text: /*
   *  Linux for S/390 Lan Channel Station Network Driver
   *
   *  Copyright IBM Corp. 1999, 2009
   *  Author(s): Original Code written by
   *			DJ Barrow <djbarrow@de.ibm.com,barrow_dj@yahoo.com>
   *	       Rewritten by
   *			Frank Pavlic <fpavlic@de.ibm.com> and
   *			Martin Schwidefsky <schwidefsky@de.ibm.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2, or (at your option)
   * any later version.
   *
   * 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.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  #define KMSG_COMPONENT		"lcs"
  #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  
  #include <linux/module.h>
  #include <linux/if.h>
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/trdevice.h>
  #include <linux/fddidevice.h>
  #include <linux/inetdevice.h>
  #include <linux/in.h>
  #include <linux/igmp.h>
  #include <linux/delay.h>
  #include <linux/kthread.h>
  #include <linux/slab.h>
  #include <net/arp.h>
  #include <net/ip.h>
  
  #include <asm/debug.h>
  #include <asm/idals.h>
  #include <asm/timex.h>
  #include <linux/device.h>
  #include <asm/ccwgroup.h>
  
  #include "lcs.h"
  
  
  #if !defined(CONFIG_NET_ETHERNET) && \
      !defined(CONFIG_TR) && !defined(CONFIG_FDDI)
  #error Cannot compile lcs.c without some net devices switched on.
  #endif
  
  /**
   * initialization string for output
   */
  
  static char version[] __initdata = "LCS driver";
  
  /**
    * the root device for lcs group devices
    */
  static struct device *lcs_root_dev;
  
  /**
   * Some prototypes.
   */
  static void lcs_tasklet(unsigned long);
  static void lcs_start_kernel_thread(struct work_struct *);
  static void lcs_get_frames_cb(struct lcs_channel *, struct lcs_buffer *);
  #ifdef CONFIG_IP_MULTICAST
  static int lcs_send_delipm(struct lcs_card *, struct lcs_ipm_list *);
  #endif /* CONFIG_IP_MULTICAST */
  static int lcs_recovery(void *ptr);
  
  /**
   * Debug Facility Stuff
   */
  static char debug_buffer[255];
  static debug_info_t *lcs_dbf_setup;
  static debug_info_t *lcs_dbf_trace;
  
  /**
   *  LCS Debug Facility functions
   */
  static void
  lcs_unregister_debug_facility(void)
  {
  	if (lcs_dbf_setup)
  		debug_unregister(lcs_dbf_setup);
  	if (lcs_dbf_trace)
  		debug_unregister(lcs_dbf_trace);
  }
  
  static int
  lcs_register_debug_facility(void)
  {
  	lcs_dbf_setup = debug_register("lcs_setup", 2, 1, 8);
  	lcs_dbf_trace = debug_register("lcs_trace", 4, 1, 8);
  	if (lcs_dbf_setup == NULL || lcs_dbf_trace == NULL) {
  		pr_err("Not enough memory for debug facility.\n");
  		lcs_unregister_debug_facility();
  		return -ENOMEM;
  	}
  	debug_register_view(lcs_dbf_setup, &debug_hex_ascii_view);
  	debug_set_level(lcs_dbf_setup, 2);
  	debug_register_view(lcs_dbf_trace, &debug_hex_ascii_view);
  	debug_set_level(lcs_dbf_trace, 2);
  	return 0;
  }
  
  /**
   * Allocate io buffers.
   */
  static int
  lcs_alloc_channel(struct lcs_channel *channel)
  {
  	int cnt;
  
  	LCS_DBF_TEXT(2, setup, "ichalloc");
  	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
  		/* alloc memory fo iobuffer */
  		channel->iob[cnt].data =
  			kzalloc(LCS_IOBUFFERSIZE, GFP_DMA | GFP_KERNEL);
  		if (channel->iob[cnt].data == NULL)
  			break;
  		channel->iob[cnt].state = LCS_BUF_STATE_EMPTY;
  	}
  	if (cnt < LCS_NUM_BUFFS) {
  		/* Not all io buffers could be allocated. */
  		LCS_DBF_TEXT(2, setup, "echalloc");
  		while (cnt-- > 0)
  			kfree(channel->iob[cnt].data);
  		return -ENOMEM;
  	}
  	return 0;
  }
  
  /**
   * Free io buffers.
   */
  static void
  lcs_free_channel(struct lcs_channel *channel)
  {
  	int cnt;
  
  	LCS_DBF_TEXT(2, setup, "ichfree");
  	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
  		kfree(channel->iob[cnt].data);
  		channel->iob[cnt].data = NULL;
  	}
  }
  
  /*
   * Cleanup channel.
   */
  static void
  lcs_cleanup_channel(struct lcs_channel *channel)
  {
  	LCS_DBF_TEXT(3, setup, "cleanch");
  	/* Kill write channel tasklets. */
  	tasklet_kill(&channel->irq_tasklet);
  	/* Free channel buffers. */
  	lcs_free_channel(channel);
  }
  
  /**
   * LCS free memory for card and channels.
   */
  static void
  lcs_free_card(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(2, setup, "remcard");
  	LCS_DBF_HEX(2, setup, &card, sizeof(void*));
  	kfree(card);
  }
  
  /**
   * LCS alloc memory for card and channels
   */
  static struct lcs_card *
  lcs_alloc_card(void)
  {
  	struct lcs_card *card;
  	int rc;
  
  	LCS_DBF_TEXT(2, setup, "alloclcs");
  
  	card = kzalloc(sizeof(struct lcs_card), GFP_KERNEL | GFP_DMA);
  	if (card == NULL)
  		return NULL;
  	card->lan_type = LCS_FRAME_TYPE_AUTO;
  	card->pkt_seq = 0;
  	card->lancmd_timeout = LCS_LANCMD_TIMEOUT_DEFAULT;
  	/* Allocate io buffers for the read channel. */
  	rc = lcs_alloc_channel(&card->read);
  	if (rc){
  		LCS_DBF_TEXT(2, setup, "iccwerr");
  		lcs_free_card(card);
  		return NULL;
  	}
  	/* Allocate io buffers for the write channel. */
  	rc = lcs_alloc_channel(&card->write);
  	if (rc) {
  		LCS_DBF_TEXT(2, setup, "iccwerr");
  		lcs_cleanup_channel(&card->read);
  		lcs_free_card(card);
  		return NULL;
  	}
  
  #ifdef CONFIG_IP_MULTICAST
  	INIT_LIST_HEAD(&card->ipm_list);
  #endif
  	LCS_DBF_HEX(2, setup, &card, sizeof(void*));
  	return card;
  }
  
  /*
   * Setup read channel.
   */
  static void
  lcs_setup_read_ccws(struct lcs_card *card)
  {
  	int cnt;
  
  	LCS_DBF_TEXT(2, setup, "ireadccw");
  	/* Setup read ccws. */
  	memset(card->read.ccws, 0, sizeof (struct ccw1) * (LCS_NUM_BUFFS + 1));
  	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
  		card->read.ccws[cnt].cmd_code = LCS_CCW_READ;
  		card->read.ccws[cnt].count = LCS_IOBUFFERSIZE;
  		card->read.ccws[cnt].flags =
  			CCW_FLAG_CC | CCW_FLAG_SLI | CCW_FLAG_PCI;
  		/*
  		 * Note: we have allocated the buffer with GFP_DMA, so
  		 * we do not need to do set_normalized_cda.
  		 */
  		card->read.ccws[cnt].cda =
  			(__u32) __pa(card->read.iob[cnt].data);
  		((struct lcs_header *)
  		 card->read.iob[cnt].data)->offset = LCS_ILLEGAL_OFFSET;
  		card->read.iob[cnt].callback = lcs_get_frames_cb;
  		card->read.iob[cnt].state = LCS_BUF_STATE_READY;
  		card->read.iob[cnt].count = LCS_IOBUFFERSIZE;
  	}
  	card->read.ccws[0].flags &= ~CCW_FLAG_PCI;
  	card->read.ccws[LCS_NUM_BUFFS - 1].flags &= ~CCW_FLAG_PCI;
  	card->read.ccws[LCS_NUM_BUFFS - 1].flags |= CCW_FLAG_SUSPEND;
  	/* Last ccw is a tic (transfer in channel). */
  	card->read.ccws[LCS_NUM_BUFFS].cmd_code = LCS_CCW_TRANSFER;
  	card->read.ccws[LCS_NUM_BUFFS].cda =
  		(__u32) __pa(card->read.ccws);
  	/* Setg initial state of the read channel. */
  	card->read.state = LCS_CH_STATE_INIT;
  
  	card->read.io_idx = 0;
  	card->read.buf_idx = 0;
  }
  
  static void
  lcs_setup_read(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(3, setup, "initread");
  
  	lcs_setup_read_ccws(card);
  	/* Initialize read channel tasklet. */
  	card->read.irq_tasklet.data = (unsigned long) &card->read;
  	card->read.irq_tasklet.func = lcs_tasklet;
  	/* Initialize waitqueue. */
  	init_waitqueue_head(&card->read.wait_q);
  }
  
  /*
   * Setup write channel.
   */
  static void
  lcs_setup_write_ccws(struct lcs_card *card)
  {
  	int cnt;
  
  	LCS_DBF_TEXT(3, setup, "iwritccw");
  	/* Setup write ccws. */
  	memset(card->write.ccws, 0, sizeof(struct ccw1) * LCS_NUM_BUFFS + 1);
  	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
  		card->write.ccws[cnt].cmd_code = LCS_CCW_WRITE;
  		card->write.ccws[cnt].count = 0;
  		card->write.ccws[cnt].flags =
  			CCW_FLAG_SUSPEND | CCW_FLAG_CC | CCW_FLAG_SLI;
  		/*
  		 * Note: we have allocated the buffer with GFP_DMA, so
  		 * we do not need to do set_normalized_cda.
  		 */
  		card->write.ccws[cnt].cda =
  			(__u32) __pa(card->write.iob[cnt].data);
  	}
  	/* Last ccw is a tic (transfer in channel). */
  	card->write.ccws[LCS_NUM_BUFFS].cmd_code = LCS_CCW_TRANSFER;
  	card->write.ccws[LCS_NUM_BUFFS].cda =
  		(__u32) __pa(card->write.ccws);
  	/* Set initial state of the write channel. */
  	card->read.state = LCS_CH_STATE_INIT;
  
  	card->write.io_idx = 0;
  	card->write.buf_idx = 0;
  }
  
  static void
  lcs_setup_write(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(3, setup, "initwrit");
  
  	lcs_setup_write_ccws(card);
  	/* Initialize write channel tasklet. */
  	card->write.irq_tasklet.data = (unsigned long) &card->write;
  	card->write.irq_tasklet.func = lcs_tasklet;
  	/* Initialize waitqueue. */
  	init_waitqueue_head(&card->write.wait_q);
  }
  
  static void
  lcs_set_allowed_threads(struct lcs_card *card, unsigned long threads)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&card->mask_lock, flags);
  	card->thread_allowed_mask = threads;
  	spin_unlock_irqrestore(&card->mask_lock, flags);
  	wake_up(&card->wait_q);
  }
  static inline int
  lcs_threads_running(struct lcs_card *card, unsigned long threads)
  {
          unsigned long flags;
          int rc = 0;
  
  	spin_lock_irqsave(&card->mask_lock, flags);
          rc = (card->thread_running_mask & threads);
  	spin_unlock_irqrestore(&card->mask_lock, flags);
          return rc;
  }
  
  static int
  lcs_wait_for_threads(struct lcs_card *card, unsigned long threads)
  {
          return wait_event_interruptible(card->wait_q,
                          lcs_threads_running(card, threads) == 0);
  }
  
  static inline int
  lcs_set_thread_start_bit(struct lcs_card *card, unsigned long thread)
  {
          unsigned long flags;
  
  	spin_lock_irqsave(&card->mask_lock, flags);
          if ( !(card->thread_allowed_mask & thread) ||
                (card->thread_start_mask & thread) ) {
                  spin_unlock_irqrestore(&card->mask_lock, flags);
                  return -EPERM;
          }
          card->thread_start_mask |= thread;
  	spin_unlock_irqrestore(&card->mask_lock, flags);
          return 0;
  }
  
  static void
  lcs_clear_thread_running_bit(struct lcs_card *card, unsigned long thread)
  {
          unsigned long flags;
  
  	spin_lock_irqsave(&card->mask_lock, flags);
          card->thread_running_mask &= ~thread;
  	spin_unlock_irqrestore(&card->mask_lock, flags);
          wake_up(&card->wait_q);
  }
  
  static inline int
  __lcs_do_run_thread(struct lcs_card *card, unsigned long thread)
  {
          unsigned long flags;
          int rc = 0;
  
  	spin_lock_irqsave(&card->mask_lock, flags);
          if (card->thread_start_mask & thread){
                  if ((card->thread_allowed_mask & thread) &&
                      !(card->thread_running_mask & thread)){
                          rc = 1;
                          card->thread_start_mask &= ~thread;
                          card->thread_running_mask |= thread;
                  } else
                          rc = -EPERM;
          }
  	spin_unlock_irqrestore(&card->mask_lock, flags);
          return rc;
  }
  
  static int
  lcs_do_run_thread(struct lcs_card *card, unsigned long thread)
  {
          int rc = 0;
          wait_event(card->wait_q,
                     (rc = __lcs_do_run_thread(card, thread)) >= 0);
          return rc;
  }
  
  static int
  lcs_do_start_thread(struct lcs_card *card, unsigned long thread)
  {
          unsigned long flags;
          int rc = 0;
  
  	spin_lock_irqsave(&card->mask_lock, flags);
          LCS_DBF_TEXT_(4, trace, "  %02x%02x%02x",
                          (u8) card->thread_start_mask,
                          (u8) card->thread_allowed_mask,
                          (u8) card->thread_running_mask);
          rc = (card->thread_start_mask & thread);
  	spin_unlock_irqrestore(&card->mask_lock, flags);
          return rc;
  }
  
  /**
   * Initialize channels,card and state machines.
   */
  static void
  lcs_setup_card(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(2, setup, "initcard");
  	LCS_DBF_HEX(2, setup, &card, sizeof(void*));
  
  	lcs_setup_read(card);
  	lcs_setup_write(card);
  	/* Set cards initial state. */
  	card->state = DEV_STATE_DOWN;
  	card->tx_buffer = NULL;
  	card->tx_emitted = 0;
  
  	init_waitqueue_head(&card->wait_q);
  	spin_lock_init(&card->lock);
  	spin_lock_init(&card->ipm_lock);
  	spin_lock_init(&card->mask_lock);
  #ifdef CONFIG_IP_MULTICAST
  	INIT_LIST_HEAD(&card->ipm_list);
  #endif
  	INIT_LIST_HEAD(&card->lancmd_waiters);
  }
  
  static inline void
  lcs_clear_multicast_list(struct lcs_card *card)
  {
  #ifdef	CONFIG_IP_MULTICAST
  	struct lcs_ipm_list *ipm;
  	unsigned long flags;
  
  	/* Free multicast list. */
  	LCS_DBF_TEXT(3, setup, "clmclist");
  	spin_lock_irqsave(&card->ipm_lock, flags);
  	while (!list_empty(&card->ipm_list)){
  		ipm = list_entry(card->ipm_list.next,
  				 struct lcs_ipm_list, list);
  		list_del(&ipm->list);
  		if (ipm->ipm_state != LCS_IPM_STATE_SET_REQUIRED){
  			spin_unlock_irqrestore(&card->ipm_lock, flags);
  			lcs_send_delipm(card, ipm);
  			spin_lock_irqsave(&card->ipm_lock, flags);
  		}
  		kfree(ipm);
  	}
  	spin_unlock_irqrestore(&card->ipm_lock, flags);
  #endif
  }
  /**
   * Cleanup channels,card and state machines.
   */
  static void
  lcs_cleanup_card(struct lcs_card *card)
  {
  
  	LCS_DBF_TEXT(3, setup, "cleancrd");
  	LCS_DBF_HEX(2,setup,&card,sizeof(void*));
  
  	if (card->dev != NULL)
  		free_netdev(card->dev);
  	/* Cleanup channels. */
  	lcs_cleanup_channel(&card->write);
  	lcs_cleanup_channel(&card->read);
  }
  
  /**
   * Start channel.
   */
  static int
  lcs_start_channel(struct lcs_channel *channel)
  {
  	unsigned long flags;
  	int rc;
  
  	LCS_DBF_TEXT_(4, trace,"ssch%s", dev_name(&channel->ccwdev->dev));
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	rc = ccw_device_start(channel->ccwdev,
  			      channel->ccws + channel->io_idx, 0, 0,
  			      DOIO_DENY_PREFETCH | DOIO_ALLOW_SUSPEND);
  	if (rc == 0)
  		channel->state = LCS_CH_STATE_RUNNING;
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  	if (rc) {
  		LCS_DBF_TEXT_(4,trace,"essh%s",
  			      dev_name(&channel->ccwdev->dev));
  		dev_err(&channel->ccwdev->dev,
  			"Starting an LCS device resulted in an error,"
  			" rc=%d!\n", rc);
  	}
  	return rc;
  }
  
  static int
  lcs_clear_channel(struct lcs_channel *channel)
  {
  	unsigned long flags;
  	int rc;
  
  	LCS_DBF_TEXT(4,trace,"clearch");
  	LCS_DBF_TEXT_(4, trace, "%s", dev_name(&channel->ccwdev->dev));
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	rc = ccw_device_clear(channel->ccwdev, (addr_t) channel);
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  	if (rc) {
  		LCS_DBF_TEXT_(4, trace, "ecsc%s",
  			      dev_name(&channel->ccwdev->dev));
  		return rc;
  	}
  	wait_event(channel->wait_q, (channel->state == LCS_CH_STATE_CLEARED));
  	channel->state = LCS_CH_STATE_STOPPED;
  	return rc;
  }
  
  
  /**
   * Stop channel.
   */
  static int
  lcs_stop_channel(struct lcs_channel *channel)
  {
  	unsigned long flags;
  	int rc;
  
  	if (channel->state == LCS_CH_STATE_STOPPED)
  		return 0;
  	LCS_DBF_TEXT(4,trace,"haltsch");
  	LCS_DBF_TEXT_(4, trace, "%s", dev_name(&channel->ccwdev->dev));
  	channel->state = LCS_CH_STATE_INIT;
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	rc = ccw_device_halt(channel->ccwdev, (addr_t) channel);
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  	if (rc) {
  		LCS_DBF_TEXT_(4, trace, "ehsc%s",
  			      dev_name(&channel->ccwdev->dev));
  		return rc;
  	}
  	/* Asynchronous halt initialted. Wait for its completion. */
  	wait_event(channel->wait_q, (channel->state == LCS_CH_STATE_HALTED));
  	lcs_clear_channel(channel);
  	return 0;
  }
  
  /**
   * start read and write channel
   */
  static int
  lcs_start_channels(struct lcs_card *card)
  {
  	int rc;
  
  	LCS_DBF_TEXT(2, trace, "chstart");
  	/* start read channel */
  	rc = lcs_start_channel(&card->read);
  	if (rc)
  		return rc;
  	/* start write channel */
  	rc = lcs_start_channel(&card->write);
  	if (rc)
  		lcs_stop_channel(&card->read);
  	return rc;
  }
  
  /**
   * stop read and write channel
   */
  static int
  lcs_stop_channels(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(2, trace, "chhalt");
  	lcs_stop_channel(&card->read);
  	lcs_stop_channel(&card->write);
  	return 0;
  }
  
  /**
   * Get empty buffer.
   */
  static struct lcs_buffer *
  __lcs_get_buffer(struct lcs_channel *channel)
  {
  	int index;
  
  	LCS_DBF_TEXT(5, trace, "_getbuff");
  	index = channel->io_idx;
  	do {
  		if (channel->iob[index].state == LCS_BUF_STATE_EMPTY) {
  			channel->iob[index].state = LCS_BUF_STATE_LOCKED;
  			return channel->iob + index;
  		}
  		index = (index + 1) & (LCS_NUM_BUFFS - 1);
  	} while (index != channel->io_idx);
  	return NULL;
  }
  
  static struct lcs_buffer *
  lcs_get_buffer(struct lcs_channel *channel)
  {
  	struct lcs_buffer *buffer;
  	unsigned long flags;
  
  	LCS_DBF_TEXT(5, trace, "getbuff");
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	buffer = __lcs_get_buffer(channel);
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  	return buffer;
  }
  
  /**
   * Resume channel program if the channel is suspended.
   */
  static int
  __lcs_resume_channel(struct lcs_channel *channel)
  {
  	int rc;
  
  	if (channel->state != LCS_CH_STATE_SUSPENDED)
  		return 0;
  	if (channel->ccws[channel->io_idx].flags & CCW_FLAG_SUSPEND)
  		return 0;
  	LCS_DBF_TEXT_(5, trace, "rsch%s", dev_name(&channel->ccwdev->dev));
  	rc = ccw_device_resume(channel->ccwdev);
  	if (rc) {
  		LCS_DBF_TEXT_(4, trace, "ersc%s",
  			      dev_name(&channel->ccwdev->dev));
  		dev_err(&channel->ccwdev->dev,
  			"Sending data from the LCS device to the LAN failed"
  			" with rc=%d\n",rc);
  	} else
  		channel->state = LCS_CH_STATE_RUNNING;
  	return rc;
  
  }
  
  /**
   * Make a buffer ready for processing.
   */
  static inline void
  __lcs_ready_buffer_bits(struct lcs_channel *channel, int index)
  {
  	int prev, next;
  
  	LCS_DBF_TEXT(5, trace, "rdybits");
  	prev = (index - 1) & (LCS_NUM_BUFFS - 1);
  	next = (index + 1) & (LCS_NUM_BUFFS - 1);
  	/* Check if we may clear the suspend bit of this buffer. */
  	if (channel->ccws[next].flags & CCW_FLAG_SUSPEND) {
  		/* Check if we have to set the PCI bit. */
  		if (!(channel->ccws[prev].flags & CCW_FLAG_SUSPEND))
  			/* Suspend bit of the previous buffer is not set. */
  			channel->ccws[index].flags |= CCW_FLAG_PCI;
  		/* Suspend bit of the next buffer is set. */
  		channel->ccws[index].flags &= ~CCW_FLAG_SUSPEND;
  	}
  }
  
  static int
  lcs_ready_buffer(struct lcs_channel *channel, struct lcs_buffer *buffer)
  {
  	unsigned long flags;
  	int index, rc;
  
  	LCS_DBF_TEXT(5, trace, "rdybuff");
  	BUG_ON(buffer->state != LCS_BUF_STATE_LOCKED &&
  	       buffer->state != LCS_BUF_STATE_PROCESSED);
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	buffer->state = LCS_BUF_STATE_READY;
  	index = buffer - channel->iob;
  	/* Set length. */
  	channel->ccws[index].count = buffer->count;
  	/* Check relevant PCI/suspend bits. */
  	__lcs_ready_buffer_bits(channel, index);
  	rc = __lcs_resume_channel(channel);
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  	return rc;
  }
  
  /**
   * Mark the buffer as processed. Take care of the suspend bit
   * of the previous buffer. This function is called from
   * interrupt context, so the lock must not be taken.
   */
  static int
  __lcs_processed_buffer(struct lcs_channel *channel, struct lcs_buffer *buffer)
  {
  	int index, prev, next;
  
  	LCS_DBF_TEXT(5, trace, "prcsbuff");
  	BUG_ON(buffer->state != LCS_BUF_STATE_READY);
  	buffer->state = LCS_BUF_STATE_PROCESSED;
  	index = buffer - channel->iob;
  	prev = (index - 1) & (LCS_NUM_BUFFS - 1);
  	next = (index + 1) & (LCS_NUM_BUFFS - 1);
  	/* Set the suspend bit and clear the PCI bit of this buffer. */
  	channel->ccws[index].flags |= CCW_FLAG_SUSPEND;
  	channel->ccws[index].flags &= ~CCW_FLAG_PCI;
  	/* Check the suspend bit of the previous buffer. */
  	if (channel->iob[prev].state == LCS_BUF_STATE_READY) {
  		/*
  		 * Previous buffer is in state ready. It might have
  		 * happened in lcs_ready_buffer that the suspend bit
  		 * has not been cleared to avoid an endless loop.
  		 * Do it now.
  		 */
  		__lcs_ready_buffer_bits(channel, prev);
  	}
  	/* Clear PCI bit of next buffer. */
  	channel->ccws[next].flags &= ~CCW_FLAG_PCI;
  	return __lcs_resume_channel(channel);
  }
  
  /**
   * Put a processed buffer back to state empty.
   */
  static void
  lcs_release_buffer(struct lcs_channel *channel, struct lcs_buffer *buffer)
  {
  	unsigned long flags;
  
  	LCS_DBF_TEXT(5, trace, "relbuff");
  	BUG_ON(buffer->state != LCS_BUF_STATE_LOCKED &&
  	       buffer->state != LCS_BUF_STATE_PROCESSED);
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	buffer->state = LCS_BUF_STATE_EMPTY;
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  }
  
  /**
   * Get buffer for a lan command.
   */
  static struct lcs_buffer *
  lcs_get_lancmd(struct lcs_card *card, int count)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(4, trace, "getlncmd");
  	/* Get buffer and wait if none is available. */
  	wait_event(card->write.wait_q,
  		   ((buffer = lcs_get_buffer(&card->write)) != NULL));
  	count += sizeof(struct lcs_header);
  	*(__u16 *)(buffer->data + count) = 0;
  	buffer->count = count + sizeof(__u16);
  	buffer->callback = lcs_release_buffer;
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->offset = count;
  	cmd->type = LCS_FRAME_TYPE_CONTROL;
  	cmd->slot = 0;
  	return buffer;
  }
  
  
  static void
  lcs_get_reply(struct lcs_reply *reply)
  {
  	WARN_ON(atomic_read(&reply->refcnt) <= 0);
  	atomic_inc(&reply->refcnt);
  }
  
  static void
  lcs_put_reply(struct lcs_reply *reply)
  {
          WARN_ON(atomic_read(&reply->refcnt) <= 0);
          if (atomic_dec_and_test(&reply->refcnt)) {
  		kfree(reply);
  	}
  
  }
  
  static struct lcs_reply *
  lcs_alloc_reply(struct lcs_cmd *cmd)
  {
  	struct lcs_reply *reply;
  
  	LCS_DBF_TEXT(4, trace, "getreply");
  
  	reply = kzalloc(sizeof(struct lcs_reply), GFP_ATOMIC);
  	if (!reply)
  		return NULL;
  	atomic_set(&reply->refcnt,1);
  	reply->sequence_no = cmd->sequence_no;
  	reply->received = 0;
  	reply->rc = 0;
  	init_waitqueue_head(&reply->wait_q);
  
  	return reply;
  }
  
  /**
   * Notifier function for lancmd replies. Called from read irq.
   */
  static void
  lcs_notify_lancmd_waiters(struct lcs_card *card, struct lcs_cmd *cmd)
  {
  	struct list_head *l, *n;
  	struct lcs_reply *reply;
  
  	LCS_DBF_TEXT(4, trace, "notiwait");
  	spin_lock(&card->lock);
  	list_for_each_safe(l, n, &card->lancmd_waiters) {
  		reply = list_entry(l, struct lcs_reply, list);
  		if (reply->sequence_no == cmd->sequence_no) {
  			lcs_get_reply(reply);
  			list_del_init(&reply->list);
  			if (reply->callback != NULL)
  				reply->callback(card, cmd);
  			reply->received = 1;
  			reply->rc = cmd->return_code;
  			wake_up(&reply->wait_q);
  			lcs_put_reply(reply);
  			break;
  		}
  	}
  	spin_unlock(&card->lock);
  }
  
  /**
   * Emit buffer of a lan comand.
   */
  static void
  lcs_lancmd_timeout(unsigned long data)
  {
  	struct lcs_reply *reply, *list_reply, *r;
  	unsigned long flags;
  
  	LCS_DBF_TEXT(4, trace, "timeout");
  	reply = (struct lcs_reply *) data;
  	spin_lock_irqsave(&reply->card->lock, flags);
  	list_for_each_entry_safe(list_reply, r,
  				 &reply->card->lancmd_waiters,list) {
  		if (reply == list_reply) {
  			lcs_get_reply(reply);
  			list_del_init(&reply->list);
  			spin_unlock_irqrestore(&reply->card->lock, flags);
  			reply->received = 1;
  			reply->rc = -ETIME;
  			wake_up(&reply->wait_q);
  			lcs_put_reply(reply);
  			return;
  		}
  	}
  	spin_unlock_irqrestore(&reply->card->lock, flags);
  }
  
  static int
  lcs_send_lancmd(struct lcs_card *card, struct lcs_buffer *buffer,
  		void (*reply_callback)(struct lcs_card *, struct lcs_cmd *))
  {
  	struct lcs_reply *reply;
  	struct lcs_cmd *cmd;
  	struct timer_list timer;
  	unsigned long flags;
  	int rc;
  
  	LCS_DBF_TEXT(4, trace, "sendcmd");
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->return_code = 0;
  	cmd->sequence_no = card->sequence_no++;
  	reply = lcs_alloc_reply(cmd);
  	if (!reply)
  		return -ENOMEM;
  	reply->callback = reply_callback;
  	reply->card = card;
  	spin_lock_irqsave(&card->lock, flags);
  	list_add_tail(&reply->list, &card->lancmd_waiters);
  	spin_unlock_irqrestore(&card->lock, flags);
  
  	buffer->callback = lcs_release_buffer;
  	rc = lcs_ready_buffer(&card->write, buffer);
  	if (rc)
  		return rc;
  	init_timer_on_stack(&timer);
  	timer.function = lcs_lancmd_timeout;
  	timer.data = (unsigned long) reply;
  	timer.expires = jiffies + HZ*card->lancmd_timeout;
  	add_timer(&timer);
  	wait_event(reply->wait_q, reply->received);
  	del_timer_sync(&timer);
  	LCS_DBF_TEXT_(4, trace, "rc:%d",reply->rc);
  	rc = reply->rc;
  	lcs_put_reply(reply);
  	return rc ? -EIO : 0;
  }
  
  /**
   * LCS startup command
   */
  static int
  lcs_send_startup(struct lcs_card *card, __u8 initiator)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2, trace, "startup");
  	buffer = lcs_get_lancmd(card, LCS_STD_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_STARTUP;
  	cmd->initiator = initiator;
  	cmd->cmd.lcs_startup.buff_size = LCS_IOBUFFERSIZE;
  	return lcs_send_lancmd(card, buffer, NULL);
  }
  
  /**
   * LCS shutdown command
   */
  static int
  lcs_send_shutdown(struct lcs_card *card)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2, trace, "shutdown");
  	buffer = lcs_get_lancmd(card, LCS_STD_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_SHUTDOWN;
  	cmd->initiator = LCS_INITIATOR_TCPIP;
  	return lcs_send_lancmd(card, buffer, NULL);
  }
  
  /**
   * LCS lanstat command
   */
  static void
  __lcs_lanstat_cb(struct lcs_card *card, struct lcs_cmd *cmd)
  {
  	LCS_DBF_TEXT(2, trace, "statcb");
  	memcpy(card->mac, cmd->cmd.lcs_lanstat_cmd.mac_addr, LCS_MAC_LENGTH);
  }
  
  static int
  lcs_send_lanstat(struct lcs_card *card)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2,trace, "cmdstat");
  	buffer = lcs_get_lancmd(card, LCS_STD_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	/* Setup lanstat command. */
  	cmd->cmd_code = LCS_CMD_LANSTAT;
  	cmd->initiator = LCS_INITIATOR_TCPIP;
  	cmd->cmd.lcs_std_cmd.lan_type = card->lan_type;
  	cmd->cmd.lcs_std_cmd.portno = card->portno;
  	return lcs_send_lancmd(card, buffer, __lcs_lanstat_cb);
  }
  
  /**
   * send stoplan command
   */
  static int
  lcs_send_stoplan(struct lcs_card *card, __u8 initiator)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2, trace, "cmdstpln");
  	buffer = lcs_get_lancmd(card, LCS_STD_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_STOPLAN;
  	cmd->initiator = initiator;
  	cmd->cmd.lcs_std_cmd.lan_type = card->lan_type;
  	cmd->cmd.lcs_std_cmd.portno = card->portno;
  	return lcs_send_lancmd(card, buffer, NULL);
  }
  
  /**
   * send startlan command
   */
  static void
  __lcs_send_startlan_cb(struct lcs_card *card, struct lcs_cmd *cmd)
  {
  	LCS_DBF_TEXT(2, trace, "srtlancb");
  	card->lan_type = cmd->cmd.lcs_std_cmd.lan_type;
  	card->portno = cmd->cmd.lcs_std_cmd.portno;
  }
  
  static int
  lcs_send_startlan(struct lcs_card *card, __u8 initiator)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2, trace, "cmdstaln");
  	buffer = lcs_get_lancmd(card, LCS_STD_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_STARTLAN;
  	cmd->initiator = initiator;
  	cmd->cmd.lcs_std_cmd.lan_type = card->lan_type;
  	cmd->cmd.lcs_std_cmd.portno = card->portno;
  	return lcs_send_lancmd(card, buffer, __lcs_send_startlan_cb);
  }
  
  #ifdef CONFIG_IP_MULTICAST
  /**
   * send setipm command (Multicast)
   */
  static int
  lcs_send_setipm(struct lcs_card *card,struct lcs_ipm_list *ipm_list)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2, trace, "cmdsetim");
  	buffer = lcs_get_lancmd(card, LCS_MULTICAST_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_SETIPM;
  	cmd->initiator = LCS_INITIATOR_TCPIP;
  	cmd->cmd.lcs_qipassist.lan_type = card->lan_type;
  	cmd->cmd.lcs_qipassist.portno = card->portno;
  	cmd->cmd.lcs_qipassist.version = 4;
  	cmd->cmd.lcs_qipassist.num_ip_pairs = 1;
  	memcpy(cmd->cmd.lcs_qipassist.lcs_ipass_ctlmsg.ip_mac_pair,
  	       &ipm_list->ipm, sizeof (struct lcs_ip_mac_pair));
  	LCS_DBF_TEXT_(2, trace, "%x",ipm_list->ipm.ip_addr);
  	return lcs_send_lancmd(card, buffer, NULL);
  }
  
  /**
   * send delipm command (Multicast)
   */
  static int
  lcs_send_delipm(struct lcs_card *card,struct lcs_ipm_list *ipm_list)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  
  	LCS_DBF_TEXT(2, trace, "cmddelim");
  	buffer = lcs_get_lancmd(card, LCS_MULTICAST_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_DELIPM;
  	cmd->initiator = LCS_INITIATOR_TCPIP;
  	cmd->cmd.lcs_qipassist.lan_type = card->lan_type;
  	cmd->cmd.lcs_qipassist.portno = card->portno;
  	cmd->cmd.lcs_qipassist.version = 4;
  	cmd->cmd.lcs_qipassist.num_ip_pairs = 1;
  	memcpy(cmd->cmd.lcs_qipassist.lcs_ipass_ctlmsg.ip_mac_pair,
  	       &ipm_list->ipm, sizeof (struct lcs_ip_mac_pair));
  	LCS_DBF_TEXT_(2, trace, "%x",ipm_list->ipm.ip_addr);
  	return lcs_send_lancmd(card, buffer, NULL);
  }
  
  /**
   * check if multicast is supported by LCS
   */
  static void
  __lcs_check_multicast_cb(struct lcs_card *card, struct lcs_cmd *cmd)
  {
  	LCS_DBF_TEXT(2, trace, "chkmccb");
  	card->ip_assists_supported =
  		cmd->cmd.lcs_qipassist.ip_assists_supported;
  	card->ip_assists_enabled =
  		cmd->cmd.lcs_qipassist.ip_assists_enabled;
  }
  
  static int
  lcs_check_multicast_support(struct lcs_card *card)
  {
  	struct lcs_buffer *buffer;
  	struct lcs_cmd *cmd;
  	int rc;
  
  	LCS_DBF_TEXT(2, trace, "cmdqipa");
  	/* Send query ipassist. */
  	buffer = lcs_get_lancmd(card, LCS_STD_CMD_SIZE);
  	cmd = (struct lcs_cmd *) buffer->data;
  	cmd->cmd_code = LCS_CMD_QIPASSIST;
  	cmd->initiator = LCS_INITIATOR_TCPIP;
  	cmd->cmd.lcs_qipassist.lan_type = card->lan_type;
  	cmd->cmd.lcs_qipassist.portno = card->portno;
  	cmd->cmd.lcs_qipassist.version = 4;
  	cmd->cmd.lcs_qipassist.num_ip_pairs = 1;
  	rc = lcs_send_lancmd(card, buffer, __lcs_check_multicast_cb);
  	if (rc != 0) {
  		pr_err("Query IPAssist failed. Assuming unsupported!\n");
  		return -EOPNOTSUPP;
  	}
  	if (card->ip_assists_supported & LCS_IPASS_MULTICAST_SUPPORT)
  		return 0;
  	return -EOPNOTSUPP;
  }
  
  /**
   * set or del multicast address on LCS card
   */
  static void
  lcs_fix_multicast_list(struct lcs_card *card)
  {
  	struct list_head failed_list;
  	struct lcs_ipm_list *ipm, *tmp;
  	unsigned long flags;
  	int rc;
  
  	LCS_DBF_TEXT(4,trace, "fixipm");
  	INIT_LIST_HEAD(&failed_list);
  	spin_lock_irqsave(&card->ipm_lock, flags);
  list_modified:
  	list_for_each_entry_safe(ipm, tmp, &card->ipm_list, list){
  		switch (ipm->ipm_state) {
  		case LCS_IPM_STATE_SET_REQUIRED:
  			/* del from ipm_list so noone else can tamper with
  			 * this entry */
  			list_del_init(&ipm->list);
  			spin_unlock_irqrestore(&card->ipm_lock, flags);
  			rc = lcs_send_setipm(card, ipm);
  			spin_lock_irqsave(&card->ipm_lock, flags);
  			if (rc) {
  				pr_info("Adding multicast address failed."
  					" Table possibly full!\n");
  				/* store ipm in failed list -> will be added
  				 * to ipm_list again, so a retry will be done
  				 * during the next call of this function */
  				list_add_tail(&ipm->list, &failed_list);
  			} else {
  				ipm->ipm_state = LCS_IPM_STATE_ON_CARD;
  				/* re-insert into ipm_list */
  				list_add_tail(&ipm->list, &card->ipm_list);
  			}
  			goto list_modified;
  		case LCS_IPM_STATE_DEL_REQUIRED:
  			list_del(&ipm->list);
  			spin_unlock_irqrestore(&card->ipm_lock, flags);
  			lcs_send_delipm(card, ipm);
  			spin_lock_irqsave(&card->ipm_lock, flags);
  			kfree(ipm);
  			goto list_modified;
  		case LCS_IPM_STATE_ON_CARD:
  			break;
  		}
  	}
  	/* re-insert all entries from the failed_list into ipm_list */
  	list_for_each_entry_safe(ipm, tmp, &failed_list, list)
  		list_move_tail(&ipm->list, &card->ipm_list);
  
  	spin_unlock_irqrestore(&card->ipm_lock, flags);
  }
  
  /**
   * get mac address for the relevant Multicast address
   */
  static void
  lcs_get_mac_for_ipm(__be32 ipm, char *mac, struct net_device *dev)
  {
  	LCS_DBF_TEXT(4,trace, "getmac");
  	if (dev->type == ARPHRD_IEEE802_TR)
  		ip_tr_mc_map(ipm, mac);
  	else
  		ip_eth_mc_map(ipm, mac);
  }
  
  /**
   * function called by net device to handle multicast address relevant things
   */
  static inline void
  lcs_remove_mc_addresses(struct lcs_card *card, struct in_device *in4_dev)
  {
  	struct ip_mc_list *im4;
  	struct list_head *l;
  	struct lcs_ipm_list *ipm;
  	unsigned long flags;
  	char buf[MAX_ADDR_LEN];
  
  	LCS_DBF_TEXT(4, trace, "remmclst");
  	spin_lock_irqsave(&card->ipm_lock, flags);
  	list_for_each(l, &card->ipm_list) {
  		ipm = list_entry(l, struct lcs_ipm_list, list);
  		for (im4 = in4_dev->mc_list; im4 != NULL; im4 = im4->next) {
  			lcs_get_mac_for_ipm(im4->multiaddr, buf, card->dev);
  			if ( (ipm->ipm.ip_addr == im4->multiaddr) &&
  			     (memcmp(buf, &ipm->ipm.mac_addr,
  				     LCS_MAC_LENGTH) == 0) )
  				break;
  		}
  		if (im4 == NULL)
  			ipm->ipm_state = LCS_IPM_STATE_DEL_REQUIRED;
  	}
  	spin_unlock_irqrestore(&card->ipm_lock, flags);
  }
  
  static inline struct lcs_ipm_list *
  lcs_check_addr_entry(struct lcs_card *card, struct ip_mc_list *im4, char *buf)
  {
  	struct lcs_ipm_list *tmp, *ipm = NULL;
  	struct list_head *l;
  	unsigned long flags;
  
  	LCS_DBF_TEXT(4, trace, "chkmcent");
  	spin_lock_irqsave(&card->ipm_lock, flags);
  	list_for_each(l, &card->ipm_list) {
  		tmp = list_entry(l, struct lcs_ipm_list, list);
  		if ( (tmp->ipm.ip_addr == im4->multiaddr) &&
  		     (memcmp(buf, &tmp->ipm.mac_addr,
  			     LCS_MAC_LENGTH) == 0) ) {
  			ipm = tmp;
  			break;
  		}
  	}
  	spin_unlock_irqrestore(&card->ipm_lock, flags);
  	return ipm;
  }
  
  static inline void
  lcs_set_mc_addresses(struct lcs_card *card, struct in_device *in4_dev)
  {
  
  	struct ip_mc_list *im4;
  	struct lcs_ipm_list *ipm;
  	char buf[MAX_ADDR_LEN];
  	unsigned long flags;
  
  	LCS_DBF_TEXT(4, trace, "setmclst");
  	for (im4 = in4_dev->mc_list; im4; im4 = im4->next) {
  		lcs_get_mac_for_ipm(im4->multiaddr, buf, card->dev);
  		ipm = lcs_check_addr_entry(card, im4, buf);
  		if (ipm != NULL)
  			continue;	/* Address already in list. */
  		ipm = kzalloc(sizeof(struct lcs_ipm_list), GFP_ATOMIC);
  		if (ipm == NULL) {
  			pr_info("Not enough memory to add"
  				" new multicast entry!\n");
  			break;
  		}
  		memcpy(&ipm->ipm.mac_addr, buf, LCS_MAC_LENGTH);
  		ipm->ipm.ip_addr = im4->multiaddr;
  		ipm->ipm_state = LCS_IPM_STATE_SET_REQUIRED;
  		spin_lock_irqsave(&card->ipm_lock, flags);
  		LCS_DBF_HEX(2,trace,&ipm->ipm.ip_addr,4);
  		list_add(&ipm->list, &card->ipm_list);
  		spin_unlock_irqrestore(&card->ipm_lock, flags);
  	}
  }
  
  static int
  lcs_register_mc_addresses(void *data)
  {
  	struct lcs_card *card;
  	struct in_device *in4_dev;
  
  	card = (struct lcs_card *) data;
  
  	if (!lcs_do_run_thread(card, LCS_SET_MC_THREAD))
  		return 0;
  	LCS_DBF_TEXT(4, trace, "regmulti");
  
  	in4_dev = in_dev_get(card->dev);
  	if (in4_dev == NULL)
  		goto out;
  	read_lock(&in4_dev->mc_list_lock);
  	lcs_remove_mc_addresses(card,in4_dev);
  	lcs_set_mc_addresses(card, in4_dev);
  	read_unlock(&in4_dev->mc_list_lock);
  	in_dev_put(in4_dev);
  
  	netif_carrier_off(card->dev);
  	netif_tx_disable(card->dev);
  	wait_event(card->write.wait_q,
  			(card->write.state != LCS_CH_STATE_RUNNING));
  	lcs_fix_multicast_list(card);
  	if (card->state == DEV_STATE_UP) {
  		netif_carrier_on(card->dev);
  		netif_wake_queue(card->dev);
  	}
  out:
  	lcs_clear_thread_running_bit(card, LCS_SET_MC_THREAD);
  	return 0;
  }
  #endif /* CONFIG_IP_MULTICAST */
  
  /**
   * function called by net device to
   * handle multicast address relevant things
   */
  static void
  lcs_set_multicast_list(struct net_device *dev)
  {
  #ifdef CONFIG_IP_MULTICAST
          struct lcs_card *card;
  
          LCS_DBF_TEXT(4, trace, "setmulti");
          card = (struct lcs_card *) dev->ml_priv;
  
          if (!lcs_set_thread_start_bit(card, LCS_SET_MC_THREAD))
  		schedule_work(&card->kernel_thread_starter);
  #endif /* CONFIG_IP_MULTICAST */
  }
  
  static long
  lcs_check_irb_error(struct ccw_device *cdev, struct irb *irb)
  {
  	if (!IS_ERR(irb))
  		return 0;
  
  	switch (PTR_ERR(irb)) {
  	case -EIO:
  		dev_warn(&cdev->dev,
  			"An I/O-error occurred on the LCS device\n");
  		LCS_DBF_TEXT(2, trace, "ckirberr");
  		LCS_DBF_TEXT_(2, trace, "  rc%d", -EIO);
  		break;
  	case -ETIMEDOUT:
  		dev_warn(&cdev->dev,
  			"A command timed out on the LCS device\n");
  		LCS_DBF_TEXT(2, trace, "ckirberr");
  		LCS_DBF_TEXT_(2, trace, "  rc%d", -ETIMEDOUT);
  		break;
  	default:
  		dev_warn(&cdev->dev,
  			"An error occurred on the LCS device, rc=%ld\n",
  			PTR_ERR(irb));
  		LCS_DBF_TEXT(2, trace, "ckirberr");
  		LCS_DBF_TEXT(2, trace, "  rc???");
  	}
  	return PTR_ERR(irb);
  }
  
  static int
  lcs_get_problem(struct ccw_device *cdev, struct irb *irb)
  {
  	int dstat, cstat;
  	char *sense;
  
  	sense = (char *) irb->ecw;
  	cstat = irb->scsw.cmd.cstat;
  	dstat = irb->scsw.cmd.dstat;
  
  	if (cstat & (SCHN_STAT_CHN_CTRL_CHK | SCHN_STAT_INTF_CTRL_CHK |
  		     SCHN_STAT_CHN_DATA_CHK | SCHN_STAT_CHAIN_CHECK |
  		     SCHN_STAT_PROT_CHECK   | SCHN_STAT_PROG_CHECK)) {
  		LCS_DBF_TEXT(2, trace, "CGENCHK");
  		return 1;
  	}
  	if (dstat & DEV_STAT_UNIT_CHECK) {
  		if (sense[LCS_SENSE_BYTE_1] &
  		    LCS_SENSE_RESETTING_EVENT) {
  			LCS_DBF_TEXT(2, trace, "REVIND");
  			return 1;
  		}
  		if (sense[LCS_SENSE_BYTE_0] &
  		    LCS_SENSE_CMD_REJECT) {
  			LCS_DBF_TEXT(2, trace, "CMDREJ");
  			return 0;
  		}
  		if ((!sense[LCS_SENSE_BYTE_0]) &&
  		    (!sense[LCS_SENSE_BYTE_1]) &&
  		    (!sense[LCS_SENSE_BYTE_2]) &&
  		    (!sense[LCS_SENSE_BYTE_3])) {
  			LCS_DBF_TEXT(2, trace, "ZEROSEN");
  			return 0;
  		}
  		LCS_DBF_TEXT(2, trace, "DGENCHK");
  		return 1;
  	}
  	return 0;
  }
  
  static void
  lcs_schedule_recovery(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(2, trace, "startrec");
  	if (!lcs_set_thread_start_bit(card, LCS_RECOVERY_THREAD))
  		schedule_work(&card->kernel_thread_starter);
  }
  
  /**
   * IRQ Handler for LCS channels
   */
  static void
  lcs_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
  {
  	struct lcs_card *card;
  	struct lcs_channel *channel;
  	int rc, index;
  	int cstat, dstat;
  
  	if (lcs_check_irb_error(cdev, irb))
  		return;
  
  	card = CARD_FROM_DEV(cdev);
  	if (card->read.ccwdev == cdev)
  		channel = &card->read;
  	else
  		channel = &card->write;
  
  	cstat = irb->scsw.cmd.cstat;
  	dstat = irb->scsw.cmd.dstat;
  	LCS_DBF_TEXT_(5, trace, "Rint%s", dev_name(&cdev->dev));
  	LCS_DBF_TEXT_(5, trace, "%4x%4x", irb->scsw.cmd.cstat,
  		      irb->scsw.cmd.dstat);
  	LCS_DBF_TEXT_(5, trace, "%4x%4x", irb->scsw.cmd.fctl,
  		      irb->scsw.cmd.actl);
  
  	/* Check for channel and device errors presented */
  	rc = lcs_get_problem(cdev, irb);
  	if (rc || (dstat & DEV_STAT_UNIT_EXCEP)) {
  		dev_warn(&cdev->dev,
  			"The LCS device stopped because of an error,"
  			" dstat=0x%X, cstat=0x%X \n",
  			    dstat, cstat);
  		if (rc) {
  			channel->state = LCS_CH_STATE_ERROR;
  		}
  	}
  	if (channel->state == LCS_CH_STATE_ERROR) {
  		lcs_schedule_recovery(card);
  		wake_up(&card->wait_q);
  		return;
  	}
  	/* How far in the ccw chain have we processed? */
  	if ((channel->state != LCS_CH_STATE_INIT) &&
  	    (irb->scsw.cmd.fctl & SCSW_FCTL_START_FUNC) &&
  	    (irb->scsw.cmd.cpa != 0)) {
  		index = (struct ccw1 *) __va((addr_t) irb->scsw.cmd.cpa)
  			- channel->ccws;
  		if ((irb->scsw.cmd.actl & SCSW_ACTL_SUSPENDED) ||
  		    (irb->scsw.cmd.cstat & SCHN_STAT_PCI))
  			/* Bloody io subsystem tells us lies about cpa... */
  			index = (index - 1) & (LCS_NUM_BUFFS - 1);
  		while (channel->io_idx != index) {
  			__lcs_processed_buffer(channel,
  					       channel->iob + channel->io_idx);
  			channel->io_idx =
  				(channel->io_idx + 1) & (LCS_NUM_BUFFS - 1);
  		}
  	}
  
  	if ((irb->scsw.cmd.dstat & DEV_STAT_DEV_END) ||
  	    (irb->scsw.cmd.dstat & DEV_STAT_CHN_END) ||
  	    (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK))
  		/* Mark channel as stopped. */
  		channel->state = LCS_CH_STATE_STOPPED;
  	else if (irb->scsw.cmd.actl & SCSW_ACTL_SUSPENDED)
  		/* CCW execution stopped on a suspend bit. */
  		channel->state = LCS_CH_STATE_SUSPENDED;
  	if (irb->scsw.cmd.fctl & SCSW_FCTL_HALT_FUNC) {
  		if (irb->scsw.cmd.cc != 0) {
  			ccw_device_halt(channel->ccwdev, (addr_t) channel);
  			return;
  		}
  		/* The channel has been stopped by halt_IO. */
  		channel->state = LCS_CH_STATE_HALTED;
  	}
  	if (irb->scsw.cmd.fctl & SCSW_FCTL_CLEAR_FUNC)
  		channel->state = LCS_CH_STATE_CLEARED;
  	/* Do the rest in the tasklet. */
  	tasklet_schedule(&channel->irq_tasklet);
  }
  
  /**
   * Tasklet for IRQ handler
   */
  static void
  lcs_tasklet(unsigned long data)
  {
  	unsigned long flags;
  	struct lcs_channel *channel;
  	struct lcs_buffer *iob;
  	int buf_idx;
  	int rc;
  
  	channel = (struct lcs_channel *) data;
  	LCS_DBF_TEXT_(5, trace, "tlet%s", dev_name(&channel->ccwdev->dev));
  
  	/* Check for processed buffers. */
  	iob = channel->iob;
  	buf_idx = channel->buf_idx;
  	while (iob[buf_idx].state == LCS_BUF_STATE_PROCESSED) {
  		/* Do the callback thing. */
  		if (iob[buf_idx].callback != NULL)
  			iob[buf_idx].callback(channel, iob + buf_idx);
  		buf_idx = (buf_idx + 1) & (LCS_NUM_BUFFS - 1);
  	}
  	channel->buf_idx = buf_idx;
  
  	if (channel->state == LCS_CH_STATE_STOPPED)
  		// FIXME: what if rc != 0 ??
  		rc = lcs_start_channel(channel);
  	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
  	if (channel->state == LCS_CH_STATE_SUSPENDED &&
  	    channel->iob[channel->io_idx].state == LCS_BUF_STATE_READY) {
  		// FIXME: what if rc != 0 ??
  		rc = __lcs_resume_channel(channel);
  	}
  	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
  
  	/* Something happened on the channel. Wake up waiters. */
  	wake_up(&channel->wait_q);
  }
  
  /**
   * Finish current tx buffer and make it ready for transmit.
   */
  static void
  __lcs_emit_txbuffer(struct lcs_card *card)
  {
  	LCS_DBF_TEXT(5, trace, "emittx");
  	*(__u16 *)(card->tx_buffer->data + card->tx_buffer->count) = 0;
  	card->tx_buffer->count += 2;
  	lcs_ready_buffer(&card->write, card->tx_buffer);
  	card->tx_buffer = NULL;
  	card->tx_emitted++;
  }
  
  /**
   * Callback for finished tx buffers.
   */
  static void
  lcs_txbuffer_cb(struct lcs_channel *channel, struct lcs_buffer *buffer)
  {
  	struct lcs_card *card;
  
  	LCS_DBF_TEXT(5, trace, "txbuffcb");
  	/* Put buffer back to pool. */
  	lcs_release_buffer(channel, buffer);
  	card = container_of(channel, struct lcs_card, write);
  	if (netif_queue_stopped(card->dev) && netif_carrier_ok(card->dev))
  		netif_wake_queue(card->dev);
  	spin_lock(&card->lock);
  	card->tx_emitted--;
  	if (card->tx_emitted <= 0 && card->tx_buffer != NULL)
  		/*
  		 * Last running tx buffer has finished. Submit partially
  		 * filled current buffer.
  		 */
  		__lcs_emit_txbuffer(card);
  	spin_unlock(&card->lock);
  }
  
  /**
   * Packet transmit function called by network stack
   */
  static int
  __lcs_start_xmit(struct lcs_card *card, struct sk_buff *skb,
  		 struct net_device *dev)
  {
  	struct lcs_header *header;
  	int rc = NETDEV_TX_OK;
  
  	LCS_DBF_TEXT(5, trace, "hardxmit");
  	if (skb == NULL) {
  		card->stats.tx_dropped++;
  		card->stats.tx_errors++;
  		return NETDEV_TX_OK;
  	}
  	if (card->state != DEV_STATE_UP) {
  		dev_kfree_skb(skb);
  		card->stats.tx_dropped++;
  		card->stats.tx_errors++;
  		card->stats.tx_carrier_errors++;
  		return NETDEV_TX_OK;
  	}
  	if (skb->protocol == htons(ETH_P_IPV6)) {
  		dev_kfree_skb(skb);
  		return NETDEV_TX_OK;
  	}
  	netif_stop_queue(card->dev);
  	spin_lock(&card->lock);
  	if (card->tx_buffer != NULL &&
  	    card->tx_buffer->count + sizeof(struct lcs_header) +
  	    skb->len + sizeof(u16) > LCS_IOBUFFERSIZE)
  		/* skb too big for current tx buffer. */
  		__lcs_emit_txbuffer(card);
  	if (card->tx_buffer == NULL) {
  		/* Get new tx buffer */
  		card->tx_buffer = lcs_get_buffer(&card->write);
  		if (card->tx_buffer == NULL) {
  			card->stats.tx_dropped++;
  			rc = NETDEV_TX_BUSY;
  			goto out;
  		}
  		card->tx_buffer->callback = lcs_txbuffer_cb;
  		card->tx_buffer->count = 0;
  	}
  	header = (struct lcs_header *)
  		(card->tx_buffer->data + card->tx_buffer->count);
  	card->tx_buffer->count += skb->len + sizeof(struct lcs_header);
  	header->offset = card->tx_buffer->count;
  	header->type = card->lan_type;
  	header->slot = card->portno;
  	skb_copy_from_linear_data(skb, header + 1, skb->len);
  	spin_unlock(&card->lock);
  	card->stats.tx_bytes += skb->len;
  	card->stats.tx_packets++;
  	dev_kfree_skb(skb);
  	netif_wake_queue(card->dev);
  	spin_lock(&card->lock);
  	if (card->tx_emitted <= 0 && card->tx_buffer != NULL)
  		/* If this is the first tx buffer emit it immediately. */
  		__lcs_emit_txbuffer(card);
  out:
  	spin_unlock(&card->lock);
  	return rc;
  }
  
  static int
  lcs_start_xmit(struct sk_buff *skb, struct net_device *dev)
  {
  	struct lcs_card *card;
  	int rc;
  
  	LCS_DBF_TEXT(5, trace, "pktxmit");
  	card = (struct lcs_card *) dev->ml_priv;
  	rc = __lcs_start_xmit(card, skb, dev);
  	return rc;
  }
  
  /**
   * send startlan and lanstat command to make LCS device ready
   */
  static int
  lcs_startlan_auto(struct lcs_card *card)
  {
  	int rc;
  
  	LCS_DBF_TEXT(2, trace, "strtauto");
  #ifdef CONFIG_NET_ETHERNET
  	card->lan_type = LCS_FRAME_TYPE_ENET;
  	rc = lcs_send_startlan(card, LCS_INITIATOR_TCPIP);
  	if (rc == 0)
  		return 0;
  
  #endif
  #ifdef CONFIG_TR
  	card->lan_type = LCS_FRAME_TYPE_TR;
  	rc = lcs_send_startlan(card, LCS_INITIATOR_TCPIP);
  	if (rc == 0)
  		return 0;
  #endif
  #ifdef CONFIG_FDDI
  	card->lan_type = LCS_FRAME_TYPE_FDDI;
  	rc = lcs_send_startlan(card, LCS_INITIATOR_TCPIP);
  	if (rc == 0)
  		return 0;
  #endif
  	return -EIO;
  }
  
  static int
  lcs_startlan(struct lcs_card *card)
  {
  	int rc, i;
  
  	LCS_DBF_TEXT(2, trace, "startlan");
  	rc = 0;
  	if (card->portno != LCS_INVALID_PORT_NO) {
  		if (card->lan_type == LCS_FRAME_TYPE_AUTO)
  			rc = lcs_startlan_auto(card);
  		else
  			rc = lcs_send_startlan(card, LCS_INITIATOR_TCPIP);
  	} else {
                  for (i = 0; i <= 16; i++) {
                          card->portno = i;
                          if (card->lan_type != LCS_FRAME_TYPE_AUTO)
                                  rc = lcs_send_startlan(card,
                                                         LCS_INITIATOR_TCPIP);
                          else
                                  /* autodetecting lan type */
                                  rc = lcs_startlan_auto(card);
                          if (rc == 0)
                                  break;
                  }
          }
  	if (rc == 0)
  		return lcs_send_lanstat(card);
  	return rc;
  }
  
  /**
   * LCS detect function
   * setup channels and make them I/O ready
   */
  static int
  lcs_detect(struct lcs_card *card)
  {
  	int rc = 0;
  
  	LCS_DBF_TEXT(2, setup, "lcsdetct");
  	/* start/reset card */
  	if (card->dev)
  		netif_stop_queue(card->dev);
  	rc = lcs_stop_channels(card);
  	if (rc == 0) {
  		rc = lcs_start_channels(card);
  		if (rc == 0) {
  			rc = lcs_send_startup(card, LCS_INITIATOR_TCPIP);
  			if (rc == 0)
  				rc = lcs_startlan(card);
  		}
  	}
  	if (rc == 0) {
  		card->state = DEV_STATE_UP;
  	} else {
  		card->state = DEV_STATE_DOWN;
  		card->write.state = LCS_CH_STATE_INIT;
  		card->read.state =  LCS_CH_STATE_INIT;
  	}
  	return rc;
  }
  
  /**
   * LCS Stop card
   */
  static int
  lcs_stopcard(struct lcs_card *card)
  {
  	int rc;
  
  	LCS_DBF_TEXT(3, setup, "stopcard");
  
  	if (card->read.state != LCS_CH_STATE_STOPPED &&
  	    card->write.state != LCS_CH_STATE_STOPPED &&
  	    card->read.state != LCS_CH_STATE_ERROR &&
  	    card->write.state != LCS_CH_STATE_ERROR &&
  	    card->state == DEV_STATE_UP) {
  		lcs_clear_multicast_list(card);
  		rc = lcs_send_stoplan(card,LCS_INITIATOR_TCPIP);
  		rc = lcs_send_shutdown(card);
  	}
  	rc = lcs_stop_channels(card);
  	card->state = DEV_STATE_DOWN;
  
  	return rc;
  }
  
  /**
   * Kernel Thread helper functions for LGW initiated commands
   */
  static void
  lcs_start_kernel_thread(struct work_struct *work)
  {
  	struct lcs_card *card = container_of(work, struct lcs_card, kernel_thread_starter);
  	LCS_DBF_TEXT(5, trace, "krnthrd");
  	if (lcs_do_start_thread(card, LCS_RECOVERY_THREAD))
  		kthread_run(lcs_recovery, card, "lcs_recover");
  #ifdef CONFIG_IP_MULTICAST
  	if (lcs_do_start_thread(card, LCS_SET_MC_THREAD))
  		kthread_run(lcs_register_mc_addresses, card, "regipm");
  #endif
  }
  
  /**
   * Process control frames.
   */
  static void
  lcs_get_control(struct lcs_card *card, struct lcs_cmd *cmd)
  {
  	LCS_DBF_TEXT(5, trace, "getctrl");
  	if (cmd->initiator == LCS_INITIATOR_LGW) {
  		switch(cmd->cmd_code) {
  		case LCS_CMD_STARTUP:
  		case LCS_CMD_STARTLAN:
  			lcs_schedule_recovery(card);
  			break;
  		case LCS_CMD_STOPLAN:
  			pr_warning("Stoplan for %s initiated by LGW.\n",
  				   card->dev->name);
  			if (card->dev)
  				netif_carrier_off(card->dev);
  			break;
  		default:
  			LCS_DBF_TEXT(5, trace, "noLGWcmd");
  			break;
  		}
  	} else
  		lcs_notify_lancmd_waiters(card, cmd);
  }
  
  /**
   * Unpack network packet.
   */
  static void
  lcs_get_skb(struct lcs_card *card, char *skb_data, unsigned int skb_len)
  {
  	struct sk_buff *skb;
  
  	LCS_DBF_TEXT(5, trace, "getskb");
  	if (card->dev == NULL ||
  	    card->state != DEV_STATE_UP)
  		/* The card isn't up. Ignore the packet. */
  		return;
  
  	skb = dev_alloc_skb(skb_len);
  	if (skb == NULL) {
  		dev_err(&card->dev->dev,
  			" Allocating a socket buffer to interface %s failed\n",
  			  card->dev->name);
  		card->stats.rx_dropped++;
  		return;
  	}
  	memcpy(skb_put(skb, skb_len), skb_data, skb_len);
  	skb->protocol =	card->lan_type_trans(skb, card->dev);
  	card->stats.rx_bytes += skb_len;
  	card->stats.rx_packets++;
  	if (skb->protocol == htons(ETH_P_802_2))
  		*((__u32 *)skb->cb) = ++card->pkt_seq;
  	netif_rx(skb);
  }
  
  /**
   * LCS main routine to get packets and lancmd replies from the buffers
   */
  static void
  lcs_get_frames_cb(struct lcs_channel *channel, struct lcs_buffer *buffer)
  {
  	struct lcs_card *card;
  	struct lcs_header *lcs_hdr;
  	__u16 offset;
  
  	LCS_DBF_TEXT(5, trace, "lcsgtpkt");
  	lcs_hdr = (struct lcs_header *) buffer->data;
  	if (lcs_hdr->offset == LCS_ILLEGAL_OFFSET) {
  		LCS_DBF_TEXT(4, trace, "-eiogpkt");
  		return;
  	}
  	card = container_of(channel, struct lcs_card, read);
  	offset = 0;
  	while (lcs_hdr->offset != 0) {
  		if (lcs_hdr->offset <= 0 ||
  		    lcs_hdr->offset > LCS_IOBUFFERSIZE ||
  		    lcs_hdr->offset < offset) {
  			/* Offset invalid. */
  			card->stats.rx_length_errors++;
  			card->stats.rx_errors++;
  			return;
  		}
  		/* What kind of frame is it? */
  		if (lcs_hdr->type == LCS_FRAME_TYPE_CONTROL)
  			/* Control frame. */
  			lcs_get_control(card, (struct lcs_cmd *) lcs_hdr);
  		else if (lcs_hdr->type == LCS_FRAME_TYPE_ENET ||
  			 lcs_hdr->type == LCS_FRAME_TYPE_TR ||
  			 lcs_hdr->type == LCS_FRAME_TYPE_FDDI)
  			/* Normal network packet. */
  			lcs_get_skb(card, (char *)(lcs_hdr + 1),
  				    lcs_hdr->offset - offset -
  				    sizeof(struct lcs_header));
  		else
  			/* Unknown frame type. */
  			; // FIXME: error message ?
  		/* Proceed to next frame. */
  		offset = lcs_hdr->offset;
  		lcs_hdr->offset = LCS_ILLEGAL_OFFSET;
  		lcs_hdr = (struct lcs_header *) (buffer->data + offset);
  	}
  	/* The buffer is now empty. Make it ready again. */
  	lcs_ready_buffer(&card->read, buffer);
  }
  
  /**
   * get network statistics for ifconfig and other user programs
   */
  static struct net_device_stats *
  lcs_getstats(struct net_device *dev)
  {
  	struct lcs_card *card;
  
  	LCS_DBF_TEXT(4, trace, "netstats");
  	card = (struct lcs_card *) dev->ml_priv;
  	return &card->stats;
  }
  
  /**
   * stop lcs device
   * This function will be called by user doing ifconfig xxx down
   */
  static int
  lcs_stop_device(struct net_device *dev)
  {
  	struct lcs_card *card;
  	int rc;
  
  	LCS_DBF_TEXT(2, trace, "stopdev");
  	card   = (struct lcs_card *) dev->ml_priv;
  	netif_carrier_off(dev);
  	netif_tx_disable(dev);
  	dev->flags &= ~IFF_UP;
  	wait_event(card->write.wait_q,
  		(card->write.state != LCS_CH_STATE_RUNNING));
  	rc = lcs_stopcard(card);
  	if (rc)
  		dev_err(&card->dev->dev,
  			" Shutting down the LCS device failed\n ");
  	return rc;
  }
  
  /**
   * start lcs device and make it runnable
   * This function will be called by user doing ifconfig xxx up
   */
  static int
  lcs_open_device(struct net_device *dev)
  {
  	struct lcs_card *card;
  	int rc;
  
  	LCS_DBF_TEXT(2, trace, "opendev");
  	card = (struct lcs_card *) dev->ml_priv;
  	/* initialize statistics */
  	rc = lcs_detect(card);
  	if (rc) {
  		pr_err("Error in opening device!\n");
  
  	} else {
  		dev->flags |= IFF_UP;
  		netif_carrier_on(dev);
  		netif_wake_queue(dev);
  		card->state = DEV_STATE_UP;
  	}
  	return rc;
  }
  
  /**
   * show function for portno called by cat or similar things
   */
  static ssize_t
  lcs_portno_show (struct device *dev, struct device_attribute *attr, char *buf)
  {
          struct lcs_card *card;
  
  	card = dev_get_drvdata(dev);
  
          if (!card)
                  return 0;
  
          return sprintf(buf, "%d\n", card->portno);
  }
  
  /**
   * store the value which is piped to file portno
   */
  static ssize_t
  lcs_portno_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
  {
          struct lcs_card *card;
          int value;
  
  	card = dev_get_drvdata(dev);
  
          if (!card)
                  return 0;
  
          sscanf(buf, "%u", &value);
          /* TODO: sanity checks */
          card->portno = value;
  
          return count;
  
  }
  
  static DEVICE_ATTR(portno, 0644, lcs_portno_show, lcs_portno_store);
  
  const char *lcs_type[] = {
  	"not a channel",
  	"2216 parallel",
  	"2216 channel",
  	"OSA LCS card",
  	"unknown channel type",
  	"unsupported channel type",
  };
  
  static ssize_t
  lcs_type_show(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct ccwgroup_device *cgdev;
  
  	cgdev = to_ccwgroupdev(dev);
  	if (!cgdev)
  		return -ENODEV;
  
  	return sprintf(buf, "%s\n", lcs_type[cgdev->cdev[0]->id.driver_info]);
  }
  
  static DEVICE_ATTR(type, 0444, lcs_type_show, NULL);
  
  static ssize_t
  lcs_timeout_show(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct lcs_card *card;
  
  	card = dev_get_drvdata(dev);
  
  	return card ? sprintf(buf, "%u\n", card->lancmd_timeout) : 0;
  }
  
  static ssize_t
  lcs_timeout_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
  {
          struct lcs_card *card;
          int value;
  
  	card = dev_get_drvdata(dev);
  
          if (!card)
                  return 0;
  
          sscanf(buf, "%u", &value);
          /* TODO: sanity checks */
          card->lancmd_timeout = value;
  
          return count;
  
  }
  
  static DEVICE_ATTR(lancmd_timeout, 0644, lcs_timeout_show, lcs_timeout_store);
  
  static ssize_t
  lcs_dev_recover_store(struct device *dev, struct device_attribute *attr,
  		      const char *buf, size_t count)
  {
  	struct lcs_card *card = dev_get_drvdata(dev);
  	char *tmp;
  	int i;
  
  	if (!card)
  		return -EINVAL;
  	if (card->state != DEV_STATE_UP)
  		return -EPERM;
  	i = simple_strtoul(buf, &tmp, 16);
  	if (i == 1)
  		lcs_schedule_recovery(card);
  	return count;
  }
  
  static DEVICE_ATTR(recover, 0200, NULL, lcs_dev_recover_store);
  
  static struct attribute * lcs_attrs[] = {
  	&dev_attr_portno.attr,
  	&dev_attr_type.attr,
  	&dev_attr_lancmd_timeout.attr,
  	&dev_attr_recover.attr,
  	NULL,
  };
  
  static struct attribute_group lcs_attr_group = {
  	.attrs = lcs_attrs,
  };
  
  /**
   * lcs_probe_device is called on establishing a new ccwgroup_device.
   */
  static int
  lcs_probe_device(struct ccwgroup_device *ccwgdev)
  {
  	struct lcs_card *card;
  	int ret;
  
  	if (!get_device(&ccwgdev->dev))
  		return -ENODEV;
  
  	LCS_DBF_TEXT(2, setup, "add_dev");
          card = lcs_alloc_card();
          if (!card) {
  		LCS_DBF_TEXT_(2, setup, "  rc%d", -ENOMEM);
  		put_device(&ccwgdev->dev);
                  return -ENOMEM;
          }
  	ret = sysfs_create_group(&ccwgdev->dev.kobj, &lcs_attr_group);
  	if (ret) {
  		lcs_free_card(card);
  		put_device(&ccwgdev->dev);
  		return ret;
          }
  	dev_set_drvdata(&ccwgdev->dev, card);
  	ccwgdev->cdev[0]->handler = lcs_irq;
  	ccwgdev->cdev[1]->handler = lcs_irq;
  	card->gdev = ccwgdev;
  	INIT_WORK(&card->kernel_thread_starter, lcs_start_kernel_thread);
  	card->thread_start_mask = 0;
  	card->thread_allowed_mask = 0;
  	card->thread_running_mask = 0;
          return 0;
  }
  
  static int
  lcs_register_netdev(struct ccwgroup_device *ccwgdev)
  {
  	struct lcs_card *card;
  
  	LCS_DBF_TEXT(2, setup, "regnetdv");
  	card = dev_get_drvdata(&ccwgdev->dev);
  	if (card->dev->reg_state != NETREG_UNINITIALIZED)
  		return 0;
  	SET_NETDEV_DEV(card->dev, &ccwgdev->dev);
  	return register_netdev(card->dev);
  }
  
  /**
   * lcs_new_device will be called by setting the group device online.
   */
  static const struct net_device_ops lcs_netdev_ops = {
  	.ndo_open		= lcs_open_device,
  	.ndo_stop		= lcs_stop_device,
  	.ndo_get_stats		= lcs_getstats,
  	.ndo_start_xmit		= lcs_start_xmit,
  };
  
  static const struct net_device_ops lcs_mc_netdev_ops = {
  	.ndo_open		= lcs_open_device,
  	.ndo_stop		= lcs_stop_device,
  	.ndo_get_stats		= lcs_getstats,
  	.ndo_start_xmit		= lcs_start_xmit,
  	.ndo_set_multicast_list = lcs_set_multicast_list,
  };
  
  static int
  lcs_new_device(struct ccwgroup_device *ccwgdev)
  {
  	struct  lcs_card *card;
  	struct net_device *dev=NULL;
  	enum lcs_dev_states recover_state;
  	int rc;
  
  	card = dev_get_drvdata(&ccwgdev->dev);
  	if (!card)
  		return -ENODEV;
  
  	LCS_DBF_TEXT(2, setup, "newdev");
  	LCS_DBF_HEX(3, setup, &card, sizeof(void*));
  	card->read.ccwdev  = ccwgdev->cdev[0];
  	card->write.ccwdev = ccwgdev->cdev[1];
  
  	recover_state = card->state;
  	rc = ccw_device_set_online(card->read.ccwdev);
  	if (rc)
  		goto out_err;
  	rc = ccw_device_set_online(card->write.ccwdev);
  	if (rc)
  		goto out_werr;
  
  	LCS_DBF_TEXT(3, setup, "lcsnewdv");
  
  	lcs_setup_card(card);
  	rc = lcs_detect(card);
  	if (rc) {
  		LCS_DBF_TEXT(2, setup, "dtctfail");
  		dev_err(&card->dev->dev,
  			"Detecting a network adapter for LCS devices"
  			" failed with rc=%d (0x%x)\n", rc, rc);
  		lcs_stopcard(card);
  		goto out;
  	}
  	if (card->dev) {
  		LCS_DBF_TEXT(2, setup, "samedev");
  		LCS_DBF_HEX(3, setup, &card, sizeof(void*));
  		goto netdev_out;
  	}
  	switch (card->lan_type) {
  #ifdef CONFIG_NET_ETHERNET
  	case LCS_FRAME_TYPE_ENET:
  		card->lan_type_trans = eth_type_trans;
  		dev = alloc_etherdev(0);
  		break;
  #endif
  #ifdef CONFIG_TR
  	case LCS_FRAME_TYPE_TR:
  		card->lan_type_trans = tr_type_trans;
  		dev = alloc_trdev(0);
  		break;
  #endif
  #ifdef CONFIG_FDDI
  	case LCS_FRAME_TYPE_FDDI:
  		card->lan_type_trans = fddi_type_trans;
  		dev = alloc_fddidev(0);
  		break;
  #endif
  	default:
  		LCS_DBF_TEXT(3, setup, "errinit");
  		pr_err(" Initialization failed\n");
  		goto out;
  	}
  	if (!dev)
  		goto out;
  	card->dev = dev;
  	card->dev->ml_priv = card;
  	card->dev->netdev_ops = &lcs_netdev_ops;
  	memcpy(card->dev->dev_addr, card->mac, LCS_MAC_LENGTH);
  #ifdef CONFIG_IP_MULTICAST
  	if (!lcs_check_multicast_support(card))
  		card->dev->netdev_ops = &lcs_mc_netdev_ops;
  #endif
  netdev_out:
  	lcs_set_allowed_threads(card,0xffffffff);
  	if (recover_state == DEV_STATE_RECOVER) {
  		lcs_set_multicast_list(card->dev);
  		card->dev->flags |= IFF_UP;
  		netif_carrier_on(card->dev);
  		netif_wake_queue(card->dev);
  		card->state = DEV_STATE_UP;
  	} else {
  		lcs_stopcard(card);
  	}
  
  	if (lcs_register_netdev(ccwgdev) != 0)
  		goto out;
  
  	/* Print out supported assists: IPv6 */
  	pr_info("LCS device %s %s IPv6 support\n", card->dev->name,
  		(card->ip_assists_supported & LCS_IPASS_IPV6_SUPPORT) ?
  		"with" : "without");
  	/* Print out supported assist: Multicast */
  	pr_info("LCS device %s %s Multicast support\n", card->dev->name,
  		(card->ip_assists_supported & LCS_IPASS_MULTICAST_SUPPORT) ?
  		"with" : "without");
  	return 0;
  out:
  
  	ccw_device_set_offline(card->write.ccwdev);
  out_werr:
  	ccw_device_set_offline(card->read.ccwdev);
  out_err:
  	return -ENODEV;
  }
  
  /**
   * lcs_shutdown_device, called when setting the group device offline.
   */
  static int
  __lcs_shutdown_device(struct ccwgroup_device *ccwgdev, int recovery_mode)
  {
  	struct lcs_card *card;
  	enum lcs_dev_states recover_state;
  	int ret;
  
  	LCS_DBF_TEXT(3, setup, "shtdndev");
  	card = dev_get_drvdata(&ccwgdev->dev);
  	if (!card)
  		return -ENODEV;
  	if (recovery_mode == 0) {
  		lcs_set_allowed_threads(card, 0);
  		if (lcs_wait_for_threads(card, LCS_SET_MC_THREAD))
  			return -ERESTARTSYS;
  	}
  	LCS_DBF_HEX(3, setup, &card, sizeof(void*));
  	recover_state = card->state;
  
  	ret = lcs_stop_device(card->dev);
  	ret = ccw_device_set_offline(card->read.ccwdev);
  	ret = ccw_device_set_offline(card->write.ccwdev);
  	if (recover_state == DEV_STATE_UP) {
  		card->state = DEV_STATE_RECOVER;
  	}
  	if (ret)
  		return ret;
  	return 0;
  }
  
  static int
  lcs_shutdown_device(struct ccwgroup_device *ccwgdev)
  {
  	return __lcs_shutdown_device(ccwgdev, 0);
  }
  
  /**
   * drive lcs recovery after startup and startlan initiated by Lan Gateway
   */
  static int
  lcs_recovery(void *ptr)
  {
  	struct lcs_card *card;
  	struct ccwgroup_device *gdev;
          int rc;
  
  	card = (struct lcs_card *) ptr;
  
  	LCS_DBF_TEXT(4, trace, "recover1");
  	if (!lcs_do_run_thread(card, LCS_RECOVERY_THREAD))
  		return 0;
  	LCS_DBF_TEXT(4, trace, "recover2");
  	gdev = card->gdev;
  	dev_warn(&gdev->dev,
  		"A recovery process has been started for the LCS device\n");
  	rc = __lcs_shutdown_device(gdev, 1);
  	rc = lcs_new_device(gdev);
  	if (!rc)
  		pr_info("Device %s successfully recovered!\n",
  			card->dev->name);
  	else
  		pr_info("Device %s could not be recovered!\n",
  			card->dev->name);
  	lcs_clear_thread_running_bit(card, LCS_RECOVERY_THREAD);
  	return 0;
  }
  
  /**
   * lcs_remove_device, free buffers and card
   */
  static void
  lcs_remove_device(struct ccwgroup_device *ccwgdev)
  {
  	struct lcs_card *card;
  
  	card = dev_get_drvdata(&ccwgdev->dev);
  	if (!card)
  		return;
  
  	LCS_DBF_TEXT(3, setup, "remdev");
  	LCS_DBF_HEX(3, setup, &card, sizeof(void*));
  	if (ccwgdev->state == CCWGROUP_ONLINE) {
  		lcs_shutdown_device(ccwgdev);
  	}
  	if (card->dev)
  		unregister_netdev(card->dev);
  	sysfs_remove_group(&ccwgdev->dev.kobj, &lcs_attr_group);
  	lcs_cleanup_card(card);
  	lcs_free_card(card);
  	put_device(&ccwgdev->dev);
  }
  
  static int lcs_pm_suspend(struct lcs_card *card)
  {
  	if (card->dev)
  		netif_device_detach(card->dev);
  	lcs_set_allowed_threads(card, 0);
  	lcs_wait_for_threads(card, 0xffffffff);
  	if (card->state != DEV_STATE_DOWN)
  		__lcs_shutdown_device(card->gdev, 1);
  	return 0;
  }
  
  static int lcs_pm_resume(struct lcs_card *card)
  {
  	int rc = 0;
  
  	if (card->state == DEV_STATE_RECOVER)
  		rc = lcs_new_device(card->gdev);
  	if (card->dev)
  		netif_device_attach(card->dev);
  	if (rc) {
  		dev_warn(&card->gdev->dev, "The lcs device driver "
  			"failed to recover the device\n");
  	}
  	return rc;
  }
  
  static int lcs_prepare(struct ccwgroup_device *gdev)
  {
  	return 0;
  }
  
  static void lcs_complete(struct ccwgroup_device *gdev)
  {
  	return;
  }
  
  static int lcs_freeze(struct ccwgroup_device *gdev)
  {
  	struct lcs_card *card = dev_get_drvdata(&gdev->dev);
  	return lcs_pm_suspend(card);
  }
  
  static int lcs_thaw(struct ccwgroup_device *gdev)
  {
  	struct lcs_card *card = dev_get_drvdata(&gdev->dev);
  	return lcs_pm_resume(card);
  }
  
  static int lcs_restore(struct ccwgroup_device *gdev)
  {
  	struct lcs_card *card = dev_get_drvdata(&gdev->dev);
  	return lcs_pm_resume(card);
  }
  
  static struct ccw_device_id lcs_ids[] = {
  	{CCW_DEVICE(0x3088, 0x08), .driver_info = lcs_channel_type_parallel},
  	{CCW_DEVICE(0x3088, 0x1f), .driver_info = lcs_channel_type_2216},
  	{CCW_DEVICE(0x3088, 0x60), .driver_info = lcs_channel_type_osa2},
  	{},
  };
  MODULE_DEVICE_TABLE(ccw, lcs_ids);
  
  static struct ccw_driver lcs_ccw_driver = {
  	.owner	= THIS_MODULE,
  	.name	= "lcs",
  	.ids	= lcs_ids,
  	.probe	= ccwgroup_probe_ccwdev,
  	.remove	= ccwgroup_remove_ccwdev,
  };
  
  /**
   * LCS ccwgroup driver registration
   */
  static struct ccwgroup_driver lcs_group_driver = {
  	.owner       = THIS_MODULE,
  	.name        = "lcs",
  	.max_slaves  = 2,
  	.driver_id   = 0xD3C3E2,
  	.probe       = lcs_probe_device,
  	.remove      = lcs_remove_device,
  	.set_online  = lcs_new_device,
  	.set_offline = lcs_shutdown_device,
  	.prepare     = lcs_prepare,
  	.complete    = lcs_complete,
  	.freeze	     = lcs_freeze,
  	.thaw	     = lcs_thaw,
  	.restore     = lcs_restore,
  };
  
  static ssize_t
  lcs_driver_group_store(struct device_driver *ddrv, const char *buf,
  		       size_t count)
  {
  	int err;
  	err = ccwgroup_create_from_string(lcs_root_dev,
  					  lcs_group_driver.driver_id,
  					  &lcs_ccw_driver, 2, buf);
  	return err ? err : count;
  }
  
  static DRIVER_ATTR(group, 0200, NULL, lcs_driver_group_store);
  
  static struct attribute *lcs_group_attrs[] = {
  	&driver_attr_group.attr,
  	NULL,
  };
  
  static struct attribute_group lcs_group_attr_group = {
  	.attrs = lcs_group_attrs,
  };
  
  static const struct attribute_group *lcs_group_attr_groups[] = {
  	&lcs_group_attr_group,
  	NULL,
  };
  
  /**
   *  LCS Module/Kernel initialization function
   */
  static int
  __init lcs_init_module(void)
  {
  	int rc;
  
  	pr_info("Loading %s\n", version);
  	rc = lcs_register_debug_facility();
  	LCS_DBF_TEXT(0, setup, "lcsinit");
  	if (rc)
  		goto out_err;
  	lcs_root_dev = root_device_register("lcs");
  	rc = IS_ERR(lcs_root_dev) ? PTR_ERR(lcs_root_dev) : 0;
  	if (rc)
  		goto register_err;
  	rc = ccw_driver_register(&lcs_ccw_driver);
  	if (rc)
  		goto ccw_err;
  	lcs_group_driver.driver.groups = lcs_group_attr_groups;
  	rc = ccwgroup_driver_register(&lcs_group_driver);
  	if (rc)
  		goto ccwgroup_err;
  	return 0;
  
  ccwgroup_err:
  	ccw_driver_unregister(&lcs_ccw_driver);
  ccw_err:
  	root_device_unregister(lcs_root_dev);
  register_err:
  	lcs_unregister_debug_facility();
  out_err:
  	pr_err("Initializing the lcs device driver failed\n");
  	return rc;
  }
  
  
  /**
   *  LCS module cleanup function
   */
  static void
  __exit lcs_cleanup_module(void)
  {
  	pr_info("Terminating lcs module.\n");
  	LCS_DBF_TEXT(0, trace, "cleanup");
  	driver_remove_file(&lcs_group_driver.driver,
  			   &driver_attr_group);
  	ccwgroup_driver_unregister(&lcs_group_driver);
  	ccw_driver_unregister(&lcs_ccw_driver);
  	root_device_unregister(lcs_root_dev);
  	lcs_unregister_debug_facility();
  }
  
  module_init(lcs_init_module);
  module_exit(lcs_cleanup_module);
  
  MODULE_AUTHOR("Frank Pavlic <fpavlic@de.ibm.com>");
  MODULE_LICENSE("GPL");
  
  