usbatm.h

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/******************************************************************************
 *  usbatm.h - Generic USB xDSL driver core
 *
 *  Copyright (C) 2001, Alcatel
 *  Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas
 *  Copyright (C) 2004, David Woodhouse
 *
 *  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 of the License, 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., 59
 *  Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 ******************************************************************************/

#ifndef _USBATM_H_
#define _USBATM_H_

#include <linux/atm.h>
#include <linux/atmdev.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/stringify.h>
#include <linux/usb.h>
#include <linux/mutex.h>

/*
#define VERBOSE_DEBUG
*/

#ifdef DEBUG
#define UDSL_ASSERT(instance, x)    BUG_ON(!(x))
#else
#define UDSL_ASSERT(instance, x)                    \
    do {    \
        if (!(x))                       \
            dev_warn(&(instance)->usb_intf->dev,        \
                 "failed assertion '%s' at line %d",    \
                 __stringify(x), __LINE__);     \
    } while (0)
#endif

#define usb_err(instance, format, arg...)   \
    dev_err(&(instance)->usb_intf->dev , format , ## arg)
#define usb_info(instance, format, arg...)  \
    dev_info(&(instance)->usb_intf->dev , format , ## arg)
#define usb_warn(instance, format, arg...)  \
    dev_warn(&(instance)->usb_intf->dev , format , ## arg)
#ifdef DEBUG
#define usb_dbg(instance, format, arg...)   \
    dev_printk(KERN_DEBUG , &(instance)->usb_intf->dev , format , ## arg)
#else
#define usb_dbg(instance, format, arg...)   \
    do {} while (0)
#endif

/* FIXME: move to dev_* once ATM is driver model aware */
#define atm_printk(level, instance, format, arg...) \
    printk(level "ATM dev %d: " format ,        \
    (instance)->atm_dev->number , ## arg)

#define atm_err(instance, format, arg...)   \
    atm_printk(KERN_ERR, instance , format , ## arg)
#define atm_info(instance, format, arg...)  \
    atm_printk(KERN_INFO, instance , format , ## arg)
#define atm_warn(instance, format, arg...)  \
    atm_printk(KERN_WARNING, instance , format , ## arg)
#ifdef DEBUG
#define atm_dbg(instance, format, arg...)   \
    atm_printk(KERN_DEBUG, instance , format , ## arg)
#define atm_rldbg(instance, format, arg...) \
    if (printk_ratelimit())             \
        atm_printk(KERN_DEBUG, instance , format , ## arg)
#else
#define atm_dbg(instance, format, arg...)   \
    do {} while (0)
#define atm_rldbg(instance, format, arg...) \
    do {} while (0)
#endif


/* flags, set by mini-driver in bind() */

#define UDSL_SKIP_HEAVY_INIT    (1<<0)
#define UDSL_USE_ISOC       (1<<1)
#define UDSL_IGNORE_EILSEQ  (1<<2)


/* mini driver */

struct usbatm_data;

/*
*  Assuming all methods exist and succeed, they are called in this order:
*
*   bind, heavy_init, atm_start, ..., atm_stop, unbind
*/

struct usbatm_driver {
    const char *driver_name;

    /* init device ... can sleep, or cause probe() failure */
    int (*bind) (struct usbatm_data *, struct usb_interface *,
             const struct usb_device_id *id);

    /* additional device initialization that is too slow to be done in probe() */
    int (*heavy_init) (struct usbatm_data *, struct usb_interface *);

    /* cleanup device ... can sleep, but can't fail */
    void (*unbind) (struct usbatm_data *, struct usb_interface *);

    /* init ATM device ... can sleep, or cause ATM initialization failure */
    int (*atm_start) (struct usbatm_data *, struct atm_dev *);

    /* cleanup ATM device ... can sleep, but can't fail */
    void (*atm_stop) (struct usbatm_data *, struct atm_dev *);

    int bulk_in;    /* bulk rx endpoint */
    int isoc_in;    /* isochronous rx endpoint */
    int bulk_out;   /* bulk tx endpoint */

    unsigned rx_padding;
    unsigned tx_padding;
};

extern int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id,
        struct usbatm_driver *driver);
extern void usbatm_usb_disconnect(struct usb_interface *intf);


struct usbatm_channel {
    int endpoint;           /* usb pipe */
    unsigned int stride;        /* ATM cell size + padding */
    unsigned int buf_size;      /* urb buffer size */
    unsigned int packet_size;   /* endpoint maxpacket */
    spinlock_t lock;
    struct list_head list;
    struct tasklet_struct tasklet;
    struct timer_list delay;
    struct usbatm_data *usbatm;
};

/* main driver data */

struct usbatm_data {
    /******************
    *  public fields  *
    ******************/

    /* mini driver */
    struct usbatm_driver *driver;
    void *driver_data;
    char driver_name[16];
    unsigned int flags; /* set by mini-driver in bind() */

    /* USB device */
    struct usb_device *usb_dev;
    struct usb_interface *usb_intf;
    char description[64];

    /* ATM device */
    struct atm_dev *atm_dev;

    /********************************
    *  private fields - do not use  *
    ********************************/

    struct kref refcount;
    struct mutex serialize;
    int disconnected;

    /* heavy init */
    struct task_struct *thread;
    struct completion thread_started;
    struct completion thread_exited;

    /* ATM device */
    struct list_head vcc_list;

    struct usbatm_channel rx_channel;
    struct usbatm_channel tx_channel;

    struct sk_buff_head sndqueue;
    struct sk_buff *current_skb;    /* being emptied */

    struct usbatm_vcc_data *cached_vcc;
    int cached_vci;
    short cached_vpi;

    unsigned char *cell_buf;    /* holds partial rx cell */
    unsigned int buf_usage;

    struct urb *urbs[0];
};

static inline void *to_usbatm_driver_data(struct usb_interface *intf)
{
    struct usbatm_data *usbatm_instance;

    if (intf == NULL)
        return NULL;

    usbatm_instance = usb_get_intfdata(intf);

    if (usbatm_instance == NULL) /* set NULL before unbind() */
        return NULL;

    return usbatm_instance->driver_data; /* set NULL after unbind() */
}

#endif  /* _USBATM_H_ */