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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * drivers/usb/class/usbtmc.c - USB Test & Measurement class driver
4 *
5 * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany
6 * Copyright (C) 2008 Novell, Inc.
7 * Copyright (C) 2008 Greg Kroah-Hartman <[email protected]>
8 * Copyright (C) 2018 IVI Foundation, Inc.
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/fs.h>
16#include <linux/uaccess.h>
17#include <linux/kref.h>
18#include <linux/slab.h>
19#include <linux/poll.h>
20#include <linux/mutex.h>
21#include <linux/usb.h>
22#include <linux/compat.h>
23#include <linux/usb/tmc.h>
24
25/* Increment API VERSION when changing tmc.h with new flags or ioctls
26 * or when changing a significant behavior of the driver.
27 */
28#define USBTMC_API_VERSION (3)
29
30#define USBTMC_HEADER_SIZE 12
31#define USBTMC_MINOR_BASE 176
32
33/* Minimum USB timeout (in milliseconds) */
34#define USBTMC_MIN_TIMEOUT 100
35/* Default USB timeout (in milliseconds) */
36#define USBTMC_TIMEOUT 5000
37
38/* Max number of urbs used in write transfers */
39#define MAX_URBS_IN_FLIGHT 16
40/* I/O buffer size used in generic read/write functions */
41#define USBTMC_BUFSIZE (4096)
42
43/*
44 * Maximum number of read cycles to empty bulk in endpoint during CLEAR and
45 * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
46 * packet is never read.
47 */
48#define USBTMC_MAX_READS_TO_CLEAR_BULK_IN 100
49
50static const struct usb_device_id usbtmc_devices[] = {
51 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), },
52 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), },
53 { 0, } /* terminating entry */
54};
55MODULE_DEVICE_TABLE(usb, usbtmc_devices);
56
57/*
58 * This structure is the capabilities for the device
59 * See section 4.2.1.8 of the USBTMC specification,
60 * and section 4.2.2 of the USBTMC usb488 subclass
61 * specification for details.
62 */
63struct usbtmc_dev_capabilities {
64 __u8 interface_capabilities;
65 __u8 device_capabilities;
66 __u8 usb488_interface_capabilities;
67 __u8 usb488_device_capabilities;
68};
69
70/* This structure holds private data for each USBTMC device. One copy is
71 * allocated for each USBTMC device in the driver's probe function.
72 */
73struct usbtmc_device_data {
74 struct usb_device *usb_dev;
75 struct usb_interface *intf;
76 struct list_head file_list;
77
78 unsigned int bulk_in;
79 unsigned int bulk_out;
80
81 u8 bTag;
82 u8 bTag_last_write; /* needed for abort */
83 u8 bTag_last_read; /* needed for abort */
84
85 /* packet size of IN bulk */
86 u16 wMaxPacketSize;
87
88 /* data for interrupt in endpoint handling */
89 u8 bNotify1;
90 u8 bNotify2;
91 u16 ifnum;
92 u8 iin_bTag;
93 u8 *iin_buffer;
94 atomic_t iin_data_valid;
95 unsigned int iin_ep;
96 int iin_ep_present;
97 int iin_interval;
98 struct urb *iin_urb;
99 u16 iin_wMaxPacketSize;
100
101 /* coalesced usb488_caps from usbtmc_dev_capabilities */
102 __u8 usb488_caps;
103
104 bool zombie; /* fd of disconnected device */
105
106 struct usbtmc_dev_capabilities capabilities;
107 struct kref kref;
108 struct mutex io_mutex; /* only one i/o function running at a time */
109 wait_queue_head_t waitq;
110 struct fasync_struct *fasync;
111 spinlock_t dev_lock; /* lock for file_list */
112};
113#define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref)
114
115/*
116 * This structure holds private data for each USBTMC file handle.
117 */
118struct usbtmc_file_data {
119 struct usbtmc_device_data *data;
120 struct list_head file_elem;
121
122 u32 timeout;
123 u8 srq_byte;
124 atomic_t srq_asserted;
125 atomic_t closing;
126 u8 bmTransferAttributes; /* member of DEV_DEP_MSG_IN */
127
128 u8 eom_val;
129 u8 term_char;
130 bool term_char_enabled;
131 bool auto_abort;
132
133 spinlock_t err_lock; /* lock for errors */
134
135 struct usb_anchor submitted;
136
137 /* data for generic_write */
138 struct semaphore limit_write_sem;
139 u32 out_transfer_size;
140 int out_status;
141
142 /* data for generic_read */
143 u32 in_transfer_size;
144 int in_status;
145 int in_urbs_used;
146 struct usb_anchor in_anchor;
147 wait_queue_head_t wait_bulk_in;
148};
149
150/* Forward declarations */
151static struct usb_driver usbtmc_driver;
152static void usbtmc_draw_down(struct usbtmc_file_data *file_data);
153
154static void usbtmc_delete(struct kref *kref)
155{
156 struct usbtmc_device_data *data = to_usbtmc_data(kref);
157
158 usb_put_dev(data->usb_dev);
159 kfree(data);
160}
161
162static int usbtmc_open(struct inode *inode, struct file *filp)
163{
164 struct usb_interface *intf;
165 struct usbtmc_device_data *data;
166 struct usbtmc_file_data *file_data;
167
168 intf = usb_find_interface(&usbtmc_driver, iminor(inode));
169 if (!intf) {
170 pr_err("can not find device for minor %d", iminor(inode));
171 return -ENODEV;
172 }
173
174 file_data = kzalloc_obj(*file_data);
175 if (!file_data)
176 return -ENOMEM;
177
178 spin_lock_init(&file_data->err_lock);
179 sema_init(&file_data->limit_write_sem, MAX_URBS_IN_FLIGHT);
180 init_usb_anchor(&file_data->submitted);
181 init_usb_anchor(&file_data->in_anchor);
182 init_waitqueue_head(&file_data->wait_bulk_in);
183
184 data = usb_get_intfdata(intf);
185 /* Protect reference to data from file structure until release */
186 kref_get(&data->kref);
187
188 mutex_lock(&data->io_mutex);
189 file_data->data = data;
190
191 atomic_set(&file_data->closing, 0);
192
193 file_data->timeout = USBTMC_TIMEOUT;
194 file_data->term_char = '\n';
195 file_data->term_char_enabled = 0;
196 file_data->auto_abort = 0;
197 file_data->eom_val = 1;
198
199 INIT_LIST_HEAD(&file_data->file_elem);
200 spin_lock_irq(&data->dev_lock);
201 list_add_tail(&file_data->file_elem, &data->file_list);
202 spin_unlock_irq(&data->dev_lock);
203 mutex_unlock(&data->io_mutex);
204
205 /* Store pointer in file structure's private data field */
206 filp->private_data = file_data;
207
208 return 0;
209}
210
211/*
212 * usbtmc_flush - called before file handle is closed
213 */
214static int usbtmc_flush(struct file *file, fl_owner_t id)
215{
216 struct usbtmc_file_data *file_data;
217 struct usbtmc_device_data *data;
218
219 file_data = file->private_data;
220 if (file_data == NULL)
221 return -ENODEV;
222
223 atomic_set(&file_data->closing, 1);
224 data = file_data->data;
225
226 /* wait for io to stop */
227 mutex_lock(&data->io_mutex);
228
229 usbtmc_draw_down(file_data);
230
231 spin_lock_irq(&file_data->err_lock);
232 file_data->in_status = 0;
233 file_data->in_transfer_size = 0;
234 file_data->in_urbs_used = 0;
235 file_data->out_status = 0;
236 file_data->out_transfer_size = 0;
237 spin_unlock_irq(&file_data->err_lock);
238
239 wake_up_interruptible_all(&data->waitq);
240 mutex_unlock(&data->io_mutex);
241
242 return 0;
243}
244
245static int usbtmc_release(struct inode *inode, struct file *file)
246{
247 struct usbtmc_file_data *file_data = file->private_data;
248
249 /* prevent IO _AND_ usbtmc_interrupt */
250 mutex_lock(&file_data->data->io_mutex);
251 spin_lock_irq(&file_data->data->dev_lock);
252
253 list_del(&file_data->file_elem);
254
255 spin_unlock_irq(&file_data->data->dev_lock);
256
257 /* flush anchored URBs */
258 usbtmc_draw_down(file_data);
259 mutex_unlock(&file_data->data->io_mutex);
260
261 kref_put(&file_data->data->kref, usbtmc_delete);
262 file_data->data = NULL;
263 kfree(file_data);
264 return 0;
265}
266
267static int usbtmc_ioctl_abort_bulk_in_tag(struct usbtmc_device_data *data,
268 u8 tag)
269{
270 u8 *buffer;
271 struct device *dev;
272 int rv;
273 int n;
274 int actual;
275
276 dev = &data->intf->dev;
277 buffer = kmalloc(USBTMC_BUFSIZE, GFP_KERNEL);
278 if (!buffer)
279 return -ENOMEM;
280
281 rv = usb_control_msg(data->usb_dev,
282 usb_rcvctrlpipe(data->usb_dev, 0),
283 USBTMC_REQUEST_INITIATE_ABORT_BULK_IN,
284 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
285 tag, data->bulk_in,
286 buffer, 2, USB_CTRL_GET_TIMEOUT);
287
288 if (rv < 0) {
289 dev_err(dev, "usb_control_msg returned %d\n", rv);
290 goto exit;
291 }
292
293 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x with tag %02x\n",
294 buffer[0], buffer[1]);
295
296 if (buffer[0] == USBTMC_STATUS_FAILED) {
297 /* No transfer in progress and the Bulk-OUT FIFO is empty. */
298 rv = 0;
299 goto exit;
300 }
301
302 if (buffer[0] == USBTMC_STATUS_TRANSFER_NOT_IN_PROGRESS) {
303 /* The device returns this status if either:
304 * - There is a transfer in progress, but the specified bTag
305 * does not match.
306 * - There is no transfer in progress, but the Bulk-OUT FIFO
307 * is not empty.
308 */
309 rv = -ENOMSG;
310 goto exit;
311 }
312
313 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
314 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n",
315 buffer[0]);
316 rv = -EPERM;
317 goto exit;
318 }
319
320 n = 0;
321
322usbtmc_abort_bulk_in_status:
323 dev_dbg(dev, "Reading from bulk in EP\n");
324
325 /* Data must be present. So use low timeout 300 ms */
326 actual = 0;
327 rv = usb_bulk_msg(data->usb_dev,
328 usb_rcvbulkpipe(data->usb_dev,
329 data->bulk_in),
330 buffer, USBTMC_BUFSIZE,
331 &actual, 300);
332
333 print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, 16, 1,
334 buffer, actual, true);
335
336 n++;
337
338 if (rv < 0) {
339 dev_err(dev, "usb_bulk_msg returned %d\n", rv);
340 if (rv != -ETIMEDOUT)
341 goto exit;
342 }
343
344 if (actual == USBTMC_BUFSIZE)
345 goto usbtmc_abort_bulk_in_status;
346
347 if (n >= USBTMC_MAX_READS_TO_CLEAR_BULK_IN) {
348 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
349 USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
350 rv = -EPERM;
351 goto exit;
352 }
353
354 rv = usb_control_msg(data->usb_dev,
355 usb_rcvctrlpipe(data->usb_dev, 0),
356 USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS,
357 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
358 0, data->bulk_in, buffer, 0x08,
359 USB_CTRL_GET_TIMEOUT);
360
361 if (rv < 0) {
362 dev_err(dev, "usb_control_msg returned %d\n", rv);
363 goto exit;
364 }
365
366 dev_dbg(dev, "CHECK_ABORT_BULK_IN returned %x\n", buffer[0]);
367
368 if (buffer[0] == USBTMC_STATUS_SUCCESS) {
369 rv = 0;
370 goto exit;
371 }
372
373 if (buffer[0] != USBTMC_STATUS_PENDING) {
374 dev_err(dev, "CHECK_ABORT_BULK_IN returned %x\n", buffer[0]);
375 rv = -EPERM;
376 goto exit;
377 }
378
379 if ((buffer[1] & 1) > 0) {
380 /* The device has 1 or more queued packets the Host can read */
381 goto usbtmc_abort_bulk_in_status;
382 }
383
384 /* The Host must send CHECK_ABORT_BULK_IN_STATUS at a later time. */
385 rv = -EAGAIN;
386exit:
387 kfree(buffer);
388 return rv;
389}
390
391static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data)
392{
393 return usbtmc_ioctl_abort_bulk_in_tag(data, data->bTag_last_read);
394}
395
396static int usbtmc_ioctl_abort_bulk_out_tag(struct usbtmc_device_data *data,
397 u8 tag)
398{
399 struct device *dev;
400 u8 *buffer;
401 int rv;
402 int n;
403
404 dev = &data->intf->dev;
405
406 buffer = kmalloc(8, GFP_KERNEL);
407 if (!buffer)
408 return -ENOMEM;
409
410 rv = usb_control_msg(data->usb_dev,
411 usb_rcvctrlpipe(data->usb_dev, 0),
412 USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT,
413 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
414 tag, data->bulk_out,
415 buffer, 2, USB_CTRL_GET_TIMEOUT);
416
417 if (rv < 0) {
418 dev_err(dev, "usb_control_msg returned %d\n", rv);
419 goto exit;
420 }
421
422 dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]);
423
424 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
425 dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n",
426 buffer[0]);
427 rv = -EPERM;
428 goto exit;
429 }
430
431 n = 0;
432
433usbtmc_abort_bulk_out_check_status:
434 /* do not stress device with subsequent requests */
435 msleep(50);
436 rv = usb_control_msg(data->usb_dev,
437 usb_rcvctrlpipe(data->usb_dev, 0),
438 USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS,
439 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
440 0, data->bulk_out, buffer, 0x08,
441 USB_CTRL_GET_TIMEOUT);
442 n++;
443 if (rv < 0) {
444 dev_err(dev, "usb_control_msg returned %d\n", rv);
445 goto exit;
446 }
447
448 dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]);
449
450 if (buffer[0] == USBTMC_STATUS_SUCCESS)
451 goto usbtmc_abort_bulk_out_clear_halt;
452
453 if ((buffer[0] == USBTMC_STATUS_PENDING) &&
454 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN))
455 goto usbtmc_abort_bulk_out_check_status;
456
457 rv = -EPERM;
458 goto exit;
459
460usbtmc_abort_bulk_out_clear_halt:
461 rv = usb_clear_halt(data->usb_dev,
462 usb_sndbulkpipe(data->usb_dev, data->bulk_out));
463
464 if (rv < 0) {
465 dev_err(dev, "usb_control_msg returned %d\n", rv);
466 goto exit;
467 }
468 rv = 0;
469
470exit:
471 kfree(buffer);
472 return rv;
473}
474
475static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
476{
477 return usbtmc_ioctl_abort_bulk_out_tag(data, data->bTag_last_write);
478}
479
480static int usbtmc_get_stb(struct usbtmc_file_data *file_data, __u8 *stb)
481{
482 struct usbtmc_device_data *data = file_data->data;
483 struct device *dev = &data->intf->dev;
484 u8 *buffer;
485 u8 tag;
486 int rv;
487 long wait_rv;
488 unsigned long expire;
489
490 dev_dbg(dev, "Enter ioctl_read_stb iin_ep_present: %d\n",
491 data->iin_ep_present);
492
493 buffer = kmalloc(8, GFP_KERNEL);
494 if (!buffer)
495 return -ENOMEM;
496
497 atomic_set(&data->iin_data_valid, 0);
498
499 rv = usb_control_msg(data->usb_dev,
500 usb_rcvctrlpipe(data->usb_dev, 0),
501 USBTMC488_REQUEST_READ_STATUS_BYTE,
502 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
503 data->iin_bTag,
504 data->ifnum,
505 buffer, 0x03, USB_CTRL_GET_TIMEOUT);
506 if (rv < 0) {
507 dev_err(dev, "stb usb_control_msg returned %d\n", rv);
508 goto exit;
509 }
510
511 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
512 dev_err(dev, "control status returned %x\n", buffer[0]);
513 rv = -EIO;
514 goto exit;
515 }
516
517 if (data->iin_ep_present) {
518 expire = msecs_to_jiffies(file_data->timeout);
519 wait_rv = wait_event_interruptible_timeout(
520 data->waitq,
521 atomic_read(&data->iin_data_valid) != 0,
522 expire);
523 if (wait_rv < 0) {
524 dev_dbg(dev, "wait interrupted %ld\n", wait_rv);
525 rv = wait_rv;
526 goto exit;
527 }
528
529 if (wait_rv == 0) {
530 dev_dbg(dev, "wait timed out\n");
531 rv = -ETIMEDOUT;
532 goto exit;
533 }
534
535 tag = data->bNotify1 & 0x7f;
536 if (tag != data->iin_bTag) {
537 dev_err(dev, "expected bTag %x got %x\n",
538 data->iin_bTag, tag);
539 }
540
541 *stb = data->bNotify2;
542 } else {
543 *stb = buffer[2];
544 }
545
546 dev_dbg(dev, "stb:0x%02x received %d\n", (unsigned int)*stb, rv);
547
548 rv = 0;
549
550 exit:
551 /* bump interrupt bTag */
552 data->iin_bTag += 1;
553 if (data->iin_bTag > 127)
554 /* 1 is for SRQ see USBTMC-USB488 subclass spec section 4.3.1 */
555 data->iin_bTag = 2;
556
557 kfree(buffer);
558 return rv;
559}
560
561static int usbtmc488_ioctl_read_stb(struct usbtmc_file_data *file_data,
562 void __user *arg)
563{
564 int srq_asserted = 0;
565 __u8 stb;
566 int rv;
567
568 rv = usbtmc_get_stb(file_data, &stb);
569
570 if (rv < 0)
571 return rv;
572
573 srq_asserted = atomic_xchg(&file_data->srq_asserted, srq_asserted);
574 if (srq_asserted)
575 stb |= 0x40; /* Set RQS bit */
576
577 rv = put_user(stb, (__u8 __user *)arg);
578
579 return rv;
580
581}
582
583static int usbtmc_ioctl_get_srq_stb(struct usbtmc_file_data *file_data,
584 void __user *arg)
585{
586 struct usbtmc_device_data *data = file_data->data;
587 struct device *dev = &data->intf->dev;
588 int srq_asserted = 0;
589 __u8 stb = 0;
590 int rv;
591
592 spin_lock_irq(&data->dev_lock);
593 srq_asserted = atomic_xchg(&file_data->srq_asserted, srq_asserted);
594
595 if (srq_asserted) {
596 stb = file_data->srq_byte;
597 spin_unlock_irq(&data->dev_lock);
598 rv = put_user(stb, (__u8 __user *)arg);
599 } else {
600 spin_unlock_irq(&data->dev_lock);
601 rv = -ENOMSG;
602 }
603
604 dev_dbg(dev, "stb:0x%02x with srq received %d\n", (unsigned int)stb, rv);
605
606 return rv;
607}
608
609static int usbtmc488_ioctl_wait_srq(struct usbtmc_file_data *file_data,
610 __u32 __user *arg)
611{
612 struct usbtmc_device_data *data = file_data->data;
613 struct device *dev = &data->intf->dev;
614 u32 timeout;
615 unsigned long expire;
616 long wait_rv;
617
618 if (!data->iin_ep_present) {
619 dev_dbg(dev, "no interrupt endpoint present\n");
620 return -EFAULT;
621 }
622
623 if (get_user(timeout, arg))
624 return -EFAULT;
625
626 expire = msecs_to_jiffies(timeout);
627
628 mutex_unlock(&data->io_mutex);
629
630 wait_rv = wait_event_interruptible_timeout(
631 data->waitq,
632 atomic_read(&file_data->srq_asserted) != 0 ||
633 atomic_read(&file_data->closing),
634 expire);
635
636 mutex_lock(&data->io_mutex);
637
638 /* Note! disconnect or close could be called in the meantime */
639 if (atomic_read(&file_data->closing) || data->zombie)
640 return -ENODEV;
641
642 if (wait_rv < 0) {
643 dev_dbg(dev, "%s - wait interrupted %ld\n", __func__, wait_rv);
644 return wait_rv;
645 }
646
647 if (wait_rv == 0) {
648 dev_dbg(dev, "%s - wait timed out\n", __func__);
649 return -ETIMEDOUT;
650 }
651
652 dev_dbg(dev, "%s - srq asserted\n", __func__);
653 return 0;
654}
655
656static int usbtmc488_ioctl_simple(struct usbtmc_device_data *data,
657 void __user *arg, unsigned int cmd)
658{
659 struct device *dev = &data->intf->dev;
660 __u8 val;
661 u8 *buffer;
662 u16 wValue;
663 int rv;
664
665 if (!(data->usb488_caps & USBTMC488_CAPABILITY_SIMPLE))
666 return -EINVAL;
667
668 buffer = kmalloc(8, GFP_KERNEL);
669 if (!buffer)
670 return -ENOMEM;
671
672 if (cmd == USBTMC488_REQUEST_REN_CONTROL) {
673 rv = copy_from_user(&val, arg, sizeof(val));
674 if (rv) {
675 rv = -EFAULT;
676 goto exit;
677 }
678 wValue = val ? 1 : 0;
679 } else {
680 wValue = 0;
681 }
682
683 rv = usb_control_msg(data->usb_dev,
684 usb_rcvctrlpipe(data->usb_dev, 0),
685 cmd,
686 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
687 wValue,
688 data->ifnum,
689 buffer, 0x01, USB_CTRL_GET_TIMEOUT);
690 if (rv < 0) {
691 dev_err(dev, "simple usb_control_msg failed %d\n", rv);
692 goto exit;
693 } else if (rv != 1) {
694 dev_warn(dev, "simple usb_control_msg returned %d\n", rv);
695 rv = -EIO;
696 goto exit;
697 }
698
699 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
700 dev_err(dev, "simple control status returned %x\n", buffer[0]);
701 rv = -EIO;
702 goto exit;
703 }
704 rv = 0;
705
706 exit:
707 kfree(buffer);
708 return rv;
709}
710
711/*
712 * Sends a TRIGGER Bulk-OUT command message
713 * See the USBTMC-USB488 specification, Table 2.
714 *
715 * Also updates bTag_last_write.
716 */
717static int usbtmc488_ioctl_trigger(struct usbtmc_file_data *file_data)
718{
719 struct usbtmc_device_data *data = file_data->data;
720 int retval;
721 u8 *buffer;
722 int actual;
723
724 buffer = kzalloc(USBTMC_HEADER_SIZE, GFP_KERNEL);
725 if (!buffer)
726 return -ENOMEM;
727
728 buffer[0] = 128;
729 buffer[1] = data->bTag;
730 buffer[2] = ~data->bTag;
731
732 retval = usb_bulk_msg_killable(data->usb_dev,
733 usb_sndbulkpipe(data->usb_dev,
734 data->bulk_out),
735 buffer, USBTMC_HEADER_SIZE,
736 &actual, file_data->timeout);
737
738 /* Store bTag (in case we need to abort) */
739 data->bTag_last_write = data->bTag;
740
741 /* Increment bTag -- and increment again if zero */
742 data->bTag++;
743 if (!data->bTag)
744 data->bTag++;
745
746 kfree(buffer);
747 if (retval < 0) {
748 dev_err(&data->intf->dev, "%s returned %d\n",
749 __func__, retval);
750 return retval;
751 }
752
753 return 0;
754}
755
756static struct urb *usbtmc_create_urb(void)
757{
758 const size_t bufsize = USBTMC_BUFSIZE;
759 u8 *dmabuf = NULL;
760 struct urb *urb = usb_alloc_urb(0, GFP_KERNEL);
761
762 if (!urb)
763 return NULL;
764
765 dmabuf = kzalloc(bufsize, GFP_KERNEL);
766 if (!dmabuf) {
767 usb_free_urb(urb);
768 return NULL;
769 }
770
771 urb->transfer_buffer = dmabuf;
772 urb->transfer_buffer_length = bufsize;
773 urb->transfer_flags |= URB_FREE_BUFFER;
774 return urb;
775}
776
777static void usbtmc_read_bulk_cb(struct urb *urb)
778{
779 struct usbtmc_file_data *file_data = urb->context;
780 int status = urb->status;
781 unsigned long flags;
782
783 /* sync/async unlink faults aren't errors */
784 if (status) {
785 if (!(/* status == -ENOENT || */
786 status == -ECONNRESET ||
787 status == -EREMOTEIO || /* Short packet */
788 status == -ESHUTDOWN))
789 dev_err(&file_data->data->intf->dev,
790 "%s - nonzero read bulk status received: %d\n",
791 __func__, status);
792
793 spin_lock_irqsave(&file_data->err_lock, flags);
794 if (!file_data->in_status)
795 file_data->in_status = status;
796 spin_unlock_irqrestore(&file_data->err_lock, flags);
797 }
798
799 spin_lock_irqsave(&file_data->err_lock, flags);
800 file_data->in_transfer_size += urb->actual_length;
801 dev_dbg(&file_data->data->intf->dev,
802 "%s - total size: %u current: %d status: %d\n",
803 __func__, file_data->in_transfer_size,
804 urb->actual_length, status);
805 spin_unlock_irqrestore(&file_data->err_lock, flags);
806 usb_anchor_urb(urb, &file_data->in_anchor);
807
808 wake_up_interruptible(&file_data->wait_bulk_in);
809 wake_up_interruptible(&file_data->data->waitq);
810}
811
812static inline bool usbtmc_do_transfer(struct usbtmc_file_data *file_data)
813{
814 bool data_or_error;
815
816 spin_lock_irq(&file_data->err_lock);
817 data_or_error = !usb_anchor_empty(&file_data->in_anchor)
818 || file_data->in_status;
819 spin_unlock_irq(&file_data->err_lock);
820 dev_dbg(&file_data->data->intf->dev, "%s: returns %d\n", __func__,
821 data_or_error);
822 return data_or_error;
823}
824
825static ssize_t usbtmc_generic_read(struct usbtmc_file_data *file_data,
826 void __user *user_buffer,
827 u32 transfer_size,
828 u32 *transferred,
829 u32 flags)
830{
831 struct usbtmc_device_data *data = file_data->data;
832 struct device *dev = &data->intf->dev;
833 u32 done = 0;
834 u32 remaining;
835 const u32 bufsize = USBTMC_BUFSIZE;
836 int retval = 0;
837 u32 max_transfer_size;
838 unsigned long expire;
839 int bufcount = 1;
840 int again = 0;
841 long wait_rv;
842
843 /* mutex already locked */
844
845 *transferred = done;
846
847 max_transfer_size = transfer_size;
848
849 if (flags & USBTMC_FLAG_IGNORE_TRAILER) {
850 /* The device may send extra alignment bytes (up to
851 * wMaxPacketSize – 1) to avoid sending a zero-length
852 * packet
853 */
854 remaining = transfer_size;
855 if ((max_transfer_size % data->wMaxPacketSize) == 0)
856 max_transfer_size += (data->wMaxPacketSize - 1);
857 } else {
858 /* round down to bufsize to avoid truncated data left */
859 if (max_transfer_size > bufsize) {
860 max_transfer_size =
861 roundup(max_transfer_size + 1 - bufsize,
862 bufsize);
863 }
864 remaining = max_transfer_size;
865 }
866
867 spin_lock_irq(&file_data->err_lock);
868
869 if (file_data->in_status) {
870 /* return the very first error */
871 retval = file_data->in_status;
872 spin_unlock_irq(&file_data->err_lock);
873 goto error;
874 }
875
876 if (flags & USBTMC_FLAG_ASYNC) {
877 if (usb_anchor_empty(&file_data->in_anchor))
878 again = 1;
879
880 if (file_data->in_urbs_used == 0) {
881 file_data->in_transfer_size = 0;
882 file_data->in_status = 0;
883 }
884 } else {
885 file_data->in_transfer_size = 0;
886 file_data->in_status = 0;
887 }
888
889 if (max_transfer_size == 0) {
890 bufcount = 0;
891 } else {
892 bufcount = roundup(max_transfer_size, bufsize) / bufsize;
893 if (bufcount > file_data->in_urbs_used)
894 bufcount -= file_data->in_urbs_used;
895 else
896 bufcount = 0;
897
898 if (bufcount + file_data->in_urbs_used > MAX_URBS_IN_FLIGHT) {
899 bufcount = MAX_URBS_IN_FLIGHT -
900 file_data->in_urbs_used;
901 }
902 }
903 spin_unlock_irq(&file_data->err_lock);
904
905 dev_dbg(dev, "%s: requested=%u flags=0x%X size=%u bufs=%d used=%d\n",
906 __func__, transfer_size, flags,
907 max_transfer_size, bufcount, file_data->in_urbs_used);
908
909 while (bufcount > 0) {
910 u8 *dmabuf = NULL;
911 struct urb *urb = usbtmc_create_urb();
912
913 if (!urb) {
914 retval = -ENOMEM;
915 goto error;
916 }
917
918 dmabuf = urb->transfer_buffer;
919
920 usb_fill_bulk_urb(urb, data->usb_dev,
921 usb_rcvbulkpipe(data->usb_dev, data->bulk_in),
922 dmabuf, bufsize,
923 usbtmc_read_bulk_cb, file_data);
924
925 usb_anchor_urb(urb, &file_data->submitted);
926 retval = usb_submit_urb(urb, GFP_KERNEL);
927 /* urb is anchored. We can release our reference. */
928 usb_free_urb(urb);
929 if (unlikely(retval)) {
930 usb_unanchor_urb(urb);
931 goto error;
932 }
933 file_data->in_urbs_used++;
934 bufcount--;
935 }
936
937 if (again) {
938 dev_dbg(dev, "%s: ret=again\n", __func__);
939 return -EAGAIN;
940 }
941
942 if (user_buffer == NULL)
943 return -EINVAL;
944
945 expire = msecs_to_jiffies(file_data->timeout);
946
947 while (max_transfer_size > 0) {
948 u32 this_part;
949 struct urb *urb = NULL;
950
951 if (!(flags & USBTMC_FLAG_ASYNC)) {
952 dev_dbg(dev, "%s: before wait time %lu\n",
953 __func__, expire);
954 wait_rv = wait_event_interruptible_timeout(
955 file_data->wait_bulk_in,
956 usbtmc_do_transfer(file_data),
957 expire);
958
959 dev_dbg(dev, "%s: wait returned %ld\n",
960 __func__, wait_rv);
961
962 if (wait_rv < 0) {
963 retval = wait_rv;
964 goto error;
965 }
966
967 if (wait_rv == 0) {
968 retval = -ETIMEDOUT;
969 goto error;
970 }
971
972 }
973
974 urb = usb_get_from_anchor(&file_data->in_anchor);
975 if (!urb) {
976 if (!(flags & USBTMC_FLAG_ASYNC)) {
977 /* synchronous case: must not happen */
978 retval = -EFAULT;
979 goto error;
980 }
981
982 /* asynchronous case: ready, do not block or wait */
983 *transferred = done;
984 dev_dbg(dev, "%s: (async) done=%u ret=0\n",
985 __func__, done);
986 return 0;
987 }
988
989 file_data->in_urbs_used--;
990
991 if (max_transfer_size > urb->actual_length)
992 max_transfer_size -= urb->actual_length;
993 else
994 max_transfer_size = 0;
995
996 if (remaining > urb->actual_length)
997 this_part = urb->actual_length;
998 else
999 this_part = remaining;
1000
1001 print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, 16, 1,
1002 urb->transfer_buffer, urb->actual_length, true);
1003
1004 if (copy_to_user(user_buffer + done,
1005 urb->transfer_buffer, this_part)) {
1006 usb_free_urb(urb);
1007 retval = -EFAULT;
1008 goto error;
1009 }
1010
1011 remaining -= this_part;
1012 done += this_part;
1013
1014 spin_lock_irq(&file_data->err_lock);
1015 if (urb->status) {
1016 /* return the very first error */
1017 retval = file_data->in_status;
1018 spin_unlock_irq(&file_data->err_lock);
1019 usb_free_urb(urb);
1020 goto error;
1021 }
1022 spin_unlock_irq(&file_data->err_lock);
1023
1024 if (urb->actual_length < bufsize) {
1025 /* short packet or ZLP received => ready */
1026 usb_free_urb(urb);
1027 retval = 1;
1028 break;
1029 }
1030
1031 if (!(flags & USBTMC_FLAG_ASYNC) &&
1032 max_transfer_size > (bufsize * file_data->in_urbs_used)) {
1033 /* resubmit, since other buffers still not enough */
1034 usb_anchor_urb(urb, &file_data->submitted);
1035 retval = usb_submit_urb(urb, GFP_KERNEL);
1036 if (unlikely(retval)) {
1037 usb_unanchor_urb(urb);
1038 usb_free_urb(urb);
1039 goto error;
1040 }
1041 file_data->in_urbs_used++;
1042 }
1043 usb_free_urb(urb);
1044 retval = 0;
1045 }
1046
1047error:
1048 *transferred = done;
1049
1050 dev_dbg(dev, "%s: before kill\n", __func__);
1051 /* Attention: killing urbs can take long time (2 ms) */
1052 usb_kill_anchored_urbs(&file_data->submitted);
1053 dev_dbg(dev, "%s: after kill\n", __func__);
1054 usb_scuttle_anchored_urbs(&file_data->in_anchor);
1055 file_data->in_urbs_used = 0;
1056 file_data->in_status = 0; /* no spinlock needed here */
1057 dev_dbg(dev, "%s: done=%u ret=%d\n", __func__, done, retval);
1058
1059 return retval;
1060}
1061
1062static ssize_t usbtmc_ioctl_generic_read(struct usbtmc_file_data *file_data,
1063 void __user *arg)
1064{
1065 struct usbtmc_message msg;
1066 ssize_t retval = 0;
1067
1068 /* mutex already locked */
1069
1070 if (copy_from_user(&msg, arg, sizeof(struct usbtmc_message)))
1071 return -EFAULT;
1072
1073 retval = usbtmc_generic_read(file_data, msg.message,
1074 msg.transfer_size, &msg.transferred,
1075 msg.flags);
1076
1077 if (put_user(msg.transferred,
1078 &((struct usbtmc_message __user *)arg)->transferred))
1079 return -EFAULT;
1080
1081 return retval;
1082}
1083
1084static void usbtmc_write_bulk_cb(struct urb *urb)
1085{
1086 struct usbtmc_file_data *file_data = urb->context;
1087 int wakeup = 0;
1088 unsigned long flags;
1089
1090 spin_lock_irqsave(&file_data->err_lock, flags);
1091 file_data->out_transfer_size += urb->actual_length;
1092
1093 /* sync/async unlink faults aren't errors */
1094 if (urb->status) {
1095 if (!(urb->status == -ENOENT ||
1096 urb->status == -ECONNRESET ||
1097 urb->status == -ESHUTDOWN))
1098 dev_err(&file_data->data->intf->dev,
1099 "%s - nonzero write bulk status received: %d\n",
1100 __func__, urb->status);
1101
1102 if (!file_data->out_status) {
1103 file_data->out_status = urb->status;
1104 wakeup = 1;
1105 }
1106 }
1107 spin_unlock_irqrestore(&file_data->err_lock, flags);
1108
1109 dev_dbg(&file_data->data->intf->dev,
1110 "%s - write bulk total size: %u\n",
1111 __func__, file_data->out_transfer_size);
1112
1113 up(&file_data->limit_write_sem);
1114 if (usb_anchor_empty(&file_data->submitted) || wakeup)
1115 wake_up_interruptible(&file_data->data->waitq);
1116}
1117
1118static ssize_t usbtmc_generic_write(struct usbtmc_file_data *file_data,
1119 const void __user *user_buffer,
1120 u32 transfer_size,
1121 u32 *transferred,
1122 u32 flags)
1123{
1124 struct usbtmc_device_data *data = file_data->data;
1125 struct device *dev;
1126 u32 done = 0;
1127 u32 remaining;
1128 unsigned long expire;
1129 const u32 bufsize = USBTMC_BUFSIZE;
1130 struct urb *urb = NULL;
1131 int retval = 0;
1132 u32 timeout;
1133
1134 *transferred = 0;
1135
1136 /* Get pointer to private data structure */
1137 dev = &data->intf->dev;
1138
1139 dev_dbg(dev, "%s: size=%u flags=0x%X sema=%u\n",
1140 __func__, transfer_size, flags,
1141 file_data->limit_write_sem.count);
1142
1143 if (flags & USBTMC_FLAG_APPEND) {
1144 spin_lock_irq(&file_data->err_lock);
1145 retval = file_data->out_status;
1146 spin_unlock_irq(&file_data->err_lock);
1147 if (retval < 0)
1148 return retval;
1149 } else {
1150 spin_lock_irq(&file_data->err_lock);
1151 file_data->out_transfer_size = 0;
1152 file_data->out_status = 0;
1153 spin_unlock_irq(&file_data->err_lock);
1154 }
1155
1156 remaining = transfer_size;
1157 if (remaining > INT_MAX)
1158 remaining = INT_MAX;
1159
1160 timeout = file_data->timeout;
1161 expire = msecs_to_jiffies(timeout);
1162
1163 while (remaining > 0) {
1164 u32 this_part, aligned;
1165 u8 *buffer = NULL;
1166
1167 if (flags & USBTMC_FLAG_ASYNC) {
1168 if (down_trylock(&file_data->limit_write_sem)) {
1169 retval = (done)?(0):(-EAGAIN);
1170 goto exit;
1171 }
1172 } else {
1173 retval = down_timeout(&file_data->limit_write_sem,
1174 expire);
1175 if (retval < 0) {
1176 retval = -ETIMEDOUT;
1177 goto error;
1178 }
1179 }
1180
1181 spin_lock_irq(&file_data->err_lock);
1182 retval = file_data->out_status;
1183 spin_unlock_irq(&file_data->err_lock);
1184 if (retval < 0) {
1185 up(&file_data->limit_write_sem);
1186 goto error;
1187 }
1188
1189 /* prepare next urb to send */
1190 urb = usbtmc_create_urb();
1191 if (!urb) {
1192 retval = -ENOMEM;
1193 up(&file_data->limit_write_sem);
1194 goto error;
1195 }
1196 buffer = urb->transfer_buffer;
1197
1198 if (remaining > bufsize)
1199 this_part = bufsize;
1200 else
1201 this_part = remaining;
1202
1203 if (copy_from_user(buffer, user_buffer + done, this_part)) {
1204 retval = -EFAULT;
1205 up(&file_data->limit_write_sem);
1206 goto error;
1207 }
1208
1209 print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE,
1210 16, 1, buffer, this_part, true);
1211
1212 /* fill bulk with 32 bit alignment to meet USBTMC specification
1213 * (size + 3 & ~3) rounds up and simplifies user code
1214 */
1215 aligned = (this_part + 3) & ~3;
1216 dev_dbg(dev, "write(size:%u align:%u done:%u)\n",
1217 (unsigned int)this_part,
1218 (unsigned int)aligned,
1219 (unsigned int)done);
1220
1221 usb_fill_bulk_urb(urb, data->usb_dev,
1222 usb_sndbulkpipe(data->usb_dev, data->bulk_out),
1223 urb->transfer_buffer, aligned,
1224 usbtmc_write_bulk_cb, file_data);
1225
1226 usb_anchor_urb(urb, &file_data->submitted);
1227 retval = usb_submit_urb(urb, GFP_KERNEL);
1228 if (unlikely(retval)) {
1229 usb_unanchor_urb(urb);
1230 up(&file_data->limit_write_sem);
1231 goto error;
1232 }
1233
1234 usb_free_urb(urb);
1235 urb = NULL; /* urb will be finally released by usb driver */
1236
1237 remaining -= this_part;
1238 done += this_part;
1239 }
1240
1241 /* All urbs are on the fly */
1242 if (!(flags & USBTMC_FLAG_ASYNC)) {
1243 if (!usb_wait_anchor_empty_timeout(&file_data->submitted,
1244 timeout)) {
1245 retval = -ETIMEDOUT;
1246 goto error;
1247 }
1248 }
1249
1250 retval = 0;
1251 goto exit;
1252
1253error:
1254 usb_kill_anchored_urbs(&file_data->submitted);
1255exit:
1256 usb_free_urb(urb);
1257
1258 spin_lock_irq(&file_data->err_lock);
1259 if (!(flags & USBTMC_FLAG_ASYNC))
1260 done = file_data->out_transfer_size;
1261 if (!retval && file_data->out_status)
1262 retval = file_data->out_status;
1263 spin_unlock_irq(&file_data->err_lock);
1264
1265 *transferred = done;
1266
1267 dev_dbg(dev, "%s: done=%u, retval=%d, urbstat=%d\n",
1268 __func__, done, retval, file_data->out_status);
1269
1270 return retval;
1271}
1272
1273static ssize_t usbtmc_ioctl_generic_write(struct usbtmc_file_data *file_data,
1274 void __user *arg)
1275{
1276 struct usbtmc_message msg;
1277 ssize_t retval = 0;
1278
1279 /* mutex already locked */
1280
1281 if (copy_from_user(&msg, arg, sizeof(struct usbtmc_message)))
1282 return -EFAULT;
1283
1284 retval = usbtmc_generic_write(file_data, msg.message,
1285 msg.transfer_size, &msg.transferred,
1286 msg.flags);
1287
1288 if (put_user(msg.transferred,
1289 &((struct usbtmc_message __user *)arg)->transferred))
1290 return -EFAULT;
1291
1292 return retval;
1293}
1294
1295/*
1296 * Get the generic write result
1297 */
1298static ssize_t usbtmc_ioctl_write_result(struct usbtmc_file_data *file_data,
1299 void __user *arg)
1300{
1301 u32 transferred;
1302 int retval;
1303
1304 spin_lock_irq(&file_data->err_lock);
1305 transferred = file_data->out_transfer_size;
1306 retval = file_data->out_status;
1307 spin_unlock_irq(&file_data->err_lock);
1308
1309 if (put_user(transferred, (__u32 __user *)arg))
1310 return -EFAULT;
1311
1312 return retval;
1313}
1314
1315/*
1316 * Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-OUT endpoint.
1317 * @transfer_size: number of bytes to request from the device.
1318 *
1319 * See the USBTMC specification, Table 4.
1320 *
1321 * Also updates bTag_last_write.
1322 */
1323static int send_request_dev_dep_msg_in(struct usbtmc_file_data *file_data,
1324 u32 transfer_size)
1325{
1326 struct usbtmc_device_data *data = file_data->data;
1327 int retval;
1328 u8 *buffer;
1329 int actual;
1330
1331 buffer = kmalloc(USBTMC_HEADER_SIZE, GFP_KERNEL);
1332 if (!buffer)
1333 return -ENOMEM;
1334 /* Setup IO buffer for REQUEST_DEV_DEP_MSG_IN message
1335 * Refer to class specs for details
1336 */
1337 buffer[0] = 2;
1338 buffer[1] = data->bTag;
1339 buffer[2] = ~data->bTag;
1340 buffer[3] = 0; /* Reserved */
1341 buffer[4] = transfer_size >> 0;
1342 buffer[5] = transfer_size >> 8;
1343 buffer[6] = transfer_size >> 16;
1344 buffer[7] = transfer_size >> 24;
1345 buffer[8] = file_data->term_char_enabled * 2;
1346 /* Use term character? */
1347 buffer[9] = file_data->term_char;
1348 buffer[10] = 0; /* Reserved */
1349 buffer[11] = 0; /* Reserved */
1350
1351 /* Send bulk URB */
1352 retval = usb_bulk_msg_killable(data->usb_dev,
1353 usb_sndbulkpipe(data->usb_dev,
1354 data->bulk_out),
1355 buffer, USBTMC_HEADER_SIZE,
1356 &actual, file_data->timeout);
1357
1358 /* Store bTag (in case we need to abort) */
1359 data->bTag_last_write = data->bTag;
1360
1361 /* Increment bTag -- and increment again if zero */
1362 data->bTag++;
1363 if (!data->bTag)
1364 data->bTag++;
1365
1366 kfree(buffer);
1367 if (retval < 0)
1368 dev_err(&data->intf->dev, "%s returned %d\n",
1369 __func__, retval);
1370
1371 return retval;
1372}
1373
1374static ssize_t usbtmc_read(struct file *filp, char __user *buf,
1375 size_t count, loff_t *f_pos)
1376{
1377 struct usbtmc_file_data *file_data;
1378 struct usbtmc_device_data *data;
1379 struct device *dev;
1380 const u32 bufsize = USBTMC_BUFSIZE;
1381 u32 n_characters;
1382 u8 *buffer;
1383 int actual;
1384 u32 done = 0;
1385 u32 remaining;
1386 int retval;
1387
1388 /* Get pointer to private data structure */
1389 file_data = filp->private_data;
1390 data = file_data->data;
1391 dev = &data->intf->dev;
1392
1393 buffer = kmalloc(bufsize, GFP_KERNEL);
1394 if (!buffer)
1395 return -ENOMEM;
1396
1397 retval = mutex_lock_interruptible(&data->io_mutex);
1398 if (retval < 0)
1399 goto exit_nolock;
1400
1401 if (data->zombie) {
1402 retval = -ENODEV;
1403 goto exit;
1404 }
1405
1406 if (count > INT_MAX)
1407 count = INT_MAX;
1408
1409 dev_dbg(dev, "%s(count:%zu)\n", __func__, count);
1410
1411 retval = send_request_dev_dep_msg_in(file_data, count);
1412
1413 if (retval < 0) {
1414 if (file_data->auto_abort)
1415 usbtmc_ioctl_abort_bulk_out(data);
1416 goto exit;
1417 }
1418
1419 /* Loop until we have fetched everything we requested */
1420 remaining = count;
1421 actual = 0;
1422
1423 /* Send bulk URB */
1424 retval = usb_bulk_msg_killable(data->usb_dev,
1425 usb_rcvbulkpipe(data->usb_dev,
1426 data->bulk_in),
1427 buffer, bufsize, &actual,
1428 file_data->timeout);
1429
1430 dev_dbg(dev, "%s: bulk_msg retval(%u), actual(%d)\n",
1431 __func__, retval, actual);
1432
1433 /* Store bTag (in case we need to abort) */
1434 data->bTag_last_read = data->bTag;
1435
1436 if (retval < 0) {
1437 if (file_data->auto_abort)
1438 usbtmc_ioctl_abort_bulk_in(data);
1439 goto exit;
1440 }
1441
1442 /* Sanity checks for the header */
1443 if (actual < USBTMC_HEADER_SIZE) {
1444 dev_err(dev, "Device sent too small first packet: %u < %u\n",
1445 actual, USBTMC_HEADER_SIZE);
1446 if (file_data->auto_abort)
1447 usbtmc_ioctl_abort_bulk_in(data);
1448 goto exit;
1449 }
1450
1451 if (buffer[0] != 2) {
1452 dev_err(dev, "Device sent reply with wrong MsgID: %u != 2\n",
1453 buffer[0]);
1454 if (file_data->auto_abort)
1455 usbtmc_ioctl_abort_bulk_in(data);
1456 goto exit;
1457 }
1458
1459 if (buffer[1] != data->bTag_last_write) {
1460 dev_err(dev, "Device sent reply with wrong bTag: %u != %u\n",
1461 buffer[1], data->bTag_last_write);
1462 if (file_data->auto_abort)
1463 usbtmc_ioctl_abort_bulk_in(data);
1464 goto exit;
1465 }
1466
1467 /* How many characters did the instrument send? */
1468 n_characters = buffer[4] +
1469 (buffer[5] << 8) +
1470 (buffer[6] << 16) +
1471 (buffer[7] << 24);
1472
1473 file_data->bmTransferAttributes = buffer[8];
1474
1475 dev_dbg(dev, "Bulk-IN header: N_characters(%u), bTransAttr(%u)\n",
1476 n_characters, buffer[8]);
1477
1478 if (n_characters > remaining) {
1479 dev_err(dev, "Device wants to return more data than requested: %u > %zu\n",
1480 n_characters, count);
1481 if (file_data->auto_abort)
1482 usbtmc_ioctl_abort_bulk_in(data);
1483 goto exit;
1484 }
1485
1486 print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE,
1487 16, 1, buffer, actual, true);
1488
1489 remaining = n_characters;
1490
1491 /* Remove the USBTMC header */
1492 actual -= USBTMC_HEADER_SIZE;
1493
1494 /* Remove padding if it exists */
1495 if (actual > remaining)
1496 actual = remaining;
1497
1498 remaining -= actual;
1499
1500 /* Copy buffer to user space */
1501 if (copy_to_user(buf, &buffer[USBTMC_HEADER_SIZE], actual)) {
1502 /* There must have been an addressing problem */
1503 retval = -EFAULT;
1504 goto exit;
1505 }
1506
1507 if ((actual + USBTMC_HEADER_SIZE) == bufsize) {
1508 retval = usbtmc_generic_read(file_data, buf + actual,
1509 remaining,
1510 &done,
1511 USBTMC_FLAG_IGNORE_TRAILER);
1512 if (retval < 0)
1513 goto exit;
1514 }
1515 done += actual;
1516
1517 /* Update file position value */
1518 *f_pos = *f_pos + done;
1519 retval = done;
1520
1521exit:
1522 mutex_unlock(&data->io_mutex);
1523exit_nolock:
1524 kfree(buffer);
1525 return retval;
1526}
1527
1528static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
1529 size_t count, loff_t *f_pos)
1530{
1531 struct usbtmc_file_data *file_data;
1532 struct usbtmc_device_data *data;
1533 struct urb *urb = NULL;
1534 ssize_t retval = 0;
1535 u8 *buffer;
1536 u32 remaining, done;
1537 u32 transfersize, aligned, buflen;
1538
1539 file_data = filp->private_data;
1540 data = file_data->data;
1541
1542 mutex_lock(&data->io_mutex);
1543
1544 if (data->zombie) {
1545 retval = -ENODEV;
1546 goto exit;
1547 }
1548
1549 done = 0;
1550
1551 spin_lock_irq(&file_data->err_lock);
1552 file_data->out_transfer_size = 0;
1553 file_data->out_status = 0;
1554 spin_unlock_irq(&file_data->err_lock);
1555
1556 if (!count)
1557 goto exit;
1558
1559 if (down_trylock(&file_data->limit_write_sem)) {
1560 /* previous calls were async */
1561 retval = -EBUSY;
1562 goto exit;
1563 }
1564
1565 urb = usbtmc_create_urb();
1566 if (!urb) {
1567 retval = -ENOMEM;
1568 up(&file_data->limit_write_sem);
1569 goto exit;
1570 }
1571
1572 buffer = urb->transfer_buffer;
1573 buflen = urb->transfer_buffer_length;
1574
1575 if (count > INT_MAX) {
1576 transfersize = INT_MAX;
1577 buffer[8] = 0;
1578 } else {
1579 transfersize = count;
1580 buffer[8] = file_data->eom_val;
1581 }
1582
1583 /* Setup IO buffer for DEV_DEP_MSG_OUT message */
1584 buffer[0] = 1;
1585 buffer[1] = data->bTag;
1586 buffer[2] = ~data->bTag;
1587 buffer[3] = 0; /* Reserved */
1588 buffer[4] = transfersize >> 0;
1589 buffer[5] = transfersize >> 8;
1590 buffer[6] = transfersize >> 16;
1591 buffer[7] = transfersize >> 24;
1592 /* buffer[8] is set above... */
1593 buffer[9] = 0; /* Reserved */
1594 buffer[10] = 0; /* Reserved */
1595 buffer[11] = 0; /* Reserved */
1596
1597 remaining = transfersize;
1598
1599 if (transfersize + USBTMC_HEADER_SIZE > buflen) {
1600 transfersize = buflen - USBTMC_HEADER_SIZE;
1601 aligned = buflen;
1602 } else {
1603 aligned = (transfersize + (USBTMC_HEADER_SIZE + 3)) & ~3;
1604 }
1605
1606 if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf, transfersize)) {
1607 retval = -EFAULT;
1608 up(&file_data->limit_write_sem);
1609 goto exit;
1610 }
1611
1612 dev_dbg(&data->intf->dev, "%s(size:%u align:%u)\n", __func__,
1613 (unsigned int)transfersize, (unsigned int)aligned);
1614
1615 print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE,
1616 16, 1, buffer, aligned, true);
1617
1618 usb_fill_bulk_urb(urb, data->usb_dev,
1619 usb_sndbulkpipe(data->usb_dev, data->bulk_out),
1620 urb->transfer_buffer, aligned,
1621 usbtmc_write_bulk_cb, file_data);
1622
1623 usb_anchor_urb(urb, &file_data->submitted);
1624 retval = usb_submit_urb(urb, GFP_KERNEL);
1625 if (unlikely(retval)) {
1626 usb_unanchor_urb(urb);
1627 up(&file_data->limit_write_sem);
1628 goto exit;
1629 }
1630
1631 remaining -= transfersize;
1632
1633 data->bTag_last_write = data->bTag;
1634 data->bTag++;
1635
1636 if (!data->bTag)
1637 data->bTag++;
1638
1639 /* call generic_write even when remaining = 0 */
1640 retval = usbtmc_generic_write(file_data, buf + transfersize, remaining,
1641 &done, USBTMC_FLAG_APPEND);
1642 /* truncate alignment bytes */
1643 if (done > remaining)
1644 done = remaining;
1645
1646 /*add size of first urb*/
1647 done += transfersize;
1648
1649 if (retval < 0) {
1650 usb_kill_anchored_urbs(&file_data->submitted);
1651
1652 dev_err(&data->intf->dev,
1653 "Unable to send data, error %d\n", (int)retval);
1654 if (file_data->auto_abort)
1655 usbtmc_ioctl_abort_bulk_out(data);
1656 goto exit;
1657 }
1658
1659 retval = done;
1660exit:
1661 usb_free_urb(urb);
1662 mutex_unlock(&data->io_mutex);
1663 return retval;
1664}
1665
1666static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
1667{
1668 struct device *dev;
1669 u8 *buffer;
1670 int rv;
1671 int n;
1672 int actual = 0;
1673
1674 dev = &data->intf->dev;
1675
1676 dev_dbg(dev, "Sending INITIATE_CLEAR request\n");
1677
1678 buffer = kmalloc(USBTMC_BUFSIZE, GFP_KERNEL);
1679 if (!buffer)
1680 return -ENOMEM;
1681
1682 rv = usb_control_msg(data->usb_dev,
1683 usb_rcvctrlpipe(data->usb_dev, 0),
1684 USBTMC_REQUEST_INITIATE_CLEAR,
1685 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1686 0, 0, buffer, 1, USB_CTRL_GET_TIMEOUT);
1687 if (rv < 0) {
1688 dev_err(dev, "usb_control_msg returned %d\n", rv);
1689 goto exit;
1690 }
1691
1692 dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
1693
1694 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1695 dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
1696 rv = -EPERM;
1697 goto exit;
1698 }
1699
1700 n = 0;
1701
1702usbtmc_clear_check_status:
1703
1704 dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n");
1705
1706 rv = usb_control_msg(data->usb_dev,
1707 usb_rcvctrlpipe(data->usb_dev, 0),
1708 USBTMC_REQUEST_CHECK_CLEAR_STATUS,
1709 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1710 0, 0, buffer, 2, USB_CTRL_GET_TIMEOUT);
1711 if (rv < 0) {
1712 dev_err(dev, "usb_control_msg returned %d\n", rv);
1713 goto exit;
1714 }
1715
1716 dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
1717
1718 if (buffer[0] == USBTMC_STATUS_SUCCESS)
1719 goto usbtmc_clear_bulk_out_halt;
1720
1721 if (buffer[0] != USBTMC_STATUS_PENDING) {
1722 dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
1723 rv = -EPERM;
1724 goto exit;
1725 }
1726
1727 if ((buffer[1] & 1) != 0) {
1728 do {
1729 dev_dbg(dev, "Reading from bulk in EP\n");
1730
1731 actual = 0;
1732 rv = usb_bulk_msg(data->usb_dev,
1733 usb_rcvbulkpipe(data->usb_dev,
1734 data->bulk_in),
1735 buffer, USBTMC_BUFSIZE,
1736 &actual, USB_CTRL_GET_TIMEOUT);
1737
1738 print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE,
1739 16, 1, buffer, actual, true);
1740
1741 n++;
1742
1743 if (rv < 0) {
1744 dev_err(dev, "usb_control_msg returned %d\n",
1745 rv);
1746 goto exit;
1747 }
1748 } while ((actual == USBTMC_BUFSIZE) &&
1749 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
1750 } else {
1751 /* do not stress device with subsequent requests */
1752 msleep(50);
1753 n++;
1754 }
1755
1756 if (n >= USBTMC_MAX_READS_TO_CLEAR_BULK_IN) {
1757 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
1758 USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
1759 rv = -EPERM;
1760 goto exit;
1761 }
1762
1763 goto usbtmc_clear_check_status;
1764
1765usbtmc_clear_bulk_out_halt:
1766
1767 rv = usb_clear_halt(data->usb_dev,
1768 usb_sndbulkpipe(data->usb_dev, data->bulk_out));
1769 if (rv < 0) {
1770 dev_err(dev, "usb_clear_halt returned %d\n", rv);
1771 goto exit;
1772 }
1773 rv = 0;
1774
1775exit:
1776 kfree(buffer);
1777 return rv;
1778}
1779
1780static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
1781{
1782 int rv;
1783
1784 rv = usb_clear_halt(data->usb_dev,
1785 usb_sndbulkpipe(data->usb_dev, data->bulk_out));
1786
1787 if (rv < 0)
1788 dev_err(&data->usb_dev->dev, "%s returned %d\n", __func__, rv);
1789 return rv;
1790}
1791
1792static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
1793{
1794 int rv;
1795
1796 rv = usb_clear_halt(data->usb_dev,
1797 usb_rcvbulkpipe(data->usb_dev, data->bulk_in));
1798
1799 if (rv < 0)
1800 dev_err(&data->usb_dev->dev, "%s returned %d\n", __func__, rv);
1801 return rv;
1802}
1803
1804static int usbtmc_ioctl_cancel_io(struct usbtmc_file_data *file_data)
1805{
1806 spin_lock_irq(&file_data->err_lock);
1807 file_data->in_status = -ECANCELED;
1808 file_data->out_status = -ECANCELED;
1809 spin_unlock_irq(&file_data->err_lock);
1810 usb_kill_anchored_urbs(&file_data->submitted);
1811 return 0;
1812}
1813
1814static int usbtmc_ioctl_cleanup_io(struct usbtmc_file_data *file_data)
1815{
1816 usb_kill_anchored_urbs(&file_data->submitted);
1817 usb_scuttle_anchored_urbs(&file_data->in_anchor);
1818 spin_lock_irq(&file_data->err_lock);
1819 file_data->in_status = 0;
1820 file_data->in_transfer_size = 0;
1821 file_data->out_status = 0;
1822 file_data->out_transfer_size = 0;
1823 spin_unlock_irq(&file_data->err_lock);
1824
1825 file_data->in_urbs_used = 0;
1826 return 0;
1827}
1828
1829static int get_capabilities(struct usbtmc_device_data *data)
1830{
1831 struct device *dev = &data->usb_dev->dev;
1832 char *buffer;
1833 int rv = 0;
1834
1835 buffer = kmalloc(0x18, GFP_KERNEL);
1836 if (!buffer)
1837 return -ENOMEM;
1838
1839 rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0),
1840 USBTMC_REQUEST_GET_CAPABILITIES,
1841 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1842 0, 0, buffer, 0x18, USB_CTRL_GET_TIMEOUT);
1843 if (rv < 0) {
1844 dev_err(dev, "usb_control_msg returned %d\n", rv);
1845 goto err_out;
1846 }
1847
1848 dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
1849 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1850 dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
1851 rv = -EPERM;
1852 goto err_out;
1853 }
1854 dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
1855 dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
1856 dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
1857 dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
1858
1859 data->capabilities.interface_capabilities = buffer[4];
1860 data->capabilities.device_capabilities = buffer[5];
1861 data->capabilities.usb488_interface_capabilities = buffer[14];
1862 data->capabilities.usb488_device_capabilities = buffer[15];
1863 data->usb488_caps = (buffer[14] & 0x07) | ((buffer[15] & 0x0f) << 4);
1864 rv = 0;
1865
1866err_out:
1867 kfree(buffer);
1868 return rv;
1869}
1870
1871#define capability_attribute(name) \
1872static ssize_t name##_show(struct device *dev, \
1873 struct device_attribute *attr, char *buf) \
1874{ \
1875 struct usb_interface *intf = to_usb_interface(dev); \
1876 struct usbtmc_device_data *data = usb_get_intfdata(intf); \
1877 \
1878 return sprintf(buf, "%d\n", data->capabilities.name); \
1879} \
1880static DEVICE_ATTR_RO(name)
1881
1882capability_attribute(interface_capabilities);
1883capability_attribute(device_capabilities);
1884capability_attribute(usb488_interface_capabilities);
1885capability_attribute(usb488_device_capabilities);
1886
1887static struct attribute *usbtmc_attrs[] = {
1888 &dev_attr_interface_capabilities.attr,
1889 &dev_attr_device_capabilities.attr,
1890 &dev_attr_usb488_interface_capabilities.attr,
1891 &dev_attr_usb488_device_capabilities.attr,
1892 NULL,
1893};
1894ATTRIBUTE_GROUPS(usbtmc);
1895
1896static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data)
1897{
1898 struct device *dev;
1899 u8 *buffer;
1900 int rv;
1901
1902 dev = &data->intf->dev;
1903
1904 buffer = kmalloc(2, GFP_KERNEL);
1905 if (!buffer)
1906 return -ENOMEM;
1907
1908 rv = usb_control_msg(data->usb_dev,
1909 usb_rcvctrlpipe(data->usb_dev, 0),
1910 USBTMC_REQUEST_INDICATOR_PULSE,
1911 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1912 0, 0, buffer, 0x01, USB_CTRL_GET_TIMEOUT);
1913
1914 if (rv < 0) {
1915 dev_err(dev, "usb_control_msg returned %d\n", rv);
1916 goto exit;
1917 }
1918
1919 dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
1920
1921 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1922 dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
1923 rv = -EPERM;
1924 goto exit;
1925 }
1926 rv = 0;
1927
1928exit:
1929 kfree(buffer);
1930 return rv;
1931}
1932
1933static int usbtmc_ioctl_request(struct usbtmc_device_data *data,
1934 void __user *arg)
1935{
1936 struct device *dev = &data->intf->dev;
1937 struct usbtmc_ctrlrequest request;
1938 u8 *buffer = NULL;
1939 int rv;
1940 unsigned int is_in, pipe;
1941
1942 if (copy_from_user(&request, arg, sizeof(struct usbtmc_ctrlrequest)))
1943 return -EFAULT;
1944
1945 if (request.req.wLength > USBTMC_BUFSIZE)
1946 return -EMSGSIZE;
1947 if (request.req.wLength == 0) /* Length-0 requests are never IN */
1948 request.req.bRequestType &= ~USB_DIR_IN;
1949
1950 is_in = request.req.bRequestType & USB_DIR_IN;
1951
1952 if (request.req.wLength) {
1953 buffer = kmalloc(request.req.wLength, GFP_KERNEL);
1954 if (!buffer)
1955 return -ENOMEM;
1956
1957 if (!is_in) {
1958 /* Send control data to device */
1959 if (copy_from_user(buffer, request.data,
1960 request.req.wLength)) {
1961 rv = -EFAULT;
1962 goto exit;
1963 }
1964 }
1965 }
1966
1967 if (is_in)
1968 pipe = usb_rcvctrlpipe(data->usb_dev, 0);
1969 else
1970 pipe = usb_sndctrlpipe(data->usb_dev, 0);
1971 rv = usb_control_msg(data->usb_dev,
1972 pipe,
1973 request.req.bRequest,
1974 request.req.bRequestType,
1975 request.req.wValue,
1976 request.req.wIndex,
1977 buffer, request.req.wLength, USB_CTRL_GET_TIMEOUT);
1978
1979 if (rv < 0) {
1980 dev_err(dev, "%s failed %d\n", __func__, rv);
1981 goto exit;
1982 }
1983
1984 if (rv && is_in) {
1985 /* Read control data from device */
1986 if (copy_to_user(request.data, buffer, rv))
1987 rv = -EFAULT;
1988 }
1989
1990 exit:
1991 kfree(buffer);
1992 return rv;
1993}
1994
1995/*
1996 * Get the usb timeout value
1997 */
1998static int usbtmc_ioctl_get_timeout(struct usbtmc_file_data *file_data,
1999 void __user *arg)
2000{
2001 u32 timeout;
2002
2003 timeout = file_data->timeout;
2004
2005 return put_user(timeout, (__u32 __user *)arg);
2006}
2007
2008/*
2009 * Set the usb timeout value
2010 */
2011static int usbtmc_ioctl_set_timeout(struct usbtmc_file_data *file_data,
2012 void __user *arg)
2013{
2014 u32 timeout;
2015
2016 if (get_user(timeout, (__u32 __user *)arg))
2017 return -EFAULT;
2018
2019 /* Note that timeout = 0 means
2020 * MAX_SCHEDULE_TIMEOUT in usb_control_msg
2021 */
2022 if (timeout < USBTMC_MIN_TIMEOUT)
2023 return -EINVAL;
2024
2025 file_data->timeout = timeout;
2026
2027 return 0;
2028}
2029
2030/*
2031 * enables/disables sending EOM on write
2032 */
2033static int usbtmc_ioctl_eom_enable(struct usbtmc_file_data *file_data,
2034 void __user *arg)
2035{
2036 u8 eom_enable;
2037
2038 if (copy_from_user(&eom_enable, arg, sizeof(eom_enable)))
2039 return -EFAULT;
2040
2041 if (eom_enable > 1)
2042 return -EINVAL;
2043
2044 file_data->eom_val = eom_enable;
2045
2046 return 0;
2047}
2048
2049/*
2050 * Configure termination character for read()
2051 */
2052static int usbtmc_ioctl_config_termc(struct usbtmc_file_data *file_data,
2053 void __user *arg)
2054{
2055 struct usbtmc_termchar termc;
2056
2057 if (copy_from_user(&termc, arg, sizeof(termc)))
2058 return -EFAULT;
2059
2060 if ((termc.term_char_enabled > 1) ||
2061 (termc.term_char_enabled &&
2062 !(file_data->data->capabilities.device_capabilities & 1)))
2063 return -EINVAL;
2064
2065 file_data->term_char = termc.term_char;
2066 file_data->term_char_enabled = termc.term_char_enabled;
2067
2068 return 0;
2069}
2070
2071static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2072{
2073 struct usbtmc_file_data *file_data;
2074 struct usbtmc_device_data *data;
2075 int retval = -EBADRQC;
2076 __u8 tmp_byte;
2077
2078 file_data = file->private_data;
2079 data = file_data->data;
2080
2081 mutex_lock(&data->io_mutex);
2082 if (data->zombie) {
2083 retval = -ENODEV;
2084 goto skip_io_on_zombie;
2085 }
2086
2087 switch (cmd) {
2088 case USBTMC_IOCTL_CLEAR_OUT_HALT:
2089 retval = usbtmc_ioctl_clear_out_halt(data);
2090 break;
2091
2092 case USBTMC_IOCTL_CLEAR_IN_HALT:
2093 retval = usbtmc_ioctl_clear_in_halt(data);
2094 break;
2095
2096 case USBTMC_IOCTL_INDICATOR_PULSE:
2097 retval = usbtmc_ioctl_indicator_pulse(data);
2098 break;
2099
2100 case USBTMC_IOCTL_CLEAR:
2101 retval = usbtmc_ioctl_clear(data);
2102 break;
2103
2104 case USBTMC_IOCTL_ABORT_BULK_OUT:
2105 retval = usbtmc_ioctl_abort_bulk_out(data);
2106 break;
2107
2108 case USBTMC_IOCTL_ABORT_BULK_IN:
2109 retval = usbtmc_ioctl_abort_bulk_in(data);
2110 break;
2111
2112 case USBTMC_IOCTL_CTRL_REQUEST:
2113 retval = usbtmc_ioctl_request(data, (void __user *)arg);
2114 break;
2115
2116 case USBTMC_IOCTL_GET_TIMEOUT:
2117 retval = usbtmc_ioctl_get_timeout(file_data,
2118 (void __user *)arg);
2119 break;
2120
2121 case USBTMC_IOCTL_SET_TIMEOUT:
2122 retval = usbtmc_ioctl_set_timeout(file_data,
2123 (void __user *)arg);
2124 break;
2125
2126 case USBTMC_IOCTL_EOM_ENABLE:
2127 retval = usbtmc_ioctl_eom_enable(file_data,
2128 (void __user *)arg);
2129 break;
2130
2131 case USBTMC_IOCTL_CONFIG_TERMCHAR:
2132 retval = usbtmc_ioctl_config_termc(file_data,
2133 (void __user *)arg);
2134 break;
2135
2136 case USBTMC_IOCTL_WRITE:
2137 retval = usbtmc_ioctl_generic_write(file_data,
2138 (void __user *)arg);
2139 break;
2140
2141 case USBTMC_IOCTL_READ:
2142 retval = usbtmc_ioctl_generic_read(file_data,
2143 (void __user *)arg);
2144 break;
2145
2146 case USBTMC_IOCTL_WRITE_RESULT:
2147 retval = usbtmc_ioctl_write_result(file_data,
2148 (void __user *)arg);
2149 break;
2150
2151 case USBTMC_IOCTL_API_VERSION:
2152 retval = put_user(USBTMC_API_VERSION,
2153 (__u32 __user *)arg);
2154 break;
2155
2156 case USBTMC488_IOCTL_GET_CAPS:
2157 retval = put_user(data->usb488_caps,
2158 (unsigned char __user *)arg);
2159 break;
2160
2161 case USBTMC488_IOCTL_READ_STB:
2162 retval = usbtmc488_ioctl_read_stb(file_data,
2163 (void __user *)arg);
2164 break;
2165
2166 case USBTMC488_IOCTL_REN_CONTROL:
2167 retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
2168 USBTMC488_REQUEST_REN_CONTROL);
2169 break;
2170
2171 case USBTMC488_IOCTL_GOTO_LOCAL:
2172 retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
2173 USBTMC488_REQUEST_GOTO_LOCAL);
2174 break;
2175
2176 case USBTMC488_IOCTL_LOCAL_LOCKOUT:
2177 retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
2178 USBTMC488_REQUEST_LOCAL_LOCKOUT);
2179 break;
2180
2181 case USBTMC488_IOCTL_TRIGGER:
2182 retval = usbtmc488_ioctl_trigger(file_data);
2183 break;
2184
2185 case USBTMC488_IOCTL_WAIT_SRQ:
2186 retval = usbtmc488_ioctl_wait_srq(file_data,
2187 (__u32 __user *)arg);
2188 break;
2189
2190 case USBTMC_IOCTL_MSG_IN_ATTR:
2191 retval = put_user(file_data->bmTransferAttributes,
2192 (__u8 __user *)arg);
2193 break;
2194
2195 case USBTMC_IOCTL_AUTO_ABORT:
2196 retval = get_user(tmp_byte, (unsigned char __user *)arg);
2197 if (retval == 0)
2198 file_data->auto_abort = !!tmp_byte;
2199 break;
2200
2201 case USBTMC_IOCTL_GET_STB:
2202 retval = usbtmc_get_stb(file_data, &tmp_byte);
2203 if (!retval)
2204 retval = put_user(tmp_byte, (__u8 __user *)arg);
2205 break;
2206
2207 case USBTMC_IOCTL_GET_SRQ_STB:
2208 retval = usbtmc_ioctl_get_srq_stb(file_data,
2209 (void __user *)arg);
2210 break;
2211
2212 case USBTMC_IOCTL_CANCEL_IO:
2213 retval = usbtmc_ioctl_cancel_io(file_data);
2214 break;
2215
2216 case USBTMC_IOCTL_CLEANUP_IO:
2217 retval = usbtmc_ioctl_cleanup_io(file_data);
2218 break;
2219 }
2220
2221skip_io_on_zombie:
2222 mutex_unlock(&data->io_mutex);
2223 return retval;
2224}
2225
2226static int usbtmc_fasync(int fd, struct file *file, int on)
2227{
2228 struct usbtmc_file_data *file_data = file->private_data;
2229
2230 return fasync_helper(fd, file, on, &file_data->data->fasync);
2231}
2232
2233static __poll_t usbtmc_poll(struct file *file, poll_table *wait)
2234{
2235 struct usbtmc_file_data *file_data = file->private_data;
2236 struct usbtmc_device_data *data = file_data->data;
2237 __poll_t mask;
2238
2239 mutex_lock(&data->io_mutex);
2240
2241 if (data->zombie) {
2242 mask = EPOLLHUP | EPOLLERR;
2243 goto no_poll;
2244 }
2245
2246 poll_wait(file, &data->waitq, wait);
2247
2248 /* Note that EPOLLPRI is now assigned to SRQ, and
2249 * EPOLLIN|EPOLLRDNORM to normal read data.
2250 */
2251 mask = 0;
2252 if (atomic_read(&file_data->srq_asserted))
2253 mask |= EPOLLPRI;
2254
2255 /* Note that the anchor submitted includes all urbs for BULK IN
2256 * and OUT. So EPOLLOUT is signaled when BULK OUT is empty and
2257 * all BULK IN urbs are completed and moved to in_anchor.
2258 */
2259 if (usb_anchor_empty(&file_data->submitted))
2260 mask |= (EPOLLOUT | EPOLLWRNORM);
2261 if (!usb_anchor_empty(&file_data->in_anchor))
2262 mask |= (EPOLLIN | EPOLLRDNORM);
2263
2264 spin_lock_irq(&file_data->err_lock);
2265 if (file_data->in_status || file_data->out_status)
2266 mask |= EPOLLERR;
2267 spin_unlock_irq(&file_data->err_lock);
2268
2269 dev_dbg(&data->intf->dev, "poll mask = %x\n", mask);
2270
2271no_poll:
2272 mutex_unlock(&data->io_mutex);
2273 return mask;
2274}
2275
2276static const struct file_operations fops = {
2277 .owner = THIS_MODULE,
2278 .read = usbtmc_read,
2279 .write = usbtmc_write,
2280 .open = usbtmc_open,
2281 .release = usbtmc_release,
2282 .flush = usbtmc_flush,
2283 .unlocked_ioctl = usbtmc_ioctl,
2284 .compat_ioctl = compat_ptr_ioctl,
2285 .fasync = usbtmc_fasync,
2286 .poll = usbtmc_poll,
2287 .llseek = default_llseek,
2288};
2289
2290static struct usb_class_driver usbtmc_class = {
2291 .name = "usbtmc%d",
2292 .fops = &fops,
2293 .minor_base = USBTMC_MINOR_BASE,
2294};
2295
2296static void usbtmc_interrupt(struct urb *urb)
2297{
2298 struct usbtmc_device_data *data = urb->context;
2299 struct device *dev = &data->intf->dev;
2300 int status = urb->status;
2301 int rv;
2302
2303 dev_dbg(&data->intf->dev, "int status: %d len %d\n",
2304 status, urb->actual_length);
2305
2306 switch (status) {
2307 case 0: /* SUCCESS */
2308 /* ensure at least two bytes of headers were transferred */
2309 if (urb->actual_length < 2) {
2310 dev_warn(dev,
2311 "actual length %d not sufficient for interrupt headers\n",
2312 urb->actual_length);
2313 goto exit;
2314 }
2315
2316 /* check for valid STB notification */
2317 if (data->iin_buffer[0] > 0x81) {
2318 data->bNotify1 = data->iin_buffer[0];
2319 data->bNotify2 = data->iin_buffer[1];
2320 atomic_set(&data->iin_data_valid, 1);
2321 wake_up_interruptible(&data->waitq);
2322 goto exit;
2323 }
2324 /* check for SRQ notification */
2325 if (data->iin_buffer[0] == 0x81) {
2326 unsigned long flags;
2327 struct list_head *elem;
2328
2329 if (data->fasync)
2330 kill_fasync(&data->fasync,
2331 SIGIO, POLL_PRI);
2332
2333 spin_lock_irqsave(&data->dev_lock, flags);
2334 list_for_each(elem, &data->file_list) {
2335 struct usbtmc_file_data *file_data;
2336
2337 file_data = list_entry(elem,
2338 struct usbtmc_file_data,
2339 file_elem);
2340 file_data->srq_byte = data->iin_buffer[1];
2341 atomic_set(&file_data->srq_asserted, 1);
2342 }
2343 spin_unlock_irqrestore(&data->dev_lock, flags);
2344
2345 dev_dbg(dev, "srq received bTag %x stb %x\n",
2346 (unsigned int)data->iin_buffer[0],
2347 (unsigned int)data->iin_buffer[1]);
2348 wake_up_interruptible_all(&data->waitq);
2349 goto exit;
2350 }
2351 dev_warn(dev, "invalid notification: %x\n",
2352 data->iin_buffer[0]);
2353 break;
2354 case -EOVERFLOW:
2355 dev_err(dev, "overflow with length %d, actual length is %d\n",
2356 data->iin_wMaxPacketSize, urb->actual_length);
2357 fallthrough;
2358 default:
2359 /* urb terminated, clean up */
2360 dev_dbg(dev, "urb terminated, status: %d\n", status);
2361 return;
2362 }
2363exit:
2364 rv = usb_submit_urb(urb, GFP_ATOMIC);
2365 if (rv)
2366 dev_err(dev, "usb_submit_urb failed: %d\n", rv);
2367}
2368
2369static void usbtmc_free_int(struct usbtmc_device_data *data)
2370{
2371 if (!data->iin_ep_present || !data->iin_urb)
2372 return;
2373 usb_kill_urb(data->iin_urb);
2374 kfree(data->iin_buffer);
2375 data->iin_buffer = NULL;
2376 usb_free_urb(data->iin_urb);
2377 data->iin_urb = NULL;
2378 kref_put(&data->kref, usbtmc_delete);
2379}
2380
2381static int usbtmc_probe(struct usb_interface *intf,
2382 const struct usb_device_id *id)
2383{
2384 struct usbtmc_device_data *data;
2385 struct usb_host_interface *iface_desc;
2386 struct usb_endpoint_descriptor *bulk_in, *bulk_out, *int_in;
2387 int retcode;
2388
2389 dev_dbg(&intf->dev, "%s called\n", __func__);
2390
2391 data = kzalloc_obj(*data);
2392 if (!data)
2393 return -ENOMEM;
2394
2395 data->intf = intf;
2396 data->usb_dev = usb_get_dev(interface_to_usbdev(intf));
2397 usb_set_intfdata(intf, data);
2398 kref_init(&data->kref);
2399 mutex_init(&data->io_mutex);
2400 init_waitqueue_head(&data->waitq);
2401 atomic_set(&data->iin_data_valid, 0);
2402 INIT_LIST_HEAD(&data->file_list);
2403 spin_lock_init(&data->dev_lock);
2404
2405 data->zombie = 0;
2406
2407 /* Initialize USBTMC bTag and other fields */
2408 data->bTag = 1;
2409 /* 2 <= bTag <= 127 USBTMC-USB488 subclass specification 4.3.1 */
2410 data->iin_bTag = 2;
2411
2412 /* USBTMC devices have only one setting, so use that */
2413 iface_desc = data->intf->cur_altsetting;
2414 data->ifnum = iface_desc->desc.bInterfaceNumber;
2415
2416 /* Find bulk endpoints */
2417 retcode = usb_find_common_endpoints(iface_desc,
2418 &bulk_in, &bulk_out, NULL, NULL);
2419 if (retcode) {
2420 dev_err(&intf->dev, "bulk endpoints not found\n");
2421 goto err_put;
2422 }
2423
2424 retcode = -EINVAL;
2425 data->bulk_in = bulk_in->bEndpointAddress;
2426 data->wMaxPacketSize = usb_endpoint_maxp(bulk_in);
2427 if (!data->wMaxPacketSize)
2428 goto err_put;
2429 dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n", data->bulk_in);
2430
2431 data->bulk_out = bulk_out->bEndpointAddress;
2432 dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n", data->bulk_out);
2433
2434 /* Find int endpoint */
2435 retcode = usb_find_int_in_endpoint(iface_desc, &int_in);
2436 if (!retcode) {
2437 data->iin_ep_present = 1;
2438 data->iin_ep = int_in->bEndpointAddress;
2439 data->iin_wMaxPacketSize = usb_endpoint_maxp(int_in);
2440 data->iin_interval = int_in->bInterval;
2441 /* wMaxPacketSize should be 0x02 or more as per USB488 Table 22 */
2442 if (iface_desc->desc.bInterfaceProtocol == 1 &&
2443 data->iin_wMaxPacketSize < 2) {
2444 retcode = -EINVAL;
2445 goto err_put;
2446 }
2447 dev_dbg(&intf->dev, "Found Int in endpoint at %u\n",
2448 data->iin_ep);
2449 }
2450
2451 retcode = get_capabilities(data);
2452 if (retcode)
2453 dev_err(&intf->dev, "can't read capabilities\n");
2454
2455 if (data->iin_ep_present) {
2456 /* allocate int urb */
2457 data->iin_urb = usb_alloc_urb(0, GFP_KERNEL);
2458 if (!data->iin_urb) {
2459 retcode = -ENOMEM;
2460 goto error_register;
2461 }
2462
2463 /* Protect interrupt in endpoint data until iin_urb is freed */
2464 kref_get(&data->kref);
2465
2466 /* allocate buffer for interrupt in */
2467 data->iin_buffer = kmalloc(data->iin_wMaxPacketSize,
2468 GFP_KERNEL);
2469 if (!data->iin_buffer) {
2470 retcode = -ENOMEM;
2471 goto error_register;
2472 }
2473
2474 /* fill interrupt urb */
2475 usb_fill_int_urb(data->iin_urb, data->usb_dev,
2476 usb_rcvintpipe(data->usb_dev, data->iin_ep),
2477 data->iin_buffer, data->iin_wMaxPacketSize,
2478 usbtmc_interrupt,
2479 data, data->iin_interval);
2480
2481 retcode = usb_submit_urb(data->iin_urb, GFP_KERNEL);
2482 if (retcode) {
2483 dev_err(&intf->dev, "Failed to submit iin_urb\n");
2484 goto error_register;
2485 }
2486 }
2487
2488 retcode = usb_register_dev(intf, &usbtmc_class);
2489 if (retcode) {
2490 dev_err(&intf->dev, "Not able to get a minor (base %u, slice default): %d\n",
2491 USBTMC_MINOR_BASE,
2492 retcode);
2493 goto error_register;
2494 }
2495 dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor);
2496
2497 return 0;
2498
2499error_register:
2500 usbtmc_free_int(data);
2501err_put:
2502 kref_put(&data->kref, usbtmc_delete);
2503 return retcode;
2504}
2505
2506static void usbtmc_disconnect(struct usb_interface *intf)
2507{
2508 struct usbtmc_device_data *data = usb_get_intfdata(intf);
2509 struct list_head *elem;
2510
2511 usb_deregister_dev(intf, &usbtmc_class);
2512 mutex_lock(&data->io_mutex);
2513 data->zombie = 1;
2514 wake_up_interruptible_all(&data->waitq);
2515 list_for_each(elem, &data->file_list) {
2516 struct usbtmc_file_data *file_data;
2517
2518 file_data = list_entry(elem,
2519 struct usbtmc_file_data,
2520 file_elem);
2521 usb_kill_anchored_urbs(&file_data->submitted);
2522 usb_scuttle_anchored_urbs(&file_data->in_anchor);
2523 }
2524 mutex_unlock(&data->io_mutex);
2525 usbtmc_free_int(data);
2526 kref_put(&data->kref, usbtmc_delete);
2527}
2528
2529static void usbtmc_draw_down(struct usbtmc_file_data *file_data)
2530{
2531 int time;
2532
2533 time = usb_wait_anchor_empty_timeout(&file_data->submitted, 1000);
2534 if (!time)
2535 usb_kill_anchored_urbs(&file_data->submitted);
2536 usb_scuttle_anchored_urbs(&file_data->in_anchor);
2537}
2538
2539static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message)
2540{
2541 struct usbtmc_device_data *data = usb_get_intfdata(intf);
2542 struct list_head *elem;
2543
2544 if (!data)
2545 return 0;
2546
2547 mutex_lock(&data->io_mutex);
2548 list_for_each(elem, &data->file_list) {
2549 struct usbtmc_file_data *file_data;
2550
2551 file_data = list_entry(elem,
2552 struct usbtmc_file_data,
2553 file_elem);
2554 usbtmc_draw_down(file_data);
2555 }
2556
2557 if (data->iin_ep_present && data->iin_urb)
2558 usb_kill_urb(data->iin_urb);
2559
2560 mutex_unlock(&data->io_mutex);
2561 return 0;
2562}
2563
2564static int usbtmc_resume(struct usb_interface *intf)
2565{
2566 struct usbtmc_device_data *data = usb_get_intfdata(intf);
2567 int retcode = 0;
2568
2569 if (data->iin_ep_present && data->iin_urb)
2570 retcode = usb_submit_urb(data->iin_urb, GFP_KERNEL);
2571 if (retcode)
2572 dev_err(&intf->dev, "Failed to submit iin_urb\n");
2573
2574 return retcode;
2575}
2576
2577static int usbtmc_pre_reset(struct usb_interface *intf)
2578{
2579 struct usbtmc_device_data *data = usb_get_intfdata(intf);
2580 struct list_head *elem;
2581
2582 if (!data)
2583 return 0;
2584
2585 mutex_lock(&data->io_mutex);
2586
2587 list_for_each(elem, &data->file_list) {
2588 struct usbtmc_file_data *file_data;
2589
2590 file_data = list_entry(elem,
2591 struct usbtmc_file_data,
2592 file_elem);
2593 usbtmc_ioctl_cancel_io(file_data);
2594 }
2595
2596 return 0;
2597}
2598
2599static int usbtmc_post_reset(struct usb_interface *intf)
2600{
2601 struct usbtmc_device_data *data = usb_get_intfdata(intf);
2602
2603 mutex_unlock(&data->io_mutex);
2604
2605 return 0;
2606}
2607
2608static struct usb_driver usbtmc_driver = {
2609 .name = "usbtmc",
2610 .id_table = usbtmc_devices,
2611 .probe = usbtmc_probe,
2612 .disconnect = usbtmc_disconnect,
2613 .suspend = usbtmc_suspend,
2614 .resume = usbtmc_resume,
2615 .pre_reset = usbtmc_pre_reset,
2616 .post_reset = usbtmc_post_reset,
2617 .dev_groups = usbtmc_groups,
2618};
2619
2620module_usb_driver(usbtmc_driver);
2621
2622MODULE_DESCRIPTION("USB Test & Measurement class driver");
2623MODULE_LICENSE("GPL");