xref: /openbmc/linux/drivers/usb/serial/ipw.c (revision 1da177e4)
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.h>
50 #include <asm/uaccess.h>
51 #include "usb-serial.h"
52 
53 /*
54  * Version Information
55  */
56 #define DRIVER_VERSION	"v0.3"
57 #define DRIVER_AUTHOR	"Roelf Diedericks"
58 #define DRIVER_DESC	"IPWireless tty driver"
59 
60 #define IPW_TTY_MAJOR	240	/* real device node major id, experimental range */
61 #define IPW_TTY_MINORS	256	/* we support 256 devices, dunno why, it'd be insane :) */
62 
63 #define USB_IPW_MAGIC	0x6d02	/* magic number for ipw struct */
64 
65 
66 /* Message sizes */
67 #define EVENT_BUFFER_SIZE	0xFF
68 #define CHAR2INT16(c1,c0)	(((u32)((c1) & 0xff) << 8) + (u32)((c0) & 0xff))
69 #define NUM_BULK_URBS		24
70 #define NUM_CONTROL_URBS	16
71 
72 /* vendor/product pairs that are known work with this driver*/
73 #define IPW_VID		0x0bc3
74 #define IPW_PID		0x0001
75 
76 
77 /* Vendor commands: */
78 
79 /* baud rates */
80 enum {
81 	ipw_sio_b256000 = 0x000e,
82 	ipw_sio_b128000 = 0x001d,
83 	ipw_sio_b115200 = 0x0020,
84 	ipw_sio_b57600  = 0x0040,
85 	ipw_sio_b56000  = 0x0042,
86 	ipw_sio_b38400  = 0x0060,
87 	ipw_sio_b19200  = 0x00c0,
88 	ipw_sio_b14400  = 0x0100,
89 	ipw_sio_b9600   = 0x0180,
90 	ipw_sio_b4800   = 0x0300,
91 	ipw_sio_b2400   = 0x0600,
92 	ipw_sio_b1200   = 0x0c00,
93 	ipw_sio_b600    = 0x1800
94 };
95 
96 /* data bits */
97 #define ipw_dtb_7		0x700
98 #define ipw_dtb_8		0x810	// ok so the define is misleading, I know, but forces 8,n,1
99 					// I mean, is there a point to any other setting these days? :)
100 
101 /* usb control request types : */
102 #define IPW_SIO_RXCTL		0x00	// control bulk rx channel transmissions, value=1/0 (on/off)
103 #define IPW_SIO_SET_BAUD	0x01	// set baud, value=requested ipw_sio_bxxxx
104 #define IPW_SIO_SET_LINE	0x03	// set databits, parity. value=ipw_dtb_x
105 #define IPW_SIO_SET_PIN		0x03	// set/clear dtr/rts value=ipw_pin_xxx
106 #define IPW_SIO_POLL		0x08	// get serial port status byte, call with value=0
107 #define IPW_SIO_INIT		0x11	// initializes ? value=0 (appears as first thing todo on open)
108 #define IPW_SIO_PURGE		0x12	// purge all transmissions?, call with value=numchar_to_purge
109 #define IPW_SIO_HANDFLOW	0x13	// set xon/xoff limits value=0, and a buffer of 0x10 bytes
110 #define IPW_SIO_SETCHARS	0x13	// set the flowcontrol special chars, value=0, buf=6 bytes,
111 					// last 2 bytes contain flowcontrol chars e.g. 00 00 00 00 11 13
112 
113 /* values used for request IPW_SIO_SET_PIN */
114 #define IPW_PIN_SETDTR		0x101
115 #define IPW_PIN_SETRTS		0x202
116 #define IPW_PIN_CLRDTR		0x100
117 #define IPW_PIN_CLRRTS		0x200 // unconfirmed
118 
119 /* values used for request IPW_SIO_RXCTL */
120 #define IPW_RXBULK_ON		1
121 #define IPW_RXBULK_OFF		0
122 
123 /* various 16 byte hardcoded transferbuffers used by flow control */
124 #define IPW_BYTES_FLOWINIT	{ 0x01, 0, 0, 0, 0x40, 0, 0, 0, 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 //#define IPW_DTR			/* Data Terminal Ready */
137 //#define IPW_CTS			/* Clear To Send */
138 //#define IPW_CD			/* Carrier Detect */
139 //#define IPW_DSR			/* Data Set Ready */
140 //#define IPW_RxD			/* Receive pin */
141 
142 //#define IPW_LE
143 //#define IPW_RTS
144 //#define IPW_ST
145 //#define IPW_SR
146 //#define IPW_RI			/* Ring Indicator */
147 
148 static struct usb_device_id usb_ipw_ids[] = {
149 	{ USB_DEVICE(IPW_VID, IPW_PID) },
150 	{ },
151 };
152 
153 MODULE_DEVICE_TABLE(usb, usb_ipw_ids);
154 
155 static struct usb_driver usb_ipw_driver = {
156 	.owner =	THIS_MODULE,
157 	.name =		"ipwtty",
158 	.probe =	usb_serial_probe,
159 	.disconnect =	usb_serial_disconnect,
160 	.id_table =	usb_ipw_ids,
161 };
162 
163 static int debug;
164 
165 static void ipw_read_bulk_callback(struct urb *urb, struct pt_regs *regs)
166 {
167 	struct usb_serial_port *port = urb->context;
168 	unsigned char *data = urb->transfer_buffer;
169 	struct tty_struct *tty;
170 	int i;
171 	int result;
172 
173 	dbg("%s - port %d", __FUNCTION__, port->number);
174 
175 	if (urb->status) {
176 		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
177 		return;
178 	}
179 
180 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
181 
182 	tty = port->tty;
183 	if (tty && urb->actual_length) {
184 		for (i = 0; i < urb->actual_length ; ++i) {
185 			/* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
186 			if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
187 				tty_flip_buffer_push(tty);
188 			}
189 			/* this doesn't actually push the data through unless tty->low_latency is set */
190 			tty_insert_flip_char(tty, data[i], 0);
191 		}
192 		tty_flip_buffer_push(tty);
193 	}
194 
195 	/* Continue trying to always read  */
196 	usb_fill_bulk_urb (port->read_urb, port->serial->dev,
197 			   usb_rcvbulkpipe(port->serial->dev,
198 					   port->bulk_in_endpointAddress),
199 			   port->read_urb->transfer_buffer,
200 			   port->read_urb->transfer_buffer_length,
201 			   ipw_read_bulk_callback, port);
202 	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
203 	if (result)
204 		dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
205 	return;
206 }
207 
208 static int ipw_open(struct usb_serial_port *port, struct file *filp)
209 {
210 	struct usb_device *dev = port->serial->dev;
211 	u8 buf_flow_static[16] = IPW_BYTES_FLOWINIT;
212 	u8 *buf_flow_init;
213 	int result;
214 
215 	dbg("%s", __FUNCTION__);
216 
217 	buf_flow_init = kmalloc(16, GFP_KERNEL);
218 	if (!buf_flow_init)
219 		return -ENOMEM;
220 	memcpy(buf_flow_init, buf_flow_static, 16);
221 
222 	if (port->tty)
223 		port->tty->low_latency = 1;
224 
225 	/* --1: Tell the modem to initialize (we think) From sniffs this is always the
226 	 * first thing that gets sent to the modem during opening of the device */
227 	dbg("%s: Sending SIO_INIT (we guess)",__FUNCTION__);
228 	result = usb_control_msg(dev, usb_sndctrlpipe(dev,0),
229 				 IPW_SIO_INIT,
230 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
231 				 0,
232 				 0, /* index */
233 				 NULL,
234 				 0,
235 				 100000);
236 	if (result < 0)
237 		dev_err(&port->dev, "Init of modem failed (error = %d)", result);
238 
239 	/* reset the bulk pipes */
240 	usb_clear_halt(dev, usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress));
241 	usb_clear_halt(dev, usb_sndbulkpipe(dev, port->bulk_out_endpointAddress));
242 
243 	/*--2: Start reading from the device */
244 	dbg("%s: setting up bulk read callback",__FUNCTION__);
245 	usb_fill_bulk_urb(port->read_urb, dev,
246 			  usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
247 			  port->bulk_in_buffer,
248 			  port->bulk_in_size,
249 			  ipw_read_bulk_callback, port);
250 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
251 	if (result < 0)
252 		dbg("%s - usb_submit_urb(read bulk) failed with status %d", __FUNCTION__, result);
253 
254 	/*--3: Tell the modem to open the floodgates on the rx bulk channel */
255 	dbg("%s:asking modem for RxRead (RXBULK_ON)",__FUNCTION__);
256 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
257 				 IPW_SIO_RXCTL,
258 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
259 				 IPW_RXBULK_ON,
260 				 0, /* index */
261 				 NULL,
262 				 0,
263 				 100000);
264 	if (result < 0)
265 		dev_err(&port->dev, "Enabling bulk RxRead failed (error = %d)", result);
266 
267 	/*--4: setup the initial flowcontrol */
268 	dbg("%s:setting init flowcontrol (%s)",__FUNCTION__,buf_flow_init);
269 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
270 				 IPW_SIO_HANDFLOW,
271 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
272 				 0,
273 				 0,
274 				 buf_flow_init,
275 				 0x10,
276 				 200000);
277 	if (result < 0)
278 		dev_err(&port->dev, "initial flowcontrol failed (error = %d)", result);
279 
280 
281 	/*--5: raise the dtr */
282 	dbg("%s:raising dtr",__FUNCTION__);
283 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
284 				 IPW_SIO_SET_PIN,
285 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
286 				 IPW_PIN_SETDTR,
287 				 0,
288 				 NULL,
289 				 0,
290 				 200000);
291 	if (result < 0)
292 		dev_err(&port->dev, "setting dtr failed (error = %d)", result);
293 
294 	/*--6: raise the rts */
295 	dbg("%s:raising rts",__FUNCTION__);
296 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
297 				 IPW_SIO_SET_PIN,
298 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
299 				 IPW_PIN_SETRTS,
300 				 0,
301 				 NULL,
302 				 0,
303 				 200000);
304 	if (result < 0)
305 		dev_err(&port->dev, "setting dtr failed (error = %d)", result);
306 
307 	kfree(buf_flow_init);
308 	return 0;
309 }
310 
311 static void ipw_close(struct usb_serial_port *port, struct file * filp)
312 {
313 	struct usb_device *dev = port->serial->dev;
314 	int result;
315 
316 	if (tty_hung_up_p(filp)) {
317 		dbg("%s: tty_hung_up_p ...", __FUNCTION__);
318 		return;
319 	}
320 
321 	/*--1: drop the dtr */
322 	dbg("%s:dropping dtr",__FUNCTION__);
323 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
324 				 IPW_SIO_SET_PIN,
325 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
326 				 IPW_PIN_CLRDTR,
327 				 0,
328 				 NULL,
329 				 0,
330 				 200000);
331 	if (result < 0)
332 		dev_err(&port->dev, "dropping dtr failed (error = %d)", result);
333 
334 	/*--2: drop the rts */
335 	dbg("%s:dropping rts",__FUNCTION__);
336 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
337 				 IPW_SIO_SET_PIN, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
338 				 IPW_PIN_CLRRTS,
339 				 0,
340 				 NULL,
341 				 0,
342 				 200000);
343 	if (result < 0)
344 		dev_err(&port->dev, "dropping rts failed (error = %d)", result);
345 
346 
347 	/*--3: purge */
348 	dbg("%s:sending purge",__FUNCTION__);
349 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
350 				 IPW_SIO_PURGE, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
351 				 0x03,
352 				 0,
353 				 NULL,
354 				 0,
355 				 200000);
356 	if (result < 0)
357 		dev_err(&port->dev, "purge failed (error = %d)", result);
358 
359 
360 	/* send RXBULK_off (tell modem to stop transmitting bulk data on rx chan) */
361 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
362 				 IPW_SIO_RXCTL,
363 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
364 				 IPW_RXBULK_OFF,
365 				 0, /* index */
366 				 NULL,
367 				 0,
368 				 100000);
369 
370 	if (result < 0)
371 		dev_err(&port->dev, "Disabling bulk RxRead failed (error = %d)", 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, struct pt_regs *regs)
379 {
380 	struct usb_serial_port *port = urb->context;
381 
382 	dbg("%s", __FUNCTION__);
383 
384 	if (urb->status)
385 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
386 
387 	schedule_work(&port->work);
388 }
389 
390 static int ipw_write(struct usb_serial_port *port, const unsigned char *buf, int count)
391 {
392 	struct usb_device *dev = port->serial->dev;
393 	int ret;
394 
395 	dbg("%s: TOP: count=%d, in_interrupt=%ld", __FUNCTION__,
396 		count, in_interrupt() );
397 
398 	if (count == 0) {
399 		dbg("%s - write request of 0 bytes", __FUNCTION__);
400 		return 0;
401 	}
402 
403 	/* Racy and broken, FIXME properly! */
404 	if (port->write_urb->status == -EINPROGRESS)
405 		return 0;
406 
407 	count = min(count, port->bulk_out_size);
408 	memcpy(port->bulk_out_buffer, buf, count);
409 
410 	dbg("%s count now:%d", __FUNCTION__, count);
411 
412 	usb_fill_bulk_urb(port->write_urb, dev,
413 			  usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
414 			  port->write_urb->transfer_buffer,
415 			  count,
416 			  ipw_write_bulk_callback,
417 			  port);
418 
419 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
420 	if (ret != 0) {
421 		dbg("%s - usb_submit_urb(write bulk) failed with error = %d", __FUNCTION__, ret);
422 		return ret;
423 	}
424 
425 	dbg("%s returning %d", __FUNCTION__, count);
426 	return count;
427 }
428 
429 static int ipw_probe(struct usb_serial_port *port)
430 {
431 	return 0;
432 }
433 
434 static int ipw_disconnect(struct usb_serial_port *port)
435 {
436 	usb_set_serial_port_data(port, NULL);
437 	return 0;
438 }
439 
440 static struct usb_serial_device_type ipw_device = {
441 	.owner =		THIS_MODULE,
442 	.name =			"IPWireless converter",
443 	.short_name =		"ipw",
444 	.id_table =		usb_ipw_ids,
445 	.num_interrupt_in =	NUM_DONT_CARE,
446 	.num_bulk_in =		1,
447 	.num_bulk_out =		1,
448 	.num_ports =		1,
449 	.open =			ipw_open,
450 	.close =		ipw_close,
451 	.port_probe = 		ipw_probe,
452 	.port_remove =		ipw_disconnect,
453 	.write =		ipw_write,
454 	.write_bulk_callback =	ipw_write_bulk_callback,
455 	.read_bulk_callback =	ipw_read_bulk_callback,
456 };
457 
458 
459 
460 static int usb_ipw_init(void)
461 {
462 	int retval;
463 
464 	retval = usb_serial_register(&ipw_device);
465 	if (retval)
466 		return retval;
467 	retval = usb_register(&usb_ipw_driver);
468 	if (retval) {
469 		usb_serial_deregister(&ipw_device);
470 		return retval;
471 	}
472 	info(DRIVER_DESC " " DRIVER_VERSION);
473 	return 0;
474 }
475 
476 static void usb_ipw_exit(void)
477 {
478 	usb_deregister(&usb_ipw_driver);
479 	usb_serial_deregister(&ipw_device);
480 }
481 
482 module_init(usb_ipw_init);
483 module_exit(usb_ipw_exit);
484 
485 /* Module information */
486 MODULE_AUTHOR( DRIVER_AUTHOR );
487 MODULE_DESCRIPTION( DRIVER_DESC );
488 MODULE_LICENSE("GPL");
489 
490 module_param(debug, bool, S_IRUGO | S_IWUSR);
491 MODULE_PARM_DESC(debug, "Debug enabled or not");
492