2 * Gadget Driver for Samsung SDB (based on Android ADB)
4 * Copyright (C) 2008 Google, Inc.
5 * Author: Mike Lockwood <lockwood@android.com>
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.
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.
19 /* #define VERBOSE_DEBUG */
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/poll.h>
24 #include <linux/delay.h>
25 #include <linux/sched.h>
26 #include <linux/wait.h>
27 #include <linux/err.h>
28 #include <linux/interrupt.h>
30 #include <linux/types.h>
31 #include <linux/device.h>
32 #include <linux/miscdevice.h>
34 #define SDB_BULK_BUFFER_SIZE 4096
36 /* number of tx requests to allocate */
37 #define SDB_TX_REQ_MAX 4
39 static const char sdb_shortname[] = "samsung_sdb";
41 static DEFINE_MUTEX(sdb_lock);
44 struct usb_endpoint_descriptor *in;
45 struct usb_endpoint_descriptor *out;
49 struct usb_function function;
52 struct sdb_ep_descs fs;
53 struct sdb_ep_descs hs;
56 struct usb_ep *ep_out;
58 struct list_head bulk_in_q;
62 struct f_sdb *sdb_func;
72 struct list_head *tx_idle;
74 wait_queue_head_t read_wq;
75 wait_queue_head_t write_wq;
77 struct usb_request *rx_req;
81 static struct usb_interface_descriptor sdb_interface_desc = {
82 .bLength = USB_DT_INTERFACE_SIZE,
83 .bDescriptorType = USB_DT_INTERFACE,
84 /* .bInterfaceNumber = DYNAMIC */
86 .bInterfaceClass = 0xFF,
87 .bInterfaceSubClass = 0x20,
88 .bInterfaceProtocol = 0x02,
89 /* .iInterface = DYNAMIC */
92 static struct usb_endpoint_descriptor sdb_fullspeed_in_desc = {
93 .bLength = USB_DT_ENDPOINT_SIZE,
94 .bDescriptorType = USB_DT_ENDPOINT,
95 .bEndpointAddress = USB_DIR_IN,
96 .bmAttributes = USB_ENDPOINT_XFER_BULK,
97 /* .wMaxPacketSize set by autoconfiguration */
100 static struct usb_endpoint_descriptor sdb_fullspeed_out_desc = {
101 .bLength = USB_DT_ENDPOINT_SIZE,
102 .bDescriptorType = USB_DT_ENDPOINT,
103 .bEndpointAddress = USB_DIR_OUT,
104 .bmAttributes = USB_ENDPOINT_XFER_BULK,
105 /* .wMaxPacketSize set by autoconfiguration */
108 static struct usb_descriptor_header *fs_sdb_descs[] = {
109 (struct usb_descriptor_header *) &sdb_interface_desc,
110 (struct usb_descriptor_header *) &sdb_fullspeed_in_desc,
111 (struct usb_descriptor_header *) &sdb_fullspeed_out_desc,
115 static struct usb_endpoint_descriptor sdb_highspeed_in_desc = {
116 .bLength = USB_DT_ENDPOINT_SIZE,
117 .bDescriptorType = USB_DT_ENDPOINT,
118 /* bEndpointAddress copied from sdb_fullspeed_in_desc
119 during sdb_function_bind() */
120 .bmAttributes = USB_ENDPOINT_XFER_BULK,
121 .wMaxPacketSize = cpu_to_le16(512),
124 static struct usb_endpoint_descriptor sdb_highspeed_out_desc = {
125 .bLength = USB_DT_ENDPOINT_SIZE,
126 .bDescriptorType = USB_DT_ENDPOINT,
127 /* bEndpointAddress copied from sdb_fullspeed_in_desc
128 during sdb_function_bind() */
129 .bmAttributes = USB_ENDPOINT_XFER_BULK,
130 .wMaxPacketSize = cpu_to_le16(512),
133 static struct usb_descriptor_header *hs_sdb_descs[] = {
134 (struct usb_descriptor_header *) &sdb_interface_desc,
135 (struct usb_descriptor_header *) &sdb_highspeed_in_desc,
136 (struct usb_descriptor_header *) &sdb_highspeed_out_desc,
140 /* string descriptors: */
144 /* static strings, in UTF-8 */
145 static struct usb_string sdb_string_defs[] = {
146 [F_SDB_IDX].s = "Samsung SDB",
147 { /* ZEROES END LIST */ },
150 static struct usb_gadget_strings sdb_string_table = {
151 .language = 0x0409, /* en-us */
152 .strings = sdb_string_defs,
155 static struct usb_gadget_strings *sdb_strings[] = {
160 /* temporary variable used between sdb_open() and sdb_gadget_bind() */
161 static struct sdb_dev *_sdb_dev;
163 static inline struct f_sdb *func_to_sdb(struct usb_function *f)
165 return container_of(f, struct f_sdb, function);
168 static struct usb_request *sdb_request_new(struct usb_ep *ep, int buffer_size)
170 struct usb_request *req = usb_ep_alloc_request(ep, GFP_KERNEL);
174 /* now allocate buffers for the requests */
175 req->buf = kmalloc(buffer_size, GFP_KERNEL);
177 usb_ep_free_request(ep, req);
184 static void sdb_request_free(struct usb_request *req, struct usb_ep *ep)
188 usb_ep_free_request(ep, req);
192 static inline int _sdb_lock(atomic_t *excl)
194 if (atomic_inc_return(excl) == 1) {
202 static inline void _sdb_unlock(atomic_t *excl)
207 /* add a request to the tail of a list */
208 static void sdb_req_put(struct sdb_dev *dev, struct list_head *head,
209 struct usb_request *req)
216 spin_lock_irqsave(&dev->lock, flags);
218 list_add_tail(&req->list, head);
219 spin_unlock_irqrestore(&dev->lock, flags);
222 /* remove a request from the head of a list */
223 static struct usb_request *sdb_req_get(struct sdb_dev *dev,
224 struct list_head *head)
227 struct usb_request *req;
232 spin_lock_irqsave(&dev->lock, flags);
236 if (list_empty(head)) {
239 req = list_first_entry(head, struct usb_request, list);
240 list_del(&req->list);
243 spin_unlock_irqrestore(&dev->lock, flags);
247 static void sdb_complete_in(struct usb_ep *ep, struct usb_request *req)
249 struct sdb_dev *dev = _sdb_dev;
250 struct f_sdb *sdb_func = ep->driver_data;
252 if (req->status != 0)
255 sdb_req_put(dev, &sdb_func->bulk_in_q, req);
256 wake_up(&dev->write_wq);
259 static void sdb_complete_out(struct usb_ep *ep, struct usb_request *req)
261 struct sdb_dev *dev = _sdb_dev;
264 if (req->status != 0)
267 wake_up(&dev->read_wq);
270 static int sdb_create_bulk_endpoints(struct f_sdb *sdb_func,
271 struct usb_endpoint_descriptor *in_desc,
272 struct usb_endpoint_descriptor *out_desc)
274 struct usb_composite_dev *cdev = sdb_func->function.config->cdev;
275 struct usb_request *req;
276 struct sdb_dev *dev = _sdb_dev;
280 DBG(cdev, "sdb_create_bulk_endpoints dev: %p\n", dev);
282 ep = usb_ep_autoconfig(cdev->gadget, in_desc);
284 ERROR(cdev, "usb_ep_autoconfig for ep_in failed\n");
287 DBG(cdev, "usb_ep_autoconfig for ep_in got %s\n", ep->name);
288 ep->driver_data = cdev; /* claim the endpoint */
289 sdb_func->ep_in = ep;
291 ep = usb_ep_autoconfig(cdev->gadget, out_desc);
293 ERROR(cdev, "usb_ep_autoconfig for ep_out failed\n");
296 DBG(cdev, "usb_ep_autoconfig for sdb ep_out got %s\n", ep->name);
297 ep->driver_data = cdev; /* claim the endpoint */
298 sdb_func->ep_out = ep;
300 /* now allocate requests for our endpoints */
301 req = sdb_request_new(sdb_func->ep_out, SDB_BULK_BUFFER_SIZE);
304 req->complete = sdb_complete_out;
307 for (i = 0; i < SDB_TX_REQ_MAX; i++) {
308 req = sdb_request_new(sdb_func->ep_in, SDB_BULK_BUFFER_SIZE);
311 req->complete = sdb_complete_in;
312 sdb_req_put(dev, &sdb_func->bulk_in_q, req);
318 while (!!(req = sdb_req_get(dev, &sdb_func->bulk_in_q)))
319 sdb_request_free(req, sdb_func->ep_in);
321 sdb_request_free(dev->rx_req, sdb_func->ep_out);
325 sdb_func->ep_in->driver_data = NULL;
326 if (sdb_func->ep_out)
327 sdb_func->ep_out->driver_data = NULL;
329 printk(KERN_ERR "sdb_bind() could not allocate requests\n");
333 static ssize_t sdb_read(struct file *fp, char __user *buf,
334 size_t count, loff_t *pos)
336 struct sdb_dev *dev = fp->private_data;
340 if (count > SDB_BULK_BUFFER_SIZE)
343 if (_sdb_lock(&dev->read_excl))
346 /* we will block until we're online */
347 while (!(dev->online || dev->error)) {
348 ret = wait_event_interruptible(dev->read_wq,
349 (dev->online || dev->error));
351 _sdb_unlock(&dev->read_excl);
360 /* queue a request */
361 mutex_lock(&sdb_lock);
362 if (!dev->sdb_func || !dev->rx_req)
366 dev->rx_req->length = count;
368 ret = usb_ep_queue(dev->sdb_func->ep_out,
369 dev->rx_req, GFP_ATOMIC);
371 mutex_unlock(&sdb_lock);
379 /* wait for a request to complete */
380 ret = wait_event_interruptible(dev->read_wq, dev->rx_done);
387 mutex_lock(&sdb_lock);
388 if (!dev->sdb_func || !dev->rx_req)
390 else if (dev->rx_req->actual == 0)
391 /* If we got a 0-len packet, throw it back and try again. */
394 xfer = (dev->rx_req->actual < count)
395 ? dev->rx_req->actual : count;
396 if (copy_to_user(buf, dev->rx_req->buf, xfer))
399 mutex_unlock(&sdb_lock);
404 _sdb_unlock(&dev->read_excl);
408 static ssize_t sdb_write(struct file *fp, const char __user *buf,
409 size_t count, loff_t *pos)
411 struct sdb_dev *dev = fp->private_data;
412 struct usb_request *req = 0;
416 if (_sdb_lock(&dev->write_excl))
425 /* get an idle tx request to use */
427 ret = wait_event_interruptible(dev->write_wq,
428 (!!(req = sdb_req_get(dev, dev->tx_idle))
437 if (count > SDB_BULK_BUFFER_SIZE)
438 xfer = SDB_BULK_BUFFER_SIZE;
442 mutex_lock(&sdb_lock);
443 if (!dev->sdb_func) {
444 mutex_unlock(&sdb_lock);
447 } else if (copy_from_user(req->buf, buf, xfer)) {
448 mutex_unlock(&sdb_lock);
454 ret = usb_ep_queue(dev->sdb_func->ep_in,
456 mutex_unlock(&sdb_lock);
467 /* zero this so we don't try to free it on error exit */
473 sdb_req_put(dev, dev->tx_idle, req);
475 _sdb_unlock(&dev->write_excl);
479 static int sdb_open(struct inode *ip, struct file *fp)
481 printk(KERN_INFO "sdb_open\n");
482 if (_sdb_lock(&_sdb_dev->open_excl))
485 fp->private_data = _sdb_dev;
487 /* clear the error latch */
493 static int sdb_release(struct inode *ip, struct file *fp)
495 printk(KERN_INFO "sdb_release\n");
497 if (_sdb_dev != NULL)
498 _sdb_unlock(&_sdb_dev->open_excl);
503 /* file operations for SDB device /dev/samsung_sdb */
504 static const struct file_operations sdb_fops = {
505 .owner = THIS_MODULE,
509 .release = sdb_release,
512 static struct miscdevice sdb_device = {
513 .minor = MISC_DYNAMIC_MINOR,
514 .name = sdb_shortname,
519 sdb_function_bind(struct usb_configuration *c, struct usb_function *f)
521 struct usb_composite_dev *cdev = c->cdev;
522 struct f_sdb *sdb_func = func_to_sdb(f);
526 DBG(cdev, "sdb_function_bind sdb_func: %p\n", sdb_func);
528 /* allocate interface ID(s) */
529 id = usb_interface_id(c, f);
533 sdb_func->inf_id = id;
534 sdb_interface_desc.bInterfaceNumber = id;
536 /* allocate endpoints */
537 ret = sdb_create_bulk_endpoints(sdb_func, &sdb_fullspeed_in_desc,
538 &sdb_fullspeed_out_desc);
542 f->fs_descriptors = usb_copy_descriptors(fs_sdb_descs);
543 if (!f->fs_descriptors)
544 goto desc_alloc_fail;
546 /* support high speed hardware */
547 if (gadget_is_dualspeed(cdev->gadget)) {
548 sdb_highspeed_in_desc.bEndpointAddress =
549 sdb_fullspeed_in_desc.bEndpointAddress;
550 sdb_highspeed_out_desc.bEndpointAddress =
551 sdb_fullspeed_out_desc.bEndpointAddress;
553 f->hs_descriptors = usb_copy_descriptors(hs_sdb_descs);
554 if (!f->hs_descriptors)
555 goto desc_alloc_fail;
561 if (f->fs_descriptors)
562 usb_free_descriptors(f->fs_descriptors);
568 sdb_function_unbind(struct usb_configuration *c, struct usb_function *f)
570 struct sdb_dev *dev = _sdb_dev;
571 struct f_sdb *sdb_func = func_to_sdb(f);
572 struct usb_request *req;
577 if (gadget_is_dualspeed(c->cdev->gadget))
578 usb_free_descriptors(f->hs_descriptors);
579 usb_free_descriptors(f->fs_descriptors);
581 mutex_lock(&sdb_lock);
583 while (!!(req = sdb_req_get(dev, &sdb_func->bulk_in_q)))
584 sdb_request_free(req, sdb_func->ep_in);
586 sdb_request_free(dev->rx_req, sdb_func->ep_out);
589 dev->sdb_func = NULL;
592 mutex_unlock(&sdb_lock);
594 wake_up(&dev->read_wq);
595 wake_up(&dev->write_wq);
598 static int sdb_function_set_alt(struct usb_function *f,
599 unsigned intf, unsigned alt)
601 struct f_sdb *sdb_func = func_to_sdb(f);
602 struct usb_composite_dev *cdev = f->config->cdev;
603 struct sdb_dev *dev = _sdb_dev;
606 if (sdb_func->inf_id != intf) {
607 printk(KERN_ERR "sdb_function_set_alt error wrong intf:%d alt:%d\n",
612 if (sdb_func->ep_in->driver_data)
613 usb_ep_disable(sdb_func->ep_in);
614 else if (config_ep_by_speed(cdev->gadget, f, sdb_func->ep_in))
617 ret = usb_ep_enable(sdb_func->ep_in);
619 printk(KERN_ERR "error, usb_ep_enable for sdb ep_in\n");
622 sdb_func->ep_in->driver_data = sdb_func;
624 if (sdb_func->ep_out->driver_data)
625 usb_ep_disable(sdb_func->ep_out);
626 else if (config_ep_by_speed(cdev->gadget, f, sdb_func->ep_out)) {
627 usb_ep_disable(sdb_func->ep_in);
628 sdb_func->ep_in->driver_data = NULL;
632 ret = usb_ep_enable(sdb_func->ep_out);
634 usb_ep_disable(sdb_func->ep_in);
635 sdb_func->ep_in->driver_data = NULL;
636 printk(KERN_ERR "error, usb_ep_enable for sdb ep_out\n");
639 sdb_func->ep_out->driver_data = sdb_func;
641 dev->tx_idle = &sdb_func->bulk_in_q;
642 dev->sdb_func = sdb_func;
645 /* readers may be blocked waiting for us to go online */
646 wake_up(&dev->read_wq);
650 static void sdb_function_disable(struct usb_function *f)
652 struct sdb_dev *dev = _sdb_dev;
653 struct f_sdb *sdb_func = func_to_sdb(f);
658 spin_lock(&dev->lock);
660 spin_unlock(&dev->lock);
662 usb_ep_disable(sdb_func->ep_in);
663 sdb_func->ep_in->driver_data = NULL;
665 usb_ep_disable(sdb_func->ep_out);
666 sdb_func->ep_out->driver_data = NULL;
668 /* readers may be blocked waiting for us to go online */
669 wake_up(&dev->read_wq);
670 wake_up(&dev->write_wq);
673 static int sdb_setup(struct usb_composite_dev *cdev)
678 printk(KERN_INFO "sdb_bind_config\n");
680 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
684 if (sdb_string_defs[F_SDB_IDX].id == 0) {
685 ret = usb_string_id(cdev);
690 sdb_string_defs[F_SDB_IDX].id = ret;
691 sdb_interface_desc.iInterface = ret;
694 spin_lock_init(&dev->lock);
696 init_waitqueue_head(&dev->read_wq);
697 init_waitqueue_head(&dev->write_wq);
699 atomic_set(&dev->open_excl, 0);
700 atomic_set(&dev->read_excl, 0);
701 atomic_set(&dev->write_excl, 0);
704 /* _sdb_dev must be set before calling usb_gadget_register_driver */
707 ret = misc_register(&sdb_device);
716 printk(KERN_ERR "sdb gadget driver failed to initialize\n");
720 static int sdb_bind_config(struct usb_configuration *c)
723 struct f_sdb *sdb_func;
726 printk(KERN_ERR "Error There is no _sdb_dev!!\n");
730 sdb_func = kzalloc(sizeof(*sdb_func), GFP_KERNEL);
732 printk(KERN_ERR "sdb_func memory alloc failed !!!\n");
736 INIT_LIST_HEAD(&sdb_func->bulk_in_q);
738 sdb_func->function.name = "sdb";
739 sdb_func->function.strings = sdb_strings;
740 sdb_func->function.bind = sdb_function_bind;
741 sdb_func->function.unbind = sdb_function_unbind;
742 sdb_func->function.set_alt = sdb_function_set_alt;
743 sdb_func->function.disable = sdb_function_disable;
745 ret = usb_add_function(c, &sdb_func->function);
747 printk(KERN_ERR "Error in usb_add_function failed for sdb\n");
752 static void sdb_cleanup(void)
754 struct sdb_dev *dev = _sdb_dev;
756 misc_deregister(&sdb_device);