[mirror_ubuntu-bionic-kernel.git] / drivers / usb / serial / cyberjack.c

/*
 *  REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver
 *
 *  Copyright (C) 2001  REINER SCT
 *  Author: Matthias Bruestle
 *
 *  Contact: support@reiner-sct.com (see MAINTAINERS)
 *
 *  This program is largely derived from work by the linux-usb group
 *  and associated source files.  Please see the usb/serial files for
 *  individual credits and copyrights.
 *
 *  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.
 *
 *  Thanks to Greg Kroah-Hartman (greg@kroah.com) for his help and
 *  patience.
 *
 *  In case of problems, please write to the contact e-mail address
 *  mentioned above.
 *
 *  Please note that later models of the cyberjack reader family are
 *  supported by a libusb-based userspace device driver.
 *
 *  Homepage: http://www.reiner-sct.de/support/treiber_cyberjack.php#linux
 */


#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include "usb-serial.h"

#define CYBERJACK_LOCAL_BUF_SIZE 32

static int debug;

/*
 * Version Information
 */
#define DRIVER_VERSION "v1.01"
#define DRIVER_AUTHOR "Matthias Bruestle"
#define DRIVER_DESC "REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver"


#define CYBERJACK_VENDOR_ID     0x0C4B
#define CYBERJACK_PRODUCT_ID    0x0100

/* Function prototypes */
static int cyberjack_startup (struct usb_serial *serial);
static void cyberjack_shutdown (struct usb_serial *serial);
static int  cyberjack_open (struct usb_serial_port *port, struct file *filp);
static void cyberjack_close (struct usb_serial_port *port, struct file *filp);
static int cyberjack_write (struct usb_serial_port *port, const unsigned char *buf, int count);
static int cyberjack_write_room( struct usb_serial_port *port );
static void cyberjack_read_int_callback (struct urb *urb, struct pt_regs *regs);
static void cyberjack_read_bulk_callback (struct urb *urb, struct pt_regs *regs);
static void cyberjack_write_bulk_callback (struct urb *urb, struct pt_regs *regs);

static struct usb_device_id id_table [] = {
        { USB_DEVICE(CYBERJACK_VENDOR_ID, CYBERJACK_PRODUCT_ID) },
        { }                     /* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, id_table);

static struct usb_driver cyberjack_driver = {
        .owner =        THIS_MODULE,
        .name =         "cyberjack",
        .probe =        usb_serial_probe,
        .disconnect =   usb_serial_disconnect,
        .id_table =     id_table,
};

static struct usb_serial_device_type cyberjack_device = {
        .owner =                THIS_MODULE,
        .name =                 "Reiner SCT Cyberjack USB card reader",
        .short_name =           "cyberjack",
        .id_table =             id_table,
        .num_interrupt_in =     1,
        .num_bulk_in =          1,
        .num_bulk_out =         1,
        .num_ports =            1,
        .attach =               cyberjack_startup,
        .shutdown =             cyberjack_shutdown,
        .open =                 cyberjack_open,
        .close =                cyberjack_close,
        .write =                cyberjack_write,
        .write_room =   cyberjack_write_room,
        .read_int_callback =    cyberjack_read_int_callback,
        .read_bulk_callback =   cyberjack_read_bulk_callback,
        .write_bulk_callback =  cyberjack_write_bulk_callback,
};

struct cyberjack_private {
        spinlock_t      lock;           /* Lock for SMP */
        short           rdtodo;         /* Bytes still to read */
        unsigned char   wrbuf[5*64];    /* Buffer for collecting data to write */
        short           wrfilled;       /* Overall data size we already got */
        short           wrsent;         /* Data already sent */
};

/* do some startup allocations not currently performed by usb_serial_probe() */
static int cyberjack_startup (struct usb_serial *serial)
{
        struct cyberjack_private *priv;
        int i;

        dbg("%s", __FUNCTION__);

        /* allocate the private data structure */
        priv = kmalloc(sizeof(struct cyberjack_private), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        /* set initial values */
        spin_lock_init(&priv->lock);
        priv->rdtodo = 0;
        priv->wrfilled = 0;
        priv->wrsent = 0;
        usb_set_serial_port_data(serial->port[0], priv);

        init_waitqueue_head(&serial->port[0]->write_wait);

        for (i = 0; i < serial->num_ports; ++i) {
                int result;
                serial->port[i]->interrupt_in_urb->dev = serial->dev;
                result = usb_submit_urb(serial->port[i]->interrupt_in_urb, 
                                        GFP_KERNEL);
                if (result)
                        err(" usb_submit_urb(read int) failed");
                dbg("%s - usb_submit_urb(int urb)", __FUNCTION__);
        }

        return( 0 );
}

static void cyberjack_shutdown (struct usb_serial *serial)
{
        int i;
        
        dbg("%s", __FUNCTION__);

        for (i=0; i < serial->num_ports; ++i) {
                usb_kill_urb(serial->port[i]->interrupt_in_urb);
                /* My special items, the standard routines free my urbs */
                kfree(usb_get_serial_port_data(serial->port[i]));
                usb_set_serial_port_data(serial->port[i], NULL);
        }
}
        
static int  cyberjack_open (struct usb_serial_port *port, struct file *filp)
{
        struct cyberjack_private *priv;
        unsigned long flags;
        int result = 0;

        dbg("%s - port %d", __FUNCTION__, port->number);

        dbg("%s - usb_clear_halt", __FUNCTION__ );
        usb_clear_halt(port->serial->dev, port->write_urb->pipe);

        /* force low_latency on so that our tty_push actually forces
         * the data through, otherwise it is scheduled, and with high
         * data rates (like with OHCI) data can get lost.
         */
        port->tty->low_latency = 1;

        priv = usb_get_serial_port_data(port);
        spin_lock_irqsave(&priv->lock, flags);
        priv->rdtodo = 0;
        priv->wrfilled = 0;
        priv->wrsent = 0;
        spin_unlock_irqrestore(&priv->lock, flags);

        return result;
}

static void cyberjack_close (struct usb_serial_port *port, struct file *filp)
{
        dbg("%s - port %d", __FUNCTION__, port->number);

        if (port->serial->dev) {
                /* shutdown any bulk reads that might be going on */
                usb_kill_urb(port->write_urb);
                usb_kill_urb(port->read_urb);
        }
}

static int cyberjack_write (struct usb_serial_port *port, const unsigned char *buf, int count)
{
        struct usb_serial *serial = port->serial;
        struct cyberjack_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        int result;
        int wrexpected;

        dbg("%s - port %d", __FUNCTION__, port->number);

        if (count == 0) {
                dbg("%s - write request of 0 bytes", __FUNCTION__);
                return (0);
        }

        spin_lock(&port->lock);
        if (port->write_urb_busy) {
                spin_unlock(&port->lock);
                dbg("%s - already writing", __FUNCTION__);
                return 0;
        }
        port->write_urb_busy = 1;
        spin_unlock(&port->lock);

        spin_lock_irqsave(&priv->lock, flags);

        if( (count+priv->wrfilled)>sizeof(priv->wrbuf) ) {
                /* To much data for buffer. Reset buffer. */
                priv->wrfilled=0;
                spin_unlock_irqrestore(&priv->lock, flags);
                port->write_urb_busy = 0;
                return (0);
        }

        /* Copy data */
        memcpy (priv->wrbuf+priv->wrfilled, buf, count);

        usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count,
                priv->wrbuf+priv->wrfilled);
        priv->wrfilled += count;

        if( priv->wrfilled >= 3 ) {
                wrexpected = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
                dbg("%s - expected data: %d", __FUNCTION__, wrexpected);
        } else {
                wrexpected = sizeof(priv->wrbuf);
        }

        if( priv->wrfilled >= wrexpected ) {
                /* We have enough data to begin transmission */
                int length;

                dbg("%s - transmitting data (frame 1)", __FUNCTION__);
                length = (wrexpected > port->bulk_out_size) ? port->bulk_out_size : wrexpected;

                memcpy (port->write_urb->transfer_buffer, priv->wrbuf, length );
                priv->wrsent=length;

                /* set up our urb */
                usb_fill_bulk_urb(port->write_urb, serial->dev, 
                              usb_sndbulkpipe(serial->dev, port->bulk_out_endpointAddress),
                              port->write_urb->transfer_buffer, length,
                              ((serial->type->write_bulk_callback) ? 
                               serial->type->write_bulk_callback : 
                               cyberjack_write_bulk_callback), 
                              port);

                /* send the data out the bulk port */
                result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
                if (result) {
                        err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
                        /* Throw away data. No better idea what to do with it. */
                        priv->wrfilled=0;
                        priv->wrsent=0;
                        spin_unlock_irqrestore(&priv->lock, flags);
                        port->write_urb_busy = 0;
                        return 0;
                }

                dbg("%s - priv->wrsent=%d", __FUNCTION__,priv->wrsent);
                dbg("%s - priv->wrfilled=%d", __FUNCTION__,priv->wrfilled);

                if( priv->wrsent>=priv->wrfilled ) {
                        dbg("%s - buffer cleaned", __FUNCTION__);
                        memset( priv->wrbuf, 0, sizeof(priv->wrbuf) );
                        priv->wrfilled=0;
                        priv->wrsent=0;
                }
        }

        spin_unlock_irqrestore(&priv->lock, flags);

        return (count);
} 

static int cyberjack_write_room( struct usb_serial_port *port )
{
        return CYBERJACK_LOCAL_BUF_SIZE;
}

static void cyberjack_read_int_callback( struct urb *urb, struct pt_regs *regs )
{
        struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
        struct cyberjack_private *priv = usb_get_serial_port_data(port);
        unsigned char *data = urb->transfer_buffer;
        int result;

        dbg("%s - port %d", __FUNCTION__, port->number);

        /* the urb might have been killed. */
        if (urb->status)
                return;

        usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);

        /* React only to interrupts signaling a bulk_in transfer */
        if( (urb->actual_length==4) && (data[0]==0x01) ) {
                short old_rdtodo;
                int result;

                /* This is a announcement of coming bulk_ins. */
                unsigned short size = ((unsigned short)data[3]<<8)+data[2]+3;

                spin_lock(&priv->lock);

                old_rdtodo = priv->rdtodo;

                if( (old_rdtodo+size)<(old_rdtodo) ) {
                        dbg( "To many bulk_in urbs to do." );
                        spin_unlock(&priv->lock);
                        goto resubmit;
                }

                /* "+=" is probably more fault tollerant than "=" */
                priv->rdtodo += size;

                dbg("%s - rdtodo: %d", __FUNCTION__, priv->rdtodo);

                spin_unlock(&priv->lock);

                if( !old_rdtodo ) {
                        port->read_urb->dev = port->serial->dev;
                        result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
                        if( result )
                                err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
                        dbg("%s - usb_submit_urb(read urb)", __FUNCTION__);
                }
        }

resubmit:
        port->interrupt_in_urb->dev = port->serial->dev;
        result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
        if (result)
                err(" usb_submit_urb(read int) failed");
        dbg("%s - usb_submit_urb(int urb)", __FUNCTION__);
}

static void cyberjack_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
{
        struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
        struct cyberjack_private *priv = usb_get_serial_port_data(port);
        struct tty_struct *tty;
        unsigned char *data = urb->transfer_buffer;
        short todo;
        int i;
        int result;

        dbg("%s - port %d", __FUNCTION__, port->number);
        
        usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
        if (urb->status) {
                dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
                return;
        }

        tty = port->tty;
        if (!tty) {
                dbg("%s - ignoring since device not open\n", __FUNCTION__);
                return;
        }
        if (urb->actual_length) {
                for (i = 0; i < urb->actual_length ; ++i) {
                        /* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
                        if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
                                tty_flip_buffer_push(tty);
                        }
                        /* this doesn't actually push the data through unless tty->low_latency is set */
                        tty_insert_flip_char(tty, data[i], 0);
                }
                tty_flip_buffer_push(tty);
        }

        spin_lock(&priv->lock);

        /* Reduce urbs to do by one. */
        priv->rdtodo-=urb->actual_length;
        /* Just to be sure */
        if ( priv->rdtodo<0 ) priv->rdtodo = 0;
        todo = priv->rdtodo;

        spin_unlock(&priv->lock);

        dbg("%s - rdtodo: %d", __FUNCTION__, todo);

        /* Continue to read if we have still urbs to do. */
        if( todo /* || (urb->actual_length==port->bulk_in_endpointAddress)*/ ) {
                port->read_urb->dev = port->serial->dev;
                result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
                if (result)
                        err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
                dbg("%s - usb_submit_urb(read urb)", __FUNCTION__);
        }
}

static void cyberjack_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
{
        struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
        struct cyberjack_private *priv = usb_get_serial_port_data(port);

        dbg("%s - port %d", __FUNCTION__, port->number);

        port->write_urb_busy = 0;
        if (urb->status) {
                dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
                return;
        }

        spin_lock(&priv->lock);

        /* only do something if we have more data to send */
        if( priv->wrfilled ) {
                int length, blksize, result;

                dbg("%s - transmitting data (frame n)", __FUNCTION__);

                length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?
                        port->bulk_out_size : (priv->wrfilled - priv->wrsent);

                memcpy (port->write_urb->transfer_buffer, priv->wrbuf + priv->wrsent,
                        length );
                priv->wrsent+=length;

                /* set up our urb */
                usb_fill_bulk_urb(port->write_urb, port->serial->dev, 
                              usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
                              port->write_urb->transfer_buffer, length,
                              ((port->serial->type->write_bulk_callback) ? 
                               port->serial->type->write_bulk_callback : 
                               cyberjack_write_bulk_callback), 
                              port);

                /* send the data out the bulk port */
                result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
                if (result) {
                        err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
                        /* Throw away data. No better idea what to do with it. */
                        priv->wrfilled=0;
                        priv->wrsent=0;
                        goto exit;
                }

                dbg("%s - priv->wrsent=%d", __FUNCTION__,priv->wrsent);
                dbg("%s - priv->wrfilled=%d", __FUNCTION__,priv->wrfilled);

                blksize = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;

                if( (priv->wrsent>=priv->wrfilled) || (priv->wrsent>=blksize) ) {
                        dbg("%s - buffer cleaned", __FUNCTION__);
                        memset( priv->wrbuf, 0, sizeof(priv->wrbuf) );
                        priv->wrfilled=0;
                        priv->wrsent=0;
                }
        }

exit:
        spin_unlock(&priv->lock);
        schedule_work(&port->work);
}

static int __init cyberjack_init (void)
{
        int retval;
        retval  = usb_serial_register(&cyberjack_device);
        if (retval)
                goto failed_usb_serial_register;
        retval = usb_register(&cyberjack_driver);
        if (retval) 
                goto failed_usb_register;

        info(DRIVER_VERSION " " DRIVER_AUTHOR);
        info(DRIVER_DESC);

        return 0;
failed_usb_register:
        usb_serial_deregister(&cyberjack_device);
failed_usb_serial_register:
        return retval;
}

static void __exit cyberjack_exit (void)
{
        usb_deregister (&cyberjack_driver);
        usb_serial_deregister (&cyberjack_device);
}

module_init(cyberjack_init);
module_exit(cyberjack_exit);

MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_VERSION( DRIVER_VERSION );
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");