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