xref: /openbmc/linux/drivers/usb/serial/omninet.c (revision 64c70b1c)
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);
68 static void omninet_write_bulk_callback	(struct urb *urb);
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 static int omninet_attach		(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 	.usb_driver =		&omninet_driver,
98 	.id_table =		id_table,
99 	.num_interrupt_in =	1,
100 	.num_bulk_in =		1,
101 	.num_bulk_out =		2,
102 	.num_ports =		1,
103 	.attach =		omninet_attach,
104 	.open =			omninet_open,
105 	.close =		omninet_close,
106 	.write =		omninet_write,
107 	.write_room =		omninet_write_room,
108 	.read_bulk_callback =	omninet_read_bulk_callback,
109 	.write_bulk_callback =	omninet_write_bulk_callback,
110 	.shutdown =		omninet_shutdown,
111 };
112 
113 
114 /* The protocol.
115  *
116  * The omni.net always exchange 64 bytes of data with the host. The first
117  * four bytes are the control header, you can see it in the above structure.
118  *
119  * oh_seq is a sequence number. Don't know if/how it's used.
120  * oh_len is the length of the data bytes in the packet.
121  * oh_xxx Bit-mapped, related to handshaking and status info.
122  *	I normally set it to 0x03 in trasmitted frames.
123  *	7: Active when the TA is in a CONNECTed state.
124  *	6: unknown
125  *	5: handshaking, unknown
126  *	4: handshaking, unknown
127  *	3: unknown, usually 0
128  *	2: unknown, usually 0
129  *	1: handshaking, unknown, usually set to 1 in trasmitted frames
130  *	0: handshaking, unknown, usually set to 1 in trasmitted frames
131  * oh_pad Probably a pad byte.
132  *
133  * After the header you will find data bytes if oh_len was greater than zero.
134  *
135  */
136 
137 struct omninet_header
138 {
139 	__u8	oh_seq;
140 	__u8	oh_len;
141 	__u8	oh_xxx;
142 	__u8	oh_pad;
143 };
144 
145 struct omninet_data
146 {
147 	__u8	od_outseq;	// Sequence number for bulk_out URBs
148 };
149 
150 static int omninet_attach (struct usb_serial *serial)
151 {
152 	struct omninet_data *od;
153 	struct usb_serial_port *port = serial->port[0];
154 
155 	od = kmalloc( sizeof(struct omninet_data), GFP_KERNEL );
156 	if( !od ) {
157 		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct omninet_data));
158 		return -ENOMEM;
159 	}
160 	usb_set_serial_port_data(port, od);
161 	return 0;
162 }
163 
164 static int omninet_open (struct usb_serial_port *port, struct file *filp)
165 {
166 	struct usb_serial	*serial = port->serial;
167 	struct usb_serial_port	*wport;
168 	int			result = 0;
169 
170 	dbg("%s - port %d", __FUNCTION__, port->number);
171 
172 	wport = serial->port[1];
173 	wport->tty = port->tty;
174 
175 	/* Start reading from the device */
176 	usb_fill_bulk_urb(port->read_urb, serial->dev,
177 		      usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
178 		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
179 		      omninet_read_bulk_callback, port);
180 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
181 	if (result) {
182 		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
183 	}
184 
185 	return result;
186 }
187 
188 static void omninet_close (struct usb_serial_port *port, struct file * filp)
189 {
190 	dbg("%s - port %d", __FUNCTION__, port->number);
191 	usb_kill_urb(port->read_urb);
192 }
193 
194 
195 #define OMNINET_DATAOFFSET	0x04
196 #define OMNINET_HEADERLEN	sizeof(struct omninet_header)
197 #define OMNINET_BULKOUTSIZE 	(64 - OMNINET_HEADERLEN)
198 
199 static void omninet_read_bulk_callback (struct urb *urb)
200 {
201 	struct usb_serial_port 	*port 	= (struct usb_serial_port *)urb->context;
202 	unsigned char 		*data 	= urb->transfer_buffer;
203 	struct omninet_header 	*header = (struct omninet_header *) &data[0];
204 
205 	int i;
206 	int result;
207 
208 	dbg("%s - port %d", __FUNCTION__, port->number);
209 
210 	if (urb->status) {
211 		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
212 		return;
213 	}
214 
215 	if ((debug) && (header->oh_xxx != 0x30)) {
216 		if (urb->actual_length) {
217 			printk (KERN_DEBUG __FILE__ ": omninet_read %d: ", header->oh_len);
218 			for (i = 0; i < (header->oh_len + OMNINET_HEADERLEN); i++) {
219 				printk ("%.2x ", data[i]);
220 			}
221 			printk ("\n");
222 		}
223 	}
224 
225 	if (urb->actual_length && header->oh_len) {
226 		for (i = 0; i < header->oh_len; i++) {
227 			 tty_insert_flip_char(port->tty, data[OMNINET_DATAOFFSET + i], 0);
228 	  	}
229 	  	tty_flip_buffer_push(port->tty);
230 	}
231 
232 	/* Continue trying to always read  */
233 	usb_fill_bulk_urb(urb, port->serial->dev,
234 		      usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
235 		      urb->transfer_buffer, urb->transfer_buffer_length,
236 		      omninet_read_bulk_callback, port);
237 	result = usb_submit_urb(urb, GFP_ATOMIC);
238 	if (result)
239 		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
240 
241 	return;
242 }
243 
244 static int omninet_write (struct usb_serial_port *port, const unsigned char *buf, int count)
245 {
246 	struct usb_serial 	*serial	= port->serial;
247 	struct usb_serial_port 	*wport	= serial->port[1];
248 
249 	struct omninet_data 	*od 	= usb_get_serial_port_data(port);
250 	struct omninet_header	*header = (struct omninet_header *) wport->write_urb->transfer_buffer;
251 
252 	int			result;
253 
254 	dbg("%s - port %d", __FUNCTION__, port->number);
255 
256 	if (count == 0) {
257 		dbg("%s - write request of 0 bytes", __FUNCTION__);
258 		return (0);
259 	}
260 
261 	spin_lock_bh(&wport->lock);
262 	if (wport->write_urb_busy) {
263 		spin_unlock_bh(&wport->lock);
264 		dbg("%s - already writing", __FUNCTION__);
265 		return 0;
266 	}
267 	wport->write_urb_busy = 1;
268 	spin_unlock_bh(&wport->lock);
269 
270 	count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
271 
272 	memcpy (wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET, buf, count);
273 
274 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, wport->write_urb->transfer_buffer);
275 
276 	header->oh_seq 	= od->od_outseq++;
277 	header->oh_len 	= count;
278 	header->oh_xxx  = 0x03;
279 	header->oh_pad 	= 0x00;
280 
281 	/* send the data out the bulk port, always 64 bytes */
282 	wport->write_urb->transfer_buffer_length = 64;
283 
284 	wport->write_urb->dev = serial->dev;
285 	result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
286 	if (result) {
287 		wport->write_urb_busy = 0;
288 		err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
289 	} else
290 		result = count;
291 
292 	return result;
293 }
294 
295 
296 static int omninet_write_room (struct usb_serial_port *port)
297 {
298 	struct usb_serial 	*serial = port->serial;
299 	struct usb_serial_port 	*wport 	= serial->port[1];
300 
301 	int room = 0; // Default: no room
302 
303 	if (wport->write_urb_busy)
304 		room = wport->bulk_out_size - OMNINET_HEADERLEN;
305 
306 	dbg("%s - returns %d", __FUNCTION__, room);
307 
308 	return (room);
309 }
310 
311 static void omninet_write_bulk_callback (struct urb *urb)
312 {
313 /*	struct omninet_header	*header = (struct omninet_header  *) urb->transfer_buffer; */
314 	struct usb_serial_port 	*port   = (struct usb_serial_port *) urb->context;
315 
316 	dbg("%s - port %0x\n", __FUNCTION__, port->number);
317 
318 	port->write_urb_busy = 0;
319 	if (urb->status) {
320 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
321 		return;
322 	}
323 
324 	usb_serial_port_softint(port);
325 }
326 
327 
328 static void omninet_shutdown (struct usb_serial *serial)
329 {
330 	struct usb_serial_port *wport = serial->port[1];
331 	struct usb_serial_port *port = serial->port[0];
332 	dbg ("%s", __FUNCTION__);
333 
334 	usb_kill_urb(wport->write_urb);
335 	kfree(usb_get_serial_port_data(port));
336 }
337 
338 
339 static int __init omninet_init (void)
340 {
341 	int retval;
342 	retval = usb_serial_register(&zyxel_omninet_device);
343 	if (retval)
344 		goto failed_usb_serial_register;
345 	retval = usb_register(&omninet_driver);
346 	if (retval)
347 		goto failed_usb_register;
348 	info(DRIVER_VERSION ":" DRIVER_DESC);
349 	return 0;
350 failed_usb_register:
351 	usb_serial_deregister(&zyxel_omninet_device);
352 failed_usb_serial_register:
353 	return retval;
354 }
355 
356 
357 static void __exit omninet_exit (void)
358 {
359 	usb_deregister (&omninet_driver);
360 	usb_serial_deregister (&zyxel_omninet_device);
361 }
362 
363 
364 module_init(omninet_init);
365 module_exit(omninet_exit);
366 
367 MODULE_AUTHOR( DRIVER_AUTHOR );
368 MODULE_DESCRIPTION( DRIVER_DESC );
369 MODULE_LICENSE("GPL");
370 
371 module_param(debug, bool, S_IRUGO | S_IWUSR);
372 MODULE_PARM_DESC(debug, "Debug enabled or not");
373