1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/isdn/gigaset/i4l.c b/drivers/isdn/gigaset/i4l.c
index 9b22f9cf2f33..654489d836cd 100644
--- a/drivers/isdn/gigaset/i4l.c
+++ b/drivers/isdn/gigaset/i4l.c
@@ -51,6 +51,12 @@ static int writebuf_from_LL(int driverID, int channel, int ack,
                 return -ENODEV;
         }
         bcs = &cs->bcs[channel];
+
+        /* can only handle linear sk_buffs */
+        if (skb_linearize(skb) < 0) {
+                dev_err(cs->dev, "%s: skb_linearize failed\n", __func__);
+                return -ENOMEM;
+        }
         len = skb->len;
 
         gig_dbg(DEBUG_LLDATA,
@@ -79,6 +85,14 @@ static int writebuf_from_LL(int driverID, int channel, int ack,
         return cs->ops->send_skb(bcs, skb);
 }
 
+/**
+ * gigaset_skb_sent() - acknowledge sending an skb
+ * @bcs:        B channel descriptor structure.
+ * @skb:        sent data.
+ *
+ * Called by hardware module {bas,ser,usb}_gigaset when the data in a
+ * skb has been successfully sent, for signalling completion to the LL.
+ */
 void gigaset_skb_sent(struct bc_state *bcs, struct sk_buff *skb)
 {
         unsigned len;
@@ -455,6 +469,15 @@ int gigaset_isdn_setup_accept(struct at_state_t *at_state)
         return 0;
 }
 
+/**
+ * gigaset_isdn_icall() - signal incoming call
+ * @at_state:   connection state structure.
+ *
+ * Called by main module to notify the LL that an incoming call has been
+ * received. @at_state contains the parameters of the call.
+ *
+ * Return value: call disposition (ICALL_*)
+ */
 int gigaset_isdn_icall(struct at_state_t *at_state)
 {
         struct cardstate *cs = at_state->cs;