xref: /openbmc/linux/drivers/usb/serial/omninet.c (revision 5833041f1b130e5823a99d03b14538282e5ad345)
1 /*
2  * USB ZyXEL omni.net LCD PLUS driver
3  *
4  *	This program is free software; you can redistribute it and/or
5  *	modify it under the terms of the GNU General Public License version
6  *	2 as published by the Free Software Foundation.
7  *
8  * See Documentation/usb/usb-serial.txt for more information on using this
9  * driver
10  *
11  * Please report both successes and troubles to the author at omninet@kroah.com
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/tty.h>
19 #include <linux/tty_driver.h>
20 #include <linux/tty_flip.h>
21 #include <linux/module.h>
22 #include <linux/uaccess.h>
23 #include <linux/usb.h>
24 #include <linux/usb/serial.h>
25 
26 static int debug;
27 
28 /*
29  * Version Information
30  */
31 #define DRIVER_VERSION "v1.1"
32 #define DRIVER_AUTHOR "Alessandro Zummo"
33 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
34 
35 #define ZYXEL_VENDOR_ID		0x0586
36 #define ZYXEL_OMNINET_ID	0x1000
37 /* This one seems to be a re-branded ZyXEL device */
38 #define BT_IGNITIONPRO_ID	0x2000
39 
40 /* function prototypes */
41 static int  omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
42 static void omninet_close(struct usb_serial_port *port);
43 static void omninet_read_bulk_callback(struct urb *urb);
44 static void omninet_write_bulk_callback(struct urb *urb);
45 static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
46 				const unsigned char *buf, int count);
47 static int  omninet_write_room(struct tty_struct *tty);
48 static void omninet_disconnect(struct usb_serial *serial);
49 static void omninet_release(struct usb_serial *serial);
50 static int omninet_attach(struct usb_serial *serial);
51 
52 static const struct usb_device_id id_table[] = {
53 	{ USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
54 	{ USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
55 	{ }						/* Terminating entry */
56 };
57 
58 MODULE_DEVICE_TABLE(usb, id_table);
59 
60 static struct usb_driver omninet_driver = {
61 	.name =		"omninet",
62 	.probe =	usb_serial_probe,
63 	.disconnect =	usb_serial_disconnect,
64 	.id_table =	id_table,
65 	.no_dynamic_id = 	1,
66 };
67 
68 
69 static struct usb_serial_driver zyxel_omninet_device = {
70 	.driver = {
71 		.owner =	THIS_MODULE,
72 		.name =		"omninet",
73 	},
74 	.description =		"ZyXEL - omni.net lcd plus usb",
75 	.usb_driver =		&omninet_driver,
76 	.id_table =		id_table,
77 	.num_ports =		1,
78 	.attach =		omninet_attach,
79 	.open =			omninet_open,
80 	.close =		omninet_close,
81 	.write =		omninet_write,
82 	.write_room =		omninet_write_room,
83 	.read_bulk_callback =	omninet_read_bulk_callback,
84 	.write_bulk_callback =	omninet_write_bulk_callback,
85 	.disconnect =		omninet_disconnect,
86 	.release =		omninet_release,
87 };
88 
89 
90 /* The protocol.
91  *
92  * The omni.net always exchange 64 bytes of data with the host. The first
93  * four bytes are the control header, you can see it in the above structure.
94  *
95  * oh_seq is a sequence number. Don't know if/how it's used.
96  * oh_len is the length of the data bytes in the packet.
97  * oh_xxx Bit-mapped, related to handshaking and status info.
98  *	I normally set it to 0x03 in trasmitted frames.
99  *	7: Active when the TA is in a CONNECTed state.
100  *	6: unknown
101  *	5: handshaking, unknown
102  *	4: handshaking, unknown
103  *	3: unknown, usually 0
104  *	2: unknown, usually 0
105  *	1: handshaking, unknown, usually set to 1 in trasmitted frames
106  *	0: handshaking, unknown, usually set to 1 in trasmitted frames
107  * oh_pad Probably a pad byte.
108  *
109  * After the header you will find data bytes if oh_len was greater than zero.
110  *
111  */
112 
113 struct omninet_header {
114 	__u8	oh_seq;
115 	__u8	oh_len;
116 	__u8	oh_xxx;
117 	__u8	oh_pad;
118 };
119 
120 struct omninet_data {
121 	__u8	od_outseq;	/* Sequence number for bulk_out URBs */
122 };
123 
124 static int omninet_attach(struct usb_serial *serial)
125 {
126 	struct omninet_data *od;
127 	struct usb_serial_port *port = serial->port[0];
128 
129 	od = kmalloc(sizeof(struct omninet_data), GFP_KERNEL);
130 	if (!od) {
131 		dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n",
132 			__func__, sizeof(struct omninet_data));
133 		return -ENOMEM;
134 	}
135 	usb_set_serial_port_data(port, od);
136 	return 0;
137 }
138 
139 static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port)
140 {
141 	struct usb_serial	*serial = port->serial;
142 	struct usb_serial_port	*wport;
143 	int			result = 0;
144 
145 	dbg("%s - port %d", __func__, port->number);
146 
147 	wport = serial->port[1];
148 	tty_port_tty_set(&wport->port, tty);
149 
150 	/* Start reading from the device */
151 	usb_fill_bulk_urb(port->read_urb, serial->dev,
152 			usb_rcvbulkpipe(serial->dev,
153 				port->bulk_in_endpointAddress),
154 			port->read_urb->transfer_buffer,
155 			port->read_urb->transfer_buffer_length,
156 			omninet_read_bulk_callback, port);
157 
158 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
159 	if (result)
160 		dev_err(&port->dev,
161 			"%s - failed submitting read urb, error %d\n",
162 			__func__, result);
163 	return result;
164 }
165 
166 static void omninet_close(struct usb_serial_port *port)
167 {
168 	dbg("%s - port %d", __func__, port->number);
169 	usb_kill_urb(port->read_urb);
170 }
171 
172 
173 #define OMNINET_DATAOFFSET	0x04
174 #define OMNINET_HEADERLEN	sizeof(struct omninet_header)
175 #define OMNINET_BULKOUTSIZE 	(64 - OMNINET_HEADERLEN)
176 
177 static void omninet_read_bulk_callback(struct urb *urb)
178 {
179 	struct usb_serial_port 	*port 	= urb->context;
180 	unsigned char 		*data 	= urb->transfer_buffer;
181 	struct omninet_header 	*header = (struct omninet_header *) &data[0];
182 	int status = urb->status;
183 	int result;
184 	int i;
185 
186 	dbg("%s - port %d", __func__, port->number);
187 
188 	if (status) {
189 		dbg("%s - nonzero read bulk status received: %d",
190 		    __func__, status);
191 		return;
192 	}
193 
194 	if (debug && header->oh_xxx != 0x30) {
195 		if (urb->actual_length) {
196 			printk(KERN_DEBUG "%s: omninet_read %d: ",
197 			       __FILE__, header->oh_len);
198 			for (i = 0; i < (header->oh_len +
199 						OMNINET_HEADERLEN); i++)
200 				printk("%.2x ", data[i]);
201 			printk("\n");
202 		}
203 	}
204 
205 	if (urb->actual_length && header->oh_len) {
206 		struct tty_struct *tty = tty_port_tty_get(&port->port);
207 		tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
208 							header->oh_len);
209 		tty_flip_buffer_push(tty);
210 		tty_kref_put(tty);
211 	}
212 
213 	/* Continue trying to always read  */
214 	usb_fill_bulk_urb(urb, port->serial->dev,
215 			usb_rcvbulkpipe(port->serial->dev,
216 					port->bulk_in_endpointAddress),
217 			urb->transfer_buffer, urb->transfer_buffer_length,
218 			omninet_read_bulk_callback, port);
219 	result = usb_submit_urb(urb, GFP_ATOMIC);
220 	if (result)
221 		dev_err(&port->dev,
222 			"%s - failed resubmitting read urb, error %d\n",
223 			__func__, result);
224 }
225 
226 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
227 					const unsigned char *buf, int count)
228 {
229 	struct usb_serial *serial = port->serial;
230 	struct usb_serial_port *wport = serial->port[1];
231 
232 	struct omninet_data *od = usb_get_serial_port_data(port);
233 	struct omninet_header *header = (struct omninet_header *)
234 					wport->write_urb->transfer_buffer;
235 
236 	int			result;
237 
238 	dbg("%s - port %d", __func__, port->number);
239 
240 	if (count == 0) {
241 		dbg("%s - write request of 0 bytes", __func__);
242 		return 0;
243 	}
244 
245 	if (!test_and_clear_bit(0, &port->write_urbs_free)) {
246 		dbg("%s - already writing", __func__);
247 		return 0;
248 	}
249 
250 	count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
251 
252 	memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
253 								buf, count);
254 
255 	usb_serial_debug_data(debug, &port->dev, __func__, count,
256 					wport->write_urb->transfer_buffer);
257 
258 	header->oh_seq 	= od->od_outseq++;
259 	header->oh_len 	= count;
260 	header->oh_xxx  = 0x03;
261 	header->oh_pad 	= 0x00;
262 
263 	/* send the data out the bulk port, always 64 bytes */
264 	wport->write_urb->transfer_buffer_length = 64;
265 
266 	result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
267 	if (result) {
268 		set_bit(0, &wport->write_urbs_free);
269 		dev_err(&port->dev,
270 			"%s - failed submitting write urb, error %d\n",
271 			__func__, result);
272 	} else
273 		result = count;
274 
275 	return result;
276 }
277 
278 
279 static int omninet_write_room(struct tty_struct *tty)
280 {
281 	struct usb_serial_port *port = tty->driver_data;
282 	struct usb_serial 	*serial = port->serial;
283 	struct usb_serial_port 	*wport 	= serial->port[1];
284 
285 	int room = 0; /* Default: no room */
286 
287 	if (test_bit(0, &wport->write_urbs_free))
288 		room = wport->bulk_out_size - OMNINET_HEADERLEN;
289 
290 	dbg("%s - returns %d", __func__, room);
291 
292 	return room;
293 }
294 
295 static void omninet_write_bulk_callback(struct urb *urb)
296 {
297 /*	struct omninet_header	*header = (struct omninet_header  *)
298 						urb->transfer_buffer; */
299 	struct usb_serial_port 	*port   =  urb->context;
300 	int status = urb->status;
301 
302 	dbg("%s - port %0x", __func__, port->number);
303 
304 	set_bit(0, &port->write_urbs_free);
305 	if (status) {
306 		dbg("%s - nonzero write bulk status received: %d",
307 		    __func__, status);
308 		return;
309 	}
310 
311 	usb_serial_port_softint(port);
312 }
313 
314 
315 static void omninet_disconnect(struct usb_serial *serial)
316 {
317 	struct usb_serial_port *wport = serial->port[1];
318 
319 	dbg("%s", __func__);
320 
321 	usb_kill_urb(wport->write_urb);
322 }
323 
324 
325 static void omninet_release(struct usb_serial *serial)
326 {
327 	struct usb_serial_port *port = serial->port[0];
328 
329 	dbg("%s", __func__);
330 
331 	kfree(usb_get_serial_port_data(port));
332 }
333 
334 
335 static int __init omninet_init(void)
336 {
337 	int retval;
338 	retval = usb_serial_register(&zyxel_omninet_device);
339 	if (retval)
340 		goto failed_usb_serial_register;
341 	retval = usb_register(&omninet_driver);
342 	if (retval)
343 		goto failed_usb_register;
344 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
345 	       DRIVER_DESC "\n");
346 	return 0;
347 failed_usb_register:
348 	usb_serial_deregister(&zyxel_omninet_device);
349 failed_usb_serial_register:
350 	return retval;
351 }
352 
353 
354 static void __exit omninet_exit(void)
355 {
356 	usb_deregister(&omninet_driver);
357 	usb_serial_deregister(&zyxel_omninet_device);
358 }
359 
360 
361 module_init(omninet_init);
362 module_exit(omninet_exit);
363 
364 MODULE_AUTHOR(DRIVER_AUTHOR);
365 MODULE_DESCRIPTION(DRIVER_DESC);
366 MODULE_LICENSE("GPL");
367 
368 module_param(debug, bool, S_IRUGO | S_IWUSR);
369 MODULE_PARM_DESC(debug, "Debug enabled or not");
370