xref: /openbmc/u-boot/drivers/usb/gadget/f_sdp.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * f_sdp.c -- USB HID Serial Download Protocol
4  *
5  * Copyright (C) 2017 Toradex
6  * Author: Stefan Agner <stefan.agner@toradex.com>
7  *
8  * This file implements the Serial Download Protocol (SDP) as specified in
9  * the i.MX 6 Reference Manual. The SDP is a USB HID based protocol and
10  * allows to download images directly to memory. The implementation
11  * works with the imx_loader (imx_usb) USB client software on host side.
12  *
13  * Not all commands are implemented, e.g. WRITE_REGISTER, DCD_WRITE and
14  * SKIP_DCD_HEADER are only stubs.
15  *
16  * Parts of the implementation are based on f_dfu and f_thor.
17  */
18 
19 #include <errno.h>
20 #include <common.h>
21 #include <console.h>
22 #include <malloc.h>
23 
24 #include <linux/usb/ch9.h>
25 #include <linux/usb/gadget.h>
26 #include <linux/usb/composite.h>
27 
28 #include <asm/io.h>
29 #include <g_dnl.h>
30 #include <sdp.h>
31 #include <spl.h>
32 #include <image.h>
33 #include <imximage.h>
34 #include <watchdog.h>
35 
36 #define HID_REPORT_ID_MASK	0x000000ff
37 
38 /*
39  * HID class requests
40  */
41 #define HID_REQ_GET_REPORT		0x01
42 #define HID_REQ_GET_IDLE		0x02
43 #define HID_REQ_GET_PROTOCOL		0x03
44 #define HID_REQ_SET_REPORT		0x09
45 #define HID_REQ_SET_IDLE		0x0A
46 #define HID_REQ_SET_PROTOCOL		0x0B
47 
48 #define HID_USAGE_PAGE_LEN		76
49 
50 struct hid_report {
51 	u8 usage_page[HID_USAGE_PAGE_LEN];
52 } __packed;
53 
54 #define SDP_READ_REGISTER	0x0101
55 #define SDP_WRITE_REGISTER	0x0202
56 #define SDP_WRITE_FILE		0x0404
57 #define SDP_ERROR_STATUS	0x0505
58 #define SDP_DCD_WRITE		0x0a0a
59 #define SDP_JUMP_ADDRESS	0x0b0b
60 #define SDP_SKIP_DCD_HEADER	0x0c0c
61 
62 #define SDP_SECURITY_CLOSED		0x12343412
63 #define SDP_SECURITY_OPEN		0x56787856
64 
65 #define SDP_WRITE_FILE_COMPLETE		0x88888888
66 #define SDP_WRITE_REGISTER_COMPLETE	0x128A8A12
67 #define SDP_SKIP_DCD_HEADER_COMPLETE	0x900DD009
68 #define SDP_ERROR_IMXHEADER		0x000a0533
69 
70 #define SDP_COMMAND_LEN		16
71 
72 struct sdp_command {
73 	u16 cmd;
74 	u32 addr;
75 	u8 format;
76 	u32 cnt;
77 	u32 data;
78 	u8 rsvd;
79 } __packed;
80 
81 enum sdp_state {
82 	SDP_STATE_IDLE,
83 	SDP_STATE_RX_DCD_DATA,
84 	SDP_STATE_RX_FILE_DATA,
85 	SDP_STATE_TX_SEC_CONF,
86 	SDP_STATE_TX_SEC_CONF_BUSY,
87 	SDP_STATE_TX_REGISTER,
88 	SDP_STATE_TX_REGISTER_BUSY,
89 	SDP_STATE_TX_STATUS,
90 	SDP_STATE_TX_STATUS_BUSY,
91 	SDP_STATE_JUMP,
92 };
93 
94 struct f_sdp {
95 	struct usb_function		usb_function;
96 
97 	struct usb_descriptor_header	**function;
98 
99 	u8				altsetting;
100 	enum sdp_state			state;
101 	enum sdp_state			next_state;
102 	u32				dnl_address;
103 	u32				dnl_bytes;
104 	u32				dnl_bytes_remaining;
105 	u32				jmp_address;
106 	bool				always_send_status;
107 	u32				error_status;
108 
109 	/* EP0 request */
110 	struct usb_request		*req;
111 
112 	/* EP1 IN */
113 	struct usb_ep			*in_ep;
114 	struct usb_request		*in_req;
115 
116 	bool				configuration_done;
117 };
118 
119 static struct f_sdp *sdp_func;
120 
121 static inline struct f_sdp *func_to_sdp(struct usb_function *f)
122 {
123 	return container_of(f, struct f_sdp, usb_function);
124 }
125 
126 static struct usb_interface_descriptor sdp_intf_runtime = {
127 	.bLength =		sizeof(sdp_intf_runtime),
128 	.bDescriptorType =	USB_DT_INTERFACE,
129 	.bAlternateSetting =	0,
130 	.bNumEndpoints =	1,
131 	.bInterfaceClass =	USB_CLASS_HID,
132 	.bInterfaceSubClass =	0,
133 	.bInterfaceProtocol =	0,
134 	/* .iInterface = DYNAMIC */
135 };
136 
137 /* HID configuration */
138 static struct usb_class_hid_descriptor sdp_hid_desc = {
139 	.bLength =		sizeof(sdp_hid_desc),
140 	.bDescriptorType =	USB_DT_CS_DEVICE,
141 
142 	.bcdCDC =		__constant_cpu_to_le16(0x0110),
143 	.bCountryCode =		0,
144 	.bNumDescriptors =	1,
145 
146 	.bDescriptorType0	= USB_DT_HID_REPORT,
147 	.wDescriptorLength0	= HID_USAGE_PAGE_LEN,
148 };
149 
150 static struct usb_endpoint_descriptor in_desc = {
151 	.bLength =		USB_DT_ENDPOINT_SIZE,
152 	.bDescriptorType =	USB_DT_ENDPOINT, /*USB_DT_CS_ENDPOINT*/
153 
154 	.bEndpointAddress =	1 | USB_DIR_IN,
155 	.bmAttributes =	USB_ENDPOINT_XFER_INT,
156 	.wMaxPacketSize =	64,
157 	.bInterval =		1,
158 };
159 
160 static struct usb_descriptor_header *sdp_runtime_descs[] = {
161 	(struct usb_descriptor_header *)&sdp_intf_runtime,
162 	(struct usb_descriptor_header *)&sdp_hid_desc,
163 	(struct usb_descriptor_header *)&in_desc,
164 	NULL,
165 };
166 
167 /* This is synchronized with what the SoC implementation reports */
168 static struct hid_report sdp_hid_report = {
169 	.usage_page = {
170 		0x06, 0x00, 0xff, /* Usage Page */
171 		0x09, 0x01, /* Usage (Pointer?) */
172 		0xa1, 0x01, /* Collection */
173 
174 		0x85, 0x01, /* Report ID */
175 		0x19, 0x01, /* Usage Minimum */
176 		0x29, 0x01, /* Usage Maximum */
177 		0x15, 0x00, /* Local Minimum */
178 		0x26, 0xFF, 0x00, /* Local Maximum? */
179 		0x75, 0x08, /* Report Size */
180 		0x95, 0x10, /* Report Count */
181 		0x91, 0x02, /* Output Data */
182 
183 		0x85, 0x02, /* Report ID */
184 		0x19, 0x01, /* Usage Minimum */
185 		0x29, 0x01, /* Usage Maximum */
186 		0x15, 0x00, /* Local Minimum */
187 		0x26, 0xFF, 0x00, /* Local Maximum? */
188 		0x75, 0x80, /* Report Size 128 */
189 		0x95, 0x40, /* Report Count */
190 		0x91, 0x02, /* Output Data */
191 
192 		0x85, 0x03, /* Report ID */
193 		0x19, 0x01, /* Usage Minimum */
194 		0x29, 0x01, /* Usage Maximum */
195 		0x15, 0x00, /* Local Minimum */
196 		0x26, 0xFF, 0x00, /* Local Maximum? */
197 		0x75, 0x08, /* Report Size 8 */
198 		0x95, 0x04, /* Report Count */
199 		0x81, 0x02, /* Input Data */
200 
201 		0x85, 0x04, /* Report ID */
202 		0x19, 0x01, /* Usage Minimum */
203 		0x29, 0x01, /* Usage Maximum */
204 		0x15, 0x00, /* Local Minimum */
205 		0x26, 0xFF, 0x00, /* Local Maximum? */
206 		0x75, 0x08, /* Report Size 8 */
207 		0x95, 0x40, /* Report Count */
208 		0x81, 0x02, /* Input Data */
209 		0xc0
210 	},
211 };
212 
213 static const char sdp_name[] = "Serial Downloader Protocol";
214 
215 /*
216  * static strings, in UTF-8
217  */
218 static struct usb_string strings_sdp_generic[] = {
219 	[0].s = sdp_name,
220 	{  }			/* end of list */
221 };
222 
223 static struct usb_gadget_strings stringtab_sdp_generic = {
224 	.language	= 0x0409,	/* en-us */
225 	.strings	= strings_sdp_generic,
226 };
227 
228 static struct usb_gadget_strings *sdp_generic_strings[] = {
229 	&stringtab_sdp_generic,
230 	NULL,
231 };
232 
233 static inline void *sdp_ptr(u32 val)
234 {
235 	return (void *)(uintptr_t)val;
236 }
237 
238 static void sdp_rx_command_complete(struct usb_ep *ep, struct usb_request *req)
239 {
240 	struct f_sdp *sdp = req->context;
241 	int status = req->status;
242 	u8 *data = req->buf;
243 	u8 report = data[0];
244 
245 	if (status != 0) {
246 		pr_err("Status: %d\n", status);
247 		return;
248 	}
249 
250 	if (report != 1) {
251 		pr_err("Unexpected report %d\n", report);
252 		return;
253 	}
254 
255 	struct sdp_command *cmd = req->buf + 1;
256 
257 	debug("%s: command: %04x, addr: %08x, cnt: %u\n",
258 	      __func__, be16_to_cpu(cmd->cmd),
259 	      be32_to_cpu(cmd->addr), be32_to_cpu(cmd->cnt));
260 
261 	switch (be16_to_cpu(cmd->cmd)) {
262 	case SDP_READ_REGISTER:
263 		sdp->always_send_status = false;
264 		sdp->error_status = 0x0;
265 
266 		sdp->state = SDP_STATE_TX_SEC_CONF;
267 		sdp->dnl_address = be32_to_cpu(cmd->addr);
268 		sdp->dnl_bytes_remaining = be32_to_cpu(cmd->cnt);
269 		sdp->next_state = SDP_STATE_TX_REGISTER;
270 		printf("Reading %d registers at 0x%08x... ",
271 		       sdp->dnl_bytes_remaining, sdp->dnl_address);
272 		break;
273 	case SDP_WRITE_FILE:
274 		sdp->always_send_status = true;
275 		sdp->error_status = SDP_WRITE_FILE_COMPLETE;
276 
277 		sdp->state = SDP_STATE_RX_FILE_DATA;
278 		sdp->dnl_address = be32_to_cpu(cmd->addr);
279 		sdp->dnl_bytes_remaining = be32_to_cpu(cmd->cnt);
280 		sdp->dnl_bytes = sdp->dnl_bytes_remaining;
281 		sdp->next_state = SDP_STATE_IDLE;
282 
283 		printf("Downloading file of size %d to 0x%08x... ",
284 		       sdp->dnl_bytes_remaining, sdp->dnl_address);
285 
286 		break;
287 	case SDP_ERROR_STATUS:
288 		sdp->always_send_status = true;
289 		sdp->error_status = 0;
290 
291 		sdp->state = SDP_STATE_TX_SEC_CONF;
292 		sdp->next_state = SDP_STATE_IDLE;
293 		break;
294 	case SDP_DCD_WRITE:
295 		sdp->always_send_status = true;
296 		sdp->error_status = SDP_WRITE_REGISTER_COMPLETE;
297 
298 		sdp->state = SDP_STATE_RX_DCD_DATA;
299 		sdp->dnl_bytes_remaining = be32_to_cpu(cmd->cnt);
300 		sdp->next_state = SDP_STATE_IDLE;
301 		break;
302 	case SDP_JUMP_ADDRESS:
303 		sdp->always_send_status = false;
304 		sdp->error_status = 0;
305 
306 		sdp->jmp_address = be32_to_cpu(cmd->addr);
307 		sdp->state = SDP_STATE_TX_SEC_CONF;
308 		sdp->next_state = SDP_STATE_JUMP;
309 		break;
310 	case SDP_SKIP_DCD_HEADER:
311 		sdp->always_send_status = true;
312 		sdp->error_status = SDP_SKIP_DCD_HEADER_COMPLETE;
313 
314 		/* Ignore command, DCD not supported anyway */
315 		sdp->state = SDP_STATE_TX_SEC_CONF;
316 		sdp->next_state = SDP_STATE_IDLE;
317 		break;
318 	default:
319 		pr_err("Unknown command: %04x\n", be16_to_cpu(cmd->cmd));
320 	}
321 }
322 
323 static void sdp_rx_data_complete(struct usb_ep *ep, struct usb_request *req)
324 {
325 	struct f_sdp *sdp = req->context;
326 	int status = req->status;
327 	u8 *data = req->buf;
328 	u8 report = data[0];
329 	int datalen = req->length - 1;
330 
331 	if (status != 0) {
332 		pr_err("Status: %d\n", status);
333 		return;
334 	}
335 
336 	if (report != 2) {
337 		pr_err("Unexpected report %d\n", report);
338 		return;
339 	}
340 
341 	if (sdp->dnl_bytes_remaining < datalen) {
342 		/*
343 		 * Some USB stacks require to send a complete buffer as
344 		 * specified in the HID descriptor. This leads to longer
345 		 * transfers than the file length, no problem for us.
346 		 */
347 		sdp->dnl_bytes_remaining = 0;
348 	} else {
349 		sdp->dnl_bytes_remaining -= datalen;
350 	}
351 
352 	if (sdp->state == SDP_STATE_RX_FILE_DATA) {
353 		memcpy(sdp_ptr(sdp->dnl_address), req->buf + 1, datalen);
354 		sdp->dnl_address += datalen;
355 	}
356 
357 	if (sdp->dnl_bytes_remaining)
358 		return;
359 
360 #ifndef CONFIG_SPL_BUILD
361 	env_set_hex("filesize", sdp->dnl_bytes);
362 #endif
363 	printf("done\n");
364 
365 	switch (sdp->state) {
366 	case SDP_STATE_RX_FILE_DATA:
367 		sdp->state = SDP_STATE_TX_SEC_CONF;
368 		break;
369 	case SDP_STATE_RX_DCD_DATA:
370 		sdp->state = SDP_STATE_TX_SEC_CONF;
371 		break;
372 	default:
373 		pr_err("Invalid state: %d\n", sdp->state);
374 	}
375 }
376 
377 static void sdp_tx_complete(struct usb_ep *ep, struct usb_request *req)
378 {
379 	struct f_sdp *sdp = req->context;
380 	int status = req->status;
381 
382 	if (status != 0) {
383 		pr_err("Status: %d\n", status);
384 		return;
385 	}
386 
387 	switch (sdp->state) {
388 	case SDP_STATE_TX_SEC_CONF_BUSY:
389 		/* Not all commands require status report */
390 		if (sdp->always_send_status || sdp->error_status)
391 			sdp->state = SDP_STATE_TX_STATUS;
392 		else
393 			sdp->state = sdp->next_state;
394 
395 		break;
396 	case SDP_STATE_TX_STATUS_BUSY:
397 		sdp->state = sdp->next_state;
398 		break;
399 	case SDP_STATE_TX_REGISTER_BUSY:
400 		if (sdp->dnl_bytes_remaining)
401 			sdp->state = SDP_STATE_TX_REGISTER;
402 		else
403 			sdp->state = SDP_STATE_IDLE;
404 		break;
405 	default:
406 		pr_err("Wrong State: %d\n", sdp->state);
407 		sdp->state = SDP_STATE_IDLE;
408 		break;
409 	}
410 	debug("%s complete --> %d, %d/%d\n", ep->name,
411 	      status, req->actual, req->length);
412 }
413 
414 static int sdp_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
415 {
416 	struct usb_gadget *gadget = f->config->cdev->gadget;
417 	struct usb_request *req = f->config->cdev->req;
418 	struct f_sdp *sdp = f->config->cdev->req->context;
419 	u16 len = le16_to_cpu(ctrl->wLength);
420 	u16 w_value = le16_to_cpu(ctrl->wValue);
421 	int value = 0;
422 	u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
423 
424 	debug("w_value: 0x%04x len: 0x%04x\n", w_value, len);
425 	debug("req_type: 0x%02x ctrl->bRequest: 0x%02x sdp->state: %d\n",
426 	      req_type, ctrl->bRequest, sdp->state);
427 
428 	if (req_type == USB_TYPE_STANDARD) {
429 		if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR) {
430 			/* Send HID report descriptor */
431 			value = min(len, (u16) sizeof(sdp_hid_report));
432 			memcpy(req->buf, &sdp_hid_report, value);
433 			sdp->configuration_done = true;
434 		}
435 	}
436 
437 	if (req_type == USB_TYPE_CLASS) {
438 		int report = w_value & HID_REPORT_ID_MASK;
439 
440 		/* HID (SDP) request */
441 		switch (ctrl->bRequest) {
442 		case HID_REQ_SET_REPORT:
443 			switch (report) {
444 			case 1:
445 				value = SDP_COMMAND_LEN + 1;
446 				req->complete = sdp_rx_command_complete;
447 				break;
448 			case 2:
449 				value = len;
450 				req->complete = sdp_rx_data_complete;
451 				break;
452 			}
453 		}
454 	}
455 
456 	if (value >= 0) {
457 		req->length = value;
458 		req->zero = value < len;
459 		value = usb_ep_queue(gadget->ep0, req, 0);
460 		if (value < 0) {
461 			debug("ep_queue --> %d\n", value);
462 			req->status = 0;
463 		}
464 	}
465 
466 	return value;
467 }
468 
469 static int sdp_bind(struct usb_configuration *c, struct usb_function *f)
470 {
471 	struct usb_gadget *gadget = c->cdev->gadget;
472 	struct usb_composite_dev *cdev = c->cdev;
473 	struct f_sdp *sdp = func_to_sdp(f);
474 	int rv = 0, id;
475 
476 	id = usb_interface_id(c, f);
477 	if (id < 0)
478 		return id;
479 	sdp_intf_runtime.bInterfaceNumber = id;
480 
481 	struct usb_ep *ep;
482 
483 	/* allocate instance-specific endpoints */
484 	ep = usb_ep_autoconfig(gadget, &in_desc);
485 	if (!ep) {
486 		rv = -ENODEV;
487 		goto error;
488 	}
489 
490 	sdp->in_ep = ep; /* Store IN EP for enabling @ setup */
491 
492 	cdev->req->context = sdp;
493 
494 error:
495 	return rv;
496 }
497 
498 static void sdp_unbind(struct usb_configuration *c, struct usb_function *f)
499 {
500 	free(sdp_func);
501 	sdp_func = NULL;
502 }
503 
504 static struct usb_request *alloc_ep_req(struct usb_ep *ep, unsigned length)
505 {
506 	struct usb_request *req;
507 
508 	req = usb_ep_alloc_request(ep, 0);
509 	if (!req)
510 		return req;
511 
512 	req->length = length;
513 	req->buf = memalign(CONFIG_SYS_CACHELINE_SIZE, length);
514 	if (!req->buf) {
515 		usb_ep_free_request(ep, req);
516 		req = NULL;
517 	}
518 
519 	return req;
520 }
521 
522 
523 static struct usb_request *sdp_start_ep(struct usb_ep *ep)
524 {
525 	struct usb_request *req;
526 
527 	req = alloc_ep_req(ep, 64);
528 	debug("%s: ep:%p req:%p\n", __func__, ep, req);
529 
530 	if (!req)
531 		return NULL;
532 
533 	memset(req->buf, 0, req->length);
534 	req->complete = sdp_tx_complete;
535 
536 	return req;
537 }
538 static int sdp_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
539 {
540 	struct f_sdp *sdp = func_to_sdp(f);
541 	struct usb_composite_dev *cdev = f->config->cdev;
542 	int result;
543 
544 	debug("%s: intf: %d alt: %d\n", __func__, intf, alt);
545 
546 	result = usb_ep_enable(sdp->in_ep, &in_desc);
547 	if (result)
548 		return result;
549 	sdp->in_req = sdp_start_ep(sdp->in_ep);
550 	sdp->in_req->context = sdp;
551 
552 	sdp->in_ep->driver_data = cdev; /* claim */
553 
554 	sdp->altsetting = alt;
555 	sdp->state = SDP_STATE_IDLE;
556 
557 	return 0;
558 }
559 
560 static int sdp_get_alt(struct usb_function *f, unsigned intf)
561 {
562 	struct f_sdp *sdp = func_to_sdp(f);
563 
564 	return sdp->altsetting;
565 }
566 
567 static void sdp_disable(struct usb_function *f)
568 {
569 	struct f_sdp *sdp = func_to_sdp(f);
570 
571 	usb_ep_disable(sdp->in_ep);
572 
573 	if (sdp->in_req) {
574 		free(sdp->in_req);
575 		sdp->in_req = NULL;
576 	}
577 }
578 
579 static int sdp_bind_config(struct usb_configuration *c)
580 {
581 	int status;
582 
583 	if (!sdp_func) {
584 		sdp_func = memalign(CONFIG_SYS_CACHELINE_SIZE, sizeof(*sdp_func));
585 		if (!sdp_func)
586 			return -ENOMEM;
587 	}
588 
589 	memset(sdp_func, 0, sizeof(*sdp_func));
590 
591 	sdp_func->usb_function.name = "sdp";
592 	sdp_func->usb_function.hs_descriptors = sdp_runtime_descs;
593 	sdp_func->usb_function.descriptors = sdp_runtime_descs;
594 	sdp_func->usb_function.bind = sdp_bind;
595 	sdp_func->usb_function.unbind = sdp_unbind;
596 	sdp_func->usb_function.set_alt = sdp_set_alt;
597 	sdp_func->usb_function.get_alt = sdp_get_alt;
598 	sdp_func->usb_function.disable = sdp_disable;
599 	sdp_func->usb_function.strings = sdp_generic_strings;
600 	sdp_func->usb_function.setup = sdp_setup;
601 
602 	status = usb_add_function(c, &sdp_func->usb_function);
603 
604 	return status;
605 }
606 
607 int sdp_init(int controller_index)
608 {
609 	printf("SDP: initialize...\n");
610 	while (!sdp_func->configuration_done) {
611 		if (ctrlc()) {
612 			puts("\rCTRL+C - Operation aborted.\n");
613 			return 1;
614 		}
615 
616 		WATCHDOG_RESET();
617 		usb_gadget_handle_interrupts(controller_index);
618 	}
619 
620 	return 0;
621 }
622 
623 static u32 sdp_jump_imxheader(void *address)
624 {
625 	flash_header_v2_t *headerv2 = address;
626 	ulong (*entry)(void);
627 
628 	if (headerv2->header.tag != IVT_HEADER_TAG) {
629 		printf("Header Tag is not an IMX image\n");
630 		return SDP_ERROR_IMXHEADER;
631 	}
632 
633 	printf("Jumping to 0x%08x\n", headerv2->entry);
634 	entry = sdp_ptr(headerv2->entry);
635 	entry();
636 
637 	/* The image probably never returns hence we won't reach that point */
638 	return 0;
639 }
640 
641 static void sdp_handle_in_ep(void)
642 {
643 	u8 *data = sdp_func->in_req->buf;
644 	u32 status;
645 	int datalen;
646 
647 	switch (sdp_func->state) {
648 	case SDP_STATE_TX_SEC_CONF:
649 		debug("Report 3: HAB security\n");
650 		data[0] = 3;
651 
652 		status = SDP_SECURITY_OPEN;
653 		memcpy(&data[1], &status, 4);
654 		sdp_func->in_req->length = 5;
655 		usb_ep_queue(sdp_func->in_ep, sdp_func->in_req, 0);
656 		sdp_func->state = SDP_STATE_TX_SEC_CONF_BUSY;
657 		break;
658 
659 	case SDP_STATE_TX_STATUS:
660 		debug("Report 4: Status\n");
661 		data[0] = 4;
662 
663 		memcpy(&data[1], &sdp_func->error_status, 4);
664 		sdp_func->in_req->length = 65;
665 		usb_ep_queue(sdp_func->in_ep, sdp_func->in_req, 0);
666 		sdp_func->state = SDP_STATE_TX_STATUS_BUSY;
667 		break;
668 	case SDP_STATE_TX_REGISTER:
669 		debug("Report 4: Register Values\n");
670 		data[0] = 4;
671 
672 		datalen = sdp_func->dnl_bytes_remaining;
673 
674 		if (datalen > 64)
675 			datalen = 64;
676 
677 		memcpy(&data[1], sdp_ptr(sdp_func->dnl_address), datalen);
678 		sdp_func->in_req->length = 65;
679 
680 		sdp_func->dnl_bytes_remaining -= datalen;
681 		sdp_func->dnl_address += datalen;
682 
683 		usb_ep_queue(sdp_func->in_ep, sdp_func->in_req, 0);
684 		sdp_func->state = SDP_STATE_TX_REGISTER_BUSY;
685 		break;
686 	case SDP_STATE_JUMP:
687 		printf("Jumping to header at 0x%08x\n", sdp_func->jmp_address);
688 		status = sdp_jump_imxheader(sdp_ptr(sdp_func->jmp_address));
689 
690 		/* If imx header fails, try some U-Boot specific headers */
691 		if (status) {
692 #ifdef CONFIG_SPL_BUILD
693 			/* In SPL, allow jumps to U-Boot images */
694 			struct spl_image_info spl_image = {};
695 			spl_parse_image_header(&spl_image,
696 				(struct image_header *)sdp_func->jmp_address);
697 			jump_to_image_no_args(&spl_image);
698 #else
699 			/* In U-Boot, allow jumps to scripts */
700 			source(sdp_func->jmp_address, "script@1");
701 #endif
702 		}
703 
704 		sdp_func->next_state = SDP_STATE_IDLE;
705 		sdp_func->error_status = status;
706 
707 		/* Only send Report 4 if there was an error */
708 		if (status)
709 			sdp_func->state = SDP_STATE_TX_STATUS;
710 		else
711 			sdp_func->state = SDP_STATE_IDLE;
712 		break;
713 	default:
714 		break;
715 	};
716 }
717 
718 void sdp_handle(int controller_index)
719 {
720 	printf("SDP: handle requests...\n");
721 	while (1) {
722 		if (ctrlc()) {
723 			puts("\rCTRL+C - Operation aborted.\n");
724 			return;
725 		}
726 
727 		WATCHDOG_RESET();
728 		usb_gadget_handle_interrupts(controller_index);
729 
730 		sdp_handle_in_ep();
731 	}
732 }
733 
734 int sdp_add(struct usb_configuration *c)
735 {
736 	int id;
737 
738 	id = usb_string_id(c->cdev);
739 	if (id < 0)
740 		return id;
741 	strings_sdp_generic[0].id = id;
742 	sdp_intf_runtime.iInterface = id;
743 
744 	debug("%s: cdev: %p gadget: %p gadget->ep0: %p\n", __func__,
745 	      c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
746 
747 	return sdp_bind_config(c);
748 }
749 
750 DECLARE_GADGET_BIND_CALLBACK(usb_dnl_sdp, sdp_add);
751