[PATCH] isdn4linux: Siemens Gigaset drivers: make some variables non-atomic

With Hansjoerg Lipp <hjlipp@web.de>

Replace some atomic_t variables in the Gigaset drivers by non-atomic ones,
using spinlocks instead to assure atomicity, as proposed in discussions on the
linux-kernel mailing list.

Signed-off-by: Hansjoerg Lipp <hjlipp@web.de>
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 9 insertions, 10 deletions

diff --git a/drivers/isdn/gigaset/i4l.c b/drivers/isdn/gigaset/i4l.c
index 7059b84b96a..0815dbfb829 100644
--- a/drivers/isdn/gigaset/i4l.c
+++ b/drivers/isdn/gigaset/i4l.c
@@ -56,11 +56,6 @@ static int writebuf_from_LL(int driverID, int channel, int ack,
                 "Receiving data from LL (id: %d, ch: %d, ack: %d, sz: %d)",
                 driverID, channel, ack, len);
 
-        if (!atomic_read(&cs->connected)) {
-                err("%s: disconnected", __func__);
-                return -ENODEV;
-        }
-
         if (!len) {
                 if (ack)
                         notice("%s: not ACKing empty packet", __func__);
@@ -78,7 +73,7 @@ static int writebuf_from_LL(int driverID, int channel, int ack,
                 len, skblen, (unsigned) skb->head[0], (unsigned) skb->head[1]);
 
         /* pass to device-specific module */
-        return cs->ops->send_skb(bcs, skb);
+        return cs->ops->send_skb(bcs, skb); //FIXME cs->ops->send_skb() must handle !cs->connected correctly
 }
 
 void gigaset_skb_sent(struct bc_state *bcs, struct sk_buff *skb)
@@ -119,11 +114,12 @@ static int command_from_LL(isdn_ctrl *cntrl)
         struct bc_state *bcs;
         int retval = 0;
         struct setup_parm *sp;
+        unsigned param;
+        unsigned long flags;
 
         gigaset_debugdrivers();
 
-        //FIXME "remove test for &connected"
-        if ((!cs || !atomic_read(&cs->connected))) {
+        if (!cs) {
                 warn("LL tried to access unknown device with nr. %d",
                      cntrl->driver);
                 return -ENODEV;
@@ -166,8 +162,11 @@ static int command_from_LL(isdn_ctrl *cntrl)
                 }
                 *sp = cntrl->parm.setup;
 
-                if (!gigaset_add_event(cs, &bcs->at_state, EV_DIAL, sp,
-                                       atomic_read(&bcs->at_state.seq_index),
+                spin_lock_irqsave(&cs->lock, flags);
+                param = bcs->at_state.seq_index;
+                spin_unlock_irqrestore(&cs->lock, flags);
+
+                if (!gigaset_add_event(cs, &bcs->at_state, EV_DIAL, sp, param,
                                        NULL)) {
                         //FIXME what should we do?
                         kfree(sp);