xref: /linux/drivers/greybus/es2.c (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Greybus "AP" USB driver for "ES2" controller chips
4  *
5  * Copyright 2014-2015 Google Inc.
6  * Copyright 2014-2015 Linaro Ltd.
7  */
8 #include <linux/kthread.h>
9 #include <linux/sizes.h>
10 #include <linux/usb.h>
11 #include <linux/kfifo.h>
12 #include <linux/debugfs.h>
13 #include <linux/list.h>
14 #include <linux/greybus.h>
15 #include <asm/unaligned.h>
16 
17 #include "arpc.h"
18 #include "greybus_trace.h"
19 
20 
21 /* Default timeout for USB vendor requests. */
22 #define ES2_USB_CTRL_TIMEOUT	500
23 
24 /* Default timeout for ARPC CPort requests */
25 #define ES2_ARPC_CPORT_TIMEOUT	500
26 
27 /* Fixed CPort numbers */
28 #define ES2_CPORT_CDSI0		16
29 #define ES2_CPORT_CDSI1		17
30 
31 /* Memory sizes for the buffers sent to/from the ES2 controller */
32 #define ES2_GBUF_MSG_SIZE_MAX	2048
33 
34 /* Memory sizes for the ARPC buffers */
35 #define ARPC_OUT_SIZE_MAX	U16_MAX
36 #define ARPC_IN_SIZE_MAX	128
37 
38 static const struct usb_device_id id_table[] = {
39 	{ USB_DEVICE(0x18d1, 0x1eaf) },
40 	{ },
41 };
42 MODULE_DEVICE_TABLE(usb, id_table);
43 
44 #define APB1_LOG_SIZE		SZ_16K
45 
46 /*
47  * Number of CPort IN urbs in flight at any point in time.
48  * Adjust if we are having stalls in the USB buffer due to not enough urbs in
49  * flight.
50  */
51 #define NUM_CPORT_IN_URB	4
52 
53 /* Number of CPort OUT urbs in flight at any point in time.
54  * Adjust if we get messages saying we are out of urbs in the system log.
55  */
56 #define NUM_CPORT_OUT_URB	8
57 
58 /*
59  * Number of ARPC in urbs in flight at any point in time.
60  */
61 #define NUM_ARPC_IN_URB		2
62 
63 /*
64  * @endpoint: bulk in endpoint for CPort data
65  * @urb: array of urbs for the CPort in messages
66  * @buffer: array of buffers for the @cport_in_urb urbs
67  */
68 struct es2_cport_in {
69 	__u8 endpoint;
70 	struct urb *urb[NUM_CPORT_IN_URB];
71 	u8 *buffer[NUM_CPORT_IN_URB];
72 };
73 
74 /**
75  * struct es2_ap_dev - ES2 USB Bridge to AP structure
76  * @usb_dev: pointer to the USB device we are.
77  * @usb_intf: pointer to the USB interface we are bound to.
78  * @hd: pointer to our gb_host_device structure
79  *
80  * @cport_in: endpoint, urbs and buffer for cport in messages
81  * @cport_out_endpoint: endpoint for cport out messages
82  * @cport_out_urb: array of urbs for the CPort out messages
83  * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or
84  *			not.
85  * @cport_out_urb_cancelled: array of flags indicating whether the
86  *			corresponding @cport_out_urb is being cancelled
87  * @cport_out_urb_lock: locks the @cport_out_urb_busy "list"
88  * @cdsi1_in_use: true if cport CDSI1 is in use
89  * @apb_log_task: task pointer for logging thread
90  * @apb_log_dentry: file system entry for the log file interface
91  * @apb_log_enable_dentry: file system entry for enabling logging
92  * @apb_log_fifo: kernel FIFO to carry logged data
93  * @arpc_urb: array of urbs for the ARPC in messages
94  * @arpc_buffer: array of buffers for the @arpc_urb urbs
95  * @arpc_endpoint_in: bulk in endpoint for APBridgeA RPC
96  * @arpc_id_cycle: gives an unique id to ARPC
97  * @arpc_lock: locks ARPC list
98  * @arpcs: list of in progress ARPCs
99  */
100 struct es2_ap_dev {
101 	struct usb_device *usb_dev;
102 	struct usb_interface *usb_intf;
103 	struct gb_host_device *hd;
104 
105 	struct es2_cport_in cport_in;
106 	__u8 cport_out_endpoint;
107 	struct urb *cport_out_urb[NUM_CPORT_OUT_URB];
108 	bool cport_out_urb_busy[NUM_CPORT_OUT_URB];
109 	bool cport_out_urb_cancelled[NUM_CPORT_OUT_URB];
110 	spinlock_t cport_out_urb_lock;
111 
112 	bool cdsi1_in_use;
113 
114 	struct task_struct *apb_log_task;
115 	struct dentry *apb_log_dentry;
116 	struct dentry *apb_log_enable_dentry;
117 	DECLARE_KFIFO(apb_log_fifo, char, APB1_LOG_SIZE);
118 
119 	__u8 arpc_endpoint_in;
120 	struct urb *arpc_urb[NUM_ARPC_IN_URB];
121 	u8 *arpc_buffer[NUM_ARPC_IN_URB];
122 
123 	int arpc_id_cycle;
124 	spinlock_t arpc_lock;
125 	struct list_head arpcs;
126 };
127 
128 struct arpc {
129 	struct list_head list;
130 	struct arpc_request_message *req;
131 	struct arpc_response_message *resp;
132 	struct completion response_received;
133 	bool active;
134 };
135 
136 static inline struct es2_ap_dev *hd_to_es2(struct gb_host_device *hd)
137 {
138 	return (struct es2_ap_dev *)&hd->hd_priv;
139 }
140 
141 static void cport_out_callback(struct urb *urb);
142 static void usb_log_enable(struct es2_ap_dev *es2);
143 static void usb_log_disable(struct es2_ap_dev *es2);
144 static int arpc_sync(struct es2_ap_dev *es2, u8 type, void *payload,
145 		     size_t size, int *result, unsigned int timeout);
146 
147 static int output_sync(struct es2_ap_dev *es2, void *req, u16 size, u8 cmd)
148 {
149 	struct usb_device *udev = es2->usb_dev;
150 	u8 *data;
151 	int retval;
152 
153 	data = kmemdup(req, size, GFP_KERNEL);
154 	if (!data)
155 		return -ENOMEM;
156 
157 	retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
158 				 cmd,
159 				 USB_DIR_OUT | USB_TYPE_VENDOR |
160 				 USB_RECIP_INTERFACE,
161 				 0, 0, data, size, ES2_USB_CTRL_TIMEOUT);
162 	if (retval < 0)
163 		dev_err(&udev->dev, "%s: return error %d\n", __func__, retval);
164 	else
165 		retval = 0;
166 
167 	kfree(data);
168 	return retval;
169 }
170 
171 static void ap_urb_complete(struct urb *urb)
172 {
173 	struct usb_ctrlrequest *dr = urb->context;
174 
175 	kfree(dr);
176 	usb_free_urb(urb);
177 }
178 
179 static int output_async(struct es2_ap_dev *es2, void *req, u16 size, u8 cmd)
180 {
181 	struct usb_device *udev = es2->usb_dev;
182 	struct urb *urb;
183 	struct usb_ctrlrequest *dr;
184 	u8 *buf;
185 	int retval;
186 
187 	urb = usb_alloc_urb(0, GFP_ATOMIC);
188 	if (!urb)
189 		return -ENOMEM;
190 
191 	dr = kmalloc(sizeof(*dr) + size, GFP_ATOMIC);
192 	if (!dr) {
193 		usb_free_urb(urb);
194 		return -ENOMEM;
195 	}
196 
197 	buf = (u8 *)dr + sizeof(*dr);
198 	memcpy(buf, req, size);
199 
200 	dr->bRequest = cmd;
201 	dr->bRequestType = USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE;
202 	dr->wValue = 0;
203 	dr->wIndex = 0;
204 	dr->wLength = cpu_to_le16(size);
205 
206 	usb_fill_control_urb(urb, udev, usb_sndctrlpipe(udev, 0),
207 			     (unsigned char *)dr, buf, size,
208 			     ap_urb_complete, dr);
209 	retval = usb_submit_urb(urb, GFP_ATOMIC);
210 	if (retval) {
211 		usb_free_urb(urb);
212 		kfree(dr);
213 	}
214 	return retval;
215 }
216 
217 static int output(struct gb_host_device *hd, void *req, u16 size, u8 cmd,
218 		  bool async)
219 {
220 	struct es2_ap_dev *es2 = hd_to_es2(hd);
221 
222 	if (async)
223 		return output_async(es2, req, size, cmd);
224 
225 	return output_sync(es2, req, size, cmd);
226 }
227 
228 static int es2_cport_in_enable(struct es2_ap_dev *es2,
229 			       struct es2_cport_in *cport_in)
230 {
231 	struct urb *urb;
232 	int ret;
233 	int i;
234 
235 	for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
236 		urb = cport_in->urb[i];
237 
238 		ret = usb_submit_urb(urb, GFP_KERNEL);
239 		if (ret) {
240 			dev_err(&es2->usb_dev->dev,
241 				"failed to submit in-urb: %d\n", ret);
242 			goto err_kill_urbs;
243 		}
244 	}
245 
246 	return 0;
247 
248 err_kill_urbs:
249 	for (--i; i >= 0; --i) {
250 		urb = cport_in->urb[i];
251 		usb_kill_urb(urb);
252 	}
253 
254 	return ret;
255 }
256 
257 static void es2_cport_in_disable(struct es2_ap_dev *es2,
258 				 struct es2_cport_in *cport_in)
259 {
260 	struct urb *urb;
261 	int i;
262 
263 	for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
264 		urb = cport_in->urb[i];
265 		usb_kill_urb(urb);
266 	}
267 }
268 
269 static int es2_arpc_in_enable(struct es2_ap_dev *es2)
270 {
271 	struct urb *urb;
272 	int ret;
273 	int i;
274 
275 	for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
276 		urb = es2->arpc_urb[i];
277 
278 		ret = usb_submit_urb(urb, GFP_KERNEL);
279 		if (ret) {
280 			dev_err(&es2->usb_dev->dev,
281 				"failed to submit arpc in-urb: %d\n", ret);
282 			goto err_kill_urbs;
283 		}
284 	}
285 
286 	return 0;
287 
288 err_kill_urbs:
289 	for (--i; i >= 0; --i) {
290 		urb = es2->arpc_urb[i];
291 		usb_kill_urb(urb);
292 	}
293 
294 	return ret;
295 }
296 
297 static void es2_arpc_in_disable(struct es2_ap_dev *es2)
298 {
299 	struct urb *urb;
300 	int i;
301 
302 	for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
303 		urb = es2->arpc_urb[i];
304 		usb_kill_urb(urb);
305 	}
306 }
307 
308 static struct urb *next_free_urb(struct es2_ap_dev *es2, gfp_t gfp_mask)
309 {
310 	struct urb *urb = NULL;
311 	unsigned long flags;
312 	int i;
313 
314 	spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
315 
316 	/* Look in our pool of allocated urbs first, as that's the "fastest" */
317 	for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
318 		if (!es2->cport_out_urb_busy[i] &&
319 		    !es2->cport_out_urb_cancelled[i]) {
320 			es2->cport_out_urb_busy[i] = true;
321 			urb = es2->cport_out_urb[i];
322 			break;
323 		}
324 	}
325 	spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
326 	if (urb)
327 		return urb;
328 
329 	/*
330 	 * Crap, pool is empty, complain to the syslog and go allocate one
331 	 * dynamically as we have to succeed.
332 	 */
333 	dev_dbg(&es2->usb_dev->dev,
334 		"No free CPort OUT urbs, having to dynamically allocate one!\n");
335 	return usb_alloc_urb(0, gfp_mask);
336 }
337 
338 static void free_urb(struct es2_ap_dev *es2, struct urb *urb)
339 {
340 	unsigned long flags;
341 	int i;
342 	/*
343 	 * See if this was an urb in our pool, if so mark it "free", otherwise
344 	 * we need to free it ourselves.
345 	 */
346 	spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
347 	for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
348 		if (urb == es2->cport_out_urb[i]) {
349 			es2->cport_out_urb_busy[i] = false;
350 			urb = NULL;
351 			break;
352 		}
353 	}
354 	spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
355 
356 	/* If urb is not NULL, then we need to free this urb */
357 	usb_free_urb(urb);
358 }
359 
360 /*
361  * We (ab)use the operation-message header pad bytes to transfer the
362  * cport id in order to minimise overhead.
363  */
364 static void
365 gb_message_cport_pack(struct gb_operation_msg_hdr *header, u16 cport_id)
366 {
367 	header->pad[0] = cport_id;
368 }
369 
370 /* Clear the pad bytes used for the CPort id */
371 static void gb_message_cport_clear(struct gb_operation_msg_hdr *header)
372 {
373 	header->pad[0] = 0;
374 }
375 
376 /* Extract the CPort id packed into the header, and clear it */
377 static u16 gb_message_cport_unpack(struct gb_operation_msg_hdr *header)
378 {
379 	u16 cport_id = header->pad[0];
380 
381 	gb_message_cport_clear(header);
382 
383 	return cport_id;
384 }
385 
386 /*
387  * Returns zero if the message was successfully queued, or a negative errno
388  * otherwise.
389  */
390 static int message_send(struct gb_host_device *hd, u16 cport_id,
391 			struct gb_message *message, gfp_t gfp_mask)
392 {
393 	struct es2_ap_dev *es2 = hd_to_es2(hd);
394 	struct usb_device *udev = es2->usb_dev;
395 	size_t buffer_size;
396 	int retval;
397 	struct urb *urb;
398 	unsigned long flags;
399 
400 	/*
401 	 * The data actually transferred will include an indication
402 	 * of where the data should be sent.  Do one last check of
403 	 * the target CPort id before filling it in.
404 	 */
405 	if (!cport_id_valid(hd, cport_id)) {
406 		dev_err(&udev->dev, "invalid cport %u\n", cport_id);
407 		return -EINVAL;
408 	}
409 
410 	/* Find a free urb */
411 	urb = next_free_urb(es2, gfp_mask);
412 	if (!urb)
413 		return -ENOMEM;
414 
415 	spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
416 	message->hcpriv = urb;
417 	spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
418 
419 	/* Pack the cport id into the message header */
420 	gb_message_cport_pack(message->header, cport_id);
421 
422 	buffer_size = sizeof(*message->header) + message->payload_size;
423 
424 	usb_fill_bulk_urb(urb, udev,
425 			  usb_sndbulkpipe(udev,
426 					  es2->cport_out_endpoint),
427 			  message->buffer, buffer_size,
428 			  cport_out_callback, message);
429 	urb->transfer_flags |= URB_ZERO_PACKET;
430 
431 	trace_gb_message_submit(message);
432 
433 	retval = usb_submit_urb(urb, gfp_mask);
434 	if (retval) {
435 		dev_err(&udev->dev, "failed to submit out-urb: %d\n", retval);
436 
437 		spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
438 		message->hcpriv = NULL;
439 		spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
440 
441 		free_urb(es2, urb);
442 		gb_message_cport_clear(message->header);
443 
444 		return retval;
445 	}
446 
447 	return 0;
448 }
449 
450 /*
451  * Can not be called in atomic context.
452  */
453 static void message_cancel(struct gb_message *message)
454 {
455 	struct gb_host_device *hd = message->operation->connection->hd;
456 	struct es2_ap_dev *es2 = hd_to_es2(hd);
457 	struct urb *urb;
458 	int i;
459 
460 	might_sleep();
461 
462 	spin_lock_irq(&es2->cport_out_urb_lock);
463 	urb = message->hcpriv;
464 
465 	/* Prevent dynamically allocated urb from being deallocated. */
466 	usb_get_urb(urb);
467 
468 	/* Prevent pre-allocated urb from being reused. */
469 	for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
470 		if (urb == es2->cport_out_urb[i]) {
471 			es2->cport_out_urb_cancelled[i] = true;
472 			break;
473 		}
474 	}
475 	spin_unlock_irq(&es2->cport_out_urb_lock);
476 
477 	usb_kill_urb(urb);
478 
479 	if (i < NUM_CPORT_OUT_URB) {
480 		spin_lock_irq(&es2->cport_out_urb_lock);
481 		es2->cport_out_urb_cancelled[i] = false;
482 		spin_unlock_irq(&es2->cport_out_urb_lock);
483 	}
484 
485 	usb_free_urb(urb);
486 }
487 
488 static int es2_cport_allocate(struct gb_host_device *hd, int cport_id,
489 			      unsigned long flags)
490 {
491 	struct es2_ap_dev *es2 = hd_to_es2(hd);
492 	struct ida *id_map = &hd->cport_id_map;
493 	int ida_start, ida_end;
494 
495 	switch (cport_id) {
496 	case ES2_CPORT_CDSI0:
497 	case ES2_CPORT_CDSI1:
498 		dev_err(&hd->dev, "cport %d not available\n", cport_id);
499 		return -EBUSY;
500 	}
501 
502 	if (flags & GB_CONNECTION_FLAG_OFFLOADED &&
503 	    flags & GB_CONNECTION_FLAG_CDSI1) {
504 		if (es2->cdsi1_in_use) {
505 			dev_err(&hd->dev, "CDSI1 already in use\n");
506 			return -EBUSY;
507 		}
508 
509 		es2->cdsi1_in_use = true;
510 
511 		return ES2_CPORT_CDSI1;
512 	}
513 
514 	if (cport_id < 0) {
515 		ida_start = 0;
516 		ida_end = hd->num_cports - 1;
517 	} else if (cport_id < hd->num_cports) {
518 		ida_start = cport_id;
519 		ida_end = cport_id;
520 	} else {
521 		dev_err(&hd->dev, "cport %d not available\n", cport_id);
522 		return -EINVAL;
523 	}
524 
525 	return ida_alloc_range(id_map, ida_start, ida_end, GFP_KERNEL);
526 }
527 
528 static void es2_cport_release(struct gb_host_device *hd, u16 cport_id)
529 {
530 	struct es2_ap_dev *es2 = hd_to_es2(hd);
531 
532 	switch (cport_id) {
533 	case ES2_CPORT_CDSI1:
534 		es2->cdsi1_in_use = false;
535 		return;
536 	}
537 
538 	ida_free(&hd->cport_id_map, cport_id);
539 }
540 
541 static int cport_enable(struct gb_host_device *hd, u16 cport_id,
542 			unsigned long flags)
543 {
544 	struct es2_ap_dev *es2 = hd_to_es2(hd);
545 	struct usb_device *udev = es2->usb_dev;
546 	struct gb_apb_request_cport_flags *req;
547 	u32 connection_flags;
548 	int ret;
549 
550 	req = kzalloc(sizeof(*req), GFP_KERNEL);
551 	if (!req)
552 		return -ENOMEM;
553 
554 	connection_flags = 0;
555 	if (flags & GB_CONNECTION_FLAG_CONTROL)
556 		connection_flags |= GB_APB_CPORT_FLAG_CONTROL;
557 	if (flags & GB_CONNECTION_FLAG_HIGH_PRIO)
558 		connection_flags |= GB_APB_CPORT_FLAG_HIGH_PRIO;
559 
560 	req->flags = cpu_to_le32(connection_flags);
561 
562 	dev_dbg(&hd->dev, "%s - cport = %u, flags = %02x\n", __func__,
563 		cport_id, connection_flags);
564 
565 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
566 			      GB_APB_REQUEST_CPORT_FLAGS,
567 			      USB_DIR_OUT | USB_TYPE_VENDOR |
568 			      USB_RECIP_INTERFACE, cport_id, 0,
569 			      req, sizeof(*req), ES2_USB_CTRL_TIMEOUT);
570 	if (ret < 0) {
571 		dev_err(&udev->dev, "failed to set cport flags for port %d\n",
572 			cport_id);
573 		goto out;
574 	}
575 
576 	ret = 0;
577 out:
578 	kfree(req);
579 
580 	return ret;
581 }
582 
583 static int es2_cport_connected(struct gb_host_device *hd, u16 cport_id)
584 {
585 	struct es2_ap_dev *es2 = hd_to_es2(hd);
586 	struct device *dev = &es2->usb_dev->dev;
587 	struct arpc_cport_connected_req req;
588 	int ret;
589 
590 	req.cport_id = cpu_to_le16(cport_id);
591 	ret = arpc_sync(es2, ARPC_TYPE_CPORT_CONNECTED, &req, sizeof(req),
592 			NULL, ES2_ARPC_CPORT_TIMEOUT);
593 	if (ret) {
594 		dev_err(dev, "failed to set connected state for cport %u: %d\n",
595 			cport_id, ret);
596 		return ret;
597 	}
598 
599 	return 0;
600 }
601 
602 static int es2_cport_flush(struct gb_host_device *hd, u16 cport_id)
603 {
604 	struct es2_ap_dev *es2 = hd_to_es2(hd);
605 	struct device *dev = &es2->usb_dev->dev;
606 	struct arpc_cport_flush_req req;
607 	int ret;
608 
609 	req.cport_id = cpu_to_le16(cport_id);
610 	ret = arpc_sync(es2, ARPC_TYPE_CPORT_FLUSH, &req, sizeof(req),
611 			NULL, ES2_ARPC_CPORT_TIMEOUT);
612 	if (ret) {
613 		dev_err(dev, "failed to flush cport %u: %d\n", cport_id, ret);
614 		return ret;
615 	}
616 
617 	return 0;
618 }
619 
620 static int es2_cport_shutdown(struct gb_host_device *hd, u16 cport_id,
621 			      u8 phase, unsigned int timeout)
622 {
623 	struct es2_ap_dev *es2 = hd_to_es2(hd);
624 	struct device *dev = &es2->usb_dev->dev;
625 	struct arpc_cport_shutdown_req req;
626 	int result;
627 	int ret;
628 
629 	if (timeout > U16_MAX)
630 		return -EINVAL;
631 
632 	req.cport_id = cpu_to_le16(cport_id);
633 	req.timeout = cpu_to_le16(timeout);
634 	req.phase = phase;
635 	ret = arpc_sync(es2, ARPC_TYPE_CPORT_SHUTDOWN, &req, sizeof(req),
636 			&result, ES2_ARPC_CPORT_TIMEOUT + timeout);
637 	if (ret) {
638 		dev_err(dev, "failed to send shutdown over cport %u: %d (%d)\n",
639 			cport_id, ret, result);
640 		return ret;
641 	}
642 
643 	return 0;
644 }
645 
646 static int es2_cport_quiesce(struct gb_host_device *hd, u16 cport_id,
647 			     size_t peer_space, unsigned int timeout)
648 {
649 	struct es2_ap_dev *es2 = hd_to_es2(hd);
650 	struct device *dev = &es2->usb_dev->dev;
651 	struct arpc_cport_quiesce_req req;
652 	int result;
653 	int ret;
654 
655 	if (peer_space > U16_MAX)
656 		return -EINVAL;
657 
658 	if (timeout > U16_MAX)
659 		return -EINVAL;
660 
661 	req.cport_id = cpu_to_le16(cport_id);
662 	req.peer_space = cpu_to_le16(peer_space);
663 	req.timeout = cpu_to_le16(timeout);
664 	ret = arpc_sync(es2, ARPC_TYPE_CPORT_QUIESCE, &req, sizeof(req),
665 			&result, ES2_ARPC_CPORT_TIMEOUT + timeout);
666 	if (ret) {
667 		dev_err(dev, "failed to quiesce cport %u: %d (%d)\n",
668 			cport_id, ret, result);
669 		return ret;
670 	}
671 
672 	return 0;
673 }
674 
675 static int es2_cport_clear(struct gb_host_device *hd, u16 cport_id)
676 {
677 	struct es2_ap_dev *es2 = hd_to_es2(hd);
678 	struct device *dev = &es2->usb_dev->dev;
679 	struct arpc_cport_clear_req req;
680 	int ret;
681 
682 	req.cport_id = cpu_to_le16(cport_id);
683 	ret = arpc_sync(es2, ARPC_TYPE_CPORT_CLEAR, &req, sizeof(req),
684 			NULL, ES2_ARPC_CPORT_TIMEOUT);
685 	if (ret) {
686 		dev_err(dev, "failed to clear cport %u: %d\n", cport_id, ret);
687 		return ret;
688 	}
689 
690 	return 0;
691 }
692 
693 static int latency_tag_enable(struct gb_host_device *hd, u16 cport_id)
694 {
695 	int retval;
696 	struct es2_ap_dev *es2 = hd_to_es2(hd);
697 	struct usb_device *udev = es2->usb_dev;
698 
699 	retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
700 				 GB_APB_REQUEST_LATENCY_TAG_EN,
701 				 USB_DIR_OUT | USB_TYPE_VENDOR |
702 				 USB_RECIP_INTERFACE, cport_id, 0, NULL,
703 				 0, ES2_USB_CTRL_TIMEOUT);
704 
705 	if (retval < 0)
706 		dev_err(&udev->dev, "Cannot enable latency tag for cport %d\n",
707 			cport_id);
708 	return retval;
709 }
710 
711 static int latency_tag_disable(struct gb_host_device *hd, u16 cport_id)
712 {
713 	int retval;
714 	struct es2_ap_dev *es2 = hd_to_es2(hd);
715 	struct usb_device *udev = es2->usb_dev;
716 
717 	retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
718 				 GB_APB_REQUEST_LATENCY_TAG_DIS,
719 				 USB_DIR_OUT | USB_TYPE_VENDOR |
720 				 USB_RECIP_INTERFACE, cport_id, 0, NULL,
721 				 0, ES2_USB_CTRL_TIMEOUT);
722 
723 	if (retval < 0)
724 		dev_err(&udev->dev, "Cannot disable latency tag for cport %d\n",
725 			cport_id);
726 	return retval;
727 }
728 
729 static struct gb_hd_driver es2_driver = {
730 	.hd_priv_size			= sizeof(struct es2_ap_dev),
731 	.message_send			= message_send,
732 	.message_cancel			= message_cancel,
733 	.cport_allocate			= es2_cport_allocate,
734 	.cport_release			= es2_cport_release,
735 	.cport_enable			= cport_enable,
736 	.cport_connected		= es2_cport_connected,
737 	.cport_flush			= es2_cport_flush,
738 	.cport_shutdown			= es2_cport_shutdown,
739 	.cport_quiesce			= es2_cport_quiesce,
740 	.cport_clear			= es2_cport_clear,
741 	.latency_tag_enable		= latency_tag_enable,
742 	.latency_tag_disable		= latency_tag_disable,
743 	.output				= output,
744 };
745 
746 /* Common function to report consistent warnings based on URB status */
747 static int check_urb_status(struct urb *urb)
748 {
749 	struct device *dev = &urb->dev->dev;
750 	int status = urb->status;
751 
752 	switch (status) {
753 	case 0:
754 		return 0;
755 
756 	case -EOVERFLOW:
757 		dev_err(dev, "%s: overflow actual length is %d\n",
758 			__func__, urb->actual_length);
759 		fallthrough;
760 	case -ECONNRESET:
761 	case -ENOENT:
762 	case -ESHUTDOWN:
763 	case -EILSEQ:
764 	case -EPROTO:
765 		/* device is gone, stop sending */
766 		return status;
767 	}
768 	dev_err(dev, "%s: unknown status %d\n", __func__, status);
769 
770 	return -EAGAIN;
771 }
772 
773 static void es2_destroy(struct es2_ap_dev *es2)
774 {
775 	struct usb_device *udev;
776 	struct urb *urb;
777 	int i;
778 
779 	debugfs_remove(es2->apb_log_enable_dentry);
780 	usb_log_disable(es2);
781 
782 	/* Tear down everything! */
783 	for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
784 		urb = es2->cport_out_urb[i];
785 		usb_kill_urb(urb);
786 		usb_free_urb(urb);
787 		es2->cport_out_urb[i] = NULL;
788 		es2->cport_out_urb_busy[i] = false;	/* just to be anal */
789 	}
790 
791 	for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
792 		usb_free_urb(es2->arpc_urb[i]);
793 		kfree(es2->arpc_buffer[i]);
794 		es2->arpc_buffer[i] = NULL;
795 	}
796 
797 	for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
798 		usb_free_urb(es2->cport_in.urb[i]);
799 		kfree(es2->cport_in.buffer[i]);
800 		es2->cport_in.buffer[i] = NULL;
801 	}
802 
803 	/* release reserved CDSI0 and CDSI1 cports */
804 	gb_hd_cport_release_reserved(es2->hd, ES2_CPORT_CDSI1);
805 	gb_hd_cport_release_reserved(es2->hd, ES2_CPORT_CDSI0);
806 
807 	udev = es2->usb_dev;
808 	gb_hd_put(es2->hd);
809 
810 	usb_put_dev(udev);
811 }
812 
813 static void cport_in_callback(struct urb *urb)
814 {
815 	struct gb_host_device *hd = urb->context;
816 	struct device *dev = &urb->dev->dev;
817 	struct gb_operation_msg_hdr *header;
818 	int status = check_urb_status(urb);
819 	int retval;
820 	u16 cport_id;
821 
822 	if (status) {
823 		if ((status == -EAGAIN) || (status == -EPROTO))
824 			goto exit;
825 
826 		/* The urb is being unlinked */
827 		if (status == -ENOENT || status == -ESHUTDOWN)
828 			return;
829 
830 		dev_err(dev, "urb cport in error %d (dropped)\n", status);
831 		return;
832 	}
833 
834 	if (urb->actual_length < sizeof(*header)) {
835 		dev_err(dev, "short message received\n");
836 		goto exit;
837 	}
838 
839 	/* Extract the CPort id, which is packed in the message header */
840 	header = urb->transfer_buffer;
841 	cport_id = gb_message_cport_unpack(header);
842 
843 	if (cport_id_valid(hd, cport_id)) {
844 		greybus_data_rcvd(hd, cport_id, urb->transfer_buffer,
845 				  urb->actual_length);
846 	} else {
847 		dev_err(dev, "invalid cport id %u received\n", cport_id);
848 	}
849 exit:
850 	/* put our urb back in the request pool */
851 	retval = usb_submit_urb(urb, GFP_ATOMIC);
852 	if (retval)
853 		dev_err(dev, "failed to resubmit in-urb: %d\n", retval);
854 }
855 
856 static void cport_out_callback(struct urb *urb)
857 {
858 	struct gb_message *message = urb->context;
859 	struct gb_host_device *hd = message->operation->connection->hd;
860 	struct es2_ap_dev *es2 = hd_to_es2(hd);
861 	int status = check_urb_status(urb);
862 	unsigned long flags;
863 
864 	gb_message_cport_clear(message->header);
865 
866 	spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
867 	message->hcpriv = NULL;
868 	spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
869 
870 	/*
871 	 * Tell the submitter that the message send (attempt) is
872 	 * complete, and report the status.
873 	 */
874 	greybus_message_sent(hd, message, status);
875 
876 	free_urb(es2, urb);
877 }
878 
879 static struct arpc *arpc_alloc(void *payload, u16 size, u8 type)
880 {
881 	struct arpc *rpc;
882 
883 	if (size + sizeof(*rpc->req) > ARPC_OUT_SIZE_MAX)
884 		return NULL;
885 
886 	rpc = kzalloc(sizeof(*rpc), GFP_KERNEL);
887 	if (!rpc)
888 		return NULL;
889 
890 	INIT_LIST_HEAD(&rpc->list);
891 	rpc->req = kzalloc(sizeof(*rpc->req) + size, GFP_KERNEL);
892 	if (!rpc->req)
893 		goto err_free_rpc;
894 
895 	rpc->resp = kzalloc(sizeof(*rpc->resp), GFP_KERNEL);
896 	if (!rpc->resp)
897 		goto err_free_req;
898 
899 	rpc->req->type = type;
900 	rpc->req->size = cpu_to_le16(sizeof(*rpc->req) + size);
901 	memcpy(rpc->req->data, payload, size);
902 
903 	init_completion(&rpc->response_received);
904 
905 	return rpc;
906 
907 err_free_req:
908 	kfree(rpc->req);
909 err_free_rpc:
910 	kfree(rpc);
911 
912 	return NULL;
913 }
914 
915 static void arpc_free(struct arpc *rpc)
916 {
917 	kfree(rpc->req);
918 	kfree(rpc->resp);
919 	kfree(rpc);
920 }
921 
922 static struct arpc *arpc_find(struct es2_ap_dev *es2, __le16 id)
923 {
924 	struct arpc *rpc;
925 
926 	list_for_each_entry(rpc, &es2->arpcs, list) {
927 		if (rpc->req->id == id)
928 			return rpc;
929 	}
930 
931 	return NULL;
932 }
933 
934 static void arpc_add(struct es2_ap_dev *es2, struct arpc *rpc)
935 {
936 	rpc->active = true;
937 	rpc->req->id = cpu_to_le16(es2->arpc_id_cycle++);
938 	list_add_tail(&rpc->list, &es2->arpcs);
939 }
940 
941 static void arpc_del(struct es2_ap_dev *es2, struct arpc *rpc)
942 {
943 	if (rpc->active) {
944 		rpc->active = false;
945 		list_del(&rpc->list);
946 	}
947 }
948 
949 static int arpc_send(struct es2_ap_dev *es2, struct arpc *rpc, int timeout)
950 {
951 	struct usb_device *udev = es2->usb_dev;
952 	int retval;
953 
954 	retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
955 				 GB_APB_REQUEST_ARPC_RUN,
956 				 USB_DIR_OUT | USB_TYPE_VENDOR |
957 				 USB_RECIP_INTERFACE,
958 				 0, 0,
959 				 rpc->req, le16_to_cpu(rpc->req->size),
960 				 ES2_USB_CTRL_TIMEOUT);
961 	if (retval < 0) {
962 		dev_err(&udev->dev,
963 			"failed to send ARPC request %d: %d\n",
964 			rpc->req->type, retval);
965 		return retval;
966 	}
967 
968 	return 0;
969 }
970 
971 static int arpc_sync(struct es2_ap_dev *es2, u8 type, void *payload,
972 		     size_t size, int *result, unsigned int timeout)
973 {
974 	struct arpc *rpc;
975 	unsigned long flags;
976 	int retval;
977 
978 	if (result)
979 		*result = 0;
980 
981 	rpc = arpc_alloc(payload, size, type);
982 	if (!rpc)
983 		return -ENOMEM;
984 
985 	spin_lock_irqsave(&es2->arpc_lock, flags);
986 	arpc_add(es2, rpc);
987 	spin_unlock_irqrestore(&es2->arpc_lock, flags);
988 
989 	retval = arpc_send(es2, rpc, timeout);
990 	if (retval)
991 		goto out_arpc_del;
992 
993 	retval = wait_for_completion_interruptible_timeout(
994 						&rpc->response_received,
995 						msecs_to_jiffies(timeout));
996 	if (retval <= 0) {
997 		if (!retval)
998 			retval = -ETIMEDOUT;
999 		goto out_arpc_del;
1000 	}
1001 
1002 	if (rpc->resp->result) {
1003 		retval = -EREMOTEIO;
1004 		if (result)
1005 			*result = rpc->resp->result;
1006 	} else {
1007 		retval = 0;
1008 	}
1009 
1010 out_arpc_del:
1011 	spin_lock_irqsave(&es2->arpc_lock, flags);
1012 	arpc_del(es2, rpc);
1013 	spin_unlock_irqrestore(&es2->arpc_lock, flags);
1014 	arpc_free(rpc);
1015 
1016 	if (retval < 0 && retval != -EREMOTEIO) {
1017 		dev_err(&es2->usb_dev->dev,
1018 			"failed to execute ARPC: %d\n", retval);
1019 	}
1020 
1021 	return retval;
1022 }
1023 
1024 static void arpc_in_callback(struct urb *urb)
1025 {
1026 	struct es2_ap_dev *es2 = urb->context;
1027 	struct device *dev = &urb->dev->dev;
1028 	int status = check_urb_status(urb);
1029 	struct arpc *rpc;
1030 	struct arpc_response_message *resp;
1031 	unsigned long flags;
1032 	int retval;
1033 
1034 	if (status) {
1035 		if ((status == -EAGAIN) || (status == -EPROTO))
1036 			goto exit;
1037 
1038 		/* The urb is being unlinked */
1039 		if (status == -ENOENT || status == -ESHUTDOWN)
1040 			return;
1041 
1042 		dev_err(dev, "arpc in-urb error %d (dropped)\n", status);
1043 		return;
1044 	}
1045 
1046 	if (urb->actual_length < sizeof(*resp)) {
1047 		dev_err(dev, "short aprc response received\n");
1048 		goto exit;
1049 	}
1050 
1051 	resp = urb->transfer_buffer;
1052 	spin_lock_irqsave(&es2->arpc_lock, flags);
1053 	rpc = arpc_find(es2, resp->id);
1054 	if (!rpc) {
1055 		dev_err(dev, "invalid arpc response id received: %u\n",
1056 			le16_to_cpu(resp->id));
1057 		spin_unlock_irqrestore(&es2->arpc_lock, flags);
1058 		goto exit;
1059 	}
1060 
1061 	arpc_del(es2, rpc);
1062 	memcpy(rpc->resp, resp, sizeof(*resp));
1063 	complete(&rpc->response_received);
1064 	spin_unlock_irqrestore(&es2->arpc_lock, flags);
1065 
1066 exit:
1067 	/* put our urb back in the request pool */
1068 	retval = usb_submit_urb(urb, GFP_ATOMIC);
1069 	if (retval)
1070 		dev_err(dev, "failed to resubmit arpc in-urb: %d\n", retval);
1071 }
1072 
1073 #define APB1_LOG_MSG_SIZE	64
1074 static void apb_log_get(struct es2_ap_dev *es2, char *buf)
1075 {
1076 	int retval;
1077 
1078 	do {
1079 		retval = usb_control_msg(es2->usb_dev,
1080 					 usb_rcvctrlpipe(es2->usb_dev, 0),
1081 					 GB_APB_REQUEST_LOG,
1082 					 USB_DIR_IN | USB_TYPE_VENDOR |
1083 					 USB_RECIP_INTERFACE,
1084 					 0x00, 0x00,
1085 					 buf,
1086 					 APB1_LOG_MSG_SIZE,
1087 					 ES2_USB_CTRL_TIMEOUT);
1088 		if (retval > 0)
1089 			kfifo_in(&es2->apb_log_fifo, buf, retval);
1090 	} while (retval > 0);
1091 }
1092 
1093 static int apb_log_poll(void *data)
1094 {
1095 	struct es2_ap_dev *es2 = data;
1096 	char *buf;
1097 
1098 	buf = kmalloc(APB1_LOG_MSG_SIZE, GFP_KERNEL);
1099 	if (!buf)
1100 		return -ENOMEM;
1101 
1102 	while (!kthread_should_stop()) {
1103 		msleep(1000);
1104 		apb_log_get(es2, buf);
1105 	}
1106 
1107 	kfree(buf);
1108 
1109 	return 0;
1110 }
1111 
1112 static ssize_t apb_log_read(struct file *f, char __user *buf,
1113 			    size_t count, loff_t *ppos)
1114 {
1115 	struct es2_ap_dev *es2 = file_inode(f)->i_private;
1116 	ssize_t ret;
1117 	size_t copied;
1118 	char *tmp_buf;
1119 
1120 	if (count > APB1_LOG_SIZE)
1121 		count = APB1_LOG_SIZE;
1122 
1123 	tmp_buf = kmalloc(count, GFP_KERNEL);
1124 	if (!tmp_buf)
1125 		return -ENOMEM;
1126 
1127 	copied = kfifo_out(&es2->apb_log_fifo, tmp_buf, count);
1128 	ret = simple_read_from_buffer(buf, count, ppos, tmp_buf, copied);
1129 
1130 	kfree(tmp_buf);
1131 
1132 	return ret;
1133 }
1134 
1135 static const struct file_operations apb_log_fops = {
1136 	.read	= apb_log_read,
1137 };
1138 
1139 static void usb_log_enable(struct es2_ap_dev *es2)
1140 {
1141 	if (!IS_ERR_OR_NULL(es2->apb_log_task))
1142 		return;
1143 
1144 	/* get log from APB1 */
1145 	es2->apb_log_task = kthread_run(apb_log_poll, es2, "apb_log");
1146 	if (IS_ERR(es2->apb_log_task))
1147 		return;
1148 	/* XXX We will need to rename this per APB */
1149 	es2->apb_log_dentry = debugfs_create_file("apb_log", 0444,
1150 						  gb_debugfs_get(), es2,
1151 						  &apb_log_fops);
1152 }
1153 
1154 static void usb_log_disable(struct es2_ap_dev *es2)
1155 {
1156 	if (IS_ERR_OR_NULL(es2->apb_log_task))
1157 		return;
1158 
1159 	debugfs_remove(es2->apb_log_dentry);
1160 	es2->apb_log_dentry = NULL;
1161 
1162 	kthread_stop(es2->apb_log_task);
1163 	es2->apb_log_task = NULL;
1164 }
1165 
1166 static ssize_t apb_log_enable_read(struct file *f, char __user *buf,
1167 				   size_t count, loff_t *ppos)
1168 {
1169 	struct es2_ap_dev *es2 = file_inode(f)->i_private;
1170 	int enable = !IS_ERR_OR_NULL(es2->apb_log_task);
1171 	char tmp_buf[3];
1172 
1173 	sprintf(tmp_buf, "%d\n", enable);
1174 	return simple_read_from_buffer(buf, count, ppos, tmp_buf, 2);
1175 }
1176 
1177 static ssize_t apb_log_enable_write(struct file *f, const char __user *buf,
1178 				    size_t count, loff_t *ppos)
1179 {
1180 	int enable;
1181 	ssize_t retval;
1182 	struct es2_ap_dev *es2 = file_inode(f)->i_private;
1183 
1184 	retval = kstrtoint_from_user(buf, count, 10, &enable);
1185 	if (retval)
1186 		return retval;
1187 
1188 	if (enable)
1189 		usb_log_enable(es2);
1190 	else
1191 		usb_log_disable(es2);
1192 
1193 	return count;
1194 }
1195 
1196 static const struct file_operations apb_log_enable_fops = {
1197 	.read	= apb_log_enable_read,
1198 	.write	= apb_log_enable_write,
1199 };
1200 
1201 static int apb_get_cport_count(struct usb_device *udev)
1202 {
1203 	int retval;
1204 	__le16 *cport_count;
1205 
1206 	cport_count = kzalloc(sizeof(*cport_count), GFP_KERNEL);
1207 	if (!cport_count)
1208 		return -ENOMEM;
1209 
1210 	retval = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
1211 				 GB_APB_REQUEST_CPORT_COUNT,
1212 				 USB_DIR_IN | USB_TYPE_VENDOR |
1213 				 USB_RECIP_INTERFACE, 0, 0, cport_count,
1214 				 sizeof(*cport_count), ES2_USB_CTRL_TIMEOUT);
1215 	if (retval != sizeof(*cport_count)) {
1216 		dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
1217 			retval);
1218 
1219 		if (retval >= 0)
1220 			retval = -EIO;
1221 
1222 		goto out;
1223 	}
1224 
1225 	retval = le16_to_cpu(*cport_count);
1226 
1227 	/* We need to fit a CPort ID in one byte of a message header */
1228 	if (retval > U8_MAX) {
1229 		retval = U8_MAX;
1230 		dev_warn(&udev->dev, "Limiting number of CPorts to U8_MAX\n");
1231 	}
1232 
1233 out:
1234 	kfree(cport_count);
1235 	return retval;
1236 }
1237 
1238 /*
1239  * The ES2 USB Bridge device has 15 endpoints
1240  * 1 Control - usual USB stuff + AP -> APBridgeA messages
1241  * 7 Bulk IN - CPort data in
1242  * 7 Bulk OUT - CPort data out
1243  */
1244 static int ap_probe(struct usb_interface *interface,
1245 		    const struct usb_device_id *id)
1246 {
1247 	struct es2_ap_dev *es2;
1248 	struct gb_host_device *hd;
1249 	struct usb_device *udev;
1250 	struct usb_host_interface *iface_desc;
1251 	struct usb_endpoint_descriptor *endpoint;
1252 	__u8 ep_addr;
1253 	int retval;
1254 	int i;
1255 	int num_cports;
1256 	bool bulk_out_found = false;
1257 	bool bulk_in_found = false;
1258 	bool arpc_in_found = false;
1259 
1260 	udev = usb_get_dev(interface_to_usbdev(interface));
1261 
1262 	num_cports = apb_get_cport_count(udev);
1263 	if (num_cports < 0) {
1264 		usb_put_dev(udev);
1265 		dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
1266 			num_cports);
1267 		return num_cports;
1268 	}
1269 
1270 	hd = gb_hd_create(&es2_driver, &udev->dev, ES2_GBUF_MSG_SIZE_MAX,
1271 			  num_cports);
1272 	if (IS_ERR(hd)) {
1273 		usb_put_dev(udev);
1274 		return PTR_ERR(hd);
1275 	}
1276 
1277 	es2 = hd_to_es2(hd);
1278 	es2->hd = hd;
1279 	es2->usb_intf = interface;
1280 	es2->usb_dev = udev;
1281 	spin_lock_init(&es2->cport_out_urb_lock);
1282 	INIT_KFIFO(es2->apb_log_fifo);
1283 	usb_set_intfdata(interface, es2);
1284 
1285 	/*
1286 	 * Reserve the CDSI0 and CDSI1 CPorts so they won't be allocated
1287 	 * dynamically.
1288 	 */
1289 	retval = gb_hd_cport_reserve(hd, ES2_CPORT_CDSI0);
1290 	if (retval)
1291 		goto error;
1292 	retval = gb_hd_cport_reserve(hd, ES2_CPORT_CDSI1);
1293 	if (retval)
1294 		goto error;
1295 
1296 	/* find all bulk endpoints */
1297 	iface_desc = interface->cur_altsetting;
1298 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1299 		endpoint = &iface_desc->endpoint[i].desc;
1300 		ep_addr = endpoint->bEndpointAddress;
1301 
1302 		if (usb_endpoint_is_bulk_in(endpoint)) {
1303 			if (!bulk_in_found) {
1304 				es2->cport_in.endpoint = ep_addr;
1305 				bulk_in_found = true;
1306 			} else if (!arpc_in_found) {
1307 				es2->arpc_endpoint_in = ep_addr;
1308 				arpc_in_found = true;
1309 			} else {
1310 				dev_warn(&udev->dev,
1311 					 "Unused bulk IN endpoint found: 0x%02x\n",
1312 					 ep_addr);
1313 			}
1314 			continue;
1315 		}
1316 		if (usb_endpoint_is_bulk_out(endpoint)) {
1317 			if (!bulk_out_found) {
1318 				es2->cport_out_endpoint = ep_addr;
1319 				bulk_out_found = true;
1320 			} else {
1321 				dev_warn(&udev->dev,
1322 					 "Unused bulk OUT endpoint found: 0x%02x\n",
1323 					 ep_addr);
1324 			}
1325 			continue;
1326 		}
1327 		dev_warn(&udev->dev,
1328 			 "Unknown endpoint type found, address 0x%02x\n",
1329 			 ep_addr);
1330 	}
1331 	if (!bulk_in_found || !arpc_in_found || !bulk_out_found) {
1332 		dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n");
1333 		retval = -ENODEV;
1334 		goto error;
1335 	}
1336 
1337 	/* Allocate buffers for our cport in messages */
1338 	for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
1339 		struct urb *urb;
1340 		u8 *buffer;
1341 
1342 		urb = usb_alloc_urb(0, GFP_KERNEL);
1343 		if (!urb) {
1344 			retval = -ENOMEM;
1345 			goto error;
1346 		}
1347 		es2->cport_in.urb[i] = urb;
1348 
1349 		buffer = kmalloc(ES2_GBUF_MSG_SIZE_MAX, GFP_KERNEL);
1350 		if (!buffer) {
1351 			retval = -ENOMEM;
1352 			goto error;
1353 		}
1354 
1355 		usb_fill_bulk_urb(urb, udev,
1356 				  usb_rcvbulkpipe(udev, es2->cport_in.endpoint),
1357 				  buffer, ES2_GBUF_MSG_SIZE_MAX,
1358 				  cport_in_callback, hd);
1359 
1360 		es2->cport_in.buffer[i] = buffer;
1361 	}
1362 
1363 	/* Allocate buffers for ARPC in messages */
1364 	for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
1365 		struct urb *urb;
1366 		u8 *buffer;
1367 
1368 		urb = usb_alloc_urb(0, GFP_KERNEL);
1369 		if (!urb) {
1370 			retval = -ENOMEM;
1371 			goto error;
1372 		}
1373 		es2->arpc_urb[i] = urb;
1374 
1375 		buffer = kmalloc(ARPC_IN_SIZE_MAX, GFP_KERNEL);
1376 		if (!buffer) {
1377 			retval = -ENOMEM;
1378 			goto error;
1379 		}
1380 
1381 		usb_fill_bulk_urb(urb, udev,
1382 				  usb_rcvbulkpipe(udev,
1383 						  es2->arpc_endpoint_in),
1384 				  buffer, ARPC_IN_SIZE_MAX,
1385 				  arpc_in_callback, es2);
1386 
1387 		es2->arpc_buffer[i] = buffer;
1388 	}
1389 
1390 	/* Allocate urbs for our CPort OUT messages */
1391 	for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
1392 		struct urb *urb;
1393 
1394 		urb = usb_alloc_urb(0, GFP_KERNEL);
1395 		if (!urb) {
1396 			retval = -ENOMEM;
1397 			goto error;
1398 		}
1399 
1400 		es2->cport_out_urb[i] = urb;
1401 		es2->cport_out_urb_busy[i] = false;	/* just to be anal */
1402 	}
1403 
1404 	/* XXX We will need to rename this per APB */
1405 	es2->apb_log_enable_dentry = debugfs_create_file("apb_log_enable",
1406 							 0644,
1407 							 gb_debugfs_get(), es2,
1408 							 &apb_log_enable_fops);
1409 
1410 	INIT_LIST_HEAD(&es2->arpcs);
1411 	spin_lock_init(&es2->arpc_lock);
1412 
1413 	retval = es2_arpc_in_enable(es2);
1414 	if (retval)
1415 		goto error;
1416 
1417 	retval = gb_hd_add(hd);
1418 	if (retval)
1419 		goto err_disable_arpc_in;
1420 
1421 	retval = es2_cport_in_enable(es2, &es2->cport_in);
1422 	if (retval)
1423 		goto err_hd_del;
1424 
1425 	return 0;
1426 
1427 err_hd_del:
1428 	gb_hd_del(hd);
1429 err_disable_arpc_in:
1430 	es2_arpc_in_disable(es2);
1431 error:
1432 	es2_destroy(es2);
1433 
1434 	return retval;
1435 }
1436 
1437 static void ap_disconnect(struct usb_interface *interface)
1438 {
1439 	struct es2_ap_dev *es2 = usb_get_intfdata(interface);
1440 
1441 	gb_hd_del(es2->hd);
1442 
1443 	es2_cport_in_disable(es2, &es2->cport_in);
1444 	es2_arpc_in_disable(es2);
1445 
1446 	es2_destroy(es2);
1447 }
1448 
1449 static struct usb_driver es2_ap_driver = {
1450 	.name =		"es2_ap_driver",
1451 	.probe =	ap_probe,
1452 	.disconnect =	ap_disconnect,
1453 	.id_table =	id_table,
1454 	.soft_unbind =	1,
1455 };
1456 
1457 module_usb_driver(es2_ap_driver);
1458 
1459 MODULE_DESCRIPTION("Greybus AP USB driver for ES2 controller chips");
1460 MODULE_LICENSE("GPL v2");
1461 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");
1462