[linux-2.6-block.git] / 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);
}

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;
}

static void symbol_close(struct usb_serial_port *port)
{
	usb_kill_urb(port->interrupt_in_urb);
}

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);
}

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);
	}
}

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;
}

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;
}

static int symbol_port_remove(struct usb_serial_port *port)
{
	struct symbol_private *priv = usb_get_serial_port_data(port);

	kfree(priv);

	return 0;
}

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");
Commit	Line	Data
68b44eae GKH	1	/*
	2	* Symbol USB barcode to serial driver
	3	*
a85796ee	4	* Copyright (C) 2013 Johan Hovold <jhovold@gmail.com>
68b44eae GKH	5	* Copyright (C) 2009 Greg Kroah-Hartman <gregkh@suse.de>
	6	* Copyright (C) 2009 Novell Inc.
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License version
	10	* 2 as published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/kernel.h>
68b44eae	14	#include <linux/tty.h>
5a0e3ad6	15	#include <linux/slab.h>
68b44eae GKH	16	#include <linux/tty_driver.h>
	17	#include <linux/tty_flip.h>
	18	#include <linux/module.h>
	19	#include <linux/usb.h>
	20	#include <linux/usb/serial.h>
	21	#include <linux/uaccess.h>
	22
7d40d7e8	23	static const struct usb_device_id id_table[] = {
68b44eae GKH	24	{ USB_DEVICE(0x05e0, 0x0600) },
	25	{ },
	26	};
	27	MODULE_DEVICE_TABLE(usb, id_table);
	28
68b44eae	29	struct symbol_private {
68b44eae GKH	30	spinlock_t lock; /* protects the following flags */
	31	bool throttled;
	32	bool actually_throttled;
68b44eae GKH	33	};
	34
	35	static void symbol_int_callback(struct urb *urb)
	36	{
cced926f	37	struct usb_serial_port *port = urb->context;
a85796ee	38	struct symbol_private *priv = usb_get_serial_port_data(port);
68b44eae	39	unsigned char *data = urb->transfer_buffer;
68b44eae	40	int status = urb->status;
68b44eae	41	int result;
68b44eae GKH	42	int data_length;
68b44eae GKH	43
68b44eae GKH	44	switch (status) {
	45	case 0:
	46	/* success */
	47	break;
	48	case -ECONNRESET:
	49	case -ENOENT:
	50	case -ESHUTDOWN:
	51	/* this urb is terminated, clean up */
e4083ea5 GKH	52	dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
e4083ea5 GKH	53	__func__, status);
68b44eae GKH	54	return;
68b44eae GKH	55	default:
e4083ea5 GKH	56	dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
e4083ea5 GKH	57	__func__, status);
68b44eae GKH	58	goto exit;
	59	}
	60
59d33f2f	61	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
68b44eae	62
8ae25a35 PH	63	/*
	64	* Data from the device comes with a 1 byte header:
	65	*
	66	* <size of data> <data>...
	67	*/
68b44eae	68	if (urb->actual_length > 1) {
8ae25a35 PH	69	data_length = data[0];
	70	if (data_length > (urb->actual_length - 1))
	71	data_length = urb->actual_length - 1;
2e124b4a JS	72	tty_insert_flip_string(&port->port, &data[1], data_length);
2e124b4a JS	73	tty_flip_buffer_push(&port->port);
68b44eae	74	} else {
d9a38a87	75	dev_dbg(&port->dev, "%s - short packet\n", __func__);
68b44eae GKH	76	}
	77
	78	exit:
	79	spin_lock(&priv->lock);
	80
	81	/* Continue trying to always read if we should */
	82	if (!priv->throttled) {
cced926f	83	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
68b44eae GKH	84	if (result)
	85	dev_err(&port->dev,
	86	"%s - failed resubmitting read urb, error %d\n",
	87	__func__, result);
	88	} else
	89	priv->actually_throttled = true;
	90	spin_unlock(&priv->lock);
	91	}
	92
a509a7e4	93	static int symbol_open(struct tty_struct tty, struct usb_serial_port port)
68b44eae	94	{
951d3793	95	struct symbol_private *priv = usb_get_serial_port_data(port);
68b44eae GKH	96	unsigned long flags;
	97	int result = 0;
	98
68b44eae GKH	99	spin_lock_irqsave(&priv->lock, flags);
	100	priv->throttled = false;
	101	priv->actually_throttled = false;
68b44eae GKH	102	spin_unlock_irqrestore(&priv->lock, flags);
68b44eae GKH	103
68b44eae	104	/* Start reading from the device */
cced926f	105	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
68b44eae GKH	106	if (result)
	107	dev_err(&port->dev,
	108	"%s - failed resubmitting read urb, error %d\n",
	109	__func__, result);
	110	return result;
	111	}
	112
335f8514	113	static void symbol_close(struct usb_serial_port *port)
68b44eae	114	{
cced926f	115	usb_kill_urb(port->interrupt_in_urb);
68b44eae GKH	116	}
	117
	118	static void symbol_throttle(struct tty_struct *tty)
	119	{
	120	struct usb_serial_port *port = tty->driver_data;
951d3793	121	struct symbol_private *priv = usb_get_serial_port_data(port);
68b44eae	122
63832515	123	spin_lock_irq(&priv->lock);
68b44eae	124	priv->throttled = true;
63832515	125	spin_unlock_irq(&priv->lock);
68b44eae GKH	126	}
	127
	128	static void symbol_unthrottle(struct tty_struct *tty)
	129	{
	130	struct usb_serial_port *port = tty->driver_data;
951d3793	131	struct symbol_private *priv = usb_get_serial_port_data(port);
68b44eae	132	int result;
b2a5cf1b	133	bool was_throttled;
68b44eae	134
63832515	135	spin_lock_irq(&priv->lock);
68b44eae	136	priv->throttled = false;
b2a5cf1b	137	was_throttled = priv->actually_throttled;
68b44eae	138	priv->actually_throttled = false;
63832515	139	spin_unlock_irq(&priv->lock);
68b44eae	140
b2a5cf1b	141	if (was_throttled) {
cced926f	142	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
b2a5cf1b ON	143	if (result)
	144	dev_err(&port->dev,
	145	"%s - failed submitting read urb, error %d\n",
68b44eae	146	__func__, result);
b2a5cf1b	147	}
68b44eae GKH	148	}
	149
	150	static int symbol_startup(struct usb_serial *serial)
	151	{
cced926f JH	152	if (!serial->num_interrupt_in) {
	153	dev_err(&serial->dev->dev, "no interrupt-in endpoint\n");
	154	return -ENODEV;
	155	}
68b44eae	156
a85796ee JH	157	return 0;
	158	}
	159
	160	static int symbol_port_probe(struct usb_serial_port *port)
	161	{
	162	struct symbol_private *priv;
	163
68b44eae	164	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
a85796ee	165	if (!priv)
68b44eae	166	return -ENOMEM;
a85796ee	167
68b44eae	168	spin_lock_init(&priv->lock);
68b44eae	169
a85796ee JH	170	usb_set_serial_port_data(port, priv);
a85796ee JH	171
68b44eae	172	return 0;
f9c99bb8 AS	173	}
f9c99bb8 AS	174
a85796ee	175	static int symbol_port_remove(struct usb_serial_port *port)
f9c99bb8	176	{
a85796ee	177	struct symbol_private *priv = usb_get_serial_port_data(port);
f9c99bb8	178
68b44eae	179	kfree(priv);
a85796ee JH	180
a85796ee JH	181	return 0;
68b44eae GKH	182	}
68b44eae GKH	183
68b44eae GKH	184	static struct usb_serial_driver symbol_device = {
	185	.driver = {
	186	.owner = THIS_MODULE,
	187	.name = "symbol",
	188	},
	189	.id_table = id_table,
68b44eae GKH	190	.num_ports = 1,
68b44eae GKH	191	.attach = symbol_startup,
a85796ee JH	192	.port_probe = symbol_port_probe,
a85796ee JH	193	.port_remove = symbol_port_remove,
68b44eae GKH	194	.open = symbol_open,
68b44eae GKH	195	.close = symbol_close,
68b44eae GKH	196	.throttle = symbol_throttle,
68b44eae GKH	197	.unthrottle = symbol_unthrottle,
cced926f	198	.read_int_callback = symbol_int_callback,
68b44eae GKH	199	};
68b44eae GKH	200
d860322f AS	201	static struct usb_serial_driver * const serial_drivers[] = {
	202	&symbol_device, NULL
	203	};
	204
68e24113	205	module_usb_serial_driver(serial_drivers, id_table);
68b44eae	206
68b44eae	207	MODULE_LICENSE("GPL");