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USB: misc: ftdi-elan: clean up urb->status usage
[linux-2.6-block.git] / drivers / usb / misc / iowarrior.c
CommitLineData
946b960d
GKH		 1/*
2 * Native support for the I/O-Warrior USB devices
3 *
4 * Copyright (c) 2003-2005 Code Mercenaries GmbH
5 * written by Christian Lucht <lucht@codemercs.com>
6 *
7 * based on
8
9 * usb-skeleton.c by Greg Kroah-Hartman <greg@kroah.com>
10 * brlvger.c by Stephane Dalton <sdalton@videotron.ca>
11 * and St�hane Doyon <s.doyon@videotron.ca>
12 *
13 * Released under the GPLv2.
14 */
15
16#include <linux/module.h>
17#include <linux/usb.h>
18#include <linux/init.h>
19#include <linux/slab.h>
20#include <linux/sched.h>
21#include <linux/poll.h>
22#include <linux/version.h>
23#include <linux/usb/iowarrior.h>
24
25/* Version Information */
26#define DRIVER_VERSION "v0.4.0"
27#define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
28#define DRIVER_DESC "USB IO-Warrior driver (Linux 2.6.x)"
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
39/* Get a minor range for your devices from the usb maintainer */
40#ifdef CONFIG_USB_DYNAMIC_MINORS
41#define IOWARRIOR_MINOR_BASE 0
42#else
43#define IOWARRIOR_MINOR_BASE 208 // SKELETON_MINOR_BASE 192 + 16, not offical yet
44#endif
45
46/* interrupt input queue size */
47#define MAX_INTERRUPT_BUFFER 16
48/*
49 maximum number of urbs that are submitted for writes at the same time,
50 this applies to the IOWarrior56 only!
51 IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
52*/
53#define MAX_WRITES_IN_FLIGHT 4
54
55/* Use our own dbg macro */
56#undef dbg
57#define dbg( format, arg... ) do { if( debug ) printk( KERN_DEBUG __FILE__ ": " format "\n" , ## arg ); } while ( 0 )
58
59MODULE_AUTHOR(DRIVER_AUTHOR);
60MODULE_DESCRIPTION(DRIVER_DESC);
61MODULE_LICENSE("GPL");
62
63/* Module parameters */
64static int debug = 0;
65module_param(debug, bool, 0644);
66MODULE_PARM_DESC(debug, "debug=1 enables debugging messages");
67
68static struct usb_driver iowarrior_driver;
69
70/*--------------*/
71/* data */
72/*--------------*/
73
74/* Structure to hold all of our device specific stuff */
75struct iowarrior {
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 unsigned char minor; /* the starting minor number for this device */
80 struct usb_endpoint_descriptor *int_out_endpoint; /* endpoint for reading (needed for IOW56 only) */
81 struct usb_endpoint_descriptor *int_in_endpoint; /* endpoint for reading */
82 struct urb *int_in_urb; /* the urb for reading data */
83 unsigned char *int_in_buffer; /* buffer for data to be read */
84 unsigned char serial_number; /* to detect lost packages */
85 unsigned char *read_queue; /* size is MAX_INTERRUPT_BUFFER * packet size */
86 wait_queue_head_t read_wait;
87 wait_queue_head_t write_wait; /* wait-queue for writing to the device */
88 atomic_t write_busy; /* number of write-urbs submitted */
89 atomic_t read_idx;
90 atomic_t intr_idx;
91 spinlock_t intr_idx_lock; /* protects intr_idx */
92 atomic_t overflow_flag; /* signals an index 'rollover' */
93 int present; /* this is 1 as long as the device is connected */
94 int opened; /* this is 1 if the device is currently open */
95 char chip_serial[9]; /* the serial number string of the chip connected */
96 int report_size; /* number of bytes in a report */
97 u16 product_id;
98};
99
100/*--------------*/
101/* globals */
102/*--------------*/
946b960d
GKH		 103
104/*
105 * USB spec identifies 5 second timeouts.
106 */
107#define GET_TIMEOUT 5
108#define USB_REQ_GET_REPORT 0x01
109//#if 0
110static int usb_get_report(struct usb_device *dev,
111 struct usb_host_interface *inter, unsigned char type,
112 unsigned char id, void *buf, int size)
113{
114 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
115 USB_REQ_GET_REPORT,
116 USB_DIR_IN | USB_TYPE_CLASS |
117 USB_RECIP_INTERFACE, (type << 8) + id,
118 inter->desc.bInterfaceNumber, buf, size,
147c5a17 119 GET_TIMEOUT*HZ);
946b960d
GKH		 120}
121//#endif
122
123#define USB_REQ_SET_REPORT 0x09
124
125static int usb_set_report(struct usb_interface *intf, unsigned char type,
126 unsigned char id, void *buf, int size)
127{
128 return usb_control_msg(interface_to_usbdev(intf),
129 usb_sndctrlpipe(interface_to_usbdev(intf), 0),
130 USB_REQ_SET_REPORT,
131 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
132 (type << 8) + id,
133 intf->cur_altsetting->desc.bInterfaceNumber, buf,
147c5a17 134 size, HZ);
946b960d
GKH		 135}
136
137/*---------------------*/
138/* driver registration */
139/*---------------------*/
140/* table of devices that work with this driver */
141static struct usb_device_id iowarrior_ids[] = {
142 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
143 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
144 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
145 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
146 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
147 {} /* Terminating entry */
148};
149MODULE_DEVICE_TABLE(usb, iowarrior_ids);
150
151/*
152 * USB callback handler for reading data
153 */
154static void iowarrior_callback(struct urb *urb)
155{
156 struct iowarrior *dev = (struct iowarrior *)urb->context;
157 int intr_idx;
158 int read_idx;
159 int aux_idx;
160 int offset;
161 int status;
162
163 switch (urb->status) {
164 case 0:
165 /* success */
166 break;
167 case -ECONNRESET:
168 case -ENOENT:
169 case -ESHUTDOWN:
170 return;
171 default:
172 goto exit;
173 }
174
175 spin_lock(&dev->intr_idx_lock);
176 intr_idx = atomic_read(&dev->intr_idx);
177 /* aux_idx become previous intr_idx */
178 aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
179 read_idx = atomic_read(&dev->read_idx);
180
181 /* queue is not empty and it's interface 0 */
182 if ((intr_idx != read_idx)
183 && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
184 /* + 1 for serial number */
185 offset = aux_idx * (dev->report_size + 1);
186 if (!memcmp
187 (dev->read_queue + offset, urb->transfer_buffer,
188 dev->report_size)) {
189 /* equal values on interface 0 will be ignored */
190 spin_unlock(&dev->intr_idx_lock);
191 goto exit;
192 }
193 }
194
195 /* aux_idx become next intr_idx */
196 aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
197 if (read_idx == aux_idx) {
198 /* queue full, dropping oldest input */
199 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
200 atomic_set(&dev->read_idx, read_idx);
201 atomic_set(&dev->overflow_flag, 1);
202 }
203
204 /* +1 for serial number */
205 offset = intr_idx * (dev->report_size + 1);
206 memcpy(dev->read_queue + offset, urb->transfer_buffer,
207 dev->report_size);
208 *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
209
210 atomic_set(&dev->intr_idx, aux_idx);
211 spin_unlock(&dev->intr_idx_lock);
212 /* tell the blocking read about the new data */
213 wake_up_interruptible(&dev->read_wait);
214
215exit:
216 status = usb_submit_urb(urb, GFP_ATOMIC);
217 if (status)
218 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d",
219 __FUNCTION__, status);
220
221}
222
223/*
224 * USB Callback handler for write-ops
225 */
226static void iowarrior_write_callback(struct urb *urb)
227{
228 struct iowarrior *dev;
229 dev = (struct iowarrior *)urb->context;
230 /* sync/async unlink faults aren't errors */
231 if (urb->status &&
232 !(urb->status == -ENOENT ||
233 urb->status == -ECONNRESET || urb->status == -ESHUTDOWN)) {
234 dbg("%s - nonzero write bulk status received: %d",
235 __func__, urb->status);
236 }
237 /* free up our allocated buffer */
238 usb_buffer_free(urb->dev, urb->transfer_buffer_length,
239 urb->transfer_buffer, urb->transfer_dma);
240 /* tell a waiting writer the interrupt-out-pipe is available again */
241 atomic_dec(&dev->write_busy);
242 wake_up_interruptible(&dev->write_wait);
243}
244
245/**
246 * iowarrior_delete
247 */
248static inline void iowarrior_delete(struct iowarrior *dev)
249{
250 dbg("%s - minor %d", __func__, dev->minor);
251 kfree(dev->int_in_buffer);
252 usb_free_urb(dev->int_in_urb);
253 kfree(dev->read_queue);
254 kfree(dev);
255}
256
257/*---------------------*/
258/* fops implementation */
259/*---------------------*/
260
261static int read_index(struct iowarrior *dev)
262{
263 int intr_idx, read_idx;
264
265 read_idx = atomic_read(&dev->read_idx);
266 intr_idx = atomic_read(&dev->intr_idx);
267
268 return (read_idx == intr_idx ? -1 : read_idx);
269}
270
271/**
272 * iowarrior_read
273 */
274static ssize_t iowarrior_read(struct file *file, char __user *buffer,
275 size_t count, loff_t *ppos)
276{
277 struct iowarrior *dev;
278 int read_idx;
279 int offset;
280
281 dev = (struct iowarrior *)file->private_data;
282
283 /* verify that the device wasn't unplugged */
284 if (dev == NULL || !dev->present)
285 return -ENODEV;
286
287 dbg("%s - minor %d, count = %zd", __func__, dev->minor, count);
288
289 /* read count must be packet size (+ time stamp) */
290 if ((count != dev->report_size)
291 && (count != (dev->report_size + 1)))
292 return -EINVAL;
293
294 /* repeat until no buffer overrun in callback handler occur */
295 do {
296 atomic_set(&dev->overflow_flag, 0);
297 if ((read_idx = read_index(dev)) == -1) {
298 /* queue emty */
299 if (file->f_flags & O_NONBLOCK)
300 return -EAGAIN;
301 else {
302 //next line will return when there is either new data, or the device is unplugged
303 int r = wait_event_interruptible(dev->read_wait,
304 (!dev->present
305 || (read_idx =
306 read_index
307 (dev)) !=
308 -1));
309 if (r) {
310 //we were interrupted by a signal
311 return -ERESTART;
312 }
313 if (!dev->present) {
314 //The device was unplugged
315 return -ENODEV;
316 }
317 if (read_idx == -1) {
318 // Can this happen ???
319 return 0;
320 }
321 }
322 }
323
324 offset = read_idx * (dev->report_size + 1);
325 if (copy_to_user(buffer, dev->read_queue + offset, count)) {
326 return -EFAULT;
327 }
328 } while (atomic_read(&dev->overflow_flag));
329
330 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
331 atomic_set(&dev->read_idx, read_idx);
332 return count;
333}
334
335/*
336 * iowarrior_write
337 */
338static ssize_t iowarrior_write(struct file *file,
339 const char __user *user_buffer,
340 size_t count, loff_t *ppos)
341{
342 struct iowarrior *dev;
343 int retval = 0;
344 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */
345 struct urb *int_out_urb = NULL;
346
347 dev = (struct iowarrior *)file->private_data;
348
349 mutex_lock(&dev->mutex);
350 /* verify that the device wasn't unplugged */
351 if (dev == NULL || !dev->present) {
352 retval = -ENODEV;
353 goto exit;
354 }
355 dbg("%s - minor %d, count = %zd", __func__, dev->minor, count);
356 /* if count is 0 we're already done */
357 if (count == 0) {
358 retval = 0;
359 goto exit;
360 }
361 /* We only accept full reports */
362 if (count != dev->report_size) {
363 retval = -EINVAL;
364 goto exit;
365 }
366 switch (dev->product_id) {
367 case USB_DEVICE_ID_CODEMERCS_IOW24:
368 case USB_DEVICE_ID_CODEMERCS_IOWPV1:
369 case USB_DEVICE_ID_CODEMERCS_IOWPV2:
370 case USB_DEVICE_ID_CODEMERCS_IOW40:
371 /* IOW24 and IOW40 use a synchronous call */
372 buf = kmalloc(8, GFP_KERNEL); /* 8 bytes are enough for both products */
373 if (!buf) {
374 retval = -ENOMEM;
375 goto exit;
376 }
377 if (copy_from_user(buf, user_buffer, count)) {
378 retval = -EFAULT;
379 kfree(buf);
380 goto exit;
381 }
382 retval = usb_set_report(dev->interface, 2, 0, buf, count);
383 kfree(buf);
384 goto exit;
385 break;
386 case USB_DEVICE_ID_CODEMERCS_IOW56:
387 /* The IOW56 uses asynchronous IO and more urbs */
388 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
389 /* Wait until we are below the limit for submitted urbs */
390 if (file->f_flags & O_NONBLOCK) {
391 retval = -EAGAIN;
392 goto exit;
393 } else {
394 retval = wait_event_interruptible(dev->write_wait,
395 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
396 if (retval) {
397 /* we were interrupted by a signal */
398 retval = -ERESTART;
399 goto exit;
400 }
401 if (!dev->present) {
402 /* The device was unplugged */
403 retval = -ENODEV;
404 goto exit;
405 }
406 if (!dev->opened) {
407 /* We were closed while waiting for an URB */
408 retval = -ENODEV;
409 goto exit;
410 }
411 }
412 }
413 atomic_inc(&dev->write_busy);
414 int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
415 if (!int_out_urb) {
416 retval = -ENOMEM;
417 dbg("%s Unable to allocate urb ", __func__);
f81ee4d5 418 goto error_no_urb;
946b960d
GKH		 419 }
420 buf = usb_buffer_alloc(dev->udev, dev->report_size,
421 GFP_KERNEL, &int_out_urb->transfer_dma);
422 if (!buf) {
423 retval = -ENOMEM;
424 dbg("%s Unable to allocate buffer ", __func__);
f81ee4d5 425 goto error_no_buffer;
946b960d
GKH		 426 }
427 usb_fill_int_urb(int_out_urb, dev->udev,
428 usb_sndintpipe(dev->udev,
429 dev->int_out_endpoint->bEndpointAddress),
430 buf, dev->report_size,
431 iowarrior_write_callback, dev,
432 dev->int_out_endpoint->bInterval);
433 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
434 if (copy_from_user(buf, user_buffer, count)) {
435 retval = -EFAULT;
436 goto error;
437 }
438 retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
439 if (retval) {
440 dbg("%s submit error %d for urb nr.%d", __func__,
441 retval, atomic_read(&dev->write_busy));
442 goto error;
443 }
444 /* submit was ok */
445 retval = count;
446 usb_free_urb(int_out_urb);
447 goto exit;
448 break;
449 default:
450 /* what do we have here ? An unsupported Product-ID ? */
451 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x",
452 __FUNCTION__, dev->product_id);
453 retval = -EFAULT;
454 goto exit;
455 break;
456 }
457error:
458 usb_buffer_free(dev->udev, dev->report_size, buf,
459 int_out_urb->transfer_dma);
f81ee4d5 460error_no_buffer:
946b960d 461 usb_free_urb(int_out_urb);
f81ee4d5 462error_no_urb:
946b960d
GKH		 463 atomic_dec(&dev->write_busy);
464 wake_up_interruptible(&dev->write_wait);
465exit:
466 mutex_unlock(&dev->mutex);
467 return retval;
468}
469
470/**
471 * iowarrior_ioctl
472 */
473static int iowarrior_ioctl(struct inode *inode, struct file *file,
474 unsigned int cmd, unsigned long arg)
475{
476 struct iowarrior *dev = NULL;
477 __u8 *buffer;
478 __u8 __user *user_buffer;
479 int retval;
480 int io_res; /* checks for bytes read/written and copy_to/from_user results */
481
482 dev = (struct iowarrior *)file->private_data;
483 if (dev == NULL) {
484 return -ENODEV;
485 }
486
487 buffer = kzalloc(dev->report_size, GFP_KERNEL);
488 if (!buffer)
489 return -ENOMEM;
490
491 /* lock this object */
492 mutex_lock(&dev->mutex);
493
494 /* verify that the device wasn't unplugged */
495 if (!dev->present) {
fc0f8fc9
ON		 496 retval = -ENODEV;
497 goto error_out;
946b960d
GKH		 498 }
499
500 dbg("%s - minor %d, cmd 0x%.4x, arg %ld", __func__, dev->minor, cmd,
501 arg);
502
503 retval = 0;
504 io_res = 0;
505 switch (cmd) {
506 case IOW_WRITE:
507 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
508 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
509 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
510 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
511 user_buffer = (__u8 __user *)arg;
512 io_res = copy_from_user(buffer, user_buffer,
513 dev->report_size);
514 if (io_res) {
515 retval = -EFAULT;
516 } else {
517 io_res = usb_set_report(dev->interface, 2, 0,
518 buffer,
519 dev->report_size);
520 if (io_res < 0)
521 retval = io_res;
522 }
523 } else {
524 retval = -EINVAL;
525 dev_err(&dev->interface->dev,
526 "ioctl 'IOW_WRITE' is not supported for product=0x%x.",
527 dev->product_id);
528 }
529 break;
530 case IOW_READ:
531 user_buffer = (__u8 __user *)arg;
532 io_res = usb_get_report(dev->udev,
533 dev->interface->cur_altsetting, 1, 0,
534 buffer, dev->report_size);
535 if (io_res < 0)
536 retval = io_res;
537 else {
538 io_res = copy_to_user(user_buffer, buffer, dev->report_size);
539 if (io_res < 0)
540 retval = -EFAULT;
541 }
542 break;
543 case IOW_GETINFO:
544 {
545 /* Report available information for the device */
546 struct iowarrior_info info;
547 /* needed for power consumption */
548 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
549
550 /* directly from the descriptor */
551 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
552 info.product = dev->product_id;
553 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
554
555 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
556 info.speed = le16_to_cpu(dev->udev->speed);
557 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
558 info.report_size = dev->report_size;
559
560 /* serial number string has been read earlier 8 chars or empty string */
561 memcpy(info.serial, dev->chip_serial,
562 sizeof(dev->chip_serial));
563 if (cfg_descriptor == NULL) {
564 info.power = -1; /* no information available */
565 } else {
566 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
567 info.power = cfg_descriptor->bMaxPower * 2;
568 }
569 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
570 sizeof(struct iowarrior_info));
571 if (io_res < 0)
572 retval = -EFAULT;
573 break;
574 }
575 default:
576 /* return that we did not understand this ioctl call */
577 retval = -ENOTTY;
578 break;
579 }
fc0f8fc9 580error_out:
946b960d
GKH		 581 /* unlock the device */
582 mutex_unlock(&dev->mutex);
fc0f8fc9 583 kfree(buffer);
946b960d
GKH		 584 return retval;
585}
586
587/**
588 * iowarrior_open
589 */
590static int iowarrior_open(struct inode *inode, struct file *file)
591{
592 struct iowarrior *dev = NULL;
593 struct usb_interface *interface;
594 int subminor;
595 int retval = 0;
596
597 dbg("%s", __func__);
598
599 subminor = iminor(inode);
600
946b960d
GKH		 601 interface = usb_find_interface(&iowarrior_driver, subminor);
602 if (!interface) {
603 err("%s - error, can't find device for minor %d", __FUNCTION__,
604 subminor);
d4ead16f 605 return -ENODEV;
946b960d
GKH		 606 }
607
608 dev = usb_get_intfdata(interface);
d4ead16f
AS		 609 if (!dev)
610 return -ENODEV;
611
612 mutex_lock(&dev->mutex);
946b960d
GKH		 613
614 /* Only one process can open each device, no sharing. */
615 if (dev->opened) {
616 retval = -EBUSY;
617 goto out;
618 }
619
620 /* setup interrupt handler for receiving values */
621 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
622 dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
623 retval = -EFAULT;
624 goto out;
625 }
626 /* increment our usage count for the driver */
627 ++dev->opened;
628 /* save our object in the file's private structure */
629 file->private_data = dev;
630 retval = 0;
631
632out:
d4ead16f 633 mutex_unlock(&dev->mutex);
946b960d
GKH		 634 return retval;
635}
636
637/**
638 * iowarrior_release
639 */
640static int iowarrior_release(struct inode *inode, struct file *file)
641{
642 struct iowarrior *dev;
643 int retval = 0;
644
645 dev = (struct iowarrior *)file->private_data;
646 if (dev == NULL) {
647 return -ENODEV;
648 }
649
650 dbg("%s - minor %d", __func__, dev->minor);
651
652 /* lock our device */
653 mutex_lock(&dev->mutex);
654
655 if (dev->opened <= 0) {
656 retval = -ENODEV; /* close called more than once */
657 mutex_unlock(&dev->mutex);
658 } else {
659 dev->opened = 0; /* we're closeing now */
660 retval = 0;
661 if (dev->present) {
662 /*
663 The device is still connected so we only shutdown
664 pending read-/write-ops.
665 */
666 usb_kill_urb(dev->int_in_urb);
667 wake_up_interruptible(&dev->read_wait);
668 wake_up_interruptible(&dev->write_wait);
669 mutex_unlock(&dev->mutex);
670 } else {
671 /* The device was unplugged, cleanup resources */
672 mutex_unlock(&dev->mutex);
673 iowarrior_delete(dev);
674 }
675 }
676 return retval;
677}
678
679static unsigned iowarrior_poll(struct file *file, poll_table * wait)
680{
681 struct iowarrior *dev = file->private_data;
682 unsigned int mask = 0;
683
684 if (!dev->present)
685 return POLLERR | POLLHUP;
686
687 poll_wait(file, &dev->read_wait, wait);
688 poll_wait(file, &dev->write_wait, wait);
689
690 if (!dev->present)
691 return POLLERR | POLLHUP;
692
693 if (read_index(dev) != -1)
694 mask |= POLLIN | POLLRDNORM;
695
696 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
697 mask |= POLLOUT | POLLWRNORM;
698 return mask;
699}
700
701/*
702 * File operations needed when we register this driver.
703 * This assumes that this driver NEEDS file operations,
704 * of course, which means that the driver is expected
705 * to have a node in the /dev directory. If the USB
706 * device were for a network interface then the driver
707 * would use "struct net_driver" instead, and a serial
708 * device would use "struct tty_driver".
709 */
710static struct file_operations iowarrior_fops = {
711 .owner = THIS_MODULE,
712 .write = iowarrior_write,
713 .read = iowarrior_read,
714 .ioctl = iowarrior_ioctl,
715 .open = iowarrior_open,
716 .release = iowarrior_release,
717 .poll = iowarrior_poll,
718};
719
720/*
721 * usb class driver info in order to get a minor number from the usb core,
722 * and to have the device registered with devfs and the driver core
723 */
724static struct usb_class_driver iowarrior_class = {
725 .name = "iowarrior%d",
726 .fops = &iowarrior_fops,
727 .minor_base = IOWARRIOR_MINOR_BASE,
728};
729
730/*---------------------------------*/
731/* probe and disconnect functions */
732/*---------------------------------*/
733/**
734 * iowarrior_probe
735 *
736 * Called by the usb core when a new device is connected that it thinks
737 * this driver might be interested in.
738 */
739static int iowarrior_probe(struct usb_interface *interface,
740 const struct usb_device_id *id)
741{
742 struct usb_device *udev = interface_to_usbdev(interface);
743 struct iowarrior *dev = NULL;
744 struct usb_host_interface *iface_desc;
745 struct usb_endpoint_descriptor *endpoint;
746 int i;
747 int retval = -ENOMEM;
946b960d
GKH		 748
749 /* allocate memory for our device state and intialize it */
750 dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
751 if (dev == NULL) {
752 dev_err(&interface->dev, "Out of memory");
753 return retval;
754 }
755
756 mutex_init(&dev->mutex);
757
758 atomic_set(&dev->intr_idx, 0);
759 atomic_set(&dev->read_idx, 0);
760 spin_lock_init(&dev->intr_idx_lock);
761 atomic_set(&dev->overflow_flag, 0);
762 init_waitqueue_head(&dev->read_wait);
763 atomic_set(&dev->write_busy, 0);
764 init_waitqueue_head(&dev->write_wait);
765
766 dev->udev = udev;
767 dev->interface = interface;
768
769 iface_desc = interface->cur_altsetting;
770 dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
771
772 /* set up the endpoint information */
773 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
774 endpoint = &iface_desc->endpoint[i].desc;
775
776 if (usb_endpoint_is_int_in(endpoint))
777 dev->int_in_endpoint = endpoint;
778 if (usb_endpoint_is_int_out(endpoint))
779 /* this one will match for the IOWarrior56 only */
780 dev->int_out_endpoint = endpoint;
781 }
782 /* we have to check the report_size often, so remember it in the endianess suitable for our machine */
783 dev->report_size = le16_to_cpu(dev->int_in_endpoint->wMaxPacketSize);
784 if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&
785 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56))
786 /* IOWarrior56 has wMaxPacketSize different from report size */
787 dev->report_size = 7;
788
789 /* create the urb and buffer for reading */
790 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
791 if (!dev->int_in_urb) {
792 dev_err(&interface->dev, "Couldn't allocate interrupt_in_urb\n");
793 goto error;
794 }
795 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
796 if (!dev->int_in_buffer) {
797 dev_err(&interface->dev, "Couldn't allocate int_in_buffer\n");
798 goto error;
799 }
800 usb_fill_int_urb(dev->int_in_urb, dev->udev,
801 usb_rcvintpipe(dev->udev,
802 dev->int_in_endpoint->bEndpointAddress),
803 dev->int_in_buffer, dev->report_size,
804 iowarrior_callback, dev,
805 dev->int_in_endpoint->bInterval);
806 /* create an internal buffer for interrupt data from the device */
807 dev->read_queue =
808 kmalloc(((dev->report_size + 1) * MAX_INTERRUPT_BUFFER),
809 GFP_KERNEL);
810 if (!dev->read_queue) {
811 dev_err(&interface->dev, "Couldn't allocate read_queue\n");
812 goto error;
813 }
814 /* Get the serial-number of the chip */
815 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
816 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
817 sizeof(dev->chip_serial));
818 if (strlen(dev->chip_serial) != 8)
819 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
820
821 /* Set the idle timeout to 0, if this is interface 0 */
822 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
147c5a17
EF		 823 usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
824 0x0A,
825 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
826 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
946b960d
GKH		 827 }
828 /* allow device read and ioctl */
829 dev->present = 1;
830
831 /* we can register the device now, as it is ready */
832 usb_set_intfdata(interface, dev);
833
834 retval = usb_register_dev(interface, &iowarrior_class);
835 if (retval) {
836 /* something prevented us from registering this driver */
837 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
838 usb_set_intfdata(interface, NULL);
839 goto error;
840 }
841
842 dev->minor = interface->minor;
843
844 /* let the user know what node this device is now attached to */
845 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
846 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
847 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
848 return retval;
849
850error:
851 iowarrior_delete(dev);
852 return retval;
853}
854
855/**
856 * iowarrior_disconnect
857 *
858 * Called by the usb core when the device is removed from the system.
859 */
860static void iowarrior_disconnect(struct usb_interface *interface)
861{
862 struct iowarrior *dev;
863 int minor;
864
946b960d
GKH		 865 dev = usb_get_intfdata(interface);
866 usb_set_intfdata(interface, NULL);
867
946b960d
GKH		 868 minor = dev->minor;
869
870 /* give back our minor */
871 usb_deregister_dev(interface, &iowarrior_class);
872
d4ead16f
AS		 873 mutex_lock(&dev->mutex);
874
946b960d
GKH		 875 /* prevent device read, write and ioctl */
876 dev->present = 0;
877
878 mutex_unlock(&dev->mutex);
879
880 if (dev->opened) {
881 /* There is a process that holds a filedescriptor to the device ,
882 so we only shutdown read-/write-ops going on.
883 Deleting the device is postponed until close() was called.
884 */
885 usb_kill_urb(dev->int_in_urb);
886 wake_up_interruptible(&dev->read_wait);
887 wake_up_interruptible(&dev->write_wait);
888 } else {
889 /* no process is using the device, cleanup now */
890 iowarrior_delete(dev);
891 }
946b960d
GKH		 892
893 dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
894 minor - IOWARRIOR_MINOR_BASE);
895}
896
897/* usb specific object needed to register this driver with the usb subsystem */
898static struct usb_driver iowarrior_driver = {
899 .name = "iowarrior",
900 .probe = iowarrior_probe,
901 .disconnect = iowarrior_disconnect,
902 .id_table = iowarrior_ids,
903};
904
905static int __init iowarrior_init(void)
906{
907 return usb_register(&iowarrior_driver);
908}
909
910static void __exit iowarrior_exit(void)
911{
912 usb_deregister(&iowarrior_driver);
913}
914
915module_init(iowarrior_init);
916module_exit(iowarrior_exit);
Linux 6.x block layer and io_uring tree(s)