xref: /linux/drivers/usb/serial/omninet.c (revision 6e8331ac6973435b1e7604c30f2ad394035b46e1)
1 /*
2  * USB ZyXEL omni.net LCD PLUS driver
3  *
4  *	This program is free software; you can redistribute it and/or modify
5  *	it under the terms of the GNU General Public License as published by
6  *	the Free Software Foundation; either version 2 of the License, or
7  *	(at your option) any later version.
8  *
9  * See Documentation/usb/usb-serial.txt for more information on using this driver
10  *
11  * Please report both successes and troubles to the author at omninet@kroah.com
12  *
13  * (05/30/2001) gkh
14  *	switched from using spinlock to a semaphore, which fixes lots of problems.
15  *
16  * (04/08/2001) gb
17  *	Identify version on module load.
18  *
19  * (11/01/2000) Adam J. Richter
20  *	usb_device_id table support
21  *
22  * (10/05/2000) gkh
23  *	Fixed bug with urb->dev not being set properly, now that the usb
24  *	core needs it.
25  *
26  * (08/28/2000) gkh
27  *	Added locks for SMP safeness.
28  *	Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
29  *	than once.
30  *	Fixed potential race in omninet_write_bulk_callback
31  *
32  * (07/19/2000) gkh
33  *	Added module_init and module_exit functions to handle the fact that this
34  *	driver is a loadable module now.
35  *
36  */
37 
38 #include <linux/kernel.h>
39 #include <linux/errno.h>
40 #include <linux/init.h>
41 #include <linux/slab.h>
42 #include <linux/tty.h>
43 #include <linux/tty_driver.h>
44 #include <linux/tty_flip.h>
45 #include <linux/module.h>
46 #include <linux/spinlock.h>
47 #include <asm/uaccess.h>
48 #include <linux/usb.h>
49 #include <linux/usb/serial.h>
50 
51 static int debug;
52 
53 /*
54  * Version Information
55  */
56 #define DRIVER_VERSION "v1.1"
57 #define DRIVER_AUTHOR "Alessandro Zummo"
58 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
59 
60 #define ZYXEL_VENDOR_ID		0x0586
61 #define ZYXEL_OMNINET_ID	0x1000
62 #define BT_IGNITIONPRO_ID	0x2000  /* This one seems to be a re-branded ZyXEL device */
63 
64 /* function prototypes */
65 static int  omninet_open		(struct usb_serial_port *port, struct file *filp);
66 static void omninet_close		(struct usb_serial_port *port, struct file *filp);
67 static void omninet_read_bulk_callback	(struct urb *urb, struct pt_regs *regs);
68 static void omninet_write_bulk_callback	(struct urb *urb, struct pt_regs *regs);
69 static int  omninet_write		(struct usb_serial_port *port, const unsigned char *buf, int count);
70 static int  omninet_write_room		(struct usb_serial_port *port);
71 static void omninet_shutdown		(struct usb_serial *serial);
72 
73 static struct usb_device_id id_table [] = {
74 	{ USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
75 	{ USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
76 	{ }						/* Terminating entry */
77 };
78 
79 MODULE_DEVICE_TABLE (usb, id_table);
80 
81 static struct usb_driver omninet_driver = {
82 	.name =		"omninet",
83 	.probe =	usb_serial_probe,
84 	.disconnect =	usb_serial_disconnect,
85 	.id_table =	id_table,
86 	.no_dynamic_id = 	1,
87 };
88 
89 
90 static struct usb_serial_driver zyxel_omninet_device = {
91 	.driver = {
92 		.owner =	THIS_MODULE,
93 		.name =		"omninet",
94 	},
95 	.description =		"ZyXEL - omni.net lcd plus usb",
96 	.id_table =		id_table,
97 	.num_interrupt_in =	1,
98 	.num_bulk_in =		1,
99 	.num_bulk_out =		2,
100 	.num_ports =		1,
101 	.open =			omninet_open,
102 	.close =		omninet_close,
103 	.write =		omninet_write,
104 	.write_room =		omninet_write_room,
105 	.read_bulk_callback =	omninet_read_bulk_callback,
106 	.write_bulk_callback =	omninet_write_bulk_callback,
107 	.shutdown =		omninet_shutdown,
108 };
109 
110 
111 /* The protocol.
112  *
113  * The omni.net always exchange 64 bytes of data with the host. The first
114  * four bytes are the control header, you can see it in the above structure.
115  *
116  * oh_seq is a sequence number. Don't know if/how it's used.
117  * oh_len is the length of the data bytes in the packet.
118  * oh_xxx Bit-mapped, related to handshaking and status info.
119  *	I normally set it to 0x03 in trasmitted frames.
120  *	7: Active when the TA is in a CONNECTed state.
121  *	6: unknown
122  *	5: handshaking, unknown
123  *	4: handshaking, unknown
124  *	3: unknown, usually 0
125  *	2: unknown, usually 0
126  *	1: handshaking, unknown, usually set to 1 in trasmitted frames
127  *	0: handshaking, unknown, usually set to 1 in trasmitted frames
128  * oh_pad Probably a pad byte.
129  *
130  * After the header you will find data bytes if oh_len was greater than zero.
131  *
132  */
133 
134 struct omninet_header
135 {
136 	__u8	oh_seq;
137 	__u8	oh_len;
138 	__u8	oh_xxx;
139 	__u8	oh_pad;
140 };
141 
142 struct omninet_data
143 {
144 	__u8	od_outseq;	// Sequence number for bulk_out URBs
145 };
146 
147 static int omninet_open (struct usb_serial_port *port, struct file *filp)
148 {
149 	struct usb_serial	*serial = port->serial;
150 	struct usb_serial_port	*wport;
151 	struct omninet_data	*od;
152 	int			result = 0;
153 
154 	dbg("%s - port %d", __FUNCTION__, port->number);
155 
156 	od = kmalloc( sizeof(struct omninet_data), GFP_KERNEL );
157 	if( !od ) {
158 		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct omninet_data));
159 		return -ENOMEM;
160 	}
161 
162 	usb_set_serial_port_data(port, od);
163 	wport = serial->port[1];
164 	wport->tty = port->tty;
165 
166 	/* Start reading from the device */
167 	usb_fill_bulk_urb(port->read_urb, serial->dev,
168 		      usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
169 		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
170 		      omninet_read_bulk_callback, port);
171 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
172 	if (result)
173 		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
174 
175 	return result;
176 }
177 
178 static void omninet_close (struct usb_serial_port *port, struct file * filp)
179 {
180 	struct usb_serial 	*serial = port->serial;
181 	struct usb_serial_port 	*wport;
182 
183 	dbg("%s - port %d", __FUNCTION__, port->number);
184 
185 	wport = serial->port[1];
186 	usb_kill_urb(wport->write_urb);
187 	usb_kill_urb(port->read_urb);
188 
189 	kfree(usb_get_serial_port_data(port));
190 }
191 
192 
193 #define OMNINET_DATAOFFSET	0x04
194 #define OMNINET_HEADERLEN	sizeof(struct omninet_header)
195 #define OMNINET_BULKOUTSIZE 	(64 - OMNINET_HEADERLEN)
196 
197 static void omninet_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
198 {
199 	struct usb_serial_port 	*port 	= (struct usb_serial_port *)urb->context;
200 	unsigned char 		*data 	= urb->transfer_buffer;
201 	struct omninet_header 	*header = (struct omninet_header *) &data[0];
202 
203 	int i;
204 	int result;
205 
206 	dbg("%s - port %d", __FUNCTION__, port->number);
207 
208 	if (urb->status) {
209 		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
210 		return;
211 	}
212 
213 	if ((debug) && (header->oh_xxx != 0x30)) {
214 		if (urb->actual_length) {
215 			printk (KERN_DEBUG __FILE__ ": omninet_read %d: ", header->oh_len);
216 			for (i = 0; i < (header->oh_len + OMNINET_HEADERLEN); i++) {
217 				printk ("%.2x ", data[i]);
218 			}
219 			printk ("\n");
220 		}
221 	}
222 
223 	if (urb->actual_length && header->oh_len) {
224 		for (i = 0; i < header->oh_len; i++) {
225 			 tty_insert_flip_char(port->tty, data[OMNINET_DATAOFFSET + i], 0);
226 	  	}
227 	  	tty_flip_buffer_push(port->tty);
228 	}
229 
230 	/* Continue trying to always read  */
231 	usb_fill_bulk_urb(urb, port->serial->dev,
232 		      usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
233 		      urb->transfer_buffer, urb->transfer_buffer_length,
234 		      omninet_read_bulk_callback, port);
235 	result = usb_submit_urb(urb, GFP_ATOMIC);
236 	if (result)
237 		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
238 
239 	return;
240 }
241 
242 static int omninet_write (struct usb_serial_port *port, const unsigned char *buf, int count)
243 {
244 	struct usb_serial 	*serial	= port->serial;
245 	struct usb_serial_port 	*wport	= serial->port[1];
246 
247 	struct omninet_data 	*od 	= usb_get_serial_port_data(port);
248 	struct omninet_header	*header = (struct omninet_header *) wport->write_urb->transfer_buffer;
249 
250 	int			result;
251 
252 	dbg("%s - port %d", __FUNCTION__, port->number);
253 
254 	if (count == 0) {
255 		dbg("%s - write request of 0 bytes", __FUNCTION__);
256 		return (0);
257 	}
258 
259 	spin_lock(&wport->lock);
260 	if (wport->write_urb_busy) {
261 		spin_unlock(&wport->lock);
262 		dbg("%s - already writing", __FUNCTION__);
263 		return 0;
264 	}
265 	wport->write_urb_busy = 1;
266 	spin_unlock(&wport->lock);
267 
268 	count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
269 
270 	memcpy (wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET, buf, count);
271 
272 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, wport->write_urb->transfer_buffer);
273 
274 	header->oh_seq 	= od->od_outseq++;
275 	header->oh_len 	= count;
276 	header->oh_xxx  = 0x03;
277 	header->oh_pad 	= 0x00;
278 
279 	/* send the data out the bulk port, always 64 bytes */
280 	wport->write_urb->transfer_buffer_length = 64;
281 
282 	wport->write_urb->dev = serial->dev;
283 	result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
284 	if (result) {
285 		wport->write_urb_busy = 0;
286 		err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
287 	} else
288 		result = count;
289 
290 	return result;
291 }
292 
293 
294 static int omninet_write_room (struct usb_serial_port *port)
295 {
296 	struct usb_serial 	*serial = port->serial;
297 	struct usb_serial_port 	*wport 	= serial->port[1];
298 
299 	int room = 0; // Default: no room
300 
301 	if (wport->write_urb_busy)
302 		room = wport->bulk_out_size - OMNINET_HEADERLEN;
303 
304 	dbg("%s - returns %d", __FUNCTION__, room);
305 
306 	return (room);
307 }
308 
309 static void omninet_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
310 {
311 /*	struct omninet_header	*header = (struct omninet_header  *) urb->transfer_buffer; */
312 	struct usb_serial_port 	*port   = (struct usb_serial_port *) urb->context;
313 
314 	dbg("%s - port %0x\n", __FUNCTION__, port->number);
315 
316 	port->write_urb_busy = 0;
317 	if (urb->status) {
318 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
319 		return;
320 	}
321 
322 	usb_serial_port_softint(port);
323 }
324 
325 
326 static void omninet_shutdown (struct usb_serial *serial)
327 {
328 	dbg ("%s", __FUNCTION__);
329 }
330 
331 
332 static int __init omninet_init (void)
333 {
334 	int retval;
335 	retval = usb_serial_register(&zyxel_omninet_device);
336 	if (retval)
337 		goto failed_usb_serial_register;
338 	retval = usb_register(&omninet_driver);
339 	if (retval)
340 		goto failed_usb_register;
341 	info(DRIVER_VERSION ":" DRIVER_DESC);
342 	return 0;
343 failed_usb_register:
344 	usb_serial_deregister(&zyxel_omninet_device);
345 failed_usb_serial_register:
346 	return retval;
347 }
348 
349 
350 static void __exit omninet_exit (void)
351 {
352 	usb_deregister (&omninet_driver);
353 	usb_serial_deregister (&zyxel_omninet_device);
354 }
355 
356 
357 module_init(omninet_init);
358 module_exit(omninet_exit);
359 
360 MODULE_AUTHOR( DRIVER_AUTHOR );
361 MODULE_DESCRIPTION( DRIVER_DESC );
362 MODULE_LICENSE("GPL");
363 
364 module_param(debug, bool, S_IRUGO | S_IWUSR);
365 MODULE_PARM_DESC(debug, "Debug enabled or not");
366