Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6] / drivers / usb / misc / iowarrior.c
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
59 MODULE_AUTHOR(DRIVER_AUTHOR);
60 MODULE_DESCRIPTION(DRIVER_DESC);
61 MODULE_LICENSE("GPL");
62
63 /* Module parameters */
64 static int debug = 0;
65 module_param(debug, bool, 0644);
66 MODULE_PARM_DESC(debug, "debug=1 enables debugging messages");
67
68 static struct usb_driver iowarrior_driver;
69
70 /*--------------*/
71 /*     data     */
72 /*--------------*/
73
74 /* Structure to hold all of our device specific stuff */
75 struct 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 /*--------------*/
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
110 static 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,
119                                GET_TIMEOUT*HZ);
120 }
121 //#endif
122
123 #define USB_REQ_SET_REPORT 0x09
124
125 static 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,
134                                size, HZ);
135 }
136
137 /*---------------------*/
138 /* driver registration */
139 /*---------------------*/
140 /* table of devices that work with this driver */
141 static 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 };
149 MODULE_DEVICE_TABLE(usb, iowarrior_ids);
150
151 /*
152  * USB callback handler for reading data
153  */
154 static 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 = urb->status;
162         int retval;
163
164         switch (status) {
165         case 0:
166                 /* success */
167                 break;
168         case -ECONNRESET:
169         case -ENOENT:
170         case -ESHUTDOWN:
171                 return;
172         default:
173                 goto exit;
174         }
175
176         spin_lock(&dev->intr_idx_lock);
177         intr_idx = atomic_read(&dev->intr_idx);
178         /* aux_idx become previous intr_idx */
179         aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
180         read_idx = atomic_read(&dev->read_idx);
181
182         /* queue is not empty and it's interface 0 */
183         if ((intr_idx != read_idx)
184             && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
185                 /* + 1 for serial number */
186                 offset = aux_idx * (dev->report_size + 1);
187                 if (!memcmp
188                     (dev->read_queue + offset, urb->transfer_buffer,
189                      dev->report_size)) {
190                         /* equal values on interface 0 will be ignored */
191                         spin_unlock(&dev->intr_idx_lock);
192                         goto exit;
193                 }
194         }
195
196         /* aux_idx become next intr_idx */
197         aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
198         if (read_idx == aux_idx) {
199                 /* queue full, dropping oldest input */
200                 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
201                 atomic_set(&dev->read_idx, read_idx);
202                 atomic_set(&dev->overflow_flag, 1);
203         }
204
205         /* +1 for serial number */
206         offset = intr_idx * (dev->report_size + 1);
207         memcpy(dev->read_queue + offset, urb->transfer_buffer,
208                dev->report_size);
209         *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
210
211         atomic_set(&dev->intr_idx, aux_idx);
212         spin_unlock(&dev->intr_idx_lock);
213         /* tell the blocking read about the new data */
214         wake_up_interruptible(&dev->read_wait);
215
216 exit:
217         retval = usb_submit_urb(urb, GFP_ATOMIC);
218         if (retval)
219                 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d",
220                         __FUNCTION__, retval);
221
222 }
223
224 /*
225  * USB Callback handler for write-ops
226  */
227 static void iowarrior_write_callback(struct urb *urb)
228 {
229         struct iowarrior *dev;
230         int status = urb->status;
231
232         dev = (struct iowarrior *)urb->context;
233         /* sync/async unlink faults aren't errors */
234         if (status &&
235             !(status == -ENOENT ||
236               status == -ECONNRESET || status == -ESHUTDOWN)) {
237                 dbg("%s - nonzero write bulk status received: %d",
238                     __func__, status);
239         }
240         /* free up our allocated buffer */
241         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
242                         urb->transfer_buffer, urb->transfer_dma);
243         /* tell a waiting writer the interrupt-out-pipe is available again */
244         atomic_dec(&dev->write_busy);
245         wake_up_interruptible(&dev->write_wait);
246 }
247
248 /**
249  *      iowarrior_delete
250  */
251 static inline void iowarrior_delete(struct iowarrior *dev)
252 {
253         dbg("%s - minor %d", __func__, dev->minor);
254         kfree(dev->int_in_buffer);
255         usb_free_urb(dev->int_in_urb);
256         kfree(dev->read_queue);
257         kfree(dev);
258 }
259
260 /*---------------------*/
261 /* fops implementation */
262 /*---------------------*/
263
264 static int read_index(struct iowarrior *dev)
265 {
266         int intr_idx, read_idx;
267
268         read_idx = atomic_read(&dev->read_idx);
269         intr_idx = atomic_read(&dev->intr_idx);
270
271         return (read_idx == intr_idx ? -1 : read_idx);
272 }
273
274 /**
275  *  iowarrior_read
276  */
277 static ssize_t iowarrior_read(struct file *file, char __user *buffer,
278                               size_t count, loff_t *ppos)
279 {
280         struct iowarrior *dev;
281         int read_idx;
282         int offset;
283
284         dev = (struct iowarrior *)file->private_data;
285
286         /* verify that the device wasn't unplugged */
287         if (dev == NULL || !dev->present)
288                 return -ENODEV;
289
290         dbg("%s - minor %d, count = %zd", __func__, dev->minor, count);
291
292         /* read count must be packet size (+ time stamp) */
293         if ((count != dev->report_size)
294             && (count != (dev->report_size + 1)))
295                 return -EINVAL;
296
297         /* repeat until no buffer overrun in callback handler occur */
298         do {
299                 atomic_set(&dev->overflow_flag, 0);
300                 if ((read_idx = read_index(dev)) == -1) {
301                         /* queue emty */
302                         if (file->f_flags & O_NONBLOCK)
303                                 return -EAGAIN;
304                         else {
305                                 //next line will return when there is either new data, or the device is unplugged
306                                 int r = wait_event_interruptible(dev->read_wait,
307                                                                  (!dev->present
308                                                                   || (read_idx =
309                                                                       read_index
310                                                                       (dev)) !=
311                                                                   -1));
312                                 if (r) {
313                                         //we were interrupted by a signal
314                                         return -ERESTART;
315                                 }
316                                 if (!dev->present) {
317                                         //The device was unplugged
318                                         return -ENODEV;
319                                 }
320                                 if (read_idx == -1) {
321                                         // Can this happen ???
322                                         return 0;
323                                 }
324                         }
325                 }
326
327                 offset = read_idx * (dev->report_size + 1);
328                 if (copy_to_user(buffer, dev->read_queue + offset, count)) {
329                         return -EFAULT;
330                 }
331         } while (atomic_read(&dev->overflow_flag));
332
333         read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
334         atomic_set(&dev->read_idx, read_idx);
335         return count;
336 }
337
338 /*
339  * iowarrior_write
340  */
341 static ssize_t iowarrior_write(struct file *file,
342                                const char __user *user_buffer,
343                                size_t count, loff_t *ppos)
344 {
345         struct iowarrior *dev;
346         int retval = 0;
347         char *buf = NULL;       /* for IOW24 and IOW56 we need a buffer */
348         struct urb *int_out_urb = NULL;
349
350         dev = (struct iowarrior *)file->private_data;
351
352         mutex_lock(&dev->mutex);
353         /* verify that the device wasn't unplugged */
354         if (dev == NULL || !dev->present) {
355                 retval = -ENODEV;
356                 goto exit;
357         }
358         dbg("%s - minor %d, count = %zd", __func__, dev->minor, count);
359         /* if count is 0 we're already done */
360         if (count == 0) {
361                 retval = 0;
362                 goto exit;
363         }
364         /* We only accept full reports */
365         if (count != dev->report_size) {
366                 retval = -EINVAL;
367                 goto exit;
368         }
369         switch (dev->product_id) {
370         case USB_DEVICE_ID_CODEMERCS_IOW24:
371         case USB_DEVICE_ID_CODEMERCS_IOWPV1:
372         case USB_DEVICE_ID_CODEMERCS_IOWPV2:
373         case USB_DEVICE_ID_CODEMERCS_IOW40:
374                 /* IOW24 and IOW40 use a synchronous call */
375                 buf = kmalloc(8, GFP_KERNEL);   /* 8 bytes are enough for both products */
376                 if (!buf) {
377                         retval = -ENOMEM;
378                         goto exit;
379                 }
380                 if (copy_from_user(buf, user_buffer, count)) {
381                         retval = -EFAULT;
382                         kfree(buf);
383                         goto exit;
384                 }
385                 retval = usb_set_report(dev->interface, 2, 0, buf, count);
386                 kfree(buf);
387                 goto exit;
388                 break;
389         case USB_DEVICE_ID_CODEMERCS_IOW56:
390                 /* The IOW56 uses asynchronous IO and more urbs */
391                 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
392                         /* Wait until we are below the limit for submitted urbs */
393                         if (file->f_flags & O_NONBLOCK) {
394                                 retval = -EAGAIN;
395                                 goto exit;
396                         } else {
397                                 retval = wait_event_interruptible(dev->write_wait,
398                                                                   (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
399                                 if (retval) {
400                                         /* we were interrupted by a signal */
401                                         retval = -ERESTART;
402                                         goto exit;
403                                 }
404                                 if (!dev->present) {
405                                         /* The device was unplugged */
406                                         retval = -ENODEV;
407                                         goto exit;
408                                 }
409                                 if (!dev->opened) {
410                                         /* We were closed while waiting for an URB */
411                                         retval = -ENODEV;
412                                         goto exit;
413                                 }
414                         }
415                 }
416                 atomic_inc(&dev->write_busy);
417                 int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
418                 if (!int_out_urb) {
419                         retval = -ENOMEM;
420                         dbg("%s Unable to allocate urb ", __func__);
421                         goto error_no_urb;
422                 }
423                 buf = usb_buffer_alloc(dev->udev, dev->report_size,
424                                        GFP_KERNEL, &int_out_urb->transfer_dma);
425                 if (!buf) {
426                         retval = -ENOMEM;
427                         dbg("%s Unable to allocate buffer ", __func__);
428                         goto error_no_buffer;
429                 }
430                 usb_fill_int_urb(int_out_urb, dev->udev,
431                                  usb_sndintpipe(dev->udev,
432                                                 dev->int_out_endpoint->bEndpointAddress),
433                                  buf, dev->report_size,
434                                  iowarrior_write_callback, dev,
435                                  dev->int_out_endpoint->bInterval);
436                 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
437                 if (copy_from_user(buf, user_buffer, count)) {
438                         retval = -EFAULT;
439                         goto error;
440                 }
441                 retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
442                 if (retval) {
443                         dbg("%s submit error %d for urb nr.%d", __func__,
444                             retval, atomic_read(&dev->write_busy));
445                         goto error;
446                 }
447                 /* submit was ok */
448                 retval = count;
449                 usb_free_urb(int_out_urb);
450                 goto exit;
451                 break;
452         default:
453                 /* what do we have here ? An unsupported Product-ID ? */
454                 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x",
455                         __FUNCTION__, dev->product_id);
456                 retval = -EFAULT;
457                 goto exit;
458                 break;
459         }
460 error:
461         usb_buffer_free(dev->udev, dev->report_size, buf,
462                         int_out_urb->transfer_dma);
463 error_no_buffer:
464         usb_free_urb(int_out_urb);
465 error_no_urb:
466         atomic_dec(&dev->write_busy);
467         wake_up_interruptible(&dev->write_wait);
468 exit:
469         mutex_unlock(&dev->mutex);
470         return retval;
471 }
472
473 /**
474  *      iowarrior_ioctl
475  */
476 static int iowarrior_ioctl(struct inode *inode, struct file *file,
477                            unsigned int cmd, unsigned long arg)
478 {
479         struct iowarrior *dev = NULL;
480         __u8 *buffer;
481         __u8 __user *user_buffer;
482         int retval;
483         int io_res;             /* checks for bytes read/written and copy_to/from_user results */
484
485         dev = (struct iowarrior *)file->private_data;
486         if (dev == NULL) {
487                 return -ENODEV;
488         }
489
490         buffer = kzalloc(dev->report_size, GFP_KERNEL);
491         if (!buffer)
492                 return -ENOMEM;
493
494         /* lock this object */
495         mutex_lock(&dev->mutex);
496
497         /* verify that the device wasn't unplugged */
498         if (!dev->present) {
499                 retval = -ENODEV;
500                 goto error_out;
501         }
502
503         dbg("%s - minor %d, cmd 0x%.4x, arg %ld", __func__, dev->minor, cmd,
504             arg);
505
506         retval = 0;
507         io_res = 0;
508         switch (cmd) {
509         case IOW_WRITE:
510                 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
511                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
512                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
513                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
514                         user_buffer = (__u8 __user *)arg;
515                         io_res = copy_from_user(buffer, user_buffer,
516                                                 dev->report_size);
517                         if (io_res) {
518                                 retval = -EFAULT;
519                         } else {
520                                 io_res = usb_set_report(dev->interface, 2, 0,
521                                                         buffer,
522                                                         dev->report_size);
523                                 if (io_res < 0)
524                                         retval = io_res;
525                         }
526                 } else {
527                         retval = -EINVAL;
528                         dev_err(&dev->interface->dev,
529                                 "ioctl 'IOW_WRITE' is not supported for product=0x%x.",
530                                 dev->product_id);
531                 }
532                 break;
533         case IOW_READ:
534                 user_buffer = (__u8 __user *)arg;
535                 io_res = usb_get_report(dev->udev,
536                                         dev->interface->cur_altsetting, 1, 0,
537                                         buffer, dev->report_size);
538                 if (io_res < 0)
539                         retval = io_res;
540                 else {
541                         io_res = copy_to_user(user_buffer, buffer, dev->report_size);
542                         if (io_res < 0)
543                                 retval = -EFAULT;
544                 }
545                 break;
546         case IOW_GETINFO:
547                 {
548                         /* Report available information for the device */
549                         struct iowarrior_info info;
550                         /* needed for power consumption */
551                         struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
552
553                         /* directly from the descriptor */
554                         info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
555                         info.product = dev->product_id;
556                         info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
557
558                         /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
559                         info.speed = le16_to_cpu(dev->udev->speed);
560                         info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
561                         info.report_size = dev->report_size;
562
563                         /* serial number string has been read earlier 8 chars or empty string */
564                         memcpy(info.serial, dev->chip_serial,
565                                sizeof(dev->chip_serial));
566                         if (cfg_descriptor == NULL) {
567                                 info.power = -1;        /* no information available */
568                         } else {
569                                 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
570                                 info.power = cfg_descriptor->bMaxPower * 2;
571                         }
572                         io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
573                                          sizeof(struct iowarrior_info));
574                         if (io_res < 0)
575                                 retval = -EFAULT;
576                         break;
577                 }
578         default:
579                 /* return that we did not understand this ioctl call */
580                 retval = -ENOTTY;
581                 break;
582         }
583 error_out:
584         /* unlock the device */
585         mutex_unlock(&dev->mutex);
586         kfree(buffer);
587         return retval;
588 }
589
590 /**
591  *      iowarrior_open
592  */
593 static int iowarrior_open(struct inode *inode, struct file *file)
594 {
595         struct iowarrior *dev = NULL;
596         struct usb_interface *interface;
597         int subminor;
598         int retval = 0;
599
600         dbg("%s", __func__);
601
602         subminor = iminor(inode);
603
604         interface = usb_find_interface(&iowarrior_driver, subminor);
605         if (!interface) {
606                 err("%s - error, can't find device for minor %d", __FUNCTION__,
607                     subminor);
608                 return -ENODEV;
609         }
610
611         dev = usb_get_intfdata(interface);
612         if (!dev)
613                 return -ENODEV;
614
615         mutex_lock(&dev->mutex);
616
617         /* Only one process can open each device, no sharing. */
618         if (dev->opened) {
619                 retval = -EBUSY;
620                 goto out;
621         }
622
623         /* setup interrupt handler for receiving values */
624         if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
625                 dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
626                 retval = -EFAULT;
627                 goto out;
628         }
629         /* increment our usage count for the driver */
630         ++dev->opened;
631         /* save our object in the file's private structure */
632         file->private_data = dev;
633         retval = 0;
634
635 out:
636         mutex_unlock(&dev->mutex);
637         return retval;
638 }
639
640 /**
641  *      iowarrior_release
642  */
643 static int iowarrior_release(struct inode *inode, struct file *file)
644 {
645         struct iowarrior *dev;
646         int retval = 0;
647
648         dev = (struct iowarrior *)file->private_data;
649         if (dev == NULL) {
650                 return -ENODEV;
651         }
652
653         dbg("%s - minor %d", __func__, dev->minor);
654
655         /* lock our device */
656         mutex_lock(&dev->mutex);
657
658         if (dev->opened <= 0) {
659                 retval = -ENODEV;       /* close called more than once */
660                 mutex_unlock(&dev->mutex);
661         } else {
662                 dev->opened = 0;        /* we're closeing now */
663                 retval = 0;
664                 if (dev->present) {
665                         /*
666                            The device is still connected so we only shutdown
667                            pending read-/write-ops.
668                          */
669                         usb_kill_urb(dev->int_in_urb);
670                         wake_up_interruptible(&dev->read_wait);
671                         wake_up_interruptible(&dev->write_wait);
672                         mutex_unlock(&dev->mutex);
673                 } else {
674                         /* The device was unplugged, cleanup resources */
675                         mutex_unlock(&dev->mutex);
676                         iowarrior_delete(dev);
677                 }
678         }
679         return retval;
680 }
681
682 static unsigned iowarrior_poll(struct file *file, poll_table * wait)
683 {
684         struct iowarrior *dev = file->private_data;
685         unsigned int mask = 0;
686
687         if (!dev->present)
688                 return POLLERR | POLLHUP;
689
690         poll_wait(file, &dev->read_wait, wait);
691         poll_wait(file, &dev->write_wait, wait);
692
693         if (!dev->present)
694                 return POLLERR | POLLHUP;
695
696         if (read_index(dev) != -1)
697                 mask |= POLLIN | POLLRDNORM;
698
699         if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
700                 mask |= POLLOUT | POLLWRNORM;
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 struct file_operations iowarrior_fops = {
714         .owner = THIS_MODULE,
715         .write = iowarrior_write,
716         .read = iowarrior_read,
717         .ioctl = iowarrior_ioctl,
718         .open = iowarrior_open,
719         .release = iowarrior_release,
720         .poll = iowarrior_poll,
721 };
722
723 /*
724  * usb class driver info in order to get a minor number from the usb core,
725  * and to have the device registered with devfs and the driver core
726  */
727 static struct usb_class_driver iowarrior_class = {
728         .name = "iowarrior%d",
729         .fops = &iowarrior_fops,
730         .minor_base = IOWARRIOR_MINOR_BASE,
731 };
732
733 /*---------------------------------*/
734 /*  probe and disconnect functions */
735 /*---------------------------------*/
736 /**
737  *      iowarrior_probe
738  *
739  *      Called by the usb core when a new device is connected that it thinks
740  *      this driver might be interested in.
741  */
742 static int iowarrior_probe(struct usb_interface *interface,
743                            const struct usb_device_id *id)
744 {
745         struct usb_device *udev = interface_to_usbdev(interface);
746         struct iowarrior *dev = NULL;
747         struct usb_host_interface *iface_desc;
748         struct usb_endpoint_descriptor *endpoint;
749         int i;
750         int retval = -ENOMEM;
751
752         /* allocate memory for our device state and intialize it */
753         dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
754         if (dev == NULL) {
755                 dev_err(&interface->dev, "Out of memory");
756                 return retval;
757         }
758
759         mutex_init(&dev->mutex);
760
761         atomic_set(&dev->intr_idx, 0);
762         atomic_set(&dev->read_idx, 0);
763         spin_lock_init(&dev->intr_idx_lock);
764         atomic_set(&dev->overflow_flag, 0);
765         init_waitqueue_head(&dev->read_wait);
766         atomic_set(&dev->write_busy, 0);
767         init_waitqueue_head(&dev->write_wait);
768
769         dev->udev = udev;
770         dev->interface = interface;
771
772         iface_desc = interface->cur_altsetting;
773         dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
774
775         /* set up the endpoint information */
776         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
777                 endpoint = &iface_desc->endpoint[i].desc;
778
779                 if (usb_endpoint_is_int_in(endpoint))
780                         dev->int_in_endpoint = endpoint;
781                 if (usb_endpoint_is_int_out(endpoint))
782                         /* this one will match for the IOWarrior56 only */
783                         dev->int_out_endpoint = endpoint;
784         }
785         /* we have to check the report_size often, so remember it in the endianess suitable for our machine */
786         dev->report_size = le16_to_cpu(dev->int_in_endpoint->wMaxPacketSize);
787         if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&
788             (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56))
789                 /* IOWarrior56 has wMaxPacketSize different from report size */
790                 dev->report_size = 7;
791
792         /* create the urb and buffer for reading */
793         dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
794         if (!dev->int_in_urb) {
795                 dev_err(&interface->dev, "Couldn't allocate interrupt_in_urb\n");
796                 goto error;
797         }
798         dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
799         if (!dev->int_in_buffer) {
800                 dev_err(&interface->dev, "Couldn't allocate int_in_buffer\n");
801                 goto error;
802         }
803         usb_fill_int_urb(dev->int_in_urb, dev->udev,
804                          usb_rcvintpipe(dev->udev,
805                                         dev->int_in_endpoint->bEndpointAddress),
806                          dev->int_in_buffer, dev->report_size,
807                          iowarrior_callback, dev,
808                          dev->int_in_endpoint->bInterval);
809         /* create an internal buffer for interrupt data from the device */
810         dev->read_queue =
811             kmalloc(((dev->report_size + 1) * MAX_INTERRUPT_BUFFER),
812                     GFP_KERNEL);
813         if (!dev->read_queue) {
814                 dev_err(&interface->dev, "Couldn't allocate read_queue\n");
815                 goto error;
816         }
817         /* Get the serial-number of the chip */
818         memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
819         usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
820                    sizeof(dev->chip_serial));
821         if (strlen(dev->chip_serial) != 8)
822                 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
823
824         /* Set the idle timeout to 0, if this is interface 0 */
825         if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
826             usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
827                             0x0A,
828                             USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
829                             0, NULL, 0, USB_CTRL_SET_TIMEOUT);
830         }
831         /* allow device read and ioctl */
832         dev->present = 1;
833
834         /* we can register the device now, as it is ready */
835         usb_set_intfdata(interface, dev);
836
837         retval = usb_register_dev(interface, &iowarrior_class);
838         if (retval) {
839                 /* something prevented us from registering this driver */
840                 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
841                 usb_set_intfdata(interface, NULL);
842                 goto error;
843         }
844
845         dev->minor = interface->minor;
846
847         /* let the user know what node this device is now attached to */
848         dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
849                  "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
850                  iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
851         return retval;
852
853 error:
854         iowarrior_delete(dev);
855         return retval;
856 }
857
858 /**
859  *      iowarrior_disconnect
860  *
861  *      Called by the usb core when the device is removed from the system.
862  */
863 static void iowarrior_disconnect(struct usb_interface *interface)
864 {
865         struct iowarrior *dev;
866         int minor;
867
868         dev = usb_get_intfdata(interface);
869         usb_set_intfdata(interface, NULL);
870
871         minor = dev->minor;
872
873         /* give back our minor */
874         usb_deregister_dev(interface, &iowarrior_class);
875
876         mutex_lock(&dev->mutex);
877
878         /* prevent device read, write and ioctl */
879         dev->present = 0;
880
881         mutex_unlock(&dev->mutex);
882
883         if (dev->opened) {
884                 /* There is a process that holds a filedescriptor to the device ,
885                    so we only shutdown read-/write-ops going on.
886                    Deleting the device is postponed until close() was called.
887                  */
888                 usb_kill_urb(dev->int_in_urb);
889                 wake_up_interruptible(&dev->read_wait);
890                 wake_up_interruptible(&dev->write_wait);
891         } else {
892                 /* no process is using the device, cleanup now */
893                 iowarrior_delete(dev);
894         }
895
896         dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
897                  minor - IOWARRIOR_MINOR_BASE);
898 }
899
900 /* usb specific object needed to register this driver with the usb subsystem */
901 static struct usb_driver iowarrior_driver = {
902         .name = "iowarrior",
903         .probe = iowarrior_probe,
904         .disconnect = iowarrior_disconnect,
905         .id_table = iowarrior_ids,
906 };
907
908 static int __init iowarrior_init(void)
909 {
910         return usb_register(&iowarrior_driver);
911 }
912
913 static void __exit iowarrior_exit(void)
914 {
915         usb_deregister(&iowarrior_driver);
916 }
917
918 module_init(iowarrior_init);
919 module_exit(iowarrior_exit);