blob: cea326f1f105535886de22ab8353c850929fe43b [file] [log] [blame]
Greg Kroah-Hartman57262b82008-11-03 13:27:03 -08001/*
2 * Opticon USB barcode to serial driver
3 *
4 * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>
5 * Copyright (C) 2008 Novell Inc.
6 *
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.
10 */
11
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/tty.h>
15#include <linux/tty_driver.h>
16#include <linux/tty_flip.h>
17#include <linux/module.h>
18#include <linux/usb.h>
19#include <linux/usb/serial.h>
20#include <linux/uaccess.h>
21
22static int debug;
23
24static struct usb_device_id id_table[] = {
25 { USB_DEVICE(0x065a, 0x0009) },
26 { },
27};
28MODULE_DEVICE_TABLE(usb, id_table);
29
30/* This structure holds all of the individual device information */
31struct opticon_private {
32 struct usb_device *udev;
33 struct usb_serial *serial;
34 struct usb_serial_port *port;
35 unsigned char *bulk_in_buffer;
36 struct urb *bulk_read_urb;
37 int buffer_size;
38 u8 bulk_address;
39 spinlock_t lock; /* protects the following flags */
40 bool throttled;
41 bool actually_throttled;
42 bool rts;
43};
44
45static void opticon_bulk_callback(struct urb *urb)
46{
47 struct opticon_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;
52 int result;
53 int available_room = 0;
54 int data_length;
55
56 dbg("%s - port %d", __func__, port->number);
57
58 switch (status) {
59 case 0:
60 /* success */
61 break;
62 case -ECONNRESET:
63 case -ENOENT:
64 case -ESHUTDOWN:
65 /* this urb is terminated, clean up */
66 dbg("%s - urb shutting down with status: %d",
67 __func__, status);
68 return;
69 default:
70 dbg("%s - nonzero urb status received: %d",
71 __func__, status);
72 goto exit;
73 }
74
75 usb_serial_debug_data(debug, &port->dev, __func__, urb->actual_length,
76 data);
77
78 if (urb->actual_length > 2) {
79 data_length = urb->actual_length - 2;
80
81 /*
82 * Data from the device comes with a 2 byte header:
83 *
84 * <0x00><0x00>data...
85 * This is real data to be sent to the tty layer
86 * <0x00><0x01)level
87 * This is a RTS level change, the third byte is the RTS
88 * value (0 for low, 1 for high).
89 */
90 if ((data[0] == 0x00) && (data[1] == 0x00)) {
91 /* real data, send it to the tty layer */
92 tty = tty_port_tty_get(&port->port);
93 if (tty) {
94 available_room = tty_buffer_request_room(tty,
95 data_length);
96 if (available_room) {
97 tty_insert_flip_string(tty, data,
98 available_room);
99 tty_flip_buffer_push(tty);
100 }
101 tty_kref_put(tty);
102 }
103 } else {
104 if ((data[0] == 0x00) && (data[1] == 0x01)) {
105 if (data[2] == 0x00)
106 priv->rts = false;
107 else
108 priv->rts = true;
109 /* FIXME change the RTS level */
110 } else {
111 dev_dbg(&priv->udev->dev,
112 "Unknown data packet received from the device:"
113 " %2x %2x\n",
114 data[0], data[1]);
115 }
116 }
117 } else {
118 dev_dbg(&priv->udev->dev,
119 "Improper ammount of data received from the device, "
120 "%d bytes", urb->actual_length);
121 }
122
123exit:
124 spin_lock(&priv->lock);
125
126 /* Continue trying to always read if we should */
127 if (!priv->throttled) {
128 usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
129 usb_rcvbulkpipe(priv->udev,
130 priv->bulk_address),
131 priv->bulk_in_buffer, priv->buffer_size,
132 opticon_bulk_callback, priv);
133 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
134 if (result)
135 dev_err(&port->dev,
136 "%s - failed resubmitting read urb, error %d\n",
137 __func__, result);
138 } else
139 priv->actually_throttled = true;
140 spin_unlock(&priv->lock);
141}
142
143static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port,
144 struct file *filp)
145{
146 struct opticon_private *priv = usb_get_serial_data(port->serial);
147 unsigned long flags;
148 int result = 0;
149
150 dbg("%s - port %d", __func__, port->number);
151
152 spin_lock_irqsave(&priv->lock, flags);
153 priv->throttled = false;
154 priv->actually_throttled = false;
155 priv->port = port;
156 spin_unlock_irqrestore(&priv->lock, flags);
157
158 /*
159 * Force low_latency on so that our tty_push actually forces the data
160 * through, otherwise it is scheduled, and with high data rates (like
161 * with OHCI) data can get lost.
162 */
163 if (tty)
164 tty->low_latency = 1;
165
166 /* Start reading from the device */
167 usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
168 usb_rcvbulkpipe(priv->udev,
169 priv->bulk_address),
170 priv->bulk_in_buffer, priv->buffer_size,
171 opticon_bulk_callback, priv);
172 result = usb_submit_urb(priv->bulk_read_urb, GFP_KERNEL);
173 if (result)
174 dev_err(&port->dev,
175 "%s - failed resubmitting read urb, error %d\n",
176 __func__, result);
177 return result;
178}
179
180static void opticon_close(struct tty_struct *tty, struct usb_serial_port *port,
181 struct file *filp)
182{
183 struct opticon_private *priv = usb_get_serial_data(port->serial);
184
185 dbg("%s - port %d", __func__, port->number);
186
187 /* shutdown our urbs */
188 usb_kill_urb(priv->bulk_read_urb);
189}
190
191static void opticon_throttle(struct tty_struct *tty)
192{
193 struct usb_serial_port *port = tty->driver_data;
194 struct opticon_private *priv = usb_get_serial_data(port->serial);
195 unsigned long flags;
196
197 dbg("%s - port %d", __func__, port->number);
198 spin_lock_irqsave(&priv->lock, flags);
199 priv->throttled = true;
200 spin_unlock_irqrestore(&priv->lock, flags);
201}
202
203
204static void opticon_unthrottle(struct tty_struct *tty)
205{
206 struct usb_serial_port *port = tty->driver_data;
207 struct opticon_private *priv = usb_get_serial_data(port->serial);
208 unsigned long flags;
209 int result;
210
211 dbg("%s - port %d", __func__, port->number);
212
213 spin_lock_irqsave(&priv->lock, flags);
214 priv->throttled = false;
215 priv->actually_throttled = false;
216 spin_unlock_irqrestore(&priv->lock, flags);
217
218 priv->bulk_read_urb->dev = port->serial->dev;
219 result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
220 if (result)
221 dev_err(&port->dev,
222 "%s - failed submitting read urb, error %d\n",
223 __func__, result);
224}
225
226static int opticon_startup(struct usb_serial *serial)
227{
228 struct opticon_private *priv;
229 struct usb_host_interface *intf;
230 int i;
231 int retval = -ENOMEM;
232 bool bulk_in_found = false;
233
234 /* create our private serial structure */
235 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
236 if (priv == NULL) {
237 dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
238 return -ENOMEM;
239 }
240 spin_lock_init(&priv->lock);
241 priv->serial = serial;
242 priv->port = serial->port[0];
243 priv->udev = serial->dev;
244
245 /* find our bulk endpoint */
246 intf = serial->interface->altsetting;
247 for (i = 0; i < intf->desc.bNumEndpoints; ++i) {
248 struct usb_endpoint_descriptor *endpoint;
249
250 endpoint = &intf->endpoint[i].desc;
251 if (!usb_endpoint_is_bulk_in(endpoint))
252 continue;
253
254 priv->bulk_read_urb = usb_alloc_urb(0, GFP_KERNEL);
255 if (!priv->bulk_read_urb) {
256 dev_err(&priv->udev->dev, "out of memory\n");
257 goto error;
258 }
259
260 priv->buffer_size = le16_to_cpu(endpoint->wMaxPacketSize) * 2;
261 priv->bulk_in_buffer = kmalloc(priv->buffer_size, GFP_KERNEL);
262 if (!priv->bulk_in_buffer) {
263 dev_err(&priv->udev->dev, "out of memory\n");
264 goto error;
265 }
266
267 priv->bulk_address = endpoint->bEndpointAddress;
268
269 /* set up our bulk urb */
270 usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
271 usb_rcvbulkpipe(priv->udev,
272 endpoint->bEndpointAddress),
273 priv->bulk_in_buffer, priv->buffer_size,
274 opticon_bulk_callback, priv);
275
276 bulk_in_found = true;
277 break;
278 }
279
280 if (!bulk_in_found) {
281 dev_err(&priv->udev->dev,
282 "Error - the proper endpoints were not found!\n");
283 goto error;
284 }
285
286 usb_set_serial_data(serial, priv);
287 return 0;
288
289error:
290 usb_free_urb(priv->bulk_read_urb);
291 kfree(priv->bulk_in_buffer);
292 kfree(priv);
293 return retval;
294}
295
296static void opticon_shutdown(struct usb_serial *serial)
297{
298 struct opticon_private *priv = usb_get_serial_data(serial);
299
300 dbg("%s", __func__);
301
302 usb_kill_urb(priv->bulk_read_urb);
303 usb_free_urb(priv->bulk_read_urb);
304 kfree(priv->bulk_in_buffer);
305 kfree(priv);
306 usb_set_serial_data(serial, NULL);
307}
308
309
310static struct usb_driver opticon_driver = {
311 .name = "opticon",
312 .probe = usb_serial_probe,
313 .disconnect = usb_serial_disconnect,
314 .id_table = id_table,
315 .no_dynamic_id = 1,
316};
317
318static struct usb_serial_driver opticon_device = {
319 .driver = {
320 .owner = THIS_MODULE,
321 .name = "opticon",
322 },
323 .id_table = id_table,
324 .usb_driver = &opticon_driver,
325 .num_ports = 1,
326 .attach = opticon_startup,
327 .open = opticon_open,
328 .close = opticon_close,
329 .shutdown = opticon_shutdown,
330 .throttle = opticon_throttle,
331 .unthrottle = opticon_unthrottle,
332};
333
334static int __init opticon_init(void)
335{
336 int retval;
337
338 retval = usb_serial_register(&opticon_device);
339 if (retval)
340 return retval;
341 retval = usb_register(&opticon_driver);
342 if (retval)
343 usb_serial_deregister(&opticon_device);
344 return retval;
345}
346
347static void __exit opticon_exit(void)
348{
349 usb_deregister(&opticon_driver);
350 usb_serial_deregister(&opticon_device);
351}
352
353module_init(opticon_init);
354module_exit(opticon_exit);
355MODULE_LICENSE("GPL");
356
357module_param(debug, bool, S_IRUGO | S_IWUSR);
358MODULE_PARM_DESC(debug, "Debug enabled or not");