/*
 * Driver for ST5481 USB ISDN modem
 *
 * Author       Frode Isaksen
 * Copyright    2001 by Frode Isaksen      <fisaksen@bewan.com>
 *              2001 by Kai Germaschewski  <kai.germaschewski@gmx.de>
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

#ifndef _ST5481_H_
#define _ST5481_H_


// USB IDs, the Product Id is in the range 0x4810-0x481F

#define ST_VENDOR_ID 0x0483
#define ST5481_PRODUCT_ID 0x4810
#define ST5481_PRODUCT_ID_MASK 0xFFF0

// ST5481 endpoints when using alternative setting 3 (2B+D).
// To get the endpoint address, OR with 0x80 for IN endpoints.

#define EP_CTRL   0x00U /* Control endpoint */
#define EP_INT    0x01U /* Interrupt endpoint */
#define EP_B1_OUT 0x02U /* B1 channel out */
#define EP_B1_IN  0x03U /* B1 channel in */
#define EP_B2_OUT 0x04U /* B2 channel out */
#define EP_B2_IN  0x05U /* B2 channel in */
#define EP_D_OUT  0x06U /* D channel out */
#define EP_D_IN   0x07U /* D channel in */

// Number of isochronous packets. With 20 packets we get
// 50 interrupts/sec for each endpoint.

#define NUM_ISO_PACKETS_D      20
#define NUM_ISO_PACKETS_B      20

// Size of each isochronous packet.
// In outgoing direction we need to match ISDN data rates:
// D:  2 bytes / msec -> 16 kbit / s
// B: 16 bytes / msec -> 64 kbit / s
#define SIZE_ISO_PACKETS_D_IN  16
#define SIZE_ISO_PACKETS_D_OUT 2
#define SIZE_ISO_PACKETS_B_IN  32
#define SIZE_ISO_PACKETS_B_OUT 8

// If we overrun/underrun, we send one packet with +/- 2 bytes
#define B_FLOW_ADJUST 2

// Registers that are written using vendor specific device request
// on endpoint 0.

#define LBA                     0x02 /* S loopback */
#define SET_DEFAULT             0x06 /* Soft reset */
#define LBB                     0x1D /* S maintenance loopback */
#define STT                     0x1e /* S force transmission signals */
#define SDA_MIN                 0x20 /* SDA-sin minimal value */
#define SDA_MAX                 0x21 /* SDA-sin maximal value */
#define SDELAY_VALUE            0x22 /* Delay between Tx and Rx clock */
#define IN_D_COUNTER            0x36 /* D receive channel fifo counter */
#define OUT_D_COUNTER           0x37 /* D transmit channel fifo counter */
#define IN_B1_COUNTER           0x38 /* B1 receive channel fifo counter */
#define OUT_B1_COUNTER          0x39 /* B1 transmit channel fifo counter */
#define IN_B2_COUNTER           0x3a /* B2 receive channel fifo counter */
#define OUT_B2_COUNTER          0x3b /* B2 transmit channel fifo counter */
#define FFCTRL_IN_D             0x3C /* D receive channel fifo threshold low */
#define FFCTRH_IN_D             0x3D /* D receive channel fifo threshold high */
#define FFCTRL_OUT_D            0x3E /* D transmit channel fifo threshold low */
#define FFCTRH_OUT_D            0x3F /* D transmit channel fifo threshold high */
#define FFCTRL_IN_B1            0x40 /* B1 receive channel fifo threshold low */
#define FFCTRH_IN_B1            0x41 /* B1 receive channel fifo threshold high */
#define FFCTRL_OUT_B1           0x42 /* B1 transmit channel fifo threshold low */
#define FFCTRH_OUT_B1           0x43 /* B1 transmit channel fifo threshold high */
#define FFCTRL_IN_B2            0x44 /* B2 receive channel fifo threshold low */
#define FFCTRH_IN_B2            0x45 /* B2 receive channel fifo threshold high */
#define FFCTRL_OUT_B2           0x46 /* B2 transmit channel fifo threshold low */
#define FFCTRH_OUT_B2           0x47 /* B2 transmit channel fifo threshold high */
#define MPMSK                   0x4A /* Multi purpose interrupt MASK register */
#define FFMSK_D                 0x4c /* D fifo interrupt MASK register */
#define FFMSK_B1                0x4e /* B1 fifo interrupt MASK register */
#define FFMSK_B2                0x50 /* B2 fifo interrupt MASK register */
#define GPIO_DIR                0x52 /* GPIO pins direction registers */
#define GPIO_OUT                0x53 /* GPIO pins output register */
#define GPIO_IN                 0x54 /* GPIO pins input register */
#define TXCI                    0x56 /* CI command to be transmitted */


// Format of the interrupt packet received on endpoint 1:
//
// +--------+--------+--------+--------+--------+--------+
// !MPINT   !FFINT_D !FFINT_B1!FFINT_B2!CCIST   !GPIO_INT!
// +--------+--------+--------+--------+--------+--------+

// Offsets in the interrupt packet

#define MPINT                   0
#define FFINT_D                 1
#define FFINT_B1                2
#define FFINT_B2                3
#define CCIST                   4
#define GPIO_INT                5
#define INT_PKT_SIZE            6

// MPINT
#define LSD_INT                 0x80 /* S line activity detected */
#define RXCI_INT                0x40 /* Indicate primitive arrived */
#define DEN_INT                 0x20 /* Signal enabling data out of D Tx fifo */
#define DCOLL_INT               0x10 /* D channel collision */
#define AMIVN_INT               0x04 /* AMI violation number reached 2 */
#define INFOI_INT               0x04 /* INFOi changed */
#define DRXON_INT               0x02 /* Reception channel active */
#define GPCHG_INT               0x01 /* GPIO pin value changed */

// FFINT_x
#define IN_OVERRUN              0x80 /* In fifo overrun */
#define OUT_UNDERRUN            0x40 /* Out fifo underrun */
#define IN_UP                   0x20 /* In fifo thresholdh up-crossed */
#define IN_DOWN                 0x10 /* In fifo thresholdl down-crossed */
#define OUT_UP                  0x08 /* Out fifo thresholdh up-crossed */
#define OUT_DOWN                0x04 /* Out fifo thresholdl down-crossed */
#define IN_COUNTER_ZEROED       0x02 /* In down-counter reached 0 */
#define OUT_COUNTER_ZEROED      0x01 /* Out down-counter reached 0 */

#define ANY_REC_INT     (IN_OVERRUN + IN_UP + IN_DOWN + IN_COUNTER_ZEROED)
#define ANY_XMIT_INT    (OUT_UNDERRUN + OUT_UP + OUT_DOWN + OUT_COUNTER_ZEROED)


// Level 1 commands that are sent using the TXCI device request
#define ST5481_CMD_DR            0x0 /* Deactivation Request */
#define ST5481_CMD_RES           0x1 /* state machine RESet */
#define ST5481_CMD_TM1           0x2 /* Test Mode 1 */
#define ST5481_CMD_TM2           0x3 /* Test Mode 2 */
#define ST5481_CMD_PUP           0x7 /* Power UP */
#define ST5481_CMD_AR8           0x8 /* Activation Request class 1 */
#define ST5481_CMD_AR10          0x9 /* Activation Request class 2 */
#define ST5481_CMD_ARL           0xA /* Activation Request Loopback */
#define ST5481_CMD_PDN           0xF /* Power DoWn */

// Turn on/off the LEDs using the GPIO device request.
// To use the B LEDs, number_of_leds must be set to 4
#define B1_LED          0x10U
#define B2_LED          0x20U
#define GREEN_LED       0x40U
#define RED_LED         0x80U

// D channel out states
enum {
        ST_DOUT_NONE,

        ST_DOUT_SHORT_INIT,
        ST_DOUT_SHORT_WAIT_DEN,

        ST_DOUT_LONG_INIT,
        ST_DOUT_LONG_WAIT_DEN,
        ST_DOUT_NORMAL,

        ST_DOUT_WAIT_FOR_UNDERRUN,
        ST_DOUT_WAIT_FOR_NOT_BUSY,
        ST_DOUT_WAIT_FOR_STOP,
        ST_DOUT_WAIT_FOR_RESET,
};

#define DOUT_STATE_COUNT (ST_DOUT_WAIT_FOR_RESET + 1)

// D channel out events
enum {
        EV_DOUT_START_XMIT,
        EV_DOUT_COMPLETE,
        EV_DOUT_DEN,
        EV_DOUT_RESETED,
        EV_DOUT_STOPPED,
        EV_DOUT_COLL,
        EV_DOUT_UNDERRUN,
};

#define DOUT_EVENT_COUNT (EV_DOUT_UNDERRUN + 1)

// ----------------------------------------------------------------------

enum {
        ST_L1_F3,
        ST_L1_F4,
        ST_L1_F6,
        ST_L1_F7,
        ST_L1_F8,
};

#define L1_STATE_COUNT (ST_L1_F8 + 1)

// The first 16 entries match the Level 1 indications that
// are found at offset 4 (CCIST) in the interrupt packet

enum {
        EV_IND_DP,  // 0000 Deactivation Pending
        EV_IND_1,   // 0001
        EV_IND_2,   // 0010
        EV_IND_3,   // 0011
        EV_IND_RSY, // 0100 ReSYnchronizing
        EV_IND_5,   // 0101
        EV_IND_6,   // 0110
        EV_IND_7,   // 0111
        EV_IND_AP,  // 1000 Activation Pending
        EV_IND_9,   // 1001
        EV_IND_10,  // 1010
        EV_IND_11,  // 1011
        EV_IND_AI8, // 1100 Activation Indication class 8
        EV_IND_AI10,// 1101 Activation Indication class 10
        EV_IND_AIL, // 1110 Activation Indication Loopback
        EV_IND_DI,  // 1111 Deactivation Indication
        EV_PH_ACTIVATE_REQ,
        EV_PH_DEACTIVATE_REQ,
        EV_TIMER3,
};

#define L1_EVENT_COUNT (EV_TIMER3 + 1)

#define ERR(format, arg...)                                             \
        printk(KERN_ERR "%s:%s: " format "\n" , __FILE__,  __func__ , ## arg)

#define WARNING(format, arg...)                                         \
        printk(KERN_WARNING "%s:%s: " format "\n" , __FILE__,  __func__ , ## arg)

#define INFO(format, arg...)                                            \
        printk(KERN_INFO "%s:%s: " format "\n" , __FILE__,  __func__ , ## arg)

#include <linux/isdn/hdlc.h>
#include "fsm.h"
#include "hisax_if.h"
#include <linux/skbuff.h>

/* ======================================================================
 * FIFO handling
 */

/* Generic FIFO structure */
struct fifo {
        u_char r, w, count, size;
        spinlock_t lock;
};

/*
 * Init an FIFO
 */
static inline void fifo_init(struct fifo *fifo, int size)
{
        fifo->r = fifo->w = fifo->count = 0;
        fifo->size = size;
        spin_lock_init(&fifo->lock);
}

/*
 * Add an entry to the FIFO
 */
static inline int fifo_add(struct fifo *fifo)
{
        unsigned long flags;
        int index;

        if (!fifo) {
                return -1;
        }

        spin_lock_irqsave(&fifo->lock, flags);
        if (fifo->count == fifo->size) {
                // FIFO full
                index = -1;
        } else {
                // Return index where to get the next data to add to the FIFO
                index = fifo->w++ & (fifo->size - 1);
                fifo->count++;
        }
        spin_unlock_irqrestore(&fifo->lock, flags);
        return index;
}

/*
 * Remove an entry from the FIFO with the index returned.
 */
static inline int fifo_remove(struct fifo *fifo)
{
        unsigned long flags;
        int index;

        if (!fifo) {
                return -1;
        }

        spin_lock_irqsave(&fifo->lock, flags);
        if (!fifo->count) {
                // FIFO empty
                index = -1;
        } else {
                // Return index where to get the next data from the FIFO
                index = fifo->r++ & (fifo->size - 1);
                fifo->count--;
        }
        spin_unlock_irqrestore(&fifo->lock, flags);

        return index;
}

/* ======================================================================
 * control pipe
 */
typedef void (*ctrl_complete_t)(void *);

typedef struct ctrl_msg {
        struct usb_ctrlrequest dr;
        ctrl_complete_t complete;
        void *context;
} ctrl_msg;

/* FIFO of ctrl messages waiting to be sent */
#define MAX_EP0_MSG 16
struct ctrl_msg_fifo {
        struct fifo f;
        struct ctrl_msg data[MAX_EP0_MSG];
};

#define MAX_DFRAME_LEN_L1       300
#define HSCX_BUFMAX     4096

struct st5481_ctrl {
        struct ctrl_msg_fifo msg_fifo;
        unsigned long busy;
        struct urb *urb;
};

struct st5481_intr {
        //      struct evt_fifo evt_fifo;
        struct urb *urb;
};

struct st5481_d_out {
        struct isdnhdlc_vars hdlc_state;
        struct urb *urb[2]; /* double buffering */
        unsigned long busy;
        struct sk_buff *tx_skb;
        struct FsmInst fsm;
};

struct st5481_b_out {
        struct isdnhdlc_vars hdlc_state;
        struct urb *urb[2]; /* double buffering */
        u_char flow_event;
        u_long busy;
        struct sk_buff *tx_skb;
};

struct st5481_in {
        struct isdnhdlc_vars hdlc_state;
        struct urb *urb[2]; /* double buffering */
        int mode;
        int bufsize;
        unsigned int num_packets;
        unsigned int packet_size;
        unsigned char ep, counter;
        unsigned char *rcvbuf;
        struct st5481_adapter *adapter;
        struct hisax_if *hisax_if;
};

int st5481_setup_in(struct st5481_in *in);
void st5481_release_in(struct st5481_in *in);
void st5481_in_mode(struct st5481_in *in, int mode);

struct st5481_bcs {
        struct hisax_b_if b_if;
        struct st5481_adapter *adapter;
        struct st5481_in b_in;
        struct st5481_b_out b_out;
        int channel;
        int mode;
};

struct st5481_adapter {
        int number_of_leds;
        struct usb_device *usb_dev;
        struct hisax_d_if hisax_d_if;

        struct st5481_ctrl ctrl;
        struct st5481_intr intr;
        struct st5481_in d_in;
        struct st5481_d_out d_out;

        unsigned char leds;
        unsigned int led_counter;

        unsigned long event;

        struct FsmInst l1m;
        struct FsmTimer timer;

        struct st5481_bcs bcs[2];
};

#define TIMER3_VALUE 7000

/* ======================================================================
 *
 */

/*
 * Submit an URB with error reporting. This is a macro so
 * the __func__ returns the caller function name.
 */
#define SUBMIT_URB(urb, mem_flags)                                      \
        ({                                                              \
                int status;                                             \
                if ((status = usb_submit_urb(urb, mem_flags)) < 0) {    \
                        WARNING("usb_submit_urb failed,status=%d", status); \
                }                                                       \
                status;                                                 \
        })

/*
 * USB double buffering, return the URB index (0 or 1).
 */
static inline int get_buf_nr(struct urb *urbs[], struct urb *urb)
{
        return (urbs[0] == urb ? 0 : 1);
}

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

/* B Channel */

int  st5481_setup_b(struct st5481_bcs *bcs);
void st5481_release_b(struct st5481_bcs *bcs);
void st5481_d_l2l1(struct hisax_if *hisax_d_if, int pr, void *arg);

/* D Channel */

int  st5481_setup_d(struct st5481_adapter *adapter);
void st5481_release_d(struct st5481_adapter *adapter);
void st5481_b_l2l1(struct hisax_if *b_if, int pr, void *arg);
int  st5481_d_init(void);
void st5481_d_exit(void);

/* USB */
void st5481_ph_command(struct st5481_adapter *adapter, unsigned int command);
int st5481_setup_isocpipes(struct urb *urb[2], struct usb_device *dev,
                           unsigned int pipe, int num_packets,
                           int packet_size, int buf_size,
                           usb_complete_t complete, void *context);
void st5481_release_isocpipes(struct urb *urb[2]);

void st5481_usb_pipe_reset(struct st5481_adapter *adapter,
                           u_char pipe, ctrl_complete_t complete, void *context);
void st5481_usb_device_ctrl_msg(struct st5481_adapter *adapter,
                                u8 request, u16 value,
                                ctrl_complete_t complete, void *context);
int  st5481_setup_usb(struct st5481_adapter *adapter);
void st5481_release_usb(struct st5481_adapter *adapter);
void st5481_start(struct st5481_adapter *adapter);
void st5481_stop(struct st5481_adapter *adapter);

// ----------------------------------------------------------------------
// debugging macros

#define __debug_variable st5481_debug
#include "hisax_debug.h"

extern int st5481_debug;

#ifdef CONFIG_HISAX_DEBUG

#define DBG_ISO_PACKET(level, urb)                                      \
        if (level & __debug_variable) dump_iso_packet(__func__, urb)

static void __attribute__((unused))
dump_iso_packet(const char *name, struct urb *urb)
{
        int i, j;
        int len, ofs;
        u_char *data;

        printk(KERN_DEBUG "%s: packets=%d,errors=%d\n",
               name, urb->number_of_packets, urb->error_count);
        for (i = 0; i  < urb->number_of_packets; ++i) {
                if (urb->pipe & USB_DIR_IN) {
                        len = urb->iso_frame_desc[i].actual_length;
                } else {
                        len = urb->iso_frame_desc[i].length;
                }
                ofs = urb->iso_frame_desc[i].offset;
                printk(KERN_DEBUG "len=%.2d,ofs=%.3d ", len, ofs);
                if (len) {
                        data = urb->transfer_buffer + ofs;
                        for (j = 0; j < len; j++) {
                                printk("%.2x", data[j]);
                        }
                }
                printk("\n");
        }
}

static inline const char *ST5481_CMD_string(int evt)
{
        static char s[16];

        switch (evt) {
        case ST5481_CMD_DR: return "DR";
        case ST5481_CMD_RES: return "RES";
        case ST5481_CMD_TM1: return "TM1";
        case ST5481_CMD_TM2: return "TM2";
        case ST5481_CMD_PUP: return "PUP";
        case ST5481_CMD_AR8: return "AR8";
        case ST5481_CMD_AR10: return "AR10";
        case ST5481_CMD_ARL: return "ARL";
        case ST5481_CMD_PDN: return "PDN";
        };

        sprintf(s, "0x%x", evt);
        return s;
}

#else

#define DBG_ISO_PACKET(level, urb) do {} while (0)

#endif



#endif