/* SPDX-License-Identifier: GPL-2.0+ */
/******************************************************************************
 *  usbatm.h - Generic USB xDSL driver core
 *
 *  Copyright (C) 2001, Alcatel
 *  Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas
 *  Copyright (C) 2004, David Woodhouse
 ******************************************************************************/

#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>
#include <linux/ratelimit.h>

/*
#define VERBOSE_DEBUG
*/

#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)
#define usb_dbg(instance, format, arg...)       \
        dev_dbg(&(instance)->usb_intf->dev , format , ## arg)

/* 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)
#define atm_dbg(instance, format, ...)                                  \
        pr_debug("ATM dev %d: " format,                                 \
                 (instance)->atm_dev->number, ##__VA_ARGS__)
#define atm_rldbg(instance, format, ...)                                \
        pr_debug_ratelimited("ATM dev %d: " format,                     \
                             (instance)->atm_dev->number, ##__VA_ARGS__)

/* 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[];
};

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_ */