1 files changed, 238 insertions, 216 deletions

diff --git a/drivers/isdn/gigaset/common.c b/drivers/isdn/gigaset/common.c
index 0048ce98bfa..7c7814497e3 100644
--- a/drivers/isdn/gigaset/common.c
+++ b/drivers/isdn/gigaset/common.c
@@ -14,7 +14,6 @@
  */
 
 #include "gigaset.h"
-#include <linux/ctype.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 
@@ -22,16 +21,33 @@
 #define DRIVER_AUTHOR "Hansjoerg Lipp <hjlipp@web.de>, Tilman Schmidt <tilman@imap.cc>, Stefan Eilers"
 #define DRIVER_DESC "Driver for Gigaset 307x"
 
+#ifdef CONFIG_GIGASET_DEBUG
+#define DRIVER_DESC_DEBUG " (debug build)"
+#else
+#define DRIVER_DESC_DEBUG ""
+#endif
+
 /* Module parameters */
-int gigaset_debuglevel = DEBUG_DEFAULT;
+int gigaset_debuglevel;
 EXPORT_SYMBOL_GPL(gigaset_debuglevel);
-module_param_named(debug, gigaset_debuglevel, int, S_IRUGO|S_IWUSR);
+module_param_named(debug, gigaset_debuglevel, int, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(debug, "debug level");
 
 /* driver state flags */
 #define VALID_MINOR	0x01
 #define VALID_ID	0x02
 
+/**
+ * gigaset_dbg_buffer() - dump data in ASCII and hex for debugging
+ * @level:	debugging level.
+ * @msg:	message prefix.
+ * @len:	number of bytes to dump.
+ * @buf:	data to dump.
+ *
+ * If the current debugging level includes one of the bits set in @level,
+ * @len bytes starting at @buf are logged to dmesg at KERN_DEBUG prio,
+ * prefixed by the text @msg.
+ */
 void gigaset_dbg_buffer(enum debuglevel level, const unsigned char *msg,
 			size_t len, const unsigned char *buf)
 {
@@ -91,7 +107,7 @@ int gigaset_enterconfigmode(struct cardstate *cs)
 {
 	int i, r;
 
-	cs->control_state = TIOCM_RTS; //FIXME
+	cs->control_state = TIOCM_RTS;
 
 	r = setflags(cs, TIOCM_DTR, 200);
 	if (r < 0)
@@ -107,7 +123,7 @@ int gigaset_enterconfigmode(struct cardstate *cs)
 		if (r < 0)
 			goto error;
 	}
-	r = setflags(cs, TIOCM_RTS|TIOCM_DTR, 800);
+	r = setflags(cs, TIOCM_RTS | TIOCM_DTR, 800);
 	if (r < 0)
 		goto error;
 
@@ -115,10 +131,10 @@ int gigaset_enterconfigmode(struct cardstate *cs)
 
 error:
 	dev_err(cs->dev, "error %d on setuartbits\n", -r);
-	cs->control_state = TIOCM_RTS|TIOCM_DTR; // FIXME is this a good value?
-	cs->ops->set_modem_ctrl(cs, 0, TIOCM_RTS|TIOCM_DTR);
+	cs->control_state = TIOCM_RTS | TIOCM_DTR;
+	cs->ops->set_modem_ctrl(cs, 0, TIOCM_RTS | TIOCM_DTR);
 
-	return -1; //r
+	return -1;
 }
 
 static int test_timeout(struct at_state_t *at_state)
@@ -132,11 +148,8 @@ static int test_timeout(struct at_state_t *at_state)
 		return 0;
 	}
 
-	if (!gigaset_add_event(at_state->cs, at_state, EV_TIMEOUT, NULL,
-			       at_state->timer_index, NULL)) {
-		//FIXME what should we do?
-	}
-
+	gigaset_add_event(at_state->cs, at_state, EV_TIMEOUT, NULL,
+			  at_state->timer_index, NULL);
 	return 1;
 }
 
@@ -164,7 +177,7 @@ static void timer_tick(unsigned long data)
 	if (cs->running) {
 		mod_timer(&cs->timer, jiffies + msecs_to_jiffies(GIG_TICK));
 		if (timeout) {
-			gig_dbg(DEBUG_CMD, "scheduling timeout");
+			gig_dbg(DEBUG_EVENT, "scheduling timeout");
 			tasklet_schedule(&cs->event_tasklet);
 		}
 	}
@@ -178,16 +191,42 @@ int gigaset_get_channel(struct bc_state *bcs)
 
 	spin_lock_irqsave(&bcs->cs->lock, flags);
 	if (bcs->use_count || !try_module_get(bcs->cs->driver->owner)) {
-		gig_dbg(DEBUG_ANY, "could not allocate channel %d",
+		gig_dbg(DEBUG_CHANNEL, "could not allocate channel %d",
 			bcs->channel);
 		spin_unlock_irqrestore(&bcs->cs->lock, flags);
-		return 0;
+		return -EBUSY;
 	}
 	++bcs->use_count;
 	bcs->busy = 1;
-	gig_dbg(DEBUG_ANY, "allocated channel %d", bcs->channel);
+	gig_dbg(DEBUG_CHANNEL, "allocated channel %d", bcs->channel);
 	spin_unlock_irqrestore(&bcs->cs->lock, flags);
-	return 1;
+	return 0;
+}
+
+struct bc_state *gigaset_get_free_channel(struct cardstate *cs)
+{
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(&cs->lock, flags);
+	if (!try_module_get(cs->driver->owner)) {
+		gig_dbg(DEBUG_CHANNEL,
+			"could not get module for allocating channel");
+		spin_unlock_irqrestore(&cs->lock, flags);
+		return NULL;
+	}
+	for (i = 0; i < cs->channels; ++i)
+		if (!cs->bcs[i].use_count) {
+			++cs->bcs[i].use_count;
+			cs->bcs[i].busy = 1;
+			spin_unlock_irqrestore(&cs->lock, flags);
+			gig_dbg(DEBUG_CHANNEL, "allocated channel %d", i);
+			return cs->bcs + i;
+		}
+	module_put(cs->driver->owner);
+	spin_unlock_irqrestore(&cs->lock, flags);
+	gig_dbg(DEBUG_CHANNEL, "no free channel");
+	return NULL;
 }
 
 void gigaset_free_channel(struct bc_state *bcs)
@@ -196,14 +235,15 @@ void gigaset_free_channel(struct bc_state *bcs)
 
 	spin_lock_irqsave(&bcs->cs->lock, flags);
 	if (!bcs->busy) {
-		gig_dbg(DEBUG_ANY, "could not free channel %d", bcs->channel);
+		gig_dbg(DEBUG_CHANNEL, "could not free channel %d",
+			bcs->channel);
 		spin_unlock_irqrestore(&bcs->cs->lock, flags);
 		return;
 	}
 	--bcs->use_count;
 	bcs->busy = 0;
 	module_put(bcs->cs->driver->owner);
-	gig_dbg(DEBUG_ANY, "freed channel %d", bcs->channel);
+	gig_dbg(DEBUG_CHANNEL, "freed channel %d", bcs->channel);
 	spin_unlock_irqrestore(&bcs->cs->lock, flags);
 }
 
@@ -216,16 +256,17 @@ int gigaset_get_channels(struct cardstate *cs)
 	for (i = 0; i < cs->channels; ++i)
 		if (cs->bcs[i].use_count) {
 			spin_unlock_irqrestore(&cs->lock, flags);
-			gig_dbg(DEBUG_ANY, "could not allocate all channels");
-			return 0;
+			gig_dbg(DEBUG_CHANNEL,
+				"could not allocate all channels");
+			return -EBUSY;
 		}
 	for (i = 0; i < cs->channels; ++i)
 		++cs->bcs[i].use_count;
 	spin_unlock_irqrestore(&cs->lock, flags);
 
-	gig_dbg(DEBUG_ANY, "allocated all channels");
+	gig_dbg(DEBUG_CHANNEL, "allocated all channels");
 
-	return 1;
+	return 0;
 }
 
 void gigaset_free_channels(struct cardstate *cs)
@@ -233,7 +274,7 @@ void gigaset_free_channels(struct cardstate *cs)
 	unsigned long flags;
 	int i;
 
-	gig_dbg(DEBUG_ANY, "unblocking all channels");
+	gig_dbg(DEBUG_CHANNEL, "unblocking all channels");
 	spin_lock_irqsave(&cs->lock, flags);
 	for (i = 0; i < cs->channels; ++i)
 		--cs->bcs[i].use_count;
@@ -245,7 +286,7 @@ void gigaset_block_channels(struct cardstate *cs)
 	unsigned long flags;
 	int i;
 
-	gig_dbg(DEBUG_ANY, "blocking all channels");
+	gig_dbg(DEBUG_CHANNEL, "blocking all channels");
 	spin_lock_irqsave(&cs->lock, flags);
 	for (i = 0; i < cs->channels; ++i)
 		++cs->bcs[i].use_count;
@@ -274,6 +315,20 @@ static void clear_events(struct cardstate *cs)
 	spin_unlock_irqrestore(&cs->ev_lock, flags);
 }
 
+/**
+ * gigaset_add_event() - add event to device event queue
+ * @cs:		device descriptor structure.
+ * @at_state:	connection state structure.
+ * @type:	event type.
+ * @ptr:	pointer parameter for event.
+ * @parameter:	integer parameter for event.
+ * @arg:	pointer parameter for event.
+ *
+ * Allocate an event queue entry from the device's event queue, and set it up
+ * with the parameters given.
+ *
+ * Return value: added event
+ */
 struct event_t *gigaset_add_event(struct cardstate *cs,
 				  struct at_state_t *at_state, int type,
 				  void *ptr, int parameter, void *arg)
@@ -282,6 +337,8 @@ struct event_t *gigaset_add_event(struct cardstate *cs,
 	unsigned next, tail;
 	struct event_t *event = NULL;
 
+	gig_dbg(DEBUG_EVENT, "queueing event %d", type);
+
 	spin_lock_irqsave(&cs->ev_lock, flags);
 
 	tail = cs->ev_tail;
@@ -305,7 +362,7 @@ struct event_t *gigaset_add_event(struct cardstate *cs,
 }
 EXPORT_SYMBOL_GPL(gigaset_add_event);
 
-static void free_strings(struct at_state_t *at_state)
+static void clear_at_state(struct at_state_t *at_state)
 {
 	int i;
 
@@ -315,18 +372,13 @@ static void free_strings(struct at_state_t *at_state)
 	}
 }
 
-static void clear_at_state(struct at_state_t *at_state)
-{
-	free_strings(at_state);
-}
-
-static void dealloc_at_states(struct cardstate *cs)
+static void dealloc_temp_at_states(struct cardstate *cs)
 {
 	struct at_state_t *cur, *next;
 
 	list_for_each_entry_safe(cur, next, &cs->temp_at_states, list) {
 		list_del(&cur->list);
-		free_strings(cur);
+		clear_at_state(cur);
 		kfree(cur);
 	}
 }
@@ -336,16 +388,14 @@ static void gigaset_freebcs(struct bc_state *bcs)
 	int i;
 
 	gig_dbg(DEBUG_INIT, "freeing bcs[%d]->hw", bcs->channel);
-	if (!bcs->cs->ops->freebcshw(bcs)) {
-		gig_dbg(DEBUG_INIT, "failed");
-	}
+	bcs->cs->ops->freebcshw(bcs);
 
 	gig_dbg(DEBUG_INIT, "clearing bcs[%d]->at_state", bcs->channel);
 	clear_at_state(&bcs->at_state);
 	gig_dbg(DEBUG_INIT, "freeing bcs[%d]->skb", bcs->channel);
+	dev_kfree_skb(bcs->rx_skb);
+	bcs->rx_skb = NULL;
 
-	if (bcs->skb)
-		dev_kfree_skb(bcs->skb);
 	for (i = 0; i < AT_NUM; ++i) {
 		kfree(bcs->commands[i]);
 		bcs->commands[i] = NULL;
@@ -398,6 +448,15 @@ static void make_invalid(struct cardstate *cs, unsigned mask)
 	spin_unlock_irqrestore(&drv->lock, flags);
 }
 
+/**
+ * gigaset_freecs() - free all associated ressources of a device
+ * @cs:		device descriptor structure.
+ *
+ * Stops all tasklets and timers, unregisters the device from all
+ * subsystems it was registered to, deallocates the device structure
+ * @cs and all structures referenced from it.
+ * Operations on the device should be stopped before calling this.
+ */
 void gigaset_freecs(struct cardstate *cs)
 {
 	int i;
@@ -408,11 +467,6 @@ void gigaset_freecs(struct cardstate *cs)
 
 	mutex_lock(&cs->mutex);
 
-	if (!cs->bcs)
-		goto f_cs;
-	if (!cs->inbuf)
-		goto f_bcs;
-
 	spin_lock_irqsave(&cs->lock, flags);
 	cs->running = 0;
 	spin_unlock_irqrestore(&cs->lock, flags); /* event handler and timer are
@@ -423,6 +477,12 @@ void gigaset_freecs(struct cardstate *cs)
 
 	switch (cs->cs_init) {
 	default:
+		/* clear B channel structures */
+		for (i = 0; i < cs->channels; ++i) {
+			gig_dbg(DEBUG_INIT, "clearing bcs[%d]", i);
+			gigaset_freebcs(cs->bcs + i);
+		}
+
 		/* clear device sysfs */
 		gigaset_free_dev_sysfs(cs);
 
@@ -431,35 +491,27 @@ void gigaset_freecs(struct cardstate *cs)
 		gig_dbg(DEBUG_INIT, "clearing hw");
 		cs->ops->freecshw(cs);
 
-		//FIXME cmdbuf
-
 		/* fall through */
 	case 2: /* error in initcshw */
 		/* Deregister from LL */
 		make_invalid(cs, VALID_ID);
-		gig_dbg(DEBUG_INIT, "clearing iif");
-		gigaset_i4l_cmd(cs, ISDN_STAT_UNLOAD);
+		gigaset_isdn_unregdev(cs);
 
 		/* fall through */
-	case 1: /* error when regestering to LL */
+	case 1: /* error when registering to LL */
 		gig_dbg(DEBUG_INIT, "clearing at_state");
 		clear_at_state(&cs->at_state);
-		dealloc_at_states(cs);
+		dealloc_temp_at_states(cs);
+		clear_events(cs);
+		tty_port_destroy(&cs->port);
 
 		/* fall through */
-	case 0: /* error in one call to initbcs */
-		for (i = 0; i < cs->channels; ++i) {
-			gig_dbg(DEBUG_INIT, "clearing bcs[%d]", i);
-			gigaset_freebcs(cs->bcs + i);
-		}
-
-		clear_events(cs);
+	case 0:	/* error in basic setup */
 		gig_dbg(DEBUG_INIT, "freeing inbuf");
 		kfree(cs->inbuf);
+		kfree(cs->bcs);
 	}
-f_bcs:	gig_dbg(DEBUG_INIT, "freeing bcs[]");
-	kfree(cs->bcs);
-f_cs:	gig_dbg(DEBUG_INIT, "freeing cs");
+
 	mutex_unlock(&cs->mutex);
 	free_cs(cs);
 }
@@ -494,19 +546,23 @@ void gigaset_at_init(struct at_state_t *at_state, struct bc_state *bcs,
 }
 
 
-static void gigaset_inbuf_init(struct inbuf_t *inbuf, struct bc_state *bcs,
-			       struct cardstate *cs, int inputstate)
+static void gigaset_inbuf_init(struct inbuf_t *inbuf, struct cardstate *cs)
 /* inbuf->read must be allocated before! */
 {
 	inbuf->head = 0;
 	inbuf->tail = 0;
 	inbuf->cs = cs;
-	inbuf->bcs = bcs; /*base driver: NULL*/
-	inbuf->rcvbuf = NULL;
-	inbuf->inputstate = inputstate;
+	inbuf->inputstate = INS_command;
 }
 
-/* append received bytes to inbuf */
+/**
+ * gigaset_fill_inbuf() - append received data to input buffer
+ * @inbuf:	buffer structure.
+ * @src:	received data.
+ * @numbytes:	number of bytes received.
+ *
+ * Return value: !=0 if some data was appended
+ */
 int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 		       unsigned numbytes)
 {
@@ -526,7 +582,7 @@ int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 		if (head > tail)
 			n = head - 1 - tail;
 		else if (head == 0)
-			n = (RBUFSIZE-1) - tail;
+			n = (RBUFSIZE - 1) - tail;
 		else
 			n = RBUFSIZE - tail;
 		if (!n) {
@@ -549,12 +605,12 @@ int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 EXPORT_SYMBOL_GPL(gigaset_fill_inbuf);
 
 /* Initialize the b-channel structure */
-static struct bc_state *gigaset_initbcs(struct bc_state *bcs,
-					struct cardstate *cs, int channel)
+static int gigaset_initbcs(struct bc_state *bcs, struct cardstate *cs,
+			   int channel)
 {
 	int i;
 
-	bcs->tx_skb = NULL; //FIXME -> hw part
+	bcs->tx_skb = NULL;
 
 	skb_queue_head_init(&bcs->squeue);
 
@@ -565,25 +621,14 @@ static struct bc_state *gigaset_initbcs(struct bc_state *bcs,
 	gig_dbg(DEBUG_INIT, "setting up bcs[%d]->at_state", channel);
 	gigaset_at_init(&bcs->at_state, bcs, cs, -1);
 
-	bcs->rcvbytes = 0;
-
 #ifdef CONFIG_GIGASET_DEBUG
 	bcs->emptycount = 0;
 #endif
 
-	gig_dbg(DEBUG_INIT, "allocating bcs[%d]->skb", channel);
-	bcs->fcs = PPP_INITFCS;
+	bcs->rx_bufsize = 0;
+	bcs->rx_skb = NULL;
+	bcs->rx_fcs = PPP_INITFCS;
 	bcs->inputstate = 0;
-	if (cs->ignoreframes) {
-		bcs->inputstate |= INS_skip_frame;
-		bcs->skb = NULL;
-	} else if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL)
-		skb_reserve(bcs->skb, HW_HDR_LEN);
-	else {
-		pr_err("out of memory\n");
-		bcs->inputstate |= INS_skip_frame;
-	}
-
 	bcs->channel = channel;
 	bcs->cs = cs;
 
@@ -595,62 +640,47 @@ static struct bc_state *gigaset_initbcs(struct bc_state *bcs,
 	for (i = 0; i < AT_NUM; ++i)
 		bcs->commands[i] = NULL;
 
-	gig_dbg(DEBUG_INIT, "  setting up bcs[%d]->hw", channel);
-	if (cs->ops->initbcshw(bcs))
-		return bcs;
-
-	gig_dbg(DEBUG_INIT, "  failed");
-
-	gig_dbg(DEBUG_INIT, "  freeing bcs[%d]->skb", channel);
-	if (bcs->skb)
-		dev_kfree_skb(bcs->skb);
+	spin_lock_init(&bcs->aplock);
+	bcs->ap = NULL;
+	bcs->apconnstate = 0;
 
-	return NULL;
+	gig_dbg(DEBUG_INIT, "  setting up bcs[%d]->hw", channel);
+	return cs->ops->initbcshw(bcs);
 }
 
-/* gigaset_initcs
+/**
+ * gigaset_initcs() - initialize device structure
+ * @drv:	hardware driver the device belongs to
+ * @channels:	number of B channels supported by device
+ * @onechannel:	!=0 if B channel data and AT commands share one
+ *		    communication channel (M10x),
+ *		==0 if B channels have separate communication channels (base)
+ * @ignoreframes:	number of frames to ignore after setting up B channel
+ * @cidmode:	!=0: start in CallID mode
+ * @modulename:	name of driver module for LL registration
+ *
  * Allocate and initialize cardstate structure for Gigaset driver
  * Calls hardware dependent gigaset_initcshw() function
  * Calls B channel initialization function gigaset_initbcs() for each B channel
- * parameters:
- *	drv		hardware driver the device belongs to
- *	channels	number of B channels supported by device
- *	onechannel	!=0: B channel data and AT commands share one
- *			     communication channel
- *			==0: B channels have separate communication channels
- *	ignoreframes	number of frames to ignore after setting up B channel
- *	cidmode		!=0: start in CallID mode
- *	modulename	name of driver module (used for I4L registration)
- * return value:
+ *
+ * Return value:
  *	pointer to cardstate structure
  */
 struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 				 int onechannel, int ignoreframes,
 				 int cidmode, const char *modulename)
 {
-	struct cardstate *cs = NULL;
+	struct cardstate *cs;
 	unsigned long flags;
 	int i;
 
 	gig_dbg(DEBUG_INIT, "allocating cs");
-	if (!(cs = alloc_cs(drv))) {
+	cs = alloc_cs(drv);
+	if (!cs) {
 		pr_err("maximum number of devices exceeded\n");
 		return NULL;
 	}
 
-	gig_dbg(DEBUG_INIT, "allocating bcs[0..%d]", channels - 1);
-	cs->bcs = kmalloc(channels * sizeof(struct bc_state), GFP_KERNEL);
-	if (!cs->bcs) {
-		pr_err("out of memory\n");
-		goto error;
-	}
-	gig_dbg(DEBUG_INIT, "allocating inbuf");
-	cs->inbuf = kmalloc(sizeof(struct inbuf_t), GFP_KERNEL);
-	if (!cs->inbuf) {
-		pr_err("out of memory\n");
-		goto error;
-	}
-
 	cs->cs_init = 0;
 	cs->channels = channels;
 	cs->onechannel = onechannel;
@@ -662,24 +692,17 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	cs->ev_tail = 0;
 	cs->ev_head = 0;
 
-	tasklet_init(&cs->event_tasklet, &gigaset_handle_event,
+	tasklet_init(&cs->event_tasklet, gigaset_handle_event,
 		     (unsigned long) cs);
+	tty_port_init(&cs->port);
 	cs->commands_pending = 0;
 	cs->cur_at_seq = 0;
 	cs->gotfwver = -1;
-	cs->open_count = 0;
 	cs->dev = NULL;
-	cs->tty = NULL;
 	cs->tty_dev = NULL;
 	cs->cidmode = cidmode != 0;
-
-	//if(onechannel) { //FIXME
-		cs->tabnocid = gigaset_tab_nocid_m10x;
-		cs->tabcid = gigaset_tab_cid_m10x;
-	//} else {
-	//	cs->tabnocid = gigaset_tab_nocid;
-	//	cs->tabcid = gigaset_tab_cid;
-	//}
+	cs->tabnocid = gigaset_tab_nocid;
+	cs->tabcid = gigaset_tab_cid;
 
 	init_waitqueue_head(&cs->waitqueue);
 	cs->waiting = 0;
@@ -687,14 +710,12 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	cs->mode = M_UNKNOWN;
 	cs->mstate = MS_UNINITIALIZED;
 
-	for (i = 0; i < channels; ++i) {
-		gig_dbg(DEBUG_INIT, "setting up bcs[%d].read", i);
-		if (!gigaset_initbcs(cs->bcs + i, cs, i)) {
-			pr_err("could not allocate channel %d data\n", i);
-			goto error;
-		}
+	cs->bcs = kmalloc(channels * sizeof(struct bc_state), GFP_KERNEL);
+	cs->inbuf = kmalloc(sizeof(struct inbuf_t), GFP_KERNEL);
+	if (!cs->bcs || !cs->inbuf) {
+		pr_err("out of memory\n");
+		goto error;
 	}
-
 	++cs->cs_init;
 
 	gig_dbg(DEBUG_INIT, "setting up at_state");
@@ -704,10 +725,7 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	cs->cbytes = 0;
 
 	gig_dbg(DEBUG_INIT, "setting up inbuf");
-	if (onechannel) {			//FIXME distinction necessary?
-		gigaset_inbuf_init(cs->inbuf, cs->bcs, cs, INS_command);
-	} else
-		gigaset_inbuf_init(cs->inbuf, NULL,    cs, INS_command);
+	gigaset_inbuf_init(cs->inbuf, cs);
 
 	cs->connected = 0;
 	cs->isdn_up = 0;
@@ -719,7 +737,7 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	cs->cmdbytes = 0;
 
 	gig_dbg(DEBUG_INIT, "setting up iif");
-	if (!gigaset_register_to_LL(cs, modulename)) {
+	if (gigaset_isdn_regdev(cs, modulename) < 0) {
 		pr_err("error registering ISDN device\n");
 		goto error;
 	}
@@ -727,7 +745,7 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	make_valid(cs, VALID_ID);
 	++cs->cs_init;
 	gig_dbg(DEBUG_INIT, "setting up hw");
-	if (!cs->ops->initcshw(cs))
+	if (cs->ops->initcshw(cs) < 0)
 		goto error;
 
 	++cs->cs_init;
@@ -738,13 +756,20 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	/* set up device sysfs */
 	gigaset_init_dev_sysfs(cs);
 
+	/* set up channel data structures */
+	for (i = 0; i < channels; ++i) {
+		gig_dbg(DEBUG_INIT, "setting up bcs[%d]", i);
+		if (gigaset_initbcs(cs->bcs + i, cs, i) < 0) {
+			pr_err("could not allocate channel %d data\n", i);
+			goto error;
+		}
+	}
+
 	spin_lock_irqsave(&cs->lock, flags);
 	cs->running = 1;
 	spin_unlock_irqrestore(&cs->lock, flags);
 	setup_timer(&cs->timer, timer_tick, (unsigned long) cs);
 	cs->timer.expires = jiffies + msecs_to_jiffies(GIG_TICK);
-	/* FIXME: can jiffies increase too much until the timer is added?
-	 * Same problem(?) with mod_timer() in timer_tick(). */
 	add_timer(&cs->timer);
 
 	gig_dbg(DEBUG_INIT, "cs initialized");
@@ -781,13 +806,12 @@ void gigaset_bcs_reinit(struct bc_state *bcs)
 	bcs->emptycount = 0;
 #endif
 
-	bcs->fcs = PPP_INITFCS;
+	bcs->rx_fcs = PPP_INITFCS;
 	bcs->chstate = 0;
 
 	bcs->ignore = cs->ignoreframes;
-	if (bcs->ignore)
-		bcs->inputstate |= INS_skip_frame;
-
+	dev_kfree_skb(bcs->rx_skb);
+	bcs->rx_skb = NULL;
 
 	cs->ops->reinitbcshw(bcs);
 }
@@ -804,12 +828,9 @@ static void cleanup_cs(struct cardstate *cs)
 	cs->mstate = MS_UNINITIALIZED;
 
 	clear_at_state(&cs->at_state);
-	dealloc_at_states(cs);
-	free_strings(&cs->at_state);
+	dealloc_temp_at_states(cs);
 	gigaset_at_init(&cs->at_state, NULL, cs, 0);
 
-	kfree(cs->inbuf->rcvbuf);
-	cs->inbuf->rcvbuf = NULL;
 	cs->inbuf->inputstate = INS_command;
 	cs->inbuf->head = 0;
 	cs->inbuf->tail = 0;
@@ -833,7 +854,7 @@ static void cleanup_cs(struct cardstate *cs)
 
 	for (i = 0; i < cs->channels; ++i) {
 		gigaset_freebcs(cs->bcs + i);
-		if (!gigaset_initbcs(cs->bcs + i, cs, i))
+		if (gigaset_initbcs(cs->bcs + i, cs, i) < 0)
 			pr_err("could not allocate channel %d data\n", i);
 	}
 
@@ -845,51 +866,63 @@ static void cleanup_cs(struct cardstate *cs)
 }
 
 
+/**
+ * gigaset_start() - start device operations
+ * @cs:		device descriptor structure.
+ *
+ * Prepares the device for use by setting up communication parameters,
+ * scheduling an EV_START event to initiate device initialization, and
+ * waiting for completion of the initialization.
+ *
+ * Return value:
+ *	0 on success, error code < 0 on failure
+ */
 int gigaset_start(struct cardstate *cs)
 {
 	unsigned long flags;
 
 	if (mutex_lock_interruptible(&cs->mutex))
-		return 0;
+		return -EBUSY;
 
 	spin_lock_irqsave(&cs->lock, flags);
 	cs->connected = 1;
 	spin_unlock_irqrestore(&cs->lock, flags);
 
 	if (cs->mstate != MS_LOCKED) {
-		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
+		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR | TIOCM_RTS);
 		cs->ops->baud_rate(cs, B115200);
 		cs->ops->set_line_ctrl(cs, CS8);
-		cs->control_state = TIOCM_DTR|TIOCM_RTS;
-	} else {
-		//FIXME use some saved values?
+		cs->control_state = TIOCM_DTR | TIOCM_RTS;
 	}
 
 	cs->waiting = 1;
 
 	if (!gigaset_add_event(cs, &cs->at_state, EV_START, NULL, 0, NULL)) {
 		cs->waiting = 0;
-		//FIXME what should we do?
 		goto error;
 	}
-
-	gig_dbg(DEBUG_CMD, "scheduling START");
 	gigaset_schedule_event(cs);
 
 	wait_event(cs->waitqueue, !cs->waiting);
 
 	mutex_unlock(&cs->mutex);
-	return 1;
+	return 0;
 
 error:
 	mutex_unlock(&cs->mutex);
-	return 0;
+	return -ENOMEM;
 }
 EXPORT_SYMBOL_GPL(gigaset_start);
 
-/* gigaset_shutdown
- * check if a device is associated to the cardstate structure and stop it
- * return value: 0 if ok, -1 if no device was associated
+/**
+ * gigaset_shutdown() - shut down device operations
+ * @cs:		device descriptor structure.
+ *
+ * Deactivates the device by scheduling an EV_SHUTDOWN event and
+ * waiting for completion of the shutdown.
+ *
+ * Return value:
+ *	0 - success, -ENODEV - error (no device associated)
  */
 int gigaset_shutdown(struct cardstate *cs)
 {
@@ -897,17 +930,13 @@ int gigaset_shutdown(struct cardstate *cs)
 
 	if (!(cs->flags & VALID_MINOR)) {
 		mutex_unlock(&cs->mutex);
-		return -1;
+		return -ENODEV;
 	}
 
 	cs->waiting = 1;
 
-	if (!gigaset_add_event(cs, &cs->at_state, EV_SHUTDOWN, NULL, 0, NULL)) {
-		//FIXME what should we do?
+	if (!gigaset_add_event(cs, &cs->at_state, EV_SHUTDOWN, NULL, 0, NULL))
 		goto exit;
-	}
-
-	gig_dbg(DEBUG_CMD, "scheduling SHUTDOWN");
 	gigaset_schedule_event(cs);
 
 	wait_event(cs->waitqueue, !cs->waiting);
@@ -920,18 +949,21 @@ exit:
 }
 EXPORT_SYMBOL_GPL(gigaset_shutdown);
 
+/**
+ * gigaset_stop() - stop device operations
+ * @cs:		device descriptor structure.
+ *
+ * Stops operations on the device by scheduling an EV_STOP event and
+ * waiting for completion of the shutdown.
+ */
 void gigaset_stop(struct cardstate *cs)
 {
 	mutex_lock(&cs->mutex);
 
 	cs->waiting = 1;
 
-	if (!gigaset_add_event(cs, &cs->at_state, EV_STOP, NULL, 0, NULL)) {
-		//FIXME what should we do?
+	if (!gigaset_add_event(cs, &cs->at_state, EV_STOP, NULL, 0, NULL))
 		goto exit;
-	}
-
-	gig_dbg(DEBUG_CMD, "scheduling STOP");
 	gigaset_schedule_event(cs);
 
 	wait_event(cs->waitqueue, !cs->waiting);
@@ -972,32 +1004,6 @@ struct cardstate *gigaset_get_cs_by_id(int id)
 	return ret;
 }
 
-void gigaset_debugdrivers(void)
-{
-	unsigned long flags;
-	static struct cardstate *cs;
-	struct gigaset_driver *drv;
-	unsigned i;
-
-	spin_lock_irqsave(&driver_lock, flags);
-	list_for_each_entry(drv, &drivers, list) {
-		gig_dbg(DEBUG_DRIVER, "driver %p", drv);
-		spin_lock(&drv->lock);
-		for (i = 0; i < drv->minors; ++i) {
-			gig_dbg(DEBUG_DRIVER, "  index %u", i);
-			cs = drv->cs + i;
-			gig_dbg(DEBUG_DRIVER, "    cardstate %p", cs);
-			gig_dbg(DEBUG_DRIVER, "    flags 0x%02x", cs->flags);
-			gig_dbg(DEBUG_DRIVER, "    minor_index %u",
-				cs->minor_index);
-			gig_dbg(DEBUG_DRIVER, "    driver %p", cs->driver);
-			gig_dbg(DEBUG_DRIVER, "    i4l id %d", cs->myid);
-		}
-		spin_unlock(&drv->lock);
-	}
-	spin_unlock_irqrestore(&driver_lock, flags);
-}
-
 static struct cardstate *gigaset_get_cs_by_minor(unsigned minor)
 {
 	unsigned long flags;
@@ -1023,11 +1029,17 @@ static struct cardstate *gigaset_get_cs_by_minor(unsigned minor)
 
 struct cardstate *gigaset_get_cs_by_tty(struct tty_struct *tty)
 {
-	if (tty->index < 0 || tty->index >= tty->driver->num)
-		return NULL;
 	return gigaset_get_cs_by_minor(tty->index + tty->driver->minor_start);
 }
 
+/**
+ * gigaset_freedriver() - free all associated ressources of a driver
+ * @drv:	driver descriptor structure.
+ *
+ * Unregisters the driver from the system and deallocates the driver
+ * structure @drv and all structures referenced from it.
+ * All devices should be shut down before calling this.
+ */
 void gigaset_freedriver(struct gigaset_driver *drv)
 {
 	unsigned long flags;
@@ -1043,14 +1055,16 @@ void gigaset_freedriver(struct gigaset_driver *drv)
 }
 EXPORT_SYMBOL_GPL(gigaset_freedriver);
 
-/* gigaset_initdriver
+/**
+ * gigaset_initdriver() - initialize driver structure
+ * @minor:	First minor number
+ * @minors:	Number of minors this driver can handle
+ * @procname:	Name of the driver
+ * @devname:	Name of the device files (prefix without minor number)
+ *
  * Allocate and initialize gigaset_driver structure. Initialize interface.
- * parameters:
- *	minor		First minor number
- *	minors		Number of minors this driver can handle
- *	procname	Name of the driver
- *	devname		Name of the device files (prefix without minor number)
- * return value:
+ *
+ * Return value:
  *	Pointer to the gigaset_driver structure on success, NULL on failure.
  */
 struct gigaset_driver *gigaset_initdriver(unsigned minor, unsigned minors,
@@ -1097,12 +1111,18 @@ struct gigaset_driver *gigaset_initdriver(unsigned minor, unsigned minors,
 	return drv;
 
 error:
-	kfree(drv->cs);
 	kfree(drv);
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(gigaset_initdriver);
 
+/**
+ * gigaset_blockdriver() - block driver
+ * @drv:	driver descriptor structure.
+ *
+ * Prevents the driver from attaching new devices, in preparation for
+ * deregistration.
+ */
 void gigaset_blockdriver(struct gigaset_driver *drv)
 {
 	drv->blocked = 1;
@@ -1118,12 +1138,14 @@ static int __init gigaset_init_module(void)
 	if (gigaset_debuglevel == 1)
 		gigaset_debuglevel = DEBUG_DEFAULT;
 
-	pr_info(DRIVER_DESC "\n");
+	pr_info(DRIVER_DESC DRIVER_DESC_DEBUG "\n");
+	gigaset_isdn_regdrv();
 	return 0;
 }
 
 static void __exit gigaset_exit_module(void)
 {
+	gigaset_isdn_unregdrv();
 }
 
 module_init(gigaset_init_module);