Add mISDN core files
[cascardo/linux.git] / drivers / isdn / mISDN / hwchannel.c
diff --git a/drivers/isdn/mISDN/hwchannel.c b/drivers/isdn/mISDN/hwchannel.c
new file mode 100644 (file)
index 0000000..2596fba
--- /dev/null
@@ -0,0 +1,365 @@
+/*
+ *
+ * Author      Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/mISDNhw.h>
+
+static void
+dchannel_bh(struct work_struct *ws)
+{
+       struct dchannel *dch  = container_of(ws, struct dchannel, workq);
+       struct sk_buff  *skb;
+       int             err;
+
+       if (test_and_clear_bit(FLG_RECVQUEUE, &dch->Flags)) {
+               while ((skb = skb_dequeue(&dch->rqueue))) {
+                       if (likely(dch->dev.D.peer)) {
+                               err = dch->dev.D.recv(dch->dev.D.peer, skb);
+                               if (err)
+                                       dev_kfree_skb(skb);
+                       } else
+                               dev_kfree_skb(skb);
+               }
+       }
+       if (test_and_clear_bit(FLG_PHCHANGE, &dch->Flags)) {
+               if (dch->phfunc)
+                       dch->phfunc(dch);
+       }
+}
+
+static void
+bchannel_bh(struct work_struct *ws)
+{
+       struct bchannel *bch  = container_of(ws, struct bchannel, workq);
+       struct sk_buff  *skb;
+       int             err;
+
+       if (test_and_clear_bit(FLG_RECVQUEUE, &bch->Flags)) {
+               while ((skb = skb_dequeue(&bch->rqueue))) {
+                       if (bch->rcount >= 64)
+                               printk(KERN_WARNING "B-channel %p receive "
+                                       "queue if full, but empties...\n", bch);
+                       bch->rcount--;
+                       if (likely(bch->ch.peer)) {
+                               err = bch->ch.recv(bch->ch.peer, skb);
+                               if (err)
+                                       dev_kfree_skb(skb);
+                       } else
+                               dev_kfree_skb(skb);
+               }
+       }
+}
+
+int
+mISDN_initdchannel(struct dchannel *ch, int maxlen, void *phf)
+{
+       test_and_set_bit(FLG_HDLC, &ch->Flags);
+       ch->maxlen = maxlen;
+       ch->hw = NULL;
+       ch->rx_skb = NULL;
+       ch->tx_skb = NULL;
+       ch->tx_idx = 0;
+       ch->phfunc = phf;
+       skb_queue_head_init(&ch->squeue);
+       skb_queue_head_init(&ch->rqueue);
+       INIT_LIST_HEAD(&ch->dev.bchannels);
+       INIT_WORK(&ch->workq, dchannel_bh);
+       return 0;
+}
+EXPORT_SYMBOL(mISDN_initdchannel);
+
+int
+mISDN_initbchannel(struct bchannel *ch, int maxlen)
+{
+       ch->Flags = 0;
+       ch->maxlen = maxlen;
+       ch->hw = NULL;
+       ch->rx_skb = NULL;
+       ch->tx_skb = NULL;
+       ch->tx_idx = 0;
+       skb_queue_head_init(&ch->rqueue);
+       ch->rcount = 0;
+       ch->next_skb = NULL;
+       INIT_WORK(&ch->workq, bchannel_bh);
+       return 0;
+}
+EXPORT_SYMBOL(mISDN_initbchannel);
+
+int
+mISDN_freedchannel(struct dchannel *ch)
+{
+       if (ch->tx_skb) {
+               dev_kfree_skb(ch->tx_skb);
+               ch->tx_skb = NULL;
+       }
+       if (ch->rx_skb) {
+               dev_kfree_skb(ch->rx_skb);
+               ch->rx_skb = NULL;
+       }
+       skb_queue_purge(&ch->squeue);
+       skb_queue_purge(&ch->rqueue);
+       flush_scheduled_work();
+       return 0;
+}
+EXPORT_SYMBOL(mISDN_freedchannel);
+
+int
+mISDN_freebchannel(struct bchannel *ch)
+{
+       if (ch->tx_skb) {
+               dev_kfree_skb(ch->tx_skb);
+               ch->tx_skb = NULL;
+       }
+       if (ch->rx_skb) {
+               dev_kfree_skb(ch->rx_skb);
+               ch->rx_skb = NULL;
+       }
+       if (ch->next_skb) {
+               dev_kfree_skb(ch->next_skb);
+               ch->next_skb = NULL;
+       }
+       skb_queue_purge(&ch->rqueue);
+       ch->rcount = 0;
+       flush_scheduled_work();
+       return 0;
+}
+EXPORT_SYMBOL(mISDN_freebchannel);
+
+static inline u_int
+get_sapi_tei(u_char *p)
+{
+       u_int   sapi, tei;
+
+       sapi = *p >> 2;
+       tei = p[1] >> 1;
+       return sapi | (tei << 8);
+}
+
+void
+recv_Dchannel(struct dchannel *dch)
+{
+       struct mISDNhead *hh;
+
+       if (dch->rx_skb->len < 2) { /* at least 2 for sapi / tei */
+               dev_kfree_skb(dch->rx_skb);
+               dch->rx_skb = NULL;
+               return;
+       }
+       hh = mISDN_HEAD_P(dch->rx_skb);
+       hh->prim = PH_DATA_IND;
+       hh->id = get_sapi_tei(dch->rx_skb->data);
+       skb_queue_tail(&dch->rqueue, dch->rx_skb);
+       dch->rx_skb = NULL;
+       schedule_event(dch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Dchannel);
+
+void
+recv_Bchannel(struct bchannel *bch)
+{
+       struct mISDNhead *hh;
+
+       hh = mISDN_HEAD_P(bch->rx_skb);
+       hh->prim = PH_DATA_IND;
+       hh->id = MISDN_ID_ANY;
+       if (bch->rcount >= 64) {
+               dev_kfree_skb(bch->rx_skb);
+               bch->rx_skb = NULL;
+               return;
+       }
+       bch->rcount++;
+       skb_queue_tail(&bch->rqueue, bch->rx_skb);
+       bch->rx_skb = NULL;
+       schedule_event(bch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Bchannel);
+
+void
+recv_Dchannel_skb(struct dchannel *dch, struct sk_buff *skb)
+{
+       skb_queue_tail(&dch->rqueue, skb);
+       schedule_event(dch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Dchannel_skb);
+
+void
+recv_Bchannel_skb(struct bchannel *bch, struct sk_buff *skb)
+{
+       if (bch->rcount >= 64) {
+               dev_kfree_skb(skb);
+               return;
+       }
+       bch->rcount++;
+       skb_queue_tail(&bch->rqueue, skb);
+       schedule_event(bch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Bchannel_skb);
+
+static void
+confirm_Dsend(struct dchannel *dch)
+{
+       struct sk_buff  *skb;
+
+       skb = _alloc_mISDN_skb(PH_DATA_CNF, mISDN_HEAD_ID(dch->tx_skb),
+           0, NULL, GFP_ATOMIC);
+       if (!skb) {
+               printk(KERN_ERR "%s: no skb id %x\n", __func__,
+                   mISDN_HEAD_ID(dch->tx_skb));
+               return;
+       }
+       skb_queue_tail(&dch->rqueue, skb);
+       schedule_event(dch, FLG_RECVQUEUE);
+}
+
+int
+get_next_dframe(struct dchannel *dch)
+{
+       dch->tx_idx = 0;
+       dch->tx_skb = skb_dequeue(&dch->squeue);
+       if (dch->tx_skb) {
+               confirm_Dsend(dch);
+               return 1;
+       }
+       dch->tx_skb = NULL;
+       test_and_clear_bit(FLG_TX_BUSY, &dch->Flags);
+       return 0;
+}
+EXPORT_SYMBOL(get_next_dframe);
+
+void
+confirm_Bsend(struct bchannel *bch)
+{
+       struct sk_buff  *skb;
+
+       if (bch->rcount >= 64)
+               return;
+       skb = _alloc_mISDN_skb(PH_DATA_CNF, mISDN_HEAD_ID(bch->tx_skb),
+           0, NULL, GFP_ATOMIC);
+       if (!skb) {
+               printk(KERN_ERR "%s: no skb id %x\n", __func__,
+                   mISDN_HEAD_ID(bch->tx_skb));
+               return;
+       }
+       bch->rcount++;
+       skb_queue_tail(&bch->rqueue, skb);
+       schedule_event(bch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(confirm_Bsend);
+
+int
+get_next_bframe(struct bchannel *bch)
+{
+       bch->tx_idx = 0;
+       if (test_bit(FLG_TX_NEXT, &bch->Flags)) {
+               bch->tx_skb = bch->next_skb;
+               if (bch->tx_skb) {
+                       bch->next_skb = NULL;
+                       test_and_clear_bit(FLG_TX_NEXT, &bch->Flags);
+                       if (!test_bit(FLG_TRANSPARENT, &bch->Flags))
+                               confirm_Bsend(bch); /* not for transparent */
+                       return 1;
+               } else {
+                       test_and_clear_bit(FLG_TX_NEXT, &bch->Flags);
+                       printk(KERN_WARNING "B TX_NEXT without skb\n");
+               }
+       }
+       bch->tx_skb = NULL;
+       test_and_clear_bit(FLG_TX_BUSY, &bch->Flags);
+       return 0;
+}
+EXPORT_SYMBOL(get_next_bframe);
+
+void
+queue_ch_frame(struct mISDNchannel *ch, u_int pr, int id, struct sk_buff *skb)
+{
+       struct mISDNhead *hh;
+
+       if (!skb) {
+               _queue_data(ch, pr, id, 0, NULL, GFP_ATOMIC);
+       } else {
+               if (ch->peer) {
+                       hh = mISDN_HEAD_P(skb);
+                       hh->prim = pr;
+                       hh->id = id;
+                       if (!ch->recv(ch->peer, skb))
+                               return;
+               }
+               dev_kfree_skb(skb);
+       }
+}
+EXPORT_SYMBOL(queue_ch_frame);
+
+int
+dchannel_senddata(struct dchannel *ch, struct sk_buff *skb)
+{
+       /* check oversize */
+       if (skb->len <= 0) {
+               printk(KERN_WARNING "%s: skb too small\n", __func__);
+               return -EINVAL;
+       }
+       if (skb->len > ch->maxlen) {
+               printk(KERN_WARNING "%s: skb too large(%d/%d)\n",
+                       __func__, skb->len, ch->maxlen);
+               return -EINVAL;
+       }
+       /* HW lock must be obtained */
+       if (test_and_set_bit(FLG_TX_BUSY, &ch->Flags)) {
+               skb_queue_tail(&ch->squeue, skb);
+               return 0;
+       } else {
+               /* write to fifo */
+               ch->tx_skb = skb;
+               ch->tx_idx = 0;
+               return 1;
+       }
+}
+EXPORT_SYMBOL(dchannel_senddata);
+
+int
+bchannel_senddata(struct bchannel *ch, struct sk_buff *skb)
+{
+
+       /* check oversize */
+       if (skb->len <= 0) {
+               printk(KERN_WARNING "%s: skb too small\n", __func__);
+               return -EINVAL;
+       }
+       if (skb->len > ch->maxlen) {
+               printk(KERN_WARNING "%s: skb too large(%d/%d)\n",
+                       __func__, skb->len, ch->maxlen);
+               return -EINVAL;
+       }
+       /* HW lock must be obtained */
+       /* check for pending next_skb */
+       if (ch->next_skb) {
+               printk(KERN_WARNING
+                   "%s: next_skb exist ERROR (skb->len=%d next_skb->len=%d)\n",
+                   __func__, skb->len, ch->next_skb->len);
+               return -EBUSY;
+       }
+       if (test_and_set_bit(FLG_TX_BUSY, &ch->Flags)) {
+               test_and_set_bit(FLG_TX_NEXT, &ch->Flags);
+               ch->next_skb = skb;
+               return 0;
+       } else {
+               /* write to fifo */
+               ch->tx_skb = skb;
+               ch->tx_idx = 0;
+               return 1;
+       }
+}
+EXPORT_SYMBOL(bchannel_senddata);