drivers/usb/serial/kobil_sct.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  *  KOBIL USB Smart Card Terminal Driver
  *
  *  Copyright (C) 2002  KOBIL Systems GmbH
  *  Author: Thomas Wahrenbruch
  *
  *  Contact: linuxusb@kobil.de
  *
  *  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.
  *
  *  Thanks to Greg Kroah-Hartman (greg@kroah.com) for his help and
  *  patience.
  *
  * Supported readers: USB TWIN, KAAN Standard Plus and SecOVID Reader Plus
  * (Adapter K), B1 Professional and KAAN Professional (Adapter B)
  */


 #include <linux/kernel.h>
 #include <linux/errno.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 <linux/uaccess.h>
 #include <linux/usb.h>
 #include <linux/usb/serial.h>
 #include <linux/ioctl.h>
 #include "kobil_sct.h"

 #define DRIVER_AUTHOR "KOBIL Systems GmbH - http://www.kobil.com"
 #define DRIVER_DESC "KOBIL USB Smart Card Terminal Driver (experimental)"

 #define KOBIL_VENDOR_ID			0x0D46
 #define KOBIL_ADAPTER_B_PRODUCT_ID	0x2011
 #define KOBIL_ADAPTER_K_PRODUCT_ID	0x2012
 #define KOBIL_USBTWIN_PRODUCT_ID	0x0078
 #define KOBIL_KAAN_SIM_PRODUCT_ID       0x0081

 #define KOBIL_TIMEOUT		500
 #define KOBIL_BUF_LENGTH	300


 /* Function prototypes */
 static int kobil_port_probe(struct usb_serial_port *probe);
 static void kobil_port_remove(struct usb_serial_port *probe);
 static int  kobil_open(struct tty_struct *tty, struct usb_serial_port *port);
 static void kobil_close(struct usb_serial_port *port);
 static int  kobil_write(struct tty_struct *tty, struct usb_serial_port *port,
 			 const unsigned char *buf, int count);
 static int  kobil_write_room(struct tty_struct *tty);
 static int  kobil_ioctl(struct tty_struct *tty,
 			unsigned int cmd, unsigned long arg);
 static int  kobil_tiocmget(struct tty_struct *tty);
 static int  kobil_tiocmset(struct tty_struct *tty,
 			   unsigned int set, unsigned int clear);
 static void kobil_read_int_callback(struct urb *urb);
 static void kobil_write_int_callback(struct urb *urb);
 static void kobil_set_termios(struct tty_struct *tty,
 			struct usb_serial_port *port, struct ktermios *old);
 static void kobil_init_termios(struct tty_struct *tty);

 static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_ADAPTER_B_PRODUCT_ID) },
 	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_ADAPTER_K_PRODUCT_ID) },
 	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_USBTWIN_PRODUCT_ID) },
 	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_KAAN_SIM_PRODUCT_ID) },
 	{ }			/* Terminating entry */
 };
 MODULE_DEVICE_TABLE(usb, id_table);

 static struct usb_serial_driver kobil_device = {
 	.driver = {
 		.owner =	THIS_MODULE,
 		.name =		"kobil",
 	},
 	.description =		"KOBIL USB smart card terminal",
 	.id_table =		id_table,
 	.num_ports =		1,
 	.num_interrupt_out =	1,
 	.port_probe =		kobil_port_probe,
 	.port_remove =		kobil_port_remove,
 	.ioctl =		kobil_ioctl,
 	.set_termios =		kobil_set_termios,
 	.init_termios =		kobil_init_termios,
 	.tiocmget =		kobil_tiocmget,
 	.tiocmset =		kobil_tiocmset,
 	.open =			kobil_open,
 	.close =		kobil_close,
 	.write =		kobil_write,
 	.write_room =		kobil_write_room,
 	.read_int_callback =	kobil_read_int_callback,
 	.write_int_callback =	kobil_write_int_callback,
 };

 static struct usb_serial_driver * const serial_drivers[] = {
 	&kobil_device, NULL
 };

 struct kobil_private {
 	unsigned char buf[KOBIL_BUF_LENGTH]; /* buffer for the APDU to send */
 	int filled;  /* index of the last char in buf */
 	int cur_pos; /* index of the next char to send in buf */
 	__u16 device_type;
 };


 static int kobil_port_probe(struct usb_serial_port *port)
 {
 	struct usb_serial *serial = port->serial;
 	struct kobil_private *priv;

 	priv = kmalloc(sizeof(struct kobil_private), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	priv->filled = 0;
 	priv->cur_pos = 0;
 	priv->device_type = le16_to_cpu(serial->dev->descriptor.idProduct);

 	switch (priv->device_type) {
 	case KOBIL_ADAPTER_B_PRODUCT_ID:
 		dev_dbg(&serial->dev->dev, "KOBIL B1 PRO / KAAN PRO detected\n");
 		break;
 	case KOBIL_ADAPTER_K_PRODUCT_ID:
 		dev_dbg(&serial->dev->dev, "KOBIL KAAN Standard Plus / SecOVID Reader Plus detected\n");
 		break;
 	case KOBIL_USBTWIN_PRODUCT_ID:
 		dev_dbg(&serial->dev->dev, "KOBIL USBTWIN detected\n");
 		break;
 	case KOBIL_KAAN_SIM_PRODUCT_ID:
 		dev_dbg(&serial->dev->dev, "KOBIL KAAN SIM detected\n");
 		break;
 	}
 	usb_set_serial_port_data(port, priv);

 	return 0;
 }


 static void kobil_port_remove(struct usb_serial_port *port)
 {
 	struct kobil_private *priv;

 	priv = usb_get_serial_port_data(port);
 	kfree(priv);
 }

 static void kobil_init_termios(struct tty_struct *tty)
 {
 	/* Default to echo off and other sane device settings */
 	tty->termios.c_lflag = 0;
 	tty->termios.c_iflag &= ~(ISIG | ICANON | ECHO | IEXTEN | XCASE);
 	tty->termios.c_iflag |= IGNBRK | IGNPAR | IXOFF;
 	/* do NOT translate CR to CR-NL (0x0A -> 0x0A 0x0D) */
 	tty->termios.c_oflag &= ~ONLCR;
 }

 static int kobil_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
 	struct device *dev = &port->dev;
 	int result = 0;
 	struct kobil_private *priv;
 	unsigned char *transfer_buffer;
 	int transfer_buffer_length = 8;

 	priv = usb_get_serial_port_data(port);

 	/* allocate memory for transfer buffer */
 	transfer_buffer = kzalloc(transfer_buffer_length, GFP_KERNEL);
 	if (!transfer_buffer)
 		return -ENOMEM;

 	/* get hardware version */
 	result = usb_control_msg(port->serial->dev,
 			  usb_rcvctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_GetMisc,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_IN,
 			  SUSBCR_MSC_GetHWVersion,
 			  0,
 			  transfer_buffer,
 			  transfer_buffer_length,
 			  KOBIL_TIMEOUT
 	);
 	dev_dbg(dev, "%s - Send get_HW_version URB returns: %i\n", __func__, result);
 	if (result >= 3) {
 		dev_dbg(dev, "Hardware version: %i.%i.%i\n", transfer_buffer[0],
 				transfer_buffer[1], transfer_buffer[2]);
 	}

 	/* get firmware version */
 	result = usb_control_msg(port->serial->dev,
 			  usb_rcvctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_GetMisc,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_IN,
 			  SUSBCR_MSC_GetFWVersion,
 			  0,
 			  transfer_buffer,
 			  transfer_buffer_length,
 			  KOBIL_TIMEOUT
 	);
 	dev_dbg(dev, "%s - Send get_FW_version URB returns: %i\n", __func__, result);
 	if (result >= 3) {
 		dev_dbg(dev, "Firmware version: %i.%i.%i\n", transfer_buffer[0],
 				transfer_buffer[1], transfer_buffer[2]);
 	}

 	if (priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID ||
 			priv->device_type == KOBIL_ADAPTER_K_PRODUCT_ID) {
 		/* Setting Baudrate, Parity and Stopbits */
 		result = usb_control_msg(port->serial->dev,
 			  usb_sndctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_SetBaudRateParityAndStopBits,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 			  SUSBCR_SBR_9600 | SUSBCR_SPASB_EvenParity |
 							SUSBCR_SPASB_1StopBit,
 			  0,
 			  NULL,
 			  0,
 			  KOBIL_TIMEOUT
 		);
 		dev_dbg(dev, "%s - Send set_baudrate URB returns: %i\n", __func__, result);

 		/* reset all queues */
 		result = usb_control_msg(port->serial->dev,
 			  usb_sndctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_Misc,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 			  SUSBCR_MSC_ResetAllQueues,
 			  0,
 			  NULL,
 			  0,
 			  KOBIL_TIMEOUT
 		);
 		dev_dbg(dev, "%s - Send reset_all_queues URB returns: %i\n", __func__, result);
 	}
 	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID ||
 	    priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID ||
 	    priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
 		/* start reading (Adapter B 'cause PNP string) */
 		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 		dev_dbg(dev, "%s - Send read URB returns: %i\n", __func__, result);
 	}

 	kfree(transfer_buffer);
 	return 0;
 }


 static void kobil_close(struct usb_serial_port *port)
 {
 	/* FIXME: Add rts/dtr methods */
 	usb_kill_urb(port->interrupt_out_urb);
 	usb_kill_urb(port->interrupt_in_urb);
 }


 static void kobil_read_int_callback(struct urb *urb)
 {
 	int result;
 	struct usb_serial_port *port = urb->context;
 	unsigned char *data = urb->transfer_buffer;
 	int status = urb->status;

 	if (status) {
 		dev_dbg(&port->dev, "%s - Read int status not zero: %d\n", __func__, status);
 		return;
 	}

 	if (urb->actual_length) {
 		usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
 									data);
 		tty_insert_flip_string(&port->port, data, urb->actual_length);
 		tty_flip_buffer_push(&port->port);
 	}

 	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 	dev_dbg(&port->dev, "%s - Send read URB returns: %i\n", __func__, result);
 }


 static void kobil_write_int_callback(struct urb *urb)
 {
 }


 static int kobil_write(struct tty_struct *tty, struct usb_serial_port *port,
 			const unsigned char *buf, int count)
 {
 	int length = 0;
 	int result = 0;
 	int todo = 0;
 	struct kobil_private *priv;

 	if (count == 0) {
 		dev_dbg(&port->dev, "%s - write request of 0 bytes\n", __func__);
 		return 0;
 	}

 	priv = usb_get_serial_port_data(port);

 	if (count > (KOBIL_BUF_LENGTH - priv->filled)) {
 		dev_dbg(&port->dev, "%s - Error: write request bigger than buffer size\n", __func__);
 		return -ENOMEM;
 	}

 	/* Copy data to buffer */
 	memcpy(priv->buf + priv->filled, buf, count);
 	usb_serial_debug_data(&port->dev, __func__, count, priv->buf + priv->filled);
 	priv->filled = priv->filled + count;

 	/* only send complete block. TWIN, KAAN SIM and adapter K
 	   use the same protocol. */
 	if (((priv->device_type != KOBIL_ADAPTER_B_PRODUCT_ID) && (priv->filled > 2) && (priv->filled >= (priv->buf[1] + 3))) ||
 	     ((priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID) && (priv->filled > 3) && (priv->filled >= (priv->buf[2] + 4)))) {
 		/* stop reading (except TWIN and KAAN SIM) */
 		if ((priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID)
 			|| (priv->device_type == KOBIL_ADAPTER_K_PRODUCT_ID))
 			usb_kill_urb(port->interrupt_in_urb);

 		todo = priv->filled - priv->cur_pos;

 		while (todo > 0) {
 			/* max 8 byte in one urb (endpoint size) */
 			length = min(todo, port->interrupt_out_size);
 			/* copy data to transfer buffer */
 			memcpy(port->interrupt_out_buffer,
 					priv->buf + priv->cur_pos, length);
 			port->interrupt_out_urb->transfer_buffer_length = length;

 			priv->cur_pos = priv->cur_pos + length;
 			result = usb_submit_urb(port->interrupt_out_urb,
 					GFP_ATOMIC);
 			dev_dbg(&port->dev, "%s - Send write URB returns: %i\n", __func__, result);
 			todo = priv->filled - priv->cur_pos;

 			if (todo > 0)
 				msleep(24);
 		}

 		priv->filled = 0;
 		priv->cur_pos = 0;

 		/* start reading (except TWIN and KAAN SIM) */
 		if (priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID ||
 			priv->device_type == KOBIL_ADAPTER_K_PRODUCT_ID) {
 			result = usb_submit_urb(port->interrupt_in_urb,
 					GFP_ATOMIC);
 			dev_dbg(&port->dev, "%s - Send read URB returns: %i\n", __func__, result);
 		}
 	}
 	return count;
 }


 static int kobil_write_room(struct tty_struct *tty)
 {
 	/* FIXME */
 	return 8;
 }


 static int kobil_tiocmget(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct kobil_private *priv;
 	int result;
 	unsigned char *transfer_buffer;
 	int transfer_buffer_length = 8;

 	priv = usb_get_serial_port_data(port);
 	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID
 			|| priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
 		/* This device doesn't support ioctl calls */
 		return -EINVAL;
 	}

 	/* allocate memory for transfer buffer */
 	transfer_buffer = kzalloc(transfer_buffer_length, GFP_KERNEL);
 	if (!transfer_buffer)
 		return -ENOMEM;

 	result = usb_control_msg(port->serial->dev,
 			  usb_rcvctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_GetStatusLineState,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_IN,
 			  0,
 			  0,
 			  transfer_buffer,
 			  transfer_buffer_length,
 			  KOBIL_TIMEOUT);

 	dev_dbg(&port->dev, "Send get_status_line_state URB returns: %i\n",
 			result);
 	if (result < 1) {
 		if (result >= 0)
 			result = -EIO;
 		goto out_free;
 	}

 	dev_dbg(&port->dev, "Statusline: %02x\n", transfer_buffer[0]);

 	result = 0;
 	if ((transfer_buffer[0] & SUSBCR_GSL_DSR) != 0)
 		result = TIOCM_DSR;
 out_free:
 	kfree(transfer_buffer);
 	return result;
 }

 static int kobil_tiocmset(struct tty_struct *tty,
 			   unsigned int set, unsigned int clear)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct device *dev = &port->dev;
 	struct kobil_private *priv;
 	int result;
 	int dtr = 0;
 	int rts = 0;

 	/* FIXME: locking ? */
 	priv = usb_get_serial_port_data(port);
 	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID
 		|| priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
 		/* This device doesn't support ioctl calls */
 		return -EINVAL;
 	}

 	if (set & TIOCM_RTS)
 		rts = 1;
 	if (set & TIOCM_DTR)
 		dtr = 1;
 	if (clear & TIOCM_RTS)
 		rts = 0;
 	if (clear & TIOCM_DTR)
 		dtr = 0;

 	if (priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID) {
 		if (dtr != 0)
 			dev_dbg(dev, "%s - Setting DTR\n", __func__);
 		else
 			dev_dbg(dev, "%s - Clearing DTR\n", __func__);
 		result = usb_control_msg(port->serial->dev,
 			  usb_sndctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_SetStatusLinesOrQueues,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 			  ((dtr != 0) ? SUSBCR_SSL_SETDTR : SUSBCR_SSL_CLRDTR),
 			  0,
 			  NULL,
 			  0,
 			  KOBIL_TIMEOUT);
 	} else {
 		if (rts != 0)
 			dev_dbg(dev, "%s - Setting RTS\n", __func__);
 		else
 			dev_dbg(dev, "%s - Clearing RTS\n", __func__);
 		result = usb_control_msg(port->serial->dev,
 			usb_sndctrlpipe(port->serial->dev, 0),
 			SUSBCRequest_SetStatusLinesOrQueues,
 			USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 			((rts != 0) ? SUSBCR_SSL_SETRTS : SUSBCR_SSL_CLRRTS),
 			0,
 			NULL,
 			0,
 			KOBIL_TIMEOUT);
 	}
 	dev_dbg(dev, "%s - Send set_status_line URB returns: %i\n", __func__, result);
 	return (result < 0) ? result : 0;
 }

 static void kobil_set_termios(struct tty_struct *tty,
 			struct usb_serial_port *port, struct ktermios *old)
 {
 	struct kobil_private *priv;
 	int result;
 	unsigned short urb_val = 0;
 	int c_cflag = tty->termios.c_cflag;
 	speed_t speed;

 	priv = usb_get_serial_port_data(port);
 	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID ||
 			priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
 		/* This device doesn't support ioctl calls */
 		tty_termios_copy_hw(&tty->termios, old);
 		return;
 	}

 	speed = tty_get_baud_rate(tty);
 	switch (speed) {
 	case 1200:
 		urb_val = SUSBCR_SBR_1200;
 		break;
 	default:
 		speed = 9600;
 		fallthrough;
 	case 9600:
 		urb_val = SUSBCR_SBR_9600;
 		break;
 	}
 	urb_val |= (c_cflag & CSTOPB) ? SUSBCR_SPASB_2StopBits :
 							SUSBCR_SPASB_1StopBit;
 	if (c_cflag & PARENB) {
 		if  (c_cflag & PARODD)
 			urb_val |= SUSBCR_SPASB_OddParity;
 		else
 			urb_val |= SUSBCR_SPASB_EvenParity;
 	} else
 		urb_val |= SUSBCR_SPASB_NoParity;
 	tty->termios.c_cflag &= ~CMSPAR;
 	tty_encode_baud_rate(tty, speed, speed);

 	result = usb_control_msg(port->serial->dev,
 		  usb_sndctrlpipe(port->serial->dev, 0),
 		  SUSBCRequest_SetBaudRateParityAndStopBits,
 		  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 		  urb_val,
 		  0,
 		  NULL,
 		  0,
 		  KOBIL_TIMEOUT
 		);
 	if (result) {
 		dev_err(&port->dev, "failed to update line settings: %d\n",
 				result);
 	}
 }

 static int kobil_ioctl(struct tty_struct *tty,
 					unsigned int cmd, unsigned long arg)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct kobil_private *priv = usb_get_serial_port_data(port);
 	int result;

 	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID ||
 			priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID)
 		/* This device doesn't support ioctl calls */
 		return -ENOIOCTLCMD;

 	switch (cmd) {
 	case TCFLSH:
 		result = usb_control_msg(port->serial->dev,
 			  usb_sndctrlpipe(port->serial->dev, 0),
 			  SUSBCRequest_Misc,
 			  USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 			  SUSBCR_MSC_ResetAllQueues,
 			  0,
 			  NULL,
 			  0,
 			  KOBIL_TIMEOUT
 			);

 		dev_dbg(&port->dev,
 			"%s - Send reset_all_queues (FLUSH) URB returns: %i\n",
 			__func__, result);
 		return (result < 0) ? -EIO: 0;
 	default:
 		return -ENOIOCTLCMD;
 	}
 }

 module_usb_serial_driver(serial_drivers, id_table);

 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* KOBIL USB Smart Card Terminal Driver
	*
	* Copyright (C) 2002 KOBIL Systems GmbH
	* Author: Thomas Wahrenbruch
	*
	* Contact: linuxusb@kobil.de
	*
	* 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.
	*
	* Thanks to Greg Kroah-Hartman (greg@kroah.com) for his help and
	* patience.
	*
	* Supported readers: USB TWIN, KAAN Standard Plus and SecOVID Reader Plus
	* (Adapter K), B1 Professional and KAAN Professional (Adapter B)
	*/


	#include <linux/kernel.h>
	#include <linux/errno.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 <linux/uaccess.h>
	#include <linux/usb.h>
	#include <linux/usb/serial.h>
	#include <linux/ioctl.h>
	#include "kobil_sct.h"

	#define DRIVER_AUTHOR "KOBIL Systems GmbH - http://www.kobil.com"
	#define DRIVER_DESC "KOBIL USB Smart Card Terminal Driver (experimental)"

	#define KOBIL_VENDOR_ID 0x0D46
	#define KOBIL_ADAPTER_B_PRODUCT_ID 0x2011
	#define KOBIL_ADAPTER_K_PRODUCT_ID 0x2012
	#define KOBIL_USBTWIN_PRODUCT_ID 0x0078
	#define KOBIL_KAAN_SIM_PRODUCT_ID 0x0081

	#define KOBIL_TIMEOUT 500
	#define KOBIL_BUF_LENGTH 300


	/* Function prototypes */
	static int kobil_port_probe(struct usb_serial_port *probe);
	static void kobil_port_remove(struct usb_serial_port *probe);
	static int kobil_open(struct tty_struct tty, struct usb_serial_port port);
	static void kobil_close(struct usb_serial_port *port);
	static int kobil_write(struct tty_struct tty, struct usb_serial_port port,
	const unsigned char *buf, int count);
	static int kobil_write_room(struct tty_struct *tty);
	static int kobil_ioctl(struct tty_struct *tty,
	unsigned int cmd, unsigned long arg);
	static int kobil_tiocmget(struct tty_struct *tty);
	static int kobil_tiocmset(struct tty_struct *tty,
	unsigned int set, unsigned int clear);
	static void kobil_read_int_callback(struct urb *urb);
	static void kobil_write_int_callback(struct urb *urb);
	static void kobil_set_termios(struct tty_struct *tty,
	struct usb_serial_port port, struct ktermios old);
	static void kobil_init_termios(struct tty_struct *tty);

	static const struct usb_device_id id_table[] = {
	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_ADAPTER_B_PRODUCT_ID) },
	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_ADAPTER_K_PRODUCT_ID) },
	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_USBTWIN_PRODUCT_ID) },
	{ USB_DEVICE(KOBIL_VENDOR_ID, KOBIL_KAAN_SIM_PRODUCT_ID) },
	{ } /* Terminating entry */
	};
	MODULE_DEVICE_TABLE(usb, id_table);

	static struct usb_serial_driver kobil_device = {
	.driver = {
	.owner = THIS_MODULE,
	.name = "kobil",
	},
	.description = "KOBIL USB smart card terminal",
	.id_table = id_table,
	.num_ports = 1,
	.num_interrupt_out = 1,
	.port_probe = kobil_port_probe,
	.port_remove = kobil_port_remove,
	.ioctl = kobil_ioctl,
	.set_termios = kobil_set_termios,
	.init_termios = kobil_init_termios,
	.tiocmget = kobil_tiocmget,
	.tiocmset = kobil_tiocmset,
	.open = kobil_open,
	.close = kobil_close,
	.write = kobil_write,
	.write_room = kobil_write_room,
	.read_int_callback = kobil_read_int_callback,
	.write_int_callback = kobil_write_int_callback,
	};

	static struct usb_serial_driver * const serial_drivers[] = {
	&kobil_device, NULL
	};

	struct kobil_private {
	unsigned char buf[KOBIL_BUF_LENGTH]; /* buffer for the APDU to send */
	int filled; /* index of the last char in buf */
	int cur_pos; /* index of the next char to send in buf */
	__u16 device_type;
	};


	static int kobil_port_probe(struct usb_serial_port *port)
	{
	struct usb_serial *serial = port->serial;
	struct kobil_private *priv;

	priv = kmalloc(sizeof(struct kobil_private), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	priv->filled = 0;
	priv->cur_pos = 0;
	priv->device_type = le16_to_cpu(serial->dev->descriptor.idProduct);

	switch (priv->device_type) {
	case KOBIL_ADAPTER_B_PRODUCT_ID:
	dev_dbg(&serial->dev->dev, "KOBIL B1 PRO / KAAN PRO detected\n");
	break;
	case KOBIL_ADAPTER_K_PRODUCT_ID:
	dev_dbg(&serial->dev->dev, "KOBIL KAAN Standard Plus / SecOVID Reader Plus detected\n");
	break;
	case KOBIL_USBTWIN_PRODUCT_ID:
	dev_dbg(&serial->dev->dev, "KOBIL USBTWIN detected\n");
	break;
	case KOBIL_KAAN_SIM_PRODUCT_ID:
	dev_dbg(&serial->dev->dev, "KOBIL KAAN SIM detected\n");
	break;
	}
	usb_set_serial_port_data(port, priv);

	return 0;
	}


	static void kobil_port_remove(struct usb_serial_port *port)
	{
	struct kobil_private *priv;

	priv = usb_get_serial_port_data(port);
	kfree(priv);
	}

	static void kobil_init_termios(struct tty_struct *tty)
	{
	/* Default to echo off and other sane device settings */
	tty->termios.c_lflag = 0;
	tty->termios.c_iflag &= ~(ISIG \| ICANON \| ECHO \| IEXTEN \| XCASE);
	tty->termios.c_iflag \|= IGNBRK \| IGNPAR \| IXOFF;
	/* do NOT translate CR to CR-NL (0x0A -> 0x0A 0x0D) */
	tty->termios.c_oflag &= ~ONLCR;
	}

	static int kobil_open(struct tty_struct tty, struct usb_serial_port port)
	{
	struct device *dev = &port->dev;
	int result = 0;
	struct kobil_private *priv;
	unsigned char *transfer_buffer;
	int transfer_buffer_length = 8;

	priv = usb_get_serial_port_data(port);

	/* allocate memory for transfer buffer */
	transfer_buffer = kzalloc(transfer_buffer_length, GFP_KERNEL);
	if (!transfer_buffer)
	return -ENOMEM;

	/* get hardware version */
	result = usb_control_msg(port->serial->dev,
	usb_rcvctrlpipe(port->serial->dev, 0),
	SUSBCRequest_GetMisc,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_IN,
	SUSBCR_MSC_GetHWVersion,
	0,
	transfer_buffer,
	transfer_buffer_length,
	KOBIL_TIMEOUT
	);
	dev_dbg(dev, "%s - Send get_HW_version URB returns: %i\n", __func__, result);
	if (result >= 3) {
	dev_dbg(dev, "Hardware version: %i.%i.%i\n", transfer_buffer[0],
	transfer_buffer[1], transfer_buffer[2]);
	}

	/* get firmware version */
	result = usb_control_msg(port->serial->dev,
	usb_rcvctrlpipe(port->serial->dev, 0),
	SUSBCRequest_GetMisc,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_IN,
	SUSBCR_MSC_GetFWVersion,
	0,
	transfer_buffer,
	transfer_buffer_length,
	KOBIL_TIMEOUT
	);
	dev_dbg(dev, "%s - Send get_FW_version URB returns: %i\n", __func__, result);
	if (result >= 3) {
	dev_dbg(dev, "Firmware version: %i.%i.%i\n", transfer_buffer[0],
	transfer_buffer[1], transfer_buffer[2]);
	}

	if (priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID \|\|
	priv->device_type == KOBIL_ADAPTER_K_PRODUCT_ID) {
	/* Setting Baudrate, Parity and Stopbits */
	result = usb_control_msg(port->serial->dev,
	usb_sndctrlpipe(port->serial->dev, 0),
	SUSBCRequest_SetBaudRateParityAndStopBits,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	SUSBCR_SBR_9600 \| SUSBCR_SPASB_EvenParity \|
	SUSBCR_SPASB_1StopBit,
	0,
	NULL,
	0,
	KOBIL_TIMEOUT
	);
	dev_dbg(dev, "%s - Send set_baudrate URB returns: %i\n", __func__, result);

	/* reset all queues */
	result = usb_control_msg(port->serial->dev,
	usb_sndctrlpipe(port->serial->dev, 0),
	SUSBCRequest_Misc,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	SUSBCR_MSC_ResetAllQueues,
	0,
	NULL,
	0,
	KOBIL_TIMEOUT
	);
	dev_dbg(dev, "%s - Send reset_all_queues URB returns: %i\n", __func__, result);
	}
	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID \|\|
	priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID \|\|
	priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
	/* start reading (Adapter B 'cause PNP string) */
	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
	dev_dbg(dev, "%s - Send read URB returns: %i\n", __func__, result);
	}

	kfree(transfer_buffer);
	return 0;
	}


	static void kobil_close(struct usb_serial_port *port)
	{
	/* FIXME: Add rts/dtr methods */
	usb_kill_urb(port->interrupt_out_urb);
	usb_kill_urb(port->interrupt_in_urb);
	}


	static void kobil_read_int_callback(struct urb *urb)
	{
	int result;
	struct usb_serial_port *port = urb->context;
	unsigned char *data = urb->transfer_buffer;
	int status = urb->status;

	if (status) {
	dev_dbg(&port->dev, "%s - Read int status not zero: %d\n", __func__, status);
	return;
	}

	if (urb->actual_length) {
	usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
	data);
	tty_insert_flip_string(&port->port, data, urb->actual_length);
	tty_flip_buffer_push(&port->port);
	}

	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
	dev_dbg(&port->dev, "%s - Send read URB returns: %i\n", __func__, result);
	}


	static void kobil_write_int_callback(struct urb *urb)
	{
	}


	static int kobil_write(struct tty_struct tty, struct usb_serial_port port,
	const unsigned char *buf, int count)
	{
	int length = 0;
	int result = 0;
	int todo = 0;
	struct kobil_private *priv;

	if (count == 0) {
	dev_dbg(&port->dev, "%s - write request of 0 bytes\n", __func__);
	return 0;
	}

	priv = usb_get_serial_port_data(port);

	if (count > (KOBIL_BUF_LENGTH - priv->filled)) {
	dev_dbg(&port->dev, "%s - Error: write request bigger than buffer size\n", __func__);
	return -ENOMEM;
	}

	/* Copy data to buffer */
	memcpy(priv->buf + priv->filled, buf, count);
	usb_serial_debug_data(&port->dev, __func__, count, priv->buf + priv->filled);
	priv->filled = priv->filled + count;

	/* only send complete block. TWIN, KAAN SIM and adapter K
	use the same protocol. */
	if (((priv->device_type != KOBIL_ADAPTER_B_PRODUCT_ID) && (priv->filled > 2) && (priv->filled >= (priv->buf[1] + 3))) \|\|
	((priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID) && (priv->filled > 3) && (priv->filled >= (priv->buf[2] + 4)))) {
	/* stop reading (except TWIN and KAAN SIM) */
	if ((priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID)
	\|\| (priv->device_type == KOBIL_ADAPTER_K_PRODUCT_ID))
	usb_kill_urb(port->interrupt_in_urb);

	todo = priv->filled - priv->cur_pos;

	while (todo > 0) {
	/* max 8 byte in one urb (endpoint size) */
	length = min(todo, port->interrupt_out_size);
	/* copy data to transfer buffer */
	memcpy(port->interrupt_out_buffer,
	priv->buf + priv->cur_pos, length);
	port->interrupt_out_urb->transfer_buffer_length = length;

	priv->cur_pos = priv->cur_pos + length;
	result = usb_submit_urb(port->interrupt_out_urb,
	GFP_ATOMIC);
	dev_dbg(&port->dev, "%s - Send write URB returns: %i\n", __func__, result);
	todo = priv->filled - priv->cur_pos;

	if (todo > 0)
	msleep(24);
	}

	priv->filled = 0;
	priv->cur_pos = 0;

	/* start reading (except TWIN and KAAN SIM) */
	if (priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID \|\|
	priv->device_type == KOBIL_ADAPTER_K_PRODUCT_ID) {
	result = usb_submit_urb(port->interrupt_in_urb,
	GFP_ATOMIC);
	dev_dbg(&port->dev, "%s - Send read URB returns: %i\n", __func__, result);
	}
	}
	return count;
	}


	static int kobil_write_room(struct tty_struct *tty)
	{
	/* FIXME */
	return 8;
	}


	static int kobil_tiocmget(struct tty_struct *tty)
	{
	struct usb_serial_port *port = tty->driver_data;
	struct kobil_private *priv;
	int result;
	unsigned char *transfer_buffer;
	int transfer_buffer_length = 8;

	priv = usb_get_serial_port_data(port);
	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID
	\|\| priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
	/* This device doesn't support ioctl calls */
	return -EINVAL;
	}

	/* allocate memory for transfer buffer */
	transfer_buffer = kzalloc(transfer_buffer_length, GFP_KERNEL);
	if (!transfer_buffer)
	return -ENOMEM;

	result = usb_control_msg(port->serial->dev,
	usb_rcvctrlpipe(port->serial->dev, 0),
	SUSBCRequest_GetStatusLineState,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_IN,
	0,
	0,
	transfer_buffer,
	transfer_buffer_length,
	KOBIL_TIMEOUT);

	dev_dbg(&port->dev, "Send get_status_line_state URB returns: %i\n",
	result);
	if (result < 1) {
	if (result >= 0)
	result = -EIO;
	goto out_free;
	}

	dev_dbg(&port->dev, "Statusline: %02x\n", transfer_buffer[0]);

	result = 0;
	if ((transfer_buffer[0] & SUSBCR_GSL_DSR) != 0)
	result = TIOCM_DSR;
	out_free:
	kfree(transfer_buffer);
	return result;
	}

	static int kobil_tiocmset(struct tty_struct *tty,
	unsigned int set, unsigned int clear)
	{
	struct usb_serial_port *port = tty->driver_data;
	struct device *dev = &port->dev;
	struct kobil_private *priv;
	int result;
	int dtr = 0;
	int rts = 0;

	/* FIXME: locking ? */
	priv = usb_get_serial_port_data(port);
	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID
	\|\| priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
	/* This device doesn't support ioctl calls */
	return -EINVAL;
	}

	if (set & TIOCM_RTS)
	rts = 1;
	if (set & TIOCM_DTR)
	dtr = 1;
	if (clear & TIOCM_RTS)
	rts = 0;
	if (clear & TIOCM_DTR)
	dtr = 0;

	if (priv->device_type == KOBIL_ADAPTER_B_PRODUCT_ID) {
	if (dtr != 0)
	dev_dbg(dev, "%s - Setting DTR\n", __func__);
	else
	dev_dbg(dev, "%s - Clearing DTR\n", __func__);
	result = usb_control_msg(port->serial->dev,
	usb_sndctrlpipe(port->serial->dev, 0),
	SUSBCRequest_SetStatusLinesOrQueues,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	((dtr != 0) ? SUSBCR_SSL_SETDTR : SUSBCR_SSL_CLRDTR),
	0,
	NULL,
	0,
	KOBIL_TIMEOUT);
	} else {
	if (rts != 0)
	dev_dbg(dev, "%s - Setting RTS\n", __func__);
	else
	dev_dbg(dev, "%s - Clearing RTS\n", __func__);
	result = usb_control_msg(port->serial->dev,
	usb_sndctrlpipe(port->serial->dev, 0),
	SUSBCRequest_SetStatusLinesOrQueues,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	((rts != 0) ? SUSBCR_SSL_SETRTS : SUSBCR_SSL_CLRRTS),
	0,
	NULL,
	0,
	KOBIL_TIMEOUT);
	}
	dev_dbg(dev, "%s - Send set_status_line URB returns: %i\n", __func__, result);
	return (result < 0) ? result : 0;
	}

	static void kobil_set_termios(struct tty_struct *tty,
	struct usb_serial_port port, struct ktermios old)
	{
	struct kobil_private *priv;
	int result;
	unsigned short urb_val = 0;
	int c_cflag = tty->termios.c_cflag;
	speed_t speed;

	priv = usb_get_serial_port_data(port);
	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID \|\|
	priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID) {
	/* This device doesn't support ioctl calls */
	tty_termios_copy_hw(&tty->termios, old);
	return;
	}

	speed = tty_get_baud_rate(tty);
	switch (speed) {
	case 1200:
	urb_val = SUSBCR_SBR_1200;
	break;
	default:
	speed = 9600;
	fallthrough;
	case 9600:
	urb_val = SUSBCR_SBR_9600;
	break;
	}
	urb_val \|= (c_cflag & CSTOPB) ? SUSBCR_SPASB_2StopBits :
	SUSBCR_SPASB_1StopBit;
	if (c_cflag & PARENB) {
	if (c_cflag & PARODD)
	urb_val \|= SUSBCR_SPASB_OddParity;
	else
	urb_val \|= SUSBCR_SPASB_EvenParity;
	} else
	urb_val \|= SUSBCR_SPASB_NoParity;
	tty->termios.c_cflag &= ~CMSPAR;
	tty_encode_baud_rate(tty, speed, speed);

	result = usb_control_msg(port->serial->dev,
	usb_sndctrlpipe(port->serial->dev, 0),
	SUSBCRequest_SetBaudRateParityAndStopBits,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	urb_val,
	0,
	NULL,
	0,
	KOBIL_TIMEOUT
	);
	if (result) {
	dev_err(&port->dev, "failed to update line settings: %d\n",
	result);
	}
	}

	static int kobil_ioctl(struct tty_struct *tty,
	unsigned int cmd, unsigned long arg)
	{
	struct usb_serial_port *port = tty->driver_data;
	struct kobil_private *priv = usb_get_serial_port_data(port);
	int result;

	if (priv->device_type == KOBIL_USBTWIN_PRODUCT_ID \|\|
	priv->device_type == KOBIL_KAAN_SIM_PRODUCT_ID)
	/* This device doesn't support ioctl calls */
	return -ENOIOCTLCMD;

	switch (cmd) {
	case TCFLSH:
	result = usb_control_msg(port->serial->dev,
	usb_sndctrlpipe(port->serial->dev, 0),
	SUSBCRequest_Misc,
	USB_TYPE_VENDOR \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	SUSBCR_MSC_ResetAllQueues,
	0,
	NULL,
	0,
	KOBIL_TIMEOUT
	);

	dev_dbg(&port->dev,
	"%s - Send reset_all_queues (FLUSH) URB returns: %i\n",
	__func__, result);
	return (result < 0) ? -EIO: 0;
	default:
	return -ENOIOCTLCMD;
	}
	}

	module_usb_serial_driver(serial_drivers, id_table);

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