xref: /openbmc/u-boot/drivers/usb/musb/musb_hcd.c (revision a89c33db)
1 /*
2  * Mentor USB OTG Core host controller driver.
3  *
4  * Copyright (c) 2008 Texas Instruments
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
19  * MA 02111-1307 USA
20  *
21  * Author: Thomas Abraham t-abraham@ti.com, Texas Instruments
22  */
23 
24 #include <common.h>
25 #include "musb_hcd.h"
26 
27 /* MSC control transfers */
28 #define USB_MSC_BBB_RESET 	0xFF
29 #define USB_MSC_BBB_GET_MAX_LUN	0xFE
30 
31 /* Endpoint configuration information */
32 static struct musb_epinfo epinfo[3] = {
33 	{MUSB_BULK_EP, 1, 512}, /* EP1 - Bluk Out - 512 Bytes */
34 	{MUSB_BULK_EP, 0, 512}, /* EP1 - Bluk In  - 512 Bytes */
35 	{MUSB_INTR_EP, 0, 64}   /* EP2 - Interrupt IN - 64 Bytes */
36 };
37 
38 /*
39  * This function writes the data toggle value.
40  */
41 static void write_toggle(struct usb_device *dev, u8 ep, u8 dir_out)
42 {
43 	u16 toggle = usb_gettoggle(dev, ep, dir_out);
44 	u16 csr;
45 
46 	if (dir_out) {
47 		if (!toggle)
48 			writew(MUSB_TXCSR_CLRDATATOG, &musbr->txcsr);
49 		else {
50 			csr = readw(&musbr->txcsr);
51 			csr |= MUSB_TXCSR_H_WR_DATATOGGLE;
52 			writew(csr, &musbr->txcsr);
53 			csr |= (toggle << MUSB_TXCSR_H_DATATOGGLE_SHIFT);
54 			writew(csr, &musbr->txcsr);
55 		}
56 	} else {
57 		if (!toggle)
58 			writew(MUSB_RXCSR_CLRDATATOG, &musbr->rxcsr);
59 		else {
60 			csr = readw(&musbr->rxcsr);
61 			csr |= MUSB_RXCSR_H_WR_DATATOGGLE;
62 			writew(csr, &musbr->rxcsr);
63 			csr |= (toggle << MUSB_S_RXCSR_H_DATATOGGLE);
64 			writew(csr, &musbr->rxcsr);
65 		}
66 	}
67 }
68 
69 /*
70  * This function checks if RxStall has occured on the endpoint. If a RxStall
71  * has occured, the RxStall is cleared and 1 is returned. If RxStall has
72  * not occured, 0 is returned.
73  */
74 static u8 check_stall(u8 ep, u8 dir_out)
75 {
76 	u16 csr;
77 
78 	/* For endpoint 0 */
79 	if (!ep) {
80 		csr = readw(&musbr->txcsr);
81 		if (csr & MUSB_CSR0_H_RXSTALL) {
82 			csr &= ~MUSB_CSR0_H_RXSTALL;
83 			writew(csr, &musbr->txcsr);
84 			return 1;
85 		}
86 	} else { /* For non-ep0 */
87 		if (dir_out) { /* is it tx ep */
88 			csr = readw(&musbr->txcsr);
89 			if (csr & MUSB_TXCSR_H_RXSTALL) {
90 				csr &= ~MUSB_TXCSR_H_RXSTALL;
91 				writew(csr, &musbr->txcsr);
92 				return 1;
93 			}
94 		} else { /* is it rx ep */
95 			csr = readw(&musbr->rxcsr);
96 			if (csr & MUSB_RXCSR_H_RXSTALL) {
97 				csr &= ~MUSB_RXCSR_H_RXSTALL;
98 				writew(csr, &musbr->rxcsr);
99 				return 1;
100 			}
101 		}
102 	}
103 	return 0;
104 }
105 
106 /*
107  * waits until ep0 is ready. Returns 0 if ep is ready, -1 for timeout
108  * error and -2 for stall.
109  */
110 static int wait_until_ep0_ready(struct usb_device *dev, u32 bit_mask)
111 {
112 	u16 csr;
113 	int result = 1;
114 
115 	while (result > 0) {
116 		csr = readw(&musbr->txcsr);
117 		if (csr & MUSB_CSR0_H_ERROR) {
118 			csr &= ~MUSB_CSR0_H_ERROR;
119 			writew(csr, &musbr->txcsr);
120 			dev->status = USB_ST_CRC_ERR;
121 			result = -1;
122 			break;
123 		}
124 
125 		switch (bit_mask) {
126 		case MUSB_CSR0_TXPKTRDY:
127 			if (!(csr & MUSB_CSR0_TXPKTRDY)) {
128 				if (check_stall(MUSB_CONTROL_EP, 0)) {
129 					dev->status = USB_ST_STALLED;
130 					result = -2;
131 				} else
132 					result = 0;
133 			}
134 			break;
135 
136 		case MUSB_CSR0_RXPKTRDY:
137 			if (check_stall(MUSB_CONTROL_EP, 0)) {
138 				dev->status = USB_ST_STALLED;
139 				result = -2;
140 			} else
141 				if (csr & MUSB_CSR0_RXPKTRDY)
142 					result = 0;
143 			break;
144 
145 		case MUSB_CSR0_H_REQPKT:
146 			if (!(csr & MUSB_CSR0_H_REQPKT)) {
147 				if (check_stall(MUSB_CONTROL_EP, 0)) {
148 					dev->status = USB_ST_STALLED;
149 					result = -2;
150 				} else
151 					result = 0;
152 			}
153 			break;
154 		}
155 	}
156 	return result;
157 }
158 
159 /*
160  * waits until tx ep is ready. Returns 1 when ep is ready and 0 on error.
161  */
162 static u8 wait_until_txep_ready(struct usb_device *dev, u8 ep)
163 {
164 	u16 csr;
165 
166 	do {
167 		if (check_stall(ep, 1)) {
168 			dev->status = USB_ST_STALLED;
169 			return 0;
170 		}
171 
172 		csr = readw(&musbr->txcsr);
173 		if (csr & MUSB_TXCSR_H_ERROR) {
174 			dev->status = USB_ST_CRC_ERR;
175 			return 0;
176 		}
177 	} while (csr & MUSB_TXCSR_TXPKTRDY);
178 	return 1;
179 }
180 
181 /*
182  * waits until rx ep is ready. Returns 1 when ep is ready and 0 on error.
183  */
184 static u8 wait_until_rxep_ready(struct usb_device *dev, u8 ep)
185 {
186 	u16 csr;
187 
188 	do {
189 		if (check_stall(ep, 0)) {
190 			dev->status = USB_ST_STALLED;
191 			return 0;
192 		}
193 
194 		csr = readw(&musbr->rxcsr);
195 		if (csr & MUSB_RXCSR_H_ERROR) {
196 			dev->status = USB_ST_CRC_ERR;
197 			return 0;
198 		}
199 	} while (!(csr & MUSB_RXCSR_RXPKTRDY));
200 	return 1;
201 }
202 
203 /*
204  * This function performs the setup phase of the control transfer
205  */
206 static int ctrlreq_setup_phase(struct usb_device *dev, struct devrequest *setup)
207 {
208 	int result;
209 	u16 csr;
210 
211 	/* write the control request to ep0 fifo */
212 	write_fifo(MUSB_CONTROL_EP, sizeof(struct devrequest), (void *)setup);
213 
214 	/* enable transfer of setup packet */
215 	csr = readw(&musbr->txcsr);
216 	csr |= (MUSB_CSR0_TXPKTRDY|MUSB_CSR0_H_SETUPPKT);
217 	writew(csr, &musbr->txcsr);
218 
219 	/* wait until the setup packet is transmitted */
220 	result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
221 	dev->act_len = 0;
222 	return result;
223 }
224 
225 /*
226  * This function handles the control transfer in data phase
227  */
228 static int ctrlreq_in_data_phase(struct usb_device *dev, u32 len, void *buffer)
229 {
230 	u16 csr;
231 	u32 rxlen = 0;
232 	u32 nextlen = 0;
233 	u8  maxpktsize = (1 << dev->maxpacketsize) * 8;
234 	u8  *rxbuff = (u8 *)buffer;
235 	u8  rxedlength;
236 	int result;
237 
238 	while (rxlen < len) {
239 		/* Determine the next read length */
240 		nextlen = ((len-rxlen) > maxpktsize) ? maxpktsize : (len-rxlen);
241 
242 		/* Set the ReqPkt bit */
243 		csr = readw(&musbr->txcsr);
244 		writew(csr | MUSB_CSR0_H_REQPKT, &musbr->txcsr);
245 		result = wait_until_ep0_ready(dev, MUSB_CSR0_RXPKTRDY);
246 		if (result < 0)
247 			return result;
248 
249 		/* Actual number of bytes received by usb */
250 		rxedlength = readb(&musbr->rxcount);
251 
252 		/* Read the data from the RxFIFO */
253 		read_fifo(MUSB_CONTROL_EP, rxedlength, &rxbuff[rxlen]);
254 
255 		/* Clear the RxPktRdy Bit */
256 		csr = readw(&musbr->txcsr);
257 		csr &= ~MUSB_CSR0_RXPKTRDY;
258 		writew(csr, &musbr->txcsr);
259 
260 		/* short packet? */
261 		if (rxedlength != nextlen) {
262 			dev->act_len += rxedlength;
263 			break;
264 		}
265 		rxlen += nextlen;
266 		dev->act_len = rxlen;
267 	}
268 	return 0;
269 }
270 
271 /*
272  * This function handles the control transfer out data phase
273  */
274 static int ctrlreq_out_data_phase(struct usb_device *dev, u32 len, void *buffer)
275 {
276 	u16 csr;
277 	u32 txlen = 0;
278 	u32 nextlen = 0;
279 	u8  maxpktsize = (1 << dev->maxpacketsize) * 8;
280 	u8  *txbuff = (u8 *)buffer;
281 	int result = 0;
282 
283 	while (txlen < len) {
284 		/* Determine the next write length */
285 		nextlen = ((len-txlen) > maxpktsize) ? maxpktsize : (len-txlen);
286 
287 		/* Load the data to send in FIFO */
288 		write_fifo(MUSB_CONTROL_EP, txlen, &txbuff[txlen]);
289 
290 		/* Set TXPKTRDY bit */
291 		csr = readw(&musbr->txcsr);
292 		writew(csr | MUSB_CSR0_H_DIS_PING | MUSB_CSR0_TXPKTRDY,
293 					&musbr->txcsr);
294 		result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
295 		if (result < 0)
296 			break;
297 
298 		txlen += nextlen;
299 		dev->act_len = txlen;
300 	}
301 	return result;
302 }
303 
304 /*
305  * This function handles the control transfer out status phase
306  */
307 static int ctrlreq_out_status_phase(struct usb_device *dev)
308 {
309 	u16 csr;
310 	int result;
311 
312 	/* Set the StatusPkt bit */
313 	csr = readw(&musbr->txcsr);
314 	csr |= (MUSB_CSR0_H_DIS_PING | MUSB_CSR0_TXPKTRDY |
315 			MUSB_CSR0_H_STATUSPKT);
316 	writew(csr, &musbr->txcsr);
317 
318 	/* Wait until TXPKTRDY bit is cleared */
319 	result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
320 	return result;
321 }
322 
323 /*
324  * This function handles the control transfer in status phase
325  */
326 static int ctrlreq_in_status_phase(struct usb_device *dev)
327 {
328 	u16 csr;
329 	int result;
330 
331 	/* Set the StatusPkt bit and ReqPkt bit */
332 	csr = MUSB_CSR0_H_DIS_PING | MUSB_CSR0_H_REQPKT | MUSB_CSR0_H_STATUSPKT;
333 	writew(csr, &musbr->txcsr);
334 	result = wait_until_ep0_ready(dev, MUSB_CSR0_H_REQPKT);
335 
336 	/* clear StatusPkt bit and RxPktRdy bit */
337 	csr = readw(&musbr->txcsr);
338 	csr &= ~(MUSB_CSR0_RXPKTRDY | MUSB_CSR0_H_STATUSPKT);
339 	writew(csr, &musbr->txcsr);
340 	return result;
341 }
342 
343 /*
344  * determines the speed of the device (High/Full/Slow)
345  */
346 static u8 get_dev_speed(struct usb_device *dev)
347 {
348 	return (dev->speed & USB_SPEED_HIGH) ? MUSB_TYPE_SPEED_HIGH :
349 		((dev->speed & USB_SPEED_LOW) ? MUSB_TYPE_SPEED_LOW :
350 						MUSB_TYPE_SPEED_FULL);
351 }
352 
353 /*
354  * configure the hub address and the port address.
355  */
356 static void config_hub_port(struct usb_device *dev, u8 ep)
357 {
358 	u8 chid;
359 	u8 hub;
360 
361 	/* Find out the nearest parent which is high speed */
362 	while (dev->parent->parent != NULL)
363 		if (get_dev_speed(dev->parent) !=  MUSB_TYPE_SPEED_HIGH)
364 			dev = dev->parent;
365 		else
366 			break;
367 
368 	/* determine the port address at that hub */
369 	hub = dev->parent->devnum;
370 	for (chid = 0; chid < USB_MAXCHILDREN; chid++)
371 		if (dev->parent->children[chid] == dev)
372 			break;
373 
374 	/* configure the hub address and the port address */
375 	writeb(hub, &musbr->tar[ep].txhubaddr);
376 	writeb((chid + 1), &musbr->tar[ep].txhubport);
377 	writeb(hub, &musbr->tar[ep].rxhubaddr);
378 	writeb((chid + 1), &musbr->tar[ep].rxhubport);
379 }
380 
381 /*
382  * do a control transfer
383  */
384 int submit_control_msg(struct usb_device *dev, unsigned long pipe, void *buffer,
385 			int len, struct devrequest *setup)
386 {
387 	int devnum = usb_pipedevice(pipe);
388 	u16 csr;
389 	u8  devspeed;
390 
391 	/* select control endpoint */
392 	writeb(MUSB_CONTROL_EP, &musbr->index);
393 	csr = readw(&musbr->txcsr);
394 
395 	/* target addr and (for multipoint) hub addr/port */
396 	writeb(devnum, &musbr->tar[MUSB_CONTROL_EP].txfuncaddr);
397 	writeb(devnum, &musbr->tar[MUSB_CONTROL_EP].rxfuncaddr);
398 
399 	/* configure the hub address and the port number as required */
400 	devspeed = get_dev_speed(dev);
401 	if ((musb_ishighspeed()) && (dev->parent != NULL) &&
402 		(devspeed != MUSB_TYPE_SPEED_HIGH)) {
403 		config_hub_port(dev, MUSB_CONTROL_EP);
404 		writeb(devspeed << 6, &musbr->txtype);
405 	} else {
406 		writeb(musb_cfg.musb_speed << 6, &musbr->txtype);
407 		writeb(0, &musbr->tar[MUSB_CONTROL_EP].txhubaddr);
408 		writeb(0, &musbr->tar[MUSB_CONTROL_EP].txhubport);
409 		writeb(0, &musbr->tar[MUSB_CONTROL_EP].rxhubaddr);
410 		writeb(0, &musbr->tar[MUSB_CONTROL_EP].rxhubport);
411 	}
412 
413 	/* Control transfer setup phase */
414 	if (ctrlreq_setup_phase(dev, setup) < 0)
415 		return 0;
416 
417 	switch (setup->request) {
418 	case USB_REQ_GET_DESCRIPTOR:
419 	case USB_REQ_GET_CONFIGURATION:
420 	case USB_REQ_GET_INTERFACE:
421 	case USB_REQ_GET_STATUS:
422 	case USB_MSC_BBB_GET_MAX_LUN:
423 		/* control transfer in-data-phase */
424 		if (ctrlreq_in_data_phase(dev, len, buffer) < 0)
425 			return 0;
426 		/* control transfer out-status-phase */
427 		if (ctrlreq_out_status_phase(dev) < 0)
428 			return 0;
429 		break;
430 
431 	case USB_REQ_SET_ADDRESS:
432 	case USB_REQ_SET_CONFIGURATION:
433 	case USB_REQ_SET_FEATURE:
434 	case USB_REQ_SET_INTERFACE:
435 	case USB_REQ_CLEAR_FEATURE:
436 	case USB_MSC_BBB_RESET:
437 		/* control transfer in status phase */
438 		if (ctrlreq_in_status_phase(dev) < 0)
439 			return 0;
440 		break;
441 
442 	case USB_REQ_SET_DESCRIPTOR:
443 		/* control transfer out data phase */
444 		if (ctrlreq_out_data_phase(dev, len, buffer) < 0)
445 			return 0;
446 		/* control transfer in status phase */
447 		if (ctrlreq_in_status_phase(dev) < 0)
448 			return 0;
449 		break;
450 
451 	default:
452 		/* unhandled control transfer */
453 		return -1;
454 	}
455 
456 	dev->status = 0;
457 	dev->act_len = len;
458 	return len;
459 }
460 
461 /*
462  * do a bulk transfer
463  */
464 int submit_bulk_msg(struct usb_device *dev, unsigned long pipe,
465 					void *buffer, int len)
466 {
467 	int dir_out = usb_pipeout(pipe);
468 	int ep = usb_pipeendpoint(pipe);
469 	int devnum = usb_pipedevice(pipe);
470 	u8  type;
471 	u16 csr;
472 	u32 txlen = 0;
473 	u32 nextlen = 0;
474 	u8  devspeed;
475 
476 	/* select bulk endpoint */
477 	writeb(MUSB_BULK_EP, &musbr->index);
478 
479 	/* write the address of the device */
480 	if (dir_out)
481 		writeb(devnum, &musbr->tar[MUSB_BULK_EP].txfuncaddr);
482 	else
483 		writeb(devnum, &musbr->tar[MUSB_BULK_EP].rxfuncaddr);
484 
485 	/* configure the hub address and the port number as required */
486 	devspeed = get_dev_speed(dev);
487 	if ((musb_ishighspeed()) && (dev->parent != NULL) &&
488 		(devspeed != MUSB_TYPE_SPEED_HIGH)) {
489 		/*
490 		 * MUSB is in high speed and the destination device is full
491 		 * speed device. So configure the hub address and port
492 		 * address registers.
493 		 */
494 		config_hub_port(dev, MUSB_BULK_EP);
495 	} else {
496 		if (dir_out) {
497 			writeb(0, &musbr->tar[MUSB_BULK_EP].txhubaddr);
498 			writeb(0, &musbr->tar[MUSB_BULK_EP].txhubport);
499 		} else {
500 			writeb(0, &musbr->tar[MUSB_BULK_EP].rxhubaddr);
501 			writeb(0, &musbr->tar[MUSB_BULK_EP].rxhubport);
502 		}
503 		devspeed = musb_cfg.musb_speed;
504 	}
505 
506 	/* Write the saved toggle bit value */
507 	write_toggle(dev, ep, dir_out);
508 
509 	if (dir_out) { /* bulk-out transfer */
510 		/* Program the TxType register */
511 		type = (devspeed << MUSB_TYPE_SPEED_SHIFT) |
512 			   (MUSB_TYPE_PROTO_BULK << MUSB_TYPE_PROTO_SHIFT) |
513 			   (ep & MUSB_TYPE_REMOTE_END);
514 		writeb(type, &musbr->txtype);
515 
516 		/* Write maximum packet size to the TxMaxp register */
517 		writew(dev->epmaxpacketout[ep], &musbr->txmaxp);
518 		while (txlen < len) {
519 			nextlen = ((len-txlen) < dev->epmaxpacketout[ep]) ?
520 					(len-txlen) : dev->epmaxpacketout[ep];
521 
522 			/* Write the data to the FIFO */
523 			write_fifo(MUSB_BULK_EP, nextlen,
524 					(void *)(((u8 *)buffer) + txlen));
525 
526 			/* Set the TxPktRdy bit */
527 			csr = readw(&musbr->txcsr);
528 			writew(csr | MUSB_TXCSR_TXPKTRDY, &musbr->txcsr);
529 
530 			/* Wait until the TxPktRdy bit is cleared */
531 			if (!wait_until_txep_ready(dev, MUSB_BULK_EP)) {
532 				readw(&musbr->txcsr);
533 				usb_settoggle(dev, ep, dir_out,
534 				(csr >> MUSB_TXCSR_H_DATATOGGLE_SHIFT) & 1);
535 				dev->act_len = txlen;
536 				return 0;
537 			}
538 			txlen += nextlen;
539 		}
540 
541 		/* Keep a copy of the data toggle bit */
542 		csr = readw(&musbr->txcsr);
543 		usb_settoggle(dev, ep, dir_out,
544 				(csr >> MUSB_TXCSR_H_DATATOGGLE_SHIFT) & 1);
545 	} else { /* bulk-in transfer */
546 		/* Write the saved toggle bit value */
547 		write_toggle(dev, ep, dir_out);
548 
549 		/* Program the RxType register */
550 		type = (devspeed << MUSB_TYPE_SPEED_SHIFT) |
551 			   (MUSB_TYPE_PROTO_BULK << MUSB_TYPE_PROTO_SHIFT) |
552 			   (ep & MUSB_TYPE_REMOTE_END);
553 		writeb(type, &musbr->rxtype);
554 
555 		/* Write the maximum packet size to the RxMaxp register */
556 		writew(dev->epmaxpacketin[ep], &musbr->rxmaxp);
557 		while (txlen < len) {
558 			nextlen = ((len-txlen) < dev->epmaxpacketin[ep]) ?
559 					(len-txlen) : dev->epmaxpacketin[ep];
560 
561 			/* Set the ReqPkt bit */
562 			writew(MUSB_RXCSR_H_REQPKT, &musbr->rxcsr);
563 
564 			/* Wait until the RxPktRdy bit is set */
565 			if (!wait_until_rxep_ready(dev, MUSB_BULK_EP)) {
566 				csr = readw(&musbr->rxcsr);
567 				usb_settoggle(dev, ep, dir_out,
568 				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
569 				csr &= ~MUSB_RXCSR_RXPKTRDY;
570 				writew(csr, &musbr->rxcsr);
571 				dev->act_len = txlen;
572 				return 0;
573 			}
574 
575 			/* Read the data from the FIFO */
576 			read_fifo(MUSB_BULK_EP, nextlen,
577 					(void *)(((u8 *)buffer) + txlen));
578 
579 			/* Clear the RxPktRdy bit */
580 			csr =  readw(&musbr->rxcsr);
581 			csr &= ~MUSB_RXCSR_RXPKTRDY;
582 			writew(csr, &musbr->rxcsr);
583 			txlen += nextlen;
584 		}
585 
586 		/* Keep a copy of the data toggle bit */
587 		csr = readw(&musbr->rxcsr);
588 		usb_settoggle(dev, ep, dir_out,
589 				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
590 	}
591 
592 	/* bulk transfer is complete */
593 	dev->status = 0;
594 	dev->act_len = len;
595 	return 0;
596 }
597 
598 /*
599  * This function initializes the usb controller module.
600  */
601 int usb_lowlevel_init(void)
602 {
603 	u8  power;
604 	u32 timeout;
605 
606 	if (musb_platform_init() == -1)
607 		return -1;
608 
609 	/* Configure all the endpoint FIFO's and start usb controller */
610 	musbr = musb_cfg.regs;
611 	musb_configure_ep(&epinfo[0],
612 			sizeof(epinfo) / sizeof(struct musb_epinfo));
613 	musb_start();
614 
615 	/*
616 	 * Wait until musb is enabled in host mode with a timeout. There
617 	 * should be a usb device connected.
618 	 */
619 	timeout = musb_cfg.timeout;
620 	while (timeout--)
621 		if (readb(&musbr->devctl) & MUSB_DEVCTL_HM)
622 			break;
623 
624 	/* if musb core is not in host mode, then return */
625 	if (!timeout)
626 		return -1;
627 
628 	/* start usb bus reset */
629 	power = readb(&musbr->power);
630 	writeb(power | MUSB_POWER_RESET, &musbr->power);
631 
632 	/* After initiating a usb reset, wait for about 20ms to 30ms */
633 	udelay(30000);
634 
635 	/* stop usb bus reset */
636 	power = readb(&musbr->power);
637 	power &= ~MUSB_POWER_RESET;
638 	writeb(power, &musbr->power);
639 
640 	/* Determine if the connected device is a high/full/low speed device */
641 	musb_cfg.musb_speed = (readb(&musbr->power) & MUSB_POWER_HSMODE) ?
642 			MUSB_TYPE_SPEED_HIGH :
643 			((readb(&musbr->devctl) & MUSB_DEVCTL_FSDEV) ?
644 			MUSB_TYPE_SPEED_FULL : MUSB_TYPE_SPEED_LOW);
645 	return 0;
646 }
647 
648 /*
649  * This function stops the operation of the davinci usb module.
650  */
651 int usb_lowlevel_stop(void)
652 {
653 	/* Reset the USB module */
654 	musb_platform_deinit();
655 	writeb(0, &musbr->devctl);
656 	return 0;
657 }
658 
659 /*
660  * This function supports usb interrupt transfers. Currently, usb interrupt
661  * transfers are not supported.
662  */
663 int submit_int_msg(struct usb_device *dev, unsigned long pipe,
664 				void *buffer, int len, int interval)
665 {
666 	int dir_out = usb_pipeout(pipe);
667 	int ep = usb_pipeendpoint(pipe);
668 	int devnum = usb_pipedevice(pipe);
669 	u8  type;
670 	u16 csr;
671 	u32 txlen = 0;
672 	u32 nextlen = 0;
673 	u8  devspeed;
674 
675 	/* select interrupt endpoint */
676 	writeb(MUSB_INTR_EP, &musbr->index);
677 
678 	/* write the address of the device */
679 	if (dir_out)
680 		writeb(devnum, &musbr->tar[MUSB_INTR_EP].txfuncaddr);
681 	else
682 		writeb(devnum, &musbr->tar[MUSB_INTR_EP].rxfuncaddr);
683 
684 	/* configure the hub address and the port number as required */
685 	devspeed = get_dev_speed(dev);
686 	if ((musb_ishighspeed()) && (dev->parent != NULL) &&
687 		(devspeed != MUSB_TYPE_SPEED_HIGH)) {
688 		/*
689 		 * MUSB is in high speed and the destination device is full
690 		 * speed device. So configure the hub address and port
691 		 * address registers.
692 		 */
693 		config_hub_port(dev, MUSB_INTR_EP);
694 	} else {
695 		if (dir_out) {
696 			writeb(0, &musbr->tar[MUSB_INTR_EP].txhubaddr);
697 			writeb(0, &musbr->tar[MUSB_INTR_EP].txhubport);
698 		} else {
699 			writeb(0, &musbr->tar[MUSB_INTR_EP].rxhubaddr);
700 			writeb(0, &musbr->tar[MUSB_INTR_EP].rxhubport);
701 		}
702 		devspeed = musb_cfg.musb_speed;
703 	}
704 
705 	/* Write the saved toggle bit value */
706 	write_toggle(dev, ep, dir_out);
707 
708 	if (!dir_out) { /* intrrupt-in transfer */
709 		/* Write the saved toggle bit value */
710 		write_toggle(dev, ep, dir_out);
711 		writeb(interval, &musbr->rxinterval);
712 
713 		/* Program the RxType register */
714 		type = (devspeed << MUSB_TYPE_SPEED_SHIFT) |
715 			   (MUSB_TYPE_PROTO_INTR << MUSB_TYPE_PROTO_SHIFT) |
716 			   (ep & MUSB_TYPE_REMOTE_END);
717 		writeb(type, &musbr->rxtype);
718 
719 		/* Write the maximum packet size to the RxMaxp register */
720 		writew(dev->epmaxpacketin[ep], &musbr->rxmaxp);
721 
722 		while (txlen < len) {
723 			nextlen = ((len-txlen) < dev->epmaxpacketin[ep]) ?
724 					(len-txlen) : dev->epmaxpacketin[ep];
725 
726 			/* Set the ReqPkt bit */
727 			writew(MUSB_RXCSR_H_REQPKT, &musbr->rxcsr);
728 
729 			/* Wait until the RxPktRdy bit is set */
730 			if (!wait_until_rxep_ready(dev, MUSB_INTR_EP)) {
731 				csr = readw(&musbr->rxcsr);
732 				usb_settoggle(dev, ep, dir_out,
733 				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
734 				csr &= ~MUSB_RXCSR_RXPKTRDY;
735 				writew(csr, &musbr->rxcsr);
736 				dev->act_len = txlen;
737 				return 0;
738 			}
739 
740 			/* Read the data from the FIFO */
741 			read_fifo(MUSB_INTR_EP, nextlen,
742 					(void *)(((u8 *)buffer) + txlen));
743 
744 			/* Clear the RxPktRdy bit */
745 			csr =  readw(&musbr->rxcsr);
746 			csr &= ~MUSB_RXCSR_RXPKTRDY;
747 			writew(csr, &musbr->rxcsr);
748 			txlen += nextlen;
749 		}
750 
751 		/* Keep a copy of the data toggle bit */
752 		csr = readw(&musbr->rxcsr);
753 		usb_settoggle(dev, ep, dir_out,
754 				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
755 	}
756 
757 	/* interrupt transfer is complete */
758 	dev->irq_status = 0;
759 	dev->irq_act_len = len;
760 	dev->irq_handle(dev);
761 	dev->status = 0;
762 	dev->act_len = len;
763 	return 0;
764 }
765 
766 
767 #ifdef CONFIG_SYS_USB_EVENT_POLL
768 /*
769  * This function polls for USB keyboard data.
770  */
771 void usb_event_poll()
772 {
773 	device_t *dev;
774 	struct usb_device *usb_kbd_dev;
775 	struct usb_interface_descriptor *iface;
776 	struct usb_endpoint_descriptor *ep;
777 	int pipe;
778 	int maxp;
779 
780 	/* Get the pointer to USB Keyboard device pointer */
781 	dev = device_get_by_name("usbkbd");
782 	usb_kbd_dev = (struct usb_device *)dev->priv;
783 	iface = &usb_kbd_dev->config.if_desc[0];
784 	ep = &iface->ep_desc[0];
785 	pipe = usb_rcvintpipe(usb_kbd_dev, ep->bEndpointAddress);
786 
787 	/* Submit a interrupt transfer request */
788 	maxp = usb_maxpacket(usb_kbd_dev, pipe);
789 	usb_submit_int_msg(usb_kbd_dev, pipe, &new[0],
790 			maxp > 8 ? 8 : maxp, ep->bInterval);
791 }
792 #endif /* CONFIG_SYS_USB_EVENT_POLL */
793