2 * Opticon USB barcode to serial driver
4 * Copyright (C) 2011 - 2012 Johan Hovold <jhovold@gmail.com>
5 * Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
6 * Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (C) 2008 - 2009 Novell Inc.
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License version
11 * 2 as published by the Free Software Foundation.
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/tty.h>
17 #include <linux/tty_driver.h>
18 #include <linux/slab.h>
19 #include <linux/tty_flip.h>
20 #include <linux/serial.h>
21 #include <linux/module.h>
22 #include <linux/usb.h>
23 #include <linux/usb/serial.h>
24 #include <linux/uaccess.h>
26 #define CONTROL_RTS 0x02
27 #define RESEND_CTS_STATE 0x03
29 /* max number of write urbs in flight */
30 #define URB_UPPER_LIMIT 8
32 /* This driver works for the Opticon 1D barcode reader
33 * an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */
34 #define DRIVER_DESC "Opticon USB barcode to serial driver (1D)"
36 static const struct usb_device_id id_table[] = {
37 { USB_DEVICE(0x065a, 0x0009) },
40 MODULE_DEVICE_TABLE(usb, id_table);
42 /* This structure holds all of the individual device information */
43 struct opticon_private {
44 spinlock_t lock; /* protects the following flags */
51 static void opticon_process_data_packet(struct usb_serial_port *port,
52 const unsigned char *buf, size_t len)
54 tty_insert_flip_string(&port->port, buf, len);
55 tty_flip_buffer_push(&port->port);
58 static void opticon_process_status_packet(struct usb_serial_port *port,
59 const unsigned char *buf, size_t len)
61 struct opticon_private *priv = usb_get_serial_port_data(port);
64 spin_lock_irqsave(&priv->lock, flags);
69 spin_unlock_irqrestore(&priv->lock, flags);
72 static void opticon_process_read_urb(struct urb *urb)
74 struct usb_serial_port *port = urb->context;
75 const unsigned char *hdr = urb->transfer_buffer;
76 const unsigned char *data = hdr + 2;
77 size_t data_len = urb->actual_length - 2;
79 if (urb->actual_length <= 2) {
80 dev_dbg(&port->dev, "malformed packet received: %d bytes\n",
85 * Data from the device comes with a 2 byte header:
88 * This is real data to be sent to the tty layer
90 * This is a CTS level change, the third byte is the CTS
91 * value (0 for low, 1 for high).
93 if ((hdr[0] == 0x00) && (hdr[1] == 0x00)) {
94 opticon_process_data_packet(port, data, data_len);
95 } else if ((hdr[0] == 0x00) && (hdr[1] == 0x01)) {
96 opticon_process_status_packet(port, data, data_len);
98 dev_dbg(&port->dev, "unknown packet received: %02x %02x\n",
103 static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
106 struct usb_serial *serial = port->serial;
110 buffer = kzalloc(1, GFP_KERNEL);
115 /* Send the message to the vendor control endpoint
116 * of the connected device */
117 retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
119 USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
126 static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
128 struct opticon_private *priv = usb_get_serial_port_data(port);
132 spin_lock_irqsave(&priv->lock, flags);
134 spin_unlock_irqrestore(&priv->lock, flags);
137 send_control_msg(port, CONTROL_RTS, 0);
139 /* clear the halt status of the enpoint */
140 usb_clear_halt(port->serial->dev, port->read_urb->pipe);
142 res = usb_serial_generic_open(tty, port);
146 /* Request CTS line state, sometimes during opening the current
147 * CTS state can be missed. */
148 send_control_msg(port, RESEND_CTS_STATE, 1);
153 static void opticon_write_control_callback(struct urb *urb)
155 struct usb_serial_port *port = urb->context;
156 struct opticon_private *priv = usb_get_serial_port_data(port);
157 int status = urb->status;
160 /* free up the transfer buffer, as usb_free_urb() does not do this */
161 kfree(urb->transfer_buffer);
163 /* setup packet may be set if we're using it for writing */
164 kfree(urb->setup_packet);
168 "%s - non-zero urb status received: %d\n",
171 spin_lock_irqsave(&priv->lock, flags);
172 --priv->outstanding_urbs;
173 spin_unlock_irqrestore(&priv->lock, flags);
175 usb_serial_port_softint(port);
178 static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
179 const unsigned char *buf, int count)
181 struct opticon_private *priv = usb_get_serial_port_data(port);
182 struct usb_serial *serial = port->serial;
184 unsigned char *buffer;
187 struct usb_ctrlrequest *dr;
189 spin_lock_irqsave(&priv->lock, flags);
190 if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
191 spin_unlock_irqrestore(&priv->lock, flags);
192 dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
195 priv->outstanding_urbs++;
196 spin_unlock_irqrestore(&priv->lock, flags);
198 buffer = kmalloc(count, GFP_ATOMIC);
200 dev_err(&port->dev, "out of memory\n");
203 goto error_no_buffer;
206 urb = usb_alloc_urb(0, GFP_ATOMIC);
208 dev_err(&port->dev, "no more free urbs\n");
213 memcpy(buffer, buf, count);
215 usb_serial_debug_data(&port->dev, __func__, count, buffer);
217 /* The conncected devices do not have a bulk write endpoint,
218 * to transmit data to de barcode device the control endpoint is used */
219 dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO);
221 dev_err(&port->dev, "out of memory\n");
226 dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
230 dr->wLength = cpu_to_le16(count);
232 usb_fill_control_urb(urb, serial->dev,
233 usb_sndctrlpipe(serial->dev, 0),
234 (unsigned char *)dr, buffer, count,
235 opticon_write_control_callback, port);
237 /* send it down the pipe */
238 status = usb_submit_urb(urb, GFP_ATOMIC);
241 "%s - usb_submit_urb(write endpoint) failed status = %d\n",
247 /* we are done with this urb, so let the host driver
248 * really free it when it is finished with it */
259 spin_lock_irqsave(&priv->lock, flags);
260 --priv->outstanding_urbs;
261 spin_unlock_irqrestore(&priv->lock, flags);
265 static int opticon_write_room(struct tty_struct *tty)
267 struct usb_serial_port *port = tty->driver_data;
268 struct opticon_private *priv = usb_get_serial_port_data(port);
272 * We really can take almost anything the user throws at us
273 * but let's pick a nice big number to tell the tty
274 * layer that we have lots of free space, unless we don't.
276 spin_lock_irqsave(&priv->lock, flags);
277 if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
278 spin_unlock_irqrestore(&priv->lock, flags);
279 dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
282 spin_unlock_irqrestore(&priv->lock, flags);
287 static int opticon_tiocmget(struct tty_struct *tty)
289 struct usb_serial_port *port = tty->driver_data;
290 struct opticon_private *priv = usb_get_serial_port_data(port);
294 spin_lock_irqsave(&priv->lock, flags);
299 spin_unlock_irqrestore(&priv->lock, flags);
301 dev_dbg(&port->dev, "%s - %x\n", __func__, result);
305 static int opticon_tiocmset(struct tty_struct *tty,
306 unsigned int set, unsigned int clear)
308 struct usb_serial_port *port = tty->driver_data;
309 struct usb_serial *serial = port->serial;
310 struct opticon_private *priv = usb_get_serial_port_data(port);
313 bool changed = false;
316 /* We only support RTS so we only handle that */
317 spin_lock_irqsave(&priv->lock, flags);
322 if (clear & TIOCM_RTS)
324 changed = rts ^ priv->rts;
325 spin_unlock_irqrestore(&priv->lock, flags);
330 /* Send the new RTS state to the connected device */
331 mutex_lock(&serial->disc_mutex);
332 if (!serial->disconnected)
333 ret = send_control_msg(port, CONTROL_RTS, !rts);
336 mutex_unlock(&serial->disc_mutex);
341 static int get_serial_info(struct usb_serial_port *port,
342 struct serial_struct __user *serial)
344 struct serial_struct tmp;
349 memset(&tmp, 0x00, sizeof(tmp));
351 /* fake emulate a 16550 uart to make userspace code happy */
352 tmp.type = PORT_16550A;
353 tmp.line = port->serial->minor;
356 tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
357 tmp.xmit_fifo_size = 1024;
358 tmp.baud_base = 9600;
359 tmp.close_delay = 5*HZ;
360 tmp.closing_wait = 30*HZ;
362 if (copy_to_user(serial, &tmp, sizeof(*serial)))
367 static int opticon_ioctl(struct tty_struct *tty,
368 unsigned int cmd, unsigned long arg)
370 struct usb_serial_port *port = tty->driver_data;
372 dev_dbg(&port->dev, "%s - port %d, cmd = 0x%x\n", __func__, port->number, cmd);
376 return get_serial_info(port,
377 (struct serial_struct __user *)arg);
383 static int opticon_startup(struct usb_serial *serial)
385 if (!serial->num_bulk_in) {
386 dev_err(&serial->dev->dev, "no bulk in endpoint\n");
393 static int opticon_port_probe(struct usb_serial_port *port)
395 struct opticon_private *priv;
397 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
401 spin_lock_init(&priv->lock);
403 usb_set_serial_port_data(port, priv);
408 static int opticon_port_remove(struct usb_serial_port *port)
410 struct opticon_private *priv = usb_get_serial_port_data(port);
417 static struct usb_serial_driver opticon_device = {
419 .owner = THIS_MODULE,
422 .id_table = id_table,
425 .attach = opticon_startup,
426 .port_probe = opticon_port_probe,
427 .port_remove = opticon_port_remove,
428 .open = opticon_open,
429 .write = opticon_write,
430 .write_room = opticon_write_room,
431 .throttle = usb_serial_generic_throttle,
432 .unthrottle = usb_serial_generic_unthrottle,
433 .ioctl = opticon_ioctl,
434 .tiocmget = opticon_tiocmget,
435 .tiocmset = opticon_tiocmset,
436 .process_read_urb = opticon_process_read_urb,
439 static struct usb_serial_driver * const serial_drivers[] = {
440 &opticon_device, NULL
443 module_usb_serial_driver(serial_drivers, id_table);
445 MODULE_DESCRIPTION(DRIVER_DESC);
446 MODULE_LICENSE("GPL");