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v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Symbol USB barcode to serial driver
  4 *
  5 * Copyright (C) 2013 Johan Hovold <jhovold@gmail.com>
  6 * Copyright (C) 2009 Greg Kroah-Hartman <gregkh@suse.de>
  7 * Copyright (C) 2009 Novell Inc.
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/tty.h>
 12#include <linux/slab.h>
 13#include <linux/tty_driver.h>
 14#include <linux/tty_flip.h>
 15#include <linux/module.h>
 16#include <linux/usb.h>
 17#include <linux/usb/serial.h>
 18#include <linux/uaccess.h>
 19
 20static const struct usb_device_id id_table[] = {
 21	{ USB_DEVICE(0x05e0, 0x0600) },
 22	{ },
 23};
 24MODULE_DEVICE_TABLE(usb, id_table);
 25
 26struct symbol_private {
 27	spinlock_t lock;	/* protects the following flags */
 28	bool throttled;
 29	bool actually_throttled;
 30};
 31
 32static void symbol_int_callback(struct urb *urb)
 33{
 34	struct usb_serial_port *port = urb->context;
 35	struct symbol_private *priv = usb_get_serial_port_data(port);
 36	unsigned char *data = urb->transfer_buffer;
 37	int status = urb->status;
 38	unsigned long flags;
 39	int result;
 40	int data_length;
 41
 42	switch (status) {
 43	case 0:
 44		/* success */
 45		break;
 46	case -ECONNRESET:
 47	case -ENOENT:
 48	case -ESHUTDOWN:
 49		/* this urb is terminated, clean up */
 50		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
 51			__func__, status);
 52		return;
 53	default:
 54		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
 55			__func__, status);
 56		goto exit;
 57	}
 58
 59	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 60
 61	/*
 62	 * Data from the device comes with a 1 byte header:
 63	 *
 64	 * <size of data> <data>...
 65	 */
 66	if (urb->actual_length > 1) {
 67		data_length = data[0];
 68		if (data_length > (urb->actual_length - 1))
 69			data_length = urb->actual_length - 1;
 70		tty_insert_flip_string(&port->port, &data[1], data_length);
 71		tty_flip_buffer_push(&port->port);
 72	} else {
 73		dev_dbg(&port->dev, "%s - short packet\n", __func__);
 74	}
 75
 76exit:
 77	spin_lock_irqsave(&priv->lock, flags);
 78
 79	/* Continue trying to always read if we should */
 80	if (!priv->throttled) {
 81		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 82		if (result)
 83			dev_err(&port->dev,
 84			    "%s - failed resubmitting read urb, error %d\n",
 85							__func__, result);
 86	} else
 87		priv->actually_throttled = true;
 88	spin_unlock_irqrestore(&priv->lock, flags);
 89}
 90
 91static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)
 92{
 93	struct symbol_private *priv = usb_get_serial_port_data(port);
 94	unsigned long flags;
 95	int result = 0;
 96
 97	spin_lock_irqsave(&priv->lock, flags);
 98	priv->throttled = false;
 99	priv->actually_throttled = false;
100	spin_unlock_irqrestore(&priv->lock, flags);
101
102	/* Start reading from the device */
103	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
104	if (result)
105		dev_err(&port->dev,
106			"%s - failed resubmitting read urb, error %d\n",
107			__func__, result);
108	return result;
109}
110
111static void symbol_close(struct usb_serial_port *port)
112{
113	usb_kill_urb(port->interrupt_in_urb);
114}
115
116static void symbol_throttle(struct tty_struct *tty)
117{
118	struct usb_serial_port *port = tty->driver_data;
119	struct symbol_private *priv = usb_get_serial_port_data(port);
120
121	spin_lock_irq(&priv->lock);
122	priv->throttled = true;
123	spin_unlock_irq(&priv->lock);
124}
125
126static void symbol_unthrottle(struct tty_struct *tty)
127{
128	struct usb_serial_port *port = tty->driver_data;
129	struct symbol_private *priv = usb_get_serial_port_data(port);
130	int result;
131	bool was_throttled;
132
133	spin_lock_irq(&priv->lock);
134	priv->throttled = false;
135	was_throttled = priv->actually_throttled;
136	priv->actually_throttled = false;
137	spin_unlock_irq(&priv->lock);
138
139	if (was_throttled) {
140		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
141		if (result)
142			dev_err(&port->dev,
143				"%s - failed submitting read urb, error %d\n",
144							__func__, result);
145	}
146}
147
148static int symbol_port_probe(struct usb_serial_port *port)
149{
150	struct symbol_private *priv;
151
152	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
153	if (!priv)
154		return -ENOMEM;
155
156	spin_lock_init(&priv->lock);
157
158	usb_set_serial_port_data(port, priv);
159
160	return 0;
161}
162
163static void symbol_port_remove(struct usb_serial_port *port)
164{
165	struct symbol_private *priv = usb_get_serial_port_data(port);
166
167	kfree(priv);
 
 
168}
169
170static struct usb_serial_driver symbol_device = {
171	.driver = {
172		.owner =	THIS_MODULE,
173		.name =		"symbol",
174	},
175	.id_table =		id_table,
176	.num_ports =		1,
177	.num_interrupt_in =	1,
178	.port_probe =		symbol_port_probe,
179	.port_remove =		symbol_port_remove,
180	.open =			symbol_open,
181	.close =		symbol_close,
182	.throttle = 		symbol_throttle,
183	.unthrottle =		symbol_unthrottle,
184	.read_int_callback =	symbol_int_callback,
185};
186
187static struct usb_serial_driver * const serial_drivers[] = {
188	&symbol_device, NULL
189};
190
191module_usb_serial_driver(serial_drivers, id_table);
192
193MODULE_LICENSE("GPL v2");
v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Symbol USB barcode to serial driver
  4 *
  5 * Copyright (C) 2013 Johan Hovold <jhovold@gmail.com>
  6 * Copyright (C) 2009 Greg Kroah-Hartman <gregkh@suse.de>
  7 * Copyright (C) 2009 Novell Inc.
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/tty.h>
 12#include <linux/slab.h>
 13#include <linux/tty_driver.h>
 14#include <linux/tty_flip.h>
 15#include <linux/module.h>
 16#include <linux/usb.h>
 17#include <linux/usb/serial.h>
 18#include <linux/uaccess.h>
 19
 20static const struct usb_device_id id_table[] = {
 21	{ USB_DEVICE(0x05e0, 0x0600) },
 22	{ },
 23};
 24MODULE_DEVICE_TABLE(usb, id_table);
 25
 26struct symbol_private {
 27	spinlock_t lock;	/* protects the following flags */
 28	bool throttled;
 29	bool actually_throttled;
 30};
 31
 32static void symbol_int_callback(struct urb *urb)
 33{
 34	struct usb_serial_port *port = urb->context;
 35	struct symbol_private *priv = usb_get_serial_port_data(port);
 36	unsigned char *data = urb->transfer_buffer;
 37	int status = urb->status;
 
 38	int result;
 39	int data_length;
 40
 41	switch (status) {
 42	case 0:
 43		/* success */
 44		break;
 45	case -ECONNRESET:
 46	case -ENOENT:
 47	case -ESHUTDOWN:
 48		/* this urb is terminated, clean up */
 49		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
 50			__func__, status);
 51		return;
 52	default:
 53		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
 54			__func__, status);
 55		goto exit;
 56	}
 57
 58	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 59
 60	/*
 61	 * Data from the device comes with a 1 byte header:
 62	 *
 63	 * <size of data> <data>...
 64	 */
 65	if (urb->actual_length > 1) {
 66		data_length = data[0];
 67		if (data_length > (urb->actual_length - 1))
 68			data_length = urb->actual_length - 1;
 69		tty_insert_flip_string(&port->port, &data[1], data_length);
 70		tty_flip_buffer_push(&port->port);
 71	} else {
 72		dev_dbg(&port->dev, "%s - short packet\n", __func__);
 73	}
 74
 75exit:
 76	spin_lock(&priv->lock);
 77
 78	/* Continue trying to always read if we should */
 79	if (!priv->throttled) {
 80		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 81		if (result)
 82			dev_err(&port->dev,
 83			    "%s - failed resubmitting read urb, error %d\n",
 84							__func__, result);
 85	} else
 86		priv->actually_throttled = true;
 87	spin_unlock(&priv->lock);
 88}
 89
 90static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)
 91{
 92	struct symbol_private *priv = usb_get_serial_port_data(port);
 93	unsigned long flags;
 94	int result = 0;
 95
 96	spin_lock_irqsave(&priv->lock, flags);
 97	priv->throttled = false;
 98	priv->actually_throttled = false;
 99	spin_unlock_irqrestore(&priv->lock, flags);
100
101	/* Start reading from the device */
102	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
103	if (result)
104		dev_err(&port->dev,
105			"%s - failed resubmitting read urb, error %d\n",
106			__func__, result);
107	return result;
108}
109
110static void symbol_close(struct usb_serial_port *port)
111{
112	usb_kill_urb(port->interrupt_in_urb);
113}
114
115static void symbol_throttle(struct tty_struct *tty)
116{
117	struct usb_serial_port *port = tty->driver_data;
118	struct symbol_private *priv = usb_get_serial_port_data(port);
119
120	spin_lock_irq(&priv->lock);
121	priv->throttled = true;
122	spin_unlock_irq(&priv->lock);
123}
124
125static void symbol_unthrottle(struct tty_struct *tty)
126{
127	struct usb_serial_port *port = tty->driver_data;
128	struct symbol_private *priv = usb_get_serial_port_data(port);
129	int result;
130	bool was_throttled;
131
132	spin_lock_irq(&priv->lock);
133	priv->throttled = false;
134	was_throttled = priv->actually_throttled;
135	priv->actually_throttled = false;
136	spin_unlock_irq(&priv->lock);
137
138	if (was_throttled) {
139		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
140		if (result)
141			dev_err(&port->dev,
142				"%s - failed submitting read urb, error %d\n",
143							__func__, result);
144	}
145}
146
147static int symbol_port_probe(struct usb_serial_port *port)
148{
149	struct symbol_private *priv;
150
151	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
152	if (!priv)
153		return -ENOMEM;
154
155	spin_lock_init(&priv->lock);
156
157	usb_set_serial_port_data(port, priv);
158
159	return 0;
160}
161
162static int symbol_port_remove(struct usb_serial_port *port)
163{
164	struct symbol_private *priv = usb_get_serial_port_data(port);
165
166	kfree(priv);
167
168	return 0;
169}
170
171static struct usb_serial_driver symbol_device = {
172	.driver = {
173		.owner =	THIS_MODULE,
174		.name =		"symbol",
175	},
176	.id_table =		id_table,
177	.num_ports =		1,
178	.num_interrupt_in =	1,
179	.port_probe =		symbol_port_probe,
180	.port_remove =		symbol_port_remove,
181	.open =			symbol_open,
182	.close =		symbol_close,
183	.throttle = 		symbol_throttle,
184	.unthrottle =		symbol_unthrottle,
185	.read_int_callback =	symbol_int_callback,
186};
187
188static struct usb_serial_driver * const serial_drivers[] = {
189	&symbol_device, NULL
190};
191
192module_usb_serial_driver(serial_drivers, id_table);
193
194MODULE_LICENSE("GPL v2");