isdn: remove hisax driver

With the decline of ISDN, this seems to have become almost completely
obsolete, and even in the past years before that, almost all remaining
users appear to have used mISDN instead.

Birger Harzenetter noted that he is still using i4l/hisax to take
advantage of the 'divert' driver for call diversion, but otherwise uses
mISDN on the same hardware. This is a rare edge case as far as I
can tell, but we are still breaking an actively used work flow
(see https://xkcd.com/1172/).

We debated moving i4l/hisax to staging as an intermediate step, but as
he is not likely to change the setup, and that would just delay breaking
this use case.  The alternatives here are to stay on stable kernels
< 5.2, to create an external driver repository for isdn4linux, or to
add divert functionality to mISDN.

Cc: Birger Harzenetter <WIMPy@yeti.dk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 0 insertions, 294 deletions

diff --git a/drivers/isdn/hisax/hscx_irq.c b/drivers/isdn/hisax/hscx_irq.c
deleted file mode 100644
index 0d7e783c8bef..000000000000
--- a/drivers/isdn/hisax/hscx_irq.c
+++ /dev/null
@@ -1,294 +0,0 @@
-/* $Id: hscx_irq.c,v 1.18.2.3 2004/02/11 13:21:34 keil Exp $
- *
- * low level b-channel stuff for Siemens HSCX
- *
- * Author       Karsten Keil
- * Copyright    by Karsten Keil      <keil@isdn4linux.de>
- *
- * This software may be used and distributed according to the terms
- * of the GNU General Public License, incorporated herein by reference.
- *
- * This is an include file for fast inline IRQ stuff
- *
- */
-
-
-static inline void
-waitforCEC(struct IsdnCardState *cs, int hscx)
-{
-	int to = 50;
-
-	while ((READHSCX(cs, hscx, HSCX_STAR) & 0x04) && to) {
-		udelay(1);
-		to--;
-	}
-	if (!to)
-		printk(KERN_WARNING "HiSax: waitforCEC timeout\n");
-}
-
-
-static inline void
-waitforXFW(struct IsdnCardState *cs, int hscx)
-{
-	int to = 50;
-
-	while (((READHSCX(cs, hscx, HSCX_STAR) & 0x44) != 0x40) && to) {
-		udelay(1);
-		to--;
-	}
-	if (!to)
-		printk(KERN_WARNING "HiSax: waitforXFW timeout\n");
-}
-
-static inline void
-WriteHSCXCMDR(struct IsdnCardState *cs, int hscx, u_char data)
-{
-	waitforCEC(cs, hscx);
-	WRITEHSCX(cs, hscx, HSCX_CMDR, data);
-}
-
-
-
-static void
-hscx_empty_fifo(struct BCState *bcs, int count)
-{
-	u_char *ptr;
-	struct IsdnCardState *cs = bcs->cs;
-
-	if ((cs->debug & L1_DEB_HSCX) && !(cs->debug & L1_DEB_HSCX_FIFO))
-		debugl1(cs, "hscx_empty_fifo");
-
-	if (bcs->hw.hscx.rcvidx + count > HSCX_BUFMAX) {
-		if (cs->debug & L1_DEB_WARN)
-			debugl1(cs, "hscx_empty_fifo: incoming packet too large");
-		WriteHSCXCMDR(cs, bcs->hw.hscx.hscx, 0x80);
-		bcs->hw.hscx.rcvidx = 0;
-		return;
-	}
-	ptr = bcs->hw.hscx.rcvbuf + bcs->hw.hscx.rcvidx;
-	bcs->hw.hscx.rcvidx += count;
-	READHSCXFIFO(cs, bcs->hw.hscx.hscx, ptr, count);
-	WriteHSCXCMDR(cs, bcs->hw.hscx.hscx, 0x80);
-	if (cs->debug & L1_DEB_HSCX_FIFO) {
-		char *t = bcs->blog;
-
-		t += sprintf(t, "hscx_empty_fifo %c cnt %d",
-			     bcs->hw.hscx.hscx ? 'B' : 'A', count);
-		QuickHex(t, ptr, count);
-		debugl1(cs, "%s", bcs->blog);
-	}
-}
-
-static void
-hscx_fill_fifo(struct BCState *bcs)
-{
-	struct IsdnCardState *cs = bcs->cs;
-	int more, count;
-	int fifo_size = test_bit(HW_IPAC, &cs->HW_Flags) ? 64 : 32;
-	u_char *ptr;
-
-	if ((cs->debug & L1_DEB_HSCX) && !(cs->debug & L1_DEB_HSCX_FIFO))
-		debugl1(cs, "hscx_fill_fifo");
-
-	if (!bcs->tx_skb)
-		return;
-	if (bcs->tx_skb->len <= 0)
-		return;
-
-	more = (bcs->mode == L1_MODE_TRANS) ? 1 : 0;
-	if (bcs->tx_skb->len > fifo_size) {
-		more = !0;
-		count = fifo_size;
-	} else
-		count = bcs->tx_skb->len;
-
-	waitforXFW(cs, bcs->hw.hscx.hscx);
-	ptr = bcs->tx_skb->data;
-	skb_pull(bcs->tx_skb, count);
-	bcs->tx_cnt -= count;
-	bcs->hw.hscx.count += count;
-	WRITEHSCXFIFO(cs, bcs->hw.hscx.hscx, ptr, count);
-	WriteHSCXCMDR(cs, bcs->hw.hscx.hscx, more ? 0x8 : 0xa);
-	if (cs->debug & L1_DEB_HSCX_FIFO) {
-		char *t = bcs->blog;
-
-		t += sprintf(t, "hscx_fill_fifo %c cnt %d",
-			     bcs->hw.hscx.hscx ? 'B' : 'A', count);
-		QuickHex(t, ptr, count);
-		debugl1(cs, "%s", bcs->blog);
-	}
-}
-
-static void
-hscx_interrupt(struct IsdnCardState *cs, u_char val, u_char hscx)
-{
-	u_char r;
-	struct BCState *bcs = cs->bcs + hscx;
-	struct sk_buff *skb;
-	int fifo_size = test_bit(HW_IPAC, &cs->HW_Flags) ? 64 : 32;
-	int count;
-
-	if (!test_bit(BC_FLG_INIT, &bcs->Flag))
-		return;
-
-	if (val & 0x80) {	/* RME */
-		r = READHSCX(cs, hscx, HSCX_RSTA);
-		if ((r & 0xf0) != 0xa0) {
-			if (!(r & 0x80)) {
-				if (cs->debug & L1_DEB_WARN)
-					debugl1(cs, "HSCX invalid frame");
-#ifdef ERROR_STATISTIC
-				bcs->err_inv++;
-#endif
-			}
-			if ((r & 0x40) && bcs->mode) {
-				if (cs->debug & L1_DEB_WARN)
-					debugl1(cs, "HSCX RDO mode=%d",
-						bcs->mode);
-#ifdef ERROR_STATISTIC
-				bcs->err_rdo++;
-#endif
-			}
-			if (!(r & 0x20)) {
-				if (cs->debug & L1_DEB_WARN)
-					debugl1(cs, "HSCX CRC error");
-#ifdef ERROR_STATISTIC
-				bcs->err_crc++;
-#endif
-			}
-			WriteHSCXCMDR(cs, hscx, 0x80);
-		} else {
-			count = READHSCX(cs, hscx, HSCX_RBCL) & (
-				test_bit(HW_IPAC, &cs->HW_Flags) ? 0x3f : 0x1f);
-			if (count == 0)
-				count = fifo_size;
-			hscx_empty_fifo(bcs, count);
-			if ((count = bcs->hw.hscx.rcvidx - 1) > 0) {
-				if (cs->debug & L1_DEB_HSCX_FIFO)
-					debugl1(cs, "HX Frame %d", count);
-				if (!(skb = dev_alloc_skb(count)))
-					printk(KERN_WARNING "HSCX: receive out of memory\n");
-				else {
-					skb_put_data(skb, bcs->hw.hscx.rcvbuf,
-						     count);
-					skb_queue_tail(&bcs->rqueue, skb);
-				}
-			}
-		}
-		bcs->hw.hscx.rcvidx = 0;
-		schedule_event(bcs, B_RCVBUFREADY);
-	}
-	if (val & 0x40) {	/* RPF */
-		hscx_empty_fifo(bcs, fifo_size);
-		if (bcs->mode == L1_MODE_TRANS) {
-			/* receive audio data */
-			if (!(skb = dev_alloc_skb(fifo_size)))
-				printk(KERN_WARNING "HiSax: receive out of memory\n");
-			else {
-				skb_put_data(skb, bcs->hw.hscx.rcvbuf,
-					     fifo_size);
-				skb_queue_tail(&bcs->rqueue, skb);
-			}
-			bcs->hw.hscx.rcvidx = 0;
-			schedule_event(bcs, B_RCVBUFREADY);
-		}
-	}
-	if (val & 0x10) {	/* XPR */
-		if (bcs->tx_skb) {
-			if (bcs->tx_skb->len) {
-				hscx_fill_fifo(bcs);
-				return;
-			} else {
-				if (test_bit(FLG_LLI_L1WAKEUP, &bcs->st->lli.flag) &&
-				    (PACKET_NOACK != bcs->tx_skb->pkt_type)) {
-					u_long	flags;
-					spin_lock_irqsave(&bcs->aclock, flags);
-					bcs->ackcnt += bcs->hw.hscx.count;
-					spin_unlock_irqrestore(&bcs->aclock, flags);
-					schedule_event(bcs, B_ACKPENDING);
-				}
-				dev_kfree_skb_irq(bcs->tx_skb);
-				bcs->hw.hscx.count = 0;
-				bcs->tx_skb = NULL;
-			}
-		}
-		if ((bcs->tx_skb = skb_dequeue(&bcs->squeue))) {
-			bcs->hw.hscx.count = 0;
-			test_and_set_bit(BC_FLG_BUSY, &bcs->Flag);
-			hscx_fill_fifo(bcs);
-		} else {
-			test_and_clear_bit(BC_FLG_BUSY, &bcs->Flag);
-			schedule_event(bcs, B_XMTBUFREADY);
-		}
-	}
-}
-
-static void
-hscx_int_main(struct IsdnCardState *cs, u_char val)
-{
-
-	u_char exval;
-	struct BCState *bcs;
-
-	if (val & 0x01) {
-		bcs = cs->bcs + 1;
-		exval = READHSCX(cs, 1, HSCX_EXIR);
-		if (exval & 0x40) {
-			if (bcs->mode == 1)
-				hscx_fill_fifo(bcs);
-			else {
-#ifdef ERROR_STATISTIC
-				bcs->err_tx++;
-#endif
-				/* Here we lost an TX interrupt, so
-				 * restart transmitting the whole frame.
-				 */
-				if (bcs->tx_skb) {
-					skb_push(bcs->tx_skb, bcs->hw.hscx.count);
-					bcs->tx_cnt += bcs->hw.hscx.count;
-					bcs->hw.hscx.count = 0;
-				}
-				WriteHSCXCMDR(cs, bcs->hw.hscx.hscx, 0x01);
-				if (cs->debug & L1_DEB_WARN)
-					debugl1(cs, "HSCX B EXIR %x Lost TX", exval);
-			}
-		} else if (cs->debug & L1_DEB_HSCX)
-			debugl1(cs, "HSCX B EXIR %x", exval);
-	}
-	if (val & 0xf8) {
-		if (cs->debug & L1_DEB_HSCX)
-			debugl1(cs, "HSCX B interrupt %x", val);
-		hscx_interrupt(cs, val, 1);
-	}
-	if (val & 0x02) {
-		bcs = cs->bcs;
-		exval = READHSCX(cs, 0, HSCX_EXIR);
-		if (exval & 0x40) {
-			if (bcs->mode == L1_MODE_TRANS)
-				hscx_fill_fifo(bcs);
-			else {
-				/* Here we lost an TX interrupt, so
-				 * restart transmitting the whole frame.
-				 */
-#ifdef ERROR_STATISTIC
-				bcs->err_tx++;
-#endif
-				if (bcs->tx_skb) {
-					skb_push(bcs->tx_skb, bcs->hw.hscx.count);
-					bcs->tx_cnt += bcs->hw.hscx.count;
-					bcs->hw.hscx.count = 0;
-				}
-				WriteHSCXCMDR(cs, bcs->hw.hscx.hscx, 0x01);
-				if (cs->debug & L1_DEB_WARN)
-					debugl1(cs, "HSCX A EXIR %x Lost TX", exval);
-			}
-		} else if (cs->debug & L1_DEB_HSCX)
-			debugl1(cs, "HSCX A EXIR %x", exval);
-	}
-	if (val & 0x04) {
-		exval = READHSCX(cs, 0, HSCX_ISTA);
-		if (cs->debug & L1_DEB_HSCX)
-			debugl1(cs, "HSCX A interrupt %x", exval);
-		hscx_interrupt(cs, exval, 0);
-	}
-}