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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Opticon USB barcode to serial driver
4 *
5 * Copyright (C) 2011 - 2012 Johan Hovold <jhovold@gmail.com>
6 * Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
7 * Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
8 * Copyright (C) 2008 - 2009 Novell Inc.
9 */
10
11#include <linux/kernel.h>
12#include <linux/tty.h>
13#include <linux/tty_driver.h>
14#include <linux/slab.h>
15#include <linux/tty_flip.h>
16#include <linux/serial.h>
17#include <linux/module.h>
18#include <linux/usb.h>
19#include <linux/usb/serial.h>
20#include <linux/uaccess.h>
21
22#define CONTROL_RTS 0x02
23#define RESEND_CTS_STATE 0x03
24
25/* max number of write urbs in flight */
26#define URB_UPPER_LIMIT 8
27
28/* This driver works for the Opticon 1D barcode reader
29 * an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */
30#define DRIVER_DESC "Opticon USB barcode to serial driver (1D)"
31
32static const struct usb_device_id id_table[] = {
33 { USB_DEVICE(0x065a, 0x0009) },
34 { },
35};
36MODULE_DEVICE_TABLE(usb, id_table);
37
38/* This structure holds all of the individual device information */
39struct opticon_private {
40 spinlock_t lock; /* protects the following flags */
41 bool rts;
42 bool cts;
43 int outstanding_urbs;
44 int outstanding_bytes;
45
46 struct usb_anchor anchor;
47};
48
49
50static void opticon_process_data_packet(struct usb_serial_port *port,
51 const unsigned char *buf, size_t len)
52{
53 tty_insert_flip_string(&port->port, buf, len);
54 tty_flip_buffer_push(&port->port);
55}
56
57static void opticon_process_status_packet(struct usb_serial_port *port,
58 const unsigned char *buf, size_t len)
59{
60 struct opticon_private *priv = usb_get_serial_port_data(port);
61 unsigned long flags;
62
63 spin_lock_irqsave(&priv->lock, flags);
64 if (buf[0] == 0x00)
65 priv->cts = false;
66 else
67 priv->cts = true;
68 spin_unlock_irqrestore(&priv->lock, flags);
69}
70
71static void opticon_process_read_urb(struct urb *urb)
72{
73 struct usb_serial_port *port = urb->context;
74 const unsigned char *hdr = urb->transfer_buffer;
75 const unsigned char *data = hdr + 2;
76 size_t data_len = urb->actual_length - 2;
77
78 if (urb->actual_length <= 2) {
79 dev_dbg(&port->dev, "malformed packet received: %d bytes\n",
80 urb->actual_length);
81 return;
82 }
83 /*
84 * Data from the device comes with a 2 byte header:
85 *
86 * <0x00><0x00>data...
87 * This is real data to be sent to the tty layer
88 * <0x00><0x01>level
89 * This is a CTS level change, the third byte is the CTS
90 * value (0 for low, 1 for high).
91 */
92 if ((hdr[0] == 0x00) && (hdr[1] == 0x00)) {
93 opticon_process_data_packet(port, data, data_len);
94 } else if ((hdr[0] == 0x00) && (hdr[1] == 0x01)) {
95 opticon_process_status_packet(port, data, data_len);
96 } else {
97 dev_dbg(&port->dev, "unknown packet received: %02x %02x\n",
98 hdr[0], hdr[1]);
99 }
100}
101
102static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
103 u8 val)
104{
105 struct usb_serial *serial = port->serial;
106 int retval;
107 u8 *buffer;
108
109 buffer = kzalloc(1, GFP_KERNEL);
110 if (!buffer)
111 return -ENOMEM;
112
113 buffer[0] = val;
114 /* Send the message to the vendor control endpoint
115 * of the connected device */
116 retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
117 requesttype,
118 USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
119 0, 0, buffer, 1, USB_CTRL_SET_TIMEOUT);
120 kfree(buffer);
121
122 if (retval < 0)
123 return retval;
124
125 return 0;
126}
127
128static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
129{
130 struct opticon_private *priv = usb_get_serial_port_data(port);
131 unsigned long flags;
132 int res;
133
134 spin_lock_irqsave(&priv->lock, flags);
135 priv->rts = false;
136 spin_unlock_irqrestore(&priv->lock, flags);
137
138 /* Clear RTS line */
139 send_control_msg(port, CONTROL_RTS, 0);
140
141 /* clear the halt status of the endpoint */
142 usb_clear_halt(port->serial->dev, port->read_urb->pipe);
143
144 res = usb_serial_generic_open(tty, port);
145 if (res)
146 return res;
147
148 /* Request CTS line state, sometimes during opening the current
149 * CTS state can be missed. */
150 send_control_msg(port, RESEND_CTS_STATE, 1);
151
152 return res;
153}
154
155static void opticon_close(struct usb_serial_port *port)
156{
157 struct opticon_private *priv = usb_get_serial_port_data(port);
158
159 usb_kill_anchored_urbs(&priv->anchor);
160
161 usb_serial_generic_close(port);
162}
163
164static void opticon_write_control_callback(struct urb *urb)
165{
166 struct usb_serial_port *port = urb->context;
167 struct opticon_private *priv = usb_get_serial_port_data(port);
168 int status = urb->status;
169 unsigned long flags;
170
171 /* free up the transfer buffer, as usb_free_urb() does not do this */
172 kfree(urb->transfer_buffer);
173
174 /* setup packet may be set if we're using it for writing */
175 kfree(urb->setup_packet);
176
177 if (status)
178 dev_dbg(&port->dev,
179 "%s - non-zero urb status received: %d\n",
180 __func__, status);
181
182 spin_lock_irqsave(&priv->lock, flags);
183 --priv->outstanding_urbs;
184 priv->outstanding_bytes -= urb->transfer_buffer_length;
185 spin_unlock_irqrestore(&priv->lock, flags);
186
187 usb_serial_port_softint(port);
188}
189
190static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
191 const unsigned char *buf, int count)
192{
193 struct opticon_private *priv = usb_get_serial_port_data(port);
194 struct usb_serial *serial = port->serial;
195 struct urb *urb;
196 unsigned char *buffer;
197 unsigned long flags;
198 struct usb_ctrlrequest *dr;
199 int ret = -ENOMEM;
200
201 spin_lock_irqsave(&priv->lock, flags);
202 if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
203 spin_unlock_irqrestore(&priv->lock, flags);
204 dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
205 return 0;
206 }
207 priv->outstanding_urbs++;
208 priv->outstanding_bytes += count;
209 spin_unlock_irqrestore(&priv->lock, flags);
210
211 buffer = kmemdup(buf, count, GFP_ATOMIC);
212 if (!buffer)
213 goto error_no_buffer;
214
215 urb = usb_alloc_urb(0, GFP_ATOMIC);
216 if (!urb)
217 goto error_no_urb;
218
219 usb_serial_debug_data(&port->dev, __func__, count, buffer);
220
221 /* The connected devices do not have a bulk write endpoint,
222 * to transmit data to de barcode device the control endpoint is used */
223 dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
224 if (!dr)
225 goto error_no_dr;
226
227 dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
228 dr->bRequest = 0x01;
229 dr->wValue = 0;
230 dr->wIndex = 0;
231 dr->wLength = cpu_to_le16(count);
232
233 usb_fill_control_urb(urb, serial->dev,
234 usb_sndctrlpipe(serial->dev, 0),
235 (unsigned char *)dr, buffer, count,
236 opticon_write_control_callback, port);
237
238 usb_anchor_urb(urb, &priv->anchor);
239
240 /* send it down the pipe */
241 ret = usb_submit_urb(urb, GFP_ATOMIC);
242 if (ret) {
243 dev_err(&port->dev, "failed to submit write urb: %d\n", ret);
244 usb_unanchor_urb(urb);
245 goto error;
246 }
247
248 /* we are done with this urb, so let the host driver
249 * really free it when it is finished with it */
250 usb_free_urb(urb);
251
252 return count;
253error:
254 kfree(dr);
255error_no_dr:
256 usb_free_urb(urb);
257error_no_urb:
258 kfree(buffer);
259error_no_buffer:
260 spin_lock_irqsave(&priv->lock, flags);
261 --priv->outstanding_urbs;
262 priv->outstanding_bytes -= count;
263 spin_unlock_irqrestore(&priv->lock, flags);
264
265 return ret;
266}
267
268static unsigned int opticon_write_room(struct tty_struct *tty)
269{
270 struct usb_serial_port *port = tty->driver_data;
271 struct opticon_private *priv = usb_get_serial_port_data(port);
272 unsigned long flags;
273
274 /*
275 * We really can take almost anything the user throws at us
276 * but let's pick a nice big number to tell the tty
277 * layer that we have lots of free space, unless we don't.
278 */
279 spin_lock_irqsave(&priv->lock, flags);
280 if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
281 spin_unlock_irqrestore(&priv->lock, flags);
282 dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
283 return 0;
284 }
285 spin_unlock_irqrestore(&priv->lock, flags);
286
287 return 2048;
288}
289
290static unsigned int opticon_chars_in_buffer(struct tty_struct *tty)
291{
292 struct usb_serial_port *port = tty->driver_data;
293 struct opticon_private *priv = usb_get_serial_port_data(port);
294 unsigned long flags;
295 unsigned int count;
296
297 spin_lock_irqsave(&priv->lock, flags);
298 count = priv->outstanding_bytes;
299 spin_unlock_irqrestore(&priv->lock, flags);
300
301 return count;
302}
303
304static int opticon_tiocmget(struct tty_struct *tty)
305{
306 struct usb_serial_port *port = tty->driver_data;
307 struct opticon_private *priv = usb_get_serial_port_data(port);
308 unsigned long flags;
309 int result = 0;
310
311 spin_lock_irqsave(&priv->lock, flags);
312 if (priv->rts)
313 result |= TIOCM_RTS;
314 if (priv->cts)
315 result |= TIOCM_CTS;
316 spin_unlock_irqrestore(&priv->lock, flags);
317
318 dev_dbg(&port->dev, "%s - %x\n", __func__, result);
319 return result;
320}
321
322static int opticon_tiocmset(struct tty_struct *tty,
323 unsigned int set, unsigned int clear)
324{
325 struct usb_serial_port *port = tty->driver_data;
326 struct opticon_private *priv = usb_get_serial_port_data(port);
327 unsigned long flags;
328 bool rts;
329 bool changed = false;
330 int ret;
331
332 /* We only support RTS so we only handle that */
333 spin_lock_irqsave(&priv->lock, flags);
334
335 rts = priv->rts;
336 if (set & TIOCM_RTS)
337 priv->rts = true;
338 if (clear & TIOCM_RTS)
339 priv->rts = false;
340 changed = rts ^ priv->rts;
341 spin_unlock_irqrestore(&priv->lock, flags);
342
343 if (!changed)
344 return 0;
345
346 ret = send_control_msg(port, CONTROL_RTS, !rts);
347 if (ret)
348 return usb_translate_errors(ret);
349
350 return 0;
351}
352
353static int opticon_port_probe(struct usb_serial_port *port)
354{
355 struct opticon_private *priv;
356
357 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
358 if (!priv)
359 return -ENOMEM;
360
361 spin_lock_init(&priv->lock);
362 init_usb_anchor(&priv->anchor);
363
364 usb_set_serial_port_data(port, priv);
365
366 return 0;
367}
368
369static void opticon_port_remove(struct usb_serial_port *port)
370{
371 struct opticon_private *priv = usb_get_serial_port_data(port);
372
373 kfree(priv);
374}
375
376static struct usb_serial_driver opticon_device = {
377 .driver = {
378 .owner = THIS_MODULE,
379 .name = "opticon",
380 },
381 .id_table = id_table,
382 .num_ports = 1,
383 .num_bulk_in = 1,
384 .bulk_in_size = 256,
385 .port_probe = opticon_port_probe,
386 .port_remove = opticon_port_remove,
387 .open = opticon_open,
388 .close = opticon_close,
389 .write = opticon_write,
390 .write_room = opticon_write_room,
391 .chars_in_buffer = opticon_chars_in_buffer,
392 .throttle = usb_serial_generic_throttle,
393 .unthrottle = usb_serial_generic_unthrottle,
394 .tiocmget = opticon_tiocmget,
395 .tiocmset = opticon_tiocmset,
396 .process_read_urb = opticon_process_read_urb,
397};
398
399static struct usb_serial_driver * const serial_drivers[] = {
400 &opticon_device, NULL
401};
402
403module_usb_serial_driver(serial_drivers, id_table);
404
405MODULE_DESCRIPTION(DRIVER_DESC);
406MODULE_LICENSE("GPL v2");
1/*
2 * Opticon USB barcode to serial driver
3 *
4 * Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
5 * Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
6 * Copyright (C) 2008 - 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/init.h>
15#include <linux/tty.h>
16#include <linux/tty_driver.h>
17#include <linux/slab.h>
18#include <linux/tty_flip.h>
19#include <linux/serial.h>
20#include <linux/module.h>
21#include <linux/usb.h>
22#include <linux/usb/serial.h>
23#include <linux/uaccess.h>
24
25#define CONTROL_RTS 0x02
26#define RESEND_CTS_STATE 0x03
27
28/* max number of write urbs in flight */
29#define URB_UPPER_LIMIT 8
30
31/* This driver works for the Opticon 1D barcode reader
32 * an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */
33#define DRIVER_DESC "Opticon USB barcode to serial driver (1D)"
34
35static bool debug;
36
37static const struct usb_device_id id_table[] = {
38 { USB_DEVICE(0x065a, 0x0009) },
39 { },
40};
41MODULE_DEVICE_TABLE(usb, id_table);
42
43/* This structure holds all of the individual device information */
44struct opticon_private {
45 struct usb_device *udev;
46 struct usb_serial *serial;
47 struct usb_serial_port *port;
48 unsigned char *bulk_in_buffer;
49 struct urb *bulk_read_urb;
50 int buffer_size;
51 u8 bulk_address;
52 spinlock_t lock; /* protects the following flags */
53 bool throttled;
54 bool actually_throttled;
55 bool rts;
56 bool cts;
57 int outstanding_urbs;
58};
59
60
61
62static void opticon_read_bulk_callback(struct urb *urb)
63{
64 struct opticon_private *priv = urb->context;
65 unsigned char *data = urb->transfer_buffer;
66 struct usb_serial_port *port = priv->port;
67 int status = urb->status;
68 struct tty_struct *tty;
69 int result;
70 int data_length;
71 unsigned long flags;
72
73 switch (status) {
74 case 0:
75 /* success */
76 break;
77 case -ECONNRESET:
78 case -ENOENT:
79 case -ESHUTDOWN:
80 /* this urb is terminated, clean up */
81 dbg("%s - urb shutting down with status: %d",
82 __func__, status);
83 return;
84 default:
85 dbg("%s - nonzero urb status received: %d",
86 __func__, status);
87 goto exit;
88 }
89
90 usb_serial_debug_data(debug, &port->dev, __func__, urb->actual_length,
91 data);
92
93 if (urb->actual_length > 2) {
94 data_length = urb->actual_length - 2;
95
96 /*
97 * Data from the device comes with a 2 byte header:
98 *
99 * <0x00><0x00>data...
100 * This is real data to be sent to the tty layer
101 * <0x00><0x01)level
102 * This is a CTS level change, the third byte is the CTS
103 * value (0 for low, 1 for high).
104 */
105 if ((data[0] == 0x00) && (data[1] == 0x00)) {
106 /* real data, send it to the tty layer */
107 tty = tty_port_tty_get(&port->port);
108 if (tty) {
109 tty_insert_flip_string(tty, data + 2,
110 data_length);
111 tty_flip_buffer_push(tty);
112 tty_kref_put(tty);
113 }
114 } else {
115 if ((data[0] == 0x00) && (data[1] == 0x01)) {
116 spin_lock_irqsave(&priv->lock, flags);
117 /* CTS status information package */
118 if (data[2] == 0x00)
119 priv->cts = false;
120 else
121 priv->cts = true;
122 spin_unlock_irqrestore(&priv->lock, flags);
123 } else {
124 dev_dbg(&priv->udev->dev,
125 "Unknown data packet received from the device:"
126 " %2x %2x\n",
127 data[0], data[1]);
128 }
129 }
130 } else {
131 dev_dbg(&priv->udev->dev,
132 "Improper amount of data received from the device, "
133 "%d bytes", urb->actual_length);
134 }
135
136exit:
137 spin_lock(&priv->lock);
138
139 /* Continue trying to always read if we should */
140 if (!priv->throttled) {
141 usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
142 usb_rcvbulkpipe(priv->udev,
143 priv->bulk_address),
144 priv->bulk_in_buffer, priv->buffer_size,
145 opticon_read_bulk_callback, priv);
146 result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
147 if (result)
148 dev_err(&port->dev,
149 "%s - failed resubmitting read urb, error %d\n",
150 __func__, result);
151 } else
152 priv->actually_throttled = true;
153 spin_unlock(&priv->lock);
154}
155
156static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
157 u8 val)
158{
159 struct usb_serial *serial = port->serial;
160 int retval;
161 u8 buffer[2];
162
163 buffer[0] = val;
164 /* Send the message to the vendor control endpoint
165 * of the connected device */
166 retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
167 requesttype,
168 USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
169 0, 0, buffer, 1, 0);
170
171 return retval;
172}
173
174static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
175{
176 struct opticon_private *priv = usb_get_serial_data(port->serial);
177 unsigned long flags;
178 int result = 0;
179
180 spin_lock_irqsave(&priv->lock, flags);
181 priv->throttled = false;
182 priv->actually_throttled = false;
183 priv->port = port;
184 priv->rts = false;
185 spin_unlock_irqrestore(&priv->lock, flags);
186
187 /* Clear RTS line */
188 send_control_msg(port, CONTROL_RTS, 0);
189
190 /* Setup the read URB and start reading from the device */
191 usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
192 usb_rcvbulkpipe(priv->udev,
193 priv->bulk_address),
194 priv->bulk_in_buffer, priv->buffer_size,
195 opticon_read_bulk_callback, priv);
196
197 /* clear the halt status of the enpoint */
198 usb_clear_halt(priv->udev, priv->bulk_read_urb->pipe);
199
200 result = usb_submit_urb(priv->bulk_read_urb, GFP_KERNEL);
201 if (result)
202 dev_err(&port->dev,
203 "%s - failed resubmitting read urb, error %d\n",
204 __func__, result);
205 /* Request CTS line state, sometimes during opening the current
206 * CTS state can be missed. */
207 send_control_msg(port, RESEND_CTS_STATE, 1);
208 return result;
209}
210
211static void opticon_close(struct usb_serial_port *port)
212{
213 struct opticon_private *priv = usb_get_serial_data(port->serial);
214
215 /* shutdown our urbs */
216 usb_kill_urb(priv->bulk_read_urb);
217}
218
219static void opticon_write_control_callback(struct urb *urb)
220{
221 struct opticon_private *priv = urb->context;
222 int status = urb->status;
223 unsigned long flags;
224
225 /* free up the transfer buffer, as usb_free_urb() does not do this */
226 kfree(urb->transfer_buffer);
227
228 /* setup packet may be set if we're using it for writing */
229 kfree(urb->setup_packet);
230
231 if (status)
232 dbg("%s - nonzero write bulk status received: %d",
233 __func__, status);
234
235 spin_lock_irqsave(&priv->lock, flags);
236 --priv->outstanding_urbs;
237 spin_unlock_irqrestore(&priv->lock, flags);
238
239 usb_serial_port_softint(priv->port);
240}
241
242static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
243 const unsigned char *buf, int count)
244{
245 struct opticon_private *priv = usb_get_serial_data(port->serial);
246 struct usb_serial *serial = port->serial;
247 struct urb *urb;
248 unsigned char *buffer;
249 unsigned long flags;
250 int status;
251 struct usb_ctrlrequest *dr;
252
253 spin_lock_irqsave(&priv->lock, flags);
254 if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
255 spin_unlock_irqrestore(&priv->lock, flags);
256 dbg("%s - write limit hit", __func__);
257 return 0;
258 }
259 priv->outstanding_urbs++;
260 spin_unlock_irqrestore(&priv->lock, flags);
261
262 buffer = kmalloc(count, GFP_ATOMIC);
263 if (!buffer) {
264 dev_err(&port->dev, "out of memory\n");
265 count = -ENOMEM;
266
267 goto error_no_buffer;
268 }
269
270 urb = usb_alloc_urb(0, GFP_ATOMIC);
271 if (!urb) {
272 dev_err(&port->dev, "no more free urbs\n");
273 count = -ENOMEM;
274 goto error_no_urb;
275 }
276
277 memcpy(buffer, buf, count);
278
279 usb_serial_debug_data(debug, &port->dev, __func__, count, buffer);
280
281 /* The conncected devices do not have a bulk write endpoint,
282 * to transmit data to de barcode device the control endpoint is used */
283 dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO);
284 if (!dr) {
285 dev_err(&port->dev, "out of memory\n");
286 count = -ENOMEM;
287 goto error;
288 }
289
290 dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
291 dr->bRequest = 0x01;
292 dr->wValue = 0;
293 dr->wIndex = 0;
294 dr->wLength = cpu_to_le16(count);
295
296 usb_fill_control_urb(urb, serial->dev,
297 usb_sndctrlpipe(serial->dev, 0),
298 (unsigned char *)dr, buffer, count,
299 opticon_write_control_callback, priv);
300
301 /* send it down the pipe */
302 status = usb_submit_urb(urb, GFP_ATOMIC);
303 if (status) {
304 dev_err(&port->dev,
305 "%s - usb_submit_urb(write endpoint) failed status = %d\n",
306 __func__, status);
307 count = status;
308 goto error;
309 }
310
311 /* we are done with this urb, so let the host driver
312 * really free it when it is finished with it */
313 usb_free_urb(urb);
314
315 return count;
316error:
317 usb_free_urb(urb);
318error_no_urb:
319 kfree(buffer);
320error_no_buffer:
321 spin_lock_irqsave(&priv->lock, flags);
322 --priv->outstanding_urbs;
323 spin_unlock_irqrestore(&priv->lock, flags);
324 return count;
325}
326
327static int opticon_write_room(struct tty_struct *tty)
328{
329 struct usb_serial_port *port = tty->driver_data;
330 struct opticon_private *priv = usb_get_serial_data(port->serial);
331 unsigned long flags;
332
333 /*
334 * We really can take almost anything the user throws at us
335 * but let's pick a nice big number to tell the tty
336 * layer that we have lots of free space, unless we don't.
337 */
338 spin_lock_irqsave(&priv->lock, flags);
339 if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
340 spin_unlock_irqrestore(&priv->lock, flags);
341 dbg("%s - write limit hit", __func__);
342 return 0;
343 }
344 spin_unlock_irqrestore(&priv->lock, flags);
345
346 return 2048;
347}
348
349static void opticon_throttle(struct tty_struct *tty)
350{
351 struct usb_serial_port *port = tty->driver_data;
352 struct opticon_private *priv = usb_get_serial_data(port->serial);
353 unsigned long flags;
354
355 spin_lock_irqsave(&priv->lock, flags);
356 priv->throttled = true;
357 spin_unlock_irqrestore(&priv->lock, flags);
358}
359
360
361static void opticon_unthrottle(struct tty_struct *tty)
362{
363 struct usb_serial_port *port = tty->driver_data;
364 struct opticon_private *priv = usb_get_serial_data(port->serial);
365 unsigned long flags;
366 int result, was_throttled;
367
368 spin_lock_irqsave(&priv->lock, flags);
369 priv->throttled = false;
370 was_throttled = priv->actually_throttled;
371 priv->actually_throttled = false;
372 spin_unlock_irqrestore(&priv->lock, flags);
373
374 if (was_throttled) {
375 result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
376 if (result)
377 dev_err(&port->dev,
378 "%s - failed submitting read urb, error %d\n",
379 __func__, result);
380 }
381}
382
383static int opticon_tiocmget(struct tty_struct *tty)
384{
385 struct usb_serial_port *port = tty->driver_data;
386 struct opticon_private *priv = usb_get_serial_data(port->serial);
387 unsigned long flags;
388 int result = 0;
389
390 spin_lock_irqsave(&priv->lock, flags);
391 if (priv->rts)
392 result |= TIOCM_RTS;
393 if (priv->cts)
394 result |= TIOCM_CTS;
395 spin_unlock_irqrestore(&priv->lock, flags);
396
397 dbg("%s - %x", __func__, result);
398 return result;
399}
400
401static int opticon_tiocmset(struct tty_struct *tty,
402 unsigned int set, unsigned int clear)
403{
404 struct usb_serial_port *port = tty->driver_data;
405 struct usb_serial *serial = port->serial;
406 struct opticon_private *priv = usb_get_serial_data(port->serial);
407 unsigned long flags;
408 bool rts;
409 bool changed = false;
410 int ret;
411
412 /* We only support RTS so we only handle that */
413 spin_lock_irqsave(&priv->lock, flags);
414
415 rts = priv->rts;
416 if (set & TIOCM_RTS)
417 priv->rts = true;
418 if (clear & TIOCM_RTS)
419 priv->rts = false;
420 changed = rts ^ priv->rts;
421 spin_unlock_irqrestore(&priv->lock, flags);
422
423 if (!changed)
424 return 0;
425
426 /* Send the new RTS state to the connected device */
427 mutex_lock(&serial->disc_mutex);
428 if (!serial->disconnected)
429 ret = send_control_msg(port, CONTROL_RTS, !rts);
430 else
431 ret = -ENODEV;
432 mutex_unlock(&serial->disc_mutex);
433
434 return ret;
435}
436
437static int get_serial_info(struct opticon_private *priv,
438 struct serial_struct __user *serial)
439{
440 struct serial_struct tmp;
441
442 if (!serial)
443 return -EFAULT;
444
445 memset(&tmp, 0x00, sizeof(tmp));
446
447 /* fake emulate a 16550 uart to make userspace code happy */
448 tmp.type = PORT_16550A;
449 tmp.line = priv->serial->minor;
450 tmp.port = 0;
451 tmp.irq = 0;
452 tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
453 tmp.xmit_fifo_size = 1024;
454 tmp.baud_base = 9600;
455 tmp.close_delay = 5*HZ;
456 tmp.closing_wait = 30*HZ;
457
458 if (copy_to_user(serial, &tmp, sizeof(*serial)))
459 return -EFAULT;
460 return 0;
461}
462
463static int opticon_ioctl(struct tty_struct *tty,
464 unsigned int cmd, unsigned long arg)
465{
466 struct usb_serial_port *port = tty->driver_data;
467 struct opticon_private *priv = usb_get_serial_data(port->serial);
468
469 dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
470
471 switch (cmd) {
472 case TIOCGSERIAL:
473 return get_serial_info(priv,
474 (struct serial_struct __user *)arg);
475 }
476
477 return -ENOIOCTLCMD;
478}
479
480static int opticon_startup(struct usb_serial *serial)
481{
482 struct opticon_private *priv;
483 struct usb_host_interface *intf;
484 int i;
485 int retval = -ENOMEM;
486 bool bulk_in_found = false;
487
488 /* create our private serial structure */
489 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
490 if (priv == NULL) {
491 dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
492 return -ENOMEM;
493 }
494 spin_lock_init(&priv->lock);
495 priv->serial = serial;
496 priv->port = serial->port[0];
497 priv->udev = serial->dev;
498 priv->outstanding_urbs = 0; /* Init the outstanding urbs */
499
500 /* find our bulk endpoint */
501 intf = serial->interface->altsetting;
502 for (i = 0; i < intf->desc.bNumEndpoints; ++i) {
503 struct usb_endpoint_descriptor *endpoint;
504
505 endpoint = &intf->endpoint[i].desc;
506 if (!usb_endpoint_is_bulk_in(endpoint))
507 continue;
508
509 priv->bulk_read_urb = usb_alloc_urb(0, GFP_KERNEL);
510 if (!priv->bulk_read_urb) {
511 dev_err(&priv->udev->dev, "out of memory\n");
512 goto error;
513 }
514
515 priv->buffer_size = usb_endpoint_maxp(endpoint) * 2;
516 priv->bulk_in_buffer = kmalloc(priv->buffer_size, GFP_KERNEL);
517 if (!priv->bulk_in_buffer) {
518 dev_err(&priv->udev->dev, "out of memory\n");
519 goto error;
520 }
521
522 priv->bulk_address = endpoint->bEndpointAddress;
523
524 bulk_in_found = true;
525 break;
526 }
527
528 if (!bulk_in_found) {
529 dev_err(&priv->udev->dev,
530 "Error - the proper endpoints were not found!\n");
531 goto error;
532 }
533
534 usb_set_serial_data(serial, priv);
535 return 0;
536
537error:
538 usb_free_urb(priv->bulk_read_urb);
539 kfree(priv->bulk_in_buffer);
540 kfree(priv);
541 return retval;
542}
543
544static void opticon_disconnect(struct usb_serial *serial)
545{
546 struct opticon_private *priv = usb_get_serial_data(serial);
547
548 usb_kill_urb(priv->bulk_read_urb);
549 usb_free_urb(priv->bulk_read_urb);
550}
551
552static void opticon_release(struct usb_serial *serial)
553{
554 struct opticon_private *priv = usb_get_serial_data(serial);
555
556 kfree(priv->bulk_in_buffer);
557 kfree(priv);
558}
559
560static int opticon_suspend(struct usb_serial *serial, pm_message_t message)
561{
562 struct opticon_private *priv = usb_get_serial_data(serial);
563
564 usb_kill_urb(priv->bulk_read_urb);
565 return 0;
566}
567
568static int opticon_resume(struct usb_serial *serial)
569{
570 struct opticon_private *priv = usb_get_serial_data(serial);
571 struct usb_serial_port *port = serial->port[0];
572 int result;
573
574 mutex_lock(&port->port.mutex);
575 /* This is protected by the port mutex against close/open */
576 if (test_bit(ASYNCB_INITIALIZED, &port->port.flags))
577 result = usb_submit_urb(priv->bulk_read_urb, GFP_NOIO);
578 else
579 result = 0;
580 mutex_unlock(&port->port.mutex);
581 return result;
582}
583
584static struct usb_serial_driver opticon_device = {
585 .driver = {
586 .owner = THIS_MODULE,
587 .name = "opticon",
588 },
589 .id_table = id_table,
590 .num_ports = 1,
591 .attach = opticon_startup,
592 .open = opticon_open,
593 .close = opticon_close,
594 .write = opticon_write,
595 .write_room = opticon_write_room,
596 .disconnect = opticon_disconnect,
597 .release = opticon_release,
598 .throttle = opticon_throttle,
599 .unthrottle = opticon_unthrottle,
600 .ioctl = opticon_ioctl,
601 .tiocmget = opticon_tiocmget,
602 .tiocmset = opticon_tiocmset,
603 .suspend = opticon_suspend,
604 .resume = opticon_resume,
605};
606
607static struct usb_serial_driver * const serial_drivers[] = {
608 &opticon_device, NULL
609};
610
611module_usb_serial_driver(serial_drivers, id_table);
612
613MODULE_DESCRIPTION(DRIVER_DESC);
614MODULE_LICENSE("GPL");
615
616module_param(debug, bool, S_IRUGO | S_IWUSR);
617MODULE_PARM_DESC(debug, "Debug enabled or not");