xref: /linux/drivers/usb/serial/omninet.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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/config.h>
39 #include <linux/kernel.h>
40 #include <linux/errno.h>
41 #include <linux/init.h>
42 #include <linux/slab.h>
43 #include <linux/tty.h>
44 #include <linux/tty_driver.h>
45 #include <linux/tty_flip.h>
46 #include <linux/module.h>
47 #include <linux/spinlock.h>
48 #include <asm/uaccess.h>
49 #include <linux/usb.h>
50 #include "usb-serial.h"
51 
52 static int debug;
53 
54 /*
55  * Version Information
56  */
57 #define DRIVER_VERSION "v1.1"
58 #define DRIVER_AUTHOR "Alessandro Zummo"
59 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
60 
61 #define ZYXEL_VENDOR_ID		0x0586
62 #define ZYXEL_OMNINET_ID	0x1000
63 #define BT_IGNITIONPRO_ID	0x2000  /* This one seems to be a re-branded ZyXEL device */
64 
65 /* function prototypes */
66 static int  omninet_open		(struct usb_serial_port *port, struct file *filp);
67 static void omninet_close		(struct usb_serial_port *port, struct file *filp);
68 static void omninet_read_bulk_callback	(struct urb *urb, struct pt_regs *regs);
69 static void omninet_write_bulk_callback	(struct urb *urb, struct pt_regs *regs);
70 static int  omninet_write		(struct usb_serial_port *port, const unsigned char *buf, int count);
71 static int  omninet_write_room		(struct usb_serial_port *port);
72 static void omninet_shutdown		(struct usb_serial *serial);
73 
74 static struct usb_device_id id_table [] = {
75 	{ USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
76 	{ USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
77 	{ }						/* Terminating entry */
78 };
79 
80 MODULE_DEVICE_TABLE (usb, id_table);
81 
82 static struct usb_driver omninet_driver = {
83 	.name =		"omninet",
84 	.probe =	usb_serial_probe,
85 	.disconnect =	usb_serial_disconnect,
86 	.id_table =	id_table,
87 	.no_dynamic_id = 	1,
88 };
89 
90 
91 static struct usb_serial_driver zyxel_omninet_device = {
92 	.driver = {
93 		.owner =	THIS_MODULE,
94 		.name =		"omninet",
95 	},
96 	.description =		"ZyXEL - omni.net lcd plus usb",
97 	.id_table =		id_table,
98 	.num_interrupt_in =	1,
99 	.num_bulk_in =		1,
100 	.num_bulk_out =		2,
101 	.num_ports =		1,
102 	.open =			omninet_open,
103 	.close =		omninet_close,
104 	.write =		omninet_write,
105 	.write_room =		omninet_write_room,
106 	.read_bulk_callback =	omninet_read_bulk_callback,
107 	.write_bulk_callback =	omninet_write_bulk_callback,
108 	.shutdown =		omninet_shutdown,
109 };
110 
111 
112 /* The protocol.
113  *
114  * The omni.net always exchange 64 bytes of data with the host. The first
115  * four bytes are the control header, you can see it in the above structure.
116  *
117  * oh_seq is a sequence number. Don't know if/how it's used.
118  * oh_len is the length of the data bytes in the packet.
119  * oh_xxx Bit-mapped, related to handshaking and status info.
120  *	I normally set it to 0x03 in trasmitted frames.
121  *	7: Active when the TA is in a CONNECTed state.
122  *	6: unknown
123  *	5: handshaking, unknown
124  *	4: handshaking, unknown
125  *	3: unknown, usually 0
126  *	2: unknown, usually 0
127  *	1: handshaking, unknown, usually set to 1 in trasmitted frames
128  *	0: handshaking, unknown, usually set to 1 in trasmitted frames
129  * oh_pad Probably a pad byte.
130  *
131  * After the header you will find data bytes if oh_len was greater than zero.
132  *
133  */
134 
135 struct omninet_header
136 {
137 	__u8	oh_seq;
138 	__u8	oh_len;
139 	__u8	oh_xxx;
140 	__u8	oh_pad;
141 };
142 
143 struct omninet_data
144 {
145 	__u8	od_outseq;	// Sequence number for bulk_out URBs
146 };
147 
148 static int omninet_open (struct usb_serial_port *port, struct file *filp)
149 {
150 	struct usb_serial	*serial = port->serial;
151 	struct usb_serial_port	*wport;
152 	struct omninet_data	*od;
153 	int			result = 0;
154 
155 	dbg("%s - port %d", __FUNCTION__, port->number);
156 
157 	od = kmalloc( sizeof(struct omninet_data), GFP_KERNEL );
158 	if( !od ) {
159 		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct omninet_data));
160 		return -ENOMEM;
161 	}
162 
163 	usb_set_serial_port_data(port, od);
164 	wport = serial->port[1];
165 	wport->tty = port->tty;
166 
167 	/* Start reading from the device */
168 	usb_fill_bulk_urb(port->read_urb, serial->dev,
169 		      usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
170 		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
171 		      omninet_read_bulk_callback, port);
172 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
173 	if (result)
174 		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
175 
176 	return result;
177 }
178 
179 static void omninet_close (struct usb_serial_port *port, struct file * filp)
180 {
181 	struct usb_serial 	*serial = port->serial;
182 	struct usb_serial_port 	*wport;
183 
184 	dbg("%s - port %d", __FUNCTION__, port->number);
185 
186 	wport = serial->port[1];
187 	usb_kill_urb(wport->write_urb);
188 	usb_kill_urb(port->read_urb);
189 
190 	kfree(usb_get_serial_port_data(port));
191 }
192 
193 
194 #define OMNINET_DATAOFFSET	0x04
195 #define OMNINET_HEADERLEN	sizeof(struct omninet_header)
196 #define OMNINET_BULKOUTSIZE 	(64 - OMNINET_HEADERLEN)
197 
198 static void omninet_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
199 {
200 	struct usb_serial_port 	*port 	= (struct usb_serial_port *)urb->context;
201 	unsigned char 		*data 	= urb->transfer_buffer;
202 	struct omninet_header 	*header = (struct omninet_header *) &data[0];
203 
204 	int i;
205 	int result;
206 
207 	dbg("%s - port %d", __FUNCTION__, port->number);
208 
209 	if (urb->status) {
210 		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
211 		return;
212 	}
213 
214 	if ((debug) && (header->oh_xxx != 0x30)) {
215 		if (urb->actual_length) {
216 			printk (KERN_DEBUG __FILE__ ": omninet_read %d: ", header->oh_len);
217 			for (i = 0; i < (header->oh_len + OMNINET_HEADERLEN); i++) {
218 				printk ("%.2x ", data[i]);
219 			}
220 			printk ("\n");
221 		}
222 	}
223 
224 	if (urb->actual_length && header->oh_len) {
225 		for (i = 0; i < header->oh_len; i++) {
226 			 tty_insert_flip_char(port->tty, data[OMNINET_DATAOFFSET + i], 0);
227 	  	}
228 	  	tty_flip_buffer_push(port->tty);
229 	}
230 
231 	/* Continue trying to always read  */
232 	usb_fill_bulk_urb(urb, port->serial->dev,
233 		      usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
234 		      urb->transfer_buffer, urb->transfer_buffer_length,
235 		      omninet_read_bulk_callback, port);
236 	result = usb_submit_urb(urb, GFP_ATOMIC);
237 	if (result)
238 		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
239 
240 	return;
241 }
242 
243 static int omninet_write (struct usb_serial_port *port, const unsigned char *buf, int count)
244 {
245 	struct usb_serial 	*serial	= port->serial;
246 	struct usb_serial_port 	*wport	= serial->port[1];
247 
248 	struct omninet_data 	*od 	= usb_get_serial_port_data(port);
249 	struct omninet_header	*header = (struct omninet_header *) wport->write_urb->transfer_buffer;
250 
251 	int			result;
252 
253 	dbg("%s - port %d", __FUNCTION__, port->number);
254 
255 	if (count == 0) {
256 		dbg("%s - write request of 0 bytes", __FUNCTION__);
257 		return (0);
258 	}
259 
260 	spin_lock(&wport->lock);
261 	if (wport->write_urb_busy) {
262 		spin_unlock(&wport->lock);
263 		dbg("%s - already writing", __FUNCTION__);
264 		return 0;
265 	}
266 	wport->write_urb_busy = 1;
267 	spin_unlock(&wport->lock);
268 
269 	count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
270 
271 	memcpy (wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET, buf, count);
272 
273 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, wport->write_urb->transfer_buffer);
274 
275 	header->oh_seq 	= od->od_outseq++;
276 	header->oh_len 	= count;
277 	header->oh_xxx  = 0x03;
278 	header->oh_pad 	= 0x00;
279 
280 	/* send the data out the bulk port, always 64 bytes */
281 	wport->write_urb->transfer_buffer_length = 64;
282 
283 	wport->write_urb->dev = serial->dev;
284 	result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
285 	if (result) {
286 		wport->write_urb_busy = 0;
287 		err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
288 	} else
289 		result = count;
290 
291 	return result;
292 }
293 
294 
295 static int omninet_write_room (struct usb_serial_port *port)
296 {
297 	struct usb_serial 	*serial = port->serial;
298 	struct usb_serial_port 	*wport 	= serial->port[1];
299 
300 	int room = 0; // Default: no room
301 
302 	if (wport->write_urb_busy)
303 		room = wport->bulk_out_size - OMNINET_HEADERLEN;
304 
305 	dbg("%s - returns %d", __FUNCTION__, room);
306 
307 	return (room);
308 }
309 
310 static void omninet_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
311 {
312 /*	struct omninet_header	*header = (struct omninet_header  *) urb->transfer_buffer; */
313 	struct usb_serial_port 	*port   = (struct usb_serial_port *) urb->context;
314 
315 	dbg("%s - port %0x\n", __FUNCTION__, port->number);
316 
317 	port->write_urb_busy = 0;
318 	if (urb->status) {
319 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
320 		return;
321 	}
322 
323 	usb_serial_port_softint(port);
324 }
325 
326 
327 static void omninet_shutdown (struct usb_serial *serial)
328 {
329 	dbg ("%s", __FUNCTION__);
330 }
331 
332 
333 static int __init omninet_init (void)
334 {
335 	int retval;
336 	retval = usb_serial_register(&zyxel_omninet_device);
337 	if (retval)
338 		goto failed_usb_serial_register;
339 	retval = usb_register(&omninet_driver);
340 	if (retval)
341 		goto failed_usb_register;
342 	info(DRIVER_VERSION ":" DRIVER_DESC);
343 	return 0;
344 failed_usb_register:
345 	usb_serial_deregister(&zyxel_omninet_device);
346 failed_usb_serial_register:
347 	return retval;
348 }
349 
350 
351 static void __exit omninet_exit (void)
352 {
353 	usb_deregister (&omninet_driver);
354 	usb_serial_deregister (&zyxel_omninet_device);
355 }
356 
357 
358 module_init(omninet_init);
359 module_exit(omninet_exit);
360 
361 MODULE_AUTHOR( DRIVER_AUTHOR );
362 MODULE_DESCRIPTION( DRIVER_DESC );
363 MODULE_LICENSE("GPL");
364 
365 module_param(debug, bool, S_IRUGO | S_IWUSR);
366 MODULE_PARM_DESC(debug, "Debug enabled or not");
367