1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Freescale QUICC Engine USB Host Controller Driver
4 *
5 * Copyright (c) Freescale Semicondutor, Inc. 2006.
6 * Shlomi Gridish <gridish@freescale.com>
7 * Jerry Huang <Chang-Ming.Huang@freescale.com>
8 * Copyright (c) Logic Product Development, Inc. 2007
9 * Peter Barada <peterb@logicpd.com>
10 * Copyright (c) MontaVista Software, Inc. 2008.
11 * Anton Vorontsov <avorontsov@ru.mvista.com>
12 */
13
14 #include <linux/kernel.h>
15 #include <linux/types.h>
16 #include <linux/errno.h>
17 #include <linux/slab.h>
18 #include <linux/list.h>
19 #include <linux/io.h>
20 #include <linux/usb.h>
21 #include <linux/usb/hcd.h>
22 #include "fhci.h"
23
24 #define DUMMY_BD_BUFFER 0xdeadbeef
25 #define DUMMY2_BD_BUFFER 0xbaadf00d
26
27 /* Transaction Descriptors bits */
28 #define TD_R 0x8000 /* ready bit */
29 #define TD_W 0x2000 /* wrap bit */
30 #define TD_I 0x1000 /* interrupt on completion */
31 #define TD_L 0x0800 /* last */
32 #define TD_TC 0x0400 /* transmit CRC */
33 #define TD_CNF 0x0200 /* CNF - Must be always 1 */
34 #define TD_LSP 0x0100 /* Low-speed transaction */
35 #define TD_PID 0x00c0 /* packet id */
36 #define TD_RXER 0x0020 /* Rx error or not */
37
38 #define TD_NAK 0x0010 /* No ack. */
39 #define TD_STAL 0x0008 /* Stall received */
40 #define TD_TO 0x0004 /* time out */
41 #define TD_UN 0x0002 /* underrun */
42 #define TD_NO 0x0010 /* Rx Non Octet Aligned Packet */
43 #define TD_AB 0x0008 /* Frame Aborted */
44 #define TD_CR 0x0004 /* CRC Error */
45 #define TD_OV 0x0002 /* Overrun */
46 #define TD_BOV 0x0001 /* Buffer Overrun */
47
48 #define TD_ERRORS (TD_NAK | TD_STAL | TD_TO | TD_UN | \
49 TD_NO | TD_AB | TD_CR | TD_OV | TD_BOV)
50
51 #define TD_PID_DATA0 0x0080 /* Data 0 toggle */
52 #define TD_PID_DATA1 0x00c0 /* Data 1 toggle */
53 #define TD_PID_TOGGLE 0x00c0 /* Data 0/1 toggle mask */
54
55 #define TD_TOK_SETUP 0x0000
56 #define TD_TOK_OUT 0x4000
57 #define TD_TOK_IN 0x8000
58 #define TD_ISO 0x1000
59 #define TD_ENDP 0x0780
60 #define TD_ADDR 0x007f
61
62 #define TD_ENDP_SHIFT 7
63
64 struct usb_td {
65 __be16 status;
66 __be16 length;
67 __be32 buf_ptr;
68 __be16 extra;
69 __be16 reserved;
70 };
71
next_bd(struct usb_td __iomem * base,struct usb_td __iomem * td,u16 status)72 static struct usb_td __iomem *next_bd(struct usb_td __iomem *base,
73 struct usb_td __iomem *td,
74 u16 status)
75 {
76 if (status & TD_W)
77 return base;
78 else
79 return ++td;
80 }
81
fhci_push_dummy_bd(struct endpoint * ep)82 void fhci_push_dummy_bd(struct endpoint *ep)
83 {
84 if (!ep->already_pushed_dummy_bd) {
85 u16 td_status = in_be16(&ep->empty_td->status);
86
87 out_be32(&ep->empty_td->buf_ptr, DUMMY_BD_BUFFER);
88 /* get the next TD in the ring */
89 ep->empty_td = next_bd(ep->td_base, ep->empty_td, td_status);
90 ep->already_pushed_dummy_bd = true;
91 }
92 }
93
94 /* destroy an USB endpoint */
fhci_ep0_free(struct fhci_usb * usb)95 void fhci_ep0_free(struct fhci_usb *usb)
96 {
97 struct endpoint *ep;
98 int size;
99
100 ep = usb->ep0;
101 if (ep) {
102 if (ep->td_base)
103 cpm_muram_free(cpm_muram_offset(ep->td_base));
104
105 if (kfifo_initialized(&ep->conf_frame_Q)) {
106 size = cq_howmany(&ep->conf_frame_Q);
107 for (; size; size--) {
108 struct packet *pkt = cq_get(&ep->conf_frame_Q);
109
110 kfree(pkt);
111 }
112 cq_delete(&ep->conf_frame_Q);
113 }
114
115 if (kfifo_initialized(&ep->empty_frame_Q)) {
116 size = cq_howmany(&ep->empty_frame_Q);
117 for (; size; size--) {
118 struct packet *pkt = cq_get(&ep->empty_frame_Q);
119
120 kfree(pkt);
121 }
122 cq_delete(&ep->empty_frame_Q);
123 }
124
125 if (kfifo_initialized(&ep->dummy_packets_Q)) {
126 size = cq_howmany(&ep->dummy_packets_Q);
127 for (; size; size--) {
128 u8 *buff = cq_get(&ep->dummy_packets_Q);
129
130 kfree(buff);
131 }
132 cq_delete(&ep->dummy_packets_Q);
133 }
134
135 kfree(ep);
136 usb->ep0 = NULL;
137 }
138 }
139
140 /*
141 * create the endpoint structure
142 *
143 * arguments:
144 * usb A pointer to the data structure of the USB
145 * data_mem The data memory partition(BUS)
146 * ring_len TD ring length
147 */
fhci_create_ep(struct fhci_usb * usb,enum fhci_mem_alloc data_mem,u32 ring_len)148 u32 fhci_create_ep(struct fhci_usb *usb, enum fhci_mem_alloc data_mem,
149 u32 ring_len)
150 {
151 struct endpoint *ep;
152 struct usb_td __iomem *td;
153 unsigned long ep_offset;
154 char *err_for = "endpoint PRAM";
155 int ep_mem_size;
156 u32 i;
157
158 /* we need at least 3 TDs in the ring */
159 if (!(ring_len > 2)) {
160 fhci_err(usb->fhci, "illegal TD ring length parameters\n");
161 return -EINVAL;
162 }
163
164 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
165 if (!ep)
166 return -ENOMEM;
167
168 ep_mem_size = ring_len * sizeof(*td) + sizeof(struct fhci_ep_pram);
169 ep_offset = cpm_muram_alloc(ep_mem_size, 32);
170 if (IS_ERR_VALUE(ep_offset))
171 goto err;
172 ep->td_base = cpm_muram_addr(ep_offset);
173
174 /* zero all queue pointers */
175 if (cq_new(&ep->conf_frame_Q, ring_len + 2) ||
176 cq_new(&ep->empty_frame_Q, ring_len + 2) ||
177 cq_new(&ep->dummy_packets_Q, ring_len + 2)) {
178 err_for = "frame_queues";
179 goto err;
180 }
181
182 for (i = 0; i < (ring_len + 1); i++) {
183 struct packet *pkt;
184 u8 *buff;
185
186 pkt = kmalloc(sizeof(*pkt), GFP_KERNEL);
187 if (!pkt) {
188 err_for = "frame";
189 goto err;
190 }
191
192 buff = kmalloc_array(1028, sizeof(*buff), GFP_KERNEL);
193 if (!buff) {
194 kfree(pkt);
195 err_for = "buffer";
196 goto err;
197 }
198 cq_put(&ep->empty_frame_Q, pkt);
199 cq_put(&ep->dummy_packets_Q, buff);
200 }
201
202 /* we put the endpoint parameter RAM right behind the TD ring */
203 ep->ep_pram_ptr = (void __iomem *)ep->td_base + sizeof(*td) * ring_len;
204
205 ep->conf_td = ep->td_base;
206 ep->empty_td = ep->td_base;
207
208 ep->already_pushed_dummy_bd = false;
209
210 /* initialize tds */
211 td = ep->td_base;
212 for (i = 0; i < ring_len; i++) {
213 out_be32(&td->buf_ptr, 0);
214 out_be16(&td->status, 0);
215 out_be16(&td->length, 0);
216 out_be16(&td->extra, 0);
217 td++;
218 }
219 td--;
220 out_be16(&td->status, TD_W); /* for last TD set Wrap bit */
221 out_be16(&td->length, 0);
222
223 /* endpoint structure has been created */
224 usb->ep0 = ep;
225
226 return 0;
227 err:
228 fhci_ep0_free(usb);
229 kfree(ep);
230 fhci_err(usb->fhci, "no memory for the %s\n", err_for);
231 return -ENOMEM;
232 }
233
234 /*
235 * initialize the endpoint register according to the given parameters
236 *
237 * artuments:
238 * usb A pointer to the data strucutre of the USB
239 * ep A pointer to the endpoint structre
240 * data_mem The data memory partition(BUS)
241 */
fhci_init_ep_registers(struct fhci_usb * usb,struct endpoint * ep,enum fhci_mem_alloc data_mem)242 void fhci_init_ep_registers(struct fhci_usb *usb, struct endpoint *ep,
243 enum fhci_mem_alloc data_mem)
244 {
245 u8 rt;
246
247 /* set the endpoint registers according to the endpoint */
248 out_be16(&usb->fhci->regs->usb_usep[0],
249 USB_TRANS_CTR | USB_EP_MF | USB_EP_RTE);
250 out_be16(&usb->fhci->pram->ep_ptr[0],
251 cpm_muram_offset(ep->ep_pram_ptr));
252
253 rt = (BUS_MODE_BO_BE | BUS_MODE_GBL);
254 #ifdef MULTI_DATA_BUS
255 if (data_mem == MEM_SECONDARY)
256 rt |= BUS_MODE_DTB;
257 #endif
258 out_8(&ep->ep_pram_ptr->rx_func_code, rt);
259 out_8(&ep->ep_pram_ptr->tx_func_code, rt);
260 out_be16(&ep->ep_pram_ptr->rx_buff_len, 1028);
261 out_be16(&ep->ep_pram_ptr->rx_base, 0);
262 out_be16(&ep->ep_pram_ptr->tx_base, cpm_muram_offset(ep->td_base));
263 out_be16(&ep->ep_pram_ptr->rx_bd_ptr, 0);
264 out_be16(&ep->ep_pram_ptr->tx_bd_ptr, cpm_muram_offset(ep->td_base));
265 out_be32(&ep->ep_pram_ptr->tx_state, 0);
266 }
267
268 /*
269 * Collect the submitted frames and inform the application about them
270 * It is also preparing the TDs for new frames. If the Tx interrupts
271 * are disabled, the application should call that routine to get
272 * confirmation about the submitted frames. Otherwise, the routine is
273 * called from the interrupt service routine during the Tx interrupt.
274 * In that case the application is informed by calling the application
275 * specific 'fhci_transaction_confirm' routine
276 */
fhci_td_transaction_confirm(struct fhci_usb * usb)277 static void fhci_td_transaction_confirm(struct fhci_usb *usb)
278 {
279 struct endpoint *ep = usb->ep0;
280 struct packet *pkt;
281 struct usb_td __iomem *td;
282 u16 extra_data;
283 u16 td_status;
284 u16 td_length;
285 u32 buf;
286
287 /*
288 * collect transmitted BDs from the chip. The routine clears all BDs
289 * with R bit = 0 and the pointer to data buffer is not NULL, that is
290 * BDs which point to the transmitted data buffer
291 */
292 while (1) {
293 td = ep->conf_td;
294 td_status = in_be16(&td->status);
295 td_length = in_be16(&td->length);
296 buf = in_be32(&td->buf_ptr);
297 extra_data = in_be16(&td->extra);
298
299 /* check if the TD is empty */
300 if (!(!(td_status & TD_R) && ((td_status & ~TD_W) || buf)))
301 break;
302 /* check if it is a dummy buffer */
303 else if ((buf == DUMMY_BD_BUFFER) && !(td_status & ~TD_W))
304 break;
305
306 /* mark TD as empty */
307 clrbits16(&td->status, ~TD_W);
308 out_be16(&td->length, 0);
309 out_be32(&td->buf_ptr, 0);
310 out_be16(&td->extra, 0);
311 /* advance the TD pointer */
312 ep->conf_td = next_bd(ep->td_base, ep->conf_td, td_status);
313
314 /* check if it is a dummy buffer(type2) */
315 if ((buf == DUMMY2_BD_BUFFER) && !(td_status & ~TD_W))
316 continue;
317
318 pkt = cq_get(&ep->conf_frame_Q);
319 if (!pkt)
320 fhci_err(usb->fhci, "no frame to confirm\n");
321
322 if (td_status & TD_ERRORS) {
323 if (td_status & TD_RXER) {
324 if (td_status & TD_CR)
325 pkt->status = USB_TD_RX_ER_CRC;
326 else if (td_status & TD_AB)
327 pkt->status = USB_TD_RX_ER_BITSTUFF;
328 else if (td_status & TD_OV)
329 pkt->status = USB_TD_RX_ER_OVERUN;
330 else if (td_status & TD_BOV)
331 pkt->status = USB_TD_RX_DATA_OVERUN;
332 else if (td_status & TD_NO)
333 pkt->status = USB_TD_RX_ER_NONOCT;
334 else
335 fhci_err(usb->fhci, "illegal error "
336 "occurred\n");
337 } else if (td_status & TD_NAK)
338 pkt->status = USB_TD_TX_ER_NAK;
339 else if (td_status & TD_TO)
340 pkt->status = USB_TD_TX_ER_TIMEOUT;
341 else if (td_status & TD_UN)
342 pkt->status = USB_TD_TX_ER_UNDERUN;
343 else if (td_status & TD_STAL)
344 pkt->status = USB_TD_TX_ER_STALL;
345 else
346 fhci_err(usb->fhci, "illegal error occurred\n");
347 } else if ((extra_data & TD_TOK_IN) &&
348 pkt->len > td_length - CRC_SIZE) {
349 pkt->status = USB_TD_RX_DATA_UNDERUN;
350 }
351
352 if (extra_data & TD_TOK_IN)
353 pkt->len = td_length - CRC_SIZE;
354 else if (pkt->info & PKT_ZLP)
355 pkt->len = 0;
356 else
357 pkt->len = td_length;
358
359 fhci_transaction_confirm(usb, pkt);
360 }
361 }
362
363 /*
364 * Submitting a data frame to a specified endpoint of a USB device
365 * The frame is put in the driver's transmit queue for this endpoint
366 *
367 * Arguments:
368 * usb A pointer to the USB structure
369 * pkt A pointer to the user frame structure
370 * trans_type Transaction tyep - IN,OUT or SETUP
371 * dest_addr Device address - 0~127
372 * dest_ep Endpoint number of the device - 0~16
373 * trans_mode Pipe type - ISO,Interrupt,bulk or control
374 * dest_speed USB speed - Low speed or FULL speed
375 * data_toggle Data sequence toggle - 0 or 1
376 */
fhci_host_transaction(struct fhci_usb * usb,struct packet * pkt,enum fhci_ta_type trans_type,u8 dest_addr,u8 dest_ep,enum fhci_tf_mode trans_mode,enum fhci_speed dest_speed,u8 data_toggle)377 u32 fhci_host_transaction(struct fhci_usb *usb,
378 struct packet *pkt,
379 enum fhci_ta_type trans_type,
380 u8 dest_addr,
381 u8 dest_ep,
382 enum fhci_tf_mode trans_mode,
383 enum fhci_speed dest_speed, u8 data_toggle)
384 {
385 struct endpoint *ep = usb->ep0;
386 struct usb_td __iomem *td;
387 u16 extra_data;
388 u16 td_status;
389
390 fhci_usb_disable_interrupt(usb);
391 /* start from the next BD that should be filled */
392 td = ep->empty_td;
393 td_status = in_be16(&td->status);
394
395 if (td_status & TD_R && in_be16(&td->length)) {
396 /* if the TD is not free */
397 fhci_usb_enable_interrupt(usb);
398 return -1;
399 }
400
401 /* get the next TD in the ring */
402 ep->empty_td = next_bd(ep->td_base, ep->empty_td, td_status);
403 fhci_usb_enable_interrupt(usb);
404 pkt->priv_data = td;
405 out_be32(&td->buf_ptr, virt_to_phys(pkt->data));
406 /* sets up transaction parameters - addr,endp,dir,and type */
407 extra_data = (dest_ep << TD_ENDP_SHIFT) | dest_addr;
408 switch (trans_type) {
409 case FHCI_TA_IN:
410 extra_data |= TD_TOK_IN;
411 break;
412 case FHCI_TA_OUT:
413 extra_data |= TD_TOK_OUT;
414 break;
415 case FHCI_TA_SETUP:
416 extra_data |= TD_TOK_SETUP;
417 break;
418 }
419 if (trans_mode == FHCI_TF_ISO)
420 extra_data |= TD_ISO;
421 out_be16(&td->extra, extra_data);
422
423 /* sets up the buffer descriptor */
424 td_status = ((td_status & TD_W) | TD_R | TD_L | TD_I | TD_CNF);
425 if (!(pkt->info & PKT_NO_CRC))
426 td_status |= TD_TC;
427
428 switch (trans_type) {
429 case FHCI_TA_IN:
430 if (data_toggle)
431 pkt->info |= PKT_PID_DATA1;
432 else
433 pkt->info |= PKT_PID_DATA0;
434 break;
435 default:
436 if (data_toggle) {
437 td_status |= TD_PID_DATA1;
438 pkt->info |= PKT_PID_DATA1;
439 } else {
440 td_status |= TD_PID_DATA0;
441 pkt->info |= PKT_PID_DATA0;
442 }
443 break;
444 }
445
446 if ((dest_speed == FHCI_LOW_SPEED) &&
447 (usb->port_status == FHCI_PORT_FULL))
448 td_status |= TD_LSP;
449
450 out_be16(&td->status, td_status);
451
452 /* set up buffer length */
453 if (trans_type == FHCI_TA_IN)
454 out_be16(&td->length, pkt->len + CRC_SIZE);
455 else
456 out_be16(&td->length, pkt->len);
457
458 /* put the frame to the confirmation queue */
459 cq_put(&ep->conf_frame_Q, pkt);
460
461 if (cq_howmany(&ep->conf_frame_Q) == 1)
462 out_8(&usb->fhci->regs->usb_uscom, USB_CMD_STR_FIFO);
463
464 return 0;
465 }
466
467 /* Reset the Tx BD ring */
fhci_flush_bds(struct fhci_usb * usb)468 void fhci_flush_bds(struct fhci_usb *usb)
469 {
470 u16 extra_data;
471 u16 td_status;
472 u32 buf;
473 struct usb_td __iomem *td;
474 struct endpoint *ep = usb->ep0;
475
476 td = ep->td_base;
477 while (1) {
478 td_status = in_be16(&td->status);
479 buf = in_be32(&td->buf_ptr);
480 extra_data = in_be16(&td->extra);
481
482 /* if the TD is not empty - we'll confirm it as Timeout */
483 if (td_status & TD_R)
484 out_be16(&td->status, (td_status & ~TD_R) | TD_TO);
485 /* if this TD is dummy - let's skip this TD */
486 else if (in_be32(&td->buf_ptr) == DUMMY_BD_BUFFER)
487 out_be32(&td->buf_ptr, DUMMY2_BD_BUFFER);
488 /* if this is the last TD - break */
489 if (td_status & TD_W)
490 break;
491
492 td++;
493 }
494
495 fhci_td_transaction_confirm(usb);
496
497 td = ep->td_base;
498 do {
499 out_be16(&td->status, 0);
500 out_be16(&td->length, 0);
501 out_be32(&td->buf_ptr, 0);
502 out_be16(&td->extra, 0);
503 td++;
504 } while (!(in_be16(&td->status) & TD_W));
505 out_be16(&td->status, TD_W); /* for last TD set Wrap bit */
506 out_be16(&td->length, 0);
507 out_be32(&td->buf_ptr, 0);
508 out_be16(&td->extra, 0);
509
510 out_be16(&ep->ep_pram_ptr->tx_bd_ptr,
511 in_be16(&ep->ep_pram_ptr->tx_base));
512 out_be32(&ep->ep_pram_ptr->tx_state, 0);
513 out_be16(&ep->ep_pram_ptr->tx_cnt, 0);
514 ep->empty_td = ep->td_base;
515 ep->conf_td = ep->td_base;
516 }
517
518 /*
519 * Flush all transmitted packets from TDs in the actual frame.
520 * This routine is called when something wrong with the controller and
521 * we want to get rid of the actual frame and start again next frame
522 */
fhci_flush_actual_frame(struct fhci_usb * usb)523 void fhci_flush_actual_frame(struct fhci_usb *usb)
524 {
525 u8 mode;
526 u16 tb_ptr;
527 u16 extra_data;
528 u16 td_status;
529 u32 buf_ptr;
530 struct usb_td __iomem *td;
531 struct endpoint *ep = usb->ep0;
532
533 /* disable the USB controller */
534 mode = in_8(&usb->fhci->regs->usb_usmod);
535 out_8(&usb->fhci->regs->usb_usmod, mode & ~USB_MODE_EN);
536
537 tb_ptr = in_be16(&ep->ep_pram_ptr->tx_bd_ptr);
538 td = cpm_muram_addr(tb_ptr);
539 td_status = in_be16(&td->status);
540 buf_ptr = in_be32(&td->buf_ptr);
541 extra_data = in_be16(&td->extra);
542 do {
543 if (td_status & TD_R) {
544 out_be16(&td->status, (td_status & ~TD_R) | TD_TO);
545 } else {
546 out_be32(&td->buf_ptr, 0);
547 ep->already_pushed_dummy_bd = false;
548 break;
549 }
550
551 /* advance the TD pointer */
552 td = next_bd(ep->td_base, td, td_status);
553 td_status = in_be16(&td->status);
554 buf_ptr = in_be32(&td->buf_ptr);
555 extra_data = in_be16(&td->extra);
556 } while ((td_status & TD_R) || buf_ptr);
557
558 fhci_td_transaction_confirm(usb);
559
560 out_be16(&ep->ep_pram_ptr->tx_bd_ptr,
561 in_be16(&ep->ep_pram_ptr->tx_base));
562 out_be32(&ep->ep_pram_ptr->tx_state, 0);
563 out_be16(&ep->ep_pram_ptr->tx_cnt, 0);
564 ep->empty_td = ep->td_base;
565 ep->conf_td = ep->td_base;
566
567 usb->actual_frame->frame_status = FRAME_TIMER_END_TRANSMISSION;
568
569 /* reset the event register */
570 out_be16(&usb->fhci->regs->usb_usber, 0xffff);
571 /* enable the USB controller */
572 out_8(&usb->fhci->regs->usb_usmod, mode | USB_MODE_EN);
573 }
574
575 /* handles Tx confirm and Tx error interrupt */
fhci_tx_conf_interrupt(struct fhci_usb * usb)576 void fhci_tx_conf_interrupt(struct fhci_usb *usb)
577 {
578 fhci_td_transaction_confirm(usb);
579
580 /*
581 * Schedule another transaction to this frame only if we have
582 * already confirmed all transaction in the frame.
583 */
584 if (((fhci_get_sof_timer_count(usb) < usb->max_frame_usage) ||
585 (usb->actual_frame->frame_status & FRAME_END_TRANSMISSION)) &&
586 (list_empty(&usb->actual_frame->tds_list)))
587 fhci_schedule_transactions(usb);
588 }
589
fhci_host_transmit_actual_frame(struct fhci_usb * usb)590 void fhci_host_transmit_actual_frame(struct fhci_usb *usb)
591 {
592 u16 tb_ptr;
593 u16 td_status;
594 struct usb_td __iomem *td;
595 struct endpoint *ep = usb->ep0;
596
597 tb_ptr = in_be16(&ep->ep_pram_ptr->tx_bd_ptr);
598 td = cpm_muram_addr(tb_ptr);
599
600 if (in_be32(&td->buf_ptr) == DUMMY_BD_BUFFER) {
601 struct usb_td __iomem *old_td = td;
602
603 ep->already_pushed_dummy_bd = false;
604 td_status = in_be16(&td->status);
605 /* gets the next TD in the ring */
606 td = next_bd(ep->td_base, td, td_status);
607 tb_ptr = cpm_muram_offset(td);
608 out_be16(&ep->ep_pram_ptr->tx_bd_ptr, tb_ptr);
609
610 /* start transmit only if we have something in the TDs */
611 if (in_be16(&td->status) & TD_R)
612 out_8(&usb->fhci->regs->usb_uscom, USB_CMD_STR_FIFO);
613
614 if (in_be32(&ep->conf_td->buf_ptr) == DUMMY_BD_BUFFER) {
615 out_be32(&old_td->buf_ptr, 0);
616 ep->conf_td = next_bd(ep->td_base, ep->conf_td,
617 td_status);
618 } else {
619 out_be32(&old_td->buf_ptr, DUMMY2_BD_BUFFER);
620 }
621 }
622 }
623
