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
26static bool 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 */
41static int  omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
42static void omninet_close(struct usb_serial_port *port);
43static void omninet_read_bulk_callback(struct urb *urb);
44static void omninet_write_bulk_callback(struct urb *urb);
45static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
46				const unsigned char *buf, int count);
47static int  omninet_write_room(struct tty_struct *tty);
48static void omninet_disconnect(struct usb_serial *serial);
49static void omninet_release(struct usb_serial *serial);
50static int omninet_attach(struct usb_serial *serial);
51
52static 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
58MODULE_DEVICE_TABLE(usb, id_table);
59
60static 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
69static 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
113struct omninet_header {
114	__u8	oh_seq;
115	__u8	oh_len;
116	__u8	oh_xxx;
117	__u8	oh_pad;
118};
119
120struct omninet_data {
121	__u8	od_outseq;	/* Sequence number for bulk_out URBs */
122};
123
124static 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
139static 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	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
152	if (result)
153		dev_err(&port->dev,
154			"%s - failed submitting read urb, error %d\n",
155			__func__, result);
156	return result;
157}
158
159static void omninet_close(struct usb_serial_port *port)
160{
161	dbg("%s - port %d", __func__, port->number);
162	usb_kill_urb(port->read_urb);
163}
164
165
166#define OMNINET_DATAOFFSET	0x04
167#define OMNINET_HEADERLEN	sizeof(struct omninet_header)
168#define OMNINET_BULKOUTSIZE 	(64 - OMNINET_HEADERLEN)
169
170static void omninet_read_bulk_callback(struct urb *urb)
171{
172	struct usb_serial_port 	*port 	= urb->context;
173	unsigned char 		*data 	= urb->transfer_buffer;
174	struct omninet_header 	*header = (struct omninet_header *) &data[0];
175	int status = urb->status;
176	int result;
177	int i;
178
179	dbg("%s - port %d", __func__, port->number);
180
181	if (status) {
182		dbg("%s - nonzero read bulk status received: %d",
183		    __func__, status);
184		return;
185	}
186
187	if (debug && header->oh_xxx != 0x30) {
188		if (urb->actual_length) {
189			printk(KERN_DEBUG "%s: omninet_read %d: ",
190			       __FILE__, header->oh_len);
191			for (i = 0; i < (header->oh_len +
192						OMNINET_HEADERLEN); i++)
193				printk("%.2x ", data[i]);
194			printk("\n");
195		}
196	}
197
198	if (urb->actual_length && header->oh_len) {
199		struct tty_struct *tty = tty_port_tty_get(&port->port);
200		tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
201							header->oh_len);
202		tty_flip_buffer_push(tty);
203		tty_kref_put(tty);
204	}
205
206	/* Continue trying to always read  */
207	result = usb_submit_urb(urb, GFP_ATOMIC);
208	if (result)
209		dev_err(&port->dev,
210			"%s - failed resubmitting read urb, error %d\n",
211			__func__, result);
212}
213
214static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
215					const unsigned char *buf, int count)
216{
217	struct usb_serial *serial = port->serial;
218	struct usb_serial_port *wport = serial->port[1];
219
220	struct omninet_data *od = usb_get_serial_port_data(port);
221	struct omninet_header *header = (struct omninet_header *)
222					wport->write_urb->transfer_buffer;
223
224	int			result;
225
226	dbg("%s - port %d", __func__, port->number);
227
228	if (count == 0) {
229		dbg("%s - write request of 0 bytes", __func__);
230		return 0;
231	}
232
233	if (!test_and_clear_bit(0, &port->write_urbs_free)) {
234		dbg("%s - already writing", __func__);
235		return 0;
236	}
237
238	count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
239
240	memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
241								buf, count);
242
243	usb_serial_debug_data(debug, &port->dev, __func__, count,
244					wport->write_urb->transfer_buffer);
245
246	header->oh_seq 	= od->od_outseq++;
247	header->oh_len 	= count;
248	header->oh_xxx  = 0x03;
249	header->oh_pad 	= 0x00;
250
251	/* send the data out the bulk port, always 64 bytes */
252	wport->write_urb->transfer_buffer_length = 64;
253
254	result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
255	if (result) {
256		set_bit(0, &wport->write_urbs_free);
257		dev_err(&port->dev,
258			"%s - failed submitting write urb, error %d\n",
259			__func__, result);
260	} else
261		result = count;
262
263	return result;
264}
265
266
267static int omninet_write_room(struct tty_struct *tty)
268{
269	struct usb_serial_port *port = tty->driver_data;
270	struct usb_serial 	*serial = port->serial;
271	struct usb_serial_port 	*wport 	= serial->port[1];
272
273	int room = 0; /* Default: no room */
274
275	if (test_bit(0, &wport->write_urbs_free))
276		room = wport->bulk_out_size - OMNINET_HEADERLEN;
277
278	dbg("%s - returns %d", __func__, room);
279
280	return room;
281}
282
283static void omninet_write_bulk_callback(struct urb *urb)
284{
285/*	struct omninet_header	*header = (struct omninet_header  *)
286						urb->transfer_buffer; */
287	struct usb_serial_port 	*port   =  urb->context;
288	int status = urb->status;
289
290	dbg("%s - port %0x", __func__, port->number);
291
292	set_bit(0, &port->write_urbs_free);
293	if (status) {
294		dbg("%s - nonzero write bulk status received: %d",
295		    __func__, status);
296		return;
297	}
298
299	usb_serial_port_softint(port);
300}
301
302
303static void omninet_disconnect(struct usb_serial *serial)
304{
305	struct usb_serial_port *wport = serial->port[1];
306
307	dbg("%s", __func__);
308
309	usb_kill_urb(wport->write_urb);
310}
311
312
313static void omninet_release(struct usb_serial *serial)
314{
315	struct usb_serial_port *port = serial->port[0];
316
317	dbg("%s", __func__);
318
319	kfree(usb_get_serial_port_data(port));
320}
321
322
323static int __init omninet_init(void)
324{
325	int retval;
326	retval = usb_serial_register(&zyxel_omninet_device);
327	if (retval)
328		goto failed_usb_serial_register;
329	retval = usb_register(&omninet_driver);
330	if (retval)
331		goto failed_usb_register;
332	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
333	       DRIVER_DESC "\n");
334	return 0;
335failed_usb_register:
336	usb_serial_deregister(&zyxel_omninet_device);
337failed_usb_serial_register:
338	return retval;
339}
340
341
342static void __exit omninet_exit(void)
343{
344	usb_deregister(&omninet_driver);
345	usb_serial_deregister(&zyxel_omninet_device);
346}
347
348
349module_init(omninet_init);
350module_exit(omninet_exit);
351
352MODULE_AUTHOR(DRIVER_AUTHOR);
353MODULE_DESCRIPTION(DRIVER_DESC);
354MODULE_LICENSE("GPL");
355
356module_param(debug, bool, S_IRUGO | S_IWUSR);
357MODULE_PARM_DESC(debug, "Debug enabled or not");
358