USB: serial: add metro-usb driver to the tree

/*

  Date Created:	9/15/2006

  File Name:		metro-usb.c

  Description:	metro-usb.c is the drivers main source file. The driver is a USB to Serial converter.

		The driver takes USB data and sends it to a virtual ttyUSB# serial port.

		The driver interfaces with the usbserial.ko driver supplied by Linux.

		NOTES:

		To install the driver:

		1. Install the usbserial.ko module supplied by Linux with: # insmod usbserial.ko

		2. Install the metro-usb.ko module with: # insmod metro-usb.ko vender=0x#### product=0x#### debug=1

		   The vendor, product and debug parameters are optional.

		Some of this code is credited to Linux USB open source files that are distributed with Linux.

  Copyright:	2007 Metrologic Instruments. All rights reserved.

  Copyright:	2011 Azimut Ltd. <http://azimutrzn.ru/>

  Requirements: gedit.exe, notepad.exe

  Revision History:

  Date:			Developer:			Revisions:

  ------------------------------------------------------------------------------

  1/30/2007		Philip Nicastro		Initial release. (v1.0.0.0)

  2/27/2007		Philip Nicastro		Changed the metrousb_read_int_callback function to use a loop with the tty_insert_flip_char function to copy each byte to the tty layer. Removed the tty_buffer_request_room and the tty_insert_flip_string function calls. These calls were not supported on Fedora.

  2/27/2007		Philip Nicastro		Released. (v1.1.0.0)

  10/07/2011		Aleksey Babahin		Update for new kernel (tested on 2.6.38)

						Add unidirection mode support

*/

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/tty.h>

#include <linux/module.h>

#include <linux/usb.h>

#include <linux/errno.h>

#include <linux/slab.h>

#include <linux/tty_driver.h>

#include <linux/tty_flip.h>

#include <linux/moduleparam.h>

#include <linux/spinlock.h>

#include <asm/uaccess.h>

#include <linux/errno.h>

#include "metro-usb.h"

#include <linux/usb/serial.h>

/* Version Information */

#define DRIVER_VERSION "v1.2.0.0"

#define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"

/* Device table list. */

static struct usb_device_id id_table [] = {

	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID) },

	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },

	{ }, /* Optional paramenter entry. */

	{ }, /* Terminating entry. */

};

MODULE_DEVICE_TABLE(usb, id_table);

/* Input parameter constants. */

static int debug;

static __u16 vendor;

static __u16 product;

/* Function prototypes. */

static void metrousb_cleanup (struct usb_serial_port *port);

static void metrousb_close (struct usb_serial_port *port);

static int  metrousb_open (struct tty_struct *tty, struct usb_serial_port *port);

static void metrousb_read_int_callback (struct urb *urb);

static void metrousb_shutdown (struct usb_serial *serial);

static int metrousb_startup (struct usb_serial *serial);

static void metrousb_throttle(struct tty_struct *tty);

static int metrousb_tiocmget(struct tty_struct *tty);

static int metrousb_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear);

static void metrousb_unthrottle(struct tty_struct *tty);

/* Driver structure. */

static struct usb_driver metrousb_driver = {

	.name =		"metro-usb",

	.probe =	usb_serial_probe,

	.disconnect =	usb_serial_disconnect,

	.id_table =	id_table

};

/* Device structure. */

static struct usb_serial_driver metrousb_device = {

	.driver = {

		.owner =	THIS_MODULE,

		.name =		"metro-usb",

	},

	.description 		= "Metrologic USB to serial converter.",

	.id_table 		= id_table,

	.usb_driver		= &metrousb_driver,

	.num_ports 		= 1,

	.open 			= metrousb_open,

	.close 			= metrousb_close,

	.read_int_callback 	= metrousb_read_int_callback,

	.attach 		= metrousb_startup,

	.release 		= metrousb_shutdown,

	.throttle          	= metrousb_throttle,

	.unthrottle        	= metrousb_unthrottle,

	.tiocmget          	= metrousb_tiocmget,

	.tiocmset          	= metrousb_tiocmset,

};

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

  Description:

	Clean up any urbs and port information.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static void metrousb_cleanup (struct usb_serial_port *port)

{

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

	if (port->serial->dev) {

		/* Shutdown any interrupt in urbs. */

		if (port->interrupt_in_urb) {

			usb_unlink_urb(port->interrupt_in_urb);

			usb_kill_urb(port->interrupt_in_urb);

		}

		// temp

		// this will be needed for the write urb

		/* Shutdown any interrupt_out_urbs. */

		//if (serial->num_bulk_in)

		//	usb_kill_urb(port->read_urb);

	}

}

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

  Description:

	Close the open serial port. Cleanup any open serial port information.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

	struct file *: pointer to a file structure.

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static void metrousb_close (struct usb_serial_port *port)

{

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

	metrousb_cleanup(port);

}

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

  Description:

	Driver exit.

  Input:

	None:

  Output:

	None:

*/

static void __exit metrousb_exit(void)

{

	dbg("METRO-USB - %s", __FUNCTION__);

	usb_deregister(&metrousb_driver);

	usb_serial_deregister(&metrousb_device);

}

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

  Description:

	Driver initialization.

  Input:

	None:

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static int __init metrousb_init(void)

{

	int retval = 0;

	int i = 0;

	dbg("METRO-USB - %s", __FUNCTION__);

	/* Add the device parameters if entered. */

	if ((vendor > 0) && (product > 0)) {

		struct usb_device_id usb_dev_temp[] = { {USB_DEVICE(vendor, product) } };

		/* Find the last entry in id_table */

		for (i=0; i < ARRAY_SIZE(id_table); i++) {

			if (id_table[i].idVendor == 0) {

				id_table[i] = usb_dev_temp[0];

				break;

			}

		}

		dbg("METRO-USB - %s - support added for unknown device: vendor=0x%x - product=0x%x", __FUNCTION__, vendor, product);

		printk(KERN_INFO "Metro USB-POS support added for unknown device: vendor=0x%x - product=0x%x", vendor, product);

	}

	/* Register the devices. */

	retval = usb_serial_register(&metrousb_device);

	if (retval)

		return retval;

	/* Register the driver. */

	retval = usb_register(&metrousb_driver);

	if (retval)

		usb_serial_deregister(&metrousb_device);

	printk(KERN_INFO DRIVER_DESC " : " DRIVER_VERSION);

	return retval;

}

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

  Description:

	Open the drivers serial port.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

	struct file *: pointer to a file structure.

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static int metrousb_open (struct tty_struct *tty, struct usb_serial_port *port)

{

	struct usb_serial *serial = port->serial;

	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);

	unsigned long flags = 0;

	int result = 0;

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

	/* Make sure the urb is initialized. */

	if (!port->interrupt_in_urb) {

		dbg("METRO-USB - %s - interrupt urb not initialized for port number=%d", __FUNCTION__, port->number);

		return -ENODEV;

	}

	/* Set the private data information for the port. */

	spin_lock_irqsave(&metro_priv->lock, flags);

	metro_priv->control_state = 0;

	metro_priv->throttled = 0;

	spin_unlock_irqrestore(&metro_priv->lock, flags);

	/*

	 * 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.

	 */

	if (tty) {

		tty->low_latency = 1;

	}

	/* Clear the urb pipe. */

	usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);

	/* Start reading from the device */

	usb_fill_int_urb (port->interrupt_in_urb, serial->dev,

			   usb_rcvintpipe (serial->dev, port->interrupt_in_endpointAddress),

			   port->interrupt_in_urb->transfer_buffer,

			   port->interrupt_in_urb->transfer_buffer_length,

			   metrousb_read_int_callback, port, 1);

	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);

	if (result) {

		dbg("METRO-USB - %s - failed submitting interrupt in urb for port number=%d, error code=%d"

			, __FUNCTION__, port->number, result);

		goto exit;

	}

	dbg("METRO-USB - %s - port open for port number=%d", __FUNCTION__, port->number);

exit:

	return result;

}

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

  Description:

	Read the port from the read interrupt.

  Input:

	struct urb *: urb structure to get data.

	struct pt_regs *: pt_regs structure.

  Output:

	None:

*/

static void metrousb_read_int_callback (struct urb *urb)

{

	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;

	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);

	struct tty_struct *tty;

	unsigned char *data = urb->transfer_buffer;

	int throttled = 0;

	int result = 0;

	unsigned long flags = 0;

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

	switch (urb->status) {

		case 0:

			/* Success status, read from the port. */

			break;

		case -ECONNRESET:

		case -ENOENT:

		case -ESHUTDOWN:

			/* urb has been terminated. */

			dbg("METRO-USB - %s - urb shutting down, port number=%d, error code=%d",

				__FUNCTION__, port->number, result);

			return;

		default:

			dbg("METRO-USB - %s - non-zero urb received, port number=%d, error code=%d",

				__FUNCTION__, port->number, result);

			goto exit;

	}

	/* Set the data read from the usb port into the serial port buffer. */

	tty = tty_port_tty_get(&port->port);

	if (!tty) {

		dbg("%s - bad tty pointer - exiting", __func__);

		return;

	}

	if (tty && urb->actual_length) {

		// Loop through the data copying each byte to the tty layer.

		tty_insert_flip_string(tty, data, urb->actual_length);

		// Force the data to the tty layer.

		tty_flip_buffer_push(tty);

	}

	tty_kref_put(tty);

	/* Set any port variables. */

	spin_lock_irqsave(&metro_priv->lock, flags);

	throttled = metro_priv->throttled;

	spin_unlock_irqrestore(&metro_priv->lock, flags);

	/* Continue trying to read if set. */

	if (!throttled) {

		usb_fill_int_urb (port->interrupt_in_urb, port->serial->dev,

				   usb_rcvintpipe (port->serial->dev, port->interrupt_in_endpointAddress),

				   port->interrupt_in_urb->transfer_buffer,

				   port->interrupt_in_urb->transfer_buffer_length,

				   metrousb_read_int_callback, port, 1);

		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);

		if (result) {

			dbg("METRO-USB - %s - failed submitting interrupt in urb for port number=%d, error code=%d",

				__FUNCTION__, port->number, result);

		}

	}

	return;

exit:

	/* Try to resubmit the urb. */

	result = usb_submit_urb (urb, GFP_ATOMIC);

	if (result) {

		dbg("METRO-USB - %s - failed submitting interrupt in urb for port number=%d, error code=%d",

			__FUNCTION__, port->number, result);

	}

}

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

  Description:

	Set the modem control state for the entered serial port.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

	unsigned int: control state value to set.

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)

{

	int retval = 0;

	unsigned char mcr = METROUSB_MCR_NONE;

	dbg("METRO-USB - %s - control state=%d", __FUNCTION__, control_state);

	/* Set the modem control value. */

	if (control_state & TIOCM_DTR)

		mcr |= METROUSB_MCR_DTR;

	if (control_state & TIOCM_RTS)

		mcr |= METROUSB_MCR_RTS;

	/* Send the command to the usb port. */

	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),

				METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,

				control_state, 0, NULL, 0, WDR_TIMEOUT);

	if (retval < 0)

		dbg("METRO-USB - %s - set modem ctrl=0x%x failed, error code=%d", __FUNCTION__, mcr, retval);

	return retval;

}

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

  Description:

	Shutdown the driver.

  Input:

	struct usb_serial *: pointer to a usb-serial structure.

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static void metrousb_shutdown (struct usb_serial *serial)

{

	int i = 0;

	dbg("METRO-USB - %s", __FUNCTION__);

	/* Stop reading and writing on all ports. */

	for (i=0; i < serial->num_ports; ++i) {

		/* Close any open urbs. */

		metrousb_cleanup(serial->port[i]);

		/* Free memory. */

		kfree(usb_get_serial_port_data(serial->port[i]));

		usb_set_serial_port_data(serial->port[i], NULL);

		dbg("METRO-USB - %s - freed port number=%d", __FUNCTION__, serial->port[i]->number);

	}

}

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

  Description:

	Startup the driver.

  Input:

	struct usb_serial *: pointer to a usb-serial structure.

  Output:

	int: Returns true (0) if successful, false otherwise.

*/

static int metrousb_startup(struct usb_serial *serial)

{

	struct metrousb_private *metro_priv;

	struct usb_serial_port *port;

	int i = 0;

	dbg("METRO-USB - %s", __FUNCTION__);

	/* Loop through the serial ports setting up the private structures.

	 * Currently we only use one port. */

	for (i = 0; i < serial->num_ports; ++i) {

		port = serial->port[i];

		/* Declare memory. */

		metro_priv = (struct metrousb_private *) kmalloc (sizeof(struct metrousb_private), GFP_KERNEL);

		if (!metro_priv)

			return -ENOMEM;

		/* Clear memory. */

		memset (metro_priv, 0x00, sizeof(struct metrousb_private));

		/* Initialize memory. */

		spin_lock_init(&metro_priv->lock);

		usb_set_serial_port_data(port, metro_priv);

		dbg("METRO-USB - %s - port number=%d.", __FUNCTION__, port->number);

	}

	return 0;

}

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

  Description:

	Set the serial port throttle to stop reading from the port.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

  Output:

	None:

*/

static void metrousb_throttle (struct tty_struct *tty)

{

	struct usb_serial_port *port = tty->driver_data;

	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);

	unsigned long flags = 0;

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

	/* Set the private information for the port to stop reading data. */

	spin_lock_irqsave(&metro_priv->lock, flags);

	metro_priv->throttled = 1;

	spin_unlock_irqrestore(&metro_priv->lock, flags);

}

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

  Description:

	Get the serial port control line states.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

	struct file *: pointer to a file structure.

  Output:

	int: Returns the state of the control lines.

*/

static int metrousb_tiocmget (struct tty_struct *tty)

{

	unsigned long control_state = 0;

	struct usb_serial_port *port = tty->driver_data;

	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);

	unsigned long flags = 0;

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

	spin_lock_irqsave(&metro_priv->lock, flags);

	control_state = metro_priv->control_state;

	spin_unlock_irqrestore(&metro_priv->lock, flags);

	return control_state;

}

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

  Description:

	Set the serial port control line states.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

	struct file *: pointer to a file structure.

	unsigned int: line state to set.

	unsigned int: line state to clear.

  Output:

	int: Returns the state of the control lines.

*/

static int metrousb_tiocmset (struct tty_struct *tty,

			       unsigned int set, unsigned int clear)

{

	struct usb_serial_port *port = tty->driver_data;

	struct usb_serial *serial = port->serial;

	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);

	unsigned long flags = 0;

	unsigned long control_state = 0;

	dbg("METRO-USB - %s - port number=%d, set=%d, clear=%d", __FUNCTION__, port->number, set, clear);

	spin_lock_irqsave(&metro_priv->lock, flags);

	control_state = metro_priv->control_state;

	// Set the RTS and DTR values.

	if (set & TIOCM_RTS)

		control_state |= TIOCM_RTS;

	if (set & TIOCM_DTR)

		control_state |= TIOCM_DTR;

	if (clear & TIOCM_RTS)

		control_state &= ~TIOCM_RTS;

	if (clear & TIOCM_DTR)

		control_state &= ~TIOCM_DTR;

	metro_priv->control_state = control_state;

	spin_unlock_irqrestore(&metro_priv->lock, flags);

	return metrousb_set_modem_ctrl(serial, control_state);

}

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

  Description:

	Set the serial port unthrottle to resume reading from the port.

  Input:

	struct usb_serial_port *: pointer to a usb_serial_port structure.

  Output:

	None:

*/

static void metrousb_unthrottle (struct tty_struct *tty)

{

	struct usb_serial_port *port = tty->driver_data;

	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);

	unsigned long flags = 0;

	int result = 0;

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

	/* Set the private information for the port to resume reading data. */

	spin_lock_irqsave(&metro_priv->lock, flags);

	metro_priv->throttled = 0;

	spin_unlock_irqrestore(&metro_priv->lock, flags);

	/* Submit the urb to read from the port. */

	port->interrupt_in_urb->dev = port->serial->dev;

	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);

	if (result) {

		dbg("METRO-USB - %s - failed submitting interrupt in urb for port number=%d, error code=%d",

			__FUNCTION__, port->number, result);

	}

}

/* Standard module function. */

module_init(metrousb_init);

module_exit(metrousb_exit);

MODULE_LICENSE("GPL");

MODULE_AUTHOR( "Philip Nicastro" );

MODULE_AUTHOR( "Aleksey Babahin <tamerlan311@gmail.com>" );

MODULE_DESCRIPTION( DRIVER_DESC );

/* Module input parameters */

module_param(debug, bool, S_IRUGO | S_IWUSR);

MODULE_PARM_DESC(debug, "Print debug info (bool 1=on, 0=off)");

module_param(vendor, ushort, 0);

MODULE_PARM_DESC(vendor, "User specified vendor ID (ushort)");

module_param(product, ushort, 0);

MODULE_PARM_DESC(product, "User specified product ID (ushort)");

/*

  Date Created:	1/12/2007

  File Name:		metro-usb.h

  Description:	metro-usb.h is the drivers header file. The driver is a USB to Serial converter.

		The driver takes USB data and sends it to a virtual ttyUSB# serial port.

		The driver interfaces with the usbserial.ko driver supplied by Linux.

		NOTES:

		To install the driver:

		1. Install the usbserial.ko module supplied by Linux with: # insmod usbserial.ko

		2. Install the metro-usb.ko module with: # insmod metro-usb.ko vender=0x#### product=0x#### debug=1

		   The vendor, product and debug parameters are optional.

  Copyright:	2007 Metrologic Instruments. All rights reserved.

  Copyright:	2011 Azimut Ltd. <http://azimutrzn.ru/>

  Requirements: Notepad.exe

  Revision History:

  Date:			Developer:			Revisions:

  ------------------------------------------------------------------------------

  1/12/2007		Philip Nicastro		Initial release. (v1.0.0.0)

  10/07/2011		Aleksey Babahin		Update for new kernel (tested on 2.6.38)

						Add unidirection mode support

*/

#ifndef __LINUX_USB_SERIAL_METRO

#define __LINUX_USB_SERIAL_METRO

/* Product information. */

#define FOCUS_VENDOR_ID		0x0C2E

#define FOCUS_PRODUCT_ID	0x0720

#define FOCUS_PRODUCT_ID_UNI	0x0710

#define METROUSB_SET_REQUEST_TYPE	0x40

#define METROUSB_SET_MODEM_CTRL_REQUEST	10

#define METROUSB_SET_BREAK_REQUEST	0x40

#define METROUSB_MCR_NONE               0x8     /* Deactivate DTR and RTS. */

#define METROUSB_MCR_RTS                0xa     /* Activate RTS. */

#define METROUSB_MCR_DTR                0x9     /* Activate DTR. */

#define WDR_TIMEOUT			5000 	/* default urb timeout. */

/* Private data structure. */

struct metrousb_private {

	spinlock_t lock;

	int throttled;

	unsigned long control_state;

};

#endif