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v3.1
 
  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/mutex.h>
 22#include <linux/poll.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 official 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 DEFINE_MUTEX(iowarrior_mutex);
 65static int debug = 0;
 66module_param(debug, bool, 0644);
 67MODULE_PARM_DESC(debug, "debug=1 enables debugging messages");
 68
 69static struct usb_driver iowarrior_driver;
 70static DEFINE_MUTEX(iowarrior_open_disc_lock);
 71
 72/*--------------*/
 73/*     data     */
 74/*--------------*/
 75
 76/* Structure to hold all of our device specific stuff */
 77struct iowarrior {
 78	struct mutex mutex;			/* locks this structure */
 79	struct usb_device *udev;		/* save off the usb device pointer */
 80	struct usb_interface *interface;	/* the interface for this device */
 81	unsigned char minor;			/* the starting minor number for this device */
 82	struct usb_endpoint_descriptor *int_out_endpoint;	/* endpoint for reading (needed for IOW56 only) */
 83	struct usb_endpoint_descriptor *int_in_endpoint;	/* endpoint for reading */
 84	struct urb *int_in_urb;		/* the urb for reading data */
 85	unsigned char *int_in_buffer;	/* buffer for data to be read */
 86	unsigned char serial_number;	/* to detect lost packages */
 87	unsigned char *read_queue;	/* size is MAX_INTERRUPT_BUFFER * packet size */
 88	wait_queue_head_t read_wait;
 89	wait_queue_head_t write_wait;	/* wait-queue for writing to the device */
 90	atomic_t write_busy;		/* number of write-urbs submitted */
 91	atomic_t read_idx;
 92	atomic_t intr_idx;
 93	spinlock_t intr_idx_lock;	/* protects intr_idx */
 94	atomic_t overflow_flag;		/* signals an index 'rollover' */
 95	int present;			/* this is 1 as long as the device is connected */
 96	int opened;			/* this is 1 if the device is currently open */
 97	char chip_serial[9];		/* the serial number string of the chip connected */
 98	int report_size;		/* number of bytes in a report */
 99	u16 product_id;
 
100};
101
102/*--------------*/
103/*    globals   */
104/*--------------*/
105
106/*
107 *  USB spec identifies 5 second timeouts.
108 */
109#define GET_TIMEOUT 5
110#define USB_REQ_GET_REPORT  0x01
111//#if 0
112static int usb_get_report(struct usb_device *dev,
113			  struct usb_host_interface *inter, unsigned char type,
114			  unsigned char id, void *buf, int size)
115{
116	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
117			       USB_REQ_GET_REPORT,
118			       USB_DIR_IN | USB_TYPE_CLASS |
119			       USB_RECIP_INTERFACE, (type << 8) + id,
120			       inter->desc.bInterfaceNumber, buf, size,
121			       GET_TIMEOUT*HZ);
122}
123//#endif
124
125#define USB_REQ_SET_REPORT 0x09
126
127static int usb_set_report(struct usb_interface *intf, unsigned char type,
128			  unsigned char id, void *buf, int size)
129{
130	return usb_control_msg(interface_to_usbdev(intf),
131			       usb_sndctrlpipe(interface_to_usbdev(intf), 0),
132			       USB_REQ_SET_REPORT,
133			       USB_TYPE_CLASS | USB_RECIP_INTERFACE,
134			       (type << 8) + id,
135			       intf->cur_altsetting->desc.bInterfaceNumber, buf,
136			       size, HZ);
137}
138
139/*---------------------*/
140/* driver registration */
141/*---------------------*/
142/* table of devices that work with this driver */
143static const struct usb_device_id iowarrior_ids[] = {
144	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
145	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
146	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
147	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
148	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
149	{}			/* Terminating entry */
150};
151MODULE_DEVICE_TABLE(usb, iowarrior_ids);
152
153/*
154 * USB callback handler for reading data
155 */
156static void iowarrior_callback(struct urb *urb)
157{
158	struct iowarrior *dev = urb->context;
159	int intr_idx;
160	int read_idx;
161	int aux_idx;
162	int offset;
163	int status = urb->status;
164	int retval;
165
166	switch (status) {
167	case 0:
168		/* success */
169		break;
170	case -ECONNRESET:
171	case -ENOENT:
172	case -ESHUTDOWN:
173		return;
174	default:
175		goto exit;
176	}
177
178	spin_lock(&dev->intr_idx_lock);
179	intr_idx = atomic_read(&dev->intr_idx);
180	/* aux_idx become previous intr_idx */
181	aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
182	read_idx = atomic_read(&dev->read_idx);
183
184	/* queue is not empty and it's interface 0 */
185	if ((intr_idx != read_idx)
186	    && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
187		/* + 1 for serial number */
188		offset = aux_idx * (dev->report_size + 1);
189		if (!memcmp
190		    (dev->read_queue + offset, urb->transfer_buffer,
191		     dev->report_size)) {
192			/* equal values on interface 0 will be ignored */
193			spin_unlock(&dev->intr_idx_lock);
194			goto exit;
195		}
196	}
197
198	/* aux_idx become next intr_idx */
199	aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
200	if (read_idx == aux_idx) {
201		/* queue full, dropping oldest input */
202		read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
203		atomic_set(&dev->read_idx, read_idx);
204		atomic_set(&dev->overflow_flag, 1);
205	}
206
207	/* +1 for serial number */
208	offset = intr_idx * (dev->report_size + 1);
209	memcpy(dev->read_queue + offset, urb->transfer_buffer,
210	       dev->report_size);
211	*(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
212
213	atomic_set(&dev->intr_idx, aux_idx);
214	spin_unlock(&dev->intr_idx_lock);
215	/* tell the blocking read about the new data */
216	wake_up_interruptible(&dev->read_wait);
217
218exit:
219	retval = usb_submit_urb(urb, GFP_ATOMIC);
220	if (retval)
221		dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n",
222			__func__, retval);
223
224}
225
226/*
227 * USB Callback handler for write-ops
228 */
229static void iowarrior_write_callback(struct urb *urb)
230{
231	struct iowarrior *dev;
232	int status = urb->status;
233
234	dev = urb->context;
235	/* sync/async unlink faults aren't errors */
236	if (status &&
237	    !(status == -ENOENT ||
238	      status == -ECONNRESET || status == -ESHUTDOWN)) {
239		dbg("%s - nonzero write bulk status received: %d",
240		    __func__, status);
241	}
242	/* free up our allocated buffer */
243	usb_free_coherent(urb->dev, urb->transfer_buffer_length,
244			  urb->transfer_buffer, urb->transfer_dma);
245	/* tell a waiting writer the interrupt-out-pipe is available again */
246	atomic_dec(&dev->write_busy);
247	wake_up_interruptible(&dev->write_wait);
248}
249
250/**
251 *	iowarrior_delete
252 */
253static inline void iowarrior_delete(struct iowarrior *dev)
254{
255	dbg("%s - minor %d", __func__, dev->minor);
256	kfree(dev->int_in_buffer);
257	usb_free_urb(dev->int_in_urb);
258	kfree(dev->read_queue);
 
259	kfree(dev);
260}
261
262/*---------------------*/
263/* fops implementation */
264/*---------------------*/
265
266static int read_index(struct iowarrior *dev)
267{
268	int intr_idx, read_idx;
269
270	read_idx = atomic_read(&dev->read_idx);
271	intr_idx = atomic_read(&dev->intr_idx);
272
273	return (read_idx == intr_idx ? -1 : read_idx);
274}
275
276/**
277 *  iowarrior_read
278 */
279static ssize_t iowarrior_read(struct file *file, char __user *buffer,
280			      size_t count, loff_t *ppos)
281{
282	struct iowarrior *dev;
283	int read_idx;
284	int offset;
285
286	dev = file->private_data;
287
288	/* verify that the device wasn't unplugged */
289	if (dev == NULL || !dev->present)
290		return -ENODEV;
291
292	dbg("%s - minor %d, count = %zd", __func__, dev->minor, count);
 
293
294	/* read count must be packet size (+ time stamp) */
295	if ((count != dev->report_size)
296	    && (count != (dev->report_size + 1)))
297		return -EINVAL;
298
299	/* repeat until no buffer overrun in callback handler occur */
300	do {
301		atomic_set(&dev->overflow_flag, 0);
302		if ((read_idx = read_index(dev)) == -1) {
303			/* queue emty */
304			if (file->f_flags & O_NONBLOCK)
305				return -EAGAIN;
306			else {
307				//next line will return when there is either new data, or the device is unplugged
308				int r = wait_event_interruptible(dev->read_wait,
309								 (!dev->present
310								  || (read_idx =
311								      read_index
312								      (dev)) !=
313								  -1));
314				if (r) {
315					//we were interrupted by a signal
316					return -ERESTART;
317				}
318				if (!dev->present) {
319					//The device was unplugged
320					return -ENODEV;
321				}
322				if (read_idx == -1) {
323					// Can this happen ???
324					return 0;
325				}
326			}
327		}
328
329		offset = read_idx * (dev->report_size + 1);
330		if (copy_to_user(buffer, dev->read_queue + offset, count)) {
331			return -EFAULT;
332		}
333	} while (atomic_read(&dev->overflow_flag));
334
335	read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
336	atomic_set(&dev->read_idx, read_idx);
337	return count;
338}
339
340/*
341 * iowarrior_write
342 */
343static ssize_t iowarrior_write(struct file *file,
344			       const char __user *user_buffer,
345			       size_t count, loff_t *ppos)
346{
347	struct iowarrior *dev;
348	int retval = 0;
349	char *buf = NULL;	/* for IOW24 and IOW56 we need a buffer */
350	struct urb *int_out_urb = NULL;
351
352	dev = file->private_data;
353
354	mutex_lock(&dev->mutex);
355	/* verify that the device wasn't unplugged */
356	if (!dev->present) {
357		retval = -ENODEV;
358		goto exit;
359	}
360	dbg("%s - minor %d, count = %zd", __func__, dev->minor, count);
 
361	/* if count is 0 we're already done */
362	if (count == 0) {
363		retval = 0;
364		goto exit;
365	}
366	/* We only accept full reports */
367	if (count != dev->report_size) {
368		retval = -EINVAL;
369		goto exit;
370	}
371	switch (dev->product_id) {
372	case USB_DEVICE_ID_CODEMERCS_IOW24:
373	case USB_DEVICE_ID_CODEMERCS_IOWPV1:
374	case USB_DEVICE_ID_CODEMERCS_IOWPV2:
375	case USB_DEVICE_ID_CODEMERCS_IOW40:
376		/* IOW24 and IOW40 use a synchronous call */
377		buf = kmalloc(count, GFP_KERNEL);
378		if (!buf) {
379			retval = -ENOMEM;
380			goto exit;
381		}
382		if (copy_from_user(buf, user_buffer, count)) {
383			retval = -EFAULT;
384			kfree(buf);
385			goto exit;
386		}
387		retval = usb_set_report(dev->interface, 2, 0, buf, count);
388		kfree(buf);
389		goto exit;
390		break;
391	case USB_DEVICE_ID_CODEMERCS_IOW56:
392		/* The IOW56 uses asynchronous IO and more urbs */
393		if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
394			/* Wait until we are below the limit for submitted urbs */
395			if (file->f_flags & O_NONBLOCK) {
396				retval = -EAGAIN;
397				goto exit;
398			} else {
399				retval = wait_event_interruptible(dev->write_wait,
400								  (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
401				if (retval) {
402					/* we were interrupted by a signal */
403					retval = -ERESTART;
404					goto exit;
405				}
406				if (!dev->present) {
407					/* The device was unplugged */
408					retval = -ENODEV;
409					goto exit;
410				}
411				if (!dev->opened) {
412					/* We were closed while waiting for an URB */
413					retval = -ENODEV;
414					goto exit;
415				}
416			}
417		}
418		atomic_inc(&dev->write_busy);
419		int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
420		if (!int_out_urb) {
421			retval = -ENOMEM;
422			dbg("%s Unable to allocate urb ", __func__);
423			goto error_no_urb;
424		}
425		buf = usb_alloc_coherent(dev->udev, dev->report_size,
426					 GFP_KERNEL, &int_out_urb->transfer_dma);
427		if (!buf) {
428			retval = -ENOMEM;
429			dbg("%s Unable to allocate buffer ", __func__);
 
430			goto error_no_buffer;
431		}
432		usb_fill_int_urb(int_out_urb, dev->udev,
433				 usb_sndintpipe(dev->udev,
434						dev->int_out_endpoint->bEndpointAddress),
435				 buf, dev->report_size,
436				 iowarrior_write_callback, dev,
437				 dev->int_out_endpoint->bInterval);
438		int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
439		if (copy_from_user(buf, user_buffer, count)) {
440			retval = -EFAULT;
441			goto error;
442		}
 
443		retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
444		if (retval) {
445			dbg("%s submit error %d for urb nr.%d", __func__,
446			    retval, atomic_read(&dev->write_busy));
 
 
447			goto error;
448		}
449		/* submit was ok */
450		retval = count;
451		usb_free_urb(int_out_urb);
452		goto exit;
453		break;
454	default:
455		/* what do we have here ? An unsupported Product-ID ? */
456		dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n",
457			__func__, dev->product_id);
458		retval = -EFAULT;
459		goto exit;
460		break;
461	}
462error:
463	usb_free_coherent(dev->udev, dev->report_size, buf,
464			  int_out_urb->transfer_dma);
465error_no_buffer:
466	usb_free_urb(int_out_urb);
467error_no_urb:
468	atomic_dec(&dev->write_busy);
469	wake_up_interruptible(&dev->write_wait);
470exit:
471	mutex_unlock(&dev->mutex);
472	return retval;
473}
474
475/**
476 *	iowarrior_ioctl
477 */
478static long iowarrior_ioctl(struct file *file, unsigned int cmd,
479							unsigned long arg)
480{
481	struct iowarrior *dev = NULL;
482	__u8 *buffer;
483	__u8 __user *user_buffer;
484	int retval;
485	int io_res;		/* checks for bytes read/written and copy_to/from_user results */
486
487	dev = file->private_data;
488	if (dev == NULL) {
489		return -ENODEV;
490	}
491
492	buffer = kzalloc(dev->report_size, GFP_KERNEL);
493	if (!buffer)
494		return -ENOMEM;
495
496	/* lock this object */
497	mutex_lock(&iowarrior_mutex);
498	mutex_lock(&dev->mutex);
499
500	/* verify that the device wasn't unplugged */
501	if (!dev->present) {
502		retval = -ENODEV;
503		goto error_out;
504	}
505
506	dbg("%s - minor %d, cmd 0x%.4x, arg %ld", __func__, dev->minor, cmd,
507	    arg);
508
509	retval = 0;
510	io_res = 0;
511	switch (cmd) {
512	case IOW_WRITE:
513		if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
514		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
515		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
516		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
517			user_buffer = (__u8 __user *)arg;
518			io_res = copy_from_user(buffer, user_buffer,
519						dev->report_size);
520			if (io_res) {
521				retval = -EFAULT;
522			} else {
523				io_res = usb_set_report(dev->interface, 2, 0,
524							buffer,
525							dev->report_size);
526				if (io_res < 0)
527					retval = io_res;
528			}
529		} else {
530			retval = -EINVAL;
531			dev_err(&dev->interface->dev,
532				"ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
533				dev->product_id);
534		}
535		break;
536	case IOW_READ:
537		user_buffer = (__u8 __user *)arg;
538		io_res = usb_get_report(dev->udev,
539					dev->interface->cur_altsetting, 1, 0,
540					buffer, dev->report_size);
541		if (io_res < 0)
542			retval = io_res;
543		else {
544			io_res = copy_to_user(user_buffer, buffer, dev->report_size);
545			if (io_res)
546				retval = -EFAULT;
547		}
548		break;
549	case IOW_GETINFO:
550		{
551			/* Report available information for the device */
552			struct iowarrior_info info;
553			/* needed for power consumption */
554			struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
555
556			memset(&info, 0, sizeof(info));
557			/* directly from the descriptor */
558			info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
559			info.product = dev->product_id;
560			info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
561
562			/* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
563			info.speed = le16_to_cpu(dev->udev->speed);
564			info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
565			info.report_size = dev->report_size;
566
567			/* serial number string has been read earlier 8 chars or empty string */
568			memcpy(info.serial, dev->chip_serial,
569			       sizeof(dev->chip_serial));
570			if (cfg_descriptor == NULL) {
571				info.power = -1;	/* no information available */
572			} else {
573				/* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
574				info.power = cfg_descriptor->bMaxPower * 2;
575			}
576			io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
577					 sizeof(struct iowarrior_info));
578			if (io_res)
579				retval = -EFAULT;
580			break;
581		}
582	default:
583		/* return that we did not understand this ioctl call */
584		retval = -ENOTTY;
585		break;
586	}
587error_out:
588	/* unlock the device */
589	mutex_unlock(&dev->mutex);
590	mutex_unlock(&iowarrior_mutex);
591	kfree(buffer);
592	return retval;
593}
594
595/**
596 *	iowarrior_open
597 */
598static int iowarrior_open(struct inode *inode, struct file *file)
599{
600	struct iowarrior *dev = NULL;
601	struct usb_interface *interface;
602	int subminor;
603	int retval = 0;
604
605	dbg("%s", __func__);
606
607	mutex_lock(&iowarrior_mutex);
608	subminor = iminor(inode);
609
610	interface = usb_find_interface(&iowarrior_driver, subminor);
611	if (!interface) {
612		mutex_unlock(&iowarrior_mutex);
613		err("%s - error, can't find device for minor %d", __func__,
614		    subminor);
615		return -ENODEV;
616	}
617
618	mutex_lock(&iowarrior_open_disc_lock);
619	dev = usb_get_intfdata(interface);
620	if (!dev) {
621		mutex_unlock(&iowarrior_open_disc_lock);
622		mutex_unlock(&iowarrior_mutex);
623		return -ENODEV;
624	}
625
626	mutex_lock(&dev->mutex);
627	mutex_unlock(&iowarrior_open_disc_lock);
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	/* save our object in the file's private structure */
644	file->private_data = dev;
645	retval = 0;
646
647out:
648	mutex_unlock(&dev->mutex);
649	mutex_unlock(&iowarrior_mutex);
650	return retval;
651}
652
653/**
654 *	iowarrior_release
655 */
656static int iowarrior_release(struct inode *inode, struct file *file)
657{
658	struct iowarrior *dev;
659	int retval = 0;
660
661	dev = file->private_data;
662	if (dev == NULL) {
663		return -ENODEV;
664	}
665
666	dbg("%s - minor %d", __func__, dev->minor);
667
668	/* lock our device */
669	mutex_lock(&dev->mutex);
670
671	if (dev->opened <= 0) {
672		retval = -ENODEV;	/* close called more than once */
673		mutex_unlock(&dev->mutex);
674	} else {
675		dev->opened = 0;	/* we're closeing now */
676		retval = 0;
677		if (dev->present) {
678			/*
679			   The device is still connected so we only shutdown
680			   pending read-/write-ops.
681			 */
682			usb_kill_urb(dev->int_in_urb);
683			wake_up_interruptible(&dev->read_wait);
684			wake_up_interruptible(&dev->write_wait);
685			mutex_unlock(&dev->mutex);
686		} else {
687			/* The device was unplugged, cleanup resources */
688			mutex_unlock(&dev->mutex);
689			iowarrior_delete(dev);
690		}
691	}
692	return retval;
693}
694
695static unsigned iowarrior_poll(struct file *file, poll_table * wait)
696{
697	struct iowarrior *dev = file->private_data;
698	unsigned int mask = 0;
699
700	if (!dev->present)
701		return POLLERR | POLLHUP;
702
703	poll_wait(file, &dev->read_wait, wait);
704	poll_wait(file, &dev->write_wait, wait);
705
706	if (!dev->present)
707		return POLLERR | POLLHUP;
708
709	if (read_index(dev) != -1)
710		mask |= POLLIN | POLLRDNORM;
711
712	if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
713		mask |= POLLOUT | POLLWRNORM;
714	return mask;
715}
716
717/*
718 * File operations needed when we register this driver.
719 * This assumes that this driver NEEDS file operations,
720 * of course, which means that the driver is expected
721 * to have a node in the /dev directory. If the USB
722 * device were for a network interface then the driver
723 * would use "struct net_driver" instead, and a serial
724 * device would use "struct tty_driver".
725 */
726static const struct file_operations iowarrior_fops = {
727	.owner = THIS_MODULE,
728	.write = iowarrior_write,
729	.read = iowarrior_read,
730	.unlocked_ioctl = iowarrior_ioctl,
731	.open = iowarrior_open,
732	.release = iowarrior_release,
733	.poll = iowarrior_poll,
734	.llseek = noop_llseek,
735};
736
737static char *iowarrior_devnode(struct device *dev, mode_t *mode)
738{
739	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
740}
741
742/*
743 * usb class driver info in order to get a minor number from the usb core,
744 * and to have the device registered with devfs and the driver core
745 */
746static struct usb_class_driver iowarrior_class = {
747	.name = "iowarrior%d",
748	.devnode = iowarrior_devnode,
749	.fops = &iowarrior_fops,
750	.minor_base = IOWARRIOR_MINOR_BASE,
751};
752
753/*---------------------------------*/
754/*  probe and disconnect functions */
755/*---------------------------------*/
756/**
757 *	iowarrior_probe
758 *
759 *	Called by the usb core when a new device is connected that it thinks
760 *	this driver might be interested in.
761 */
762static int iowarrior_probe(struct usb_interface *interface,
763			   const struct usb_device_id *id)
764{
765	struct usb_device *udev = interface_to_usbdev(interface);
766	struct iowarrior *dev = NULL;
767	struct usb_host_interface *iface_desc;
768	struct usb_endpoint_descriptor *endpoint;
769	int i;
770	int retval = -ENOMEM;
 
771
772	/* allocate memory for our device state and initialize it */
773	dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
774	if (dev == NULL) {
775		dev_err(&interface->dev, "Out of memory\n");
776		return retval;
777	}
778
779	mutex_init(&dev->mutex);
780
781	atomic_set(&dev->intr_idx, 0);
782	atomic_set(&dev->read_idx, 0);
783	spin_lock_init(&dev->intr_idx_lock);
784	atomic_set(&dev->overflow_flag, 0);
785	init_waitqueue_head(&dev->read_wait);
786	atomic_set(&dev->write_busy, 0);
787	init_waitqueue_head(&dev->write_wait);
788
789	dev->udev = udev;
790	dev->interface = interface;
791
792	iface_desc = interface->cur_altsetting;
793	dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
794
795	/* set up the endpoint information */
796	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
797		endpoint = &iface_desc->endpoint[i].desc;
798
799		if (usb_endpoint_is_int_in(endpoint))
800			dev->int_in_endpoint = endpoint;
801		if (usb_endpoint_is_int_out(endpoint))
802			/* this one will match for the IOWarrior56 only */
803			dev->int_out_endpoint = endpoint;
 
 
 
 
 
 
 
 
804	}
805	/* we have to check the report_size often, so remember it in the endianess suitable for our machine */
806	dev->report_size = le16_to_cpu(dev->int_in_endpoint->wMaxPacketSize);
 
807	if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&
808	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56))
809		/* IOWarrior56 has wMaxPacketSize different from report size */
810		dev->report_size = 7;
811
812	/* create the urb and buffer for reading */
813	dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
814	if (!dev->int_in_urb) {
815		dev_err(&interface->dev, "Couldn't allocate interrupt_in_urb\n");
816		goto error;
817	}
818	dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
819	if (!dev->int_in_buffer) {
820		dev_err(&interface->dev, "Couldn't allocate int_in_buffer\n");
821		goto error;
822	}
823	usb_fill_int_urb(dev->int_in_urb, dev->udev,
824			 usb_rcvintpipe(dev->udev,
825					dev->int_in_endpoint->bEndpointAddress),
826			 dev->int_in_buffer, dev->report_size,
827			 iowarrior_callback, dev,
828			 dev->int_in_endpoint->bInterval);
829	/* create an internal buffer for interrupt data from the device */
830	dev->read_queue =
831	    kmalloc(((dev->report_size + 1) * MAX_INTERRUPT_BUFFER),
832		    GFP_KERNEL);
833	if (!dev->read_queue) {
834		dev_err(&interface->dev, "Couldn't allocate read_queue\n");
835		goto error;
836	}
837	/* Get the serial-number of the chip */
838	memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
839	usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
840		   sizeof(dev->chip_serial));
841	if (strlen(dev->chip_serial) != 8)
842		memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
843
844	/* Set the idle timeout to 0, if this is interface 0 */
845	if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
846	    usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
847			    0x0A,
848			    USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
849			    0, NULL, 0, USB_CTRL_SET_TIMEOUT);
850	}
851	/* allow device read and ioctl */
852	dev->present = 1;
853
854	/* we can register the device now, as it is ready */
855	usb_set_intfdata(interface, dev);
856
857	retval = usb_register_dev(interface, &iowarrior_class);
858	if (retval) {
859		/* something prevented us from registering this driver */
860		dev_err(&interface->dev, "Not able to get a minor for this device.\n");
861		usb_set_intfdata(interface, NULL);
862		goto error;
863	}
864
865	dev->minor = interface->minor;
866
867	/* let the user know what node this device is now attached to */
868	dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
869		 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
870		 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
871	return retval;
872
873error:
874	iowarrior_delete(dev);
875	return retval;
876}
877
878/**
879 *	iowarrior_disconnect
880 *
881 *	Called by the usb core when the device is removed from the system.
882 */
883static void iowarrior_disconnect(struct usb_interface *interface)
884{
885	struct iowarrior *dev;
886	int minor;
887
888	dev = usb_get_intfdata(interface);
889	mutex_lock(&iowarrior_open_disc_lock);
890	usb_set_intfdata(interface, NULL);
891
892	minor = dev->minor;
893
894	/* give back our minor */
895	usb_deregister_dev(interface, &iowarrior_class);
896
897	mutex_lock(&dev->mutex);
898
899	/* prevent device read, write and ioctl */
900	dev->present = 0;
901
902	mutex_unlock(&dev->mutex);
903	mutex_unlock(&iowarrior_open_disc_lock);
904
905	if (dev->opened) {
906		/* There is a process that holds a filedescriptor to the device ,
907		   so we only shutdown read-/write-ops going on.
908		   Deleting the device is postponed until close() was called.
909		 */
910		usb_kill_urb(dev->int_in_urb);
 
911		wake_up_interruptible(&dev->read_wait);
912		wake_up_interruptible(&dev->write_wait);
 
913	} else {
914		/* no process is using the device, cleanup now */
 
915		iowarrior_delete(dev);
916	}
917
918	dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
919		 minor - IOWARRIOR_MINOR_BASE);
920}
921
922/* usb specific object needed to register this driver with the usb subsystem */
923static struct usb_driver iowarrior_driver = {
924	.name = "iowarrior",
925	.probe = iowarrior_probe,
926	.disconnect = iowarrior_disconnect,
927	.id_table = iowarrior_ids,
928};
929
930static int __init iowarrior_init(void)
931{
932	return usb_register(&iowarrior_driver);
933}
934
935static void __exit iowarrior_exit(void)
936{
937	usb_deregister(&iowarrior_driver);
938}
939
940module_init(iowarrior_init);
941module_exit(iowarrior_exit);
v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  Native support for the I/O-Warrior USB devices
  4 *
  5 *  Copyright (c) 2003-2005  Code Mercenaries GmbH
  6 *  written by Christian Lucht <lucht@codemercs.com>
  7 *
  8 *  based on
  9
 10 *  usb-skeleton.c by Greg Kroah-Hartman  <greg@kroah.com>
 11 *  brlvger.c by Stephane Dalton  <sdalton@videotron.ca>
 12 *           and St�hane Doyon   <s.doyon@videotron.ca>
 13 *
 14 *  Released under the GPLv2.
 15 */
 16
 17#include <linux/module.h>
 18#include <linux/usb.h>
 
 19#include <linux/slab.h>
 20#include <linux/sched.h>
 21#include <linux/mutex.h>
 22#include <linux/poll.h>
 23#include <linux/usb/iowarrior.h>
 24
 
 
 25#define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
 26#define DRIVER_DESC "USB IO-Warrior driver"
 27
 28#define USB_VENDOR_ID_CODEMERCS		1984
 29/* low speed iowarrior */
 30#define USB_DEVICE_ID_CODEMERCS_IOW40	0x1500
 31#define USB_DEVICE_ID_CODEMERCS_IOW24	0x1501
 32#define USB_DEVICE_ID_CODEMERCS_IOWPV1	0x1511
 33#define USB_DEVICE_ID_CODEMERCS_IOWPV2	0x1512
 34/* full speed iowarrior */
 35#define USB_DEVICE_ID_CODEMERCS_IOW56	0x1503
 36
 37/* Get a minor range for your devices from the usb maintainer */
 38#ifdef CONFIG_USB_DYNAMIC_MINORS
 39#define IOWARRIOR_MINOR_BASE	0
 40#else
 41#define IOWARRIOR_MINOR_BASE	208	// SKELETON_MINOR_BASE 192 + 16, not official yet
 42#endif
 43
 44/* interrupt input queue size */
 45#define MAX_INTERRUPT_BUFFER 16
 46/*
 47   maximum number of urbs that are submitted for writes at the same time,
 48   this applies to the IOWarrior56 only!
 49   IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
 50*/
 51#define MAX_WRITES_IN_FLIGHT 4
 52
 
 
 
 
 53MODULE_AUTHOR(DRIVER_AUTHOR);
 54MODULE_DESCRIPTION(DRIVER_DESC);
 55MODULE_LICENSE("GPL");
 56
 
 
 
 
 
 
 57static struct usb_driver iowarrior_driver;
 
 58
 59/*--------------*/
 60/*     data     */
 61/*--------------*/
 62
 63/* Structure to hold all of our device specific stuff */
 64struct iowarrior {
 65	struct mutex mutex;			/* locks this structure */
 66	struct usb_device *udev;		/* save off the usb device pointer */
 67	struct usb_interface *interface;	/* the interface for this device */
 68	unsigned char minor;			/* the starting minor number for this device */
 69	struct usb_endpoint_descriptor *int_out_endpoint;	/* endpoint for reading (needed for IOW56 only) */
 70	struct usb_endpoint_descriptor *int_in_endpoint;	/* endpoint for reading */
 71	struct urb *int_in_urb;		/* the urb for reading data */
 72	unsigned char *int_in_buffer;	/* buffer for data to be read */
 73	unsigned char serial_number;	/* to detect lost packages */
 74	unsigned char *read_queue;	/* size is MAX_INTERRUPT_BUFFER * packet size */
 75	wait_queue_head_t read_wait;
 76	wait_queue_head_t write_wait;	/* wait-queue for writing to the device */
 77	atomic_t write_busy;		/* number of write-urbs submitted */
 78	atomic_t read_idx;
 79	atomic_t intr_idx;
 
 80	atomic_t overflow_flag;		/* signals an index 'rollover' */
 81	int present;			/* this is 1 as long as the device is connected */
 82	int opened;			/* this is 1 if the device is currently open */
 83	char chip_serial[9];		/* the serial number string of the chip connected */
 84	int report_size;		/* number of bytes in a report */
 85	u16 product_id;
 86	struct usb_anchor submitted;
 87};
 88
 89/*--------------*/
 90/*    globals   */
 91/*--------------*/
 92
 93/*
 94 *  USB spec identifies 5 second timeouts.
 95 */
 96#define GET_TIMEOUT 5
 97#define USB_REQ_GET_REPORT  0x01
 98//#if 0
 99static int usb_get_report(struct usb_device *dev,
100			  struct usb_host_interface *inter, unsigned char type,
101			  unsigned char id, void *buf, int size)
102{
103	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
104			       USB_REQ_GET_REPORT,
105			       USB_DIR_IN | USB_TYPE_CLASS |
106			       USB_RECIP_INTERFACE, (type << 8) + id,
107			       inter->desc.bInterfaceNumber, buf, size,
108			       GET_TIMEOUT*HZ);
109}
110//#endif
111
112#define USB_REQ_SET_REPORT 0x09
113
114static int usb_set_report(struct usb_interface *intf, unsigned char type,
115			  unsigned char id, void *buf, int size)
116{
117	return usb_control_msg(interface_to_usbdev(intf),
118			       usb_sndctrlpipe(interface_to_usbdev(intf), 0),
119			       USB_REQ_SET_REPORT,
120			       USB_TYPE_CLASS | USB_RECIP_INTERFACE,
121			       (type << 8) + id,
122			       intf->cur_altsetting->desc.bInterfaceNumber, buf,
123			       size, HZ);
124}
125
126/*---------------------*/
127/* driver registration */
128/*---------------------*/
129/* table of devices that work with this driver */
130static const struct usb_device_id iowarrior_ids[] = {
131	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
132	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
133	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
134	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
135	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
136	{}			/* Terminating entry */
137};
138MODULE_DEVICE_TABLE(usb, iowarrior_ids);
139
140/*
141 * USB callback handler for reading data
142 */
143static void iowarrior_callback(struct urb *urb)
144{
145	struct iowarrior *dev = urb->context;
146	int intr_idx;
147	int read_idx;
148	int aux_idx;
149	int offset;
150	int status = urb->status;
151	int retval;
152
153	switch (status) {
154	case 0:
155		/* success */
156		break;
157	case -ECONNRESET:
158	case -ENOENT:
159	case -ESHUTDOWN:
160		return;
161	default:
162		goto exit;
163	}
164
 
165	intr_idx = atomic_read(&dev->intr_idx);
166	/* aux_idx become previous intr_idx */
167	aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
168	read_idx = atomic_read(&dev->read_idx);
169
170	/* queue is not empty and it's interface 0 */
171	if ((intr_idx != read_idx)
172	    && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
173		/* + 1 for serial number */
174		offset = aux_idx * (dev->report_size + 1);
175		if (!memcmp
176		    (dev->read_queue + offset, urb->transfer_buffer,
177		     dev->report_size)) {
178			/* equal values on interface 0 will be ignored */
 
179			goto exit;
180		}
181	}
182
183	/* aux_idx become next intr_idx */
184	aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
185	if (read_idx == aux_idx) {
186		/* queue full, dropping oldest input */
187		read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
188		atomic_set(&dev->read_idx, read_idx);
189		atomic_set(&dev->overflow_flag, 1);
190	}
191
192	/* +1 for serial number */
193	offset = intr_idx * (dev->report_size + 1);
194	memcpy(dev->read_queue + offset, urb->transfer_buffer,
195	       dev->report_size);
196	*(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
197
198	atomic_set(&dev->intr_idx, aux_idx);
 
199	/* tell the blocking read about the new data */
200	wake_up_interruptible(&dev->read_wait);
201
202exit:
203	retval = usb_submit_urb(urb, GFP_ATOMIC);
204	if (retval)
205		dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n",
206			__func__, retval);
207
208}
209
210/*
211 * USB Callback handler for write-ops
212 */
213static void iowarrior_write_callback(struct urb *urb)
214{
215	struct iowarrior *dev;
216	int status = urb->status;
217
218	dev = urb->context;
219	/* sync/async unlink faults aren't errors */
220	if (status &&
221	    !(status == -ENOENT ||
222	      status == -ECONNRESET || status == -ESHUTDOWN)) {
223		dev_dbg(&dev->interface->dev,
224			"nonzero write bulk status received: %d\n", status);
225	}
226	/* free up our allocated buffer */
227	usb_free_coherent(urb->dev, urb->transfer_buffer_length,
228			  urb->transfer_buffer, urb->transfer_dma);
229	/* tell a waiting writer the interrupt-out-pipe is available again */
230	atomic_dec(&dev->write_busy);
231	wake_up_interruptible(&dev->write_wait);
232}
233
234/**
235 *	iowarrior_delete
236 */
237static inline void iowarrior_delete(struct iowarrior *dev)
238{
239	dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
240	kfree(dev->int_in_buffer);
241	usb_free_urb(dev->int_in_urb);
242	kfree(dev->read_queue);
243	usb_put_intf(dev->interface);
244	kfree(dev);
245}
246
247/*---------------------*/
248/* fops implementation */
249/*---------------------*/
250
251static int read_index(struct iowarrior *dev)
252{
253	int intr_idx, read_idx;
254
255	read_idx = atomic_read(&dev->read_idx);
256	intr_idx = atomic_read(&dev->intr_idx);
257
258	return (read_idx == intr_idx ? -1 : read_idx);
259}
260
261/**
262 *  iowarrior_read
263 */
264static ssize_t iowarrior_read(struct file *file, char __user *buffer,
265			      size_t count, loff_t *ppos)
266{
267	struct iowarrior *dev;
268	int read_idx;
269	int offset;
270
271	dev = file->private_data;
272
273	/* verify that the device wasn't unplugged */
274	if (!dev || !dev->present)
275		return -ENODEV;
276
277	dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
278		dev->minor, count);
279
280	/* read count must be packet size (+ time stamp) */
281	if ((count != dev->report_size)
282	    && (count != (dev->report_size + 1)))
283		return -EINVAL;
284
285	/* repeat until no buffer overrun in callback handler occur */
286	do {
287		atomic_set(&dev->overflow_flag, 0);
288		if ((read_idx = read_index(dev)) == -1) {
289			/* queue empty */
290			if (file->f_flags & O_NONBLOCK)
291				return -EAGAIN;
292			else {
293				//next line will return when there is either new data, or the device is unplugged
294				int r = wait_event_interruptible(dev->read_wait,
295								 (!dev->present
296								  || (read_idx =
297								      read_index
298								      (dev)) !=
299								  -1));
300				if (r) {
301					//we were interrupted by a signal
302					return -ERESTART;
303				}
304				if (!dev->present) {
305					//The device was unplugged
306					return -ENODEV;
307				}
308				if (read_idx == -1) {
309					// Can this happen ???
310					return 0;
311				}
312			}
313		}
314
315		offset = read_idx * (dev->report_size + 1);
316		if (copy_to_user(buffer, dev->read_queue + offset, count)) {
317			return -EFAULT;
318		}
319	} while (atomic_read(&dev->overflow_flag));
320
321	read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
322	atomic_set(&dev->read_idx, read_idx);
323	return count;
324}
325
326/*
327 * iowarrior_write
328 */
329static ssize_t iowarrior_write(struct file *file,
330			       const char __user *user_buffer,
331			       size_t count, loff_t *ppos)
332{
333	struct iowarrior *dev;
334	int retval = 0;
335	char *buf = NULL;	/* for IOW24 and IOW56 we need a buffer */
336	struct urb *int_out_urb = NULL;
337
338	dev = file->private_data;
339
340	mutex_lock(&dev->mutex);
341	/* verify that the device wasn't unplugged */
342	if (!dev->present) {
343		retval = -ENODEV;
344		goto exit;
345	}
346	dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
347		dev->minor, count);
348	/* if count is 0 we're already done */
349	if (count == 0) {
350		retval = 0;
351		goto exit;
352	}
353	/* We only accept full reports */
354	if (count != dev->report_size) {
355		retval = -EINVAL;
356		goto exit;
357	}
358	switch (dev->product_id) {
359	case USB_DEVICE_ID_CODEMERCS_IOW24:
360	case USB_DEVICE_ID_CODEMERCS_IOWPV1:
361	case USB_DEVICE_ID_CODEMERCS_IOWPV2:
362	case USB_DEVICE_ID_CODEMERCS_IOW40:
363		/* IOW24 and IOW40 use a synchronous call */
364		buf = memdup_user(user_buffer, count);
365		if (IS_ERR(buf)) {
366			retval = PTR_ERR(buf);
 
 
 
 
 
367			goto exit;
368		}
369		retval = usb_set_report(dev->interface, 2, 0, buf, count);
370		kfree(buf);
371		goto exit;
372		break;
373	case USB_DEVICE_ID_CODEMERCS_IOW56:
374		/* The IOW56 uses asynchronous IO and more urbs */
375		if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
376			/* Wait until we are below the limit for submitted urbs */
377			if (file->f_flags & O_NONBLOCK) {
378				retval = -EAGAIN;
379				goto exit;
380			} else {
381				retval = wait_event_interruptible(dev->write_wait,
382								  (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
383				if (retval) {
384					/* we were interrupted by a signal */
385					retval = -ERESTART;
386					goto exit;
387				}
388				if (!dev->present) {
389					/* The device was unplugged */
390					retval = -ENODEV;
391					goto exit;
392				}
393				if (!dev->opened) {
394					/* We were closed while waiting for an URB */
395					retval = -ENODEV;
396					goto exit;
397				}
398			}
399		}
400		atomic_inc(&dev->write_busy);
401		int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
402		if (!int_out_urb) {
403			retval = -ENOMEM;
 
404			goto error_no_urb;
405		}
406		buf = usb_alloc_coherent(dev->udev, dev->report_size,
407					 GFP_KERNEL, &int_out_urb->transfer_dma);
408		if (!buf) {
409			retval = -ENOMEM;
410			dev_dbg(&dev->interface->dev,
411				"Unable to allocate buffer\n");
412			goto error_no_buffer;
413		}
414		usb_fill_int_urb(int_out_urb, dev->udev,
415				 usb_sndintpipe(dev->udev,
416						dev->int_out_endpoint->bEndpointAddress),
417				 buf, dev->report_size,
418				 iowarrior_write_callback, dev,
419				 dev->int_out_endpoint->bInterval);
420		int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
421		if (copy_from_user(buf, user_buffer, count)) {
422			retval = -EFAULT;
423			goto error;
424		}
425		usb_anchor_urb(int_out_urb, &dev->submitted);
426		retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
427		if (retval) {
428			dev_dbg(&dev->interface->dev,
429				"submit error %d for urb nr.%d\n",
430				retval, atomic_read(&dev->write_busy));
431			usb_unanchor_urb(int_out_urb);
432			goto error;
433		}
434		/* submit was ok */
435		retval = count;
436		usb_free_urb(int_out_urb);
437		goto exit;
438		break;
439	default:
440		/* what do we have here ? An unsupported Product-ID ? */
441		dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n",
442			__func__, dev->product_id);
443		retval = -EFAULT;
444		goto exit;
445		break;
446	}
447error:
448	usb_free_coherent(dev->udev, dev->report_size, buf,
449			  int_out_urb->transfer_dma);
450error_no_buffer:
451	usb_free_urb(int_out_urb);
452error_no_urb:
453	atomic_dec(&dev->write_busy);
454	wake_up_interruptible(&dev->write_wait);
455exit:
456	mutex_unlock(&dev->mutex);
457	return retval;
458}
459
460/**
461 *	iowarrior_ioctl
462 */
463static long iowarrior_ioctl(struct file *file, unsigned int cmd,
464							unsigned long arg)
465{
466	struct iowarrior *dev = NULL;
467	__u8 *buffer;
468	__u8 __user *user_buffer;
469	int retval;
470	int io_res;		/* checks for bytes read/written and copy_to/from_user results */
471
472	dev = file->private_data;
473	if (!dev)
474		return -ENODEV;
 
475
476	buffer = kzalloc(dev->report_size, GFP_KERNEL);
477	if (!buffer)
478		return -ENOMEM;
479
 
 
480	mutex_lock(&dev->mutex);
481
482	/* verify that the device wasn't unplugged */
483	if (!dev->present) {
484		retval = -ENODEV;
485		goto error_out;
486	}
487
488	dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n",
489		dev->minor, cmd, arg);
490
491	retval = 0;
492	io_res = 0;
493	switch (cmd) {
494	case IOW_WRITE:
495		if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
496		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
497		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
498		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
499			user_buffer = (__u8 __user *)arg;
500			io_res = copy_from_user(buffer, user_buffer,
501						dev->report_size);
502			if (io_res) {
503				retval = -EFAULT;
504			} else {
505				io_res = usb_set_report(dev->interface, 2, 0,
506							buffer,
507							dev->report_size);
508				if (io_res < 0)
509					retval = io_res;
510			}
511		} else {
512			retval = -EINVAL;
513			dev_err(&dev->interface->dev,
514				"ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
515				dev->product_id);
516		}
517		break;
518	case IOW_READ:
519		user_buffer = (__u8 __user *)arg;
520		io_res = usb_get_report(dev->udev,
521					dev->interface->cur_altsetting, 1, 0,
522					buffer, dev->report_size);
523		if (io_res < 0)
524			retval = io_res;
525		else {
526			io_res = copy_to_user(user_buffer, buffer, dev->report_size);
527			if (io_res)
528				retval = -EFAULT;
529		}
530		break;
531	case IOW_GETINFO:
532		{
533			/* Report available information for the device */
534			struct iowarrior_info info;
535			/* needed for power consumption */
536			struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
537
538			memset(&info, 0, sizeof(info));
539			/* directly from the descriptor */
540			info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
541			info.product = dev->product_id;
542			info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
543
544			/* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
545			info.speed = dev->udev->speed;
546			info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
547			info.report_size = dev->report_size;
548
549			/* serial number string has been read earlier 8 chars or empty string */
550			memcpy(info.serial, dev->chip_serial,
551			       sizeof(dev->chip_serial));
552			if (cfg_descriptor == NULL) {
553				info.power = -1;	/* no information available */
554			} else {
555				/* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
556				info.power = cfg_descriptor->bMaxPower * 2;
557			}
558			io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
559					 sizeof(struct iowarrior_info));
560			if (io_res)
561				retval = -EFAULT;
562			break;
563		}
564	default:
565		/* return that we did not understand this ioctl call */
566		retval = -ENOTTY;
567		break;
568	}
569error_out:
570	/* unlock the device */
571	mutex_unlock(&dev->mutex);
 
572	kfree(buffer);
573	return retval;
574}
575
576/**
577 *	iowarrior_open
578 */
579static int iowarrior_open(struct inode *inode, struct file *file)
580{
581	struct iowarrior *dev = NULL;
582	struct usb_interface *interface;
583	int subminor;
584	int retval = 0;
585
 
 
 
586	subminor = iminor(inode);
587
588	interface = usb_find_interface(&iowarrior_driver, subminor);
589	if (!interface) {
590		pr_err("%s - error, can't find device for minor %d\n",
591		       __func__, subminor);
 
592		return -ENODEV;
593	}
594
 
595	dev = usb_get_intfdata(interface);
596	if (!dev)
 
 
597		return -ENODEV;
 
598
599	mutex_lock(&dev->mutex);
 
600
601	/* Only one process can open each device, no sharing. */
602	if (dev->opened) {
603		retval = -EBUSY;
604		goto out;
605	}
606
607	/* setup interrupt handler for receiving values */
608	if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
609		dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
610		retval = -EFAULT;
611		goto out;
612	}
613	/* increment our usage count for the driver */
614	++dev->opened;
615	/* save our object in the file's private structure */
616	file->private_data = dev;
617	retval = 0;
618
619out:
620	mutex_unlock(&dev->mutex);
 
621	return retval;
622}
623
624/**
625 *	iowarrior_release
626 */
627static int iowarrior_release(struct inode *inode, struct file *file)
628{
629	struct iowarrior *dev;
630	int retval = 0;
631
632	dev = file->private_data;
633	if (!dev)
634		return -ENODEV;
 
635
636	dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
637
638	/* lock our device */
639	mutex_lock(&dev->mutex);
640
641	if (dev->opened <= 0) {
642		retval = -ENODEV;	/* close called more than once */
643		mutex_unlock(&dev->mutex);
644	} else {
645		dev->opened = 0;	/* we're closing now */
646		retval = 0;
647		if (dev->present) {
648			/*
649			   The device is still connected so we only shutdown
650			   pending read-/write-ops.
651			 */
652			usb_kill_urb(dev->int_in_urb);
653			wake_up_interruptible(&dev->read_wait);
654			wake_up_interruptible(&dev->write_wait);
655			mutex_unlock(&dev->mutex);
656		} else {
657			/* The device was unplugged, cleanup resources */
658			mutex_unlock(&dev->mutex);
659			iowarrior_delete(dev);
660		}
661	}
662	return retval;
663}
664
665static __poll_t iowarrior_poll(struct file *file, poll_table * wait)
666{
667	struct iowarrior *dev = file->private_data;
668	__poll_t mask = 0;
669
670	if (!dev->present)
671		return EPOLLERR | EPOLLHUP;
672
673	poll_wait(file, &dev->read_wait, wait);
674	poll_wait(file, &dev->write_wait, wait);
675
676	if (!dev->present)
677		return EPOLLERR | EPOLLHUP;
678
679	if (read_index(dev) != -1)
680		mask |= EPOLLIN | EPOLLRDNORM;
681
682	if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
683		mask |= EPOLLOUT | EPOLLWRNORM;
684	return mask;
685}
686
687/*
688 * File operations needed when we register this driver.
689 * This assumes that this driver NEEDS file operations,
690 * of course, which means that the driver is expected
691 * to have a node in the /dev directory. If the USB
692 * device were for a network interface then the driver
693 * would use "struct net_driver" instead, and a serial
694 * device would use "struct tty_driver".
695 */
696static const struct file_operations iowarrior_fops = {
697	.owner = THIS_MODULE,
698	.write = iowarrior_write,
699	.read = iowarrior_read,
700	.unlocked_ioctl = iowarrior_ioctl,
701	.open = iowarrior_open,
702	.release = iowarrior_release,
703	.poll = iowarrior_poll,
704	.llseek = noop_llseek,
705};
706
707static char *iowarrior_devnode(struct device *dev, umode_t *mode)
708{
709	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
710}
711
712/*
713 * usb class driver info in order to get a minor number from the usb core,
714 * and to have the device registered with devfs and the driver core
715 */
716static struct usb_class_driver iowarrior_class = {
717	.name = "iowarrior%d",
718	.devnode = iowarrior_devnode,
719	.fops = &iowarrior_fops,
720	.minor_base = IOWARRIOR_MINOR_BASE,
721};
722
723/*---------------------------------*/
724/*  probe and disconnect functions */
725/*---------------------------------*/
726/**
727 *	iowarrior_probe
728 *
729 *	Called by the usb core when a new device is connected that it thinks
730 *	this driver might be interested in.
731 */
732static int iowarrior_probe(struct usb_interface *interface,
733			   const struct usb_device_id *id)
734{
735	struct usb_device *udev = interface_to_usbdev(interface);
736	struct iowarrior *dev = NULL;
737	struct usb_host_interface *iface_desc;
 
 
738	int retval = -ENOMEM;
739	int res;
740
741	/* allocate memory for our device state and initialize it */
742	dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
743	if (!dev)
 
744		return retval;
 
745
746	mutex_init(&dev->mutex);
747
748	atomic_set(&dev->intr_idx, 0);
749	atomic_set(&dev->read_idx, 0);
 
750	atomic_set(&dev->overflow_flag, 0);
751	init_waitqueue_head(&dev->read_wait);
752	atomic_set(&dev->write_busy, 0);
753	init_waitqueue_head(&dev->write_wait);
754
755	dev->udev = udev;
756	dev->interface = usb_get_intf(interface);
757
758	iface_desc = interface->cur_altsetting;
759	dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
760
761	init_usb_anchor(&dev->submitted);
762
763	res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
764	if (res) {
765		dev_err(&interface->dev, "no interrupt-in endpoint found\n");
766		retval = res;
767		goto error;
768	}
769
770	if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) {
771		res = usb_find_last_int_out_endpoint(iface_desc,
772				&dev->int_out_endpoint);
773		if (res) {
774			dev_err(&interface->dev, "no interrupt-out endpoint found\n");
775			retval = res;
776			goto error;
777		}
778	}
779
780	/* we have to check the report_size often, so remember it in the endianness suitable for our machine */
781	dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
782	if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&
783	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56))
784		/* IOWarrior56 has wMaxPacketSize different from report size */
785		dev->report_size = 7;
786
787	/* create the urb and buffer for reading */
788	dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
789	if (!dev->int_in_urb)
 
790		goto error;
 
791	dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
792	if (!dev->int_in_buffer)
 
793		goto error;
 
794	usb_fill_int_urb(dev->int_in_urb, dev->udev,
795			 usb_rcvintpipe(dev->udev,
796					dev->int_in_endpoint->bEndpointAddress),
797			 dev->int_in_buffer, dev->report_size,
798			 iowarrior_callback, dev,
799			 dev->int_in_endpoint->bInterval);
800	/* create an internal buffer for interrupt data from the device */
801	dev->read_queue =
802	    kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER,
803			  GFP_KERNEL);
804	if (!dev->read_queue)
 
805		goto error;
 
806	/* Get the serial-number of the chip */
807	memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
808	usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
809		   sizeof(dev->chip_serial));
810	if (strlen(dev->chip_serial) != 8)
811		memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
812
813	/* Set the idle timeout to 0, if this is interface 0 */
814	if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
815	    usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
816			    0x0A,
817			    USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
818			    0, NULL, 0, USB_CTRL_SET_TIMEOUT);
819	}
820	/* allow device read and ioctl */
821	dev->present = 1;
822
823	/* we can register the device now, as it is ready */
824	usb_set_intfdata(interface, dev);
825
826	retval = usb_register_dev(interface, &iowarrior_class);
827	if (retval) {
828		/* something prevented us from registering this driver */
829		dev_err(&interface->dev, "Not able to get a minor for this device.\n");
 
830		goto error;
831	}
832
833	dev->minor = interface->minor;
834
835	/* let the user know what node this device is now attached to */
836	dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
837		 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
838		 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
839	return retval;
840
841error:
842	iowarrior_delete(dev);
843	return retval;
844}
845
846/**
847 *	iowarrior_disconnect
848 *
849 *	Called by the usb core when the device is removed from the system.
850 */
851static void iowarrior_disconnect(struct usb_interface *interface)
852{
853	struct iowarrior *dev = usb_get_intfdata(interface);
854	int minor = dev->minor;
855
 
 
 
 
 
 
 
856	usb_deregister_dev(interface, &iowarrior_class);
857
858	mutex_lock(&dev->mutex);
859
860	/* prevent device read, write and ioctl */
861	dev->present = 0;
862
 
 
 
863	if (dev->opened) {
864		/* There is a process that holds a filedescriptor to the device ,
865		   so we only shutdown read-/write-ops going on.
866		   Deleting the device is postponed until close() was called.
867		 */
868		usb_kill_urb(dev->int_in_urb);
869		usb_kill_anchored_urbs(&dev->submitted);
870		wake_up_interruptible(&dev->read_wait);
871		wake_up_interruptible(&dev->write_wait);
872		mutex_unlock(&dev->mutex);
873	} else {
874		/* no process is using the device, cleanup now */
875		mutex_unlock(&dev->mutex);
876		iowarrior_delete(dev);
877	}
878
879	dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
880		 minor - IOWARRIOR_MINOR_BASE);
881}
882
883/* usb specific object needed to register this driver with the usb subsystem */
884static struct usb_driver iowarrior_driver = {
885	.name = "iowarrior",
886	.probe = iowarrior_probe,
887	.disconnect = iowarrior_disconnect,
888	.id_table = iowarrior_ids,
889};
890
891module_usb_driver(iowarrior_driver);