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path: root/drivers/isdn/i4l/isdn_common.c
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Diffstat (limited to 'drivers/isdn/i4l/isdn_common.c')
-rw-r--r--drivers/isdn/i4l/isdn_common.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/isdn/i4l/isdn_common.c b/drivers/isdn/i4l/isdn_common.c
index 4643df097bf..22759c01746 100644
--- a/drivers/isdn/i4l/isdn_common.c
+++ b/drivers/isdn/i4l/isdn_common.c
@@ -857,6 +857,118 @@ isdn_readbchan(int di, int channel, u_char * buf, u_char * fp, int len, wait_que
return count;
}
+/*
+ * isdn_readbchan_tty() tries to get data from the read-queue.
+ * It MUST be called with interrupts off.
+ *
+ * Be aware that this is not an atomic operation when sleep != 0, even though
+ * interrupts are turned off! Well, like that we are currently only called
+ * on behalf of a read system call on raw device files (which are documented
+ * to be dangerous and for for debugging purpose only). The inode semaphore
+ * takes care that this is not called for the same minor device number while
+ * we are sleeping, but access is not serialized against simultaneous read()
+ * from the corresponding ttyI device. Can other ugly events, like changes
+ * of the mapping (di,ch)<->minor, happen during the sleep? --he
+ */
+int
+isdn_readbchan_tty(int di, int channel, struct tty_struct *tty, int cisco_hack)
+{
+ int count;
+ int count_pull;
+ int count_put;
+ int dflag;
+ struct sk_buff *skb;
+ char last = 0;
+ int len;
+
+ if (!dev->drv[di])
+ return 0;
+ if (skb_queue_empty(&dev->drv[di]->rpqueue[channel]))
+ return 0;
+
+ len = tty_buffer_request_room(tty, dev->drv[di]->rcvcount[channel]);
+ if(len == 0)
+ return len;
+
+ count = 0;
+ while (len) {
+ if (!(skb = skb_peek(&dev->drv[di]->rpqueue[channel])))
+ break;
+#ifdef CONFIG_ISDN_AUDIO
+ if (ISDN_AUDIO_SKB_LOCK(skb))
+ break;
+ ISDN_AUDIO_SKB_LOCK(skb) = 1;
+ if ((ISDN_AUDIO_SKB_DLECOUNT(skb)) || (dev->drv[di]->DLEflag & (1 << channel))) {
+ char *p = skb->data;
+ unsigned long DLEmask = (1 << channel);
+
+ dflag = 0;
+ count_pull = count_put = 0;
+ while ((count_pull < skb->len) && (len > 0)) {
+ len--;
+ if (dev->drv[di]->DLEflag & DLEmask) {
+ last = DLE;
+ dev->drv[di]->DLEflag &= ~DLEmask;
+ } else {
+ last = *p;
+ if (last == DLE) {
+ dev->drv[di]->DLEflag |= DLEmask;
+ (ISDN_AUDIO_SKB_DLECOUNT(skb))--;
+ }
+ p++;
+ count_pull++;
+ }
+ count_put++;
+ }
+ if (count_pull >= skb->len)
+ dflag = 1;
+ } else {
+#endif
+ /* No DLE's in buff, so simply copy it */
+ dflag = 1;
+ if ((count_pull = skb->len) > len) {
+ count_pull = len;
+ dflag = 0;
+ }
+ count_put = count_pull;
+ if(count_put > 1)
+ tty_insert_flip_string(tty, skb->data, count_put - 1);
+ last = skb->data[count_put] - 1;
+ len -= count_put;
+#ifdef CONFIG_ISDN_AUDIO
+ }
+#endif
+ count += count_put;
+ if (dflag) {
+ /* We got all the data in this buff.
+ * Now we can dequeue it.
+ */
+ if(cisco_hack)
+ tty_insert_flip_char(tty, last, 0xFF);
+ else
+ tty_insert_flip_char(tty, last, TTY_NORMAL);
+#ifdef CONFIG_ISDN_AUDIO
+ ISDN_AUDIO_SKB_LOCK(skb) = 0;
+#endif
+ skb = skb_dequeue(&dev->drv[di]->rpqueue[channel]);
+ dev_kfree_skb(skb);
+ } else {
+ tty_insert_flip_char(tty, last, TTY_NORMAL);
+ /* Not yet emptied this buff, so it
+ * must stay in the queue, for further calls
+ * but we pull off the data we got until now.
+ */
+ skb_pull(skb, count_pull);
+#ifdef CONFIG_ISDN_AUDIO
+ ISDN_AUDIO_SKB_LOCK(skb) = 0;
+#endif
+ }
+ dev->drv[di]->rcvcount[channel] -= count_put;
+ }
+ return count;
+}
+
+
static __inline int
isdn_minor2drv(int minor)
{