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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");
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");