Linux Audio

Check our new training course

Loading...
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  Native support for the I/O-Warrior USB devices
  4 *
  5 *  Copyright (c) 2003-2005, 2020  Code Mercenaries GmbH
  6 *  written by Christian Lucht <lucht@codemercs.com> and
  7 *  Christoph Jung <jung@codemercs.com>
  8 *
  9 *  based on
 10
 11 *  usb-skeleton.c by Greg Kroah-Hartman  <greg@kroah.com>
 12 *  brlvger.c by Stephane Dalton  <sdalton@videotron.ca>
 13 *           and Stephane Doyon   <s.doyon@videotron.ca>
 14 *
 15 *  Released under the GPLv2.
 16 */
 17
 18#include <linux/module.h>
 19#include <linux/usb.h>
 20#include <linux/slab.h>
 21#include <linux/sched.h>
 22#include <linux/mutex.h>
 23#include <linux/poll.h>
 24#include <linux/usb/iowarrior.h>
 25
 26#define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
 27#define DRIVER_DESC "USB IO-Warrior driver"
 28
 29#define USB_VENDOR_ID_CODEMERCS		1984
 30/* low speed iowarrior */
 31#define USB_DEVICE_ID_CODEMERCS_IOW40	0x1500
 32#define USB_DEVICE_ID_CODEMERCS_IOW24	0x1501
 33#define USB_DEVICE_ID_CODEMERCS_IOWPV1	0x1511
 34#define USB_DEVICE_ID_CODEMERCS_IOWPV2	0x1512
 35/* full speed iowarrior */
 36#define USB_DEVICE_ID_CODEMERCS_IOW56	0x1503
 37/* fuller speed iowarrior */
 38#define USB_DEVICE_ID_CODEMERCS_IOW28	0x1504
 39#define USB_DEVICE_ID_CODEMERCS_IOW28L	0x1505
 40#define USB_DEVICE_ID_CODEMERCS_IOW100	0x1506
 41
 42/* OEMed devices */
 43#define USB_DEVICE_ID_CODEMERCS_IOW24SAG	0x158a
 44#define USB_DEVICE_ID_CODEMERCS_IOW56AM		0x158b
 45
 46/* Get a minor range for your devices from the usb maintainer */
 47#ifdef CONFIG_USB_DYNAMIC_MINORS
 48#define IOWARRIOR_MINOR_BASE	0
 49#else
 50#define IOWARRIOR_MINOR_BASE	208	// SKELETON_MINOR_BASE 192 + 16, not official yet
 51#endif
 52
 53/* interrupt input queue size */
 54#define MAX_INTERRUPT_BUFFER 16
 55/*
 56   maximum number of urbs that are submitted for writes at the same time,
 57   this applies to the IOWarrior56 only!
 58   IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
 59*/
 60#define MAX_WRITES_IN_FLIGHT 4
 61
 62MODULE_AUTHOR(DRIVER_AUTHOR);
 63MODULE_DESCRIPTION(DRIVER_DESC);
 64MODULE_LICENSE("GPL");
 65
 66static struct usb_driver iowarrior_driver;
 67
 68/*--------------*/
 69/*     data     */
 70/*--------------*/
 71
 72/* Structure to hold all of our device specific stuff */
 73struct iowarrior {
 74	struct mutex mutex;			/* locks this structure */
 75	struct usb_device *udev;		/* save off the usb device pointer */
 76	struct usb_interface *interface;	/* the interface for this device */
 77	unsigned char minor;			/* the starting minor number for this device */
 78	struct usb_endpoint_descriptor *int_out_endpoint;	/* endpoint for reading (needed for IOW56 only) */
 79	struct usb_endpoint_descriptor *int_in_endpoint;	/* endpoint for reading */
 80	struct urb *int_in_urb;		/* the urb for reading data */
 81	unsigned char *int_in_buffer;	/* buffer for data to be read */
 82	unsigned char serial_number;	/* to detect lost packages */
 83	unsigned char *read_queue;	/* size is MAX_INTERRUPT_BUFFER * packet size */
 84	wait_queue_head_t read_wait;
 85	wait_queue_head_t write_wait;	/* wait-queue for writing to the device */
 86	atomic_t write_busy;		/* number of write-urbs submitted */
 87	atomic_t read_idx;
 88	atomic_t intr_idx;
 89	atomic_t overflow_flag;		/* signals an index 'rollover' */
 90	int present;			/* this is 1 as long as the device is connected */
 91	int opened;			/* this is 1 if the device is currently open */
 92	char chip_serial[9];		/* the serial number string of the chip connected */
 93	int report_size;		/* number of bytes in a report */
 94	u16 product_id;
 95	struct usb_anchor submitted;
 96};
 97
 98/*--------------*/
 99/*    globals   */
100/*--------------*/
101
102/*
103 *  USB spec identifies 5 second timeouts.
104 */
105#define GET_TIMEOUT 5
106#define USB_REQ_GET_REPORT  0x01
107//#if 0
108static int usb_get_report(struct usb_device *dev,
109			  struct usb_host_interface *inter, unsigned char type,
110			  unsigned char id, void *buf, int size)
111{
112	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
113			       USB_REQ_GET_REPORT,
114			       USB_DIR_IN | USB_TYPE_CLASS |
115			       USB_RECIP_INTERFACE, (type << 8) + id,
116			       inter->desc.bInterfaceNumber, buf, size,
117			       GET_TIMEOUT*HZ);
118}
119//#endif
120
121#define USB_REQ_SET_REPORT 0x09
122
123static int usb_set_report(struct usb_interface *intf, unsigned char type,
124			  unsigned char id, void *buf, int size)
125{
126	return usb_control_msg(interface_to_usbdev(intf),
127			       usb_sndctrlpipe(interface_to_usbdev(intf), 0),
128			       USB_REQ_SET_REPORT,
129			       USB_TYPE_CLASS | USB_RECIP_INTERFACE,
130			       (type << 8) + id,
131			       intf->cur_altsetting->desc.bInterfaceNumber, buf,
132			       size, HZ);
133}
134
135/*---------------------*/
136/* driver registration */
137/*---------------------*/
138/* table of devices that work with this driver */
139static const struct usb_device_id iowarrior_ids[] = {
140	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
141	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
142	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
143	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
144	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
145	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)},
146	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)},
147	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)},
148	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)},
149	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)},
150	{}			/* Terminating entry */
151};
152MODULE_DEVICE_TABLE(usb, iowarrior_ids);
153
154/*
155 * USB callback handler for reading data
156 */
157static void iowarrior_callback(struct urb *urb)
158{
159	struct iowarrior *dev = urb->context;
160	int intr_idx;
161	int read_idx;
162	int aux_idx;
163	int offset;
164	int status = urb->status;
165	int retval;
166
167	switch (status) {
168	case 0:
169		/* success */
170		break;
171	case -ECONNRESET:
172	case -ENOENT:
173	case -ESHUTDOWN:
174		return;
175	default:
176		goto exit;
177	}
178
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			goto exit;
194		}
195	}
196
197	/* aux_idx become next intr_idx */
198	aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
199	if (read_idx == aux_idx) {
200		/* queue full, dropping oldest input */
201		read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
202		atomic_set(&dev->read_idx, read_idx);
203		atomic_set(&dev->overflow_flag, 1);
204	}
205
206	/* +1 for serial number */
207	offset = intr_idx * (dev->report_size + 1);
208	memcpy(dev->read_queue + offset, urb->transfer_buffer,
209	       dev->report_size);
210	*(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
211
212	atomic_set(&dev->intr_idx, aux_idx);
213	/* tell the blocking read about the new data */
214	wake_up_interruptible(&dev->read_wait);
215
216exit:
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\n",
220			__func__, retval);
221
222}
223
224/*
225 * USB Callback handler for write-ops
226 */
227static void iowarrior_write_callback(struct urb *urb)
228{
229	struct iowarrior *dev;
230	int status = urb->status;
231
232	dev = urb->context;
233	/* sync/async unlink faults aren't errors */
234	if (status &&
235	    !(status == -ENOENT ||
236	      status == -ECONNRESET || status == -ESHUTDOWN)) {
237		dev_dbg(&dev->interface->dev,
238			"nonzero write bulk status received: %d\n", status);
239	}
240	/* free up our allocated buffer */
241	usb_free_coherent(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 */
251static inline void iowarrior_delete(struct iowarrior *dev)
252{
253	dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
254	kfree(dev->int_in_buffer);
255	usb_free_urb(dev->int_in_urb);
256	kfree(dev->read_queue);
257	usb_put_intf(dev->interface);
258	kfree(dev);
259}
260
261/*---------------------*/
262/* fops implementation */
263/*---------------------*/
264
265static int read_index(struct iowarrior *dev)
266{
267	int intr_idx, read_idx;
268
269	read_idx = atomic_read(&dev->read_idx);
270	intr_idx = atomic_read(&dev->intr_idx);
271
272	return (read_idx == intr_idx ? -1 : read_idx);
273}
274
275/*
276 *  iowarrior_read
277 */
278static ssize_t iowarrior_read(struct file *file, char __user *buffer,
279			      size_t count, loff_t *ppos)
280{
281	struct iowarrior *dev;
282	int read_idx;
283	int offset;
284
285	dev = file->private_data;
286
287	/* verify that the device wasn't unplugged */
288	if (!dev || !dev->present)
289		return -ENODEV;
290
291	dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
292		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 empty */
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	dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
361		dev->minor, count);
362	/* if count is 0 we're already done */
363	if (count == 0) {
364		retval = 0;
365		goto exit;
366	}
367	/* We only accept full reports */
368	if (count != dev->report_size) {
369		retval = -EINVAL;
370		goto exit;
371	}
372	switch (dev->product_id) {
373	case USB_DEVICE_ID_CODEMERCS_IOW24:
374	case USB_DEVICE_ID_CODEMERCS_IOW24SAG:
375	case USB_DEVICE_ID_CODEMERCS_IOWPV1:
376	case USB_DEVICE_ID_CODEMERCS_IOWPV2:
377	case USB_DEVICE_ID_CODEMERCS_IOW40:
378		/* IOW24 and IOW40 use a synchronous call */
379		buf = memdup_user(user_buffer, count);
380		if (IS_ERR(buf)) {
381			retval = PTR_ERR(buf);
382			goto exit;
383		}
384		retval = usb_set_report(dev->interface, 2, 0, buf, count);
385		kfree(buf);
386		goto exit;
387		break;
388	case USB_DEVICE_ID_CODEMERCS_IOW56:
389	case USB_DEVICE_ID_CODEMERCS_IOW56AM:
390	case USB_DEVICE_ID_CODEMERCS_IOW28:
391	case USB_DEVICE_ID_CODEMERCS_IOW28L:
392	case USB_DEVICE_ID_CODEMERCS_IOW100:
393		/* The IOW56 uses asynchronous IO and more urbs */
394		if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
395			/* Wait until we are below the limit for submitted urbs */
396			if (file->f_flags & O_NONBLOCK) {
397				retval = -EAGAIN;
398				goto exit;
399			} else {
400				retval = wait_event_interruptible(dev->write_wait,
401								  (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
402				if (retval) {
403					/* we were interrupted by a signal */
404					retval = -ERESTART;
405					goto exit;
406				}
407				if (!dev->present) {
408					/* The device was unplugged */
409					retval = -ENODEV;
410					goto exit;
411				}
412				if (!dev->opened) {
413					/* We were closed while waiting for an URB */
414					retval = -ENODEV;
415					goto exit;
416				}
417			}
418		}
419		atomic_inc(&dev->write_busy);
420		int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
421		if (!int_out_urb) {
422			retval = -ENOMEM;
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			dev_dbg(&dev->interface->dev,
430				"Unable to allocate buffer\n");
431			goto error_no_buffer;
432		}
433		usb_fill_int_urb(int_out_urb, dev->udev,
434				 usb_sndintpipe(dev->udev,
435						dev->int_out_endpoint->bEndpointAddress),
436				 buf, dev->report_size,
437				 iowarrior_write_callback, dev,
438				 dev->int_out_endpoint->bInterval);
439		int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
440		if (copy_from_user(buf, user_buffer, count)) {
441			retval = -EFAULT;
442			goto error;
443		}
444		usb_anchor_urb(int_out_urb, &dev->submitted);
445		retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
446		if (retval) {
447			dev_dbg(&dev->interface->dev,
448				"submit error %d for urb nr.%d\n",
449				retval, atomic_read(&dev->write_busy));
450			usb_unanchor_urb(int_out_urb);
451			goto error;
452		}
453		/* submit was ok */
454		retval = count;
455		usb_free_urb(int_out_urb);
456		goto exit;
457		break;
458	default:
459		/* what do we have here ? An unsupported Product-ID ? */
460		dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n",
461			__func__, dev->product_id);
462		retval = -EFAULT;
463		goto exit;
464		break;
465	}
466error:
467	usb_free_coherent(dev->udev, dev->report_size, buf,
468			  int_out_urb->transfer_dma);
469error_no_buffer:
470	usb_free_urb(int_out_urb);
471error_no_urb:
472	atomic_dec(&dev->write_busy);
473	wake_up_interruptible(&dev->write_wait);
474exit:
475	mutex_unlock(&dev->mutex);
476	return retval;
477}
478
479/*
480 *	iowarrior_ioctl
481 */
482static long iowarrior_ioctl(struct file *file, unsigned int cmd,
483							unsigned long arg)
484{
485	struct iowarrior *dev = NULL;
486	__u8 *buffer;
487	__u8 __user *user_buffer;
488	int retval;
489	int io_res;		/* checks for bytes read/written and copy_to/from_user results */
490
491	dev = file->private_data;
492	if (!dev)
493		return -ENODEV;
494
495	buffer = kzalloc(dev->report_size, GFP_KERNEL);
496	if (!buffer)
497		return -ENOMEM;
498
499	mutex_lock(&dev->mutex);
500
501	/* verify that the device wasn't unplugged */
502	if (!dev->present) {
503		retval = -ENODEV;
504		goto error_out;
505	}
506
507	dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n",
508		dev->minor, cmd, arg);
509
510	retval = 0;
511	io_res = 0;
512	switch (cmd) {
513	case IOW_WRITE:
514		if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
515		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG ||
516		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
517		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
518		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
519			user_buffer = (__u8 __user *)arg;
520			io_res = copy_from_user(buffer, user_buffer,
521						dev->report_size);
522			if (io_res) {
523				retval = -EFAULT;
524			} else {
525				io_res = usb_set_report(dev->interface, 2, 0,
526							buffer,
527							dev->report_size);
528				if (io_res < 0)
529					retval = io_res;
530			}
531		} else {
532			retval = -EINVAL;
533			dev_err(&dev->interface->dev,
534				"ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
535				dev->product_id);
536		}
537		break;
538	case IOW_READ:
539		user_buffer = (__u8 __user *)arg;
540		io_res = usb_get_report(dev->udev,
541					dev->interface->cur_altsetting, 1, 0,
542					buffer, dev->report_size);
543		if (io_res < 0)
544			retval = io_res;
545		else {
546			io_res = copy_to_user(user_buffer, buffer, dev->report_size);
547			if (io_res)
548				retval = -EFAULT;
549		}
550		break;
551	case IOW_GETINFO:
552		{
553			/* Report available information for the device */
554			struct iowarrior_info info;
555			/* needed for power consumption */
556			struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
557
558			memset(&info, 0, sizeof(info));
559			/* directly from the descriptor */
560			info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
561			info.product = dev->product_id;
562			info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
563
564			/* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
565			info.speed = dev->udev->speed;
566			info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
567			info.report_size = dev->report_size;
568
569			/* serial number string has been read earlier 8 chars or empty string */
570			memcpy(info.serial, dev->chip_serial,
571			       sizeof(dev->chip_serial));
572			if (cfg_descriptor == NULL) {
573				info.power = -1;	/* no information available */
574			} else {
575				/* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
576				info.power = cfg_descriptor->bMaxPower * 2;
577			}
578			io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
579					 sizeof(struct iowarrior_info));
580			if (io_res)
581				retval = -EFAULT;
582			break;
583		}
584	default:
585		/* return that we did not understand this ioctl call */
586		retval = -ENOTTY;
587		break;
588	}
589error_out:
590	/* unlock the device */
591	mutex_unlock(&dev->mutex);
592	kfree(buffer);
593	return retval;
594}
595
596/*
597 *	iowarrior_open
598 */
599static int iowarrior_open(struct inode *inode, struct file *file)
600{
601	struct iowarrior *dev = NULL;
602	struct usb_interface *interface;
603	int subminor;
604	int retval = 0;
605
606	subminor = iminor(inode);
607
608	interface = usb_find_interface(&iowarrior_driver, subminor);
609	if (!interface) {
610		pr_err("%s - error, can't find device for minor %d\n",
611		       __func__, subminor);
612		return -ENODEV;
613	}
614
615	dev = usb_get_intfdata(interface);
616	if (!dev)
617		return -ENODEV;
618
619	mutex_lock(&dev->mutex);
620
621	/* Only one process can open each device, no sharing. */
622	if (dev->opened) {
623		retval = -EBUSY;
624		goto out;
625	}
626
627	/* setup interrupt handler for receiving values */
628	if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
629		dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
630		retval = -EFAULT;
631		goto out;
632	}
633	/* increment our usage count for the driver */
634	++dev->opened;
635	/* save our object in the file's private structure */
636	file->private_data = dev;
637	retval = 0;
638
639out:
640	mutex_unlock(&dev->mutex);
641	return retval;
642}
643
644/*
645 *	iowarrior_release
646 */
647static int iowarrior_release(struct inode *inode, struct file *file)
648{
649	struct iowarrior *dev;
650	int retval = 0;
651
652	dev = file->private_data;
653	if (!dev)
654		return -ENODEV;
655
656	dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
657
658	/* lock our device */
659	mutex_lock(&dev->mutex);
660
661	if (dev->opened <= 0) {
662		retval = -ENODEV;	/* close called more than once */
663		mutex_unlock(&dev->mutex);
664	} else {
665		dev->opened = 0;	/* we're closing now */
666		retval = 0;
667		if (dev->present) {
668			/*
669			   The device is still connected so we only shutdown
670			   pending read-/write-ops.
671			 */
672			usb_kill_urb(dev->int_in_urb);
673			wake_up_interruptible(&dev->read_wait);
674			wake_up_interruptible(&dev->write_wait);
675			mutex_unlock(&dev->mutex);
676		} else {
677			/* The device was unplugged, cleanup resources */
678			mutex_unlock(&dev->mutex);
679			iowarrior_delete(dev);
680		}
681	}
682	return retval;
683}
684
685static __poll_t iowarrior_poll(struct file *file, poll_table * wait)
686{
687	struct iowarrior *dev = file->private_data;
688	__poll_t mask = 0;
689
690	if (!dev->present)
691		return EPOLLERR | EPOLLHUP;
692
693	poll_wait(file, &dev->read_wait, wait);
694	poll_wait(file, &dev->write_wait, wait);
695
696	if (!dev->present)
697		return EPOLLERR | EPOLLHUP;
698
699	if (read_index(dev) != -1)
700		mask |= EPOLLIN | EPOLLRDNORM;
701
702	if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
703		mask |= EPOLLOUT | EPOLLWRNORM;
704	return mask;
705}
706
707/*
708 * File operations needed when we register this driver.
709 * This assumes that this driver NEEDS file operations,
710 * of course, which means that the driver is expected
711 * to have a node in the /dev directory. If the USB
712 * device were for a network interface then the driver
713 * would use "struct net_driver" instead, and a serial
714 * device would use "struct tty_driver".
715 */
716static const struct file_operations iowarrior_fops = {
717	.owner = THIS_MODULE,
718	.write = iowarrior_write,
719	.read = iowarrior_read,
720	.unlocked_ioctl = iowarrior_ioctl,
721	.open = iowarrior_open,
722	.release = iowarrior_release,
723	.poll = iowarrior_poll,
724	.llseek = noop_llseek,
725};
726
727static char *iowarrior_devnode(struct device *dev, umode_t *mode)
728{
729	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
730}
731
732/*
733 * usb class driver info in order to get a minor number from the usb core,
734 * and to have the device registered with devfs and the driver core
735 */
736static struct usb_class_driver iowarrior_class = {
737	.name = "iowarrior%d",
738	.devnode = iowarrior_devnode,
739	.fops = &iowarrior_fops,
740	.minor_base = IOWARRIOR_MINOR_BASE,
741};
742
743/*---------------------------------*/
744/*  probe and disconnect functions */
745/*---------------------------------*/
746/*
747 *	iowarrior_probe
748 *
749 *	Called by the usb core when a new device is connected that it thinks
750 *	this driver might be interested in.
751 */
752static int iowarrior_probe(struct usb_interface *interface,
753			   const struct usb_device_id *id)
754{
755	struct usb_device *udev = interface_to_usbdev(interface);
756	struct iowarrior *dev = NULL;
757	struct usb_host_interface *iface_desc;
758	int retval = -ENOMEM;
759	int res;
760
761	/* allocate memory for our device state and initialize it */
762	dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
763	if (!dev)
764		return retval;
765
766	mutex_init(&dev->mutex);
767
768	atomic_set(&dev->intr_idx, 0);
769	atomic_set(&dev->read_idx, 0);
770	atomic_set(&dev->overflow_flag, 0);
771	init_waitqueue_head(&dev->read_wait);
772	atomic_set(&dev->write_busy, 0);
773	init_waitqueue_head(&dev->write_wait);
774
775	dev->udev = udev;
776	dev->interface = usb_get_intf(interface);
777
778	iface_desc = interface->cur_altsetting;
779	dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
780
781	init_usb_anchor(&dev->submitted);
782
783	res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
784	if (res) {
785		dev_err(&interface->dev, "no interrupt-in endpoint found\n");
786		retval = res;
787		goto error;
788	}
789
790	if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) ||
791	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) ||
792	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) ||
793	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) ||
794	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) {
795		res = usb_find_last_int_out_endpoint(iface_desc,
796				&dev->int_out_endpoint);
797		if (res) {
798			dev_err(&interface->dev, "no interrupt-out endpoint found\n");
799			retval = res;
800			goto error;
801		}
802	}
803
804	/* we have to check the report_size often, so remember it in the endianness suitable for our machine */
805	dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
806
807	/*
808	 * Some devices need the report size to be different than the
809	 * endpoint size.
810	 */
811	if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
812		switch (dev->product_id) {
813		case USB_DEVICE_ID_CODEMERCS_IOW56:
814		case USB_DEVICE_ID_CODEMERCS_IOW56AM:
815			dev->report_size = 7;
816			break;
817
818		case USB_DEVICE_ID_CODEMERCS_IOW28:
819		case USB_DEVICE_ID_CODEMERCS_IOW28L:
820			dev->report_size = 4;
821			break;
822
823		case USB_DEVICE_ID_CODEMERCS_IOW100:
824			dev->report_size = 13;
825			break;
826		}
827	}
828
829	/* create the urb and buffer for reading */
830	dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
831	if (!dev->int_in_urb)
832		goto error;
833	dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
834	if (!dev->int_in_buffer)
835		goto error;
836	usb_fill_int_urb(dev->int_in_urb, dev->udev,
837			 usb_rcvintpipe(dev->udev,
838					dev->int_in_endpoint->bEndpointAddress),
839			 dev->int_in_buffer, dev->report_size,
840			 iowarrior_callback, dev,
841			 dev->int_in_endpoint->bInterval);
842	/* create an internal buffer for interrupt data from the device */
843	dev->read_queue =
844	    kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER,
845			  GFP_KERNEL);
846	if (!dev->read_queue)
847		goto error;
848	/* Get the serial-number of the chip */
849	memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
850	usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
851		   sizeof(dev->chip_serial));
852	if (strlen(dev->chip_serial) != 8)
853		memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
854
855	/* Set the idle timeout to 0, if this is interface 0 */
856	if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
857	    usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
858			    0x0A,
859			    USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
860			    0, NULL, 0, USB_CTRL_SET_TIMEOUT);
861	}
862	/* allow device read and ioctl */
863	dev->present = 1;
864
865	/* we can register the device now, as it is ready */
866	usb_set_intfdata(interface, dev);
867
868	retval = usb_register_dev(interface, &iowarrior_class);
869	if (retval) {
870		/* something prevented us from registering this driver */
871		dev_err(&interface->dev, "Not able to get a minor for this device.\n");
872		goto error;
873	}
874
875	dev->minor = interface->minor;
876
877	/* let the user know what node this device is now attached to */
878	dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
879		 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
880		 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
881	return retval;
882
883error:
884	iowarrior_delete(dev);
885	return retval;
886}
887
888/*
889 *	iowarrior_disconnect
890 *
891 *	Called by the usb core when the device is removed from the system.
892 */
893static void iowarrior_disconnect(struct usb_interface *interface)
894{
895	struct iowarrior *dev = usb_get_intfdata(interface);
896	int minor = dev->minor;
897
898	usb_deregister_dev(interface, &iowarrior_class);
899
900	mutex_lock(&dev->mutex);
901
902	/* prevent device read, write and ioctl */
903	dev->present = 0;
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		usb_kill_anchored_urbs(&dev->submitted);
912		wake_up_interruptible(&dev->read_wait);
913		wake_up_interruptible(&dev->write_wait);
914		mutex_unlock(&dev->mutex);
915	} else {
916		/* no process is using the device, cleanup now */
917		mutex_unlock(&dev->mutex);
918		iowarrior_delete(dev);
919	}
920
921	dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
922		 minor - IOWARRIOR_MINOR_BASE);
923}
924
925/* usb specific object needed to register this driver with the usb subsystem */
926static struct usb_driver iowarrior_driver = {
927	.name = "iowarrior",
928	.probe = iowarrior_probe,
929	.disconnect = iowarrior_disconnect,
930	.id_table = iowarrior_ids,
931};
932
933module_usb_driver(iowarrior_driver);
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  Native support for the I/O-Warrior USB devices
  4 *
  5 *  Copyright (c) 2003-2005, 2020  Code Mercenaries GmbH
  6 *  written by Christian Lucht <lucht@codemercs.com> and
  7 *  Christoph Jung <jung@codemercs.com>
  8 *
  9 *  based on
 10
 11 *  usb-skeleton.c by Greg Kroah-Hartman  <greg@kroah.com>
 12 *  brlvger.c by Stephane Dalton  <sdalton@videotron.ca>
 13 *           and Stephane Doyon   <s.doyon@videotron.ca>
 14 *
 15 *  Released under the GPLv2.
 16 */
 17
 18#include <linux/module.h>
 19#include <linux/usb.h>
 20#include <linux/slab.h>
 21#include <linux/sched.h>
 22#include <linux/mutex.h>
 23#include <linux/poll.h>
 24#include <linux/usb/iowarrior.h>
 25
 26#define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
 27#define DRIVER_DESC "USB IO-Warrior driver"
 28
 29#define USB_VENDOR_ID_CODEMERCS		1984
 30/* low speed iowarrior */
 31#define USB_DEVICE_ID_CODEMERCS_IOW40	0x1500
 32#define USB_DEVICE_ID_CODEMERCS_IOW24	0x1501
 33#define USB_DEVICE_ID_CODEMERCS_IOWPV1	0x1511
 34#define USB_DEVICE_ID_CODEMERCS_IOWPV2	0x1512
 35/* full speed iowarrior */
 36#define USB_DEVICE_ID_CODEMERCS_IOW56	0x1503
 37/* fuller speed iowarrior */
 38#define USB_DEVICE_ID_CODEMERCS_IOW28	0x1504
 39#define USB_DEVICE_ID_CODEMERCS_IOW28L	0x1505
 40#define USB_DEVICE_ID_CODEMERCS_IOW100	0x1506
 41
 42/* OEMed devices */
 43#define USB_DEVICE_ID_CODEMERCS_IOW24SAG	0x158a
 44#define USB_DEVICE_ID_CODEMERCS_IOW56AM		0x158b
 45
 46/* Get a minor range for your devices from the usb maintainer */
 47#ifdef CONFIG_USB_DYNAMIC_MINORS
 48#define IOWARRIOR_MINOR_BASE	0
 49#else
 50#define IOWARRIOR_MINOR_BASE	208	// SKELETON_MINOR_BASE 192 + 16, not official yet
 51#endif
 52
 53/* interrupt input queue size */
 54#define MAX_INTERRUPT_BUFFER 16
 55/*
 56   maximum number of urbs that are submitted for writes at the same time,
 57   this applies to the IOWarrior56 only!
 58   IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
 59*/
 60#define MAX_WRITES_IN_FLIGHT 4
 61
 62MODULE_AUTHOR(DRIVER_AUTHOR);
 63MODULE_DESCRIPTION(DRIVER_DESC);
 64MODULE_LICENSE("GPL");
 65
 66static struct usb_driver iowarrior_driver;
 67
 68/*--------------*/
 69/*     data     */
 70/*--------------*/
 71
 72/* Structure to hold all of our device specific stuff */
 73struct iowarrior {
 74	struct mutex mutex;			/* locks this structure */
 75	struct usb_device *udev;		/* save off the usb device pointer */
 76	struct usb_interface *interface;	/* the interface for this device */
 77	unsigned char minor;			/* the starting minor number for this device */
 78	struct usb_endpoint_descriptor *int_out_endpoint;	/* endpoint for reading (needed for IOW56 only) */
 79	struct usb_endpoint_descriptor *int_in_endpoint;	/* endpoint for reading */
 80	struct urb *int_in_urb;		/* the urb for reading data */
 81	unsigned char *int_in_buffer;	/* buffer for data to be read */
 82	unsigned char serial_number;	/* to detect lost packages */
 83	unsigned char *read_queue;	/* size is MAX_INTERRUPT_BUFFER * packet size */
 84	wait_queue_head_t read_wait;
 85	wait_queue_head_t write_wait;	/* wait-queue for writing to the device */
 86	atomic_t write_busy;		/* number of write-urbs submitted */
 87	atomic_t read_idx;
 88	atomic_t intr_idx;
 89	atomic_t overflow_flag;		/* signals an index 'rollover' */
 90	int present;			/* this is 1 as long as the device is connected */
 91	int opened;			/* this is 1 if the device is currently open */
 92	char chip_serial[9];		/* the serial number string of the chip connected */
 93	int report_size;		/* number of bytes in a report */
 94	u16 product_id;
 95	struct usb_anchor submitted;
 96};
 97
 98/*--------------*/
 99/*    globals   */
100/*--------------*/
101
 
 
 
 
102#define USB_REQ_GET_REPORT  0x01
103//#if 0
104static int usb_get_report(struct usb_device *dev,
105			  struct usb_host_interface *inter, unsigned char type,
106			  unsigned char id, void *buf, int size)
107{
108	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
109			       USB_REQ_GET_REPORT,
110			       USB_DIR_IN | USB_TYPE_CLASS |
111			       USB_RECIP_INTERFACE, (type << 8) + id,
112			       inter->desc.bInterfaceNumber, buf, size,
113			       USB_CTRL_GET_TIMEOUT);
114}
115//#endif
116
117#define USB_REQ_SET_REPORT 0x09
118
119static int usb_set_report(struct usb_interface *intf, unsigned char type,
120			  unsigned char id, void *buf, int size)
121{
122	return usb_control_msg(interface_to_usbdev(intf),
123			       usb_sndctrlpipe(interface_to_usbdev(intf), 0),
124			       USB_REQ_SET_REPORT,
125			       USB_TYPE_CLASS | USB_RECIP_INTERFACE,
126			       (type << 8) + id,
127			       intf->cur_altsetting->desc.bInterfaceNumber, buf,
128			       size, 1000);
129}
130
131/*---------------------*/
132/* driver registration */
133/*---------------------*/
134/* table of devices that work with this driver */
135static const struct usb_device_id iowarrior_ids[] = {
136	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
137	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
138	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
139	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
140	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
141	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)},
142	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)},
143	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)},
144	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)},
145	{USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)},
146	{}			/* Terminating entry */
147};
148MODULE_DEVICE_TABLE(usb, iowarrior_ids);
149
150/*
151 * USB callback handler for reading data
152 */
153static void iowarrior_callback(struct urb *urb)
154{
155	struct iowarrior *dev = urb->context;
156	int intr_idx;
157	int read_idx;
158	int aux_idx;
159	int offset;
160	int status = urb->status;
161	int retval;
162
163	switch (status) {
164	case 0:
165		/* success */
166		break;
167	case -ECONNRESET:
168	case -ENOENT:
169	case -ESHUTDOWN:
170		return;
171	default:
172		goto exit;
173	}
174
175	intr_idx = atomic_read(&dev->intr_idx);
176	/* aux_idx become previous intr_idx */
177	aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
178	read_idx = atomic_read(&dev->read_idx);
179
180	/* queue is not empty and it's interface 0 */
181	if ((intr_idx != read_idx)
182	    && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
183		/* + 1 for serial number */
184		offset = aux_idx * (dev->report_size + 1);
185		if (!memcmp
186		    (dev->read_queue + offset, urb->transfer_buffer,
187		     dev->report_size)) {
188			/* equal values on interface 0 will be ignored */
189			goto exit;
190		}
191	}
192
193	/* aux_idx become next intr_idx */
194	aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
195	if (read_idx == aux_idx) {
196		/* queue full, dropping oldest input */
197		read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
198		atomic_set(&dev->read_idx, read_idx);
199		atomic_set(&dev->overflow_flag, 1);
200	}
201
202	/* +1 for serial number */
203	offset = intr_idx * (dev->report_size + 1);
204	memcpy(dev->read_queue + offset, urb->transfer_buffer,
205	       dev->report_size);
206	*(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
207
208	atomic_set(&dev->intr_idx, aux_idx);
209	/* tell the blocking read about the new data */
210	wake_up_interruptible(&dev->read_wait);
211
212exit:
213	retval = usb_submit_urb(urb, GFP_ATOMIC);
214	if (retval)
215		dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n",
216			__func__, retval);
217
218}
219
220/*
221 * USB Callback handler for write-ops
222 */
223static void iowarrior_write_callback(struct urb *urb)
224{
225	struct iowarrior *dev;
226	int status = urb->status;
227
228	dev = urb->context;
229	/* sync/async unlink faults aren't errors */
230	if (status &&
231	    !(status == -ENOENT ||
232	      status == -ECONNRESET || status == -ESHUTDOWN)) {
233		dev_dbg(&dev->interface->dev,
234			"nonzero write bulk status received: %d\n", status);
235	}
236	/* free up our allocated buffer */
237	usb_free_coherent(urb->dev, urb->transfer_buffer_length,
238			  urb->transfer_buffer, urb->transfer_dma);
239	/* tell a waiting writer the interrupt-out-pipe is available again */
240	atomic_dec(&dev->write_busy);
241	wake_up_interruptible(&dev->write_wait);
242}
243
244/*
245 *	iowarrior_delete
246 */
247static inline void iowarrior_delete(struct iowarrior *dev)
248{
249	dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
250	kfree(dev->int_in_buffer);
251	usb_free_urb(dev->int_in_urb);
252	kfree(dev->read_queue);
253	usb_put_intf(dev->interface);
254	kfree(dev);
255}
256
257/*---------------------*/
258/* fops implementation */
259/*---------------------*/
260
261static int read_index(struct iowarrior *dev)
262{
263	int intr_idx, read_idx;
264
265	read_idx = atomic_read(&dev->read_idx);
266	intr_idx = atomic_read(&dev->intr_idx);
267
268	return (read_idx == intr_idx ? -1 : read_idx);
269}
270
271/*
272 *  iowarrior_read
273 */
274static ssize_t iowarrior_read(struct file *file, char __user *buffer,
275			      size_t count, loff_t *ppos)
276{
277	struct iowarrior *dev;
278	int read_idx;
279	int offset;
280
281	dev = file->private_data;
282
283	/* verify that the device wasn't unplugged */
284	if (!dev || !dev->present)
285		return -ENODEV;
286
287	dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
288		dev->minor, count);
289
290	/* read count must be packet size (+ time stamp) */
291	if ((count != dev->report_size)
292	    && (count != (dev->report_size + 1)))
293		return -EINVAL;
294
295	/* repeat until no buffer overrun in callback handler occur */
296	do {
297		atomic_set(&dev->overflow_flag, 0);
298		if ((read_idx = read_index(dev)) == -1) {
299			/* queue empty */
300			if (file->f_flags & O_NONBLOCK)
301				return -EAGAIN;
302			else {
303				//next line will return when there is either new data, or the device is unplugged
304				int r = wait_event_interruptible(dev->read_wait,
305								 (!dev->present
306								  || (read_idx =
307								      read_index
308								      (dev)) !=
309								  -1));
310				if (r) {
311					//we were interrupted by a signal
312					return -ERESTART;
313				}
314				if (!dev->present) {
315					//The device was unplugged
316					return -ENODEV;
317				}
318				if (read_idx == -1) {
319					// Can this happen ???
320					return 0;
321				}
322			}
323		}
324
325		offset = read_idx * (dev->report_size + 1);
326		if (copy_to_user(buffer, dev->read_queue + offset, count)) {
327			return -EFAULT;
328		}
329	} while (atomic_read(&dev->overflow_flag));
330
331	read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
332	atomic_set(&dev->read_idx, read_idx);
333	return count;
334}
335
336/*
337 * iowarrior_write
338 */
339static ssize_t iowarrior_write(struct file *file,
340			       const char __user *user_buffer,
341			       size_t count, loff_t *ppos)
342{
343	struct iowarrior *dev;
344	int retval = 0;
345	char *buf = NULL;	/* for IOW24 and IOW56 we need a buffer */
346	struct urb *int_out_urb = NULL;
347
348	dev = file->private_data;
349
350	mutex_lock(&dev->mutex);
351	/* verify that the device wasn't unplugged */
352	if (!dev->present) {
353		retval = -ENODEV;
354		goto exit;
355	}
356	dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
357		dev->minor, count);
358	/* if count is 0 we're already done */
359	if (count == 0) {
360		retval = 0;
361		goto exit;
362	}
363	/* We only accept full reports */
364	if (count != dev->report_size) {
365		retval = -EINVAL;
366		goto exit;
367	}
368	switch (dev->product_id) {
369	case USB_DEVICE_ID_CODEMERCS_IOW24:
370	case USB_DEVICE_ID_CODEMERCS_IOW24SAG:
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 = memdup_user(user_buffer, count);
376		if (IS_ERR(buf)) {
377			retval = PTR_ERR(buf);
378			goto exit;
379		}
380		retval = usb_set_report(dev->interface, 2, 0, buf, count);
381		kfree(buf);
382		goto exit;
 
383	case USB_DEVICE_ID_CODEMERCS_IOW56:
384	case USB_DEVICE_ID_CODEMERCS_IOW56AM:
385	case USB_DEVICE_ID_CODEMERCS_IOW28:
386	case USB_DEVICE_ID_CODEMERCS_IOW28L:
387	case USB_DEVICE_ID_CODEMERCS_IOW100:
388		/* The IOW56 uses asynchronous IO and more urbs */
389		if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
390			/* Wait until we are below the limit for submitted urbs */
391			if (file->f_flags & O_NONBLOCK) {
392				retval = -EAGAIN;
393				goto exit;
394			} else {
395				retval = wait_event_interruptible(dev->write_wait,
396								  (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
397				if (retval) {
398					/* we were interrupted by a signal */
399					retval = -ERESTART;
400					goto exit;
401				}
402				if (!dev->present) {
403					/* The device was unplugged */
404					retval = -ENODEV;
405					goto exit;
406				}
407				if (!dev->opened) {
408					/* We were closed while waiting for an URB */
409					retval = -ENODEV;
410					goto exit;
411				}
412			}
413		}
414		atomic_inc(&dev->write_busy);
415		int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
416		if (!int_out_urb) {
417			retval = -ENOMEM;
418			goto error_no_urb;
419		}
420		buf = usb_alloc_coherent(dev->udev, dev->report_size,
421					 GFP_KERNEL, &int_out_urb->transfer_dma);
422		if (!buf) {
423			retval = -ENOMEM;
424			dev_dbg(&dev->interface->dev,
425				"Unable to allocate buffer\n");
426			goto error_no_buffer;
427		}
428		usb_fill_int_urb(int_out_urb, dev->udev,
429				 usb_sndintpipe(dev->udev,
430						dev->int_out_endpoint->bEndpointAddress),
431				 buf, dev->report_size,
432				 iowarrior_write_callback, dev,
433				 dev->int_out_endpoint->bInterval);
434		int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
435		if (copy_from_user(buf, user_buffer, count)) {
436			retval = -EFAULT;
437			goto error;
438		}
439		usb_anchor_urb(int_out_urb, &dev->submitted);
440		retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
441		if (retval) {
442			dev_dbg(&dev->interface->dev,
443				"submit error %d for urb nr.%d\n",
444				retval, atomic_read(&dev->write_busy));
445			usb_unanchor_urb(int_out_urb);
446			goto error;
447		}
448		/* submit was ok */
449		retval = count;
450		usb_free_urb(int_out_urb);
451		goto exit;
 
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\n",
455			__func__, dev->product_id);
456		retval = -EFAULT;
457		goto exit;
 
458	}
459error:
460	usb_free_coherent(dev->udev, dev->report_size, buf,
461			  int_out_urb->transfer_dma);
462error_no_buffer:
463	usb_free_urb(int_out_urb);
464error_no_urb:
465	atomic_dec(&dev->write_busy);
466	wake_up_interruptible(&dev->write_wait);
467exit:
468	mutex_unlock(&dev->mutex);
469	return retval;
470}
471
472/*
473 *	iowarrior_ioctl
474 */
475static long iowarrior_ioctl(struct file *file, unsigned int cmd,
476							unsigned long arg)
477{
478	struct iowarrior *dev = NULL;
479	__u8 *buffer;
480	__u8 __user *user_buffer;
481	int retval;
482	int io_res;		/* checks for bytes read/written and copy_to/from_user results */
483
484	dev = file->private_data;
485	if (!dev)
486		return -ENODEV;
487
488	buffer = kzalloc(dev->report_size, GFP_KERNEL);
489	if (!buffer)
490		return -ENOMEM;
491
492	mutex_lock(&dev->mutex);
493
494	/* verify that the device wasn't unplugged */
495	if (!dev->present) {
496		retval = -ENODEV;
497		goto error_out;
498	}
499
500	dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n",
501		dev->minor, cmd, arg);
502
503	retval = 0;
504	io_res = 0;
505	switch (cmd) {
506	case IOW_WRITE:
507		if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
508		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG ||
509		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
510		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
511		    dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
512			user_buffer = (__u8 __user *)arg;
513			io_res = copy_from_user(buffer, user_buffer,
514						dev->report_size);
515			if (io_res) {
516				retval = -EFAULT;
517			} else {
518				io_res = usb_set_report(dev->interface, 2, 0,
519							buffer,
520							dev->report_size);
521				if (io_res < 0)
522					retval = io_res;
523			}
524		} else {
525			retval = -EINVAL;
526			dev_err(&dev->interface->dev,
527				"ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
528				dev->product_id);
529		}
530		break;
531	case IOW_READ:
532		user_buffer = (__u8 __user *)arg;
533		io_res = usb_get_report(dev->udev,
534					dev->interface->cur_altsetting, 1, 0,
535					buffer, dev->report_size);
536		if (io_res < 0)
537			retval = io_res;
538		else {
539			io_res = copy_to_user(user_buffer, buffer, dev->report_size);
540			if (io_res)
541				retval = -EFAULT;
542		}
543		break;
544	case IOW_GETINFO:
545		{
546			/* Report available information for the device */
547			struct iowarrior_info info;
548			/* needed for power consumption */
549			struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
550
551			memset(&info, 0, sizeof(info));
552			/* directly from the descriptor */
553			info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
554			info.product = dev->product_id;
555			info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
556
557			/* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
558			info.speed = dev->udev->speed;
559			info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
560			info.report_size = dev->report_size;
561
562			/* serial number string has been read earlier 8 chars or empty string */
563			memcpy(info.serial, dev->chip_serial,
564			       sizeof(dev->chip_serial));
565			if (cfg_descriptor == NULL) {
566				info.power = -1;	/* no information available */
567			} else {
568				/* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
569				info.power = cfg_descriptor->bMaxPower * 2;
570			}
571			io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
572					 sizeof(struct iowarrior_info));
573			if (io_res)
574				retval = -EFAULT;
575			break;
576		}
577	default:
578		/* return that we did not understand this ioctl call */
579		retval = -ENOTTY;
580		break;
581	}
582error_out:
583	/* unlock the device */
584	mutex_unlock(&dev->mutex);
585	kfree(buffer);
586	return retval;
587}
588
589/*
590 *	iowarrior_open
591 */
592static int iowarrior_open(struct inode *inode, struct file *file)
593{
594	struct iowarrior *dev = NULL;
595	struct usb_interface *interface;
596	int subminor;
597	int retval = 0;
598
599	subminor = iminor(inode);
600
601	interface = usb_find_interface(&iowarrior_driver, subminor);
602	if (!interface) {
603		pr_err("%s - error, can't find device for minor %d\n",
604		       __func__, subminor);
605		return -ENODEV;
606	}
607
608	dev = usb_get_intfdata(interface);
609	if (!dev)
610		return -ENODEV;
611
612	mutex_lock(&dev->mutex);
613
614	/* Only one process can open each device, no sharing. */
615	if (dev->opened) {
616		retval = -EBUSY;
617		goto out;
618	}
619
620	/* setup interrupt handler for receiving values */
621	if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
622		dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
623		retval = -EFAULT;
624		goto out;
625	}
626	/* increment our usage count for the driver */
627	++dev->opened;
628	/* save our object in the file's private structure */
629	file->private_data = dev;
630	retval = 0;
631
632out:
633	mutex_unlock(&dev->mutex);
634	return retval;
635}
636
637/*
638 *	iowarrior_release
639 */
640static int iowarrior_release(struct inode *inode, struct file *file)
641{
642	struct iowarrior *dev;
643	int retval = 0;
644
645	dev = file->private_data;
646	if (!dev)
647		return -ENODEV;
648
649	dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
650
651	/* lock our device */
652	mutex_lock(&dev->mutex);
653
654	if (dev->opened <= 0) {
655		retval = -ENODEV;	/* close called more than once */
656		mutex_unlock(&dev->mutex);
657	} else {
658		dev->opened = 0;	/* we're closing now */
659		retval = 0;
660		if (dev->present) {
661			/*
662			   The device is still connected so we only shutdown
663			   pending read-/write-ops.
664			 */
665			usb_kill_urb(dev->int_in_urb);
666			wake_up_interruptible(&dev->read_wait);
667			wake_up_interruptible(&dev->write_wait);
668			mutex_unlock(&dev->mutex);
669		} else {
670			/* The device was unplugged, cleanup resources */
671			mutex_unlock(&dev->mutex);
672			iowarrior_delete(dev);
673		}
674	}
675	return retval;
676}
677
678static __poll_t iowarrior_poll(struct file *file, poll_table * wait)
679{
680	struct iowarrior *dev = file->private_data;
681	__poll_t mask = 0;
682
683	if (!dev->present)
684		return EPOLLERR | EPOLLHUP;
685
686	poll_wait(file, &dev->read_wait, wait);
687	poll_wait(file, &dev->write_wait, wait);
688
689	if (!dev->present)
690		return EPOLLERR | EPOLLHUP;
691
692	if (read_index(dev) != -1)
693		mask |= EPOLLIN | EPOLLRDNORM;
694
695	if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
696		mask |= EPOLLOUT | EPOLLWRNORM;
697	return mask;
698}
699
700/*
701 * File operations needed when we register this driver.
702 * This assumes that this driver NEEDS file operations,
703 * of course, which means that the driver is expected
704 * to have a node in the /dev directory. If the USB
705 * device were for a network interface then the driver
706 * would use "struct net_driver" instead, and a serial
707 * device would use "struct tty_driver".
708 */
709static const struct file_operations iowarrior_fops = {
710	.owner = THIS_MODULE,
711	.write = iowarrior_write,
712	.read = iowarrior_read,
713	.unlocked_ioctl = iowarrior_ioctl,
714	.open = iowarrior_open,
715	.release = iowarrior_release,
716	.poll = iowarrior_poll,
717	.llseek = noop_llseek,
718};
719
720static char *iowarrior_devnode(const struct device *dev, umode_t *mode)
721{
722	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
723}
724
725/*
726 * usb class driver info in order to get a minor number from the usb core,
727 * and to have the device registered with devfs and the driver core
728 */
729static struct usb_class_driver iowarrior_class = {
730	.name = "iowarrior%d",
731	.devnode = iowarrior_devnode,
732	.fops = &iowarrior_fops,
733	.minor_base = IOWARRIOR_MINOR_BASE,
734};
735
736/*---------------------------------*/
737/*  probe and disconnect functions */
738/*---------------------------------*/
739/*
740 *	iowarrior_probe
741 *
742 *	Called by the usb core when a new device is connected that it thinks
743 *	this driver might be interested in.
744 */
745static int iowarrior_probe(struct usb_interface *interface,
746			   const struct usb_device_id *id)
747{
748	struct usb_device *udev = interface_to_usbdev(interface);
749	struct iowarrior *dev = NULL;
750	struct usb_host_interface *iface_desc;
751	int retval = -ENOMEM;
752	int res;
753
754	/* allocate memory for our device state and initialize it */
755	dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
756	if (!dev)
757		return retval;
758
759	mutex_init(&dev->mutex);
760
761	atomic_set(&dev->intr_idx, 0);
762	atomic_set(&dev->read_idx, 0);
763	atomic_set(&dev->overflow_flag, 0);
764	init_waitqueue_head(&dev->read_wait);
765	atomic_set(&dev->write_busy, 0);
766	init_waitqueue_head(&dev->write_wait);
767
768	dev->udev = udev;
769	dev->interface = usb_get_intf(interface);
770
771	iface_desc = interface->cur_altsetting;
772	dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
773
774	init_usb_anchor(&dev->submitted);
775
776	res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
777	if (res) {
778		dev_err(&interface->dev, "no interrupt-in endpoint found\n");
779		retval = res;
780		goto error;
781	}
782
783	if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) ||
784	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) ||
785	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) ||
786	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) ||
787	    (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) {
788		res = usb_find_last_int_out_endpoint(iface_desc,
789				&dev->int_out_endpoint);
790		if (res) {
791			dev_err(&interface->dev, "no interrupt-out endpoint found\n");
792			retval = res;
793			goto error;
794		}
795	}
796
797	/* we have to check the report_size often, so remember it in the endianness suitable for our machine */
798	dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
799
800	/*
801	 * Some devices need the report size to be different than the
802	 * endpoint size.
803	 */
804	if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
805		switch (dev->product_id) {
806		case USB_DEVICE_ID_CODEMERCS_IOW56:
807		case USB_DEVICE_ID_CODEMERCS_IOW56AM:
808			dev->report_size = 7;
809			break;
810
811		case USB_DEVICE_ID_CODEMERCS_IOW28:
812		case USB_DEVICE_ID_CODEMERCS_IOW28L:
813			dev->report_size = 4;
814			break;
815
816		case USB_DEVICE_ID_CODEMERCS_IOW100:
817			dev->report_size = 12;
818			break;
819		}
820	}
821
822	/* create the urb and buffer for reading */
823	dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
824	if (!dev->int_in_urb)
825		goto error;
826	dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
827	if (!dev->int_in_buffer)
828		goto error;
829	usb_fill_int_urb(dev->int_in_urb, dev->udev,
830			 usb_rcvintpipe(dev->udev,
831					dev->int_in_endpoint->bEndpointAddress),
832			 dev->int_in_buffer, dev->report_size,
833			 iowarrior_callback, dev,
834			 dev->int_in_endpoint->bInterval);
835	/* create an internal buffer for interrupt data from the device */
836	dev->read_queue =
837	    kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER,
838			  GFP_KERNEL);
839	if (!dev->read_queue)
840		goto error;
841	/* Get the serial-number of the chip */
842	memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
843	usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
844		   sizeof(dev->chip_serial));
845	if (strlen(dev->chip_serial) != 8)
846		memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
847
848	/* Set the idle timeout to 0, if this is interface 0 */
849	if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
850	    usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
851			    0x0A,
852			    USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
853			    0, NULL, 0, USB_CTRL_SET_TIMEOUT);
854	}
855	/* allow device read and ioctl */
856	dev->present = 1;
857
858	/* we can register the device now, as it is ready */
859	usb_set_intfdata(interface, dev);
860
861	retval = usb_register_dev(interface, &iowarrior_class);
862	if (retval) {
863		/* something prevented us from registering this driver */
864		dev_err(&interface->dev, "Not able to get a minor for this device.\n");
865		goto error;
866	}
867
868	dev->minor = interface->minor;
869
870	/* let the user know what node this device is now attached to */
871	dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
872		 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
873		 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
874	return retval;
875
876error:
877	iowarrior_delete(dev);
878	return retval;
879}
880
881/*
882 *	iowarrior_disconnect
883 *
884 *	Called by the usb core when the device is removed from the system.
885 */
886static void iowarrior_disconnect(struct usb_interface *interface)
887{
888	struct iowarrior *dev = usb_get_intfdata(interface);
889	int minor = dev->minor;
890
891	usb_deregister_dev(interface, &iowarrior_class);
892
893	mutex_lock(&dev->mutex);
894
895	/* prevent device read, write and ioctl */
896	dev->present = 0;
897
898	if (dev->opened) {
899		/* There is a process that holds a filedescriptor to the device ,
900		   so we only shutdown read-/write-ops going on.
901		   Deleting the device is postponed until close() was called.
902		 */
903		usb_kill_urb(dev->int_in_urb);
904		usb_kill_anchored_urbs(&dev->submitted);
905		wake_up_interruptible(&dev->read_wait);
906		wake_up_interruptible(&dev->write_wait);
907		mutex_unlock(&dev->mutex);
908	} else {
909		/* no process is using the device, cleanup now */
910		mutex_unlock(&dev->mutex);
911		iowarrior_delete(dev);
912	}
913
914	dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
915		 minor - IOWARRIOR_MINOR_BASE);
916}
917
918/* usb specific object needed to register this driver with the usb subsystem */
919static struct usb_driver iowarrior_driver = {
920	.name = "iowarrior",
921	.probe = iowarrior_probe,
922	.disconnect = iowarrior_disconnect,
923	.id_table = iowarrior_ids,
924};
925
926module_usb_driver(iowarrior_driver);