, 0x0484, 0x0485, 0x0486, 0x250b, 0x0488, 0x0489, 0x048a, 0x2513, 0x048c, 0x048d, 0x048e, 0x251b, | |
342 | 0x0490, 0x0491, 0x0492, 0x2523, 0x0494, 0x0495, 0x0496, 0x252b, 0x0498, 0x0499, 0x049a, 0x2533, 0x049c, 0x049d, 0x049e, 0x253b, | |
343 | 0x04a0, 0x04a1, 0x04a2, 0x2543, 0x04a4, 0x04a5, 0x04a6, 0x254b, 0x04a8, 0x04a9, 0x04aa, 0x2553, 0x04ac, 0x04ad, 0x04ae, 0x255b, | |
344 | 0x04b0, 0x04b1, 0x04b2, 0x2563, 0x04b4, 0x04b5, 0x04b6, 0x256b, 0x04b8, 0x04b9, 0x04ba, 0x2573, 0x04bc, 0x04bd, 0x253e, 0x257b, | |
345 | 0x08c0, 0x08c1, 0x08c2, 0x2983, 0x08c4, 0x08c5, 0x08c6, 0x298b, 0x08c8, 0x08c9, 0x08ca, 0x2993, 0x08cc, 0x08cd, 0x08ce, 0x299b, | |
346 | 0x08d0, 0x08d1, 0x08d2, 0x29a3, 0x08d4, 0x08d5, 0x08d6, 0x29ab, 0x08d8, 0x08d9, 0x08da, 0x29b3, 0x08dc, 0x08dd, 0x08de, 0x29bb, | |
347 | 0x0ce0, 0x0ce1, 0x0ce2, 0x2dc3, 0x0ce4, 0x0ce5, 0x0ce6, 0x2dcb, 0x0ce8, 0x0ce9, 0x0cea, 0x2dd3, 0x0cec, 0x0ced, 0x0cee, 0x2ddb, | |
348 | 0x10f0, 0x10f1, 0x10f2, 0x31e3, 0x10f4, 0x10f5, 0x10f6, 0x31eb, 0x20f8, 0x20f9, 0x20fa, 0x41f3, 0x257c, 0x257d, 0x29be, 0x46fb, | |
349 | ||
350 | // previous 1s = 4: | |
351 | 0x0000, 0x2001, 0x0002, 0x2005, 0x0004, 0x2009, 0x0006, 0x200d, 0x0008, 0x2011, 0x000a, 0x2015, 0x000c, 0x2019, 0x000e, 0x201d, | |
352 | 0x0010, 0x2021, 0x0012, 0x2025, 0x0014, 0x2029, 0x0016, 0x202d, 0x0018, 0x2031, 0x001a, 0x2035, 0x001c, 0x2039, 0x001e, 0x203d, | |
353 | 0x0020, 0x2041, 0x0022, 0x2045, 0x0024, 0x2049, 0x0026, 0x204d, 0x0028, 0x2051, 0x002a, 0x2055, 0x002c, 0x2059, 0x002e, 0x205d, | |
354 | 0x0030, 0x2061, 0x0032, 0x2065, 0x0034, 0x2069, 0x0036, 0x206d, 0x0038, 0x2071, 0x003a, 0x2075, 0x003c, 0x2079, 0x203e, 0x407d, | |
355 | 0x0040, 0x2081, 0x0042, 0x2085, 0x0044, 0x2089, 0x0046, 0x208d, 0x0048, 0x2091, 0x004a, 0x2095, 0x004c, 0x2099, 0x004e, 0x209d, | |
356 | 0x0050, 0x20a1, 0x0052, 0x20a5, 0x0054, 0x20a9, 0x0056, 0x20ad, 0x0058, 0x20b1, 0x005a, 0x20b5, 0x005c, 0x20b9, 0x005e, 0x20bd, | |
357 | 0x0060, 0x20c1, 0x0062, 0x20c5, 0x0064, 0x20c9, 0x0066, 0x20cd, 0x0068, 0x20d1, 0x006a, 0x20d5, 0x006c, 0x20d9, 0x006e, 0x20dd, | |
358 | 0x0070, 0x20e1, 0x0072, 0x20e5, 0x0074, 0x20e9, 0x0076, 0x20ed, 0x0078, 0x20f1, 0x007a, 0x20f5, 0x207c, 0x40f9, 0x20be, 0x417d, | |
359 | 0x0480, 0x2501, 0x0482, 0x2505, 0x0484, 0x2509, 0x0486, 0x250d, 0x0488, 0x2511, 0x048a, 0x2515, 0x048c, 0x2519, 0x048e, 0x251d, | |
360 | 0x0490, 0x2521, 0x0492, 0x2525, 0x0494, 0x2529, 0x0496, 0x252d, 0x0498, 0x2531, 0x049a, 0x2535, 0x049c, 0x2539, 0x049e, 0x253d, | |
361 | 0x04a0, 0x2541, 0x04a2, 0x2545, 0x04a4, 0x2549, 0x04a6, 0x254d, 0x04a8, 0x2551, 0x04aa, 0x2555, 0x04ac, 0x2559, 0x04ae, 0x255d, | |
362 | 0x04b0, 0x2561, 0x04b2, 0x2565, 0x04b4, 0x2569, 0x04b6, 0x256d, 0x04b8, 0x2571, 0x04ba, 0x2575, 0x04bc, 0x2579, 0x253e, 0x467d, | |
363 | 0x08c0, 0x2981, 0x08c2, 0x2985, 0x08c4, 0x2989, 0x08c6, 0x298d, 0x08c8, 0x2991, 0x08ca, 0x2995, 0x08cc, 0x2999, 0x08ce, 0x299d, | |
364 | 0x08d0, 0x29a1, 0x08d2, 0x29a5, 0x08d4, 0x29a9, 0x08d6, 0x29ad, 0x08d8, 0x29b1, 0x08da, 0x29b5, 0x08dc, 0x29b9, 0x08de, 0x29bd, | |
365 | 0x0ce0, 0x2dc1, 0x0ce2, 0x2dc5, 0x0ce4, 0x2dc9, 0x0ce6, 0x2dcd, 0x0ce8, 0x2dd1, 0x0cea, 0x2dd5, 0x0cec, 0x2dd9, 0x0cee, 0x2ddd, | |
366 | 0x10f0, 0x31e1, 0x10f2, 0x31e5, 0x10f4, 0x31e9, 0x10f6, 0x31ed, 0x20f8, 0x41f1, 0x20fa, 0x41f5, 0x257c, 0x46f9, 0x29be, 0x4b7d | |
367 | }; | |
368 | ||
369 | /* hdlc_bitstuff_byte | |
370 | * perform HDLC bitstuffing for one input byte (8 bits, LSB first) | |
371 | * parameters: | |
372 | * cin input byte | |
373 | * ones number of trailing '1' bits in result before this step | |
374 | * iwb pointer to output buffer structure (write semaphore must be held) | |
375 | * return value: | |
376 | * number of trailing '1' bits in result after this step | |
377 | */ | |
378 | ||
379 | static inline int hdlc_bitstuff_byte(struct isowbuf_t *iwb, unsigned char cin, | |
784d5858 | 380 | int ones) |
76bb4685 HL |
381 | { |
382 | u16 stuff; | |
383 | int shiftinc, newones; | |
384 | ||
385 | /* get stuffing information for input byte | |
386 | * value: bit 9.. 0 = result bits | |
387 | * bit 12..10 = number of trailing '1' bits in result | |
388 | * bit 14..13 = number of bits added by stuffing | |
389 | */ | |
390 | stuff = stufftab[256 * ones + cin]; | |
391 | shiftinc = (stuff >> 13) & 3; | |
392 | newones = (stuff >> 10) & 7; | |
393 | stuff &= 0x3ff; | |
394 | ||
395 | /* append stuffed byte to output stream */ | |
396 | isowbuf_putbits(iwb, stuff, 8 + shiftinc); | |
397 | return newones; | |
398 | } | |
399 | ||
400 | /* hdlc_buildframe | |
401 | * Perform HDLC framing with bitstuffing on a byte buffer | |
402 | * The input buffer is regarded as a sequence of bits, starting with the least | |
403 | * significant bit of the first byte and ending with the most significant bit | |
404 | * of the last byte. A 16 bit FCS is appended as defined by RFC 1662. | |
405 | * Whenever five consecutive '1' bits appear in the resulting bit sequence, a | |
406 | * '0' bit is inserted after them. | |
407 | * The resulting bit string and a closing flag pattern (PPP_FLAG, '01111110') | |
408 | * are appended to the output buffer starting at the given bit position, which | |
409 | * is assumed to already contain a leading flag. | |
410 | * The output buffer must have sufficient length; count + count/5 + 6 bytes | |
411 | * starting at *out are safe and are verified to be present. | |
412 | * parameters: | |
413 | * in input buffer | |
414 | * count number of bytes in input buffer | |
415 | * iwb pointer to output buffer structure (write semaphore must be held) | |
416 | * return value: | |
417 | * position of end of packet in output buffer on success, | |
418 | * -EAGAIN if write semaphore busy or buffer full | |
419 | */ | |
420 | ||
421 | static inline int hdlc_buildframe(struct isowbuf_t *iwb, | |
784d5858 | 422 | unsigned char *in, int count) |
76bb4685 HL |
423 | { |
424 | int ones; | |
425 | u16 fcs; | |
426 | int end; | |
427 | unsigned char c; | |
428 | ||
429 | if (isowbuf_freebytes(iwb) < count + count / 5 + 6 || | |
430 | !isowbuf_startwrite(iwb)) { | |
784d5858 TS |
431 | gig_dbg(DEBUG_ISO, "%s: %d bytes free -> -EAGAIN", |
432 | __func__, isowbuf_freebytes(iwb)); | |
76bb4685 HL |
433 | return -EAGAIN; |
434 | } | |
435 | ||
436 | dump_bytes(DEBUG_STREAM, "snd data", in, count); | |
437 | ||
438 | /* bitstuff and checksum input data */ | |
439 | fcs = PPP_INITFCS; | |
440 | ones = 0; | |
441 | while (count-- > 0) { | |
442 | c = *in++; | |
443 | ones = hdlc_bitstuff_byte(iwb, c, ones); | |
444 | fcs = crc_ccitt_byte(fcs, c); | |
445 | } | |
446 | ||
447 | /* bitstuff and append FCS (complemented, least significant byte first) */ | |
448 | fcs ^= 0xffff; | |
449 | ones = hdlc_bitstuff_byte(iwb, fcs & 0x00ff, ones); | |
450 | ones = hdlc_bitstuff_byte(iwb, (fcs >> 8) & 0x00ff, ones); | |
451 | ||
452 | /* put closing flag and repeat byte for flag idle */ | |
453 | isowbuf_putflag(iwb); | |
454 | end = isowbuf_donewrite(iwb); | |
455 | dump_bytes(DEBUG_STREAM_DUMP, "isowbuf", iwb->data, end + 1); | |
456 | return end; | |
457 | } | |
458 | ||
459 | /* trans_buildframe | |
460 | * Append a block of 'transparent' data to the output buffer, | |
461 | * inverting the bytes. | |
462 | * The output buffer must have sufficient length; count bytes | |
463 | * starting at *out are safe and are verified to be present. | |
464 | * parameters: | |
465 | * in input buffer | |
466 | * count number of bytes in input buffer | |
467 | * iwb pointer to output buffer structure (write semaphore must be held) | |
468 | * return value: | |
469 | * position of end of packet in output buffer on success, | |
470 | * -EAGAIN if write semaphore busy or buffer full | |
471 | */ | |
472 | ||
473 | static inline int trans_buildframe(struct isowbuf_t *iwb, | |
474 | unsigned char *in, int count) | |
475 | { | |
476 | int write; | |
477 | unsigned char c; | |
478 | ||
479 | if (unlikely(count <= 0)) | |
9d4bee2b | 480 | return iwb->write; |
76bb4685 HL |
481 | |
482 | if (isowbuf_freebytes(iwb) < count || | |
483 | !isowbuf_startwrite(iwb)) { | |
784d5858 | 484 | gig_dbg(DEBUG_ISO, "can't put %d bytes", count); |
76bb4685 HL |
485 | return -EAGAIN; |
486 | } | |
487 | ||
784d5858 | 488 | gig_dbg(DEBUG_STREAM, "put %d bytes", count); |
9d4bee2b | 489 | write = iwb->write; |
76bb4685 | 490 | do { |
17b3cff0 | 491 | c = bitrev8(*in++); |
76bb4685 HL |
492 | iwb->data[write++] = c; |
493 | write %= BAS_OUTBUFSIZE; | |
494 | } while (--count > 0); | |
9d4bee2b | 495 | iwb->write = write; |
76bb4685 HL |
496 | iwb->idle = c; |
497 | ||
498 | return isowbuf_donewrite(iwb); | |
499 | } | |
500 | ||
501 | int gigaset_isoc_buildframe(struct bc_state *bcs, unsigned char *in, int len) | |
502 | { | |
503 | int result; | |
504 | ||
505 | switch (bcs->proto2) { | |
506 | case ISDN_PROTO_L2_HDLC: | |
507 | result = hdlc_buildframe(bcs->hw.bas->isooutbuf, in, len); | |
784d5858 TS |
508 | gig_dbg(DEBUG_ISO, "%s: %d bytes HDLC -> %d", |
509 | __func__, len, result); | |
76bb4685 HL |
510 | break; |
511 | default: /* assume transparent */ | |
512 | result = trans_buildframe(bcs->hw.bas->isooutbuf, in, len); | |
784d5858 TS |
513 | gig_dbg(DEBUG_ISO, "%s: %d bytes trans -> %d", |
514 | __func__, len, result); | |
76bb4685 HL |
515 | } |
516 | return result; | |
517 | } | |
518 | ||
519 | /* hdlc_putbyte | |
520 | * append byte c to current skb of B channel structure *bcs, updating fcs | |
521 | */ | |
522 | static inline void hdlc_putbyte(unsigned char c, struct bc_state *bcs) | |
523 | { | |
524 | bcs->fcs = crc_ccitt_byte(bcs->fcs, c); | |
525 | if (unlikely(bcs->skb == NULL)) { | |
526 | /* skipping */ | |
527 | return; | |
528 | } | |
529 | if (unlikely(bcs->skb->len == SBUFSIZE)) { | |
784d5858 | 530 | dev_warn(bcs->cs->dev, "received oversized packet discarded\n"); |
76bb4685 HL |
531 | bcs->hw.bas->giants++; |
532 | dev_kfree_skb_any(bcs->skb); | |
533 | bcs->skb = NULL; | |
534 | return; | |
535 | } | |
443e1f45 | 536 | *__skb_put(bcs->skb, 1) = c; |
76bb4685 HL |
537 | } |
538 | ||
539 | /* hdlc_flush | |
540 | * drop partial HDLC data packet | |
541 | */ | |
542 | static inline void hdlc_flush(struct bc_state *bcs) | |
543 | { | |
544 | /* clear skb or allocate new if not skipping */ | |
545 | if (likely(bcs->skb != NULL)) | |
546 | skb_trim(bcs->skb, 0); | |
547 | else if (!bcs->ignore) { | |
548 | if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL) | |
549 | skb_reserve(bcs->skb, HW_HDR_LEN); | |
550 | else | |
784d5858 | 551 | dev_err(bcs->cs->dev, "could not allocate skb\n"); |
76bb4685 HL |
552 | } |
553 | ||
554 | /* reset packet state */ | |
555 | bcs->fcs = PPP_INITFCS; | |
556 | } | |
557 | ||
558 | /* hdlc_done | |
559 | * process completed HDLC data packet | |
560 | */ | |
561 | static inline void hdlc_done(struct bc_state *bcs) | |
562 | { | |
563 | struct sk_buff *procskb; | |
564 | ||
565 | if (unlikely(bcs->ignore)) { | |
566 | bcs->ignore--; | |
567 | hdlc_flush(bcs); | |
568 | return; | |
569 | } | |
570 | ||
571 | if ((procskb = bcs->skb) == NULL) { | |
572 | /* previous error */ | |
784d5858 | 573 | gig_dbg(DEBUG_ISO, "%s: skb=NULL", __func__); |
76bb4685 HL |
574 | gigaset_rcv_error(NULL, bcs->cs, bcs); |
575 | } else if (procskb->len < 2) { | |
784d5858 TS |
576 | dev_notice(bcs->cs->dev, "received short frame (%d octets)\n", |
577 | procskb->len); | |
76bb4685 HL |
578 | bcs->hw.bas->runts++; |
579 | gigaset_rcv_error(procskb, bcs->cs, bcs); | |
580 | } else if (bcs->fcs != PPP_GOODFCS) { | |
784d5858 TS |
581 | dev_notice(bcs->cs->dev, "frame check error (0x%04x)\n", |
582 | bcs->fcs); | |
76bb4685 HL |
583 | bcs->hw.bas->fcserrs++; |
584 | gigaset_rcv_error(procskb, bcs->cs, bcs); | |
585 | } else { | |
586 | procskb->len -= 2; /* subtract FCS */ | |
587 | procskb->tail -= 2; | |
784d5858 TS |
588 | gig_dbg(DEBUG_ISO, "%s: good frame (%d octets)", |
589 | __func__, procskb->len); | |
76bb4685 | 590 | dump_bytes(DEBUG_STREAM, |
784d5858 | 591 | "rcv data", procskb->data, procskb->len); |
76bb4685 HL |
592 | bcs->hw.bas->goodbytes += procskb->len; |
593 | gigaset_rcv_skb(procskb, bcs->cs, bcs); | |
594 | } | |
595 | ||
596 | if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL) | |
597 | skb_reserve(bcs->skb, HW_HDR_LEN); | |
598 | else | |
784d5858 | 599 | dev_err(bcs->cs->dev, "could not allocate skb\n"); |
76bb4685 HL |
600 | bcs->fcs = PPP_INITFCS; |
601 | } | |
602 | ||
603 | /* hdlc_frag | |
604 | * drop HDLC data packet with non-integral last byte | |
605 | */ | |
606 | static inline void hdlc_frag(struct bc_state *bcs, unsigned inbits) | |
607 | { | |
608 | if (unlikely(bcs->ignore)) { | |
609 | bcs->ignore--; | |
610 | hdlc_flush(bcs); | |
611 | return; | |
612 | } | |
613 | ||
784d5858 | 614 | dev_notice(bcs->cs->dev, "received partial byte (%d bits)\n", inbits); |
76bb4685 HL |
615 | bcs->hw.bas->alignerrs++; |
616 | gigaset_rcv_error(bcs->skb, bcs->cs, bcs); | |
617 | ||
618 | if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL) | |
619 | skb_reserve(bcs->skb, HW_HDR_LEN); | |
620 | else | |
784d5858 | 621 | dev_err(bcs->cs->dev, "could not allocate skb\n"); |
76bb4685 HL |
622 | bcs->fcs = PPP_INITFCS; |
623 | } | |
624 | ||
625 | /* bit counts lookup table for HDLC bit unstuffing | |
626 | * index: input byte | |
627 | * value: bit 0..3 = number of consecutive '1' bits starting from LSB | |
628 | * bit 4..6 = number of consecutive '1' bits starting from MSB | |
629 | * (replacing 8 by 7 to make it fit; the algorithm won't care) | |
630 | * bit 7 set if there are 5 or more "interior" consecutive '1' bits | |
631 | */ | |
35dc8457 | 632 | static const unsigned char bitcounts[256] = { |
76bb4685 HL |
633 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04, |
634 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x05, | |
635 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04, | |
636 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x80, 0x06, | |
637 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04, | |
638 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x05, | |
639 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04, | |
640 | 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x80, 0x81, 0x80, 0x07, | |
641 | 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x14, | |
642 | 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x15, | |
643 | 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x14, | |
644 | 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x90, 0x16, | |
645 | 0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x23, 0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x24, | |
646 | 0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x23, 0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x25, | |
647 | 0x30, 0x31, 0x30, 0x32, 0x30, 0x31, 0x30, 0x33, 0x30, 0x31, 0x30, 0x32, 0x30, 0x31, 0x30, 0x34, | |
648 | 0x40, 0x41, 0x40, 0x42, 0x40, 0x41, 0x40, 0x43, 0x50, 0x51, 0x50, 0x52, 0x60, 0x61, 0x70, 0x78 | |
649 | }; | |
650 | ||
651 | /* hdlc_unpack | |
652 | * perform HDLC frame processing (bit unstuffing, flag detection, FCS calculation) | |
653 | * on a sequence of received data bytes (8 bits each, LSB first) | |
654 | * pass on successfully received, complete frames as SKBs via gigaset_rcv_skb | |
655 | * notify of errors via gigaset_rcv_error | |
656 | * tally frames, errors etc. in BC structure counters | |
657 | * parameters: | |
658 | * src received data | |
659 | * count number of received bytes | |
660 | * bcs receiving B channel structure | |
661 | */ | |
662 | static inline void hdlc_unpack(unsigned char *src, unsigned count, | |
784d5858 | 663 | struct bc_state *bcs) |
76bb4685 | 664 | { |
d48c7784 | 665 | struct bas_bc_state *ubc = bcs->hw.bas; |
76bb4685 HL |
666 | int inputstate; |
667 | unsigned seqlen, inbyte, inbits; | |
668 | ||
76bb4685 HL |
669 | /* load previous state: |
670 | * inputstate = set of flag bits: | |
671 | * - INS_flag_hunt: no complete opening flag received since connection setup or last abort | |
672 | * - INS_have_data: at least one complete data byte received since last flag | |
673 | * seqlen = number of consecutive '1' bits in last 7 input stream bits (0..7) | |
674 | * inbyte = accumulated partial data byte (if !INS_flag_hunt) | |
675 | * inbits = number of valid bits in inbyte, starting at LSB (0..6) | |
676 | */ | |
677 | inputstate = bcs->inputstate; | |
678 | seqlen = ubc->seqlen; | |
679 | inbyte = ubc->inbyte; | |
680 | inbits = ubc->inbits; | |
681 | ||
682 | /* bit unstuffing a byte a time | |
683 | * Take your time to understand this; it's straightforward but tedious. | |
684 | * The "bitcounts" lookup table is used to speed up the counting of | |
685 | * leading and trailing '1' bits. | |
686 | */ | |
687 | while (count--) { | |
688 | unsigned char c = *src++; | |
689 | unsigned char tabentry = bitcounts[c]; | |
690 | unsigned lead1 = tabentry & 0x0f; | |
691 | unsigned trail1 = (tabentry >> 4) & 0x0f; | |
692 | ||
693 | seqlen += lead1; | |
694 | ||
695 | if (unlikely(inputstate & INS_flag_hunt)) { | |
696 | if (c == PPP_FLAG) { | |
697 | /* flag-in-one */ | |
698 | inputstate &= ~(INS_flag_hunt | INS_have_data); | |
699 | inbyte = 0; | |
700 | inbits = 0; | |
701 | } else if (seqlen == 6 && trail1 != 7) { | |
702 | /* flag completed & not followed by abort */ | |
703 | inputstate &= ~(INS_flag_hunt | INS_have_data); | |
704 | inbyte = c >> (lead1 + 1); | |
705 | inbits = 7 - lead1; | |
706 | if (trail1 >= 8) { | |
707 | /* interior stuffing: omitting the MSB handles most cases */ | |
708 | inbits--; | |
709 | /* correct the incorrectly handled cases individually */ | |
710 | switch (c) { | |
711 | case 0xbe: | |
712 | inbyte = 0x3f; | |
713 | break; | |
714 | } | |
715 | } | |
716 | } | |
717 | /* else: continue flag-hunting */ | |
718 | } else if (likely(seqlen < 5 && trail1 < 7)) { | |
719 | /* streamlined case: 8 data bits, no stuffing */ | |
720 | inbyte |= c << inbits; | |
721 | hdlc_putbyte(inbyte & 0xff, bcs); | |
722 | inputstate |= INS_have_data; | |
723 | inbyte >>= 8; | |
724 | /* inbits unchanged */ | |
725 | } else if (likely(seqlen == 6 && inbits == 7 - lead1 && | |
726 | trail1 + 1 == inbits && | |
727 | !(inputstate & INS_have_data))) { | |
728 | /* streamlined case: flag idle - state unchanged */ | |
729 | } else if (unlikely(seqlen > 6)) { | |
730 | /* abort sequence */ | |
731 | ubc->aborts++; | |
732 | hdlc_flush(bcs); | |
733 | inputstate |= INS_flag_hunt; | |
734 | } else if (seqlen == 6) { | |
735 | /* closing flag, including (6 - lead1) '1's and one '0' from inbits */ | |
736 | if (inbits > 7 - lead1) { | |
737 | hdlc_frag(bcs, inbits + lead1 - 7); | |
738 | inputstate &= ~INS_have_data; | |
739 | } else { | |
740 | if (inbits < 7 - lead1) | |
741 | ubc->stolen0s ++; | |
742 | if (inputstate & INS_have_data) { | |
743 | hdlc_done(bcs); | |
744 | inputstate &= ~INS_have_data; | |
745 | } | |
746 | } | |
747 | ||
748 | if (c == PPP_FLAG) { | |
749 | /* complete flag, LSB overlaps preceding flag */ | |
750 | ubc->shared0s ++; | |
751 | inbits = 0; | |
752 | inbyte = 0; | |
753 | } else if (trail1 != 7) { | |
754 | /* remaining bits */ | |
755 | inbyte = c >> (lead1 + 1); | |
756 | inbits = 7 - lead1; | |
757 | if (trail1 >= 8) { | |
758 | /* interior stuffing: omitting the MSB handles most cases */ | |
759 | inbits--; | |
760 | /* correct the incorrectly handled cases individually */ | |
761 | switch (c) { | |
762 | case 0xbe: | |
763 | inbyte = 0x3f; | |
764 | break; | |
765 | } | |
766 | } | |
767 | } else { | |
768 | /* abort sequence follows, skb already empty anyway */ | |
769 | ubc->aborts++; | |
770 | inputstate |= INS_flag_hunt; | |
771 | } | |
772 | } else { /* (seqlen < 6) && (seqlen == 5 || trail1 >= 7) */ | |
773 | ||
774 | if (c == PPP_FLAG) { | |
775 | /* complete flag */ | |
776 | if (seqlen == 5) | |
777 | ubc->stolen0s++; | |
778 | if (inbits) { | |
779 | hdlc_frag(bcs, inbits); | |
780 | inbits = 0; | |
781 | inbyte = 0; | |
782 | } else if (inputstate & INS_have_data) | |
783 | hdlc_done(bcs); | |
784 | inputstate &= ~INS_have_data; | |
785 | } else if (trail1 == 7) { | |
786 | /* abort sequence */ | |
787 | ubc->aborts++; | |
788 | hdlc_flush(bcs); | |
789 | inputstate |= INS_flag_hunt; | |
790 | } else { | |
791 | /* stuffed data */ | |
792 | if (trail1 < 7) { /* => seqlen == 5 */ | |
793 | /* stuff bit at position lead1, no interior stuffing */ | |
794 | unsigned char mask = (1 << lead1) - 1; | |
795 | c = (c & mask) | ((c & ~mask) >> 1); | |
796 | inbyte |= c << inbits; | |
797 | inbits += 7; | |
798 | } else if (seqlen < 5) { /* trail1 >= 8 */ | |
799 | /* interior stuffing: omitting the MSB handles most cases */ | |
800 | /* correct the incorrectly handled cases individually */ | |
801 | switch (c) { | |
802 | case 0xbe: | |
803 | c = 0x7e; | |
804 | break; | |
805 | } | |
806 | inbyte |= c << inbits; | |
807 | inbits += 7; | |
808 | } else { /* seqlen == 5 && trail1 >= 8 */ | |
809 | ||
810 | /* stuff bit at lead1 *and* interior stuffing */ | |
811 | switch (c) { /* unstuff individually */ | |
812 | case 0x7d: | |
813 | c = 0x3f; | |
814 | break; | |
815 | case 0xbe: | |
816 | c = 0x3f; | |
817 | break; | |
818 | case 0x3e: | |
819 | c = 0x1f; | |
820 | break; | |
821 | case 0x7c: | |
822 | c = 0x3e; | |
823 | break; | |
824 | } | |
825 | inbyte |= c << inbits; | |
826 | inbits += 6; | |
827 | } | |
828 | if (inbits >= 8) { | |
829 | inbits -= 8; | |
830 | hdlc_putbyte(inbyte & 0xff, bcs); | |
831 | inputstate |= INS_have_data; | |
832 | inbyte >>= 8; | |
833 | } | |
834 | } | |
835 | } | |
836 | seqlen = trail1 & 7; | |
837 | } | |
838 | ||
839 | /* save new state */ | |
840 | bcs->inputstate = inputstate; | |
841 | ubc->seqlen = seqlen; | |
842 | ubc->inbyte = inbyte; | |
843 | ubc->inbits = inbits; | |
844 | } | |
845 | ||
846 | /* trans_receive | |
847 | * pass on received USB frame transparently as SKB via gigaset_rcv_skb | |
848 | * invert bytes | |
849 | * tally frames, errors etc. in BC structure counters | |
850 | * parameters: | |
851 | * src received data | |
852 | * count number of received bytes | |
853 | * bcs receiving B channel structure | |
854 | */ | |
855 | static inline void trans_receive(unsigned char *src, unsigned count, | |
784d5858 | 856 | struct bc_state *bcs) |
76bb4685 HL |
857 | { |
858 | struct sk_buff *skb; | |
859 | int dobytes; | |
860 | unsigned char *dst; | |
861 | ||
862 | if (unlikely(bcs->ignore)) { | |
863 | bcs->ignore--; | |
864 | hdlc_flush(bcs); | |
865 | return; | |
866 | } | |
867 | if (unlikely((skb = bcs->skb) == NULL)) { | |
868 | bcs->skb = skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN); | |
869 | if (!skb) { | |
784d5858 | 870 | dev_err(bcs->cs->dev, "could not allocate skb\n"); |
76bb4685 HL |
871 | return; |
872 | } | |
873 | skb_reserve(skb, HW_HDR_LEN); | |
874 | } | |
875 | bcs->hw.bas->goodbytes += skb->len; | |
876 | dobytes = TRANSBUFSIZE - skb->len; | |
877 | while (count > 0) { | |
878 | dst = skb_put(skb, count < dobytes ? count : dobytes); | |
879 | while (count > 0 && dobytes > 0) { | |
17b3cff0 | 880 | *dst++ = bitrev8(*src++); |
76bb4685 HL |
881 | count--; |
882 | dobytes--; | |
883 | } | |
884 | if (dobytes == 0) { | |
885 | gigaset_rcv_skb(skb, bcs->cs, bcs); | |
886 | bcs->skb = skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN); | |
887 | if (!skb) { | |
784d5858 TS |
888 | dev_err(bcs->cs->dev, |
889 | "could not allocate skb\n"); | |
76bb4685 HL |
890 | return; |
891 | } | |
892 | skb_reserve(bcs->skb, HW_HDR_LEN); | |
893 | dobytes = TRANSBUFSIZE; | |
894 | } | |
895 | } | |
896 | } | |
897 | ||
898 | void gigaset_isoc_receive(unsigned char *src, unsigned count, struct bc_state *bcs) | |
899 | { | |
900 | switch (bcs->proto2) { | |
901 | case ISDN_PROTO_L2_HDLC: | |
902 | hdlc_unpack(src, count, bcs); | |
903 | break; | |
904 | default: /* assume transparent */ | |
905 | trans_receive(src, count, bcs); | |
906 | } | |
907 | } | |
908 | ||
909 | /* == data input =========================================================== */ | |
910 | ||
911 | static void cmd_loop(unsigned char *src, int numbytes, struct inbuf_t *inbuf) | |
912 | { | |
913 | struct cardstate *cs = inbuf->cs; | |
914 | unsigned cbytes = cs->cbytes; | |
915 | ||
916 | while (numbytes--) { | |
917 | /* copy next character, check for end of line */ | |
918 | switch (cs->respdata[cbytes] = *src++) { | |
919 | case '\r': | |
920 | case '\n': | |
921 | /* end of line */ | |
784d5858 TS |
922 | gig_dbg(DEBUG_TRANSCMD, "%s: End of Command (%d Bytes)", |
923 | __func__, cbytes); | |
92ba0ee2 TS |
924 | if (cbytes >= MAX_RESP_SIZE - 1) |
925 | dev_warn(cs->dev, "response too large\n"); | |
76bb4685 HL |
926 | cs->cbytes = cbytes; |
927 | gigaset_handle_modem_response(cs); | |
928 | cbytes = 0; | |
929 | break; | |
930 | default: | |
931 | /* advance in line buffer, checking for overflow */ | |
932 | if (cbytes < MAX_RESP_SIZE - 1) | |
933 | cbytes++; | |
76bb4685 HL |
934 | } |
935 | } | |
936 | ||
937 | /* save state */ | |
938 | cs->cbytes = cbytes; | |
939 | } | |
940 | ||
941 | ||
942 | /* process a block of data received through the control channel | |
943 | */ | |
944 | void gigaset_isoc_input(struct inbuf_t *inbuf) | |
945 | { | |
946 | struct cardstate *cs = inbuf->cs; | |
947 | unsigned tail, head, numbytes; | |
948 | unsigned char *src; | |
949 | ||
9d4bee2b TS |
950 | head = inbuf->head; |
951 | while (head != (tail = inbuf->tail)) { | |
784d5858 | 952 | gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail); |
76bb4685 HL |
953 | if (head > tail) |
954 | tail = RBUFSIZE; | |
955 | src = inbuf->data + head; | |
956 | numbytes = tail - head; | |
784d5858 | 957 | gig_dbg(DEBUG_INTR, "processing %u bytes", numbytes); |
76bb4685 | 958 | |
9d4bee2b | 959 | if (cs->mstate == MS_LOCKED) { |
76bb4685 | 960 | gigaset_dbg_buffer(DEBUG_LOCKCMD, "received response", |
01371500 | 961 | numbytes, src); |
76bb4685 HL |
962 | gigaset_if_receive(inbuf->cs, src, numbytes); |
963 | } else { | |
964 | gigaset_dbg_buffer(DEBUG_CMD, "received response", | |
01371500 | 965 | numbytes, src); |
76bb4685 HL |
966 | cmd_loop(src, numbytes, inbuf); |
967 | } | |
968 | ||
969 | head += numbytes; | |
970 | if (head == RBUFSIZE) | |
971 | head = 0; | |
784d5858 | 972 | gig_dbg(DEBUG_INTR, "setting head to %u", head); |
9d4bee2b | 973 | inbuf->head = head; |
76bb4685 HL |
974 | } |
975 | } | |
976 | ||
977 | ||
978 | /* == data output ========================================================== */ | |
979 | ||
980 | /* gigaset_send_skb | |
981 | * called by common.c to queue an skb for sending | |
982 | * and start transmission if necessary | |
983 | * parameters: | |
984 | * B Channel control structure | |
985 | * skb | |
986 | * return value: | |
987 | * number of bytes accepted for sending | |
988 | * (skb->len if ok, 0 if out of buffer space) | |
989 | * or error code (< 0, eg. -EINVAL) | |
990 | */ | |
991 | int gigaset_isoc_send_skb(struct bc_state *bcs, struct sk_buff *skb) | |
992 | { | |
d48c7784 | 993 | int len = skb->len; |
69049cc8 | 994 | unsigned long flags; |
76bb4685 | 995 | |
73a88814 TS |
996 | spin_lock_irqsave(&bcs->cs->lock, flags); |
997 | if (!bcs->cs->connected) { | |
998 | spin_unlock_irqrestore(&bcs->cs->lock, flags); | |
999 | return -ENODEV; | |
1000 | } | |
1001 | ||
76bb4685 | 1002 | skb_queue_tail(&bcs->squeue, skb); |
784d5858 TS |
1003 | gig_dbg(DEBUG_ISO, "%s: skb queued, qlen=%d", |
1004 | __func__, skb_queue_len(&bcs->squeue)); | |
76bb4685 HL |
1005 | |
1006 | /* tasklet submits URB if necessary */ | |
73a88814 | 1007 | tasklet_schedule(&bcs->hw.bas->sent_tasklet); |
69049cc8 | 1008 | spin_unlock_irqrestore(&bcs->cs->lock, flags); |
76bb4685 HL |
1009 | |
1010 | return len; /* ok so far */ | |
1011 | } |