1/*****************************************************************************
2*
3* Filename:      mcs7780.c
4* Version:       0.4-alpha
5* Description:   Irda MosChip USB Dongle Driver
6* Authors:       Lukasz Stelmach <stlman@poczta.fm>
7* 		 Brian Pugh <bpugh@cs.pdx.edu>
8*		 Judy Fischbach <jfisch@cs.pdx.edu>
9*
10*       Based on stir4200 driver, but some things done differently.
11*       Based on earlier driver by Paul Stewart <stewart@parc.com>
12*
13*       Copyright (C) 2000, Roman Weissgaerber <weissg@vienna.at>
14*       Copyright (C) 2001, Dag Brattli <dag@brattli.net>
15*       Copyright (C) 2001, Jean Tourrilhes <jt@hpl.hp.com>
16*       Copyright (C) 2004, Stephen Hemminger <shemminger@osdl.org>
17*       Copyright (C) 2005, Lukasz Stelmach <stlman@poczta.fm>
18*       Copyright (C) 2005, Brian Pugh <bpugh@cs.pdx.edu>
19*       Copyright (C) 2005, Judy Fischbach <jfisch@cs.pdx.edu>
20*
21*       This program is free software; you can redistribute it and/or modify
22*       it under the terms of the GNU General Public License as published by
23*       the Free Software Foundation; either version 2 of the License, or
24*       (at your option) any later version.
25*
26*       This program is distributed in the hope that it will be useful,
27*       but WITHOUT ANY WARRANTY; without even the implied warranty of
28*       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
29*       GNU General Public License for more details.
30*
31*       You should have received a copy of the GNU General Public License
32*       along with this program; if not, write to the Free Software
33*       Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
34*
35*****************************************************************************/
36
37/*
38 * MCS7780 is a simple USB to IrDA bridge by MosChip. It is neither
39 * compatibile with irda-usb nor with stir4200. Although it is quite
40 * similar to the later as far as general idea of operation is concerned.
41 * That is it requires the software to do all the framing job at SIR speeds.
42 * The hardware does take care of the framing at MIR and FIR speeds.
43 * It supports all speeds from 2400 through 4Mbps
44 */
45
46#include <linux/module.h>
47#include <linux/moduleparam.h>
48#include <linux/kernel.h>
49#include <linux/types.h>
50#include <linux/errno.h>
51#include <linux/slab.h>
52#include <linux/usb.h>
53#include <linux/device.h>
54#include <linux/crc32.h>
55
56#include <asm/unaligned.h>
57#include <asm/byteorder.h>
58#include <asm/uaccess.h>
59
60#include <net/irda/irda.h>
61#include <net/irda/wrapper.h>
62#include <net/irda/crc.h>
63
64#include "mcs7780.h"
65
66#define MCS_VENDOR_ID 0x9710
67#define MCS_PRODUCT_ID 0x7780
68
69static struct usb_device_id mcs_table[] = {
70	/* MosChip Corp.,  MCS7780 FIR-USB Adapter */
71	{USB_DEVICE(MCS_VENDOR_ID, MCS_PRODUCT_ID)},
72	{},
73};
74
75MODULE_AUTHOR("Brian Pugh <bpugh@cs.pdx.edu>");
76MODULE_DESCRIPTION("IrDA-USB Dongle Driver for MosChip MCS7780");
77MODULE_VERSION("0.3alpha");
78MODULE_LICENSE("GPL");
79
80MODULE_DEVICE_TABLE(usb, mcs_table);
81
82static int qos_mtt_bits = 0x07 /* > 1ms */ ;
83module_param(qos_mtt_bits, int, 0);
84MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
85
86static int receive_mode = 0x1;
87module_param(receive_mode, int, 0);
88MODULE_PARM_DESC(receive_mode,
89		 "Receive mode of the device (1:fast, 0:slow, default:1)");
90
91static int sir_tweak = 1;
92module_param(sir_tweak, int, 0444);
93MODULE_PARM_DESC(sir_tweak,
94		 "Default pulse width (1:1.6us, 0:3/16 bit, default:1).");
95
96static int transceiver_type = MCS_TSC_VISHAY;
97module_param(transceiver_type, int, 0444);
98MODULE_PARM_DESC(transceiver_type, "IR transceiver type, see mcs7780.h.");
99
100static struct usb_driver mcs_driver = {
101	.name = "mcs7780",
102	.probe = mcs_probe,
103	.disconnect = mcs_disconnect,
104	.id_table = mcs_table,
105};
106
107/* speed flag selection by direct addressing.
108addr = (speed >> 8) & 0x0f
109
1100x1   57600	 0x2  115200	 0x4 1152000	 0x5    9600
1110x6   38400	 0x9    2400	 0xa  576000	 0xb   19200
112
1134Mbps (or 2400) must be checked separately. Since it also has
114to be programmed in a different manner that is not a big problem.
115*/
116static __u16 mcs_speed_set[16] = { 0,
117	MCS_SPEED_57600,
118	MCS_SPEED_115200,
119	0,
120	MCS_SPEED_1152000,
121	MCS_SPEED_9600,
122	MCS_SPEED_38400,
123	0, 0,
124	MCS_SPEED_2400,
125	MCS_SPEED_576000,
126	MCS_SPEED_19200,
127	0, 0, 0,
128};
129
130/* Set given 16 bit register with a 16 bit value. Send control message
131 * to set dongle register. */
132static int mcs_set_reg(struct mcs_cb *mcs, __u16 reg, __u16 val)
133{
134	struct usb_device *dev = mcs->usbdev;
135	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
136			       MCS_WR_RTYPE, val, reg, NULL, 0,
137			       msecs_to_jiffies(MCS_CTRL_TIMEOUT));
138}
139
140/* Get 16 bit register value. Send contol message to read dongle register. */
141static int mcs_get_reg(struct mcs_cb *mcs, __u16 reg, __u16 * val)
142{
143	struct usb_device *dev = mcs->usbdev;
144	int ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
145				  MCS_RD_RTYPE, 0, reg, val, 2,
146				  msecs_to_jiffies(MCS_CTRL_TIMEOUT));
147
148	return ret;
149}
150
151/* Setup a communication between mcs7780 and TFDU chips.  It is described
152 * in more detail in the data sheet.  The setup sequence puts the the
153 * vishay tranceiver into high speed mode.  It will also receive SIR speed
154 * packets but at reduced sensitivity.
155 */
156
157/* 0: OK 1:ERROR */
158static inline int mcs_setup_transceiver_vishay(struct mcs_cb *mcs)
159{
160	int ret = 0;
161	__u16 rval;
162
163	/* mcs_get_reg should read exactly two bytes from the dongle */
164	ret = mcs_get_reg(mcs, MCS_XCVR_REG, &rval);
165	if (unlikely(ret != 2)) {
166		ret = -EIO;
167		goto error;
168	}
169
170	/* The MCS_XCVR_CONF bit puts the transceiver into configuration
171	 * mode.  The MCS_MODE0 bit must start out high (1) and then
172	 * transition to low and the MCS_STFIR and MCS_MODE1 bits must
173	 * be low.
174	 */
175	rval |= (MCS_MODE0 | MCS_XCVR_CONF);
176	rval &= ~MCS_STFIR;
177	rval &= ~MCS_MODE1;
178	ret = mcs_set_reg(mcs, MCS_XCVR_REG, rval);
179	if (unlikely(ret))
180		goto error;
181
182	rval &= ~MCS_MODE0;
183	ret = mcs_set_reg(mcs, MCS_XCVR_REG, rval);
184	if (unlikely(ret))
185		goto error;
186
187	rval &= ~MCS_XCVR_CONF;
188	ret = mcs_set_reg(mcs, MCS_XCVR_REG, rval);
189	if (unlikely(ret))
190		goto error;
191
192	ret = 0;
193error:
194	return ret;
195}
196
197/* Setup a communication between mcs7780 and agilent chip. */
198static inline int mcs_setup_transceiver_agilent(struct mcs_cb *mcs)
199{
200	net_warn_ratelimited("This transceiver type is not supported yet\n");
201	return 1;
202}
203
204/* Setup a communication between mcs7780 and sharp chip. */
205static inline int mcs_setup_transceiver_sharp(struct mcs_cb *mcs)
206{
207	net_warn_ratelimited("This transceiver type is not supported yet\n");
208	return 1;
209}
210
211/* Common setup for all transceivers */
212static inline int mcs_setup_transceiver(struct mcs_cb *mcs)
213{
214	int ret = 0;
215	__u16 rval;
216	const char *msg;
217
218	msg = "Basic transceiver setup error";
219
220	/* read value of MODE Register, set the DRIVER and RESET bits
221	* and write value back out to MODE Register
222	*/
223	ret = mcs_get_reg(mcs, MCS_MODE_REG, &rval);
224	if(unlikely(ret != 2))
225		goto error;
226	rval |= MCS_DRIVER;	/* put the mcs7780 into configuration mode. */
227	ret = mcs_set_reg(mcs, MCS_MODE_REG, rval);
228	if(unlikely(ret))
229		goto error;
230
231	rval = 0;		/* set min pulse width to 0 initially. */
232	ret = mcs_set_reg(mcs, MCS_MINRXPW_REG, rval);
233	if(unlikely(ret))
234		goto error;
235
236	ret = mcs_get_reg(mcs, MCS_MODE_REG, &rval);
237	if(unlikely(ret != 2))
238		goto error;
239
240	rval &= ~MCS_FIR;	/* turn off fir mode. */
241	if(mcs->sir_tweak)
242		rval |= MCS_SIR16US;	/* 1.6us pulse width */
243	else
244		rval &= ~MCS_SIR16US;	/* 3/16 bit time pulse width */
245
246	/* make sure ask mode and back to back packets are off. */
247	rval &= ~(MCS_BBTG | MCS_ASK);
248
249	rval &= ~MCS_SPEED_MASK;
250	rval |= MCS_SPEED_9600;		/* make sure initial speed is 9600. */
251	mcs->speed = 9600;
252	mcs->new_speed = 0;		/* new_speed is set to 0 */
253	rval &= ~MCS_PLLPWDN;		/* disable power down. */
254
255	/* make sure device determines direction and that the auto send sip
256	 * pulse are on.
257	 */
258	rval |= MCS_DTD | MCS_SIPEN;
259
260	ret = mcs_set_reg(mcs, MCS_MODE_REG, rval);
261	if(unlikely(ret))
262		goto error;
263
264	msg = "transceiver model specific setup error";
265	switch (mcs->transceiver_type) {
266	case MCS_TSC_VISHAY:
267		ret = mcs_setup_transceiver_vishay(mcs);
268		break;
269
270	case MCS_TSC_SHARP:
271		ret = mcs_setup_transceiver_sharp(mcs);
272		break;
273
274	case MCS_TSC_AGILENT:
275		ret = mcs_setup_transceiver_agilent(mcs);
276		break;
277
278	default:
279		net_warn_ratelimited("Unknown transceiver type: %d\n",
280				     mcs->transceiver_type);
281		ret = 1;
282	}
283	if (unlikely(ret))
284		goto error;
285
286	/* If transceiver is not SHARP, then if receive mode set
287	* on the RXFAST bit in the XCVR Register otherwise unset it
288	*/
289	if (mcs->transceiver_type != MCS_TSC_SHARP) {
290
291		ret = mcs_get_reg(mcs, MCS_XCVR_REG, &rval);
292		if (unlikely(ret != 2))
293			goto error;
294		if (mcs->receive_mode)
295			rval |= MCS_RXFAST;
296		else
297			rval &= ~MCS_RXFAST;
298		ret = mcs_set_reg(mcs, MCS_XCVR_REG, rval);
299		if (unlikely(ret))
300			goto error;
301	}
302
303	msg = "transceiver reset";
304
305	ret = mcs_get_reg(mcs, MCS_MODE_REG, &rval);
306	if (unlikely(ret != 2))
307		goto error;
308
309	/* reset the mcs7780 so all changes take effect. */
310	rval &= ~MCS_RESET;
311	ret = mcs_set_reg(mcs, MCS_MODE_REG, rval);
312	if (unlikely(ret))
313		goto error;
314	else
315		return ret;
316
317error:
318	net_err_ratelimited("%s\n", msg);
319	return ret;
320}
321
322/* Wraps the data in format for SIR */
323static inline int mcs_wrap_sir_skb(struct sk_buff *skb, __u8 * buf)
324{
325	int wraplen;
326
327	/* 2: full frame length, including "the length" */
328	wraplen = async_wrap_skb(skb, buf + 2, 4094);
329
330	wraplen += 2;
331	buf[0] = wraplen & 0xff;
332	buf[1] = (wraplen >> 8) & 0xff;
333
334	return wraplen;
335}
336
337/* Wraps the data in format for FIR */
338static unsigned mcs_wrap_fir_skb(const struct sk_buff *skb, __u8 *buf)
339{
340	unsigned int len = 0;
341	__u32 fcs = ~(crc32_le(~0, skb->data, skb->len));
342
343	/* add 2 bytes for length value and 4 bytes for fcs. */
344	len = skb->len + 6;
345
346	/* The mcs7780 requires that the first two bytes are the packet
347	 * length in little endian order.  Note: the length value includes
348	 * the two bytes for the length value itself.
349	 */
350	buf[0] = len & 0xff;
351	buf[1] = (len >> 8) & 0xff;
352	/* copy the data into the tx buffer. */
353	skb_copy_from_linear_data(skb, buf + 2, skb->len);
354	/* put the fcs in the last four bytes in little endian order. */
355	buf[len - 4] = fcs & 0xff;
356	buf[len - 3] = (fcs >> 8) & 0xff;
357	buf[len - 2] = (fcs >> 16) & 0xff;
358	buf[len - 1] = (fcs >> 24) & 0xff;
359
360	return len;
361}
362
363/* Wraps the data in format for MIR */
364static unsigned mcs_wrap_mir_skb(const struct sk_buff *skb, __u8 *buf)
365{
366	__u16 fcs = 0;
367	int len = skb->len + 4;
368
369	fcs = ~(irda_calc_crc16(~fcs, skb->data, skb->len));
370	/* put the total packet length in first.  Note: packet length
371	 * value includes the two bytes that hold the packet length
372	 * itself.
373	 */
374	buf[0] = len & 0xff;
375	buf[1] = (len >> 8) & 0xff;
376	/* copy the data */
377	skb_copy_from_linear_data(skb, buf + 2, skb->len);
378	/* put the fcs in last two bytes in little endian order. */
379	buf[len - 2] = fcs & 0xff;
380	buf[len - 1] = (fcs >> 8) & 0xff;
381
382	return len;
383}
384
385/* Unwrap received packets at MIR speed.  A 16 bit crc_ccitt checksum is
386 * used for the fcs.  When performed over the entire packet the result
387 * should be GOOD_FCS = 0xf0b8.  Hands the unwrapped data off to the IrDA
388 * layer via a sk_buff.
389 */
390static void mcs_unwrap_mir(struct mcs_cb *mcs, __u8 *buf, int len)
391{
392	__u16 fcs;
393	int new_len;
394	struct sk_buff *skb;
395
396	/* Assume that the frames are going to fill a single packet
397	 * rather than span multiple packets.
398	 */
399
400	new_len = len - 2;
401	if(unlikely(new_len <= 0)) {
402		net_err_ratelimited("%s short frame length %d\n",
403				    mcs->netdev->name, new_len);
404		++mcs->netdev->stats.rx_errors;
405		++mcs->netdev->stats.rx_length_errors;
406		return;
407	}
408	fcs = 0;
409	fcs = irda_calc_crc16(~fcs, buf, len);
410
411	if(fcs != GOOD_FCS) {
412		net_err_ratelimited("crc error calc 0x%x len %d\n",
413				    fcs, new_len);
414		mcs->netdev->stats.rx_errors++;
415		mcs->netdev->stats.rx_crc_errors++;
416		return;
417	}
418
419	skb = dev_alloc_skb(new_len + 1);
420	if(unlikely(!skb)) {
421		++mcs->netdev->stats.rx_dropped;
422		return;
423	}
424
425	skb_reserve(skb, 1);
426	skb_copy_to_linear_data(skb, buf, new_len);
427	skb_put(skb, new_len);
428	skb_reset_mac_header(skb);
429	skb->protocol = htons(ETH_P_IRDA);
430	skb->dev = mcs->netdev;
431
432	netif_rx(skb);
433
434	mcs->netdev->stats.rx_packets++;
435	mcs->netdev->stats.rx_bytes += new_len;
436}
437
438/* Unwrap received packets at FIR speed.  A 32 bit crc_ccitt checksum is
439 * used for the fcs.  Hands the unwrapped data off to the IrDA
440 * layer via a sk_buff.
441 */
442static void mcs_unwrap_fir(struct mcs_cb *mcs, __u8 *buf, int len)
443{
444	__u32 fcs;
445	int new_len;
446	struct sk_buff *skb;
447
448	/* Assume that the frames are going to fill a single packet
449	 * rather than span multiple packets.  This is most likely a false
450	 * assumption.
451	 */
452
453	new_len = len - 4;
454	if(unlikely(new_len <= 0)) {
455		net_err_ratelimited("%s short frame length %d\n",
456				    mcs->netdev->name, new_len);
457		++mcs->netdev->stats.rx_errors;
458		++mcs->netdev->stats.rx_length_errors;
459		return;
460	}
461
462	fcs = ~(crc32_le(~0, buf, new_len));
463	if(fcs != get_unaligned_le32(buf + new_len)) {
464		net_err_ratelimited("crc error calc 0x%x len %d\n",
465				    fcs, new_len);
466		mcs->netdev->stats.rx_errors++;
467		mcs->netdev->stats.rx_crc_errors++;
468		return;
469	}
470
471	skb = dev_alloc_skb(new_len + 1);
472	if(unlikely(!skb)) {
473		++mcs->netdev->stats.rx_dropped;
474		return;
475	}
476
477	skb_reserve(skb, 1);
478	skb_copy_to_linear_data(skb, buf, new_len);
479	skb_put(skb, new_len);
480	skb_reset_mac_header(skb);
481	skb->protocol = htons(ETH_P_IRDA);
482	skb->dev = mcs->netdev;
483
484	netif_rx(skb);
485
486	mcs->netdev->stats.rx_packets++;
487	mcs->netdev->stats.rx_bytes += new_len;
488}
489
490
491/* Allocates urbs for both receive and transmit.
492 * If alloc fails return error code 0 (fail) otherwise
493 * return error code 1 (success).
494 */
495static inline int mcs_setup_urbs(struct mcs_cb *mcs)
496{
497	mcs->rx_urb = NULL;
498
499	mcs->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
500	if (!mcs->tx_urb)
501		return 0;
502
503	mcs->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
504	if (!mcs->rx_urb) {
505		usb_free_urb(mcs->tx_urb);
506		mcs->tx_urb = NULL;
507		return 0;
508	}
509
510	return 1;
511}
512
513/* Sets up state to be initially outside frame, gets receive urb,
514 * sets status to successful and then submits the urb to start
515 * receiving the data.
516 */
517static inline int mcs_receive_start(struct mcs_cb *mcs)
518{
519	mcs->rx_buff.in_frame = FALSE;
520	mcs->rx_buff.state = OUTSIDE_FRAME;
521
522	usb_fill_bulk_urb(mcs->rx_urb, mcs->usbdev,
523			  usb_rcvbulkpipe(mcs->usbdev, mcs->ep_in),
524			  mcs->in_buf, 4096, mcs_receive_irq, mcs);
525
526	mcs->rx_urb->status = 0;
527	return usb_submit_urb(mcs->rx_urb, GFP_KERNEL);
528}
529
530/* Finds the in and out endpoints for the mcs control block */
531static inline int mcs_find_endpoints(struct mcs_cb *mcs,
532				     struct usb_host_endpoint *ep, int epnum)
533{
534	int i;
535	int ret = 0;
536
537	/* If no place to store the endpoints just return */
538	if (!ep)
539		return ret;
540
541	/* cycle through all endpoints, find the first two that are DIR_IN */
542	for (i = 0; i < epnum; i++) {
543		if (ep[i].desc.bEndpointAddress & USB_DIR_IN)
544			mcs->ep_in = ep[i].desc.bEndpointAddress;
545		else
546			mcs->ep_out = ep[i].desc.bEndpointAddress;
547
548		/* MosChip says that the chip has only two bulk
549		 * endpoints. Find one for each direction and move on.
550		 */
551		if ((mcs->ep_in != 0) && (mcs->ep_out != 0)) {
552			ret = 1;
553			break;
554		}
555	}
556
557	return ret;
558}
559
560static void mcs_speed_work(struct work_struct *work)
561{
562	struct mcs_cb *mcs = container_of(work, struct mcs_cb, work);
563	struct net_device *netdev = mcs->netdev;
564
565	mcs_speed_change(mcs);
566	netif_wake_queue(netdev);
567}
568
569/* Function to change the speed of the mcs7780.  Fully supports SIR,
570 * MIR, and FIR speeds.
571 */
572static int mcs_speed_change(struct mcs_cb *mcs)
573{
574	int ret = 0;
575	int rst = 0;
576	int cnt = 0;
577	__u16 nspeed;
578	__u16 rval;
579
580	nspeed = mcs_speed_set[(mcs->new_speed >> 8) & 0x0f];
581
582	do {
583		mcs_get_reg(mcs, MCS_RESV_REG, &rval);
584	} while(cnt++ < 100 && (rval & MCS_IRINTX));
585
586	if (cnt > 100) {
587		net_err_ratelimited("unable to change speed\n");
588		ret = -EIO;
589		goto error;
590	}
591
592	mcs_get_reg(mcs, MCS_MODE_REG, &rval);
593
594	/* MINRXPW values recommended by MosChip */
595	if (mcs->new_speed <= 115200) {
596		rval &= ~MCS_FIR;
597
598		if ((rst = (mcs->speed > 115200)))
599			mcs_set_reg(mcs, MCS_MINRXPW_REG, 0);
600
601	} else if (mcs->new_speed <= 1152000) {
602		rval &= ~MCS_FIR;
603
604		if ((rst = !(mcs->speed == 576000 || mcs->speed == 1152000)))
605			mcs_set_reg(mcs, MCS_MINRXPW_REG, 5);
606
607	} else {
608		rval |= MCS_FIR;
609
610		if ((rst = (mcs->speed != 4000000)))
611			mcs_set_reg(mcs, MCS_MINRXPW_REG, 5);
612
613	}
614
615	rval &= ~MCS_SPEED_MASK;
616	rval |= nspeed;
617
618	ret = mcs_set_reg(mcs, MCS_MODE_REG, rval);
619	if (unlikely(ret))
620		goto error;
621
622	if (rst)
623		switch (mcs->transceiver_type) {
624		case MCS_TSC_VISHAY:
625			ret = mcs_setup_transceiver_vishay(mcs);
626			break;
627
628		case MCS_TSC_SHARP:
629			ret = mcs_setup_transceiver_sharp(mcs);
630			break;
631
632		case MCS_TSC_AGILENT:
633			ret = mcs_setup_transceiver_agilent(mcs);
634			break;
635
636		default:
637			ret = 1;
638			net_warn_ratelimited("Unknown transceiver type: %d\n",
639					     mcs->transceiver_type);
640		}
641	if (unlikely(ret))
642		goto error;
643
644	mcs_get_reg(mcs, MCS_MODE_REG, &rval);
645	rval &= ~MCS_RESET;
646	ret = mcs_set_reg(mcs, MCS_MODE_REG, rval);
647
648	mcs->speed = mcs->new_speed;
649error:
650	mcs->new_speed = 0;
651	return ret;
652}
653
654/* Ioctl calls not supported at this time.  Can be an area of future work. */
655static int mcs_net_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
656{
657	/* struct if_irda_req *irq = (struct if_irda_req *)rq; */
658	/* struct mcs_cb *mcs = netdev_priv(netdev); */
659	int ret = 0;
660
661	switch (cmd) {
662	default:
663		ret = -EOPNOTSUPP;
664	}
665
666	return ret;
667}
668
669/* Network device is taken down, done by "ifconfig irda0 down" */
670static int mcs_net_close(struct net_device *netdev)
671{
672	int ret = 0;
673	struct mcs_cb *mcs = netdev_priv(netdev);
674
675	/* Stop transmit processing */
676	netif_stop_queue(netdev);
677
678	kfree_skb(mcs->rx_buff.skb);
679
680	/* kill and free the receive and transmit URBs */
681	usb_kill_urb(mcs->rx_urb);
682	usb_free_urb(mcs->rx_urb);
683	usb_kill_urb(mcs->tx_urb);
684	usb_free_urb(mcs->tx_urb);
685
686	/* Stop and remove instance of IrLAP */
687	if (mcs->irlap)
688		irlap_close(mcs->irlap);
689
690	mcs->irlap = NULL;
691	return ret;
692}
693
694/* Network device is taken up, done by "ifconfig irda0 up" */
695static int mcs_net_open(struct net_device *netdev)
696{
697	struct mcs_cb *mcs = netdev_priv(netdev);
698	char hwname[16];
699	int ret = 0;
700
701	ret = usb_clear_halt(mcs->usbdev,
702			     usb_sndbulkpipe(mcs->usbdev, mcs->ep_in));
703	if (ret)
704		goto error1;
705	ret = usb_clear_halt(mcs->usbdev,
706			     usb_rcvbulkpipe(mcs->usbdev, mcs->ep_out));
707	if (ret)
708		goto error1;
709
710	ret = mcs_setup_transceiver(mcs);
711	if (ret)
712		goto error1;
713
714	ret = -ENOMEM;
715
716	/* Initialize for SIR/FIR to copy data directly into skb.  */
717	mcs->receiving = 0;
718	mcs->rx_buff.truesize = IRDA_SKB_MAX_MTU;
719	mcs->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
720	if (!mcs->rx_buff.skb)
721		goto error1;
722
723	skb_reserve(mcs->rx_buff.skb, 1);
724	mcs->rx_buff.head = mcs->rx_buff.skb->data;
725
726	/*
727	 * Now that everything should be initialized properly,
728	 * Open new IrLAP layer instance to take care of us...
729	 * Note : will send immediately a speed change...
730	 */
731	sprintf(hwname, "usb#%d", mcs->usbdev->devnum);
732	mcs->irlap = irlap_open(netdev, &mcs->qos, hwname);
733	if (!mcs->irlap) {
734		net_err_ratelimited("mcs7780: irlap_open failed\n");
735		goto error2;
736	}
737
738	if (!mcs_setup_urbs(mcs))
739		goto error3;
740
741	ret = mcs_receive_start(mcs);
742	if (ret)
743		goto error4;
744
745	netif_start_queue(netdev);
746	return 0;
747
748error4:
749	usb_free_urb(mcs->rx_urb);
750	usb_free_urb(mcs->tx_urb);
751error3:
752	irlap_close(mcs->irlap);
753error2:
754	kfree_skb(mcs->rx_buff.skb);
755error1:
756	return ret;
757}
758
759/* Receive callback function.  */
760static void mcs_receive_irq(struct urb *urb)
761{
762	__u8 *bytes;
763	struct mcs_cb *mcs = urb->context;
764	int i;
765	int ret;
766
767	if (!netif_running(mcs->netdev))
768		return;
769
770	if (urb->status)
771		return;
772
773	if (urb->actual_length > 0) {
774		bytes = urb->transfer_buffer;
775
776		/* MCS returns frames without BOF and EOF
777		 * I assume it returns whole frames.
778		 */
779		/* SIR speed */
780		if(mcs->speed < 576000) {
781			async_unwrap_char(mcs->netdev, &mcs->netdev->stats,
782				  &mcs->rx_buff, 0xc0);
783
784			for (i = 0; i < urb->actual_length; i++)
785				async_unwrap_char(mcs->netdev, &mcs->netdev->stats,
786					  &mcs->rx_buff, bytes[i]);
787
788			async_unwrap_char(mcs->netdev, &mcs->netdev->stats,
789				  &mcs->rx_buff, 0xc1);
790		}
791		/* MIR speed */
792		else if(mcs->speed == 576000 || mcs->speed == 1152000) {
793			mcs_unwrap_mir(mcs, urb->transfer_buffer,
794				urb->actual_length);
795		}
796		/* FIR speed */
797		else {
798			mcs_unwrap_fir(mcs, urb->transfer_buffer,
799				urb->actual_length);
800		}
801	}
802
803	ret = usb_submit_urb(urb, GFP_ATOMIC);
804}
805
806/* Transmit callback function.  */
807static void mcs_send_irq(struct urb *urb)
808{
809	struct mcs_cb *mcs = urb->context;
810	struct net_device *ndev = mcs->netdev;
811
812	if (unlikely(mcs->new_speed))
813		schedule_work(&mcs->work);
814	else
815		netif_wake_queue(ndev);
816}
817
818/* Transmit callback function.  */
819static netdev_tx_t mcs_hard_xmit(struct sk_buff *skb,
820				       struct net_device *ndev)
821{
822	unsigned long flags;
823	struct mcs_cb *mcs;
824	int wraplen;
825	int ret = 0;
826
827	netif_stop_queue(ndev);
828	mcs = netdev_priv(ndev);
829
830	spin_lock_irqsave(&mcs->lock, flags);
831
832	mcs->new_speed = irda_get_next_speed(skb);
833	if (likely(mcs->new_speed == mcs->speed))
834		mcs->new_speed = 0;
835
836	/* SIR speed */
837	if(mcs->speed < 576000) {
838		wraplen = mcs_wrap_sir_skb(skb, mcs->out_buf);
839	}
840	/* MIR speed */
841	else if(mcs->speed == 576000 || mcs->speed == 1152000) {
842		wraplen = mcs_wrap_mir_skb(skb, mcs->out_buf);
843	}
844	/* FIR speed */
845	else {
846		wraplen = mcs_wrap_fir_skb(skb, mcs->out_buf);
847	}
848	usb_fill_bulk_urb(mcs->tx_urb, mcs->usbdev,
849			  usb_sndbulkpipe(mcs->usbdev, mcs->ep_out),
850			  mcs->out_buf, wraplen, mcs_send_irq, mcs);
851
852	if ((ret = usb_submit_urb(mcs->tx_urb, GFP_ATOMIC))) {
853		net_err_ratelimited("failed tx_urb: %d\n", ret);
854		switch (ret) {
855		case -ENODEV:
856		case -EPIPE:
857			break;
858		default:
859			mcs->netdev->stats.tx_errors++;
860			netif_start_queue(ndev);
861		}
862	} else {
863		mcs->netdev->stats.tx_packets++;
864		mcs->netdev->stats.tx_bytes += skb->len;
865	}
866
867	dev_kfree_skb(skb);
868	spin_unlock_irqrestore(&mcs->lock, flags);
869	return NETDEV_TX_OK;
870}
871
872static const struct net_device_ops mcs_netdev_ops = {
873	.ndo_open = mcs_net_open,
874	.ndo_stop = mcs_net_close,
875	.ndo_start_xmit = mcs_hard_xmit,
876	.ndo_do_ioctl = mcs_net_ioctl,
877};
878
879/*
880 * This function is called by the USB subsystem for each new device in the
881 * system.  Need to verify the device and if it is, then start handling it.
882 */
883static int mcs_probe(struct usb_interface *intf,
884		     const struct usb_device_id *id)
885{
886	struct usb_device *udev = interface_to_usbdev(intf);
887	struct net_device *ndev = NULL;
888	struct mcs_cb *mcs;
889	int ret = -ENOMEM;
890
891	ndev = alloc_irdadev(sizeof(*mcs));
892	if (!ndev)
893		goto error1;
894
895	pr_debug("MCS7780 USB-IrDA bridge found at %d.\n", udev->devnum);
896
897	SET_NETDEV_DEV(ndev, &intf->dev);
898
899	ret = usb_reset_configuration(udev);
900	if (ret != 0) {
901		net_err_ratelimited("mcs7780: usb reset configuration failed\n");
902		goto error2;
903	}
904
905	mcs = netdev_priv(ndev);
906	mcs->usbdev = udev;
907	mcs->netdev = ndev;
908	spin_lock_init(&mcs->lock);
909
910	/* Initialize QoS for this device */
911	irda_init_max_qos_capabilies(&mcs->qos);
912
913	/* That's the Rx capability. */
914	mcs->qos.baud_rate.bits &=
915	    IR_2400 | IR_9600 | IR_19200 | IR_38400 | IR_57600 | IR_115200
916		| IR_576000 | IR_1152000 | (IR_4000000 << 8);
917
918
919	mcs->qos.min_turn_time.bits &= qos_mtt_bits;
920	irda_qos_bits_to_value(&mcs->qos);
921
922	/* Speed change work initialisation*/
923	INIT_WORK(&mcs->work, mcs_speed_work);
924
925	ndev->netdev_ops = &mcs_netdev_ops;
926
927	if (!intf->cur_altsetting) {
928		ret = -ENOMEM;
929		goto error2;
930	}
931
932	ret = mcs_find_endpoints(mcs, intf->cur_altsetting->endpoint,
933				 intf->cur_altsetting->desc.bNumEndpoints);
934	if (!ret) {
935		ret = -ENODEV;
936		goto error2;
937	}
938
939	ret = register_netdev(ndev);
940	if (ret != 0)
941		goto error2;
942
943	pr_debug("IrDA: Registered MosChip MCS7780 device as %s\n",
944		 ndev->name);
945
946	mcs->transceiver_type = transceiver_type;
947	mcs->sir_tweak = sir_tweak;
948	mcs->receive_mode = receive_mode;
949
950	usb_set_intfdata(intf, mcs);
951	return 0;
952
953error2:
954	free_netdev(ndev);
955
956error1:
957	return ret;
958}
959
960/* The current device is removed, the USB layer tells us to shut down. */
961static void mcs_disconnect(struct usb_interface *intf)
962{
963	struct mcs_cb *mcs = usb_get_intfdata(intf);
964
965	if (!mcs)
966		return;
967
968	cancel_work_sync(&mcs->work);
969
970	unregister_netdev(mcs->netdev);
971	free_netdev(mcs->netdev);
972
973	usb_set_intfdata(intf, NULL);
974	pr_debug("MCS7780 now disconnected.\n");
975}
976
977module_usb_driver(mcs_driver);
978