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1 /*
2  * Gadget Function Driver for MTP
3  *
4  * Copyright (C) 2010 Google, Inc.
5  * Author: Mike Lockwood <lockwood@android.com>
6  *
7  * This software is licensed under the terms of the GNU General Public
8  * License version 2, as published by the Free Software Foundation, and
9  * may be copied, distributed, and modified under those terms.
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  */
17 
18 /* #define DEBUG */
19 /* #define VERBOSE_DEBUG */
20 
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/poll.h>
24 #include <linux/delay.h>
25 #include <linux/wait.h>
26 #include <linux/err.h>
27 #include <linux/interrupt.h>
28 
29 #include <linux/types.h>
30 #include <linux/file.h>
31 #include <linux/device.h>
32 #include <linux/miscdevice.h>
33 
34 #include <linux/usb.h>
35 #include <linux/usb_usual.h>
36 #include <linux/usb/ch9.h>
37 #include <linux/usb/f_mtp.h>
38 #include <linux/configfs.h>
39 #include <linux/usb/composite.h>
40 
41 #include "configfs.h"
42 
43 #define MTP_BULK_BUFFER_SIZE       16384
44 #define INTR_BUFFER_SIZE           28
45 #define MAX_INST_NAME_LEN          40
46 #define MTP_MAX_FILE_SIZE          0xFFFFFFFFL
47 
48 /* String IDs */
49 #define INTERFACE_STRING_INDEX	0
50 
51 /* values for mtp_dev.state */
52 #define STATE_OFFLINE               0   /* initial state, disconnected */
53 #define STATE_READY                 1   /* ready for userspace calls */
54 #define STATE_BUSY                  2   /* processing userspace calls */
55 #define STATE_CANCELED              3   /* transaction canceled by host */
56 #define STATE_ERROR                 4   /* error from completion routine */
57 
58 /* number of tx and rx requests to allocate */
59 #define TX_REQ_MAX 4
60 #define RX_REQ_MAX 2
61 #define INTR_REQ_MAX 5
62 
63 /* ID for Microsoft MTP OS String */
64 #define MTP_OS_STRING_ID   0xEE
65 
66 /* MTP class reqeusts */
67 #define MTP_REQ_CANCEL              0x64
68 #define MTP_REQ_GET_EXT_EVENT_DATA  0x65
69 #define MTP_REQ_RESET               0x66
70 #define MTP_REQ_GET_DEVICE_STATUS   0x67
71 
72 /* constants for device status */
73 #define MTP_RESPONSE_OK             0x2001
74 #define MTP_RESPONSE_DEVICE_BUSY    0x2019
75 #define DRIVER_NAME "mtp"
76 
77 static const char mtp_shortname[] = DRIVER_NAME "_usb";
78 
79 struct mtp_dev {
80 	struct usb_function function;
81 	struct usb_composite_dev *cdev;
82 	spinlock_t lock;
83 
84 	struct usb_ep *ep_in;
85 	struct usb_ep *ep_out;
86 	struct usb_ep *ep_intr;
87 
88 	int state;
89 
90 	/* synchronize access to our device file */
91 	atomic_t open_excl;
92 	/* to enforce only one ioctl at a time */
93 	atomic_t ioctl_excl;
94 
95 	struct list_head tx_idle;
96 	struct list_head intr_idle;
97 
98 	wait_queue_head_t read_wq;
99 	wait_queue_head_t write_wq;
100 	wait_queue_head_t intr_wq;
101 	struct usb_request *rx_req[RX_REQ_MAX];
102 	int rx_done;
103 
104 	/* for processing MTP_SEND_FILE, MTP_RECEIVE_FILE and
105 	 * MTP_SEND_FILE_WITH_HEADER ioctls on a work queue
106 	 */
107 	struct workqueue_struct *wq;
108 	struct work_struct send_file_work;
109 	struct work_struct receive_file_work;
110 	struct file *xfer_file;
111 	loff_t xfer_file_offset;
112 	int64_t xfer_file_length;
113 	unsigned xfer_send_header;
114 	uint16_t xfer_command;
115 	uint32_t xfer_transaction_id;
116 	int xfer_result;
117 };
118 
119 static struct usb_interface_descriptor mtp_interface_desc = {
120 	.bLength                = USB_DT_INTERFACE_SIZE,
121 	.bDescriptorType        = USB_DT_INTERFACE,
122 	.bInterfaceNumber       = 0,
123 	.bNumEndpoints          = 3,
124 	.bInterfaceClass        = USB_CLASS_VENDOR_SPEC,
125 	.bInterfaceSubClass     = USB_SUBCLASS_VENDOR_SPEC,
126 	.bInterfaceProtocol     = 0,
127 };
128 
129 static struct usb_interface_descriptor ptp_interface_desc = {
130 	.bLength                = USB_DT_INTERFACE_SIZE,
131 	.bDescriptorType        = USB_DT_INTERFACE,
132 	.bInterfaceNumber       = 0,
133 	.bNumEndpoints          = 3,
134 	.bInterfaceClass        = USB_CLASS_STILL_IMAGE,
135 	.bInterfaceSubClass     = 1,
136 	.bInterfaceProtocol     = 1,
137 };
138 
139 static struct usb_endpoint_descriptor mtp_ss_in_desc = {
140 	.bLength                = USB_DT_ENDPOINT_SIZE,
141 	.bDescriptorType        = USB_DT_ENDPOINT,
142 	.bEndpointAddress       = USB_DIR_IN,
143 	.bmAttributes           = USB_ENDPOINT_XFER_BULK,
144 	.wMaxPacketSize         = __constant_cpu_to_le16(1024),
145 };
146 
147 static struct usb_ss_ep_comp_descriptor mtp_ss_in_comp_desc = {
148 	.bLength                = sizeof(mtp_ss_in_comp_desc),
149 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
150 	/* .bMaxBurst           = DYNAMIC, */
151 };
152 
153 static struct usb_endpoint_descriptor mtp_ss_out_desc = {
154 	.bLength                = USB_DT_ENDPOINT_SIZE,
155 	.bDescriptorType        = USB_DT_ENDPOINT,
156 	.bEndpointAddress       = USB_DIR_OUT,
157 	.bmAttributes           = USB_ENDPOINT_XFER_BULK,
158 	.wMaxPacketSize         = __constant_cpu_to_le16(1024),
159 };
160 
161 static struct usb_ss_ep_comp_descriptor mtp_ss_out_comp_desc = {
162 	.bLength                = sizeof(mtp_ss_out_comp_desc),
163 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
164 	/* .bMaxBurst           = DYNAMIC, */
165 };
166 
167 static struct usb_endpoint_descriptor mtp_highspeed_in_desc = {
168 	.bLength                = USB_DT_ENDPOINT_SIZE,
169 	.bDescriptorType        = USB_DT_ENDPOINT,
170 	.bEndpointAddress       = USB_DIR_IN,
171 	.bmAttributes           = USB_ENDPOINT_XFER_BULK,
172 	.wMaxPacketSize         = __constant_cpu_to_le16(512),
173 };
174 
175 static struct usb_endpoint_descriptor mtp_highspeed_out_desc = {
176 	.bLength                = USB_DT_ENDPOINT_SIZE,
177 	.bDescriptorType        = USB_DT_ENDPOINT,
178 	.bEndpointAddress       = USB_DIR_OUT,
179 	.bmAttributes           = USB_ENDPOINT_XFER_BULK,
180 	.wMaxPacketSize         = __constant_cpu_to_le16(512),
181 };
182 
183 static struct usb_endpoint_descriptor mtp_fullspeed_in_desc = {
184 	.bLength                = USB_DT_ENDPOINT_SIZE,
185 	.bDescriptorType        = USB_DT_ENDPOINT,
186 	.bEndpointAddress       = USB_DIR_IN,
187 	.bmAttributes           = USB_ENDPOINT_XFER_BULK,
188 };
189 
190 static struct usb_endpoint_descriptor mtp_fullspeed_out_desc = {
191 	.bLength                = USB_DT_ENDPOINT_SIZE,
192 	.bDescriptorType        = USB_DT_ENDPOINT,
193 	.bEndpointAddress       = USB_DIR_OUT,
194 	.bmAttributes           = USB_ENDPOINT_XFER_BULK,
195 };
196 
197 static struct usb_endpoint_descriptor mtp_intr_desc = {
198 	.bLength                = USB_DT_ENDPOINT_SIZE,
199 	.bDescriptorType        = USB_DT_ENDPOINT,
200 	.bEndpointAddress       = USB_DIR_IN,
201 	.bmAttributes           = USB_ENDPOINT_XFER_INT,
202 	.wMaxPacketSize         = __constant_cpu_to_le16(INTR_BUFFER_SIZE),
203 	.bInterval              = 6,
204 };
205 
206 static struct usb_ss_ep_comp_descriptor mtp_intr_ss_comp_desc = {
207 	.bLength                = sizeof(mtp_intr_ss_comp_desc),
208 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
209 	.wBytesPerInterval      = cpu_to_le16(INTR_BUFFER_SIZE),
210 };
211 
212 static struct usb_descriptor_header *fs_mtp_descs[] = {
213 	(struct usb_descriptor_header *) &mtp_interface_desc,
214 	(struct usb_descriptor_header *) &mtp_fullspeed_in_desc,
215 	(struct usb_descriptor_header *) &mtp_fullspeed_out_desc,
216 	(struct usb_descriptor_header *) &mtp_intr_desc,
217 	NULL,
218 };
219 
220 static struct usb_descriptor_header *hs_mtp_descs[] = {
221 	(struct usb_descriptor_header *) &mtp_interface_desc,
222 	(struct usb_descriptor_header *) &mtp_highspeed_in_desc,
223 	(struct usb_descriptor_header *) &mtp_highspeed_out_desc,
224 	(struct usb_descriptor_header *) &mtp_intr_desc,
225 	NULL,
226 };
227 
228 static struct usb_descriptor_header *ss_mtp_descs[] = {
229 	(struct usb_descriptor_header *) &mtp_interface_desc,
230 	(struct usb_descriptor_header *) &mtp_ss_in_desc,
231 	(struct usb_descriptor_header *) &mtp_ss_in_comp_desc,
232 	(struct usb_descriptor_header *) &mtp_ss_out_desc,
233 	(struct usb_descriptor_header *) &mtp_ss_out_comp_desc,
234 	(struct usb_descriptor_header *) &mtp_intr_desc,
235 	(struct usb_descriptor_header *) &mtp_intr_ss_comp_desc,
236 	NULL,
237 };
238 
239 static struct usb_descriptor_header *fs_ptp_descs[] = {
240 	(struct usb_descriptor_header *) &ptp_interface_desc,
241 	(struct usb_descriptor_header *) &mtp_fullspeed_in_desc,
242 	(struct usb_descriptor_header *) &mtp_fullspeed_out_desc,
243 	(struct usb_descriptor_header *) &mtp_intr_desc,
244 	NULL,
245 };
246 
247 static struct usb_descriptor_header *hs_ptp_descs[] = {
248 	(struct usb_descriptor_header *) &ptp_interface_desc,
249 	(struct usb_descriptor_header *) &mtp_highspeed_in_desc,
250 	(struct usb_descriptor_header *) &mtp_highspeed_out_desc,
251 	(struct usb_descriptor_header *) &mtp_intr_desc,
252 	NULL,
253 };
254 
255 static struct usb_descriptor_header *ss_ptp_descs[] = {
256 	(struct usb_descriptor_header *) &ptp_interface_desc,
257 	(struct usb_descriptor_header *) &mtp_ss_in_desc,
258 	(struct usb_descriptor_header *) &mtp_ss_in_comp_desc,
259 	(struct usb_descriptor_header *) &mtp_ss_out_desc,
260 	(struct usb_descriptor_header *) &mtp_ss_out_comp_desc,
261 	(struct usb_descriptor_header *) &mtp_intr_desc,
262 	(struct usb_descriptor_header *) &mtp_intr_ss_comp_desc,
263 	NULL,
264 };
265 
266 static struct usb_string mtp_string_defs[] = {
267 	/* Naming interface "MTP" so libmtp will recognize us */
268 	[INTERFACE_STRING_INDEX].s	= "MTP",
269 	{  },	/* end of list */
270 };
271 
272 static struct usb_gadget_strings mtp_string_table = {
273 	.language		= 0x0409,	/* en-US */
274 	.strings		= mtp_string_defs,
275 };
276 
277 static struct usb_gadget_strings *mtp_strings[] = {
278 	&mtp_string_table,
279 	NULL,
280 };
281 
282 /* Microsoft MTP OS String */
283 static u8 mtp_os_string[] = {
284 	18, /* sizeof(mtp_os_string) */
285 	USB_DT_STRING,
286 	/* Signature field: "MSFT100" */
287 	'M', 0, 'S', 0, 'F', 0, 'T', 0, '1', 0, '0', 0, '0', 0,
288 	/* vendor code */
289 	1,
290 	/* padding */
291 	0
292 };
293 
294 /* Microsoft Extended Configuration Descriptor Header Section */
295 struct mtp_ext_config_desc_header {
296 	__le32	dwLength;
297 	__u16	bcdVersion;
298 	__le16	wIndex;
299 	__u8	bCount;
300 	__u8	reserved[7];
301 };
302 
303 /* Microsoft Extended Configuration Descriptor Function Section */
304 struct mtp_ext_config_desc_function {
305 	__u8	bFirstInterfaceNumber;
306 	__u8	bInterfaceCount;
307 	__u8	compatibleID[8];
308 	__u8	subCompatibleID[8];
309 	__u8	reserved[6];
310 };
311 
312 /* MTP Extended Configuration Descriptor */
313 struct {
314 	struct mtp_ext_config_desc_header	header;
315 	struct mtp_ext_config_desc_function    function;
316 } mtp_ext_config_desc = {
317 	.header = {
318 		.dwLength = __constant_cpu_to_le32(sizeof(mtp_ext_config_desc)),
319 		.bcdVersion = __constant_cpu_to_le16(0x0100),
320 		.wIndex = __constant_cpu_to_le16(4),
321 		.bCount = 1,
322 	},
323 	.function = {
324 		.bFirstInterfaceNumber = 0,
325 		.bInterfaceCount = 1,
326 		.compatibleID = { 'M', 'T', 'P' },
327 	},
328 };
329 
330 struct mtp_device_status {
331 	__le16	wLength;
332 	__le16	wCode;
333 };
334 
335 struct mtp_data_header {
336 	/* length of packet, including this header */
337 	__le32	length;
338 	/* container type (2 for data packet) */
339 	__le16	type;
340 	/* MTP command code */
341 	__le16	command;
342 	/* MTP transaction ID */
343 	__le32	transaction_id;
344 };
345 
346 struct mtp_instance {
347 	struct usb_function_instance func_inst;
348 	const char *name;
349 	struct mtp_dev *dev;
350 	char mtp_ext_compat_id[16];
351 	struct usb_os_desc mtp_os_desc;
352 };
353 
354 /* temporary variable used between mtp_open() and mtp_gadget_bind() */
355 static struct mtp_dev *_mtp_dev;
356 
func_to_mtp(struct usb_function * f)357 static inline struct mtp_dev *func_to_mtp(struct usb_function *f)
358 {
359 	return container_of(f, struct mtp_dev, function);
360 }
361 
mtp_request_new(struct usb_ep * ep,int buffer_size)362 static struct usb_request *mtp_request_new(struct usb_ep *ep, int buffer_size)
363 {
364 	struct usb_request *req = usb_ep_alloc_request(ep, GFP_KERNEL);
365 
366 	if (!req)
367 		return NULL;
368 
369 	/* now allocate buffers for the requests */
370 	req->buf = kmalloc(buffer_size, GFP_KERNEL);
371 	if (!req->buf) {
372 		usb_ep_free_request(ep, req);
373 		return NULL;
374 	}
375 
376 	return req;
377 }
378 
mtp_request_free(struct usb_request * req,struct usb_ep * ep)379 static void mtp_request_free(struct usb_request *req, struct usb_ep *ep)
380 {
381 	if (req) {
382 		kfree(req->buf);
383 		usb_ep_free_request(ep, req);
384 	}
385 }
386 
mtp_lock(atomic_t * excl)387 static inline int mtp_lock(atomic_t *excl)
388 {
389 	if (atomic_inc_return(excl) == 1) {
390 		return 0;
391 	} else {
392 		atomic_dec(excl);
393 		return -1;
394 	}
395 }
396 
mtp_unlock(atomic_t * excl)397 static inline void mtp_unlock(atomic_t *excl)
398 {
399 	atomic_dec(excl);
400 }
401 
402 /* add a request to the tail of a list */
mtp_req_put(struct mtp_dev * dev,struct list_head * head,struct usb_request * req)403 static void mtp_req_put(struct mtp_dev *dev, struct list_head *head,
404 		struct usb_request *req)
405 {
406 	unsigned long flags;
407 
408 	spin_lock_irqsave(&dev->lock, flags);
409 	list_add_tail(&req->list, head);
410 	spin_unlock_irqrestore(&dev->lock, flags);
411 }
412 
413 /* remove a request from the head of a list */
414 static struct usb_request
mtp_req_get(struct mtp_dev * dev,struct list_head * head)415 *mtp_req_get(struct mtp_dev *dev, struct list_head *head)
416 {
417 	unsigned long flags;
418 	struct usb_request *req;
419 
420 	spin_lock_irqsave(&dev->lock, flags);
421 	if (list_empty(head)) {
422 		req = 0;
423 	} else {
424 		req = list_first_entry(head, struct usb_request, list);
425 		list_del(&req->list);
426 	}
427 	spin_unlock_irqrestore(&dev->lock, flags);
428 	return req;
429 }
430 
mtp_complete_in(struct usb_ep * ep,struct usb_request * req)431 static void mtp_complete_in(struct usb_ep *ep, struct usb_request *req)
432 {
433 	struct mtp_dev *dev = _mtp_dev;
434 
435 	if (req->status != 0)
436 		dev->state = STATE_ERROR;
437 
438 	mtp_req_put(dev, &dev->tx_idle, req);
439 
440 	wake_up(&dev->write_wq);
441 }
442 
mtp_complete_out(struct usb_ep * ep,struct usb_request * req)443 static void mtp_complete_out(struct usb_ep *ep, struct usb_request *req)
444 {
445 	struct mtp_dev *dev = _mtp_dev;
446 
447 	dev->rx_done = 1;
448 	if (req->status != 0)
449 		dev->state = STATE_ERROR;
450 
451 	wake_up(&dev->read_wq);
452 }
453 
mtp_complete_intr(struct usb_ep * ep,struct usb_request * req)454 static void mtp_complete_intr(struct usb_ep *ep, struct usb_request *req)
455 {
456 	struct mtp_dev *dev = _mtp_dev;
457 
458 	if (req->status != 0)
459 		dev->state = STATE_ERROR;
460 
461 	mtp_req_put(dev, &dev->intr_idle, req);
462 
463 	wake_up(&dev->intr_wq);
464 }
465 
mtp_create_bulk_endpoints(struct mtp_dev * dev,struct usb_endpoint_descriptor * in_desc,struct usb_endpoint_descriptor * out_desc,struct usb_endpoint_descriptor * intr_desc)466 static int mtp_create_bulk_endpoints(struct mtp_dev *dev,
467 				struct usb_endpoint_descriptor *in_desc,
468 				struct usb_endpoint_descriptor *out_desc,
469 				struct usb_endpoint_descriptor *intr_desc)
470 {
471 	struct usb_composite_dev *cdev = dev->cdev;
472 	struct usb_request *req;
473 	struct usb_ep *ep;
474 	int i;
475 
476 	DBG(cdev, "create_bulk_endpoints dev: %p\n", dev);
477 
478 	ep = usb_ep_autoconfig(cdev->gadget, in_desc);
479 	if (!ep) {
480 		DBG(cdev, "usb_ep_autoconfig for ep_in failed\n");
481 		return -ENODEV;
482 	}
483 	DBG(cdev, "usb_ep_autoconfig for ep_in got %s\n", ep->name);
484 	ep->driver_data = dev;		/* claim the endpoint */
485 	dev->ep_in = ep;
486 
487 	ep = usb_ep_autoconfig(cdev->gadget, out_desc);
488 	if (!ep) {
489 		DBG(cdev, "usb_ep_autoconfig for ep_out failed\n");
490 		return -ENODEV;
491 	}
492 	DBG(cdev, "usb_ep_autoconfig for mtp ep_out got %s\n", ep->name);
493 	ep->driver_data = dev;		/* claim the endpoint */
494 	dev->ep_out = ep;
495 
496 	ep = usb_ep_autoconfig(cdev->gadget, intr_desc);
497 	if (!ep) {
498 		DBG(cdev, "usb_ep_autoconfig for ep_intr failed\n");
499 		return -ENODEV;
500 	}
501 	DBG(cdev, "usb_ep_autoconfig for mtp ep_intr got %s\n", ep->name);
502 	ep->driver_data = dev;		/* claim the endpoint */
503 	dev->ep_intr = ep;
504 
505 	/* now allocate requests for our endpoints */
506 	for (i = 0; i < TX_REQ_MAX; i++) {
507 		req = mtp_request_new(dev->ep_in, MTP_BULK_BUFFER_SIZE);
508 		if (!req)
509 			goto fail;
510 		req->complete = mtp_complete_in;
511 		mtp_req_put(dev, &dev->tx_idle, req);
512 	}
513 	for (i = 0; i < RX_REQ_MAX; i++) {
514 		req = mtp_request_new(dev->ep_out, MTP_BULK_BUFFER_SIZE);
515 		if (!req)
516 			goto fail;
517 		req->complete = mtp_complete_out;
518 		dev->rx_req[i] = req;
519 	}
520 	for (i = 0; i < INTR_REQ_MAX; i++) {
521 		req = mtp_request_new(dev->ep_intr, INTR_BUFFER_SIZE);
522 		if (!req)
523 			goto fail;
524 		req->complete = mtp_complete_intr;
525 		mtp_req_put(dev, &dev->intr_idle, req);
526 	}
527 
528 	return 0;
529 
530 fail:
531 	pr_err("mtp_bind() could not allocate requests\n");
532 	return -1;
533 }
534 
mtp_read(struct file * fp,char __user * buf,size_t count,loff_t * pos)535 static ssize_t mtp_read(struct file *fp, char __user *buf,
536 	size_t count, loff_t *pos)
537 {
538 	struct mtp_dev *dev = fp->private_data;
539 	struct usb_composite_dev *cdev = dev->cdev;
540 	struct usb_request *req;
541 	ssize_t r = count;
542 	unsigned xfer;
543 	int ret = 0;
544 	size_t len = 0;
545 
546 	DBG(cdev, "mtp_read(%zu)\n", count);
547 
548 	/* we will block until we're online */
549 	DBG(cdev, "mtp_read: waiting for online state\n");
550 	ret = wait_event_interruptible(dev->read_wq,
551 		dev->state != STATE_OFFLINE);
552 	if (ret < 0) {
553 		r = ret;
554 		goto done;
555 	}
556 	spin_lock_irq(&dev->lock);
557 	if (dev->ep_out->desc) {
558 		len = usb_ep_align_maybe(cdev->gadget, dev->ep_out, count);
559 		if (len > MTP_BULK_BUFFER_SIZE) {
560 			spin_unlock_irq(&dev->lock);
561 			return -EINVAL;
562 		}
563 	}
564 
565 	if (dev->state == STATE_CANCELED) {
566 		/* report cancelation to userspace */
567 		dev->state = STATE_READY;
568 		spin_unlock_irq(&dev->lock);
569 		return -ECANCELED;
570 	}
571 	dev->state = STATE_BUSY;
572 	spin_unlock_irq(&dev->lock);
573 
574 requeue_req:
575 	/* queue a request */
576 	req = dev->rx_req[0];
577 	req->length = len;
578 	dev->rx_done = 0;
579 	ret = usb_ep_queue(dev->ep_out, req, GFP_KERNEL);
580 	if (ret < 0) {
581 		r = -EIO;
582 		goto done;
583 	} else {
584 		DBG(cdev, "rx %p queue\n", req);
585 	}
586 
587 	/* wait for a request to complete */
588 	ret = wait_event_interruptible(dev->read_wq, dev->rx_done);
589 	if (ret < 0) {
590 		r = ret;
591 		usb_ep_dequeue(dev->ep_out, req);
592 		goto done;
593 	}
594 	if (dev->state == STATE_BUSY) {
595 		/* If we got a 0-len packet, throw it back and try again. */
596 		if (req->actual == 0)
597 			goto requeue_req;
598 
599 		DBG(cdev, "rx %p %d\n", req, req->actual);
600 		xfer = (req->actual < count) ? req->actual : count;
601 		r = xfer;
602 		if (copy_to_user(buf, req->buf, xfer))
603 			r = -EFAULT;
604 	} else
605 		r = -EIO;
606 
607 done:
608 	spin_lock_irq(&dev->lock);
609 	if (dev->state == STATE_CANCELED)
610 		r = -ECANCELED;
611 	else if (dev->state != STATE_OFFLINE)
612 		dev->state = STATE_READY;
613 	spin_unlock_irq(&dev->lock);
614 
615 	DBG(cdev, "mtp_read returning %zd\n", r);
616 	return r;
617 }
618 
mtp_write(struct file * fp,const char __user * buf,size_t count,loff_t * pos)619 static ssize_t mtp_write(struct file *fp, const char __user *buf,
620 	size_t count, loff_t *pos)
621 {
622 	struct mtp_dev *dev = fp->private_data;
623 	struct usb_composite_dev *cdev = dev->cdev;
624 	struct usb_request *req = 0;
625 	ssize_t r = count;
626 	unsigned xfer;
627 	int sendZLP = 0;
628 	int ret;
629 
630 	DBG(cdev, "mtp_write(%zu)\n", count);
631 
632 	spin_lock_irq(&dev->lock);
633 	if (dev->state == STATE_CANCELED) {
634 		/* report cancelation to userspace */
635 		dev->state = STATE_READY;
636 		spin_unlock_irq(&dev->lock);
637 		return -ECANCELED;
638 	}
639 	if (dev->state == STATE_OFFLINE) {
640 		spin_unlock_irq(&dev->lock);
641 		return -ENODEV;
642 	}
643 	dev->state = STATE_BUSY;
644 	spin_unlock_irq(&dev->lock);
645 
646 	/* we need to send a zero length packet to signal the end of transfer
647 	 * if the transfer size is aligned to a packet boundary.
648 	 */
649 	if ((count & (dev->ep_in->maxpacket - 1)) == 0)
650 		sendZLP = 1;
651 
652 	while (count > 0 || sendZLP) {
653 		/* so we exit after sending ZLP */
654 		if (count == 0)
655 			sendZLP = 0;
656 
657 		if (dev->state != STATE_BUSY) {
658 			DBG(cdev, "mtp_write dev->error\n");
659 			r = -EIO;
660 			break;
661 		}
662 
663 		/* get an idle tx request to use */
664 		req = 0;
665 		ret = wait_event_interruptible(dev->write_wq,
666 			((req = mtp_req_get(dev, &dev->tx_idle))
667 				|| dev->state != STATE_BUSY));
668 		if (!req) {
669 			r = ret;
670 			break;
671 		}
672 
673 		if (count > MTP_BULK_BUFFER_SIZE)
674 			xfer = MTP_BULK_BUFFER_SIZE;
675 		else
676 			xfer = count;
677 		if (xfer && copy_from_user(req->buf, buf, xfer)) {
678 			r = -EFAULT;
679 			break;
680 		}
681 
682 		req->length = xfer;
683 		ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL);
684 		if (ret < 0) {
685 			DBG(cdev, "mtp_write: xfer error %d\n", ret);
686 			r = -EIO;
687 			break;
688 		}
689 
690 		buf += xfer;
691 		count -= xfer;
692 
693 		/* zero this so we don't try to free it on error exit */
694 		req = 0;
695 	}
696 
697 	if (req)
698 		mtp_req_put(dev, &dev->tx_idle, req);
699 
700 	spin_lock_irq(&dev->lock);
701 	if (dev->state == STATE_CANCELED)
702 		r = -ECANCELED;
703 	else if (dev->state != STATE_OFFLINE)
704 		dev->state = STATE_READY;
705 	spin_unlock_irq(&dev->lock);
706 
707 	DBG(cdev, "mtp_write returning %zd\n", r);
708 	return r;
709 }
710 
711 /* read from a local file and write to USB */
send_file_work(struct work_struct * data)712 static void send_file_work(struct work_struct *data)
713 {
714 	struct mtp_dev *dev = container_of(data, struct mtp_dev,
715 						send_file_work);
716 	struct usb_composite_dev *cdev = dev->cdev;
717 	struct usb_request *req = 0;
718 	struct mtp_data_header *header;
719 	struct file *filp;
720 	loff_t offset;
721 	int64_t count;
722 	int xfer, ret, hdr_size;
723 	int r = 0;
724 	int sendZLP = 0;
725 
726 	/* read our parameters */
727 	smp_rmb();
728 	filp = dev->xfer_file;
729 	offset = dev->xfer_file_offset;
730 	count = dev->xfer_file_length;
731 
732 	DBG(cdev, "send_file_work(%lld %lld)\n", offset, count);
733 
734 	if (dev->xfer_send_header) {
735 		hdr_size = sizeof(struct mtp_data_header);
736 		count += hdr_size;
737 	} else {
738 		hdr_size = 0;
739 	}
740 
741 	/* we need to send a zero length packet to signal the end of transfer
742 	 * if the transfer size is aligned to a packet boundary.
743 	 */
744 	if ((count & (dev->ep_in->maxpacket - 1)) == 0)
745 		sendZLP = 1;
746 
747 	while (count > 0 || sendZLP) {
748 		/* so we exit after sending ZLP */
749 		if (count == 0)
750 			sendZLP = 0;
751 
752 		/* get an idle tx request to use */
753 		req = 0;
754 		ret = wait_event_interruptible(dev->write_wq,
755 			(req = mtp_req_get(dev, &dev->tx_idle))
756 			|| dev->state != STATE_BUSY);
757 		if (dev->state == STATE_CANCELED) {
758 			r = -ECANCELED;
759 			break;
760 		}
761 		if (!req) {
762 			r = ret;
763 			break;
764 		}
765 
766 		if (count > MTP_BULK_BUFFER_SIZE)
767 			xfer = MTP_BULK_BUFFER_SIZE;
768 		else
769 			xfer = count;
770 
771 		if (hdr_size) {
772 			/* prepend MTP data header */
773 			header = (struct mtp_data_header *)req->buf;
774 			/*
775                          * set file size with header according to
776                          * MTP Specification v1.0
777                          */
778 			header->length = (count > MTP_MAX_FILE_SIZE) ?
779 				MTP_MAX_FILE_SIZE : __cpu_to_le32(count);
780 			header->type = __cpu_to_le16(2); /* data packet */
781 			header->command = __cpu_to_le16(dev->xfer_command);
782 			header->transaction_id =
783 					__cpu_to_le32(dev->xfer_transaction_id);
784 		}
785 
786 		ret = vfs_read(filp, req->buf + hdr_size, xfer - hdr_size,
787 								&offset);
788 		if (ret < 0) {
789 			r = ret;
790 			break;
791 		}
792 		xfer = ret + hdr_size;
793 		hdr_size = 0;
794 
795 		req->length = xfer;
796 		ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL);
797 		if (ret < 0) {
798 			DBG(cdev, "send_file_work: xfer error %d\n", ret);
799 			dev->state = STATE_ERROR;
800 			r = -EIO;
801 			break;
802 		}
803 
804 		count -= xfer;
805 
806 		/* zero this so we don't try to free it on error exit */
807 		req = 0;
808 	}
809 
810 	if (req)
811 		mtp_req_put(dev, &dev->tx_idle, req);
812 
813 	DBG(cdev, "send_file_work returning %d\n", r);
814 	/* write the result */
815 	dev->xfer_result = r;
816 	smp_wmb();
817 }
818 
819 /* read from USB and write to a local file */
receive_file_work(struct work_struct * data)820 static void receive_file_work(struct work_struct *data)
821 {
822 	struct mtp_dev *dev = container_of(data, struct mtp_dev,
823 						receive_file_work);
824 	struct usb_composite_dev *cdev = dev->cdev;
825 	struct usb_request *read_req = NULL, *write_req = NULL;
826 	struct file *filp;
827 	loff_t offset;
828 	int64_t count;
829 	int ret, cur_buf = 0;
830 	int r = 0;
831 
832 	/* read our parameters */
833 	smp_rmb();
834 	filp = dev->xfer_file;
835 	offset = dev->xfer_file_offset;
836 	count = dev->xfer_file_length;
837 
838 	DBG(cdev, "receive_file_work(%lld)\n", count);
839 
840 	while (count > 0 || write_req) {
841 		if (count > 0) {
842 			/* queue a request */
843 			read_req = dev->rx_req[cur_buf];
844 			cur_buf = (cur_buf + 1) % RX_REQ_MAX;
845 
846 			read_req->length = (count > MTP_BULK_BUFFER_SIZE
847 					? MTP_BULK_BUFFER_SIZE : count);
848 			dev->rx_done = 0;
849 			ret = usb_ep_queue(dev->ep_out, read_req, GFP_KERNEL);
850 			if (ret < 0) {
851 				r = -EIO;
852 				dev->state = STATE_ERROR;
853 				break;
854 			}
855 		}
856 
857 		if (write_req) {
858 			DBG(cdev, "rx %p %d\n", write_req, write_req->actual);
859 			ret = vfs_write(filp, write_req->buf, write_req->actual,
860 				&offset);
861 			DBG(cdev, "vfs_write %d\n", ret);
862 			if (ret != write_req->actual) {
863 				r = -EIO;
864 				dev->state = STATE_ERROR;
865 				break;
866 			}
867 			write_req = NULL;
868 		}
869 
870 		if (read_req) {
871 			/* wait for our last read to complete */
872 			ret = wait_event_interruptible(dev->read_wq,
873 				dev->rx_done || dev->state != STATE_BUSY);
874 			if (dev->state == STATE_CANCELED) {
875 				r = -ECANCELED;
876 				if (!dev->rx_done)
877 					usb_ep_dequeue(dev->ep_out, read_req);
878 				break;
879 			}
880 			if (read_req->status) {
881 				r = read_req->status;
882 				break;
883 			}
884 			/* if xfer_file_length is 0xFFFFFFFF, then we read until
885 			 * we get a zero length packet
886 			 */
887 			if (count != 0xFFFFFFFF)
888 				count -= read_req->actual;
889 			if (read_req->actual < read_req->length) {
890 				/*
891 				 * short packet is used to signal EOF for
892 				 * sizes > 4 gig
893 				 */
894 				DBG(cdev, "got short packet\n");
895 				count = 0;
896 			}
897 
898 			write_req = read_req;
899 			read_req = NULL;
900 		}
901 	}
902 
903 	DBG(cdev, "receive_file_work returning %d\n", r);
904 	/* write the result */
905 	dev->xfer_result = r;
906 	smp_wmb();
907 }
908 
mtp_send_event(struct mtp_dev * dev,struct mtp_event * event)909 static int mtp_send_event(struct mtp_dev *dev, struct mtp_event *event)
910 {
911 	struct usb_request *req = NULL;
912 	int ret;
913 	int length = event->length;
914 
915 	DBG(dev->cdev, "mtp_send_event(%zu)\n", event->length);
916 
917 	if (length < 0 || length > INTR_BUFFER_SIZE)
918 		return -EINVAL;
919 	if (dev->state == STATE_OFFLINE)
920 		return -ENODEV;
921 
922 	ret = wait_event_interruptible_timeout(dev->intr_wq,
923 			(req = mtp_req_get(dev, &dev->intr_idle)),
924 			msecs_to_jiffies(1000));
925 	if (!req)
926 		return -ETIME;
927 
928 	if (copy_from_user(req->buf, (void __user *)event->data, length)) {
929 		mtp_req_put(dev, &dev->intr_idle, req);
930 		return -EFAULT;
931 	}
932 	req->length = length;
933 	ret = usb_ep_queue(dev->ep_intr, req, GFP_KERNEL);
934 	if (ret)
935 		mtp_req_put(dev, &dev->intr_idle, req);
936 
937 	return ret;
938 }
939 
mtp_ioctl(struct file * fp,unsigned code,unsigned long value)940 static long mtp_ioctl(struct file *fp, unsigned code, unsigned long value)
941 {
942 	struct mtp_dev *dev = fp->private_data;
943 	struct file *filp = NULL;
944 	int ret = -EINVAL;
945 
946 	if (mtp_lock(&dev->ioctl_excl))
947 		return -EBUSY;
948 
949 	switch (code) {
950 	case MTP_SEND_FILE:
951 	case MTP_RECEIVE_FILE:
952 	case MTP_SEND_FILE_WITH_HEADER:
953 	{
954 		struct mtp_file_range	mfr;
955 		struct work_struct *work;
956 
957 		spin_lock_irq(&dev->lock);
958 		if (dev->state == STATE_CANCELED) {
959 			/* report cancelation to userspace */
960 			dev->state = STATE_READY;
961 			spin_unlock_irq(&dev->lock);
962 			ret = -ECANCELED;
963 			goto out;
964 		}
965 		if (dev->state == STATE_OFFLINE) {
966 			spin_unlock_irq(&dev->lock);
967 			ret = -ENODEV;
968 			goto out;
969 		}
970 		dev->state = STATE_BUSY;
971 		spin_unlock_irq(&dev->lock);
972 
973 		if (copy_from_user(&mfr, (void __user *)value, sizeof(mfr))) {
974 			ret = -EFAULT;
975 			goto fail;
976 		}
977 		/* hold a reference to the file while we are working with it */
978 		filp = fget(mfr.fd);
979 		if (!filp) {
980 			ret = -EBADF;
981 			goto fail;
982 		}
983 
984 		/* write the parameters */
985 		dev->xfer_file = filp;
986 		dev->xfer_file_offset = mfr.offset;
987 		dev->xfer_file_length = mfr.length;
988 		smp_wmb();
989 
990 		if (code == MTP_SEND_FILE_WITH_HEADER) {
991 			work = &dev->send_file_work;
992 			dev->xfer_send_header = 1;
993 			dev->xfer_command = mfr.command;
994 			dev->xfer_transaction_id = mfr.transaction_id;
995 		} else if (code == MTP_SEND_FILE) {
996 			work = &dev->send_file_work;
997 			dev->xfer_send_header = 0;
998 		} else {
999 			work = &dev->receive_file_work;
1000 		}
1001 
1002 		/* We do the file transfer on a work queue so it will run
1003 		 * in kernel context, which is necessary for vfs_read and
1004 		 * vfs_write to use our buffers in the kernel address space.
1005 		 */
1006 		queue_work(dev->wq, work);
1007 		/* wait for operation to complete */
1008 		flush_workqueue(dev->wq);
1009 		fput(filp);
1010 
1011 		/* read the result */
1012 		smp_rmb();
1013 		ret = dev->xfer_result;
1014 		break;
1015 	}
1016 	case MTP_SEND_EVENT:
1017 	{
1018 		struct mtp_event	event;
1019 		/* return here so we don't change dev->state below,
1020 		 * which would interfere with bulk transfer state.
1021 		 */
1022 		if (copy_from_user(&event, (void __user *)value, sizeof(event)))
1023 			ret = -EFAULT;
1024 		else
1025 			ret = mtp_send_event(dev, &event);
1026 		goto out;
1027 	}
1028 	}
1029 
1030 fail:
1031 	spin_lock_irq(&dev->lock);
1032 	if (dev->state == STATE_CANCELED)
1033 		ret = -ECANCELED;
1034 	else if (dev->state != STATE_OFFLINE)
1035 		dev->state = STATE_READY;
1036 	spin_unlock_irq(&dev->lock);
1037 out:
1038 	mtp_unlock(&dev->ioctl_excl);
1039 	DBG(dev->cdev, "ioctl returning %d\n", ret);
1040 	return ret;
1041 }
1042 
mtp_open(struct inode * ip,struct file * fp)1043 static int mtp_open(struct inode *ip, struct file *fp)
1044 {
1045 	printk(KERN_INFO "mtp_open\n");
1046 	if (mtp_lock(&_mtp_dev->open_excl))
1047 		return -EBUSY;
1048 
1049 	/* clear any error condition */
1050 	if (_mtp_dev->state != STATE_OFFLINE)
1051 		_mtp_dev->state = STATE_READY;
1052 
1053 	fp->private_data = _mtp_dev;
1054 	return 0;
1055 }
1056 
mtp_release(struct inode * ip,struct file * fp)1057 static int mtp_release(struct inode *ip, struct file *fp)
1058 {
1059 	printk(KERN_INFO "mtp_release\n");
1060 
1061 	mtp_unlock(&_mtp_dev->open_excl);
1062 	return 0;
1063 }
1064 
1065 /* file operations for /dev/mtp_usb */
1066 static const struct file_operations mtp_fops = {
1067 	.owner = THIS_MODULE,
1068 	.read = mtp_read,
1069 	.write = mtp_write,
1070 	.unlocked_ioctl = mtp_ioctl,
1071 	.open = mtp_open,
1072 	.release = mtp_release,
1073 };
1074 
1075 static struct miscdevice mtp_device = {
1076 	.minor = MISC_DYNAMIC_MINOR,
1077 	.name = mtp_shortname,
1078 	.fops = &mtp_fops,
1079 };
1080 
mtp_ctrlrequest(struct usb_composite_dev * cdev,const struct usb_ctrlrequest * ctrl)1081 static int mtp_ctrlrequest(struct usb_composite_dev *cdev,
1082 				const struct usb_ctrlrequest *ctrl)
1083 {
1084 	struct mtp_dev *dev = _mtp_dev;
1085 	int	value = -EOPNOTSUPP;
1086 	u16	w_index = le16_to_cpu(ctrl->wIndex);
1087 	u16	w_value = le16_to_cpu(ctrl->wValue);
1088 	u16	w_length = le16_to_cpu(ctrl->wLength);
1089 	unsigned long	flags;
1090 
1091 	VDBG(cdev, "mtp_ctrlrequest "
1092 			"%02x.%02x v%04x i%04x l%u\n",
1093 			ctrl->bRequestType, ctrl->bRequest,
1094 			w_value, w_index, w_length);
1095 
1096 	/* Handle MTP OS string */
1097 	if (ctrl->bRequestType ==
1098 			(USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE)
1099 			&& ctrl->bRequest == USB_REQ_GET_DESCRIPTOR
1100 			&& (w_value >> 8) == USB_DT_STRING
1101 			&& (w_value & 0xFF) == MTP_OS_STRING_ID) {
1102 		value = (w_length < sizeof(mtp_os_string)
1103 				? w_length : sizeof(mtp_os_string));
1104 		memcpy(cdev->req->buf, mtp_os_string, value);
1105 	} else if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
1106 		/* Handle MTP OS descriptor */
1107 		DBG(cdev, "vendor request: %d index: %d value: %d length: %d\n",
1108 			ctrl->bRequest, w_index, w_value, w_length);
1109 
1110 		if (ctrl->bRequest == 1
1111 				&& (ctrl->bRequestType & USB_DIR_IN)
1112 				&& (w_index == 4 || w_index == 5)) {
1113 			value = (w_length < sizeof(mtp_ext_config_desc) ?
1114 					w_length : sizeof(mtp_ext_config_desc));
1115 			memcpy(cdev->req->buf, &mtp_ext_config_desc, value);
1116 		}
1117 	} else if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
1118 		DBG(cdev, "class request: %d index: %d value: %d length: %d\n",
1119 			ctrl->bRequest, w_index, w_value, w_length);
1120 
1121 		if (ctrl->bRequest == MTP_REQ_CANCEL && w_index == 0
1122 				&& w_value == 0) {
1123 			DBG(cdev, "MTP_REQ_CANCEL\n");
1124 
1125 			spin_lock_irqsave(&dev->lock, flags);
1126 			if (dev->state == STATE_BUSY) {
1127 				dev->state = STATE_CANCELED;
1128 				wake_up(&dev->read_wq);
1129 				wake_up(&dev->write_wq);
1130 			}
1131 			spin_unlock_irqrestore(&dev->lock, flags);
1132 
1133 			/* We need to queue a request to read the remaining
1134 			 *  bytes, but we don't actually need to look at
1135 			 * the contents.
1136 			 */
1137 			value = w_length;
1138 		} else if (ctrl->bRequest == MTP_REQ_GET_DEVICE_STATUS
1139 				&& w_index == 0 && w_value == 0) {
1140 			struct mtp_device_status *status = cdev->req->buf;
1141 
1142 			status->wLength =
1143 				__constant_cpu_to_le16(sizeof(*status));
1144 
1145 			DBG(cdev, "MTP_REQ_GET_DEVICE_STATUS\n");
1146 			spin_lock_irqsave(&dev->lock, flags);
1147 			/* device status is "busy" until we report
1148 			 * the cancelation to userspace
1149 			 */
1150 			if (dev->state == STATE_CANCELED)
1151 				status->wCode =
1152 					__cpu_to_le16(MTP_RESPONSE_DEVICE_BUSY);
1153 			else
1154 				status->wCode =
1155 					__cpu_to_le16(MTP_RESPONSE_OK);
1156 			spin_unlock_irqrestore(&dev->lock, flags);
1157 			value = sizeof(*status);
1158 		}
1159 	}
1160 
1161 	/* respond with data transfer or status phase? */
1162 	if (value >= 0) {
1163 		int rc;
1164 
1165 		cdev->req->zero = value < w_length;
1166 		cdev->req->length = value;
1167 		rc = usb_ep_queue(cdev->gadget->ep0, cdev->req, GFP_ATOMIC);
1168 		if (rc < 0)
1169 			ERROR(cdev, "%s: response queue error\n", __func__);
1170 	}
1171 	return value;
1172 }
1173 
1174 static int
mtp_function_bind(struct usb_configuration * c,struct usb_function * f)1175 mtp_function_bind(struct usb_configuration *c, struct usb_function *f)
1176 {
1177 	struct usb_composite_dev *cdev = c->cdev;
1178 	struct mtp_dev	*dev = func_to_mtp(f);
1179 	int			id;
1180 	int			ret;
1181 	struct mtp_instance *fi_mtp;
1182 
1183 	dev->cdev = cdev;
1184 	DBG(cdev, "mtp_function_bind dev: %p\n", dev);
1185 
1186 	/* allocate interface ID(s) */
1187 	id = usb_interface_id(c, f);
1188 	if (id < 0)
1189 		return id;
1190 	mtp_interface_desc.bInterfaceNumber = id;
1191 
1192 	if (mtp_string_defs[INTERFACE_STRING_INDEX].id == 0) {
1193 		ret = usb_string_id(c->cdev);
1194 		if (ret < 0)
1195 			return ret;
1196 		mtp_string_defs[INTERFACE_STRING_INDEX].id = ret;
1197 		mtp_interface_desc.iInterface = ret;
1198 	}
1199 
1200 	fi_mtp = container_of(f->fi, struct mtp_instance, func_inst);
1201 
1202 	if (cdev->use_os_string) {
1203 		f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
1204 					GFP_KERNEL);
1205 		if (!f->os_desc_table)
1206 			return -ENOMEM;
1207 		f->os_desc_n = 1;
1208 		f->os_desc_table[0].os_desc = &fi_mtp->mtp_os_desc;
1209 	}
1210 
1211 	/* allocate endpoints */
1212 	ret = mtp_create_bulk_endpoints(dev, &mtp_fullspeed_in_desc,
1213 			&mtp_fullspeed_out_desc, &mtp_intr_desc);
1214 	if (ret)
1215 		return ret;
1216 
1217 	/* support high speed hardware */
1218 	if (gadget_is_dualspeed(c->cdev->gadget)) {
1219 		mtp_highspeed_in_desc.bEndpointAddress =
1220 			mtp_fullspeed_in_desc.bEndpointAddress;
1221 		mtp_highspeed_out_desc.bEndpointAddress =
1222 			mtp_fullspeed_out_desc.bEndpointAddress;
1223 	}
1224 	/* support super speed hardware */
1225 	if (gadget_is_superspeed(c->cdev->gadget)) {
1226 		unsigned max_burst;
1227 
1228 		/* Calculate bMaxBurst, we know packet size is 1024 */
1229 		max_burst = min_t(unsigned, MTP_BULK_BUFFER_SIZE / 1024, 15);
1230 		mtp_ss_in_desc.bEndpointAddress =
1231 			mtp_fullspeed_in_desc.bEndpointAddress;
1232 		mtp_ss_in_comp_desc.bMaxBurst = max_burst;
1233 		mtp_ss_out_desc.bEndpointAddress =
1234 			mtp_fullspeed_out_desc.bEndpointAddress;
1235 		mtp_ss_out_comp_desc.bMaxBurst = max_burst;
1236 	}
1237 
1238 	DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n",
1239 		gadget_is_superspeed(c->cdev->gadget) ? "super" :
1240 		(gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full"),
1241 		f->name, dev->ep_in->name, dev->ep_out->name);
1242 	return 0;
1243 }
1244 
1245 static void
mtp_function_unbind(struct usb_configuration * c,struct usb_function * f)1246 mtp_function_unbind(struct usb_configuration *c, struct usb_function *f)
1247 {
1248 	struct mtp_dev	*dev = func_to_mtp(f);
1249 	struct usb_request *req;
1250 	int i;
1251 
1252 	mtp_string_defs[INTERFACE_STRING_INDEX].id = 0;
1253 	while ((req = mtp_req_get(dev, &dev->tx_idle)))
1254 		mtp_request_free(req, dev->ep_in);
1255 	for (i = 0; i < RX_REQ_MAX; i++)
1256 		mtp_request_free(dev->rx_req[i], dev->ep_out);
1257 	while ((req = mtp_req_get(dev, &dev->intr_idle)))
1258 		mtp_request_free(req, dev->ep_intr);
1259 	dev->state = STATE_OFFLINE;
1260 	kfree(f->os_desc_table);
1261 	f->os_desc_n = 0;
1262 }
1263 
mtp_function_set_alt(struct usb_function * f,unsigned intf,unsigned alt)1264 static int mtp_function_set_alt(struct usb_function *f,
1265 		unsigned intf, unsigned alt)
1266 {
1267 	struct mtp_dev	*dev = func_to_mtp(f);
1268 	struct usb_composite_dev *cdev = f->config->cdev;
1269 	int ret;
1270 
1271 	DBG(cdev, "mtp_function_set_alt intf: %d alt: %d\n", intf, alt);
1272 
1273 	ret = config_ep_by_speed(cdev->gadget, f, dev->ep_in);
1274 	if (ret)
1275 		return ret;
1276 
1277 	ret = usb_ep_enable(dev->ep_in);
1278 	if (ret)
1279 		return ret;
1280 
1281 	ret = config_ep_by_speed(cdev->gadget, f, dev->ep_out);
1282 	if (ret)
1283 		return ret;
1284 
1285 	ret = usb_ep_enable(dev->ep_out);
1286 	if (ret) {
1287 		usb_ep_disable(dev->ep_in);
1288 		return ret;
1289 	}
1290 
1291 	ret = config_ep_by_speed(cdev->gadget, f, dev->ep_intr);
1292 	if (ret)
1293 		return ret;
1294 
1295 	ret = usb_ep_enable(dev->ep_intr);
1296 	if (ret) {
1297 		usb_ep_disable(dev->ep_out);
1298 		usb_ep_disable(dev->ep_in);
1299 		return ret;
1300 	}
1301 	dev->state = STATE_READY;
1302 
1303 	/* readers may be blocked waiting for us to go online */
1304 	wake_up(&dev->read_wq);
1305 	return 0;
1306 }
1307 
mtp_function_disable(struct usb_function * f)1308 static void mtp_function_disable(struct usb_function *f)
1309 {
1310 	struct mtp_dev	*dev = func_to_mtp(f);
1311 	struct usb_composite_dev	*cdev = dev->cdev;
1312 
1313 	DBG(cdev, "mtp_function_disable\n");
1314 	dev->state = STATE_OFFLINE;
1315 	usb_ep_disable(dev->ep_in);
1316 	usb_ep_disable(dev->ep_out);
1317 	usb_ep_disable(dev->ep_intr);
1318 
1319 	/* readers may be blocked waiting for us to go online */
1320 	wake_up(&dev->read_wq);
1321 
1322 	VDBG(cdev, "%s disabled\n", dev->function.name);
1323 }
1324 
__mtp_setup(struct mtp_instance * fi_mtp)1325 static int __mtp_setup(struct mtp_instance *fi_mtp)
1326 {
1327 	struct mtp_dev *dev;
1328 	int ret;
1329 
1330 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1331 
1332 	if (fi_mtp != NULL)
1333 		fi_mtp->dev = dev;
1334 
1335 	if (!dev)
1336 		return -ENOMEM;
1337 
1338 	spin_lock_init(&dev->lock);
1339 	init_waitqueue_head(&dev->read_wq);
1340 	init_waitqueue_head(&dev->write_wq);
1341 	init_waitqueue_head(&dev->intr_wq);
1342 	atomic_set(&dev->open_excl, 0);
1343 	atomic_set(&dev->ioctl_excl, 0);
1344 	INIT_LIST_HEAD(&dev->tx_idle);
1345 	INIT_LIST_HEAD(&dev->intr_idle);
1346 
1347 	dev->wq = create_singlethread_workqueue("f_mtp");
1348 	if (!dev->wq) {
1349 		ret = -ENOMEM;
1350 		goto err1;
1351 	}
1352 	INIT_WORK(&dev->send_file_work, send_file_work);
1353 	INIT_WORK(&dev->receive_file_work, receive_file_work);
1354 
1355 	_mtp_dev = dev;
1356 
1357 	ret = misc_register(&mtp_device);
1358 	if (ret)
1359 		goto err2;
1360 
1361 	return 0;
1362 
1363 err2:
1364 	destroy_workqueue(dev->wq);
1365 err1:
1366 	_mtp_dev = NULL;
1367 	kfree(dev);
1368 	printk(KERN_ERR "mtp gadget driver failed to initialize\n");
1369 	return ret;
1370 }
1371 
mtp_setup_configfs(struct mtp_instance * fi_mtp)1372 static int mtp_setup_configfs(struct mtp_instance *fi_mtp)
1373 {
1374 	return __mtp_setup(fi_mtp);
1375 }
1376 
1377 
mtp_cleanup(void)1378 static void mtp_cleanup(void)
1379 {
1380 	struct mtp_dev *dev = _mtp_dev;
1381 
1382 	if (!dev)
1383 		return;
1384 
1385 	misc_deregister(&mtp_device);
1386 	destroy_workqueue(dev->wq);
1387 	_mtp_dev = NULL;
1388 	kfree(dev);
1389 }
1390 
to_mtp_instance(struct config_item * item)1391 static struct mtp_instance *to_mtp_instance(struct config_item *item)
1392 {
1393 	return container_of(to_config_group(item), struct mtp_instance,
1394 		func_inst.group);
1395 }
1396 
mtp_attr_release(struct config_item * item)1397 static void mtp_attr_release(struct config_item *item)
1398 {
1399 	struct mtp_instance *fi_mtp = to_mtp_instance(item);
1400 
1401 	usb_put_function_instance(&fi_mtp->func_inst);
1402 }
1403 
1404 static struct configfs_item_operations mtp_item_ops = {
1405 	.release        = mtp_attr_release,
1406 };
1407 
1408 static struct config_item_type mtp_func_type = {
1409 	.ct_item_ops    = &mtp_item_ops,
1410 	.ct_owner       = THIS_MODULE,
1411 };
1412 
1413 
to_fi_mtp(struct usb_function_instance * fi)1414 static struct mtp_instance *to_fi_mtp(struct usb_function_instance *fi)
1415 {
1416 	return container_of(fi, struct mtp_instance, func_inst);
1417 }
1418 
mtp_set_inst_name(struct usb_function_instance * fi,const char * name)1419 static int mtp_set_inst_name(struct usb_function_instance *fi, const char *name)
1420 {
1421 	struct mtp_instance *fi_mtp;
1422 	char *ptr;
1423 	int name_len;
1424 
1425 	name_len = strlen(name) + 1;
1426 	if (name_len > MAX_INST_NAME_LEN)
1427 		return -ENAMETOOLONG;
1428 
1429 	ptr = kstrndup(name, name_len, GFP_KERNEL);
1430 	if (!ptr)
1431 		return -ENOMEM;
1432 
1433 	fi_mtp = to_fi_mtp(fi);
1434 	fi_mtp->name = ptr;
1435 
1436 	return 0;
1437 }
1438 
mtp_free_inst(struct usb_function_instance * fi)1439 static void mtp_free_inst(struct usb_function_instance *fi)
1440 {
1441 	struct mtp_instance *fi_mtp;
1442 
1443 	fi_mtp = to_fi_mtp(fi);
1444 	kfree(fi_mtp->name);
1445 	mtp_cleanup();
1446 	kfree(fi_mtp->mtp_os_desc.group.default_groups);
1447 	kfree(fi_mtp);
1448 }
1449 
alloc_inst_mtp_ptp(bool mtp_config)1450 struct usb_function_instance *alloc_inst_mtp_ptp(bool mtp_config)
1451 {
1452 	struct mtp_instance *fi_mtp;
1453 	int ret = 0;
1454 	struct usb_os_desc *descs[1];
1455 	char *names[1];
1456 
1457 	fi_mtp = kzalloc(sizeof(*fi_mtp), GFP_KERNEL);
1458 	if (!fi_mtp)
1459 		return ERR_PTR(-ENOMEM);
1460 	fi_mtp->func_inst.set_inst_name = mtp_set_inst_name;
1461 	fi_mtp->func_inst.free_func_inst = mtp_free_inst;
1462 
1463 	fi_mtp->mtp_os_desc.ext_compat_id = fi_mtp->mtp_ext_compat_id;
1464 	INIT_LIST_HEAD(&fi_mtp->mtp_os_desc.ext_prop);
1465 	descs[0] = &fi_mtp->mtp_os_desc;
1466 	names[0] = "MTP";
1467 	usb_os_desc_prepare_interf_dir(&fi_mtp->func_inst.group, 1,
1468 					descs, names, THIS_MODULE);
1469 
1470 	if (mtp_config) {
1471 		ret = mtp_setup_configfs(fi_mtp);
1472 		if (ret) {
1473 			kfree(fi_mtp);
1474 			pr_err("Error setting MTP\n");
1475 			return ERR_PTR(ret);
1476 		}
1477 	} else
1478 		fi_mtp->dev = _mtp_dev;
1479 
1480 	config_group_init_type_name(&fi_mtp->func_inst.group,
1481 					"", &mtp_func_type);
1482 
1483 	return  &fi_mtp->func_inst;
1484 }
1485 EXPORT_SYMBOL_GPL(alloc_inst_mtp_ptp);
1486 
mtp_alloc_inst(void)1487 static struct usb_function_instance *mtp_alloc_inst(void)
1488 {
1489 		return alloc_inst_mtp_ptp(true);
1490 }
1491 
mtp_ctrlreq_configfs(struct usb_function * f,const struct usb_ctrlrequest * ctrl)1492 static int mtp_ctrlreq_configfs(struct usb_function *f,
1493 				const struct usb_ctrlrequest *ctrl)
1494 {
1495 	return mtp_ctrlrequest(f->config->cdev, ctrl);
1496 }
1497 
mtp_free(struct usb_function * f)1498 static void mtp_free(struct usb_function *f)
1499 {
1500 	/*NO-OP: no function specific resource allocation in mtp_alloc*/
1501 }
1502 
function_alloc_mtp_ptp(struct usb_function_instance * fi,bool mtp_config)1503 struct usb_function *function_alloc_mtp_ptp(struct usb_function_instance *fi,
1504 					bool mtp_config)
1505 {
1506 	struct mtp_instance *fi_mtp = to_fi_mtp(fi);
1507 	struct mtp_dev *dev;
1508 
1509 	/*
1510 	 * PTP piggybacks on MTP function so make sure we have
1511 	 * created MTP function before we associate this PTP
1512 	 * function with a gadget configuration.
1513 	 */
1514 	if (fi_mtp->dev == NULL) {
1515 		pr_err("Error: Create MTP function before linking"
1516 				" PTP function with a gadget configuration\n");
1517 		pr_err("\t1: Delete existing PTP function if any\n");
1518 		pr_err("\t2: Create MTP function\n");
1519 		pr_err("\t3: Create and symlink PTP function"
1520 				" with a gadget configuration\n");
1521 		return ERR_PTR(-EINVAL); /* Invalid Configuration */
1522 	}
1523 
1524 	dev = fi_mtp->dev;
1525 	dev->function.name = DRIVER_NAME;
1526 	dev->function.strings = mtp_strings;
1527 	if (mtp_config) {
1528 		dev->function.fs_descriptors = fs_mtp_descs;
1529 		dev->function.hs_descriptors = hs_mtp_descs;
1530 		dev->function.ss_descriptors = ss_mtp_descs;
1531 	} else {
1532 		dev->function.fs_descriptors = fs_ptp_descs;
1533 		dev->function.hs_descriptors = hs_ptp_descs;
1534 		dev->function.ss_descriptors = ss_ptp_descs;
1535 	}
1536 	dev->function.bind = mtp_function_bind;
1537 	dev->function.unbind = mtp_function_unbind;
1538 	dev->function.set_alt = mtp_function_set_alt;
1539 	dev->function.disable = mtp_function_disable;
1540 	dev->function.setup = mtp_ctrlreq_configfs;
1541 	dev->function.free_func = mtp_free;
1542 
1543 	return &dev->function;
1544 }
1545 EXPORT_SYMBOL_GPL(function_alloc_mtp_ptp);
1546 
mtp_alloc(struct usb_function_instance * fi)1547 static struct usb_function *mtp_alloc(struct usb_function_instance *fi)
1548 {
1549 	return function_alloc_mtp_ptp(fi, true);
1550 }
1551 
1552 DECLARE_USB_FUNCTION_INIT(mtp, mtp_alloc_inst, mtp_alloc);
1553 MODULE_LICENSE("GPL");
1554