xref: /openbmc/linux/drivers/usb/serial/ipw.c (revision 78c99ba1)
1 /*
2  * IPWireless 3G UMTS TDD Modem driver (USB connected)
3  *
4  *   Copyright (C) 2004 Roelf Diedericks <roelfd@inet.co.za>
5  *   Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  * All information about the device was acquired using SnoopyPro
13  * on MSFT's O/S, and examing the MSFT drivers' debug output
14  * (insanely left _on_ in the enduser version)
15  *
16  * It was written out of frustration with the IPWireless USB modem
17  * supplied by Axity3G/Sentech South Africa not supporting
18  * Linux whatsoever.
19  *
20  * Nobody provided any proprietary information that was not already
21  * available for this device.
22  *
23  * The modem adheres to the "3GPP TS  27.007 AT command set for 3G
24  * User Equipment (UE)" standard, available from
25  * http://www.3gpp.org/ftp/Specs/html-info/27007.htm
26  *
27  * The code was only tested the IPWireless handheld modem distributed
28  * in South Africa by Sentech.
29  *
30  * It may work for Woosh Inc in .nz too, as it appears they use the
31  * same kit.
32  *
33  * There is still some work to be done in terms of handling
34  * DCD, DTR, RTS, CTS which are currently faked.
35  * It's good enough for PPP at this point. It's based off all kinds of
36  * code found in usb/serial and usb/class
37  *
38  */
39 
40 #include <linux/kernel.h>
41 #include <linux/errno.h>
42 #include <linux/init.h>
43 #include <linux/slab.h>
44 #include <linux/tty.h>
45 #include <linux/tty_flip.h>
46 #include <linux/module.h>
47 #include <linux/spinlock.h>
48 #include <linux/usb.h>
49 #include <linux/usb/serial.h>
50 #include <linux/uaccess.h>
51 
52 /*
53  * Version Information
54  */
55 #define DRIVER_VERSION	"v0.3"
56 #define DRIVER_AUTHOR	"Roelf Diedericks"
57 #define DRIVER_DESC	"IPWireless tty driver"
58 
59 #define IPW_TTY_MAJOR	240	/* real device node major id, experimental range */
60 #define IPW_TTY_MINORS	256	/* we support 256 devices, dunno why, it'd be insane :) */
61 
62 #define USB_IPW_MAGIC	0x6d02	/* magic number for ipw struct */
63 
64 
65 /* Message sizes */
66 #define EVENT_BUFFER_SIZE	0xFF
67 #define CHAR2INT16(c1, c0)	(((u32)((c1) & 0xff) << 8) + (u32)((c0) & 0xff))
68 #define NUM_BULK_URBS		24
69 #define NUM_CONTROL_URBS	16
70 
71 /* vendor/product pairs that are known work with this driver*/
72 #define IPW_VID		0x0bc3
73 #define IPW_PID		0x0001
74 
75 
76 /* Vendor commands: */
77 
78 /* baud rates */
79 enum {
80 	ipw_sio_b256000 = 0x000e,
81 	ipw_sio_b128000 = 0x001d,
82 	ipw_sio_b115200 = 0x0020,
83 	ipw_sio_b57600  = 0x0040,
84 	ipw_sio_b56000  = 0x0042,
85 	ipw_sio_b38400  = 0x0060,
86 	ipw_sio_b19200  = 0x00c0,
87 	ipw_sio_b14400  = 0x0100,
88 	ipw_sio_b9600   = 0x0180,
89 	ipw_sio_b4800   = 0x0300,
90 	ipw_sio_b2400   = 0x0600,
91 	ipw_sio_b1200   = 0x0c00,
92 	ipw_sio_b600    = 0x1800
93 };
94 
95 /* data bits */
96 #define ipw_dtb_7		0x700
97 #define ipw_dtb_8		0x810	/* ok so the define is misleading, I know, but forces 8,n,1 */
98 					/* I mean, is there a point to any other setting these days? :) */
99 
100 /* usb control request types : */
101 #define IPW_SIO_RXCTL		0x00	/* control bulk rx channel transmissions, value=1/0 (on/off) */
102 #define IPW_SIO_SET_BAUD	0x01	/* set baud, value=requested ipw_sio_bxxxx */
103 #define IPW_SIO_SET_LINE	0x03	/* set databits, parity. value=ipw_dtb_x */
104 #define IPW_SIO_SET_PIN		0x03	/* set/clear dtr/rts value=ipw_pin_xxx */
105 #define IPW_SIO_POLL		0x08	/* get serial port status byte, call with value=0 */
106 #define IPW_SIO_INIT		0x11	/* initializes ? value=0 (appears as first thing todo on open) */
107 #define IPW_SIO_PURGE		0x12	/* purge all transmissions?, call with value=numchar_to_purge */
108 #define IPW_SIO_HANDFLOW	0x13	/* set xon/xoff limits value=0, and a buffer of 0x10 bytes */
109 #define IPW_SIO_SETCHARS	0x13	/* set the flowcontrol special chars, value=0, buf=6 bytes, */
110 					/* last 2 bytes contain flowcontrol chars e.g. 00 00 00 00 11 13 */
111 
112 /* values used for request IPW_SIO_SET_PIN */
113 #define IPW_PIN_SETDTR		0x101
114 #define IPW_PIN_SETRTS		0x202
115 #define IPW_PIN_CLRDTR		0x100
116 #define IPW_PIN_CLRRTS		0x200 /* unconfirmed */
117 
118 /* values used for request IPW_SIO_RXCTL */
119 #define IPW_RXBULK_ON		1
120 #define IPW_RXBULK_OFF		0
121 
122 /* various 16 byte hardcoded transferbuffers used by flow control */
123 #define IPW_BYTES_FLOWINIT	{ 0x01, 0, 0, 0, 0x40, 0, 0, 0, \
124 					0, 0, 0, 0, 0, 0, 0, 0 }
125 
126 /* Interpretation of modem status lines */
127 /* These need sorting out by individually connecting pins and checking
128  * results. FIXME!
129  * When data is being sent we see 0x30 in the lower byte; this must
130  * contain DSR and CTS ...
131  */
132 #define IPW_DSR			((1<<4) | (1<<5))
133 #define IPW_CTS			((1<<5) | (1<<4))
134 
135 #define IPW_WANTS_TO_SEND	0x30
136 
137 static struct usb_device_id usb_ipw_ids[] = {
138 	{ USB_DEVICE(IPW_VID, IPW_PID) },
139 	{ },
140 };
141 
142 MODULE_DEVICE_TABLE(usb, usb_ipw_ids);
143 
144 static struct usb_driver usb_ipw_driver = {
145 	.name =		"ipwtty",
146 	.probe =	usb_serial_probe,
147 	.disconnect =	usb_serial_disconnect,
148 	.id_table =	usb_ipw_ids,
149 	.no_dynamic_id = 	1,
150 };
151 
152 static int debug;
153 
154 static void ipw_read_bulk_callback(struct urb *urb)
155 {
156 	struct usb_serial_port *port = urb->context;
157 	unsigned char *data = urb->transfer_buffer;
158 	struct tty_struct *tty;
159 	int result;
160 	int status = urb->status;
161 
162 	dbg("%s - port %d", __func__, port->number);
163 
164 	if (status) {
165 		dbg("%s - nonzero read bulk status received: %d",
166 		    __func__, status);
167 		return;
168 	}
169 
170 	usb_serial_debug_data(debug, &port->dev, __func__,
171 					urb->actual_length, data);
172 
173 	tty = tty_port_tty_get(&port->port);
174 	if (tty && urb->actual_length) {
175 		tty_buffer_request_room(tty, urb->actual_length);
176 		tty_insert_flip_string(tty, data, urb->actual_length);
177 		tty_flip_buffer_push(tty);
178 	}
179 	tty_kref_put(tty);
180 
181 	/* Continue trying to always read  */
182 	usb_fill_bulk_urb(port->read_urb, port->serial->dev,
183 			  usb_rcvbulkpipe(port->serial->dev,
184 					   port->bulk_in_endpointAddress),
185 			  port->read_urb->transfer_buffer,
186 			  port->read_urb->transfer_buffer_length,
187 			  ipw_read_bulk_callback, port);
188 	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
189 	if (result)
190 		dev_err(&port->dev,
191 			"%s - failed resubmitting read urb, error %d\n",
192 							__func__, result);
193 	return;
194 }
195 
196 static int ipw_open(struct tty_struct *tty,
197 			struct usb_serial_port *port, struct file *filp)
198 {
199 	struct usb_device *dev = port->serial->dev;
200 	u8 buf_flow_static[16] = IPW_BYTES_FLOWINIT;
201 	u8 *buf_flow_init;
202 	int result;
203 
204 	dbg("%s", __func__);
205 
206 	buf_flow_init = kmemdup(buf_flow_static, 16, GFP_KERNEL);
207 	if (!buf_flow_init)
208 		return -ENOMEM;
209 
210 	/* --1: Tell the modem to initialize (we think) From sniffs this is
211 	 *	always the first thing that gets sent to the modem during
212 	 *	opening of the device */
213 	dbg("%s: Sending SIO_INIT (we guess)", __func__);
214 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
215 			 IPW_SIO_INIT,
216 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
217 			 0,
218 			 0, /* index */
219 			 NULL,
220 			 0,
221 			 100000);
222 	if (result < 0)
223 		dev_err(&port->dev,
224 			"Init of modem failed (error = %d)\n", result);
225 
226 	/* reset the bulk pipes */
227 	usb_clear_halt(dev,
228 			usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress));
229 	usb_clear_halt(dev,
230 			usb_sndbulkpipe(dev, port->bulk_out_endpointAddress));
231 
232 	/*--2: Start reading from the device */
233 	dbg("%s: setting up bulk read callback", __func__);
234 	usb_fill_bulk_urb(port->read_urb, dev,
235 			  usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
236 			  port->bulk_in_buffer,
237 			  port->bulk_in_size,
238 			  ipw_read_bulk_callback, port);
239 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
240 	if (result < 0)
241 		dbg("%s - usb_submit_urb(read bulk) failed with status %d",
242 							__func__, result);
243 
244 	/*--3: Tell the modem to open the floodgates on the rx bulk channel */
245 	dbg("%s:asking modem for RxRead (RXBULK_ON)", __func__);
246 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
247 			 IPW_SIO_RXCTL,
248 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
249 			 IPW_RXBULK_ON,
250 			 0, /* index */
251 			 NULL,
252 			 0,
253 			 100000);
254 	if (result < 0)
255 		dev_err(&port->dev,
256 			"Enabling bulk RxRead failed (error = %d)\n", result);
257 
258 	/*--4: setup the initial flowcontrol */
259 	dbg("%s:setting init flowcontrol (%s)", __func__, buf_flow_init);
260 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
261 			 IPW_SIO_HANDFLOW,
262 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
263 			 0,
264 			 0,
265 			 buf_flow_init,
266 			 0x10,
267 			 200000);
268 	if (result < 0)
269 		dev_err(&port->dev,
270 			"initial flowcontrol failed (error = %d)\n", result);
271 
272 
273 	/*--5: raise the dtr */
274 	dbg("%s:raising dtr", __func__);
275 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
276 			 IPW_SIO_SET_PIN,
277 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
278 			 IPW_PIN_SETDTR,
279 			 0,
280 			 NULL,
281 			 0,
282 			 200000);
283 	if (result < 0)
284 		dev_err(&port->dev,
285 				"setting dtr failed (error = %d)\n", result);
286 
287 	/*--6: raise the rts */
288 	dbg("%s:raising rts", __func__);
289 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
290 			 IPW_SIO_SET_PIN,
291 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
292 			 IPW_PIN_SETRTS,
293 			 0,
294 			 NULL,
295 			 0,
296 			 200000);
297 	if (result < 0)
298 		dev_err(&port->dev,
299 				"setting dtr failed (error = %d)\n", result);
300 
301 	kfree(buf_flow_init);
302 	return 0;
303 }
304 
305 static void ipw_dtr_rts(struct usb_serial_port *port, int on)
306 {
307 	struct usb_device *dev = port->serial->dev;
308 	int result;
309 
310 	/*--1: drop the dtr */
311 	dbg("%s:dropping dtr", __func__);
312 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
313 			 IPW_SIO_SET_PIN,
314 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
315 			 on ? IPW_PIN_SETDTR : IPW_PIN_CLRDTR,
316 			 0,
317 			 NULL,
318 			 0,
319 			 200000);
320 	if (result < 0)
321 		dev_err(&port->dev, "dropping dtr failed (error = %d)\n",
322 								result);
323 
324 	/*--2: drop the rts */
325 	dbg("%s:dropping rts", __func__);
326 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
327 			 IPW_SIO_SET_PIN, USB_TYPE_VENDOR |
328 			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
329 			 on ? IPW_PIN_SETRTS : IPW_PIN_CLRRTS,
330 			 0,
331 			 NULL,
332 			 0,
333 			 200000);
334 	if (result < 0)
335 		dev_err(&port->dev,
336 				"dropping rts failed (error = %d)\n", result);
337 }
338 
339 static void ipw_close(struct usb_serial_port *port)
340 {
341 	struct usb_device *dev = port->serial->dev;
342 	int result;
343 
344 	/*--3: purge */
345 	dbg("%s:sending purge", __func__);
346 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
347 			 IPW_SIO_PURGE, USB_TYPE_VENDOR |
348 			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
349 			 0x03,
350 			 0,
351 			 NULL,
352 			 0,
353 			 200000);
354 	if (result < 0)
355 		dev_err(&port->dev, "purge failed (error = %d)\n", result);
356 
357 
358 	/* send RXBULK_off (tell modem to stop transmitting bulk data on
359 	   rx chan) */
360 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
361 			 IPW_SIO_RXCTL,
362 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
363 			 IPW_RXBULK_OFF,
364 			 0, /* index */
365 			 NULL,
366 			 0,
367 			 100000);
368 
369 	if (result < 0)
370 		dev_err(&port->dev,
371 			"Disabling bulk RxRead failed (error = %d)\n", result);
372 
373 	/* shutdown any in-flight urbs that we know about */
374 	usb_kill_urb(port->read_urb);
375 	usb_kill_urb(port->write_urb);
376 }
377 
378 static void ipw_write_bulk_callback(struct urb *urb)
379 {
380 	struct usb_serial_port *port = urb->context;
381 	int status = urb->status;
382 
383 	dbg("%s", __func__);
384 
385 	port->write_urb_busy = 0;
386 
387 	if (status)
388 		dbg("%s - nonzero write bulk status received: %d",
389 		    __func__, status);
390 
391 	usb_serial_port_softint(port);
392 }
393 
394 static int ipw_write(struct tty_struct *tty, struct usb_serial_port *port,
395 					const unsigned char *buf, int count)
396 {
397 	struct usb_device *dev = port->serial->dev;
398 	int ret;
399 
400 	dbg("%s: TOP: count=%d, in_interrupt=%ld", __func__,
401 		count, in_interrupt());
402 
403 	if (count == 0) {
404 		dbg("%s - write request of 0 bytes", __func__);
405 		return 0;
406 	}
407 
408 	spin_lock_bh(&port->lock);
409 	if (port->write_urb_busy) {
410 		spin_unlock_bh(&port->lock);
411 		dbg("%s - already writing", __func__);
412 		return 0;
413 	}
414 	port->write_urb_busy = 1;
415 	spin_unlock_bh(&port->lock);
416 
417 	count = min(count, port->bulk_out_size);
418 	memcpy(port->bulk_out_buffer, buf, count);
419 
420 	dbg("%s count now:%d", __func__, count);
421 
422 	usb_fill_bulk_urb(port->write_urb, dev,
423 			  usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
424 			  port->write_urb->transfer_buffer,
425 			  count,
426 			  ipw_write_bulk_callback,
427 			  port);
428 
429 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
430 	if (ret != 0) {
431 		port->write_urb_busy = 0;
432 		dbg("%s - usb_submit_urb(write bulk) failed with error = %d",
433 								__func__, ret);
434 		return ret;
435 	}
436 
437 	dbg("%s returning %d", __func__, count);
438 	return count;
439 }
440 
441 static int ipw_probe(struct usb_serial_port *port)
442 {
443 	return 0;
444 }
445 
446 static int ipw_disconnect(struct usb_serial_port *port)
447 {
448 	usb_set_serial_port_data(port, NULL);
449 	return 0;
450 }
451 
452 static struct usb_serial_driver ipw_device = {
453 	.driver = {
454 		.owner =	THIS_MODULE,
455 		.name =		"ipw",
456 	},
457 	.description =		"IPWireless converter",
458 	.usb_driver = 		&usb_ipw_driver,
459 	.id_table =		usb_ipw_ids,
460 	.num_ports =		1,
461 	.open =			ipw_open,
462 	.close =		ipw_close,
463 	.dtr_rts =		ipw_dtr_rts,
464 	.port_probe = 		ipw_probe,
465 	.port_remove =		ipw_disconnect,
466 	.write =		ipw_write,
467 	.write_bulk_callback =	ipw_write_bulk_callback,
468 	.read_bulk_callback =	ipw_read_bulk_callback,
469 };
470 
471 
472 
473 static int __init usb_ipw_init(void)
474 {
475 	int retval;
476 
477 	retval = usb_serial_register(&ipw_device);
478 	if (retval)
479 		return retval;
480 	retval = usb_register(&usb_ipw_driver);
481 	if (retval) {
482 		usb_serial_deregister(&ipw_device);
483 		return retval;
484 	}
485 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
486 	       DRIVER_DESC "\n");
487 	return 0;
488 }
489 
490 static void __exit usb_ipw_exit(void)
491 {
492 	usb_deregister(&usb_ipw_driver);
493 	usb_serial_deregister(&ipw_device);
494 }
495 
496 module_init(usb_ipw_init);
497 module_exit(usb_ipw_exit);
498 
499 /* Module information */
500 MODULE_AUTHOR(DRIVER_AUTHOR);
501 MODULE_DESCRIPTION(DRIVER_DESC);
502 MODULE_LICENSE("GPL");
503 
504 module_param(debug, bool, S_IRUGO | S_IWUSR);
505 MODULE_PARM_DESC(debug, "Debug enabled or not");
506