/* $Id: kcapi.c,v 1.1.2.8 2004/03/26 19:57:20 armin Exp $
 *
 * Kernel CAPI 2.0 Module
 *
 * Copyright 1999 by Carsten Paeth <calle@calle.de>
 * Copyright 2002 by Kai Germaschewski <kai@germaschewski.name>
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

#include "kcapi.h"
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/sched/signal.h>
#include <linux/seq_file.h>
#include <linux/skbuff.h>
#include <linux/workqueue.h>
#include <linux/capi.h>
#include <linux/kernelcapi.h>
#include <linux/init.h>
#include <linux/moduleparam.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/isdn/capicmd.h>
#include <linux/isdn/capiutil.h>
#include <linux/mutex.h>
#include <linux/rcupdate.h>

static int showcapimsgs;
static struct workqueue_struct *kcapi_wq;

module_param(showcapimsgs, uint, 0);

/* ------------------------------------------------------------- */

struct capictr_event {
        struct work_struct work;
        unsigned int type;
        u32 controller;
};

/* ------------------------------------------------------------- */

static const struct capi_version driver_version = {2, 0, 1, 1 << 4};
static char driver_serial[CAPI_SERIAL_LEN] = "0004711";
static char capi_manufakturer[64] = "AVM Berlin";

#define NCCI2CTRL(ncci)    (((ncci) >> 24) & 0x7f)

struct capi_ctr *capi_controller[CAPI_MAXCONTR];
DEFINE_MUTEX(capi_controller_lock);

struct capi20_appl *capi_applications[CAPI_MAXAPPL];

static int ncontrollers;

/* -------- controller ref counting -------------------------------------- */

static inline struct capi_ctr *
capi_ctr_get(struct capi_ctr *ctr)
{
        if (!try_module_get(ctr->owner))
                return NULL;
        return ctr;
}

static inline void
capi_ctr_put(struct capi_ctr *ctr)
{
        module_put(ctr->owner);
}

/* ------------------------------------------------------------- */

static inline struct capi_ctr *get_capi_ctr_by_nr(u16 contr)
{
        if (contr < 1 || contr - 1 >= CAPI_MAXCONTR)
                return NULL;

        return capi_controller[contr - 1];
}

static inline struct capi20_appl *__get_capi_appl_by_nr(u16 applid)
{
        lockdep_assert_held(&capi_controller_lock);

        if (applid < 1 || applid - 1 >= CAPI_MAXAPPL)
                return NULL;

        return capi_applications[applid - 1];
}

static inline struct capi20_appl *get_capi_appl_by_nr(u16 applid)
{
        if (applid < 1 || applid - 1 >= CAPI_MAXAPPL)
                return NULL;

        return rcu_dereference(capi_applications[applid - 1]);
}

/* -------- util functions ------------------------------------ */

static inline int capi_cmd_valid(u8 cmd)
{
        switch (cmd) {
        case CAPI_ALERT:
        case CAPI_CONNECT:
        case CAPI_CONNECT_ACTIVE:
        case CAPI_CONNECT_B3_ACTIVE:
        case CAPI_CONNECT_B3:
        case CAPI_CONNECT_B3_T90_ACTIVE:
        case CAPI_DATA_B3:
        case CAPI_DISCONNECT_B3:
        case CAPI_DISCONNECT:
        case CAPI_FACILITY:
        case CAPI_INFO:
        case CAPI_LISTEN:
        case CAPI_MANUFACTURER:
        case CAPI_RESET_B3:
        case CAPI_SELECT_B_PROTOCOL:
                return 1;
        }
        return 0;
}

static inline int capi_subcmd_valid(u8 subcmd)
{
        switch (subcmd) {
        case CAPI_REQ:
        case CAPI_CONF:
        case CAPI_IND:
        case CAPI_RESP:
                return 1;
        }
        return 0;
}

/* ------------------------------------------------------------ */

static void
register_appl(struct capi_ctr *ctr, u16 applid, capi_register_params *rparam)
{
        ctr = capi_ctr_get(ctr);

        if (ctr)
                ctr->register_appl(ctr, applid, rparam);
        else
                printk(KERN_WARNING "%s: cannot get controller resources\n",
                       __func__);
}


static void release_appl(struct capi_ctr *ctr, u16 applid)
{
        DBG("applid %#x", applid);

        ctr->release_appl(ctr, applid);
        capi_ctr_put(ctr);
}

static void notify_up(u32 contr)
{
        struct capi20_appl *ap;
        struct capi_ctr *ctr;
        u16 applid;

        mutex_lock(&capi_controller_lock);

        if (showcapimsgs & 1)
                printk(KERN_DEBUG "kcapi: notify up contr %d\n", contr);

        ctr = get_capi_ctr_by_nr(contr);
        if (ctr) {
                if (ctr->state == CAPI_CTR_RUNNING)
                        goto unlock_out;

                ctr->state = CAPI_CTR_RUNNING;

                for (applid = 1; applid <= CAPI_MAXAPPL; applid++) {
                        ap = __get_capi_appl_by_nr(applid);
                        if (ap)
                                register_appl(ctr, applid, &ap->rparam);
                }
        } else
                printk(KERN_WARNING "%s: invalid contr %d\n", __func__, contr);

unlock_out:
        mutex_unlock(&capi_controller_lock);
}

static void ctr_down(struct capi_ctr *ctr, int new_state)
{
        struct capi20_appl *ap;
        u16 applid;

        if (ctr->state == CAPI_CTR_DETECTED || ctr->state == CAPI_CTR_DETACHED)
                return;

        ctr->state = new_state;

        memset(ctr->manu, 0, sizeof(ctr->manu));
        memset(&ctr->version, 0, sizeof(ctr->version));
        memset(&ctr->profile, 0, sizeof(ctr->profile));
        memset(ctr->serial, 0, sizeof(ctr->serial));

        for (applid = 1; applid <= CAPI_MAXAPPL; applid++) {
                ap = __get_capi_appl_by_nr(applid);
                if (ap)
                        capi_ctr_put(ctr);
        }
}

static void notify_down(u32 contr)
{
        struct capi_ctr *ctr;

        mutex_lock(&capi_controller_lock);

        if (showcapimsgs & 1)
                printk(KERN_DEBUG "kcapi: notify down contr %d\n", contr);

        ctr = get_capi_ctr_by_nr(contr);
        if (ctr)
                ctr_down(ctr, CAPI_CTR_DETECTED);
        else
                printk(KERN_WARNING "%s: invalid contr %d\n", __func__, contr);

        mutex_unlock(&capi_controller_lock);
}

static void do_notify_work(struct work_struct *work)
{
        struct capictr_event *event =
                container_of(work, struct capictr_event, work);

        switch (event->type) {
        case CAPICTR_UP:
                notify_up(event->controller);
                break;
        case CAPICTR_DOWN:
                notify_down(event->controller);
                break;
        }

        kfree(event);
}

static int notify_push(unsigned int event_type, u32 controller)
{
        struct capictr_event *event = kmalloc_obj(*event, GFP_ATOMIC);

        if (!event)
                return -ENOMEM;

        INIT_WORK(&event->work, do_notify_work);
        event->type = event_type;
        event->controller = controller;

        queue_work(kcapi_wq, &event->work);
        return 0;
}

/* -------- Receiver ------------------------------------------ */

static void recv_handler(struct work_struct *work)
{
        struct sk_buff *skb;
        struct capi20_appl *ap =
                container_of(work, struct capi20_appl, recv_work);

        if ((!ap) || (ap->release_in_progress))
                return;

        mutex_lock(&ap->recv_mtx);
        while ((skb = skb_dequeue(&ap->recv_queue))) {
                if (CAPIMSG_CMD(skb->data) == CAPI_DATA_B3_IND)
                        ap->nrecvdatapkt++;
                else
                        ap->nrecvctlpkt++;

                ap->recv_message(ap, skb);
        }
        mutex_unlock(&ap->recv_mtx);
}

/**
 * capi_ctr_handle_message() - handle incoming CAPI message
 * @ctr:        controller descriptor structure.
 * @appl:       application ID.
 * @skb:        message.
 *
 * Called by hardware driver to pass a CAPI message to the application.
 */

void capi_ctr_handle_message(struct capi_ctr *ctr, u16 appl,
                             struct sk_buff *skb)
{
        struct capi20_appl *ap;
        int showctl = 0;
        u8 cmd, subcmd;
        _cdebbuf *cdb;

        if (ctr->state != CAPI_CTR_RUNNING) {
                cdb = capi_message2str(skb->data);
                if (cdb) {
                        printk(KERN_INFO "kcapi: controller [%03d] not active, got: %s",
                               ctr->cnr, cdb->buf);
                        cdebbuf_free(cdb);
                } else
                        printk(KERN_INFO "kcapi: controller [%03d] not active, cannot trace\n",
                               ctr->cnr);
                goto error;
        }

        cmd = CAPIMSG_COMMAND(skb->data);
        subcmd = CAPIMSG_SUBCOMMAND(skb->data);
        if (cmd == CAPI_DATA_B3 && subcmd == CAPI_IND) {
                ctr->nrecvdatapkt++;
                if (ctr->traceflag > 2)
                        showctl |= 2;
        } else {
                ctr->nrecvctlpkt++;
                if (ctr->traceflag)
                        showctl |= 2;
        }
        showctl |= (ctr->traceflag & 1);
        if (showctl & 2) {
                if (showctl & 1) {
                        printk(KERN_DEBUG "kcapi: got [%03d] id#%d %s len=%u\n",
                               ctr->cnr, CAPIMSG_APPID(skb->data),
                               capi_cmd2str(cmd, subcmd),
                               CAPIMSG_LEN(skb->data));
                } else {
                        cdb = capi_message2str(skb->data);
                        if (cdb) {
                                printk(KERN_DEBUG "kcapi: got [%03d] %s\n",
                                       ctr->cnr, cdb->buf);
                                cdebbuf_free(cdb);
                        } else
                                printk(KERN_DEBUG "kcapi: got [%03d] id#%d %s len=%u, cannot trace\n",
                                       ctr->cnr, CAPIMSG_APPID(skb->data),
                                       capi_cmd2str(cmd, subcmd),
                                       CAPIMSG_LEN(skb->data));
                }

        }

        rcu_read_lock();
        ap = get_capi_appl_by_nr(CAPIMSG_APPID(skb->data));
        if (!ap) {
                rcu_read_unlock();
                cdb = capi_message2str(skb->data);
                if (cdb) {
                        printk(KERN_ERR "kcapi: handle_message: applid %d state released (%s)\n",
                               CAPIMSG_APPID(skb->data), cdb->buf);
                        cdebbuf_free(cdb);
                } else
                        printk(KERN_ERR "kcapi: handle_message: applid %d state released (%s) cannot trace\n",
                               CAPIMSG_APPID(skb->data),
                               capi_cmd2str(cmd, subcmd));
                goto error;
        }
        skb_queue_tail(&ap->recv_queue, skb);
        queue_work(kcapi_wq, &ap->recv_work);
        rcu_read_unlock();

        return;

error:
        kfree_skb(skb);
}

EXPORT_SYMBOL(capi_ctr_handle_message);

/**
 * capi_ctr_ready() - signal CAPI controller ready
 * @ctr:        controller descriptor structure.
 *
 * Called by hardware driver to signal that the controller is up and running.
 */

void capi_ctr_ready(struct capi_ctr *ctr)
{
        printk(KERN_NOTICE "kcapi: controller [%03d] \"%s\" ready.\n",
               ctr->cnr, ctr->name);

        notify_push(CAPICTR_UP, ctr->cnr);
}

EXPORT_SYMBOL(capi_ctr_ready);

/**
 * capi_ctr_down() - signal CAPI controller not ready
 * @ctr:        controller descriptor structure.
 *
 * Called by hardware driver to signal that the controller is down and
 * unavailable for use.
 */

void capi_ctr_down(struct capi_ctr *ctr)
{
        printk(KERN_NOTICE "kcapi: controller [%03d] down.\n", ctr->cnr);

        notify_push(CAPICTR_DOWN, ctr->cnr);
}

EXPORT_SYMBOL(capi_ctr_down);

/* ------------------------------------------------------------- */

/**
 * attach_capi_ctr() - register CAPI controller
 * @ctr:        controller descriptor structure.
 *
 * Called by hardware driver to register a controller with the CAPI subsystem.
 * Return value: 0 on success, error code < 0 on error
 */

int attach_capi_ctr(struct capi_ctr *ctr)
{
        int i;

        mutex_lock(&capi_controller_lock);

        for (i = 0; i < CAPI_MAXCONTR; i++) {
                if (!capi_controller[i])
                        break;
        }
        if (i == CAPI_MAXCONTR) {
                mutex_unlock(&capi_controller_lock);
                printk(KERN_ERR "kcapi: out of controller slots\n");
                return -EBUSY;
        }
        capi_controller[i] = ctr;

        ctr->nrecvctlpkt = 0;
        ctr->nrecvdatapkt = 0;
        ctr->nsentctlpkt = 0;
        ctr->nsentdatapkt = 0;
        ctr->cnr = i + 1;
        ctr->state = CAPI_CTR_DETECTED;
        ctr->blocked = 0;
        ctr->traceflag = showcapimsgs;

        sprintf(ctr->procfn, "capi/controllers/%d", ctr->cnr);
        ctr->procent = proc_create_single_data(ctr->procfn, 0, NULL,
                        ctr->proc_show, ctr);

        ncontrollers++;

        mutex_unlock(&capi_controller_lock);

        printk(KERN_NOTICE "kcapi: controller [%03d]: %s attached\n",
               ctr->cnr, ctr->name);
        return 0;
}

EXPORT_SYMBOL(attach_capi_ctr);

/**
 * detach_capi_ctr() - unregister CAPI controller
 * @ctr:        controller descriptor structure.
 *
 * Called by hardware driver to remove the registration of a controller
 * with the CAPI subsystem.
 * Return value: 0 on success, error code < 0 on error
 */

int detach_capi_ctr(struct capi_ctr *ctr)
{
        int err = 0;

        mutex_lock(&capi_controller_lock);

        ctr_down(ctr, CAPI_CTR_DETACHED);

        if (ctr->cnr < 1 || ctr->cnr - 1 >= CAPI_MAXCONTR) {
                err = -EINVAL;
                goto unlock_out;
        }

        if (capi_controller[ctr->cnr - 1] != ctr) {
                err = -EINVAL;
                goto unlock_out;
        }
        capi_controller[ctr->cnr - 1] = NULL;
        ncontrollers--;

        if (ctr->procent)
                remove_proc_entry(ctr->procfn, NULL);

        printk(KERN_NOTICE "kcapi: controller [%03d]: %s unregistered\n",
               ctr->cnr, ctr->name);

unlock_out:
        mutex_unlock(&capi_controller_lock);

        return err;
}

EXPORT_SYMBOL(detach_capi_ctr);

/* ------------------------------------------------------------- */
/* -------- CAPI2.0 Interface ---------------------------------- */
/* ------------------------------------------------------------- */

/**
 * capi20_isinstalled() - CAPI 2.0 operation CAPI_INSTALLED
 *
 * Return value: CAPI result code (CAPI_NOERROR if at least one ISDN controller
 *      is ready for use, CAPI_REGNOTINSTALLED otherwise)
 */

u16 capi20_isinstalled(void)
{
        u16 ret = CAPI_REGNOTINSTALLED;
        int i;

        mutex_lock(&capi_controller_lock);

        for (i = 0; i < CAPI_MAXCONTR; i++)
                if (capi_controller[i] &&
                    capi_controller[i]->state == CAPI_CTR_RUNNING) {
                        ret = CAPI_NOERROR;
                        break;
                }

        mutex_unlock(&capi_controller_lock);

        return ret;
}

/**
 * capi20_register() - CAPI 2.0 operation CAPI_REGISTER
 * @ap:         CAPI application descriptor structure.
 *
 * Register an application's presence with CAPI.
 * A unique application ID is assigned and stored in @ap->applid.
 * After this function returns successfully, the message receive
 * callback function @ap->recv_message() may be called at any time
 * until capi20_release() has been called for the same @ap.
 * Return value: CAPI result code
 */

u16 capi20_register(struct capi20_appl *ap)
{
        int i;
        u16 applid;

        DBG("");

        if (ap->rparam.datablklen < 128)
                return CAPI_LOGBLKSIZETOSMALL;

        ap->nrecvctlpkt = 0;
        ap->nrecvdatapkt = 0;
        ap->nsentctlpkt = 0;
        ap->nsentdatapkt = 0;
        mutex_init(&ap->recv_mtx);
        skb_queue_head_init(&ap->recv_queue);
        INIT_WORK(&ap->recv_work, recv_handler);
        ap->release_in_progress = 0;

        mutex_lock(&capi_controller_lock);

        for (applid = 1; applid <= CAPI_MAXAPPL; applid++) {
                if (capi_applications[applid - 1] == NULL)
                        break;
        }
        if (applid > CAPI_MAXAPPL) {
                mutex_unlock(&capi_controller_lock);
                return CAPI_TOOMANYAPPLS;
        }

        ap->applid = applid;
        capi_applications[applid - 1] = ap;

        for (i = 0; i < CAPI_MAXCONTR; i++) {
                if (!capi_controller[i] ||
                    capi_controller[i]->state != CAPI_CTR_RUNNING)
                        continue;
                register_appl(capi_controller[i], applid, &ap->rparam);
        }

        mutex_unlock(&capi_controller_lock);

        if (showcapimsgs & 1) {
                printk(KERN_DEBUG "kcapi: appl %d up\n", applid);
        }

        return CAPI_NOERROR;
}

/**
 * capi20_release() - CAPI 2.0 operation CAPI_RELEASE
 * @ap:         CAPI application descriptor structure.
 *
 * Terminate an application's registration with CAPI.
 * After this function returns successfully, the message receive
 * callback function @ap->recv_message() will no longer be called.
 * Return value: CAPI result code
 */

u16 capi20_release(struct capi20_appl *ap)
{
        int i;

        DBG("applid %#x", ap->applid);

        mutex_lock(&capi_controller_lock);

        ap->release_in_progress = 1;
        capi_applications[ap->applid - 1] = NULL;

        synchronize_rcu();

        for (i = 0; i < CAPI_MAXCONTR; i++) {
                if (!capi_controller[i] ||
                    capi_controller[i]->state != CAPI_CTR_RUNNING)
                        continue;
                release_appl(capi_controller[i], ap->applid);
        }

        mutex_unlock(&capi_controller_lock);

        flush_workqueue(kcapi_wq);
        skb_queue_purge(&ap->recv_queue);

        if (showcapimsgs & 1) {
                printk(KERN_DEBUG "kcapi: appl %d down\n", ap->applid);
        }

        return CAPI_NOERROR;
}

/**
 * capi20_put_message() - CAPI 2.0 operation CAPI_PUT_MESSAGE
 * @ap:         CAPI application descriptor structure.
 * @skb:        CAPI message.
 *
 * Transfer a single message to CAPI.
 * Return value: CAPI result code
 */

u16 capi20_put_message(struct capi20_appl *ap, struct sk_buff *skb)
{
        struct capi_ctr *ctr;
        int showctl = 0;
        u8 cmd, subcmd;

        DBG("applid %#x", ap->applid);

        if (ncontrollers == 0)
                return CAPI_REGNOTINSTALLED;
        if ((ap->applid == 0) || ap->release_in_progress)
                return CAPI_ILLAPPNR;
        if (skb->len < 12
            || !capi_cmd_valid(CAPIMSG_COMMAND(skb->data))
            || !capi_subcmd_valid(CAPIMSG_SUBCOMMAND(skb->data)))
                return CAPI_ILLCMDORSUBCMDORMSGTOSMALL;

        /*
         * The controller reference is protected by the existence of the
         * application passed to us. We assume that the caller properly
         * synchronizes this service with capi20_release.
         */
        ctr = get_capi_ctr_by_nr(CAPIMSG_CONTROLLER(skb->data));
        if (!ctr || ctr->state != CAPI_CTR_RUNNING)
                return CAPI_REGNOTINSTALLED;
        if (ctr->blocked)
                return CAPI_SENDQUEUEFULL;

        cmd = CAPIMSG_COMMAND(skb->data);
        subcmd = CAPIMSG_SUBCOMMAND(skb->data);

        if (cmd == CAPI_DATA_B3 && subcmd == CAPI_REQ) {
                ctr->nsentdatapkt++;
                ap->nsentdatapkt++;
                if (ctr->traceflag > 2)
                        showctl |= 2;
        } else {
                ctr->nsentctlpkt++;
                ap->nsentctlpkt++;
                if (ctr->traceflag)
                        showctl |= 2;
        }
        showctl |= (ctr->traceflag & 1);
        if (showctl & 2) {
                if (showctl & 1) {
                        printk(KERN_DEBUG "kcapi: put [%03d] id#%d %s len=%u\n",
                               CAPIMSG_CONTROLLER(skb->data),
                               CAPIMSG_APPID(skb->data),
                               capi_cmd2str(cmd, subcmd),
                               CAPIMSG_LEN(skb->data));
                } else {
                        _cdebbuf *cdb = capi_message2str(skb->data);
                        if (cdb) {
                                printk(KERN_DEBUG "kcapi: put [%03d] %s\n",
                                       CAPIMSG_CONTROLLER(skb->data),
                                       cdb->buf);
                                cdebbuf_free(cdb);
                        } else
                                printk(KERN_DEBUG "kcapi: put [%03d] id#%d %s len=%u cannot trace\n",
                                       CAPIMSG_CONTROLLER(skb->data),
                                       CAPIMSG_APPID(skb->data),
                                       capi_cmd2str(cmd, subcmd),
                                       CAPIMSG_LEN(skb->data));
                }
        }
        return ctr->send_message(ctr, skb);
}

/**
 * capi20_get_manufacturer() - CAPI 2.0 operation CAPI_GET_MANUFACTURER
 * @contr:      controller number.
 * @buf:        result buffer (64 bytes).
 *
 * Retrieve information about the manufacturer of the specified ISDN controller
 * or (for @contr == 0) the driver itself.
 * Return value: CAPI result code
 */

u16 capi20_get_manufacturer(u32 contr, u8 buf[CAPI_MANUFACTURER_LEN])
{
        struct capi_ctr *ctr;
        u16 ret;

        if (contr == 0) {
                strscpy_pad(buf, capi_manufakturer, CAPI_MANUFACTURER_LEN);
                return CAPI_NOERROR;
        }

        mutex_lock(&capi_controller_lock);

        ctr = get_capi_ctr_by_nr(contr);
        if (ctr && ctr->state == CAPI_CTR_RUNNING) {
                strscpy_pad(buf, ctr->manu, CAPI_MANUFACTURER_LEN);
                ret = CAPI_NOERROR;
        } else
                ret = CAPI_REGNOTINSTALLED;

        mutex_unlock(&capi_controller_lock);
        return ret;
}

/**
 * capi20_get_version() - CAPI 2.0 operation CAPI_GET_VERSION
 * @contr:      controller number.
 * @verp:       result structure.
 *
 * Retrieve version information for the specified ISDN controller
 * or (for @contr == 0) the driver itself.
 * Return value: CAPI result code
 */

u16 capi20_get_version(u32 contr, struct capi_version *verp)
{
        struct capi_ctr *ctr;
        u16 ret;

        if (contr == 0) {
                *verp = driver_version;
                return CAPI_NOERROR;
        }

        mutex_lock(&capi_controller_lock);

        ctr = get_capi_ctr_by_nr(contr);
        if (ctr && ctr->state == CAPI_CTR_RUNNING) {
                memcpy(verp, &ctr->version, sizeof(capi_version));
                ret = CAPI_NOERROR;
        } else
                ret = CAPI_REGNOTINSTALLED;

        mutex_unlock(&capi_controller_lock);
        return ret;
}

/**
 * capi20_get_serial() - CAPI 2.0 operation CAPI_GET_SERIAL_NUMBER
 * @contr:      controller number.
 * @serial:     result buffer (8 bytes).
 *
 * Retrieve the serial number of the specified ISDN controller
 * or (for @contr == 0) the driver itself.
 * Return value: CAPI result code
 */

u16 capi20_get_serial(u32 contr, u8 serial[CAPI_SERIAL_LEN])
{
        struct capi_ctr *ctr;
        u16 ret;

        if (contr == 0) {
                strscpy(serial, driver_serial, CAPI_SERIAL_LEN);
                return CAPI_NOERROR;
        }

        mutex_lock(&capi_controller_lock);

        ctr = get_capi_ctr_by_nr(contr);
        if (ctr && ctr->state == CAPI_CTR_RUNNING) {
                strscpy(serial, ctr->serial, CAPI_SERIAL_LEN);
                ret = CAPI_NOERROR;
        } else
                ret = CAPI_REGNOTINSTALLED;

        mutex_unlock(&capi_controller_lock);
        return ret;
}

/**
 * capi20_get_profile() - CAPI 2.0 operation CAPI_GET_PROFILE
 * @contr:      controller number.
 * @profp:      result structure.
 *
 * Retrieve capability information for the specified ISDN controller
 * or (for @contr == 0) the number of installed controllers.
 * Return value: CAPI result code
 */

u16 capi20_get_profile(u32 contr, struct capi_profile *profp)
{
        struct capi_ctr *ctr;
        u16 ret;

        if (contr == 0) {
                profp->ncontroller = ncontrollers;
                return CAPI_NOERROR;
        }

        mutex_lock(&capi_controller_lock);

        ctr = get_capi_ctr_by_nr(contr);
        if (ctr && ctr->state == CAPI_CTR_RUNNING) {
                memcpy(profp, &ctr->profile, sizeof(struct capi_profile));
                ret = CAPI_NOERROR;
        } else
                ret = CAPI_REGNOTINSTALLED;

        mutex_unlock(&capi_controller_lock);
        return ret;
}

/**
 * capi20_manufacturer() - CAPI 2.0 operation CAPI_MANUFACTURER
 * @cmd:        command.
 * @data:       parameter.
 *
 * Perform manufacturer specific command.
 * Return value: CAPI result code
 */

int capi20_manufacturer(unsigned long cmd, void __user *data)
{
        struct capi_ctr *ctr;
        int retval;

        switch (cmd) {
        case KCAPI_CMD_TRACE:
        {
                kcapi_flagdef fdef;

                if (copy_from_user(&fdef, data, sizeof(kcapi_flagdef)))
                        return -EFAULT;

                mutex_lock(&capi_controller_lock);

                ctr = get_capi_ctr_by_nr(fdef.contr);
                if (ctr) {
                        ctr->traceflag = fdef.flag;
                        printk(KERN_INFO "kcapi: contr [%03d] set trace=%d\n",
                               ctr->cnr, ctr->traceflag);
                        retval = 0;
                } else
                        retval = -ESRCH;

                mutex_unlock(&capi_controller_lock);

                return retval;
        }

        default:
                printk(KERN_ERR "kcapi: manufacturer command %lu unknown.\n",
                       cmd);
                break;

        }
        return -EINVAL;
}

/* ------------------------------------------------------------- */
/* -------- Init & Cleanup ------------------------------------- */
/* ------------------------------------------------------------- */

/*
 * init / exit functions
 */

int __init kcapi_init(void)
{
        int err;

        kcapi_wq = alloc_workqueue("kcapi", WQ_PERCPU, 0);
        if (!kcapi_wq)
                return -ENOMEM;

        err = cdebug_init();
        if (err) {
                destroy_workqueue(kcapi_wq);
                return err;
        }

        if (IS_ENABLED(CONFIG_PROC_FS))
                kcapi_proc_init();

        return 0;
}

void kcapi_exit(void)
{
        if (IS_ENABLED(CONFIG_PROC_FS))
                kcapi_proc_exit();

        cdebug_exit();
        destroy_workqueue(kcapi_wq);
}