xref: /openbmc/linux/drivers/usb/serial/ipw.c (revision 545e4006)
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 = port->port.tty;
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 
180 	/* Continue trying to always read  */
181 	usb_fill_bulk_urb(port->read_urb, port->serial->dev,
182 			  usb_rcvbulkpipe(port->serial->dev,
183 					   port->bulk_in_endpointAddress),
184 			  port->read_urb->transfer_buffer,
185 			  port->read_urb->transfer_buffer_length,
186 			  ipw_read_bulk_callback, port);
187 	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
188 	if (result)
189 		dev_err(&port->dev,
190 			"%s - failed resubmitting read urb, error %d\n",
191 							__func__, result);
192 	return;
193 }
194 
195 static int ipw_open(struct tty_struct *tty,
196 			struct usb_serial_port *port, struct file *filp)
197 {
198 	struct usb_device *dev = port->serial->dev;
199 	u8 buf_flow_static[16] = IPW_BYTES_FLOWINIT;
200 	u8 *buf_flow_init;
201 	int result;
202 
203 	dbg("%s", __func__);
204 
205 	buf_flow_init = kmemdup(buf_flow_static, 16, GFP_KERNEL);
206 	if (!buf_flow_init)
207 		return -ENOMEM;
208 
209 	if (tty)
210 		tty->low_latency = 1;
211 
212 	/* --1: Tell the modem to initialize (we think) From sniffs this is
213 	 *	always the first thing that gets sent to the modem during
214 	 *	opening of the device */
215 	dbg("%s: Sending SIO_INIT (we guess)", __func__);
216 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
217 			 IPW_SIO_INIT,
218 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
219 			 0,
220 			 0, /* index */
221 			 NULL,
222 			 0,
223 			 100000);
224 	if (result < 0)
225 		dev_err(&port->dev,
226 			"Init of modem failed (error = %d)\n", result);
227 
228 	/* reset the bulk pipes */
229 	usb_clear_halt(dev,
230 			usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress));
231 	usb_clear_halt(dev,
232 			usb_sndbulkpipe(dev, port->bulk_out_endpointAddress));
233 
234 	/*--2: Start reading from the device */
235 	dbg("%s: setting up bulk read callback", __func__);
236 	usb_fill_bulk_urb(port->read_urb, dev,
237 			  usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
238 			  port->bulk_in_buffer,
239 			  port->bulk_in_size,
240 			  ipw_read_bulk_callback, port);
241 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
242 	if (result < 0)
243 		dbg("%s - usb_submit_urb(read bulk) failed with status %d",
244 							__func__, result);
245 
246 	/*--3: Tell the modem to open the floodgates on the rx bulk channel */
247 	dbg("%s:asking modem for RxRead (RXBULK_ON)", __func__);
248 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
249 			 IPW_SIO_RXCTL,
250 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
251 			 IPW_RXBULK_ON,
252 			 0, /* index */
253 			 NULL,
254 			 0,
255 			 100000);
256 	if (result < 0)
257 		dev_err(&port->dev,
258 			"Enabling bulk RxRead failed (error = %d)\n", result);
259 
260 	/*--4: setup the initial flowcontrol */
261 	dbg("%s:setting init flowcontrol (%s)", __func__, buf_flow_init);
262 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
263 			 IPW_SIO_HANDFLOW,
264 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
265 			 0,
266 			 0,
267 			 buf_flow_init,
268 			 0x10,
269 			 200000);
270 	if (result < 0)
271 		dev_err(&port->dev,
272 			"initial flowcontrol failed (error = %d)\n", result);
273 
274 
275 	/*--5: raise the dtr */
276 	dbg("%s:raising dtr", __func__);
277 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
278 			 IPW_SIO_SET_PIN,
279 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
280 			 IPW_PIN_SETDTR,
281 			 0,
282 			 NULL,
283 			 0,
284 			 200000);
285 	if (result < 0)
286 		dev_err(&port->dev,
287 				"setting dtr failed (error = %d)\n", result);
288 
289 	/*--6: raise the rts */
290 	dbg("%s:raising rts", __func__);
291 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
292 			 IPW_SIO_SET_PIN,
293 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
294 			 IPW_PIN_SETRTS,
295 			 0,
296 			 NULL,
297 			 0,
298 			 200000);
299 	if (result < 0)
300 		dev_err(&port->dev,
301 				"setting dtr failed (error = %d)\n", result);
302 
303 	kfree(buf_flow_init);
304 	return 0;
305 }
306 
307 static void ipw_close(struct tty_struct *tty,
308 			struct usb_serial_port *port, struct file *filp)
309 {
310 	struct usb_device *dev = port->serial->dev;
311 	int result;
312 
313 	if (tty_hung_up_p(filp)) {
314 		dbg("%s: tty_hung_up_p ...", __func__);
315 		return;
316 	}
317 
318 	/*--1: drop the dtr */
319 	dbg("%s:dropping dtr", __func__);
320 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
321 			 IPW_SIO_SET_PIN,
322 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
323 			 IPW_PIN_CLRDTR,
324 			 0,
325 			 NULL,
326 			 0,
327 			 200000);
328 	if (result < 0)
329 		dev_err(&port->dev, "dropping dtr failed (error = %d)\n",
330 								result);
331 
332 	/*--2: drop the rts */
333 	dbg("%s:dropping rts", __func__);
334 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
335 			 IPW_SIO_SET_PIN, USB_TYPE_VENDOR |
336 			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
337 			 IPW_PIN_CLRRTS,
338 			 0,
339 			 NULL,
340 			 0,
341 			 200000);
342 	if (result < 0)
343 		dev_err(&port->dev,
344 				"dropping rts failed (error = %d)\n", result);
345 
346 
347 	/*--3: purge */
348 	dbg("%s:sending purge", __func__);
349 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
350 			 IPW_SIO_PURGE, USB_TYPE_VENDOR |
351 			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
352 			 0x03,
353 			 0,
354 			 NULL,
355 			 0,
356 			 200000);
357 	if (result < 0)
358 		dev_err(&port->dev, "purge failed (error = %d)\n", result);
359 
360 
361 	/* send RXBULK_off (tell modem to stop transmitting bulk data on
362 	   rx chan) */
363 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
364 			 IPW_SIO_RXCTL,
365 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
366 			 IPW_RXBULK_OFF,
367 			 0, /* index */
368 			 NULL,
369 			 0,
370 			 100000);
371 
372 	if (result < 0)
373 		dev_err(&port->dev,
374 			"Disabling bulk RxRead failed (error = %d)\n", result);
375 
376 	/* shutdown any in-flight urbs that we know about */
377 	usb_kill_urb(port->read_urb);
378 	usb_kill_urb(port->write_urb);
379 }
380 
381 static void ipw_write_bulk_callback(struct urb *urb)
382 {
383 	struct usb_serial_port *port = urb->context;
384 	int status = urb->status;
385 
386 	dbg("%s", __func__);
387 
388 	port->write_urb_busy = 0;
389 
390 	if (status)
391 		dbg("%s - nonzero write bulk status received: %d",
392 		    __func__, status);
393 
394 	usb_serial_port_softint(port);
395 }
396 
397 static int ipw_write(struct tty_struct *tty, struct usb_serial_port *port,
398 					const unsigned char *buf, int count)
399 {
400 	struct usb_device *dev = port->serial->dev;
401 	int ret;
402 
403 	dbg("%s: TOP: count=%d, in_interrupt=%ld", __func__,
404 		count, in_interrupt());
405 
406 	if (count == 0) {
407 		dbg("%s - write request of 0 bytes", __func__);
408 		return 0;
409 	}
410 
411 	spin_lock_bh(&port->lock);
412 	if (port->write_urb_busy) {
413 		spin_unlock_bh(&port->lock);
414 		dbg("%s - already writing", __func__);
415 		return 0;
416 	}
417 	port->write_urb_busy = 1;
418 	spin_unlock_bh(&port->lock);
419 
420 	count = min(count, port->bulk_out_size);
421 	memcpy(port->bulk_out_buffer, buf, count);
422 
423 	dbg("%s count now:%d", __func__, count);
424 
425 	usb_fill_bulk_urb(port->write_urb, dev,
426 			  usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
427 			  port->write_urb->transfer_buffer,
428 			  count,
429 			  ipw_write_bulk_callback,
430 			  port);
431 
432 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
433 	if (ret != 0) {
434 		port->write_urb_busy = 0;
435 		dbg("%s - usb_submit_urb(write bulk) failed with error = %d",
436 								__func__, ret);
437 		return ret;
438 	}
439 
440 	dbg("%s returning %d", __func__, count);
441 	return count;
442 }
443 
444 static int ipw_probe(struct usb_serial_port *port)
445 {
446 	return 0;
447 }
448 
449 static int ipw_disconnect(struct usb_serial_port *port)
450 {
451 	usb_set_serial_port_data(port, NULL);
452 	return 0;
453 }
454 
455 static struct usb_serial_driver ipw_device = {
456 	.driver = {
457 		.owner =	THIS_MODULE,
458 		.name =		"ipw",
459 	},
460 	.description =		"IPWireless converter",
461 	.usb_driver = 		&usb_ipw_driver,
462 	.id_table =		usb_ipw_ids,
463 	.num_ports =		1,
464 	.open =			ipw_open,
465 	.close =		ipw_close,
466 	.port_probe = 		ipw_probe,
467 	.port_remove =		ipw_disconnect,
468 	.write =		ipw_write,
469 	.write_bulk_callback =	ipw_write_bulk_callback,
470 	.read_bulk_callback =	ipw_read_bulk_callback,
471 };
472 
473 
474 
475 static int usb_ipw_init(void)
476 {
477 	int retval;
478 
479 	retval = usb_serial_register(&ipw_device);
480 	if (retval)
481 		return retval;
482 	retval = usb_register(&usb_ipw_driver);
483 	if (retval) {
484 		usb_serial_deregister(&ipw_device);
485 		return retval;
486 	}
487 	info(DRIVER_DESC " " DRIVER_VERSION);
488 	return 0;
489 }
490 
491 static void usb_ipw_exit(void)
492 {
493 	usb_deregister(&usb_ipw_driver);
494 	usb_serial_deregister(&ipw_device);
495 }
496 
497 module_init(usb_ipw_init);
498 module_exit(usb_ipw_exit);
499 
500 /* Module information */
501 MODULE_AUTHOR(DRIVER_AUTHOR);
502 MODULE_DESCRIPTION(DRIVER_DESC);
503 MODULE_LICENSE("GPL");
504 
505 module_param(debug, bool, S_IRUGO | S_IWUSR);
506 MODULE_PARM_DESC(debug, "Debug enabled or not");
507