2 * Symbol USB barcode to serial driver
4 * Copyright (C) 2009 Greg Kroah-Hartman <gregkh@suse.de>
5 * Copyright (C) 2009 Novell Inc.
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
12 #include <linux/kernel.h>
13 #include <linux/init.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>
23 static const struct usb_device_id id_table[] = {
24 { USB_DEVICE(0x05e0, 0x0600) },
27 MODULE_DEVICE_TABLE(usb, id_table);
29 /* This structure holds all of the individual device information */
30 struct symbol_private {
31 struct usb_device *udev;
32 struct usb_serial *serial;
33 struct usb_serial_port *port;
34 unsigned char *int_buffer;
39 spinlock_t lock; /* protects the following flags */
41 bool actually_throttled;
45 static void symbol_int_callback(struct urb *urb)
47 struct symbol_private *priv = urb->context;
48 unsigned char *data = urb->transfer_buffer;
49 struct usb_serial_port *port = priv->port;
50 int status = urb->status;
51 struct tty_struct *tty;
62 /* this urb is terminated, clean up */
63 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
67 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
72 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
74 if (urb->actual_length > 1) {
75 data_length = urb->actual_length - 1;
78 * Data from the device comes with a 1 byte header:
80 * <size of data>data...
81 * This is real data to be sent to the tty layer
82 * we pretty much just ignore the size and send everything
83 * else to the tty layer.
85 tty = tty_port_tty_get(&port->port);
87 tty_insert_flip_string(tty, &data[1], data_length);
88 tty_flip_buffer_push(tty);
92 dev_dbg(&priv->udev->dev,
93 "Improper amount of data received from the device, "
94 "%d bytes", urb->actual_length);
98 spin_lock(&priv->lock);
100 /* Continue trying to always read if we should */
101 if (!priv->throttled) {
102 usb_fill_int_urb(priv->int_urb, priv->udev,
103 usb_rcvintpipe(priv->udev,
105 priv->int_buffer, priv->buffer_size,
106 symbol_int_callback, priv, priv->bInterval);
107 result = usb_submit_urb(priv->int_urb, GFP_ATOMIC);
110 "%s - failed resubmitting read urb, error %d\n",
113 priv->actually_throttled = true;
114 spin_unlock(&priv->lock);
117 static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)
119 struct symbol_private *priv = usb_get_serial_data(port->serial);
123 spin_lock_irqsave(&priv->lock, flags);
124 priv->throttled = false;
125 priv->actually_throttled = false;
127 spin_unlock_irqrestore(&priv->lock, flags);
129 /* Start reading from the device */
130 usb_fill_int_urb(priv->int_urb, priv->udev,
131 usb_rcvintpipe(priv->udev, priv->int_address),
132 priv->int_buffer, priv->buffer_size,
133 symbol_int_callback, priv, priv->bInterval);
134 result = usb_submit_urb(priv->int_urb, GFP_KERNEL);
137 "%s - failed resubmitting read urb, error %d\n",
142 static void symbol_close(struct usb_serial_port *port)
144 struct symbol_private *priv = usb_get_serial_data(port->serial);
146 /* shutdown our urbs */
147 usb_kill_urb(priv->int_urb);
150 static void symbol_throttle(struct tty_struct *tty)
152 struct usb_serial_port *port = tty->driver_data;
153 struct symbol_private *priv = usb_get_serial_data(port->serial);
155 spin_lock_irq(&priv->lock);
156 priv->throttled = true;
157 spin_unlock_irq(&priv->lock);
160 static void symbol_unthrottle(struct tty_struct *tty)
162 struct usb_serial_port *port = tty->driver_data;
163 struct symbol_private *priv = usb_get_serial_data(port->serial);
167 spin_lock_irq(&priv->lock);
168 priv->throttled = false;
169 was_throttled = priv->actually_throttled;
170 priv->actually_throttled = false;
171 spin_unlock_irq(&priv->lock);
174 result = usb_submit_urb(priv->int_urb, GFP_KERNEL);
177 "%s - failed submitting read urb, error %d\n",
182 static int symbol_startup(struct usb_serial *serial)
184 struct symbol_private *priv;
185 struct usb_host_interface *intf;
187 int retval = -ENOMEM;
188 bool int_in_found = false;
190 /* create our private serial structure */
191 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
193 dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
196 spin_lock_init(&priv->lock);
197 priv->serial = serial;
198 priv->port = serial->port[0];
199 priv->udev = serial->dev;
201 /* find our interrupt endpoint */
202 intf = serial->interface->altsetting;
203 for (i = 0; i < intf->desc.bNumEndpoints; ++i) {
204 struct usb_endpoint_descriptor *endpoint;
206 endpoint = &intf->endpoint[i].desc;
207 if (!usb_endpoint_is_int_in(endpoint))
210 priv->int_urb = usb_alloc_urb(0, GFP_KERNEL);
211 if (!priv->int_urb) {
212 dev_err(&priv->udev->dev, "out of memory\n");
216 priv->buffer_size = usb_endpoint_maxp(endpoint) * 2;
217 priv->int_buffer = kmalloc(priv->buffer_size, GFP_KERNEL);
218 if (!priv->int_buffer) {
219 dev_err(&priv->udev->dev, "out of memory\n");
223 priv->int_address = endpoint->bEndpointAddress;
224 priv->bInterval = endpoint->bInterval;
226 /* set up our int urb */
227 usb_fill_int_urb(priv->int_urb, priv->udev,
228 usb_rcvintpipe(priv->udev,
229 endpoint->bEndpointAddress),
230 priv->int_buffer, priv->buffer_size,
231 symbol_int_callback, priv, priv->bInterval);
238 dev_err(&priv->udev->dev,
239 "Error - the proper endpoints were not found!\n");
243 usb_set_serial_data(serial, priv);
247 usb_free_urb(priv->int_urb);
248 kfree(priv->int_buffer);
253 static void symbol_disconnect(struct usb_serial *serial)
255 struct symbol_private *priv = usb_get_serial_data(serial);
257 usb_kill_urb(priv->int_urb);
258 usb_free_urb(priv->int_urb);
261 static void symbol_release(struct usb_serial *serial)
263 struct symbol_private *priv = usb_get_serial_data(serial);
265 kfree(priv->int_buffer);
269 static struct usb_serial_driver symbol_device = {
271 .owner = THIS_MODULE,
274 .id_table = id_table,
276 .attach = symbol_startup,
278 .close = symbol_close,
279 .disconnect = symbol_disconnect,
280 .release = symbol_release,
281 .throttle = symbol_throttle,
282 .unthrottle = symbol_unthrottle,
285 static struct usb_serial_driver * const serial_drivers[] = {
289 module_usb_serial_driver(serial_drivers, id_table);
291 MODULE_LICENSE("GPL");