1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Native support for the I/O-Warrior USB devices
4 *
5 * Copyright (c) 2003-2005, 2020 Code Mercenaries GmbH
6 * written by Christian Lucht <lucht@codemercs.com> and
7 * Christoph Jung <jung@codemercs.com>
8 *
9 * based on
10
11 * usb-skeleton.c by Greg Kroah-Hartman <greg@kroah.com>
12 * brlvger.c by Stephane Dalton <sdalton@videotron.ca>
13 * and Stephane Doyon <s.doyon@videotron.ca>
14 *
15 * Released under the GPLv2.
16 */
17
18 #include <linux/module.h>
19 #include <linux/usb.h>
20 #include <linux/slab.h>
21 #include <linux/sched.h>
22 #include <linux/mutex.h>
23 #include <linux/poll.h>
24 #include <linux/hid.h>
25 #include <linux/usb/iowarrior.h>
26
27 #define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
28 #define DRIVER_DESC "USB IO-Warrior driver"
29
30 #define USB_VENDOR_ID_CODEMERCS 1984
31 /* low speed iowarrior */
32 #define USB_DEVICE_ID_CODEMERCS_IOW40 0x1500
33 #define USB_DEVICE_ID_CODEMERCS_IOW24 0x1501
34 #define USB_DEVICE_ID_CODEMERCS_IOWPV1 0x1511
35 #define USB_DEVICE_ID_CODEMERCS_IOWPV2 0x1512
36 /* full speed iowarrior */
37 #define USB_DEVICE_ID_CODEMERCS_IOW56 0x1503
38 /* fuller speed iowarrior */
39 #define USB_DEVICE_ID_CODEMERCS_IOW28 0x1504
40 #define USB_DEVICE_ID_CODEMERCS_IOW28L 0x1505
41 #define USB_DEVICE_ID_CODEMERCS_IOW100 0x1506
42
43 /* OEMed devices */
44 #define USB_DEVICE_ID_CODEMERCS_IOW24SAG 0x158a
45 #define USB_DEVICE_ID_CODEMERCS_IOW56AM 0x158b
46
47 /* Get a minor range for your devices from the usb maintainer */
48 #ifdef CONFIG_USB_DYNAMIC_MINORS
49 #define IOWARRIOR_MINOR_BASE 0
50 #else
51 #define IOWARRIOR_MINOR_BASE 208 // SKELETON_MINOR_BASE 192 + 16, not official yet
52 #endif
53
54 /* interrupt input queue size */
55 #define MAX_INTERRUPT_BUFFER 16
56 /*
57 maximum number of urbs that are submitted for writes at the same time,
58 this applies to the IOWarrior56 only!
59 IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
60 */
61 #define MAX_WRITES_IN_FLIGHT 4
62
63 MODULE_AUTHOR(DRIVER_AUTHOR);
64 MODULE_DESCRIPTION(DRIVER_DESC);
65 MODULE_LICENSE("GPL");
66
67 static struct usb_driver iowarrior_driver;
68
69 /*--------------*/
70 /* data */
71 /*--------------*/
72
73 /* Structure to hold all of our device specific stuff */
74 struct iowarrior {
75 struct kref kref;
76 struct mutex mutex; /* locks this structure */
77 struct usb_device *udev; /* save off the usb device pointer */
78 struct usb_interface *interface; /* the interface for this device */
79 struct usb_endpoint_descriptor *int_out_endpoint; /* endpoint for reading (needed for IOW56 only) */
80 struct usb_endpoint_descriptor *int_in_endpoint; /* endpoint for reading */
81 struct urb *int_in_urb; /* the urb for reading data */
82 unsigned char *int_in_buffer; /* buffer for data to be read */
83 unsigned char serial_number; /* to detect lost packages */
84 unsigned char *read_queue; /* size is MAX_INTERRUPT_BUFFER * packet size */
85 wait_queue_head_t read_wait;
86 wait_queue_head_t write_wait; /* wait-queue for writing to the device */
87 atomic_t write_busy; /* number of write-urbs submitted */
88 atomic_t read_idx;
89 atomic_t intr_idx;
90 atomic_t overflow_flag; /* signals an index 'rollover' */
91 int present; /* this is 1 as long as the device is connected */
92 int opened; /* this is 1 if the device is currently open */
93 char chip_serial[9]; /* the serial number string of the chip connected */
94 int report_size; /* number of bytes in a report */
95 u16 product_id;
96 struct usb_anchor submitted;
97 };
98
99 /*--------------*/
100 /* globals */
101 /*--------------*/
102
103 //#if 0
usb_get_report(struct usb_device * dev,struct usb_host_interface * inter,unsigned char type,unsigned char id,void * buf,int size)104 static int usb_get_report(struct usb_device *dev,
105 struct usb_host_interface *inter, unsigned char type,
106 unsigned char id, void *buf, int size)
107 {
108 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
109 HID_REQ_GET_REPORT,
110 USB_DIR_IN | USB_TYPE_CLASS |
111 USB_RECIP_INTERFACE, (type << 8) + id,
112 inter->desc.bInterfaceNumber, buf, size,
113 USB_CTRL_GET_TIMEOUT);
114 }
115 //#endif
116
usb_set_report(struct usb_interface * intf,unsigned char type,unsigned char id,void * buf,int size)117 static int usb_set_report(struct usb_interface *intf, unsigned char type,
118 unsigned char id, void *buf, int size)
119 {
120 return usb_control_msg(interface_to_usbdev(intf),
121 usb_sndctrlpipe(interface_to_usbdev(intf), 0),
122 HID_REQ_SET_REPORT,
123 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
124 (type << 8) + id,
125 intf->cur_altsetting->desc.bInterfaceNumber, buf,
126 size, 1000);
127 }
128
129 /*---------------------*/
130 /* driver registration */
131 /*---------------------*/
132 /* table of devices that work with this driver */
133 static const struct usb_device_id iowarrior_ids[] = {
134 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
135 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
136 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
137 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
138 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
139 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)},
140 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)},
141 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)},
142 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)},
143 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)},
144 {} /* Terminating entry */
145 };
146 MODULE_DEVICE_TABLE(usb, iowarrior_ids);
147
148 /*
149 * USB callback handler for reading data
150 */
iowarrior_callback(struct urb * urb)151 static void iowarrior_callback(struct urb *urb)
152 {
153 struct iowarrior *dev = urb->context;
154 int intr_idx;
155 int read_idx;
156 int aux_idx;
157 int offset;
158 int status = urb->status;
159 int retval;
160
161 switch (status) {
162 case 0:
163 /* success */
164 break;
165 case -ECONNRESET:
166 case -ENOENT:
167 case -ESHUTDOWN:
168 return;
169 default:
170 goto exit;
171 }
172
173 intr_idx = atomic_read(&dev->intr_idx);
174 /* aux_idx become previous intr_idx */
175 aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
176 read_idx = atomic_read(&dev->read_idx);
177
178 /* queue is not empty and it's interface 0 */
179 if ((intr_idx != read_idx)
180 && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
181 /* + 1 for serial number */
182 offset = aux_idx * (dev->report_size + 1);
183 if (!memcmp
184 (dev->read_queue + offset, urb->transfer_buffer,
185 dev->report_size)) {
186 /* equal values on interface 0 will be ignored */
187 goto exit;
188 }
189 }
190
191 /* aux_idx become next intr_idx */
192 aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
193 if (read_idx == aux_idx) {
194 /* queue full, dropping oldest input */
195 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
196 atomic_set(&dev->read_idx, read_idx);
197 atomic_set(&dev->overflow_flag, 1);
198 }
199
200 /* +1 for serial number */
201 offset = intr_idx * (dev->report_size + 1);
202 memcpy(dev->read_queue + offset, urb->transfer_buffer,
203 dev->report_size);
204 *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
205
206 atomic_set(&dev->intr_idx, aux_idx);
207 /* tell the blocking read about the new data */
208 wake_up_interruptible(&dev->read_wait);
209
210 exit:
211 retval = usb_submit_urb(urb, GFP_ATOMIC);
212 if (retval)
213 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n",
214 __func__, retval);
215
216 }
217
218 /*
219 * USB Callback handler for write-ops
220 */
iowarrior_write_callback(struct urb * urb)221 static void iowarrior_write_callback(struct urb *urb)
222 {
223 struct iowarrior *dev;
224 int status = urb->status;
225
226 dev = urb->context;
227 /* sync/async unlink faults aren't errors */
228 if (status &&
229 !(status == -ENOENT ||
230 status == -ECONNRESET || status == -ESHUTDOWN)) {
231 dev_dbg(&dev->interface->dev,
232 "nonzero write bulk status received: %d\n", status);
233 }
234 /* free up our allocated buffer */
235 kfree(urb->transfer_buffer);
236 /* tell a waiting writer the interrupt-out-pipe is available again */
237 atomic_dec(&dev->write_busy);
238 wake_up_interruptible(&dev->write_wait);
239 }
240
241 /*
242 * iowarrior_delete
243 */
iowarrior_delete(struct kref * kref)244 static inline void iowarrior_delete(struct kref *kref)
245 {
246 struct iowarrior *dev = container_of(kref, struct iowarrior, kref);
247
248 kfree(dev->int_in_buffer);
249 usb_free_urb(dev->int_in_urb);
250 kfree(dev->read_queue);
251 usb_put_intf(dev->interface);
252 kfree(dev);
253 }
254
255 /*---------------------*/
256 /* fops implementation */
257 /*---------------------*/
258
read_index(struct iowarrior * dev)259 static int read_index(struct iowarrior *dev)
260 {
261 int intr_idx, read_idx;
262
263 read_idx = atomic_read(&dev->read_idx);
264 intr_idx = atomic_read(&dev->intr_idx);
265
266 return (read_idx == intr_idx ? -1 : read_idx);
267 }
268
269 /*
270 * iowarrior_read
271 */
iowarrior_read(struct file * file,char __user * buffer,size_t count,loff_t * ppos)272 static ssize_t iowarrior_read(struct file *file, char __user *buffer,
273 size_t count, loff_t *ppos)
274 {
275 struct iowarrior *dev;
276 int read_idx;
277 int offset;
278 int retval;
279
280 dev = file->private_data;
281
282 if (file->f_flags & O_NONBLOCK) {
283 retval = mutex_trylock(&dev->mutex);
284 if (!retval)
285 return -EAGAIN;
286 } else {
287 retval = mutex_lock_interruptible(&dev->mutex);
288 if (retval)
289 return -ERESTARTSYS;
290 }
291
292 /* verify that the device wasn't unplugged */
293 if (!dev->present) {
294 retval = -ENODEV;
295 goto exit;
296 }
297
298 /* read count must be packet size (+ time stamp) */
299 if ((count != dev->report_size)
300 && (count != (dev->report_size + 1))) {
301 retval = -EINVAL;
302 goto exit;
303 }
304
305 /* repeat until no buffer overrun in callback handler occur */
306 do {
307 atomic_set(&dev->overflow_flag, 0);
308 if ((read_idx = read_index(dev)) == -1) {
309 /* queue empty */
310 if (file->f_flags & O_NONBLOCK) {
311 retval = -EAGAIN;
312 goto exit;
313 }
314 else {
315 //next line will return when there is either new data, or the device is unplugged
316 int r = wait_event_interruptible(dev->read_wait,
317 (!dev->present
318 || (read_idx =
319 read_index
320 (dev)) !=
321 -1));
322 if (r) {
323 //we were interrupted by a signal
324 retval = -ERESTART;
325 goto exit;
326 }
327 if (!dev->present) {
328 //The device was unplugged
329 retval = -ENODEV;
330 goto exit;
331 }
332 if (read_idx == -1) {
333 // Can this happen ???
334 retval = 0;
335 goto exit;
336 }
337 }
338 }
339
340 offset = read_idx * (dev->report_size + 1);
341 if (copy_to_user(buffer, dev->read_queue + offset, count)) {
342 retval = -EFAULT;
343 goto exit;
344 }
345 } while (atomic_read(&dev->overflow_flag));
346
347 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
348 atomic_set(&dev->read_idx, read_idx);
349 mutex_unlock(&dev->mutex);
350 return count;
351
352 exit:
353 mutex_unlock(&dev->mutex);
354 return retval;
355 }
356
357 /*
358 * iowarrior_write
359 */
iowarrior_write(struct file * file,const char __user * user_buffer,size_t count,loff_t * ppos)360 static ssize_t iowarrior_write(struct file *file,
361 const char __user *user_buffer,
362 size_t count, loff_t *ppos)
363 {
364 struct iowarrior *dev;
365 int retval;
366 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */
367 struct urb *int_out_urb = NULL;
368
369 dev = file->private_data;
370
371 retval = mutex_lock_interruptible(&dev->mutex);
372 if (retval < 0)
373 return -EINTR;
374
375 /* verify that the device wasn't unplugged */
376 if (!dev->present) {
377 retval = -ENODEV;
378 goto exit;
379 }
380 /* if count is 0 we're already done */
381 if (count == 0) {
382 retval = 0;
383 goto exit;
384 }
385 /* We only accept full reports */
386 if (count != dev->report_size) {
387 retval = -EINVAL;
388 goto exit;
389 }
390 switch (dev->product_id) {
391 case USB_DEVICE_ID_CODEMERCS_IOW24:
392 case USB_DEVICE_ID_CODEMERCS_IOW24SAG:
393 case USB_DEVICE_ID_CODEMERCS_IOWPV1:
394 case USB_DEVICE_ID_CODEMERCS_IOWPV2:
395 case USB_DEVICE_ID_CODEMERCS_IOW40:
396 /* IOW24 and IOW40 use a synchronous call */
397 buf = memdup_user(user_buffer, count);
398 if (IS_ERR(buf)) {
399 retval = PTR_ERR(buf);
400 goto exit;
401 }
402 retval = usb_set_report(dev->interface, 2, 0, buf, count);
403 kfree(buf);
404 goto exit;
405 case USB_DEVICE_ID_CODEMERCS_IOW56:
406 case USB_DEVICE_ID_CODEMERCS_IOW56AM:
407 case USB_DEVICE_ID_CODEMERCS_IOW28:
408 case USB_DEVICE_ID_CODEMERCS_IOW28L:
409 case USB_DEVICE_ID_CODEMERCS_IOW100:
410 /* The IOW56 uses asynchronous IO and more urbs */
411 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
412 /* Wait until we are below the limit for submitted urbs */
413 if (file->f_flags & O_NONBLOCK) {
414 retval = -EAGAIN;
415 goto exit;
416 } else {
417 retval = wait_event_interruptible(dev->write_wait,
418 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
419 if (retval) {
420 /* we were interrupted by a signal */
421 retval = -ERESTART;
422 goto exit;
423 }
424 if (!dev->present) {
425 /* The device was unplugged */
426 retval = -ENODEV;
427 goto exit;
428 }
429 if (!dev->opened) {
430 /* We were closed while waiting for an URB */
431 retval = -ENODEV;
432 goto exit;
433 }
434 }
435 }
436 atomic_inc(&dev->write_busy);
437 int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
438 if (!int_out_urb) {
439 retval = -ENOMEM;
440 goto error_no_urb;
441 }
442 buf = kmalloc(dev->report_size, GFP_KERNEL);
443 if (!buf) {
444 retval = -ENOMEM;
445 dev_dbg(&dev->interface->dev,
446 "Unable to allocate buffer\n");
447 goto error_no_buffer;
448 }
449 usb_fill_int_urb(int_out_urb, dev->udev,
450 usb_sndintpipe(dev->udev,
451 dev->int_out_endpoint->bEndpointAddress),
452 buf, dev->report_size,
453 iowarrior_write_callback, dev,
454 dev->int_out_endpoint->bInterval);
455 if (copy_from_user(buf, user_buffer, count)) {
456 retval = -EFAULT;
457 goto error;
458 }
459 usb_anchor_urb(int_out_urb, &dev->submitted);
460 retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
461 if (retval) {
462 dev_dbg(&dev->interface->dev,
463 "submit error %d for urb nr.%d\n",
464 retval, atomic_read(&dev->write_busy));
465 usb_unanchor_urb(int_out_urb);
466 goto error;
467 }
468 /* submit was ok */
469 retval = count;
470 usb_free_urb(int_out_urb);
471 goto exit;
472 default:
473 /* what do we have here ? An unsupported Product-ID ? */
474 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n",
475 __func__, dev->product_id);
476 retval = -EFAULT;
477 goto exit;
478 }
479 error:
480 kfree(buf);
481 error_no_buffer:
482 usb_free_urb(int_out_urb);
483 error_no_urb:
484 atomic_dec(&dev->write_busy);
485 wake_up_interruptible(&dev->write_wait);
486 exit:
487 mutex_unlock(&dev->mutex);
488 return retval;
489 }
490
491 /*
492 * iowarrior_ioctl
493 */
iowarrior_ioctl(struct file * file,unsigned int cmd,unsigned long arg)494 static long iowarrior_ioctl(struct file *file, unsigned int cmd,
495 unsigned long arg)
496 {
497 struct iowarrior *dev = NULL;
498 __u8 *buffer;
499 __u8 __user *user_buffer;
500 int retval;
501 int io_res; /* checks for bytes read/written and copy_to/from_user results */
502
503 dev = file->private_data;
504 if (!dev)
505 return -ENODEV;
506
507 buffer = kzalloc(dev->report_size, GFP_KERNEL);
508 if (!buffer)
509 return -ENOMEM;
510
511 mutex_lock(&dev->mutex);
512
513 /* verify that the device wasn't unplugged */
514 if (!dev->present) {
515 retval = -ENODEV;
516 goto error_out;
517 }
518
519 retval = 0;
520 switch (cmd) {
521 case IOW_WRITE:
522 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
523 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG ||
524 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
525 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
526 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
527 user_buffer = (__u8 __user *)arg;
528 io_res = copy_from_user(buffer, user_buffer,
529 dev->report_size);
530 if (io_res) {
531 retval = -EFAULT;
532 } else {
533 io_res = usb_set_report(dev->interface, 2, 0,
534 buffer,
535 dev->report_size);
536 if (io_res < 0)
537 retval = io_res;
538 }
539 } else {
540 retval = -EINVAL;
541 dev_err(&dev->interface->dev,
542 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
543 dev->product_id);
544 }
545 break;
546 case IOW_READ:
547 user_buffer = (__u8 __user *)arg;
548 io_res = usb_get_report(dev->udev,
549 dev->interface->cur_altsetting, 1, 0,
550 buffer, dev->report_size);
551 if (io_res < 0)
552 retval = io_res;
553 else {
554 io_res = copy_to_user(user_buffer, buffer, dev->report_size);
555 if (io_res)
556 retval = -EFAULT;
557 }
558 break;
559 case IOW_GETINFO:
560 {
561 /* Report available information for the device */
562 struct iowarrior_info info;
563 /* needed for power consumption */
564 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
565
566 memset(&info, 0, sizeof(info));
567 /* directly from the descriptor */
568 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
569 info.product = dev->product_id;
570 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
571
572 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
573 info.speed = dev->udev->speed;
574 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
575 info.report_size = dev->report_size;
576
577 /* serial number string has been read earlier 8 chars or empty string */
578 memcpy(info.serial, dev->chip_serial,
579 sizeof(dev->chip_serial));
580 if (cfg_descriptor == NULL) {
581 info.power = -1; /* no information available */
582 } else {
583 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
584 info.power = cfg_descriptor->bMaxPower * 2;
585 }
586 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
587 sizeof(struct iowarrior_info));
588 if (io_res)
589 retval = -EFAULT;
590 break;
591 }
592 default:
593 /* return that we did not understand this ioctl call */
594 retval = -ENOTTY;
595 break;
596 }
597 error_out:
598 /* unlock the device */
599 mutex_unlock(&dev->mutex);
600 kfree(buffer);
601 return retval;
602 }
603
604 /*
605 * iowarrior_open
606 */
iowarrior_open(struct inode * inode,struct file * file)607 static int iowarrior_open(struct inode *inode, struct file *file)
608 {
609 struct iowarrior *dev = NULL;
610 struct usb_interface *interface;
611 int subminor;
612 int retval = 0;
613
614 subminor = iminor(inode);
615
616 interface = usb_find_interface(&iowarrior_driver, subminor);
617 if (!interface) {
618 pr_err("%s - error, can't find device for minor %d\n",
619 __func__, subminor);
620 return -ENODEV;
621 }
622
623 dev = usb_get_intfdata(interface);
624 if (!dev)
625 return -ENODEV;
626
627 mutex_lock(&dev->mutex);
628
629 /* Only one process can open each device, no sharing. */
630 if (dev->opened) {
631 retval = -EBUSY;
632 goto out;
633 }
634
635 /* setup interrupt handler for receiving values */
636 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
637 dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
638 retval = -EFAULT;
639 goto out;
640 }
641 /* increment our usage count for the driver */
642 ++dev->opened;
643
644 kref_get(&dev->kref);
645
646 /* save our object in the file's private structure */
647 file->private_data = dev;
648 retval = 0;
649
650 out:
651 mutex_unlock(&dev->mutex);
652 return retval;
653 }
654
655 /*
656 * iowarrior_release
657 */
iowarrior_release(struct inode * inode,struct file * file)658 static int iowarrior_release(struct inode *inode, struct file *file)
659 {
660 struct iowarrior *dev;
661
662 dev = file->private_data;
663 if (!dev)
664 return -ENODEV;
665
666 /* lock our device */
667 mutex_lock(&dev->mutex);
668 dev->opened = 0; /* we're closing now */
669
670 if (dev->present) {
671 usb_kill_urb(dev->int_in_urb);
672 wake_up_interruptible(&dev->read_wait);
673 wake_up_interruptible(&dev->write_wait);
674 }
675 mutex_unlock(&dev->mutex);
676
677 kref_put(&dev->kref, iowarrior_delete);
678
679 return 0;
680 }
681
iowarrior_poll(struct file * file,poll_table * wait)682 static __poll_t iowarrior_poll(struct file *file, poll_table * wait)
683 {
684 struct iowarrior *dev = file->private_data;
685 __poll_t mask = 0;
686
687 if (!dev->present)
688 return EPOLLERR | EPOLLHUP;
689
690 poll_wait(file, &dev->read_wait, wait);
691 poll_wait(file, &dev->write_wait, wait);
692
693 if (!dev->present)
694 return EPOLLERR | EPOLLHUP;
695
696 if (read_index(dev) != -1)
697 mask |= EPOLLIN | EPOLLRDNORM;
698
699 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
700 mask |= EPOLLOUT | EPOLLWRNORM;
701 return mask;
702 }
703
704 /*
705 * File operations needed when we register this driver.
706 * This assumes that this driver NEEDS file operations,
707 * of course, which means that the driver is expected
708 * to have a node in the /dev directory. If the USB
709 * device were for a network interface then the driver
710 * would use "struct net_driver" instead, and a serial
711 * device would use "struct tty_driver".
712 */
713 static const struct file_operations iowarrior_fops = {
714 .owner = THIS_MODULE,
715 .write = iowarrior_write,
716 .read = iowarrior_read,
717 .unlocked_ioctl = iowarrior_ioctl,
718 .open = iowarrior_open,
719 .release = iowarrior_release,
720 .poll = iowarrior_poll,
721 .llseek = noop_llseek,
722 };
723
iowarrior_devnode(const struct device * dev,umode_t * mode)724 static char *iowarrior_devnode(const struct device *dev, umode_t *mode)
725 {
726 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
727 }
728
729 /*
730 * usb class driver info in order to get a minor number from the usb core,
731 * and to have the device registered with devfs and the driver core
732 */
733 static struct usb_class_driver iowarrior_class = {
734 .name = "iowarrior%d",
735 .devnode = iowarrior_devnode,
736 .fops = &iowarrior_fops,
737 .minor_base = IOWARRIOR_MINOR_BASE,
738 };
739
740 /*---------------------------------*/
741 /* probe and disconnect functions */
742 /*---------------------------------*/
743 /*
744 * iowarrior_probe
745 *
746 * Called by the usb core when a new device is connected that it thinks
747 * this driver might be interested in.
748 */
iowarrior_probe(struct usb_interface * interface,const struct usb_device_id * id)749 static int iowarrior_probe(struct usb_interface *interface,
750 const struct usb_device_id *id)
751 {
752 struct usb_device *udev = interface_to_usbdev(interface);
753 struct iowarrior *dev = NULL;
754 struct usb_host_interface *iface_desc;
755 int retval = -ENOMEM;
756 int res;
757 int minor;
758
759 /* allocate memory for our device state and initialize it */
760 dev = kzalloc_obj(struct iowarrior);
761 if (!dev)
762 return retval;
763
764 kref_init(&dev->kref);
765 mutex_init(&dev->mutex);
766
767 atomic_set(&dev->intr_idx, 0);
768 atomic_set(&dev->read_idx, 0);
769 atomic_set(&dev->overflow_flag, 0);
770 init_waitqueue_head(&dev->read_wait);
771 atomic_set(&dev->write_busy, 0);
772 init_waitqueue_head(&dev->write_wait);
773
774 dev->udev = udev;
775 dev->interface = usb_get_intf(interface);
776
777 iface_desc = interface->cur_altsetting;
778 dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
779
780 init_usb_anchor(&dev->submitted);
781
782 res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
783 if (res) {
784 dev_err(&interface->dev, "no interrupt-in endpoint found\n");
785 retval = res;
786 goto error;
787 }
788
789 if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) ||
790 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) ||
791 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) ||
792 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) ||
793 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) {
794 res = usb_find_last_int_out_endpoint(iface_desc,
795 &dev->int_out_endpoint);
796 if (res) {
797 dev_err(&interface->dev, "no interrupt-out endpoint found\n");
798 retval = res;
799 goto error;
800 }
801 }
802
803 /* we have to check the report_size often, so remember it in the endianness suitable for our machine */
804 dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
805
806 /*
807 * Some devices need the report size to be different than the
808 * endpoint size.
809 */
810 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
811 switch (dev->product_id) {
812 case USB_DEVICE_ID_CODEMERCS_IOW56:
813 case USB_DEVICE_ID_CODEMERCS_IOW56AM:
814 dev->report_size = 7;
815 break;
816
817 case USB_DEVICE_ID_CODEMERCS_IOW28:
818 case USB_DEVICE_ID_CODEMERCS_IOW28L:
819 dev->report_size = 4;
820 break;
821
822 case USB_DEVICE_ID_CODEMERCS_IOW100:
823 dev->report_size = 12;
824 break;
825 }
826 }
827
828 /* create the urb and buffer for reading */
829 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
830 if (!dev->int_in_urb)
831 goto error;
832 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
833 if (!dev->int_in_buffer)
834 goto error;
835 usb_fill_int_urb(dev->int_in_urb, dev->udev,
836 usb_rcvintpipe(dev->udev,
837 dev->int_in_endpoint->bEndpointAddress),
838 dev->int_in_buffer, dev->report_size,
839 iowarrior_callback, dev,
840 dev->int_in_endpoint->bInterval);
841 /* create an internal buffer for interrupt data from the device */
842 dev->read_queue =
843 kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER,
844 GFP_KERNEL);
845 if (!dev->read_queue)
846 goto error;
847 /* Get the serial-number of the chip */
848 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
849 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
850 sizeof(dev->chip_serial));
851 if (strlen(dev->chip_serial) != 8)
852 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
853
854 /* Set the idle timeout to 0, if this is interface 0 */
855 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
856 usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
857 0x0A,
858 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
859 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
860 }
861 /* allow device read and ioctl */
862 dev->present = 1;
863
864 /* we can register the device now, as it is ready */
865 usb_set_intfdata(interface, dev);
866
867 retval = usb_register_dev(interface, &iowarrior_class);
868 if (retval) {
869 /* something prevented us from registering this driver */
870 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
871 goto error;
872 }
873
874 minor = interface->minor;
875
876 /* let the user know what node this device is now attached to */
877 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
878 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
879 iface_desc->desc.bInterfaceNumber, minor - IOWARRIOR_MINOR_BASE);
880 return retval;
881
882 error:
883 kref_put(&dev->kref, iowarrior_delete);
884
885 return retval;
886 }
887
888 /*
889 * iowarrior_disconnect
890 *
891 * Called by the usb core when the device is removed from the system.
892 */
iowarrior_disconnect(struct usb_interface * interface)893 static void iowarrior_disconnect(struct usb_interface *interface)
894 {
895 struct iowarrior *dev = usb_get_intfdata(interface);
896
897 usb_deregister_dev(interface, &iowarrior_class);
898
899 mutex_lock(&dev->mutex);
900
901 /* prevent device read, write and ioctl */
902 dev->present = 0;
903
904 /* write urbs are not stopped on close() so kill unconditionally */
905 usb_kill_anchored_urbs(&dev->submitted);
906
907 if (dev->opened) {
908 usb_kill_urb(dev->int_in_urb);
909 wake_up_interruptible(&dev->read_wait);
910 wake_up_interruptible(&dev->write_wait);
911 }
912
913 mutex_unlock(&dev->mutex);
914
915 kref_put(&dev->kref, iowarrior_delete);
916 }
917
918 /* usb specific object needed to register this driver with the usb subsystem */
919 static struct usb_driver iowarrior_driver = {
920 .name = "iowarrior",
921 .probe = iowarrior_probe,
922 .disconnect = iowarrior_disconnect,
923 .id_table = iowarrior_ids,
924 };
925
926 module_usb_driver(iowarrior_driver);
927