Release 4.9 drivers/usb/serial/symbolserial.c
  
  
/*
 * Symbol USB barcode to serial driver
 *
 * Copyright (C) 2013 Johan Hovold <jhovold@gmail.com>
 * Copyright (C) 2009 Greg Kroah-Hartman <gregkh@suse.de>
 * Copyright (C) 2009 Novell Inc.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License version
 *      2 as published by the Free Software Foundation.
 */
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/uaccess.h>
static const struct usb_device_id id_table[] = {
	{ USB_DEVICE(0x05e0, 0x0600) },
	{ },
};
MODULE_DEVICE_TABLE(usb, id_table);
struct symbol_private {
	
spinlock_t lock;	/* protects the following flags */
	
bool throttled;
	
bool actually_throttled;
};
static void symbol_int_callback(struct urb *urb)
{
	struct usb_serial_port *port = urb->context;
	struct symbol_private *priv = usb_get_serial_port_data(port);
	unsigned char *data = urb->transfer_buffer;
	int status = urb->status;
	int result;
	int data_length;
	switch (status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
			__func__, status);
		return;
	default:
		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
			__func__, status);
		goto exit;
	}
	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
	/*
         * Data from the device comes with a 1 byte header:
         *
         * <size of data> <data>...
         */
	if (urb->actual_length > 1) {
		data_length = data[0];
		if (data_length > (urb->actual_length - 1))
			data_length = urb->actual_length - 1;
		tty_insert_flip_string(&port->port, &data[1], data_length);
		tty_flip_buffer_push(&port->port);
	} else {
		dev_dbg(&port->dev, "%s - short packet\n", __func__);
	}
exit:
	spin_lock(&priv->lock);
	/* Continue trying to always read if we should */
	if (!priv->throttled) {
		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
		if (result)
			dev_err(&port->dev,
			    "%s - failed resubmitting read urb, error %d\n",
							__func__, result);
	} else
		priv->actually_throttled = true;
	spin_unlock(&priv->lock);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 220 | 82.71% | 2 | 20.00% | 
| philipp hachtmann | philipp hachtmann | 20 | 7.52% | 1 | 10.00% | 
| johan hovold | johan hovold | 17 | 6.39% | 4 | 40.00% | 
| jiri slaby | jiri slaby | 8 | 3.01% | 2 | 20.00% | 
| alan cox | alan cox | 1 | 0.38% | 1 | 10.00% | 
 | Total | 266 | 100.00% | 10 | 100.00% | 
static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)
{
	struct symbol_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	int result = 0;
	spin_lock_irqsave(&priv->lock, flags);
	priv->throttled = false;
	priv->actually_throttled = false;
	spin_unlock_irqrestore(&priv->lock, flags);
	/* Start reading from the device */
	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
	if (result)
		dev_err(&port->dev,
			"%s - failed resubmitting read urb, error %d\n",
			__func__, result);
	return result;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 97 | 97.00% | 1 | 33.33% | 
| johan hovold | johan hovold | 2 | 2.00% | 1 | 33.33% | 
| philipp hachtmann | philipp hachtmann | 1 | 1.00% | 1 | 33.33% | 
 | Total | 100 | 100.00% | 3 | 100.00% | 
static void symbol_close(struct usb_serial_port *port)
{
	usb_kill_urb(port->interrupt_in_urb);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 16 | 88.89% | 1 | 50.00% | 
| johan hovold | johan hovold | 2 | 11.11% | 1 | 50.00% | 
 | Total | 18 | 100.00% | 2 | 100.00% | 
static void symbol_throttle(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct symbol_private *priv = usb_get_serial_port_data(port);
	spin_lock_irq(&priv->lock);
	priv->throttled = true;
	spin_unlock_irq(&priv->lock);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 49 | 94.23% | 1 | 33.33% | 
| oliver neukum | oliver neukum | 2 | 3.85% | 1 | 33.33% | 
| philipp hachtmann | philipp hachtmann | 1 | 1.92% | 1 | 33.33% | 
 | Total | 52 | 100.00% | 3 | 100.00% | 
static void symbol_unthrottle(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct symbol_private *priv = usb_get_serial_port_data(port);
	int result;
	bool was_throttled;
	spin_lock_irq(&priv->lock);
	priv->throttled = false;
	was_throttled = priv->actually_throttled;
	priv->actually_throttled = false;
	spin_unlock_irq(&priv->lock);
	if (was_throttled) {
		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
		if (result)
			dev_err(&port->dev,
				"%s - failed submitting read urb, error %d\n",
							__func__, result);
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 84 | 80.00% | 1 | 20.00% | 
| oliver neukum | oliver neukum | 18 | 17.14% | 2 | 40.00% | 
| johan hovold | johan hovold | 2 | 1.90% | 1 | 20.00% | 
| philipp hachtmann | philipp hachtmann | 1 | 0.95% | 1 | 20.00% | 
 | Total | 105 | 100.00% | 5 | 100.00% | 
static int symbol_startup(struct usb_serial *serial)
{
	if (!serial->num_interrupt_in) {
		dev_err(&serial->dev->dev, "no interrupt-in endpoint\n");
		return -ENODEV;
	}
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| johan hovold | johan hovold | 28 | 71.79% | 2 | 66.67% | 
| greg kroah-hartman | greg kroah-hartman | 11 | 28.21% | 1 | 33.33% | 
 | Total | 39 | 100.00% | 3 | 100.00% | 
static int symbol_port_probe(struct usb_serial_port *port)
{
	struct symbol_private *priv;
	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;
	spin_lock_init(&priv->lock);
	usb_set_serial_port_data(port, priv);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 37 | 66.07% | 1 | 33.33% | 
| johan hovold | johan hovold | 18 | 32.14% | 1 | 33.33% | 
| alan stern | alan stern | 1 | 1.79% | 1 | 33.33% | 
 | Total | 56 | 100.00% | 3 | 100.00% | 
static int symbol_port_remove(struct usb_serial_port *port)
{
	struct symbol_private *priv = usb_get_serial_port_data(port);
	kfree(priv);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 14 | 48.28% | 1 | 33.33% | 
| johan hovold | johan hovold | 9 | 31.03% | 1 | 33.33% | 
| greg kroah-hartman | greg kroah-hartman | 6 | 20.69% | 1 | 33.33% | 
 | Total | 29 | 100.00% | 3 | 100.00% | 
static struct usb_serial_driver symbol_device = {
	.driver = {
		.owner =	THIS_MODULE,
		.name =		"symbol",
        },
	.id_table =		id_table,
	.num_ports =		1,
	.attach =		symbol_startup,
	.port_probe =		symbol_port_probe,
	.port_remove =		symbol_port_remove,
	.open =			symbol_open,
	.close =		symbol_close,
	.throttle = 		symbol_throttle,
	.unthrottle =		symbol_unthrottle,
	.read_int_callback =	symbol_int_callback,
};
static struct usb_serial_driver * const serial_drivers[] = {
	&symbol_device, NULL
};
module_usb_serial_driver(serial_drivers, id_table);
MODULE_LICENSE("GPL");
Overall Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| greg kroah-hartman | greg kroah-hartman | 653 | 78.30% | 4 | 21.05% | 
| johan hovold | johan hovold | 94 | 11.27% | 4 | 21.05% | 
| alan stern | alan stern | 31 | 3.72% | 2 | 10.53% | 
| philipp hachtmann | philipp hachtmann | 23 | 2.76% | 2 | 10.53% | 
| oliver neukum | oliver neukum | 20 | 2.40% | 2 | 10.53% | 
| jiri slaby | jiri slaby | 8 | 0.96% | 2 | 10.53% | 
| tejun heo | tejun heo | 3 | 0.36% | 1 | 5.26% | 
| marton nemeth | marton nemeth | 1 | 0.12% | 1 | 5.26% | 
| alan cox | alan cox | 1 | 0.12% | 1 | 5.26% | 
 | Total | 834 | 100.00% | 19 | 100.00% |