Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/drivers/isdn/i4l/isdn_v110.c b/drivers/isdn/i4l/isdn_v110.c
new file mode 100644
index 0000000..f47f2b9
--- /dev/null
+++ b/drivers/isdn/i4l/isdn_v110.c
@@ -0,0 +1,617 @@
+/* $Id: isdn_v110.c,v 1.1.2.2 2004/01/12 22:37:19 keil Exp $
+ *
+ * Linux ISDN subsystem, V.110 related functions (linklevel).
+ *
+ * Copyright by Thomas Pfeiffer (pfeiffer@pds.de)
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+
+#include <linux/isdn.h>
+#include "isdn_v110.h"
+
+#undef ISDN_V110_DEBUG
+
+char *isdn_v110_revision = "$Revision: 1.1.2.2 $";
+
+#define V110_38400 255
+#define V110_19200  15
+#define V110_9600    3
+
+/* 
+ * The following data are precoded matrices, online and offline matrix 
+ * for 9600, 19200 und 38400, respectively
+ */
+static unsigned char V110_OnMatrix_9600[] =
+{0xfc, 0xfc, 0xfc, 0xfc, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff,
+ 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd,
+ 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff,
+ 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd};
+
+static unsigned char V110_OffMatrix_9600[] =
+{0xfc, 0xfc, 0xfc, 0xfc, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+
+static unsigned char V110_OnMatrix_19200[] =
+{0xf0, 0xf0, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7,
+ 0xfd, 0xff, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7};
+
+static unsigned char V110_OffMatrix_19200[] =
+{0xf0, 0xf0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+
+static unsigned char V110_OnMatrix_38400[] =
+{0x00, 0x7f, 0x7f, 0x7f, 0x7f, 0xfd, 0x7f, 0x7f, 0x7f, 0x7f};
+
+static unsigned char V110_OffMatrix_38400[] =
+{0x00, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xff};
+
+/* 
+ * FlipBits reorders sequences of keylen bits in one byte.
+ * E.g. source order 7654321 will be converted to 45670123 when keylen = 4,
+ * and to 67452301 when keylen = 2. This is necessary because ordering on
+ * the isdn line is the other way.
+ */
+static __inline unsigned char
+FlipBits(unsigned char c, int keylen)
+{
+	unsigned char b = c;
+	unsigned char bit = 128;
+	int i;
+	int j;
+	int hunks = (8 / keylen);
+
+	c = 0;
+	for (i = 0; i < hunks; i++) {
+		for (j = 0; j < keylen; j++) {
+			if (b & (bit >> j))
+				c |= bit >> (keylen - j - 1);
+		}
+		bit >>= keylen;
+	}
+	return c;
+}
+
+
+/* isdn_v110_open allocates and initializes private V.110 data
+ * structures and returns a pointer to these.
+ */
+static isdn_v110_stream *
+isdn_v110_open(unsigned char key, int hdrlen, int maxsize)
+{
+	int i;
+	isdn_v110_stream *v;
+
+	if ((v = kmalloc(sizeof(isdn_v110_stream), GFP_ATOMIC)) == NULL)
+		return NULL;
+	memset(v, 0, sizeof(isdn_v110_stream));
+	v->key = key;
+	v->nbits = 0;
+	for (i = 0; key & (1 << i); i++)
+		v->nbits++;
+
+	v->nbytes = 8 / v->nbits;
+	v->decodelen = 0;
+
+	switch (key) {
+		case V110_38400:
+			v->OnlineFrame = V110_OnMatrix_38400;
+			v->OfflineFrame = V110_OffMatrix_38400;
+			break;
+		case V110_19200:
+			v->OnlineFrame = V110_OnMatrix_19200;
+			v->OfflineFrame = V110_OffMatrix_19200;
+			break;
+		default:
+			v->OnlineFrame = V110_OnMatrix_9600;
+			v->OfflineFrame = V110_OffMatrix_9600;
+			break;
+	}
+	v->framelen = v->nbytes * 10;
+	v->SyncInit = 5;
+	v->introducer = 0;
+	v->dbit = 1;
+	v->b = 0;
+	v->skbres = hdrlen;
+	v->maxsize = maxsize - hdrlen;
+	if ((v->encodebuf = kmalloc(maxsize, GFP_ATOMIC)) == NULL) {
+		kfree(v);
+		return NULL;
+	}
+	return v;
+}
+
+/* isdn_v110_close frees private V.110 data structures */
+void
+isdn_v110_close(isdn_v110_stream * v)
+{
+	if (v == NULL)
+		return;
+#ifdef ISDN_V110_DEBUG
+	printk(KERN_DEBUG "v110 close\n");
+#endif
+	kfree(v->encodebuf);
+	kfree(v);
+}
+
+
+/* 
+ * ValidHeaderBytes return the number of valid bytes in v->decodebuf 
+ */
+static int
+ValidHeaderBytes(isdn_v110_stream * v)
+{
+	int i;
+	for (i = 0; (i < v->decodelen) && (i < v->nbytes); i++)
+		if ((v->decodebuf[i] & v->key) != 0)
+			break;
+	return i;
+}
+
+/* 
+ * SyncHeader moves the decodebuf ptr to the next valid header 
+ */
+static void
+SyncHeader(isdn_v110_stream * v)
+{
+	unsigned char *rbuf = v->decodebuf;
+	int len = v->decodelen;
+
+	if (len == 0)
+		return;
+	for (rbuf++, len--; len > 0; len--, rbuf++)	/* such den SyncHeader in buf ! */
+		if ((*rbuf & v->key) == 0)	/* erstes byte gefunden ?       */
+			break;  /* jupp!                        */
+	if (len)
+		memcpy(v->decodebuf, rbuf, len);
+
+	v->decodelen = len;
+#ifdef ISDN_V110_DEBUG
+	printk(KERN_DEBUG "isdn_v110: Header resync\n");
+#endif
+}
+
+/* DecodeMatrix takes n (n>=1) matrices (v110 frames, 10 bytes) where
+   len is the number of matrix-lines. len must be a multiple of 10, i.e.
+   only complete matices must be given.
+   From these, netto data is extracted and returned in buf. The return-value
+   is the bytecount of the decoded data.
+ */
+static int
+DecodeMatrix(isdn_v110_stream * v, unsigned char *m, int len, unsigned char *buf)
+{
+	int line = 0;
+	int buflen = 0;
+	int mbit = 64;
+	int introducer = v->introducer;
+	int dbit = v->dbit;
+	unsigned char b = v->b;
+
+	while (line < len) {    /* Are we done with all lines of the matrix? */
+		if ((line % 10) == 0) {	/* the 0. line of the matrix is always 0 ! */
+			if (m[line] != 0x00) {	/* not 0 ? -> error! */
+#ifdef ISDN_V110_DEBUG
+				printk(KERN_DEBUG "isdn_v110: DecodeMatrix, V110 Bad Header\n");
+				/* returning now is not the right thing, though :-( */
+#endif
+			} 
+			line++; /* next line of matrix */
+			continue;
+		} else if ((line % 10) == 5) {	/* in line 5 there's only e-bits ! */
+			if ((m[line] & 0x70) != 0x30) {	/* 011 has to be at the beginning! */
+#ifdef ISDN_V110_DEBUG
+				printk(KERN_DEBUG "isdn_v110: DecodeMatrix, V110 Bad 5th line\n");
+				/* returning now is not the right thing, though :-( */
+#endif
+			}
+			line++; /* next line */
+			continue;
+		} else if (!introducer) {	/* every byte starts with 10 (stopbit, startbit) */
+			introducer = (m[line] & mbit) ? 0 : 1;	/* current bit of the matrix */
+		      next_byte:
+			if (mbit > 2) {	/* was it the last bit in this line ? */
+				mbit >>= 1;	/* no -> take next */
+				continue;
+			}       /* otherwise start with leftmost bit in the next line */
+			mbit = 64;
+			line++;
+			continue;
+		} else {        /* otherwise we need to set a data bit */
+			if (m[line] & mbit)	/* was that bit set in the matrix ? */
+				b |= dbit;	/* yes -> set it in the data byte */
+			else
+				b &= dbit - 1;	/* no -> clear it in the data byte */
+			if (dbit < 128)	/* is that data byte done ? */
+				dbit <<= 1;	/* no, got the next bit */
+			else {  /* data byte is done */
+				buf[buflen++] = b;	/* copy byte into the output buffer */
+				introducer = b = 0;	/* init of the intro sequence and of the data byte */
+				dbit = 1;	/* next we look for the 0th bit */
+			}
+			goto next_byte;	/* look for next bit in the matrix */
+		}
+	}
+	v->introducer = introducer;
+	v->dbit = dbit;
+	v->b = b;
+	return buflen;          /* return number of bytes in the output buffer */
+}
+
+/* 
+ * DecodeStream receives V.110 coded data from the input stream. It recovers the 
+ * original frames.
+ * The input stream doesn't need to be framed
+ */
+struct sk_buff *
+isdn_v110_decode(isdn_v110_stream * v, struct sk_buff *skb)
+{
+	int i;
+	int j;
+	int len;
+	unsigned char *v110_buf;
+	unsigned char *rbuf;
+
+	if (!skb) {
+		printk(KERN_WARNING "isdn_v110_decode called with NULL skb!\n");
+		return NULL;
+	}
+	rbuf = skb->data;
+	len = skb->len;
+	if (v == NULL) {
+		/* invalid handle, no chance to proceed */
+		printk(KERN_WARNING "isdn_v110_decode called with NULL stream!\n");
+		dev_kfree_skb(skb);
+		return NULL;
+	}
+	if (v->decodelen == 0)  /* cache empty?               */
+		for (; len > 0; len--, rbuf++)	/* scan for SyncHeader in buf */
+			if ((*rbuf & v->key) == 0)
+				break;	/* found first byte           */
+	if (len == 0) {
+		dev_kfree_skb(skb);
+		return NULL;
+	}
+	/* copy new data to decode-buffer */
+	memcpy(&(v->decodebuf[v->decodelen]), rbuf, len);
+	v->decodelen += len;
+      ReSync:
+	if (v->decodelen < v->nbytes) {	/* got a new header ? */
+		dev_kfree_skb(skb);
+		return NULL;    /* no, try later      */
+	}
+	if (ValidHeaderBytes(v) != v->nbytes) {	/* is that a valid header? */
+		SyncHeader(v);  /* no -> look for header */
+		goto ReSync;
+	}
+	len = (v->decodelen - (v->decodelen % (10 * v->nbytes))) / v->nbytes;
+	if ((v110_buf = kmalloc(len, GFP_ATOMIC)) == NULL) {
+		printk(KERN_WARNING "isdn_v110_decode: Couldn't allocate v110_buf\n");
+		dev_kfree_skb(skb);
+		return NULL;
+	}
+	for (i = 0; i < len; i++) {
+		v110_buf[i] = 0;
+		for (j = 0; j < v->nbytes; j++)
+			v110_buf[i] |= (v->decodebuf[(i * v->nbytes) + j] & v->key) << (8 - ((j + 1) * v->nbits));
+		v110_buf[i] = FlipBits(v110_buf[i], v->nbits);
+	}
+	v->decodelen = (v->decodelen % (10 * v->nbytes));
+	memcpy(v->decodebuf, &(v->decodebuf[len * v->nbytes]), v->decodelen);
+
+	skb_trim(skb, DecodeMatrix(v, v110_buf, len, skb->data));
+	kfree(v110_buf);
+	if (skb->len)
+		return skb;
+	else {
+		kfree_skb(skb);
+		return NULL;
+	}
+}
+
+/* EncodeMatrix takes input data in buf, len is the bytecount.
+   Data is encoded into v110 frames in m. Return value is the number of
+   matrix-lines generated.
+ */
+static int
+EncodeMatrix(unsigned char *buf, int len, unsigned char *m, int mlen)
+{
+	int line = 0;
+	int i = 0;
+	int mbit = 128;
+	int dbit = 1;
+	int introducer = 3;
+	int ibit[] = {0, 1, 1};
+
+	while ((i < len) && (line < mlen)) {	/* while we still have input data */
+		switch (line % 10) {	/* in which line of the matrix are we? */
+			case 0:
+				m[line++] = 0x00;	/* line 0 is always 0 */
+				mbit = 128;	/* go on with the 7th bit */
+				break;
+			case 5:
+				m[line++] = 0xbf;	/* line 5 is always 10111111 */
+				mbit = 128;	/* go on with the 7th bit */
+				break;
+		}
+		if (line >= mlen) {
+			printk(KERN_WARNING "isdn_v110 (EncodeMatrix): buffer full!\n");
+			return line;
+		}
+	next_bit:
+		switch (mbit) { /* leftmost or rightmost bit ? */
+			case 1:
+				line++;	/* rightmost -> go to next line */
+				if (line >= mlen) {
+					printk(KERN_WARNING "isdn_v110 (EncodeMatrix): buffer full!\n");
+					return line;
+				}
+			case 128:
+				m[line] = 128;	/* leftmost -> set byte to 1000000 */
+				mbit = 64;	/* current bit in the matrix line */
+				continue;
+		}
+		if (introducer) {	/* set 110 sequence ? */
+			introducer--;	/* set on digit less */
+			m[line] |= ibit[introducer] ? mbit : 0;	/* set corresponding bit */
+			mbit >>= 1;	/* bit of matrix line  >> 1 */
+			goto next_bit;	/* and go on there */
+		}               /* else push data bits into the matrix! */
+		m[line] |= (buf[i] & dbit) ? mbit : 0;	/* set data bit in matrix */
+		if (dbit == 128) {	/* was it the last one? */
+			dbit = 1;	/* then go on with first bit of  */
+			i++;            /* next byte in input buffer */
+			if (i < len)	/* input buffer done ? */
+				introducer = 3;	/* no, write introducer 110 */
+			else {  /* input buffer done ! */
+				m[line] |= (mbit - 1) & 0xfe;	/* set remaining bits in line to 1 */
+				break;
+			}
+		} else          /* not the last data bit */
+			dbit <<= 1;	/* then go to next data bit */
+		mbit >>= 1;     /* go to next bit of matrix */
+		goto next_bit;
+
+	}
+	/* if necessary, generate remaining lines of the matrix... */
+	if ((line) && ((line + 10) < mlen))
+		switch (++line % 10) {
+			case 1:
+				m[line++] = 0xfe;
+			case 2:
+				m[line++] = 0xfe;
+			case 3:
+				m[line++] = 0xfe;
+			case 4:
+				m[line++] = 0xfe;
+			case 5:
+				m[line++] = 0xbf;
+			case 6:
+				m[line++] = 0xfe;
+			case 7:
+				m[line++] = 0xfe;
+			case 8:
+				m[line++] = 0xfe;
+			case 9:
+				m[line++] = 0xfe;
+		}
+	return line;            /* that's how many lines we have */
+}
+
+/*
+ * Build a sync frame.
+ */
+static struct sk_buff *
+isdn_v110_sync(isdn_v110_stream *v)
+{
+	struct sk_buff *skb;
+
+	if (v == NULL) {
+		/* invalid handle, no chance to proceed */
+		printk(KERN_WARNING "isdn_v110_sync called with NULL stream!\n");
+		return NULL;
+	}
+	if ((skb = dev_alloc_skb(v->framelen + v->skbres))) {
+		skb_reserve(skb, v->skbres);
+		memcpy(skb_put(skb, v->framelen), v->OfflineFrame, v->framelen);
+	}
+	return skb;
+}
+
+/*
+ * Build an idle frame.
+ */
+static struct sk_buff *
+isdn_v110_idle(isdn_v110_stream *v)
+{
+	struct sk_buff *skb;
+
+	if (v == NULL) {
+		/* invalid handle, no chance to proceed */
+		printk(KERN_WARNING "isdn_v110_sync called with NULL stream!\n");
+		return NULL;
+	}
+	if ((skb = dev_alloc_skb(v->framelen + v->skbres))) {
+		skb_reserve(skb, v->skbres);
+		memcpy(skb_put(skb, v->framelen), v->OnlineFrame, v->framelen);
+	}
+	return skb;
+}
+
+struct sk_buff *
+isdn_v110_encode(isdn_v110_stream * v, struct sk_buff *skb)
+{
+	int i;
+	int j;
+	int rlen;
+	int mlen;
+	int olen;
+	int size;
+	int sval1;
+	int sval2;
+	int nframes;
+	unsigned char *v110buf;
+	unsigned char *rbuf;
+	struct sk_buff *nskb;
+
+	if (v == NULL) {
+		/* invalid handle, no chance to proceed */
+		printk(KERN_WARNING "isdn_v110_encode called with NULL stream!\n");
+		return NULL;
+	}
+	if (!skb) {
+		/* invalid skb, no chance to proceed */
+		printk(KERN_WARNING "isdn_v110_encode called with NULL skb!\n");
+		return NULL;
+	}
+	rlen = skb->len;
+	nframes = (rlen + 3) / 4;
+	v110buf = v->encodebuf;
+	if ((nframes * 40) > v->maxsize) {
+		size = v->maxsize;
+		rlen = v->maxsize / 40;
+	} else
+		size = nframes * 40;
+	if (!(nskb = dev_alloc_skb(size + v->skbres + sizeof(int)))) {
+		printk(KERN_WARNING "isdn_v110_encode: Couldn't alloc skb\n");
+		return NULL;
+	}
+	skb_reserve(nskb, v->skbres + sizeof(int));
+	if (skb->len == 0) {
+		memcpy(skb_put(nskb, v->framelen), v->OnlineFrame, v->framelen);
+		*((int *)skb_push(nskb, sizeof(int))) = 0;
+		return nskb;
+	}
+	mlen = EncodeMatrix(skb->data, rlen, v110buf, size);
+	/* now distribute 2 or 4 bits each to the output stream! */
+	rbuf = skb_put(nskb, size);
+	olen = 0;
+	sval1 = 8 - v->nbits;
+	sval2 = v->key << sval1;
+	for (i = 0; i < mlen; i++) {
+		v110buf[i] = FlipBits(v110buf[i], v->nbits);
+		for (j = 0; j < v->nbytes; j++) {
+			if (size--)
+				*rbuf++ = ~v->key | (((v110buf[i] << (j * v->nbits)) & sval2) >> sval1);
+			else {
+				printk(KERN_WARNING "isdn_v110_encode: buffers full!\n");
+				goto buffer_full;
+			}
+			olen++;
+		}
+	}
+buffer_full:
+	skb_trim(nskb, olen);
+	*((int *)skb_push(nskb, sizeof(int))) = rlen;
+	return nskb;
+}
+
+int
+isdn_v110_stat_callback(int idx, isdn_ctrl * c)
+{
+	isdn_v110_stream *v = NULL;
+	int i;
+	int ret;
+
+	if (idx < 0)
+		return 0;
+	switch (c->command) {
+		case ISDN_STAT_BSENT:
+                        /* Keep the send-queue of the driver filled
+			 * with frames:
+			 * If number of outstanding frames < 3,
+			 * send down an Idle-Frame (or an Sync-Frame, if
+			 * v->SyncInit != 0). 
+			 */
+			if (!(v = dev->v110[idx]))
+				return 0;
+			atomic_inc(&dev->v110use[idx]);
+			for (i=0; i * v->framelen < c->parm.length; i++) {
+				if (v->skbidle > 0) {
+					v->skbidle--;
+					ret = 1;
+				} else {
+					if (v->skbuser > 0)
+						v->skbuser--;
+					ret = 0;
+				}
+			}
+			for (i = v->skbuser + v->skbidle; i < 2; i++) {
+				struct sk_buff *skb;
+				if (v->SyncInit > 0)
+					skb = isdn_v110_sync(v);
+				else
+					skb = isdn_v110_idle(v);
+				if (skb) {
+					if (dev->drv[c->driver]->interface->writebuf_skb(c->driver, c->arg, 1, skb) <= 0) {
+						dev_kfree_skb(skb);
+						break;
+					} else {
+						if (v->SyncInit)
+							v->SyncInit--;
+						v->skbidle++;
+					}
+				} else
+					break;
+			}
+			atomic_dec(&dev->v110use[idx]);
+			return ret;
+		case ISDN_STAT_DHUP:
+		case ISDN_STAT_BHUP:
+			while (1) {
+				atomic_inc(&dev->v110use[idx]);
+				if (atomic_dec_and_test(&dev->v110use[idx])) {
+					isdn_v110_close(dev->v110[idx]);
+					dev->v110[idx] = NULL;
+					break;
+				}
+				mdelay(1);
+			}
+			break;
+		case ISDN_STAT_BCONN:
+			if (dev->v110emu[idx] && (dev->v110[idx] == NULL)) {
+				int hdrlen = dev->drv[c->driver]->interface->hl_hdrlen;
+				int maxsize = dev->drv[c->driver]->interface->maxbufsize;
+				atomic_inc(&dev->v110use[idx]);
+				switch (dev->v110emu[idx]) {
+					case ISDN_PROTO_L2_V11096:
+						dev->v110[idx] = isdn_v110_open(V110_9600, hdrlen, maxsize);
+						break;
+					case ISDN_PROTO_L2_V11019:
+						dev->v110[idx] = isdn_v110_open(V110_19200, hdrlen, maxsize);
+						break;
+					case ISDN_PROTO_L2_V11038:
+						dev->v110[idx] = isdn_v110_open(V110_38400, hdrlen, maxsize);
+						break;
+					default:;
+				}
+				if ((v = dev->v110[idx])) {
+					while (v->SyncInit) {
+						struct sk_buff *skb = isdn_v110_sync(v);
+						if (dev->drv[c->driver]->interface->writebuf_skb(c->driver, c->arg, 1, skb) <= 0) {
+							dev_kfree_skb(skb);
+							/* Unable to send, try later */
+							break;
+						}
+						v->SyncInit--;
+						v->skbidle++;
+					}
+				} else
+					printk(KERN_WARNING "isdn_v110: Couldn't open stream for chan %d\n", idx);
+				atomic_dec(&dev->v110use[idx]);
+			}
+			break;
+		default:
+			return 0;
+	}
+	return 0;
+}