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/drivers/usb/serial/omninet.c

https://bitbucket.org/cyanogenmod/android_kernel_asus_tf300t
C | 400 lines | 262 code | 68 blank | 70 comment | 19 complexity | 221ca1c33049461b35a5162655aec26e MD5 | raw file
Possible License(s): LGPL-2.0, AGPL-1.0, GPL-2.0
  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 * (05/30/2001) gkh
 14 *	switched from using spinlock to a semaphore, which fixes lots of
 15 *	problems.
 16 *
 17 * (04/08/2001) gb
 18 *	Identify version on module load.
 19 *
 20 * (11/01/2000) Adam J. Richter
 21 *	usb_device_id table support
 22 *
 23 * (10/05/2000) gkh
 24 *	Fixed bug with urb->dev not being set properly, now that the usb
 25 *	core needs it.
 26 *
 27 * (08/28/2000) gkh
 28 *	Added locks for SMP safeness.
 29 *	Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
 30 *	than once.
 31 *	Fixed potential race in omninet_write_bulk_callback
 32 *
 33 * (07/19/2000) gkh
 34 *	Added module_init and module_exit functions to handle the fact that this
 35 *	driver is a loadable module now.
 36 *
 37 */
 38
 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 <linux/uaccess.h>
 49#include <linux/usb.h>
 50#include <linux/usb/serial.h>
 51
 52static 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/* This one seems to be a re-branded ZyXEL device */
 64#define BT_IGNITIONPRO_ID	0x2000
 65
 66/* function prototypes */
 67static int  omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
 68static void omninet_close(struct usb_serial_port *port);
 69static void omninet_read_bulk_callback(struct urb *urb);
 70static void omninet_write_bulk_callback(struct urb *urb);
 71static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
 72				const unsigned char *buf, int count);
 73static int  omninet_write_room(struct tty_struct *tty);
 74static void omninet_disconnect(struct usb_serial *serial);
 75static void omninet_release(struct usb_serial *serial);
 76static int omninet_attach(struct usb_serial *serial);
 77
 78static const struct usb_device_id id_table[] = {
 79	{ USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
 80	{ USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
 81	{ }						/* Terminating entry */
 82};
 83
 84MODULE_DEVICE_TABLE(usb, id_table);
 85
 86static struct usb_driver omninet_driver = {
 87	.name =		"omninet",
 88	.probe =	usb_serial_probe,
 89	.disconnect =	usb_serial_disconnect,
 90	.id_table =	id_table,
 91	.no_dynamic_id = 	1,
 92};
 93
 94
 95static struct usb_serial_driver zyxel_omninet_device = {
 96	.driver = {
 97		.owner =	THIS_MODULE,
 98		.name =		"omninet",
 99	},
100	.description =		"ZyXEL - omni.net lcd plus usb",
101	.usb_driver =		&omninet_driver,
102	.id_table =		id_table,
103	.num_ports =		1,
104	.attach =		omninet_attach,
105	.open =			omninet_open,
106	.close =		omninet_close,
107	.write =		omninet_write,
108	.write_room =		omninet_write_room,
109	.read_bulk_callback =	omninet_read_bulk_callback,
110	.write_bulk_callback =	omninet_write_bulk_callback,
111	.disconnect =		omninet_disconnect,
112	.release =		omninet_release,
113};
114
115
116/* The protocol.
117 *
118 * The omni.net always exchange 64 bytes of data with the host. The first
119 * four bytes are the control header, you can see it in the above structure.
120 *
121 * oh_seq is a sequence number. Don't know if/how it's used.
122 * oh_len is the length of the data bytes in the packet.
123 * oh_xxx Bit-mapped, related to handshaking and status info.
124 *	I normally set it to 0x03 in trasmitted frames.
125 *	7: Active when the TA is in a CONNECTed state.
126 *	6: unknown
127 *	5: handshaking, unknown
128 *	4: handshaking, unknown
129 *	3: unknown, usually 0
130 *	2: unknown, usually 0
131 *	1: handshaking, unknown, usually set to 1 in trasmitted frames
132 *	0: handshaking, unknown, usually set to 1 in trasmitted frames
133 * oh_pad Probably a pad byte.
134 *
135 * After the header you will find data bytes if oh_len was greater than zero.
136 *
137 */
138
139struct omninet_header {
140	__u8	oh_seq;
141	__u8	oh_len;
142	__u8	oh_xxx;
143	__u8	oh_pad;
144};
145
146struct omninet_data {
147	__u8	od_outseq;	/* Sequence number for bulk_out URBs */
148};
149
150static 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		dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n",
158			__func__, sizeof(struct omninet_data));
159		return -ENOMEM;
160	}
161	usb_set_serial_port_data(port, od);
162	return 0;
163}
164
165static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port)
166{
167	struct usb_serial	*serial = port->serial;
168	struct usb_serial_port	*wport;
169	int			result = 0;
170
171	dbg("%s - port %d", __func__, port->number);
172
173	wport = serial->port[1];
174	tty_port_tty_set(&wport->port, tty);
175
176	/* Start reading from the device */
177	usb_fill_bulk_urb(port->read_urb, serial->dev,
178			usb_rcvbulkpipe(serial->dev,
179				port->bulk_in_endpointAddress),
180			port->read_urb->transfer_buffer,
181			port->read_urb->transfer_buffer_length,
182			omninet_read_bulk_callback, port);
183	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
184	if (result)
185		dev_err(&port->dev,
186			"%s - failed submitting read urb, error %d\n",
187			__func__, result);
188	return result;
189}
190
191static void omninet_close(struct usb_serial_port *port)
192{
193	dbg("%s - port %d", __func__, port->number);
194	usb_kill_urb(port->read_urb);
195}
196
197
198#define OMNINET_DATAOFFSET	0x04
199#define OMNINET_HEADERLEN	sizeof(struct omninet_header)
200#define OMNINET_BULKOUTSIZE 	(64 - OMNINET_HEADERLEN)
201
202static void omninet_read_bulk_callback(struct urb *urb)
203{
204	struct usb_serial_port 	*port 	= urb->context;
205	unsigned char 		*data 	= urb->transfer_buffer;
206	struct omninet_header 	*header = (struct omninet_header *) &data[0];
207	int status = urb->status;
208	int result;
209	int i;
210
211	dbg("%s - port %d", __func__, port->number);
212
213	if (status) {
214		dbg("%s - nonzero read bulk status received: %d",
215		    __func__, status);
216		return;
217	}
218
219	if (debug && header->oh_xxx != 0x30) {
220		if (urb->actual_length) {
221			printk(KERN_DEBUG "%s: omninet_read %d: ",
222			       __FILE__, header->oh_len);
223			for (i = 0; i < (header->oh_len +
224						OMNINET_HEADERLEN); i++)
225				printk("%.2x ", data[i]);
226			printk("\n");
227		}
228	}
229
230	if (urb->actual_length && header->oh_len) {
231		struct tty_struct *tty = tty_port_tty_get(&port->port);
232		tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
233							header->oh_len);
234		tty_flip_buffer_push(tty);
235		tty_kref_put(tty);
236	}
237
238	/* Continue trying to always read  */
239	usb_fill_bulk_urb(urb, port->serial->dev,
240			usb_rcvbulkpipe(port->serial->dev,
241					port->bulk_in_endpointAddress),
242			urb->transfer_buffer, urb->transfer_buffer_length,
243			omninet_read_bulk_callback, port);
244	result = usb_submit_urb(urb, GFP_ATOMIC);
245	if (result)
246		dev_err(&port->dev,
247			"%s - failed resubmitting read urb, error %d\n",
248			__func__, result);
249}
250
251static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
252					const unsigned char *buf, int count)
253{
254	struct usb_serial *serial = port->serial;
255	struct usb_serial_port *wport = serial->port[1];
256
257	struct omninet_data *od = usb_get_serial_port_data(port);
258	struct omninet_header *header = (struct omninet_header *)
259					wport->write_urb->transfer_buffer;
260
261	int			result;
262
263	dbg("%s - port %d", __func__, port->number);
264
265	if (count == 0) {
266		dbg("%s - write request of 0 bytes", __func__);
267		return 0;
268	}
269
270	spin_lock_bh(&wport->lock);
271	if (wport->write_urb_busy) {
272		spin_unlock_bh(&wport->lock);
273		dbg("%s - already writing", __func__);
274		return 0;
275	}
276	wport->write_urb_busy = 1;
277	spin_unlock_bh(&wport->lock);
278
279	count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
280
281	memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
282								buf, count);
283
284	usb_serial_debug_data(debug, &port->dev, __func__, count,
285					wport->write_urb->transfer_buffer);
286
287	header->oh_seq 	= od->od_outseq++;
288	header->oh_len 	= count;
289	header->oh_xxx  = 0x03;
290	header->oh_pad 	= 0x00;
291
292	/* send the data out the bulk port, always 64 bytes */
293	wport->write_urb->transfer_buffer_length = 64;
294
295	wport->write_urb->dev = serial->dev;
296	result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
297	if (result) {
298		wport->write_urb_busy = 0;
299		dev_err(&port->dev,
300			"%s - failed submitting write urb, error %d\n",
301			__func__, result);
302	} else
303		result = count;
304
305	return result;
306}
307
308
309static int omninet_write_room(struct tty_struct *tty)
310{
311	struct usb_serial_port *port = tty->driver_data;
312	struct usb_serial 	*serial = port->serial;
313	struct usb_serial_port 	*wport 	= serial->port[1];
314
315	int room = 0; /* Default: no room */
316
317	/* FIXME: no consistent locking for write_urb_busy */
318	if (!wport->write_urb_busy)
319		room = wport->bulk_out_size - OMNINET_HEADERLEN;
320
321	dbg("%s - returns %d", __func__, room);
322
323	return room;
324}
325
326static void omninet_write_bulk_callback(struct urb *urb)
327{
328/*	struct omninet_header	*header = (struct omninet_header  *)
329						urb->transfer_buffer; */
330	struct usb_serial_port 	*port   =  urb->context;
331	int status = urb->status;
332
333	dbg("%s - port %0x", __func__, port->number);
334
335	port->write_urb_busy = 0;
336	if (status) {
337		dbg("%s - nonzero write bulk status received: %d",
338		    __func__, status);
339		return;
340	}
341
342	usb_serial_port_softint(port);
343}
344
345
346static void omninet_disconnect(struct usb_serial *serial)
347{
348	struct usb_serial_port *wport = serial->port[1];
349
350	dbg("%s", __func__);
351
352	usb_kill_urb(wport->write_urb);
353}
354
355
356static void omninet_release(struct usb_serial *serial)
357{
358	struct usb_serial_port *port = serial->port[0];
359
360	dbg("%s", __func__);
361
362	kfree(usb_get_serial_port_data(port));
363}
364
365
366static int __init omninet_init(void)
367{
368	int retval;
369	retval = usb_serial_register(&zyxel_omninet_device);
370	if (retval)
371		goto failed_usb_serial_register;
372	retval = usb_register(&omninet_driver);
373	if (retval)
374		goto failed_usb_register;
375	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
376	       DRIVER_DESC "\n");
377	return 0;
378failed_usb_register:
379	usb_serial_deregister(&zyxel_omninet_device);
380failed_usb_serial_register:
381	return retval;
382}
383
384
385static void __exit omninet_exit(void)
386{
387	usb_deregister(&omninet_driver);
388	usb_serial_deregister(&zyxel_omninet_device);
389}
390
391
392module_init(omninet_init);
393module_exit(omninet_exit);
394
395MODULE_AUTHOR(DRIVER_AUTHOR);
396MODULE_DESCRIPTION(DRIVER_DESC);
397MODULE_LICENSE("GPL");
398
399module_param(debug, bool, S_IRUGO | S_IWUSR);
400MODULE_PARM_DESC(debug, "Debug enabled or not");