lcs: replace PTR_RET with PTR_ERR_OR_ZERO

[deliverable/linux.git] / drivers / s390 / net / lcs.c

/*
 *  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/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_ETHERNET) && !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 command.
 */
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);
        destroy_timer_on_stack(&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 no one 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");
        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 = rcu_dereference(in4_dev->mc_list);
                     im4 != NULL; im4 = rcu_dereference(im4->next_rcu)) {
                        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 = rcu_dereference(in4_dev->mc_list); im4 != NULL;
             im4 = rcu_dereference(im4->next_rcu)) {
                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;
        rcu_read_lock();
        lcs_remove_mc_addresses(card,in4_dev);
        lcs_set_mc_addresses(card, in4_dev);
        rcu_read_unlock();
        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;

        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)
                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)
                __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_ETHERNET
        card->lan_type = LCS_FRAME_TYPE_ENET;
        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);

static 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,
};
static const struct attribute_group *lcs_attr_groups[] = {
        &lcs_attr_group,
        NULL,
};
static const struct device_type lcs_devtype = {
        .name = "lcs",
        .groups = lcs_attr_groups,
};

/**
 * lcs_probe_device is called on establishing a new ccwgroup_device.
 */
static int
lcs_probe_device(struct ccwgroup_device *ccwgdev)
{
        struct lcs_card *card;

        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;
        }
        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;
        ccwgdev->dev.type = &lcs_devtype;

        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_rx_mode        = 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_ETHERNET
        case LCS_FRAME_TYPE_ENET:
                card->lan_type_trans = eth_type_trans;
                dev = alloc_etherdev(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 = 0, ret2 = 0, ret3 = 0;

        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);
        ret2 = ccw_device_set_offline(card->read.ccwdev);
        ret3 = ccw_device_set_offline(card->write.ccwdev);
        if (!ret)
                ret = (ret2) ? ret2 : ret3;
        if (ret)
                LCS_DBF_TEXT_(3, setup, "1err:%d", ret);
        if (recover_state == DEV_STATE_UP) {
                card->state = DEV_STATE_RECOVER;
        }
        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);
        lcs_cleanup_card(card);
        lcs_free_card(card);
        dev_set_drvdata(&ccwgdev->dev, NULL);
        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 = {
        .driver = {
                .owner  = THIS_MODULE,
                .name   = "lcs",
        },
        .ids    = lcs_ids,
        .probe  = ccwgroup_probe_ccwdev,
        .remove = ccwgroup_remove_ccwdev,
        .int_class = IRQIO_LCS,
};

/**
 * LCS ccwgroup driver registration
 */
static struct ccwgroup_driver lcs_group_driver = {
        .driver = {
                .owner  = THIS_MODULE,
                .name   = "lcs",
        },
        .setup       = 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_dev(lcs_root_dev, &lcs_group_driver, 2, buf);
        return err ? err : count;
}
static DRIVER_ATTR(group, 0200, NULL, lcs_driver_group_store);

static struct attribute *lcs_drv_attrs[] = {
        &driver_attr_group.attr,
        NULL,
};
static struct attribute_group lcs_drv_attr_group = {
        .attrs = lcs_drv_attrs,
};
static const struct attribute_group *lcs_drv_attr_groups[] = {
        &lcs_drv_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 = PTR_ERR_OR_ZERO(lcs_root_dev);
        if (rc)
                goto register_err;
        rc = ccw_driver_register(&lcs_ccw_driver);
        if (rc)
                goto ccw_err;
        lcs_group_driver.driver.groups = lcs_drv_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");
        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");