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v4.6
  1/*
  2 * Symbol USB barcode to serial driver
  3 *
  4 * Copyright (C) 2013 Johan Hovold <jhovold@gmail.com>
  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>
 14#include <linux/tty.h>
 15#include <linux/slab.h>
 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
 23static const struct usb_device_id id_table[] = {
 24	{ USB_DEVICE(0x05e0, 0x0600) },
 25	{ },
 26};
 27MODULE_DEVICE_TABLE(usb, id_table);
 28
 29struct symbol_private {
 30	spinlock_t lock;	/* protects the following flags */
 31	bool throttled;
 32	bool actually_throttled;
 33};
 34
 35static void symbol_int_callback(struct urb *urb)
 36{
 37	struct usb_serial_port *port = urb->context;
 38	struct symbol_private *priv = usb_get_serial_port_data(port);
 39	unsigned char *data = urb->transfer_buffer;
 40	int status = urb->status;
 41	int result;
 42	int data_length;
 43
 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 */
 52		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
 53			__func__, status);
 54		return;
 55	default:
 56		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
 57			__func__, status);
 58		goto exit;
 59	}
 60
 61	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 62
 63	/*
 64	 * Data from the device comes with a 1 byte header:
 65	 *
 66	 * <size of data> <data>...
 67	 */
 68	if (urb->actual_length > 1) {
 69		data_length = data[0];
 70		if (data_length > (urb->actual_length - 1))
 71			data_length = urb->actual_length - 1;
 
 
 
 
 
 
 
 72		tty_insert_flip_string(&port->port, &data[1], data_length);
 73		tty_flip_buffer_push(&port->port);
 74	} else {
 75		dev_dbg(&port->dev, "%s - short packet\n", __func__);
 76	}
 77
 78exit:
 79	spin_lock(&priv->lock);
 80
 81	/* Continue trying to always read if we should */
 82	if (!priv->throttled) {
 83		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 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
 93static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)
 94{
 95	struct symbol_private *priv = usb_get_serial_port_data(port);
 96	unsigned long flags;
 97	int result = 0;
 98
 99	spin_lock_irqsave(&priv->lock, flags);
100	priv->throttled = false;
101	priv->actually_throttled = false;
102	spin_unlock_irqrestore(&priv->lock, flags);
103
104	/* Start reading from the device */
105	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
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
113static void symbol_close(struct usb_serial_port *port)
114{
115	usb_kill_urb(port->interrupt_in_urb);
116}
117
118static void symbol_throttle(struct tty_struct *tty)
119{
120	struct usb_serial_port *port = tty->driver_data;
121	struct symbol_private *priv = usb_get_serial_port_data(port);
122
123	spin_lock_irq(&priv->lock);
124	priv->throttled = true;
125	spin_unlock_irq(&priv->lock);
126}
127
128static void symbol_unthrottle(struct tty_struct *tty)
129{
130	struct usb_serial_port *port = tty->driver_data;
131	struct symbol_private *priv = usb_get_serial_port_data(port);
132	int result;
133	bool was_throttled;
134
135	spin_lock_irq(&priv->lock);
136	priv->throttled = false;
137	was_throttled = priv->actually_throttled;
138	priv->actually_throttled = false;
139	spin_unlock_irq(&priv->lock);
140
141	if (was_throttled) {
142		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
143		if (result)
144			dev_err(&port->dev,
145				"%s - failed submitting read urb, error %d\n",
146							__func__, result);
147	}
148}
149
150static int symbol_startup(struct usb_serial *serial)
151{
152	if (!serial->num_interrupt_in) {
153		dev_err(&serial->dev->dev, "no interrupt-in endpoint\n");
154		return -ENODEV;
155	}
156
157	return 0;
158}
159
160static int symbol_port_probe(struct usb_serial_port *port)
161{
162	struct symbol_private *priv;
163
164	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
165	if (!priv)
166		return -ENOMEM;
167
168	spin_lock_init(&priv->lock);
169
170	usb_set_serial_port_data(port, priv);
171
172	return 0;
173}
174
175static int symbol_port_remove(struct usb_serial_port *port)
176{
177	struct symbol_private *priv = usb_get_serial_port_data(port);
178
179	kfree(priv);
180
181	return 0;
182}
183
184static struct usb_serial_driver symbol_device = {
185	.driver = {
186		.owner =	THIS_MODULE,
187		.name =		"symbol",
188	},
189	.id_table =		id_table,
190	.num_ports =		1,
191	.attach =		symbol_startup,
192	.port_probe =		symbol_port_probe,
193	.port_remove =		symbol_port_remove,
194	.open =			symbol_open,
195	.close =		symbol_close,
196	.throttle = 		symbol_throttle,
197	.unthrottle =		symbol_unthrottle,
198	.read_int_callback =	symbol_int_callback,
199};
200
201static struct usb_serial_driver * const serial_drivers[] = {
202	&symbol_device, NULL
203};
204
205module_usb_serial_driver(serial_drivers, id_table);
206
207MODULE_LICENSE("GPL");
v3.15
  1/*
  2 * Symbol USB barcode to serial driver
  3 *
  4 * Copyright (C) 2013 Johan Hovold <jhovold@gmail.com>
  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>
 14#include <linux/tty.h>
 15#include <linux/slab.h>
 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
 23static const struct usb_device_id id_table[] = {
 24	{ USB_DEVICE(0x05e0, 0x0600) },
 25	{ },
 26};
 27MODULE_DEVICE_TABLE(usb, id_table);
 28
 29struct symbol_private {
 30	spinlock_t lock;	/* protects the following flags */
 31	bool throttled;
 32	bool actually_throttled;
 33};
 34
 35static void symbol_int_callback(struct urb *urb)
 36{
 37	struct usb_serial_port *port = urb->context;
 38	struct symbol_private *priv = usb_get_serial_port_data(port);
 39	unsigned char *data = urb->transfer_buffer;
 40	int status = urb->status;
 41	int result;
 42	int data_length;
 43
 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 */
 52		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
 53			__func__, status);
 54		return;
 55	default:
 56		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
 57			__func__, status);
 58		goto exit;
 59	}
 60
 61	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 62
 
 
 
 
 
 63	if (urb->actual_length > 1) {
 64		data_length = urb->actual_length - 1;
 65
 66		/*
 67		 * Data from the device comes with a 1 byte header:
 68		 *
 69		 * <size of data>data...
 70		 * 	This is real data to be sent to the tty layer
 71		 * we pretty much just ignore the size and send everything
 72		 * else to the tty layer.
 73		 */
 74		tty_insert_flip_string(&port->port, &data[1], data_length);
 75		tty_flip_buffer_push(&port->port);
 76	} else {
 77		dev_dbg(&port->dev, "%s - short packet\n", __func__);
 78	}
 79
 80exit:
 81	spin_lock(&priv->lock);
 82
 83	/* Continue trying to always read if we should */
 84	if (!priv->throttled) {
 85		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 86		if (result)
 87			dev_err(&port->dev,
 88			    "%s - failed resubmitting read urb, error %d\n",
 89							__func__, result);
 90	} else
 91		priv->actually_throttled = true;
 92	spin_unlock(&priv->lock);
 93}
 94
 95static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)
 96{
 97	struct symbol_private *priv = usb_get_serial_data(port->serial);
 98	unsigned long flags;
 99	int result = 0;
100
101	spin_lock_irqsave(&priv->lock, flags);
102	priv->throttled = false;
103	priv->actually_throttled = false;
104	spin_unlock_irqrestore(&priv->lock, flags);
105
106	/* Start reading from the device */
107	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
108	if (result)
109		dev_err(&port->dev,
110			"%s - failed resubmitting read urb, error %d\n",
111			__func__, result);
112	return result;
113}
114
115static void symbol_close(struct usb_serial_port *port)
116{
117	usb_kill_urb(port->interrupt_in_urb);
118}
119
120static void symbol_throttle(struct tty_struct *tty)
121{
122	struct usb_serial_port *port = tty->driver_data;
123	struct symbol_private *priv = usb_get_serial_data(port->serial);
124
125	spin_lock_irq(&priv->lock);
126	priv->throttled = true;
127	spin_unlock_irq(&priv->lock);
128}
129
130static void symbol_unthrottle(struct tty_struct *tty)
131{
132	struct usb_serial_port *port = tty->driver_data;
133	struct symbol_private *priv = usb_get_serial_data(port->serial);
134	int result;
135	bool was_throttled;
136
137	spin_lock_irq(&priv->lock);
138	priv->throttled = false;
139	was_throttled = priv->actually_throttled;
140	priv->actually_throttled = false;
141	spin_unlock_irq(&priv->lock);
142
143	if (was_throttled) {
144		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
145		if (result)
146			dev_err(&port->dev,
147				"%s - failed submitting read urb, error %d\n",
148							__func__, result);
149	}
150}
151
152static int symbol_startup(struct usb_serial *serial)
153{
154	if (!serial->num_interrupt_in) {
155		dev_err(&serial->dev->dev, "no interrupt-in endpoint\n");
156		return -ENODEV;
157	}
158
159	return 0;
160}
161
162static int symbol_port_probe(struct usb_serial_port *port)
163{
164	struct symbol_private *priv;
165
166	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
167	if (!priv)
168		return -ENOMEM;
169
170	spin_lock_init(&priv->lock);
171
172	usb_set_serial_port_data(port, priv);
173
174	return 0;
175}
176
177static int symbol_port_remove(struct usb_serial_port *port)
178{
179	struct symbol_private *priv = usb_get_serial_port_data(port);
180
181	kfree(priv);
182
183	return 0;
184}
185
186static struct usb_serial_driver symbol_device = {
187	.driver = {
188		.owner =	THIS_MODULE,
189		.name =		"symbol",
190	},
191	.id_table =		id_table,
192	.num_ports =		1,
193	.attach =		symbol_startup,
194	.port_probe =		symbol_port_probe,
195	.port_remove =		symbol_port_remove,
196	.open =			symbol_open,
197	.close =		symbol_close,
198	.throttle = 		symbol_throttle,
199	.unthrottle =		symbol_unthrottle,
200	.read_int_callback =	symbol_int_callback,
201};
202
203static struct usb_serial_driver * const serial_drivers[] = {
204	&symbol_device, NULL
205};
206
207module_usb_serial_driver(serial_drivers, id_table);
208
209MODULE_LICENSE("GPL");