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,
129 static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
131 struct opticon_private *priv = usb_get_serial_port_data(port);
135 spin_lock_irqsave(&priv->lock, flags);
137 spin_unlock_irqrestore(&priv->lock, flags);
140 send_control_msg(port, CONTROL_RTS, 0);
142 /* clear the halt status of the endpoint */
143 usb_clear_halt(port->serial->dev, port->read_urb->pipe);
145 res = usb_serial_generic_open(tty, port);
149 /* Request CTS line state, sometimes during opening the current
150 * CTS state can be missed. */
151 send_control_msg(port, RESEND_CTS_STATE, 1);
156 static void opticon_write_control_callback(struct urb *urb)
158 struct usb_serial_port *port = urb->context;
159 struct opticon_private *priv = usb_get_serial_port_data(port);
160 int status = urb->status;
163 /* free up the transfer buffer, as usb_free_urb() does not do this */
164 kfree(urb->transfer_buffer);
166 /* setup packet may be set if we're using it for writing */
167 kfree(urb->setup_packet);
171 "%s - non-zero urb status received: %d\n",
174 spin_lock_irqsave(&priv->lock, flags);
175 --priv->outstanding_urbs;
176 spin_unlock_irqrestore(&priv->lock, flags);
178 usb_serial_port_softint(port);
181 static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
182 const unsigned char *buf, int count)
184 struct opticon_private *priv = usb_get_serial_port_data(port);
185 struct usb_serial *serial = port->serial;
187 unsigned char *buffer;
190 struct usb_ctrlrequest *dr;
192 spin_lock_irqsave(&priv->lock, flags);
193 if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
194 spin_unlock_irqrestore(&priv->lock, flags);
195 dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
198 priv->outstanding_urbs++;
199 spin_unlock_irqrestore(&priv->lock, flags);
201 buffer = kmalloc(count, GFP_ATOMIC);
204 goto error_no_buffer;
207 urb = usb_alloc_urb(0, GFP_ATOMIC);
213 memcpy(buffer, buf, count);
215 usb_serial_debug_data(&port->dev, __func__, count, buffer);
217 /* The connected 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);
225 dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
229 dr->wLength = cpu_to_le16(count);
231 usb_fill_control_urb(urb, serial->dev,
232 usb_sndctrlpipe(serial->dev, 0),
233 (unsigned char *)dr, buffer, count,
234 opticon_write_control_callback, port);
236 /* send it down the pipe */
237 status = usb_submit_urb(urb, GFP_ATOMIC);
240 "%s - usb_submit_urb(write endpoint) failed status = %d\n",
246 /* we are done with this urb, so let the host driver
247 * really free it when it is finished with it */
258 spin_lock_irqsave(&priv->lock, flags);
259 --priv->outstanding_urbs;
260 spin_unlock_irqrestore(&priv->lock, flags);
264 static int opticon_write_room(struct tty_struct *tty)
266 struct usb_serial_port *port = tty->driver_data;
267 struct opticon_private *priv = usb_get_serial_port_data(port);
271 * We really can take almost anything the user throws at us
272 * but let's pick a nice big number to tell the tty
273 * layer that we have lots of free space, unless we don't.
275 spin_lock_irqsave(&priv->lock, flags);
276 if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
277 spin_unlock_irqrestore(&priv->lock, flags);
278 dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
281 spin_unlock_irqrestore(&priv->lock, flags);
286 static int opticon_tiocmget(struct tty_struct *tty)
288 struct usb_serial_port *port = tty->driver_data;
289 struct opticon_private *priv = usb_get_serial_port_data(port);
293 spin_lock_irqsave(&priv->lock, flags);
298 spin_unlock_irqrestore(&priv->lock, flags);
300 dev_dbg(&port->dev, "%s - %x\n", __func__, result);
304 static int opticon_tiocmset(struct tty_struct *tty,
305 unsigned int set, unsigned int clear)
307 struct usb_serial_port *port = tty->driver_data;
308 struct opticon_private *priv = usb_get_serial_port_data(port);
311 bool changed = false;
314 /* We only support RTS so we only handle that */
315 spin_lock_irqsave(&priv->lock, flags);
320 if (clear & TIOCM_RTS)
322 changed = rts ^ priv->rts;
323 spin_unlock_irqrestore(&priv->lock, flags);
328 ret = send_control_msg(port, CONTROL_RTS, !rts);
330 return usb_translate_errors(ret);
335 static int get_serial_info(struct usb_serial_port *port,
336 struct serial_struct __user *serial)
338 struct serial_struct tmp;
343 memset(&tmp, 0x00, sizeof(tmp));
345 /* fake emulate a 16550 uart to make userspace code happy */
346 tmp.type = PORT_16550A;
347 tmp.line = port->minor;
350 tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
351 tmp.xmit_fifo_size = 1024;
352 tmp.baud_base = 9600;
353 tmp.close_delay = 5*HZ;
354 tmp.closing_wait = 30*HZ;
356 if (copy_to_user(serial, &tmp, sizeof(*serial)))
361 static int opticon_ioctl(struct tty_struct *tty,
362 unsigned int cmd, unsigned long arg)
364 struct usb_serial_port *port = tty->driver_data;
368 return get_serial_info(port,
369 (struct serial_struct __user *)arg);
375 static int opticon_startup(struct usb_serial *serial)
377 if (!serial->num_bulk_in) {
378 dev_err(&serial->dev->dev, "no bulk in endpoint\n");
385 static int opticon_port_probe(struct usb_serial_port *port)
387 struct opticon_private *priv;
389 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
393 spin_lock_init(&priv->lock);
395 usb_set_serial_port_data(port, priv);
400 static int opticon_port_remove(struct usb_serial_port *port)
402 struct opticon_private *priv = usb_get_serial_port_data(port);
409 static struct usb_serial_driver opticon_device = {
411 .owner = THIS_MODULE,
414 .id_table = id_table,
417 .attach = opticon_startup,
418 .port_probe = opticon_port_probe,
419 .port_remove = opticon_port_remove,
420 .open = opticon_open,
421 .write = opticon_write,
422 .write_room = opticon_write_room,
423 .throttle = usb_serial_generic_throttle,
424 .unthrottle = usb_serial_generic_unthrottle,
425 .ioctl = opticon_ioctl,
426 .tiocmget = opticon_tiocmget,
427 .tiocmset = opticon_tiocmset,
428 .process_read_urb = opticon_process_read_urb,
431 static struct usb_serial_driver * const serial_drivers[] = {
432 &opticon_device, NULL
435 module_usb_serial_driver(serial_drivers, id_table);
437 MODULE_DESCRIPTION(DRIVER_DESC);
438 MODULE_LICENSE("GPL");