xref: /openbmc/linux/drivers/usb/serial/ipw.c (revision 87c2ce3b)
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 <asm/uaccess.h>
50 #include "usb-serial.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, 0, 0, 0, 0, 0, 0, 0, 0 }
124 
125 /* Interpretation of modem status lines */
126 /* These need sorting out by individually connecting pins and checking
127  * results. FIXME!
128  * When data is being sent we see 0x30 in the lower byte; this must
129  * contain DSR and CTS ...
130  */
131 #define IPW_DSR			((1<<4) | (1<<5))
132 #define IPW_CTS			((1<<5) | (1<<4))
133 
134 #define IPW_WANTS_TO_SEND	0x30
135 //#define IPW_DTR			/* Data Terminal Ready */
136 //#define IPW_CTS			/* Clear To Send */
137 //#define IPW_CD			/* Carrier Detect */
138 //#define IPW_DSR			/* Data Set Ready */
139 //#define IPW_RxD			/* Receive pin */
140 
141 //#define IPW_LE
142 //#define IPW_RTS
143 //#define IPW_ST
144 //#define IPW_SR
145 //#define IPW_RI			/* Ring Indicator */
146 
147 static struct usb_device_id usb_ipw_ids[] = {
148 	{ USB_DEVICE(IPW_VID, IPW_PID) },
149 	{ },
150 };
151 
152 MODULE_DEVICE_TABLE(usb, usb_ipw_ids);
153 
154 static struct usb_driver usb_ipw_driver = {
155 	.name =		"ipwtty",
156 	.probe =	usb_serial_probe,
157 	.disconnect =	usb_serial_disconnect,
158 	.id_table =	usb_ipw_ids,
159 	.no_dynamic_id = 	1,
160 };
161 
162 static int debug;
163 
164 static void ipw_read_bulk_callback(struct urb *urb, struct pt_regs *regs)
165 {
166 	struct usb_serial_port *port = urb->context;
167 	unsigned char *data = urb->transfer_buffer;
168 	struct tty_struct *tty;
169 	int i;
170 	int result;
171 
172 	dbg("%s - port %d", __FUNCTION__, port->number);
173 
174 	if (urb->status) {
175 		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
176 		return;
177 	}
178 
179 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
180 
181 	tty = port->tty;
182 	if (tty && urb->actual_length) {
183 		for (i = 0; i < urb->actual_length ; ++i) {
184 			/* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
185 			if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
186 				tty_flip_buffer_push(tty);
187 			}
188 			/* this doesn't actually push the data through unless tty->low_latency is set */
189 			tty_insert_flip_char(tty, data[i], 0);
190 		}
191 		tty_flip_buffer_push(tty);
192 	}
193 
194 	/* Continue trying to always read  */
195 	usb_fill_bulk_urb (port->read_urb, port->serial->dev,
196 			   usb_rcvbulkpipe(port->serial->dev,
197 					   port->bulk_in_endpointAddress),
198 			   port->read_urb->transfer_buffer,
199 			   port->read_urb->transfer_buffer_length,
200 			   ipw_read_bulk_callback, port);
201 	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
202 	if (result)
203 		dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
204 	return;
205 }
206 
207 static int ipw_open(struct usb_serial_port *port, struct file *filp)
208 {
209 	struct usb_device *dev = port->serial->dev;
210 	u8 buf_flow_static[16] = IPW_BYTES_FLOWINIT;
211 	u8 *buf_flow_init;
212 	int result;
213 
214 	dbg("%s", __FUNCTION__);
215 
216 	buf_flow_init = kmalloc(16, GFP_KERNEL);
217 	if (!buf_flow_init)
218 		return -ENOMEM;
219 	memcpy(buf_flow_init, buf_flow_static, 16);
220 
221 	if (port->tty)
222 		port->tty->low_latency = 1;
223 
224 	/* --1: Tell the modem to initialize (we think) From sniffs this is always the
225 	 * first thing that gets sent to the modem during opening of the device */
226 	dbg("%s: Sending SIO_INIT (we guess)",__FUNCTION__);
227 	result = usb_control_msg(dev, usb_sndctrlpipe(dev,0),
228 				 IPW_SIO_INIT,
229 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
230 				 0,
231 				 0, /* index */
232 				 NULL,
233 				 0,
234 				 100000);
235 	if (result < 0)
236 		dev_err(&port->dev, "Init of modem failed (error = %d)", result);
237 
238 	/* reset the bulk pipes */
239 	usb_clear_halt(dev, usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress));
240 	usb_clear_halt(dev, usb_sndbulkpipe(dev, port->bulk_out_endpointAddress));
241 
242 	/*--2: Start reading from the device */
243 	dbg("%s: setting up bulk read callback",__FUNCTION__);
244 	usb_fill_bulk_urb(port->read_urb, dev,
245 			  usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
246 			  port->bulk_in_buffer,
247 			  port->bulk_in_size,
248 			  ipw_read_bulk_callback, port);
249 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
250 	if (result < 0)
251 		dbg("%s - usb_submit_urb(read bulk) failed with status %d", __FUNCTION__, result);
252 
253 	/*--3: Tell the modem to open the floodgates on the rx bulk channel */
254 	dbg("%s:asking modem for RxRead (RXBULK_ON)",__FUNCTION__);
255 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
256 				 IPW_SIO_RXCTL,
257 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
258 				 IPW_RXBULK_ON,
259 				 0, /* index */
260 				 NULL,
261 				 0,
262 				 100000);
263 	if (result < 0)
264 		dev_err(&port->dev, "Enabling bulk RxRead failed (error = %d)", result);
265 
266 	/*--4: setup the initial flowcontrol */
267 	dbg("%s:setting init flowcontrol (%s)",__FUNCTION__,buf_flow_init);
268 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
269 				 IPW_SIO_HANDFLOW,
270 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
271 				 0,
272 				 0,
273 				 buf_flow_init,
274 				 0x10,
275 				 200000);
276 	if (result < 0)
277 		dev_err(&port->dev, "initial flowcontrol failed (error = %d)", result);
278 
279 
280 	/*--5: raise the dtr */
281 	dbg("%s:raising dtr",__FUNCTION__);
282 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
283 				 IPW_SIO_SET_PIN,
284 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
285 				 IPW_PIN_SETDTR,
286 				 0,
287 				 NULL,
288 				 0,
289 				 200000);
290 	if (result < 0)
291 		dev_err(&port->dev, "setting dtr failed (error = %d)", result);
292 
293 	/*--6: raise the rts */
294 	dbg("%s:raising rts",__FUNCTION__);
295 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
296 				 IPW_SIO_SET_PIN,
297 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
298 				 IPW_PIN_SETRTS,
299 				 0,
300 				 NULL,
301 				 0,
302 				 200000);
303 	if (result < 0)
304 		dev_err(&port->dev, "setting dtr failed (error = %d)", result);
305 
306 	kfree(buf_flow_init);
307 	return 0;
308 }
309 
310 static void ipw_close(struct usb_serial_port *port, struct file * filp)
311 {
312 	struct usb_device *dev = port->serial->dev;
313 	int result;
314 
315 	if (tty_hung_up_p(filp)) {
316 		dbg("%s: tty_hung_up_p ...", __FUNCTION__);
317 		return;
318 	}
319 
320 	/*--1: drop the dtr */
321 	dbg("%s:dropping dtr",__FUNCTION__);
322 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
323 				 IPW_SIO_SET_PIN,
324 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
325 				 IPW_PIN_CLRDTR,
326 				 0,
327 				 NULL,
328 				 0,
329 				 200000);
330 	if (result < 0)
331 		dev_err(&port->dev, "dropping dtr failed (error = %d)", result);
332 
333 	/*--2: drop the rts */
334 	dbg("%s:dropping rts",__FUNCTION__);
335 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
336 				 IPW_SIO_SET_PIN, USB_TYPE_VENDOR | 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, "dropping rts failed (error = %d)", result);
344 
345 
346 	/*--3: purge */
347 	dbg("%s:sending purge",__FUNCTION__);
348 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
349 				 IPW_SIO_PURGE, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
350 				 0x03,
351 				 0,
352 				 NULL,
353 				 0,
354 				 200000);
355 	if (result < 0)
356 		dev_err(&port->dev, "purge failed (error = %d)", result);
357 
358 
359 	/* send RXBULK_off (tell modem to stop transmitting bulk data on 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, "Disabling bulk RxRead failed (error = %d)", result);
371 
372 	/* shutdown any in-flight urbs that we know about */
373 	usb_kill_urb(port->read_urb);
374 	usb_kill_urb(port->write_urb);
375 }
376 
377 static void ipw_write_bulk_callback(struct urb *urb, struct pt_regs *regs)
378 {
379 	struct usb_serial_port *port = urb->context;
380 
381 	dbg("%s", __FUNCTION__);
382 
383 	if (urb->status)
384 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
385 
386 	schedule_work(&port->work);
387 }
388 
389 static int ipw_write(struct usb_serial_port *port, const unsigned char *buf, int count)
390 {
391 	struct usb_device *dev = port->serial->dev;
392 	int ret;
393 
394 	dbg("%s: TOP: count=%d, in_interrupt=%ld", __FUNCTION__,
395 		count, in_interrupt() );
396 
397 	if (count == 0) {
398 		dbg("%s - write request of 0 bytes", __FUNCTION__);
399 		return 0;
400 	}
401 
402 	spin_lock(&port->lock);
403 	if (port->write_urb_busy) {
404 		spin_unlock(&port->lock);
405 		dbg("%s - already writing", __FUNCTION__);
406 		return 0;
407 	}
408 	port->write_urb_busy = 1;
409 	spin_unlock(&port->lock);
410 
411 	count = min(count, port->bulk_out_size);
412 	memcpy(port->bulk_out_buffer, buf, count);
413 
414 	dbg("%s count now:%d", __FUNCTION__, count);
415 
416 	usb_fill_bulk_urb(port->write_urb, dev,
417 			  usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
418 			  port->write_urb->transfer_buffer,
419 			  count,
420 			  ipw_write_bulk_callback,
421 			  port);
422 
423 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
424 	if (ret != 0) {
425 		port->write_urb_busy = 0;
426 		dbg("%s - usb_submit_urb(write bulk) failed with error = %d", __FUNCTION__, ret);
427 		return ret;
428 	}
429 
430 	dbg("%s returning %d", __FUNCTION__, count);
431 	return count;
432 }
433 
434 static int ipw_probe(struct usb_serial_port *port)
435 {
436 	return 0;
437 }
438 
439 static int ipw_disconnect(struct usb_serial_port *port)
440 {
441 	usb_set_serial_port_data(port, NULL);
442 	return 0;
443 }
444 
445 static struct usb_serial_driver ipw_device = {
446 	.driver = {
447 		.owner =	THIS_MODULE,
448 		.name =		"ipw",
449 	},
450 	.description =		"IPWireless converter",
451 	.id_table =		usb_ipw_ids,
452 	.num_interrupt_in =	NUM_DONT_CARE,
453 	.num_bulk_in =		1,
454 	.num_bulk_out =		1,
455 	.num_ports =		1,
456 	.open =			ipw_open,
457 	.close =		ipw_close,
458 	.port_probe = 		ipw_probe,
459 	.port_remove =		ipw_disconnect,
460 	.write =		ipw_write,
461 	.write_bulk_callback =	ipw_write_bulk_callback,
462 	.read_bulk_callback =	ipw_read_bulk_callback,
463 };
464 
465 
466 
467 static int usb_ipw_init(void)
468 {
469 	int retval;
470 
471 	retval = usb_serial_register(&ipw_device);
472 	if (retval)
473 		return retval;
474 	retval = usb_register(&usb_ipw_driver);
475 	if (retval) {
476 		usb_serial_deregister(&ipw_device);
477 		return retval;
478 	}
479 	info(DRIVER_DESC " " DRIVER_VERSION);
480 	return 0;
481 }
482 
483 static void usb_ipw_exit(void)
484 {
485 	usb_deregister(&usb_ipw_driver);
486 	usb_serial_deregister(&ipw_device);
487 }
488 
489 module_init(usb_ipw_init);
490 module_exit(usb_ipw_exit);
491 
492 /* Module information */
493 MODULE_AUTHOR( DRIVER_AUTHOR );
494 MODULE_DESCRIPTION( DRIVER_DESC );
495 MODULE_LICENSE("GPL");
496 
497 module_param(debug, bool, S_IRUGO | S_IWUSR);
498 MODULE_PARM_DESC(debug, "Debug enabled or not");
499