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v3.1
 
   1/**
   2 * drivers/usb/class/usbtmc.c - USB Test & Measurement class driver
   3 *
   4 * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany
   5 * Copyright (C) 2008 Novell, Inc.
   6 * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License
  10 * as published by the Free Software Foundation; either version 2
  11 * of the License, or (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * The GNU General Public License is available at
  19 * http://www.gnu.org/copyleft/gpl.html.
  20 */
  21
  22#include <linux/init.h>
 
  23#include <linux/module.h>
  24#include <linux/kernel.h>
  25#include <linux/fs.h>
  26#include <linux/uaccess.h>
  27#include <linux/kref.h>
  28#include <linux/slab.h>
 
  29#include <linux/mutex.h>
  30#include <linux/usb.h>
  31#include <linux/usb/tmc.h>
  32
  33
 
 
  34#define USBTMC_MINOR_BASE	176
  35
  36/*
  37 * Size of driver internal IO buffer. Must be multiple of 4 and at least as
  38 * large as wMaxPacketSize (which is usually 512 bytes).
  39 */
  40#define USBTMC_SIZE_IOBUFFER	2048
  41
  42/* Default USB timeout (in milliseconds) */
  43#define USBTMC_TIMEOUT		5000
  44
  45/*
  46 * Maximum number of read cycles to empty bulk in endpoint during CLEAR and
  47 * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
  48 * packet is never read.
  49 */
  50#define USBTMC_MAX_READS_TO_CLEAR_BULK_IN	100
  51
  52static const struct usb_device_id usbtmc_devices[] = {
  53	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), },
  54	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), },
  55	{ 0, } /* terminating entry */
  56};
  57MODULE_DEVICE_TABLE(usb, usbtmc_devices);
  58
  59/*
  60 * This structure is the capabilities for the device
  61 * See section 4.2.1.8 of the USBTMC specification,
  62 * and section 4.2.2 of the USBTMC usb488 subclass
  63 * specification for details.
  64 */
  65struct usbtmc_dev_capabilities {
  66	__u8 interface_capabilities;
  67	__u8 device_capabilities;
  68	__u8 usb488_interface_capabilities;
  69	__u8 usb488_device_capabilities;
  70};
  71
  72/* This structure holds private data for each USBTMC device. One copy is
  73 * allocated for each USBTMC device in the driver's probe function.
  74 */
  75struct usbtmc_device_data {
  76	const struct usb_device_id *id;
  77	struct usb_device *usb_dev;
  78	struct usb_interface *intf;
  79
  80	unsigned int bulk_in;
  81	unsigned int bulk_out;
  82
  83	u8 bTag;
  84	u8 bTag_last_write;	/* needed for abort */
  85	u8 bTag_last_read;	/* needed for abort */
  86
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  87	/* attributes from the USB TMC spec for this device */
  88	u8 TermChar;
  89	bool TermCharEnabled;
  90	bool auto_abort;
  91
  92	bool zombie; /* fd of disconnected device */
  93
  94	struct usbtmc_dev_capabilities	capabilities;
  95	struct kref kref;
  96	struct mutex io_mutex;	/* only one i/o function running at a time */
 
 
  97};
  98#define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref)
  99
 
 
 
 
 
 
 
 
 
 
 
 100/* Forward declarations */
 101static struct usb_driver usbtmc_driver;
 102
 103static void usbtmc_delete(struct kref *kref)
 104{
 105	struct usbtmc_device_data *data = to_usbtmc_data(kref);
 106
 107	usb_put_dev(data->usb_dev);
 108	kfree(data);
 109}
 110
 111static int usbtmc_open(struct inode *inode, struct file *filp)
 112{
 113	struct usb_interface *intf;
 114	struct usbtmc_device_data *data;
 115	int retval = 0;
 116
 117	intf = usb_find_interface(&usbtmc_driver, iminor(inode));
 118	if (!intf) {
 119		printk(KERN_ERR KBUILD_MODNAME
 120		       ": can not find device for minor %d", iminor(inode));
 121		retval = -ENODEV;
 122		goto exit;
 123	}
 124
 125	data = usb_get_intfdata(intf);
 
 126	kref_get(&data->kref);
 127
 128	/* Store pointer in file structure's private data field */
 129	filp->private_data = data;
 130
 131exit:
 132	return retval;
 133}
 134
 135static int usbtmc_release(struct inode *inode, struct file *file)
 136{
 137	struct usbtmc_device_data *data = file->private_data;
 138
 139	kref_put(&data->kref, usbtmc_delete);
 140	return 0;
 141}
 142
 143static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data)
 144{
 145	u8 *buffer;
 146	struct device *dev;
 147	int rv;
 148	int n;
 149	int actual;
 150	struct usb_host_interface *current_setting;
 151	int max_size;
 152
 153	dev = &data->intf->dev;
 154	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 155	if (!buffer)
 156		return -ENOMEM;
 157
 158	rv = usb_control_msg(data->usb_dev,
 159			     usb_rcvctrlpipe(data->usb_dev, 0),
 160			     USBTMC_REQUEST_INITIATE_ABORT_BULK_IN,
 161			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 162			     data->bTag_last_read, data->bulk_in,
 163			     buffer, 2, USBTMC_TIMEOUT);
 164
 165	if (rv < 0) {
 166		dev_err(dev, "usb_control_msg returned %d\n", rv);
 167		goto exit;
 168	}
 169
 170	dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 171
 172	if (buffer[0] == USBTMC_STATUS_FAILED) {
 173		rv = 0;
 174		goto exit;
 175	}
 176
 177	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 178		dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n",
 179			buffer[0]);
 180		rv = -EPERM;
 181		goto exit;
 182	}
 183
 184	max_size = 0;
 185	current_setting = data->intf->cur_altsetting;
 186	for (n = 0; n < current_setting->desc.bNumEndpoints; n++)
 187		if (current_setting->endpoint[n].desc.bEndpointAddress ==
 188			data->bulk_in)
 189			max_size = le16_to_cpu(current_setting->endpoint[n].
 190						desc.wMaxPacketSize);
 191
 192	if (max_size == 0) {
 193		dev_err(dev, "Couldn't get wMaxPacketSize\n");
 194		rv = -EPERM;
 195		goto exit;
 196	}
 197
 198	dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size);
 199
 200	n = 0;
 201
 202	do {
 203		dev_dbg(dev, "Reading from bulk in EP\n");
 204
 205		rv = usb_bulk_msg(data->usb_dev,
 206				  usb_rcvbulkpipe(data->usb_dev,
 207						  data->bulk_in),
 208				  buffer, USBTMC_SIZE_IOBUFFER,
 209				  &actual, USBTMC_TIMEOUT);
 210
 211		n++;
 212
 213		if (rv < 0) {
 214			dev_err(dev, "usb_bulk_msg returned %d\n", rv);
 215			goto exit;
 216		}
 217	} while ((actual == max_size) &&
 218		 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 219
 220	if (actual == max_size) {
 221		dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 222			USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 223		rv = -EPERM;
 224		goto exit;
 225	}
 226
 227	n = 0;
 228
 229usbtmc_abort_bulk_in_status:
 230	rv = usb_control_msg(data->usb_dev,
 231			     usb_rcvctrlpipe(data->usb_dev, 0),
 232			     USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS,
 233			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 234			     0, data->bulk_in, buffer, 0x08,
 235			     USBTMC_TIMEOUT);
 236
 237	if (rv < 0) {
 238		dev_err(dev, "usb_control_msg returned %d\n", rv);
 239		goto exit;
 240	}
 241
 242	dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 243
 244	if (buffer[0] == USBTMC_STATUS_SUCCESS) {
 245		rv = 0;
 246		goto exit;
 247	}
 248
 249	if (buffer[0] != USBTMC_STATUS_PENDING) {
 250		dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 251		rv = -EPERM;
 252		goto exit;
 253	}
 254
 255	if (buffer[1] == 1)
 256		do {
 257			dev_dbg(dev, "Reading from bulk in EP\n");
 258
 259			rv = usb_bulk_msg(data->usb_dev,
 260					  usb_rcvbulkpipe(data->usb_dev,
 261							  data->bulk_in),
 262					  buffer, USBTMC_SIZE_IOBUFFER,
 263					  &actual, USBTMC_TIMEOUT);
 264
 265			n++;
 266
 267			if (rv < 0) {
 268				dev_err(dev, "usb_bulk_msg returned %d\n", rv);
 269				goto exit;
 270			}
 271		} while ((actual == max_size) &&
 272			 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 273
 274	if (actual == max_size) {
 275		dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 276			USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 277		rv = -EPERM;
 278		goto exit;
 279	}
 280
 281	goto usbtmc_abort_bulk_in_status;
 282
 283exit:
 284	kfree(buffer);
 285	return rv;
 286
 287}
 288
 289static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
 290{
 291	struct device *dev;
 292	u8 *buffer;
 293	int rv;
 294	int n;
 295
 296	dev = &data->intf->dev;
 297
 298	buffer = kmalloc(8, GFP_KERNEL);
 299	if (!buffer)
 300		return -ENOMEM;
 301
 302	rv = usb_control_msg(data->usb_dev,
 303			     usb_rcvctrlpipe(data->usb_dev, 0),
 304			     USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT,
 305			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 306			     data->bTag_last_write, data->bulk_out,
 307			     buffer, 2, USBTMC_TIMEOUT);
 308
 309	if (rv < 0) {
 310		dev_err(dev, "usb_control_msg returned %d\n", rv);
 311		goto exit;
 312	}
 313
 314	dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]);
 315
 316	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 317		dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n",
 318			buffer[0]);
 319		rv = -EPERM;
 320		goto exit;
 321	}
 322
 323	n = 0;
 324
 325usbtmc_abort_bulk_out_check_status:
 326	rv = usb_control_msg(data->usb_dev,
 327			     usb_rcvctrlpipe(data->usb_dev, 0),
 328			     USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS,
 329			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 330			     0, data->bulk_out, buffer, 0x08,
 331			     USBTMC_TIMEOUT);
 332	n++;
 333	if (rv < 0) {
 334		dev_err(dev, "usb_control_msg returned %d\n", rv);
 335		goto exit;
 336	}
 337
 338	dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]);
 339
 340	if (buffer[0] == USBTMC_STATUS_SUCCESS)
 341		goto usbtmc_abort_bulk_out_clear_halt;
 342
 343	if ((buffer[0] == USBTMC_STATUS_PENDING) &&
 344	    (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN))
 345		goto usbtmc_abort_bulk_out_check_status;
 346
 347	rv = -EPERM;
 348	goto exit;
 349
 350usbtmc_abort_bulk_out_clear_halt:
 351	rv = usb_clear_halt(data->usb_dev,
 352			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 353
 354	if (rv < 0) {
 355		dev_err(dev, "usb_control_msg returned %d\n", rv);
 356		goto exit;
 357	}
 358	rv = 0;
 359
 360exit:
 361	kfree(buffer);
 362	return rv;
 363}
 364
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 365static ssize_t usbtmc_read(struct file *filp, char __user *buf,
 366			   size_t count, loff_t *f_pos)
 367{
 368	struct usbtmc_device_data *data;
 369	struct device *dev;
 370	u32 n_characters;
 371	u8 *buffer;
 372	int actual;
 373	size_t done;
 374	size_t remaining;
 375	int retval;
 376	size_t this_part;
 377
 378	/* Get pointer to private data structure */
 379	data = filp->private_data;
 380	dev = &data->intf->dev;
 381
 382	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 383	if (!buffer)
 384		return -ENOMEM;
 385
 386	mutex_lock(&data->io_mutex);
 387	if (data->zombie) {
 388		retval = -ENODEV;
 389		goto exit;
 390	}
 391
 392	remaining = count;
 393	done = 0;
 394
 395	while (remaining > 0) {
 396		if (remaining > USBTMC_SIZE_IOBUFFER - 12 - 3)
 397			this_part = USBTMC_SIZE_IOBUFFER - 12 - 3;
 398		else
 399			this_part = remaining;
 400
 401		/* Setup IO buffer for DEV_DEP_MSG_IN message
 402		 * Refer to class specs for details
 403		 */
 404		buffer[0] = 2;
 405		buffer[1] = data->bTag;
 406		buffer[2] = ~(data->bTag);
 407		buffer[3] = 0; /* Reserved */
 408		buffer[4] = (this_part) & 255;
 409		buffer[5] = ((this_part) >> 8) & 255;
 410		buffer[6] = ((this_part) >> 16) & 255;
 411		buffer[7] = ((this_part) >> 24) & 255;
 412		buffer[8] = data->TermCharEnabled * 2;
 413		/* Use term character? */
 414		buffer[9] = data->TermChar;
 415		buffer[10] = 0; /* Reserved */
 416		buffer[11] = 0; /* Reserved */
 417
 418		/* Send bulk URB */
 419		retval = usb_bulk_msg(data->usb_dev,
 420				      usb_sndbulkpipe(data->usb_dev,
 421						      data->bulk_out),
 422				      buffer, 12, &actual, USBTMC_TIMEOUT);
 423
 424		/* Store bTag (in case we need to abort) */
 425		data->bTag_last_write = data->bTag;
 
 426
 427		/* Increment bTag -- and increment again if zero */
 428		data->bTag++;
 429		if (!data->bTag)
 430			(data->bTag)++;
 431
 432		if (retval < 0) {
 
 433			dev_err(dev, "usb_bulk_msg returned %d\n", retval);
 434			if (data->auto_abort)
 435				usbtmc_ioctl_abort_bulk_out(data);
 436			goto exit;
 
 437		}
 438
 439		/* Send bulk URB */
 440		retval = usb_bulk_msg(data->usb_dev,
 441				      usb_rcvbulkpipe(data->usb_dev,
 442						      data->bulk_in),
 443				      buffer, USBTMC_SIZE_IOBUFFER, &actual,
 444				      USBTMC_TIMEOUT);
 445
 
 
 446		/* Store bTag (in case we need to abort) */
 447		data->bTag_last_read = data->bTag;
 448
 449		if (retval < 0) {
 450			dev_err(dev, "Unable to read data, error %d\n", retval);
 451			if (data->auto_abort)
 452				usbtmc_ioctl_abort_bulk_in(data);
 453			goto exit;
 454		}
 455
 456		/* How many characters did the instrument send? */
 457		n_characters = buffer[4] +
 458			       (buffer[5] << 8) +
 459			       (buffer[6] << 16) +
 460			       (buffer[7] << 24);
 461
 462		/* Ensure the instrument doesn't lie about it */
 463		if(n_characters > actual - 12) {
 464			dev_err(dev, "Device lies about message size: %u > %d\n", n_characters, actual - 12);
 465			n_characters = actual - 12;
 466		}
 467
 468		/* Ensure the instrument doesn't send more back than requested */
 469		if(n_characters > this_part) {
 470			dev_err(dev, "Device returns more than requested: %zu > %zu\n", done + n_characters, done + this_part);
 471			n_characters = this_part;
 472		}
 
 473
 474		/* Bound amount of data received by amount of data requested */
 475		if (n_characters > this_part)
 476			n_characters = this_part;
 477
 478		/* Copy buffer to user space */
 479		if (copy_to_user(buf + done, &buffer[12], n_characters)) {
 480			/* There must have been an addressing problem */
 481			retval = -EFAULT;
 482			goto exit;
 483		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 484
 485		done += n_characters;
 486		/* Terminate if end-of-message bit received from device */
 487		if ((buffer[8] &  0x01) && (actual >= n_characters + 12))
 488			remaining = 0;
 489		else
 490			remaining -= n_characters;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 491	}
 492
 493	/* Update file position value */
 494	*f_pos = *f_pos + done;
 495	retval = done;
 496
 497exit:
 498	mutex_unlock(&data->io_mutex);
 499	kfree(buffer);
 500	return retval;
 501}
 502
 503static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
 504			    size_t count, loff_t *f_pos)
 505{
 506	struct usbtmc_device_data *data;
 507	u8 *buffer;
 508	int retval;
 509	int actual;
 510	unsigned long int n_bytes;
 511	int remaining;
 512	int done;
 513	int this_part;
 514
 515	data = filp->private_data;
 516
 517	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 518	if (!buffer)
 519		return -ENOMEM;
 520
 521	mutex_lock(&data->io_mutex);
 522	if (data->zombie) {
 523		retval = -ENODEV;
 524		goto exit;
 525	}
 526
 527	remaining = count;
 528	done = 0;
 529
 530	while (remaining > 0) {
 531		if (remaining > USBTMC_SIZE_IOBUFFER - 12) {
 532			this_part = USBTMC_SIZE_IOBUFFER - 12;
 533			buffer[8] = 0;
 534		} else {
 535			this_part = remaining;
 536			buffer[8] = 1;
 537		}
 538
 539		/* Setup IO buffer for DEV_DEP_MSG_OUT message */
 540		buffer[0] = 1;
 541		buffer[1] = data->bTag;
 542		buffer[2] = ~(data->bTag);
 543		buffer[3] = 0; /* Reserved */
 544		buffer[4] = this_part & 255;
 545		buffer[5] = (this_part >> 8) & 255;
 546		buffer[6] = (this_part >> 16) & 255;
 547		buffer[7] = (this_part >> 24) & 255;
 548		/* buffer[8] is set above... */
 549		buffer[9] = 0; /* Reserved */
 550		buffer[10] = 0; /* Reserved */
 551		buffer[11] = 0; /* Reserved */
 552
 553		if (copy_from_user(&buffer[12], buf + done, this_part)) {
 554			retval = -EFAULT;
 555			goto exit;
 556		}
 557
 558		n_bytes = roundup(12 + this_part, 4);
 559		memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part));
 560
 561		do {
 562			retval = usb_bulk_msg(data->usb_dev,
 563					      usb_sndbulkpipe(data->usb_dev,
 564							      data->bulk_out),
 565					      buffer, n_bytes,
 566					      &actual, USBTMC_TIMEOUT);
 567			if (retval != 0)
 568				break;
 569			n_bytes -= actual;
 570		} while (n_bytes);
 571
 572		data->bTag_last_write = data->bTag;
 573		data->bTag++;
 574
 575		if (!data->bTag)
 576			data->bTag++;
 577
 578		if (retval < 0) {
 579			dev_err(&data->intf->dev,
 580				"Unable to send data, error %d\n", retval);
 581			if (data->auto_abort)
 582				usbtmc_ioctl_abort_bulk_out(data);
 583			goto exit;
 584		}
 585
 586		remaining -= this_part;
 587		done += this_part;
 588	}
 589
 590	retval = count;
 591exit:
 592	mutex_unlock(&data->io_mutex);
 593	kfree(buffer);
 594	return retval;
 595}
 596
 597static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
 598{
 599	struct usb_host_interface *current_setting;
 600	struct usb_endpoint_descriptor *desc;
 601	struct device *dev;
 602	u8 *buffer;
 603	int rv;
 604	int n;
 605	int actual;
 606	int max_size;
 607
 608	dev = &data->intf->dev;
 609
 610	dev_dbg(dev, "Sending INITIATE_CLEAR request\n");
 611
 612	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 613	if (!buffer)
 614		return -ENOMEM;
 615
 616	rv = usb_control_msg(data->usb_dev,
 617			     usb_rcvctrlpipe(data->usb_dev, 0),
 618			     USBTMC_REQUEST_INITIATE_CLEAR,
 619			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 620			     0, 0, buffer, 1, USBTMC_TIMEOUT);
 621	if (rv < 0) {
 622		dev_err(dev, "usb_control_msg returned %d\n", rv);
 623		goto exit;
 624	}
 625
 626	dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
 627
 628	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 629		dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
 630		rv = -EPERM;
 631		goto exit;
 632	}
 633
 634	max_size = 0;
 635	current_setting = data->intf->cur_altsetting;
 636	for (n = 0; n < current_setting->desc.bNumEndpoints; n++) {
 637		desc = &current_setting->endpoint[n].desc;
 638		if (desc->bEndpointAddress == data->bulk_in)
 639			max_size = le16_to_cpu(desc->wMaxPacketSize);
 640	}
 641
 642	if (max_size == 0) {
 643		dev_err(dev, "Couldn't get wMaxPacketSize\n");
 644		rv = -EPERM;
 645		goto exit;
 646	}
 647
 648	dev_dbg(dev, "wMaxPacketSize is %d\n", max_size);
 649
 650	n = 0;
 651
 652usbtmc_clear_check_status:
 653
 654	dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n");
 655
 656	rv = usb_control_msg(data->usb_dev,
 657			     usb_rcvctrlpipe(data->usb_dev, 0),
 658			     USBTMC_REQUEST_CHECK_CLEAR_STATUS,
 659			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 660			     0, 0, buffer, 2, USBTMC_TIMEOUT);
 661	if (rv < 0) {
 662		dev_err(dev, "usb_control_msg returned %d\n", rv);
 663		goto exit;
 664	}
 665
 666	dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
 667
 668	if (buffer[0] == USBTMC_STATUS_SUCCESS)
 669		goto usbtmc_clear_bulk_out_halt;
 670
 671	if (buffer[0] != USBTMC_STATUS_PENDING) {
 672		dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
 673		rv = -EPERM;
 674		goto exit;
 675	}
 676
 677	if (buffer[1] == 1)
 678		do {
 679			dev_dbg(dev, "Reading from bulk in EP\n");
 680
 681			rv = usb_bulk_msg(data->usb_dev,
 682					  usb_rcvbulkpipe(data->usb_dev,
 683							  data->bulk_in),
 684					  buffer, USBTMC_SIZE_IOBUFFER,
 685					  &actual, USBTMC_TIMEOUT);
 686			n++;
 687
 688			if (rv < 0) {
 689				dev_err(dev, "usb_control_msg returned %d\n",
 690					rv);
 691				goto exit;
 692			}
 693		} while ((actual == max_size) &&
 694			  (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 695
 696	if (actual == max_size) {
 697		dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 698			USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 699		rv = -EPERM;
 700		goto exit;
 701	}
 702
 703	goto usbtmc_clear_check_status;
 704
 705usbtmc_clear_bulk_out_halt:
 706
 707	rv = usb_clear_halt(data->usb_dev,
 708			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 709	if (rv < 0) {
 710		dev_err(dev, "usb_control_msg returned %d\n", rv);
 711		goto exit;
 712	}
 713	rv = 0;
 714
 715exit:
 716	kfree(buffer);
 717	return rv;
 718}
 719
 720static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
 721{
 722	u8 *buffer;
 723	int rv;
 724
 725	buffer = kmalloc(2, GFP_KERNEL);
 726	if (!buffer)
 727		return -ENOMEM;
 728
 729	rv = usb_clear_halt(data->usb_dev,
 730			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 731
 732	if (rv < 0) {
 733		dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
 734			rv);
 735		goto exit;
 736	}
 737	rv = 0;
 738
 739exit:
 740	kfree(buffer);
 741	return rv;
 742}
 743
 744static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
 745{
 746	u8 *buffer;
 747	int rv;
 748
 749	buffer = kmalloc(2, GFP_KERNEL);
 750	if (!buffer)
 751		return -ENOMEM;
 752
 753	rv = usb_clear_halt(data->usb_dev,
 754			    usb_rcvbulkpipe(data->usb_dev, data->bulk_in));
 755
 756	if (rv < 0) {
 757		dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
 758			rv);
 759		goto exit;
 760	}
 761	rv = 0;
 762
 763exit:
 764	kfree(buffer);
 765	return rv;
 766}
 767
 768static int get_capabilities(struct usbtmc_device_data *data)
 769{
 770	struct device *dev = &data->usb_dev->dev;
 771	char *buffer;
 772	int rv = 0;
 773
 774	buffer = kmalloc(0x18, GFP_KERNEL);
 775	if (!buffer)
 776		return -ENOMEM;
 777
 778	rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0),
 779			     USBTMC_REQUEST_GET_CAPABILITIES,
 780			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 781			     0, 0, buffer, 0x18, USBTMC_TIMEOUT);
 782	if (rv < 0) {
 783		dev_err(dev, "usb_control_msg returned %d\n", rv);
 784		goto err_out;
 785	}
 786
 787	dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
 788	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 789		dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
 790		rv = -EPERM;
 791		goto err_out;
 792	}
 793	dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
 794	dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
 795	dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
 796	dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
 797
 798	data->capabilities.interface_capabilities = buffer[4];
 799	data->capabilities.device_capabilities = buffer[5];
 800	data->capabilities.usb488_interface_capabilities = buffer[14];
 801	data->capabilities.usb488_device_capabilities = buffer[15];
 
 802	rv = 0;
 803
 804err_out:
 805	kfree(buffer);
 806	return rv;
 807}
 808
 809#define capability_attribute(name)					\
 810static ssize_t show_##name(struct device *dev,				\
 811			   struct device_attribute *attr, char *buf)	\
 812{									\
 813	struct usb_interface *intf = to_usb_interface(dev);		\
 814	struct usbtmc_device_data *data = usb_get_intfdata(intf);	\
 815									\
 816	return sprintf(buf, "%d\n", data->capabilities.name);		\
 817}									\
 818static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 819
 820capability_attribute(interface_capabilities);
 821capability_attribute(device_capabilities);
 822capability_attribute(usb488_interface_capabilities);
 823capability_attribute(usb488_device_capabilities);
 824
 825static struct attribute *capability_attrs[] = {
 826	&dev_attr_interface_capabilities.attr,
 827	&dev_attr_device_capabilities.attr,
 828	&dev_attr_usb488_interface_capabilities.attr,
 829	&dev_attr_usb488_device_capabilities.attr,
 830	NULL,
 831};
 832
 833static struct attribute_group capability_attr_grp = {
 834	.attrs = capability_attrs,
 835};
 836
 837static ssize_t show_TermChar(struct device *dev,
 838			     struct device_attribute *attr, char *buf)
 839{
 840	struct usb_interface *intf = to_usb_interface(dev);
 841	struct usbtmc_device_data *data = usb_get_intfdata(intf);
 842
 843	return sprintf(buf, "%c\n", data->TermChar);
 844}
 845
 846static ssize_t store_TermChar(struct device *dev,
 847			      struct device_attribute *attr,
 848			      const char *buf, size_t count)
 849{
 850	struct usb_interface *intf = to_usb_interface(dev);
 851	struct usbtmc_device_data *data = usb_get_intfdata(intf);
 852
 853	if (count < 1)
 854		return -EINVAL;
 855	data->TermChar = buf[0];
 856	return count;
 857}
 858static DEVICE_ATTR(TermChar, S_IRUGO, show_TermChar, store_TermChar);
 859
 860#define data_attribute(name)						\
 861static ssize_t show_##name(struct device *dev,				\
 862			   struct device_attribute *attr, char *buf)	\
 863{									\
 864	struct usb_interface *intf = to_usb_interface(dev);		\
 865	struct usbtmc_device_data *data = usb_get_intfdata(intf);	\
 866									\
 867	return sprintf(buf, "%d\n", data->name);			\
 868}									\
 869static ssize_t store_##name(struct device *dev,				\
 870			    struct device_attribute *attr,		\
 871			    const char *buf, size_t count)		\
 872{									\
 873	struct usb_interface *intf = to_usb_interface(dev);		\
 874	struct usbtmc_device_data *data = usb_get_intfdata(intf);	\
 875	ssize_t result;							\
 876	unsigned val;							\
 877									\
 878	result = sscanf(buf, "%u\n", &val);				\
 879	if (result != 1)						\
 880		result = -EINVAL;					\
 881	data->name = val;						\
 882	if (result < 0)							\
 883		return result;						\
 884	else								\
 885		return count;						\
 886}									\
 887static DEVICE_ATTR(name, S_IRUGO, show_##name, store_##name)
 888
 889data_attribute(TermCharEnabled);
 890data_attribute(auto_abort);
 891
 892static struct attribute *data_attrs[] = {
 893	&dev_attr_TermChar.attr,
 894	&dev_attr_TermCharEnabled.attr,
 895	&dev_attr_auto_abort.attr,
 896	NULL,
 897};
 898
 899static struct attribute_group data_attr_grp = {
 900	.attrs = data_attrs,
 901};
 902
 903static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data)
 904{
 905	struct device *dev;
 906	u8 *buffer;
 907	int rv;
 908
 909	dev = &data->intf->dev;
 910
 911	buffer = kmalloc(2, GFP_KERNEL);
 912	if (!buffer)
 913		return -ENOMEM;
 914
 915	rv = usb_control_msg(data->usb_dev,
 916			     usb_rcvctrlpipe(data->usb_dev, 0),
 917			     USBTMC_REQUEST_INDICATOR_PULSE,
 918			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 919			     0, 0, buffer, 0x01, USBTMC_TIMEOUT);
 920
 921	if (rv < 0) {
 922		dev_err(dev, "usb_control_msg returned %d\n", rv);
 923		goto exit;
 924	}
 925
 926	dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
 927
 928	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 929		dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
 930		rv = -EPERM;
 931		goto exit;
 932	}
 933	rv = 0;
 934
 935exit:
 936	kfree(buffer);
 937	return rv;
 938}
 939
 940static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 941{
 942	struct usbtmc_device_data *data;
 943	int retval = -EBADRQC;
 944
 945	data = file->private_data;
 946	mutex_lock(&data->io_mutex);
 947	if (data->zombie) {
 948		retval = -ENODEV;
 949		goto skip_io_on_zombie;
 950	}
 951
 952	switch (cmd) {
 953	case USBTMC_IOCTL_CLEAR_OUT_HALT:
 954		retval = usbtmc_ioctl_clear_out_halt(data);
 955		break;
 956
 957	case USBTMC_IOCTL_CLEAR_IN_HALT:
 958		retval = usbtmc_ioctl_clear_in_halt(data);
 959		break;
 960
 961	case USBTMC_IOCTL_INDICATOR_PULSE:
 962		retval = usbtmc_ioctl_indicator_pulse(data);
 963		break;
 964
 965	case USBTMC_IOCTL_CLEAR:
 966		retval = usbtmc_ioctl_clear(data);
 967		break;
 968
 969	case USBTMC_IOCTL_ABORT_BULK_OUT:
 970		retval = usbtmc_ioctl_abort_bulk_out(data);
 971		break;
 972
 973	case USBTMC_IOCTL_ABORT_BULK_IN:
 974		retval = usbtmc_ioctl_abort_bulk_in(data);
 975		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 976	}
 977
 978skip_io_on_zombie:
 979	mutex_unlock(&data->io_mutex);
 980	return retval;
 981}
 982
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 983static const struct file_operations fops = {
 984	.owner		= THIS_MODULE,
 985	.read		= usbtmc_read,
 986	.write		= usbtmc_write,
 987	.open		= usbtmc_open,
 988	.release	= usbtmc_release,
 989	.unlocked_ioctl	= usbtmc_ioctl,
 
 
 990	.llseek		= default_llseek,
 991};
 992
 993static struct usb_class_driver usbtmc_class = {
 994	.name =		"usbtmc%d",
 995	.fops =		&fops,
 996	.minor_base =	USBTMC_MINOR_BASE,
 997};
 998
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 999
1000static int usbtmc_probe(struct usb_interface *intf,
1001			const struct usb_device_id *id)
1002{
1003	struct usbtmc_device_data *data;
1004	struct usb_host_interface *iface_desc;
1005	struct usb_endpoint_descriptor *endpoint;
1006	int n;
1007	int retcode;
1008
1009	dev_dbg(&intf->dev, "%s called\n", __func__);
1010
1011	data = kmalloc(sizeof(struct usbtmc_device_data), GFP_KERNEL);
1012	if (!data) {
1013		dev_err(&intf->dev, "Unable to allocate kernel memory\n");
1014		return -ENOMEM;
1015	}
1016
1017	data->intf = intf;
1018	data->id = id;
1019	data->usb_dev = usb_get_dev(interface_to_usbdev(intf));
1020	usb_set_intfdata(intf, data);
1021	kref_init(&data->kref);
1022	mutex_init(&data->io_mutex);
 
 
 
1023	data->zombie = 0;
1024
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1025	/* Initialize USBTMC bTag and other fields */
1026	data->bTag	= 1;
1027	data->TermCharEnabled = 0;
1028	data->TermChar = '\n';
 
 
1029
1030	/* USBTMC devices have only one setting, so use that */
1031	iface_desc = data->intf->cur_altsetting;
 
1032
1033	/* Find bulk in endpoint */
1034	for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1035		endpoint = &iface_desc->endpoint[n].desc;
1036
1037		if (usb_endpoint_is_bulk_in(endpoint)) {
1038			data->bulk_in = endpoint->bEndpointAddress;
1039			dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n",
1040				data->bulk_in);
1041			break;
1042		}
1043	}
1044
1045	/* Find bulk out endpoint */
1046	for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1047		endpoint = &iface_desc->endpoint[n].desc;
1048
1049		if (usb_endpoint_is_bulk_out(endpoint)) {
1050			data->bulk_out = endpoint->bEndpointAddress;
1051			dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n",
1052				data->bulk_out);
1053			break;
1054		}
 
 
 
 
 
1055	}
1056
1057	retcode = get_capabilities(data);
1058	if (retcode)
1059		dev_err(&intf->dev, "can't read capabilities\n");
1060	else
1061		retcode = sysfs_create_group(&intf->dev.kobj,
1062					     &capability_attr_grp);
1063
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1064	retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp);
1065
1066	retcode = usb_register_dev(intf, &usbtmc_class);
1067	if (retcode) {
1068		dev_err(&intf->dev, "Not able to get a minor"
1069			" (base %u, slice default): %d\n", USBTMC_MINOR_BASE,
1070			retcode);
1071		goto error_register;
1072	}
1073	dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor);
1074
1075	return 0;
1076
1077error_register:
1078	sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1079	sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
 
 
1080	kref_put(&data->kref, usbtmc_delete);
1081	return retcode;
1082}
1083
1084static void usbtmc_disconnect(struct usb_interface *intf)
1085{
1086	struct usbtmc_device_data *data;
1087
1088	dev_dbg(&intf->dev, "usbtmc_disconnect called\n");
1089
1090	data = usb_get_intfdata(intf);
1091	usb_deregister_dev(intf, &usbtmc_class);
1092	sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1093	sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
1094	mutex_lock(&data->io_mutex);
1095	data->zombie = 1;
 
1096	mutex_unlock(&data->io_mutex);
 
1097	kref_put(&data->kref, usbtmc_delete);
1098}
1099
1100static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message)
1101{
1102	/* this driver does not have pending URBs */
1103	return 0;
1104}
1105
1106static int usbtmc_resume(struct usb_interface *intf)
1107{
1108	return 0;
1109}
1110
1111static struct usb_driver usbtmc_driver = {
1112	.name		= "usbtmc",
1113	.id_table	= usbtmc_devices,
1114	.probe		= usbtmc_probe,
1115	.disconnect	= usbtmc_disconnect,
1116	.suspend	= usbtmc_suspend,
1117	.resume		= usbtmc_resume,
1118};
1119
1120static int __init usbtmc_init(void)
1121{
1122	int retcode;
1123
1124	retcode = usb_register(&usbtmc_driver);
1125	if (retcode)
1126		printk(KERN_ERR KBUILD_MODNAME": Unable to register driver\n");
1127	return retcode;
1128}
1129module_init(usbtmc_init);
1130
1131static void __exit usbtmc_exit(void)
1132{
1133	usb_deregister(&usbtmc_driver);
1134}
1135module_exit(usbtmc_exit);
1136
1137MODULE_LICENSE("GPL");
v4.17
   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 */
   9
  10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12#include <linux/module.h>
  13#include <linux/kernel.h>
  14#include <linux/fs.h>
  15#include <linux/uaccess.h>
  16#include <linux/kref.h>
  17#include <linux/slab.h>
  18#include <linux/poll.h>
  19#include <linux/mutex.h>
  20#include <linux/usb.h>
  21#include <linux/usb/tmc.h>
  22
  23
  24#define RIGOL			1
  25#define USBTMC_HEADER_SIZE	12
  26#define USBTMC_MINOR_BASE	176
  27
  28/*
  29 * Size of driver internal IO buffer. Must be multiple of 4 and at least as
  30 * large as wMaxPacketSize (which is usually 512 bytes).
  31 */
  32#define USBTMC_SIZE_IOBUFFER	2048
  33
  34/* Default USB timeout (in milliseconds) */
  35#define USBTMC_TIMEOUT		5000
  36
  37/*
  38 * Maximum number of read cycles to empty bulk in endpoint during CLEAR and
  39 * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
  40 * packet is never read.
  41 */
  42#define USBTMC_MAX_READS_TO_CLEAR_BULK_IN	100
  43
  44static const struct usb_device_id usbtmc_devices[] = {
  45	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), },
  46	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), },
  47	{ 0, } /* terminating entry */
  48};
  49MODULE_DEVICE_TABLE(usb, usbtmc_devices);
  50
  51/*
  52 * This structure is the capabilities for the device
  53 * See section 4.2.1.8 of the USBTMC specification,
  54 * and section 4.2.2 of the USBTMC usb488 subclass
  55 * specification for details.
  56 */
  57struct usbtmc_dev_capabilities {
  58	__u8 interface_capabilities;
  59	__u8 device_capabilities;
  60	__u8 usb488_interface_capabilities;
  61	__u8 usb488_device_capabilities;
  62};
  63
  64/* This structure holds private data for each USBTMC device. One copy is
  65 * allocated for each USBTMC device in the driver's probe function.
  66 */
  67struct usbtmc_device_data {
  68	const struct usb_device_id *id;
  69	struct usb_device *usb_dev;
  70	struct usb_interface *intf;
  71
  72	unsigned int bulk_in;
  73	unsigned int bulk_out;
  74
  75	u8 bTag;
  76	u8 bTag_last_write;	/* needed for abort */
  77	u8 bTag_last_read;	/* needed for abort */
  78
  79	/* data for interrupt in endpoint handling */
  80	u8             bNotify1;
  81	u8             bNotify2;
  82	u16            ifnum;
  83	u8             iin_bTag;
  84	u8            *iin_buffer;
  85	atomic_t       iin_data_valid;
  86	unsigned int   iin_ep;
  87	int            iin_ep_present;
  88	int            iin_interval;
  89	struct urb    *iin_urb;
  90	u16            iin_wMaxPacketSize;
  91	atomic_t       srq_asserted;
  92
  93	/* coalesced usb488_caps from usbtmc_dev_capabilities */
  94	__u8 usb488_caps;
  95
  96	u8 rigol_quirk;
  97
  98	/* attributes from the USB TMC spec for this device */
  99	u8 TermChar;
 100	bool TermCharEnabled;
 101	bool auto_abort;
 102
 103	bool zombie; /* fd of disconnected device */
 104
 105	struct usbtmc_dev_capabilities	capabilities;
 106	struct kref kref;
 107	struct mutex io_mutex;	/* only one i/o function running at a time */
 108	wait_queue_head_t waitq;
 109	struct fasync_struct *fasync;
 110};
 111#define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref)
 112
 113struct usbtmc_ID_rigol_quirk {
 114	__u16 idVendor;
 115	__u16 idProduct;
 116};
 117
 118static const struct usbtmc_ID_rigol_quirk usbtmc_id_quirk[] = {
 119	{ 0x1ab1, 0x0588 },
 120	{ 0x1ab1, 0x04b0 },
 121	{ 0, 0 }
 122};
 123
 124/* Forward declarations */
 125static struct usb_driver usbtmc_driver;
 126
 127static void usbtmc_delete(struct kref *kref)
 128{
 129	struct usbtmc_device_data *data = to_usbtmc_data(kref);
 130
 131	usb_put_dev(data->usb_dev);
 132	kfree(data);
 133}
 134
 135static int usbtmc_open(struct inode *inode, struct file *filp)
 136{
 137	struct usb_interface *intf;
 138	struct usbtmc_device_data *data;
 139	int retval = 0;
 140
 141	intf = usb_find_interface(&usbtmc_driver, iminor(inode));
 142	if (!intf) {
 143		pr_err("can not find device for minor %d", iminor(inode));
 144		return -ENODEV;
 
 
 145	}
 146
 147	data = usb_get_intfdata(intf);
 148	/* Protect reference to data from file structure until release */
 149	kref_get(&data->kref);
 150
 151	/* Store pointer in file structure's private data field */
 152	filp->private_data = data;
 153
 
 154	return retval;
 155}
 156
 157static int usbtmc_release(struct inode *inode, struct file *file)
 158{
 159	struct usbtmc_device_data *data = file->private_data;
 160
 161	kref_put(&data->kref, usbtmc_delete);
 162	return 0;
 163}
 164
 165static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data)
 166{
 167	u8 *buffer;
 168	struct device *dev;
 169	int rv;
 170	int n;
 171	int actual;
 172	struct usb_host_interface *current_setting;
 173	int max_size;
 174
 175	dev = &data->intf->dev;
 176	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 177	if (!buffer)
 178		return -ENOMEM;
 179
 180	rv = usb_control_msg(data->usb_dev,
 181			     usb_rcvctrlpipe(data->usb_dev, 0),
 182			     USBTMC_REQUEST_INITIATE_ABORT_BULK_IN,
 183			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 184			     data->bTag_last_read, data->bulk_in,
 185			     buffer, 2, USBTMC_TIMEOUT);
 186
 187	if (rv < 0) {
 188		dev_err(dev, "usb_control_msg returned %d\n", rv);
 189		goto exit;
 190	}
 191
 192	dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 193
 194	if (buffer[0] == USBTMC_STATUS_FAILED) {
 195		rv = 0;
 196		goto exit;
 197	}
 198
 199	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 200		dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n",
 201			buffer[0]);
 202		rv = -EPERM;
 203		goto exit;
 204	}
 205
 206	max_size = 0;
 207	current_setting = data->intf->cur_altsetting;
 208	for (n = 0; n < current_setting->desc.bNumEndpoints; n++)
 209		if (current_setting->endpoint[n].desc.bEndpointAddress ==
 210			data->bulk_in)
 211			max_size = usb_endpoint_maxp(&current_setting->endpoint[n].desc);
 
 212
 213	if (max_size == 0) {
 214		dev_err(dev, "Couldn't get wMaxPacketSize\n");
 215		rv = -EPERM;
 216		goto exit;
 217	}
 218
 219	dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size);
 220
 221	n = 0;
 222
 223	do {
 224		dev_dbg(dev, "Reading from bulk in EP\n");
 225
 226		rv = usb_bulk_msg(data->usb_dev,
 227				  usb_rcvbulkpipe(data->usb_dev,
 228						  data->bulk_in),
 229				  buffer, USBTMC_SIZE_IOBUFFER,
 230				  &actual, USBTMC_TIMEOUT);
 231
 232		n++;
 233
 234		if (rv < 0) {
 235			dev_err(dev, "usb_bulk_msg returned %d\n", rv);
 236			goto exit;
 237		}
 238	} while ((actual == max_size) &&
 239		 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 240
 241	if (actual == max_size) {
 242		dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 243			USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 244		rv = -EPERM;
 245		goto exit;
 246	}
 247
 248	n = 0;
 249
 250usbtmc_abort_bulk_in_status:
 251	rv = usb_control_msg(data->usb_dev,
 252			     usb_rcvctrlpipe(data->usb_dev, 0),
 253			     USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS,
 254			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 255			     0, data->bulk_in, buffer, 0x08,
 256			     USBTMC_TIMEOUT);
 257
 258	if (rv < 0) {
 259		dev_err(dev, "usb_control_msg returned %d\n", rv);
 260		goto exit;
 261	}
 262
 263	dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 264
 265	if (buffer[0] == USBTMC_STATUS_SUCCESS) {
 266		rv = 0;
 267		goto exit;
 268	}
 269
 270	if (buffer[0] != USBTMC_STATUS_PENDING) {
 271		dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 272		rv = -EPERM;
 273		goto exit;
 274	}
 275
 276	if (buffer[1] == 1)
 277		do {
 278			dev_dbg(dev, "Reading from bulk in EP\n");
 279
 280			rv = usb_bulk_msg(data->usb_dev,
 281					  usb_rcvbulkpipe(data->usb_dev,
 282							  data->bulk_in),
 283					  buffer, USBTMC_SIZE_IOBUFFER,
 284					  &actual, USBTMC_TIMEOUT);
 285
 286			n++;
 287
 288			if (rv < 0) {
 289				dev_err(dev, "usb_bulk_msg returned %d\n", rv);
 290				goto exit;
 291			}
 292		} while ((actual == max_size) &&
 293			 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 294
 295	if (actual == max_size) {
 296		dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 297			USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 298		rv = -EPERM;
 299		goto exit;
 300	}
 301
 302	goto usbtmc_abort_bulk_in_status;
 303
 304exit:
 305	kfree(buffer);
 306	return rv;
 307
 308}
 309
 310static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
 311{
 312	struct device *dev;
 313	u8 *buffer;
 314	int rv;
 315	int n;
 316
 317	dev = &data->intf->dev;
 318
 319	buffer = kmalloc(8, GFP_KERNEL);
 320	if (!buffer)
 321		return -ENOMEM;
 322
 323	rv = usb_control_msg(data->usb_dev,
 324			     usb_rcvctrlpipe(data->usb_dev, 0),
 325			     USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT,
 326			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 327			     data->bTag_last_write, data->bulk_out,
 328			     buffer, 2, USBTMC_TIMEOUT);
 329
 330	if (rv < 0) {
 331		dev_err(dev, "usb_control_msg returned %d\n", rv);
 332		goto exit;
 333	}
 334
 335	dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]);
 336
 337	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 338		dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n",
 339			buffer[0]);
 340		rv = -EPERM;
 341		goto exit;
 342	}
 343
 344	n = 0;
 345
 346usbtmc_abort_bulk_out_check_status:
 347	rv = usb_control_msg(data->usb_dev,
 348			     usb_rcvctrlpipe(data->usb_dev, 0),
 349			     USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS,
 350			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 351			     0, data->bulk_out, buffer, 0x08,
 352			     USBTMC_TIMEOUT);
 353	n++;
 354	if (rv < 0) {
 355		dev_err(dev, "usb_control_msg returned %d\n", rv);
 356		goto exit;
 357	}
 358
 359	dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]);
 360
 361	if (buffer[0] == USBTMC_STATUS_SUCCESS)
 362		goto usbtmc_abort_bulk_out_clear_halt;
 363
 364	if ((buffer[0] == USBTMC_STATUS_PENDING) &&
 365	    (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN))
 366		goto usbtmc_abort_bulk_out_check_status;
 367
 368	rv = -EPERM;
 369	goto exit;
 370
 371usbtmc_abort_bulk_out_clear_halt:
 372	rv = usb_clear_halt(data->usb_dev,
 373			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 374
 375	if (rv < 0) {
 376		dev_err(dev, "usb_control_msg returned %d\n", rv);
 377		goto exit;
 378	}
 379	rv = 0;
 380
 381exit:
 382	kfree(buffer);
 383	return rv;
 384}
 385
 386static int usbtmc488_ioctl_read_stb(struct usbtmc_device_data *data,
 387				void __user *arg)
 388{
 389	struct device *dev = &data->intf->dev;
 390	u8 *buffer;
 391	u8 tag;
 392	__u8 stb;
 393	int rv;
 394
 395	dev_dbg(dev, "Enter ioctl_read_stb iin_ep_present: %d\n",
 396		data->iin_ep_present);
 397
 398	buffer = kmalloc(8, GFP_KERNEL);
 399	if (!buffer)
 400		return -ENOMEM;
 401
 402	atomic_set(&data->iin_data_valid, 0);
 403
 404	/* must issue read_stb before using poll or select */
 405	atomic_set(&data->srq_asserted, 0);
 406
 407	rv = usb_control_msg(data->usb_dev,
 408			usb_rcvctrlpipe(data->usb_dev, 0),
 409			USBTMC488_REQUEST_READ_STATUS_BYTE,
 410			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 411			data->iin_bTag,
 412			data->ifnum,
 413			buffer, 0x03, USBTMC_TIMEOUT);
 414	if (rv < 0) {
 415		dev_err(dev, "stb usb_control_msg returned %d\n", rv);
 416		goto exit;
 417	}
 418
 419	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 420		dev_err(dev, "control status returned %x\n", buffer[0]);
 421		rv = -EIO;
 422		goto exit;
 423	}
 424
 425	if (data->iin_ep_present) {
 426		rv = wait_event_interruptible_timeout(
 427			data->waitq,
 428			atomic_read(&data->iin_data_valid) != 0,
 429			USBTMC_TIMEOUT);
 430		if (rv < 0) {
 431			dev_dbg(dev, "wait interrupted %d\n", rv);
 432			goto exit;
 433		}
 434
 435		if (rv == 0) {
 436			dev_dbg(dev, "wait timed out\n");
 437			rv = -ETIME;
 438			goto exit;
 439		}
 440
 441		tag = data->bNotify1 & 0x7f;
 442		if (tag != data->iin_bTag) {
 443			dev_err(dev, "expected bTag %x got %x\n",
 444				data->iin_bTag, tag);
 445		}
 446
 447		stb = data->bNotify2;
 448	} else {
 449		stb = buffer[2];
 450	}
 451
 452	rv = copy_to_user(arg, &stb, sizeof(stb));
 453	if (rv)
 454		rv = -EFAULT;
 455
 456 exit:
 457	/* bump interrupt bTag */
 458	data->iin_bTag += 1;
 459	if (data->iin_bTag > 127)
 460		/* 1 is for SRQ see USBTMC-USB488 subclass spec section 4.3.1 */
 461		data->iin_bTag = 2;
 462
 463	kfree(buffer);
 464	return rv;
 465}
 466
 467static int usbtmc488_ioctl_simple(struct usbtmc_device_data *data,
 468				void __user *arg, unsigned int cmd)
 469{
 470	struct device *dev = &data->intf->dev;
 471	__u8 val;
 472	u8 *buffer;
 473	u16 wValue;
 474	int rv;
 475
 476	if (!(data->usb488_caps & USBTMC488_CAPABILITY_SIMPLE))
 477		return -EINVAL;
 478
 479	buffer = kmalloc(8, GFP_KERNEL);
 480	if (!buffer)
 481		return -ENOMEM;
 482
 483	if (cmd == USBTMC488_REQUEST_REN_CONTROL) {
 484		rv = copy_from_user(&val, arg, sizeof(val));
 485		if (rv) {
 486			rv = -EFAULT;
 487			goto exit;
 488		}
 489		wValue = val ? 1 : 0;
 490	} else {
 491		wValue = 0;
 492	}
 493
 494	rv = usb_control_msg(data->usb_dev,
 495			usb_rcvctrlpipe(data->usb_dev, 0),
 496			cmd,
 497			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 498			wValue,
 499			data->ifnum,
 500			buffer, 0x01, USBTMC_TIMEOUT);
 501	if (rv < 0) {
 502		dev_err(dev, "simple usb_control_msg failed %d\n", rv);
 503		goto exit;
 504	} else if (rv != 1) {
 505		dev_warn(dev, "simple usb_control_msg returned %d\n", rv);
 506		rv = -EIO;
 507		goto exit;
 508	}
 509
 510	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 511		dev_err(dev, "simple control status returned %x\n", buffer[0]);
 512		rv = -EIO;
 513		goto exit;
 514	}
 515	rv = 0;
 516
 517 exit:
 518	kfree(buffer);
 519	return rv;
 520}
 521
 522/*
 523 * Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-OUT endpoint.
 524 * @transfer_size: number of bytes to request from the device.
 525 *
 526 * See the USBTMC specification, Table 4.
 527 *
 528 * Also updates bTag_last_write.
 529 */
 530static int send_request_dev_dep_msg_in(struct usbtmc_device_data *data, size_t transfer_size)
 531{
 532	int retval;
 533	u8 *buffer;
 534	int actual;
 535
 536	buffer = kmalloc(USBTMC_HEADER_SIZE, GFP_KERNEL);
 537	if (!buffer)
 538		return -ENOMEM;
 539	/* Setup IO buffer for REQUEST_DEV_DEP_MSG_IN message
 540	 * Refer to class specs for details
 541	 */
 542	buffer[0] = 2;
 543	buffer[1] = data->bTag;
 544	buffer[2] = ~data->bTag;
 545	buffer[3] = 0; /* Reserved */
 546	buffer[4] = transfer_size >> 0;
 547	buffer[5] = transfer_size >> 8;
 548	buffer[6] = transfer_size >> 16;
 549	buffer[7] = transfer_size >> 24;
 550	buffer[8] = data->TermCharEnabled * 2;
 551	/* Use term character? */
 552	buffer[9] = data->TermChar;
 553	buffer[10] = 0; /* Reserved */
 554	buffer[11] = 0; /* Reserved */
 555
 556	/* Send bulk URB */
 557	retval = usb_bulk_msg(data->usb_dev,
 558			      usb_sndbulkpipe(data->usb_dev,
 559					      data->bulk_out),
 560			      buffer, USBTMC_HEADER_SIZE, &actual, USBTMC_TIMEOUT);
 561
 562	/* Store bTag (in case we need to abort) */
 563	data->bTag_last_write = data->bTag;
 564
 565	/* Increment bTag -- and increment again if zero */
 566	data->bTag++;
 567	if (!data->bTag)
 568		data->bTag++;
 569
 570	kfree(buffer);
 571	if (retval < 0) {
 572		dev_err(&data->intf->dev, "usb_bulk_msg in send_request_dev_dep_msg_in() returned %d\n", retval);
 573		return retval;
 574	}
 575
 576	return 0;
 577}
 578
 579static ssize_t usbtmc_read(struct file *filp, char __user *buf,
 580			   size_t count, loff_t *f_pos)
 581{
 582	struct usbtmc_device_data *data;
 583	struct device *dev;
 584	u32 n_characters;
 585	u8 *buffer;
 586	int actual;
 587	size_t done;
 588	size_t remaining;
 589	int retval;
 590	size_t this_part;
 591
 592	/* Get pointer to private data structure */
 593	data = filp->private_data;
 594	dev = &data->intf->dev;
 595
 596	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 597	if (!buffer)
 598		return -ENOMEM;
 599
 600	mutex_lock(&data->io_mutex);
 601	if (data->zombie) {
 602		retval = -ENODEV;
 603		goto exit;
 604	}
 605
 606	if (data->rigol_quirk) {
 607		dev_dbg(dev, "usb_bulk_msg_in: count(%zu)\n", count);
 608
 609		retval = send_request_dev_dep_msg_in(data, count);
 
 
 
 
 610
 611		if (retval < 0) {
 612			if (data->auto_abort)
 613				usbtmc_ioctl_abort_bulk_out(data);
 614			goto exit;
 615		}
 616	}
 
 
 
 
 
 
 
 
 
 
 617
 618	/* Loop until we have fetched everything we requested */
 619	remaining = count;
 620	this_part = remaining;
 621	done = 0;
 
 622
 623	while (remaining > 0) {
 624		if (!data->rigol_quirk) {
 625			dev_dbg(dev, "usb_bulk_msg_in: remaining(%zu), count(%zu)\n", remaining, count);
 626
 627			if (remaining > USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE - 3)
 628				this_part = USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE - 3;
 629			else
 630				this_part = remaining;
 631
 632			retval = send_request_dev_dep_msg_in(data, this_part);
 633			if (retval < 0) {
 634			dev_err(dev, "usb_bulk_msg returned %d\n", retval);
 635				if (data->auto_abort)
 636					usbtmc_ioctl_abort_bulk_out(data);
 637				goto exit;
 638			}
 639		}
 640
 641		/* Send bulk URB */
 642		retval = usb_bulk_msg(data->usb_dev,
 643				      usb_rcvbulkpipe(data->usb_dev,
 644						      data->bulk_in),
 645				      buffer, USBTMC_SIZE_IOBUFFER, &actual,
 646				      USBTMC_TIMEOUT);
 647
 648		dev_dbg(dev, "usb_bulk_msg: retval(%u), done(%zu), remaining(%zu), actual(%d)\n", retval, done, remaining, actual);
 649
 650		/* Store bTag (in case we need to abort) */
 651		data->bTag_last_read = data->bTag;
 652
 653		if (retval < 0) {
 654			dev_dbg(dev, "Unable to read data, error %d\n", retval);
 655			if (data->auto_abort)
 656				usbtmc_ioctl_abort_bulk_in(data);
 657			goto exit;
 658		}
 659
 660		/* Parse header in first packet */
 661		if ((done == 0) || !data->rigol_quirk) {
 662			/* Sanity checks for the header */
 663			if (actual < USBTMC_HEADER_SIZE) {
 664				dev_err(dev, "Device sent too small first packet: %u < %u\n", actual, USBTMC_HEADER_SIZE);
 665				if (data->auto_abort)
 666					usbtmc_ioctl_abort_bulk_in(data);
 667				goto exit;
 668			}
 
 
 669
 670			if (buffer[0] != 2) {
 671				dev_err(dev, "Device sent reply with wrong MsgID: %u != 2\n", buffer[0]);
 672				if (data->auto_abort)
 673					usbtmc_ioctl_abort_bulk_in(data);
 674				goto exit;
 675			}
 676
 677			if (buffer[1] != data->bTag_last_write) {
 678				dev_err(dev, "Device sent reply with wrong bTag: %u != %u\n", buffer[1], data->bTag_last_write);
 679				if (data->auto_abort)
 680					usbtmc_ioctl_abort_bulk_in(data);
 681				goto exit;
 682			}
 683
 684			/* How many characters did the instrument send? */
 685			n_characters = buffer[4] +
 686				       (buffer[5] << 8) +
 687				       (buffer[6] << 16) +
 688				       (buffer[7] << 24);
 689
 690			if (n_characters > this_part) {
 691				dev_err(dev, "Device wants to return more data than requested: %u > %zu\n", n_characters, count);
 692				if (data->auto_abort)
 693					usbtmc_ioctl_abort_bulk_in(data);
 694				goto exit;
 695			}
 696
 697			/* Remove the USBTMC header */
 698			actual -= USBTMC_HEADER_SIZE;
 699
 700			/* Check if the message is smaller than requested */
 701			if (data->rigol_quirk) {
 702				if (remaining > n_characters)
 703					remaining = n_characters;
 704				/* Remove padding if it exists */
 705				if (actual > remaining)
 706					actual = remaining;
 707			}
 708			else {
 709				if (this_part > n_characters)
 710					this_part = n_characters;
 711				/* Remove padding if it exists */
 712				if (actual > this_part)
 713					actual = this_part;
 714			}
 715
 716			dev_dbg(dev, "Bulk-IN header: N_characters(%u), bTransAttr(%u)\n", n_characters, buffer[8]);
 717
 718			remaining -= actual;
 719
 720			/* Terminate if end-of-message bit received from device */
 721			if ((buffer[8] & 0x01) && (actual >= n_characters))
 722				remaining = 0;
 723
 724			dev_dbg(dev, "Bulk-IN header: remaining(%zu), buf(%p), buffer(%p) done(%zu)\n", remaining,buf,buffer,done);
 725
 726
 727			/* Copy buffer to user space */
 728			if (copy_to_user(buf + done, &buffer[USBTMC_HEADER_SIZE], actual)) {
 729				/* There must have been an addressing problem */
 730				retval = -EFAULT;
 731				goto exit;
 732			}
 733			done += actual;
 734		}
 735		else  {
 736			if (actual > remaining)
 737				actual = remaining;
 738
 739			remaining -= actual;
 740
 741			dev_dbg(dev, "Bulk-IN header cont: actual(%u), done(%zu), remaining(%zu), buf(%p), buffer(%p)\n", actual, done, remaining,buf,buffer);
 742
 743			/* Copy buffer to user space */
 744			if (copy_to_user(buf + done, buffer, actual)) {
 745				/* There must have been an addressing problem */
 746				retval = -EFAULT;
 747				goto exit;
 748			}
 749			done += actual;
 750		}
 751	}
 752
 753	/* Update file position value */
 754	*f_pos = *f_pos + done;
 755	retval = done;
 756
 757exit:
 758	mutex_unlock(&data->io_mutex);
 759	kfree(buffer);
 760	return retval;
 761}
 762
 763static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
 764			    size_t count, loff_t *f_pos)
 765{
 766	struct usbtmc_device_data *data;
 767	u8 *buffer;
 768	int retval;
 769	int actual;
 770	unsigned long int n_bytes;
 771	int remaining;
 772	int done;
 773	int this_part;
 774
 775	data = filp->private_data;
 776
 777	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 778	if (!buffer)
 779		return -ENOMEM;
 780
 781	mutex_lock(&data->io_mutex);
 782	if (data->zombie) {
 783		retval = -ENODEV;
 784		goto exit;
 785	}
 786
 787	remaining = count;
 788	done = 0;
 789
 790	while (remaining > 0) {
 791		if (remaining > USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE) {
 792			this_part = USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE;
 793			buffer[8] = 0;
 794		} else {
 795			this_part = remaining;
 796			buffer[8] = 1;
 797		}
 798
 799		/* Setup IO buffer for DEV_DEP_MSG_OUT message */
 800		buffer[0] = 1;
 801		buffer[1] = data->bTag;
 802		buffer[2] = ~data->bTag;
 803		buffer[3] = 0; /* Reserved */
 804		buffer[4] = this_part >> 0;
 805		buffer[5] = this_part >> 8;
 806		buffer[6] = this_part >> 16;
 807		buffer[7] = this_part >> 24;
 808		/* buffer[8] is set above... */
 809		buffer[9] = 0; /* Reserved */
 810		buffer[10] = 0; /* Reserved */
 811		buffer[11] = 0; /* Reserved */
 812
 813		if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf + done, this_part)) {
 814			retval = -EFAULT;
 815			goto exit;
 816		}
 817
 818		n_bytes = roundup(USBTMC_HEADER_SIZE + this_part, 4);
 819		memset(buffer + USBTMC_HEADER_SIZE + this_part, 0, n_bytes - (USBTMC_HEADER_SIZE + this_part));
 820
 821		do {
 822			retval = usb_bulk_msg(data->usb_dev,
 823					      usb_sndbulkpipe(data->usb_dev,
 824							      data->bulk_out),
 825					      buffer, n_bytes,
 826					      &actual, USBTMC_TIMEOUT);
 827			if (retval != 0)
 828				break;
 829			n_bytes -= actual;
 830		} while (n_bytes);
 831
 832		data->bTag_last_write = data->bTag;
 833		data->bTag++;
 834
 835		if (!data->bTag)
 836			data->bTag++;
 837
 838		if (retval < 0) {
 839			dev_err(&data->intf->dev,
 840				"Unable to send data, error %d\n", retval);
 841			if (data->auto_abort)
 842				usbtmc_ioctl_abort_bulk_out(data);
 843			goto exit;
 844		}
 845
 846		remaining -= this_part;
 847		done += this_part;
 848	}
 849
 850	retval = count;
 851exit:
 852	mutex_unlock(&data->io_mutex);
 853	kfree(buffer);
 854	return retval;
 855}
 856
 857static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
 858{
 859	struct usb_host_interface *current_setting;
 860	struct usb_endpoint_descriptor *desc;
 861	struct device *dev;
 862	u8 *buffer;
 863	int rv;
 864	int n;
 865	int actual = 0;
 866	int max_size;
 867
 868	dev = &data->intf->dev;
 869
 870	dev_dbg(dev, "Sending INITIATE_CLEAR request\n");
 871
 872	buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 873	if (!buffer)
 874		return -ENOMEM;
 875
 876	rv = usb_control_msg(data->usb_dev,
 877			     usb_rcvctrlpipe(data->usb_dev, 0),
 878			     USBTMC_REQUEST_INITIATE_CLEAR,
 879			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 880			     0, 0, buffer, 1, USBTMC_TIMEOUT);
 881	if (rv < 0) {
 882		dev_err(dev, "usb_control_msg returned %d\n", rv);
 883		goto exit;
 884	}
 885
 886	dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
 887
 888	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 889		dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
 890		rv = -EPERM;
 891		goto exit;
 892	}
 893
 894	max_size = 0;
 895	current_setting = data->intf->cur_altsetting;
 896	for (n = 0; n < current_setting->desc.bNumEndpoints; n++) {
 897		desc = &current_setting->endpoint[n].desc;
 898		if (desc->bEndpointAddress == data->bulk_in)
 899			max_size = usb_endpoint_maxp(desc);
 900	}
 901
 902	if (max_size == 0) {
 903		dev_err(dev, "Couldn't get wMaxPacketSize\n");
 904		rv = -EPERM;
 905		goto exit;
 906	}
 907
 908	dev_dbg(dev, "wMaxPacketSize is %d\n", max_size);
 909
 910	n = 0;
 911
 912usbtmc_clear_check_status:
 913
 914	dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n");
 915
 916	rv = usb_control_msg(data->usb_dev,
 917			     usb_rcvctrlpipe(data->usb_dev, 0),
 918			     USBTMC_REQUEST_CHECK_CLEAR_STATUS,
 919			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 920			     0, 0, buffer, 2, USBTMC_TIMEOUT);
 921	if (rv < 0) {
 922		dev_err(dev, "usb_control_msg returned %d\n", rv);
 923		goto exit;
 924	}
 925
 926	dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
 927
 928	if (buffer[0] == USBTMC_STATUS_SUCCESS)
 929		goto usbtmc_clear_bulk_out_halt;
 930
 931	if (buffer[0] != USBTMC_STATUS_PENDING) {
 932		dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
 933		rv = -EPERM;
 934		goto exit;
 935	}
 936
 937	if (buffer[1] == 1)
 938		do {
 939			dev_dbg(dev, "Reading from bulk in EP\n");
 940
 941			rv = usb_bulk_msg(data->usb_dev,
 942					  usb_rcvbulkpipe(data->usb_dev,
 943							  data->bulk_in),
 944					  buffer, USBTMC_SIZE_IOBUFFER,
 945					  &actual, USBTMC_TIMEOUT);
 946			n++;
 947
 948			if (rv < 0) {
 949				dev_err(dev, "usb_control_msg returned %d\n",
 950					rv);
 951				goto exit;
 952			}
 953		} while ((actual == max_size) &&
 954			  (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 955
 956	if (actual == max_size) {
 957		dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 958			USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 959		rv = -EPERM;
 960		goto exit;
 961	}
 962
 963	goto usbtmc_clear_check_status;
 964
 965usbtmc_clear_bulk_out_halt:
 966
 967	rv = usb_clear_halt(data->usb_dev,
 968			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 969	if (rv < 0) {
 970		dev_err(dev, "usb_control_msg returned %d\n", rv);
 971		goto exit;
 972	}
 973	rv = 0;
 974
 975exit:
 976	kfree(buffer);
 977	return rv;
 978}
 979
 980static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
 981{
 
 982	int rv;
 983
 
 
 
 
 984	rv = usb_clear_halt(data->usb_dev,
 985			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 986
 987	if (rv < 0) {
 988		dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
 989			rv);
 990		return rv;
 991	}
 992	return 0;
 
 
 
 
 993}
 994
 995static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
 996{
 
 997	int rv;
 998
 
 
 
 
 999	rv = usb_clear_halt(data->usb_dev,
1000			    usb_rcvbulkpipe(data->usb_dev, data->bulk_in));
1001
1002	if (rv < 0) {
1003		dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
1004			rv);
1005		return rv;
1006	}
1007	return 0;
 
 
 
 
1008}
1009
1010static int get_capabilities(struct usbtmc_device_data *data)
1011{
1012	struct device *dev = &data->usb_dev->dev;
1013	char *buffer;
1014	int rv = 0;
1015
1016	buffer = kmalloc(0x18, GFP_KERNEL);
1017	if (!buffer)
1018		return -ENOMEM;
1019
1020	rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0),
1021			     USBTMC_REQUEST_GET_CAPABILITIES,
1022			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1023			     0, 0, buffer, 0x18, USBTMC_TIMEOUT);
1024	if (rv < 0) {
1025		dev_err(dev, "usb_control_msg returned %d\n", rv);
1026		goto err_out;
1027	}
1028
1029	dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
1030	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1031		dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
1032		rv = -EPERM;
1033		goto err_out;
1034	}
1035	dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
1036	dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
1037	dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
1038	dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
1039
1040	data->capabilities.interface_capabilities = buffer[4];
1041	data->capabilities.device_capabilities = buffer[5];
1042	data->capabilities.usb488_interface_capabilities = buffer[14];
1043	data->capabilities.usb488_device_capabilities = buffer[15];
1044	data->usb488_caps = (buffer[14] & 0x07) | ((buffer[15] & 0x0f) << 4);
1045	rv = 0;
1046
1047err_out:
1048	kfree(buffer);
1049	return rv;
1050}
1051
1052#define capability_attribute(name)					\
1053static ssize_t name##_show(struct device *dev,				\
1054			   struct device_attribute *attr, char *buf)	\
1055{									\
1056	struct usb_interface *intf = to_usb_interface(dev);		\
1057	struct usbtmc_device_data *data = usb_get_intfdata(intf);	\
1058									\
1059	return sprintf(buf, "%d\n", data->capabilities.name);		\
1060}									\
1061static DEVICE_ATTR_RO(name)
1062
1063capability_attribute(interface_capabilities);
1064capability_attribute(device_capabilities);
1065capability_attribute(usb488_interface_capabilities);
1066capability_attribute(usb488_device_capabilities);
1067
1068static struct attribute *capability_attrs[] = {
1069	&dev_attr_interface_capabilities.attr,
1070	&dev_attr_device_capabilities.attr,
1071	&dev_attr_usb488_interface_capabilities.attr,
1072	&dev_attr_usb488_device_capabilities.attr,
1073	NULL,
1074};
1075
1076static const struct attribute_group capability_attr_grp = {
1077	.attrs = capability_attrs,
1078};
1079
1080static ssize_t TermChar_show(struct device *dev,
1081			     struct device_attribute *attr, char *buf)
1082{
1083	struct usb_interface *intf = to_usb_interface(dev);
1084	struct usbtmc_device_data *data = usb_get_intfdata(intf);
1085
1086	return sprintf(buf, "%c\n", data->TermChar);
1087}
1088
1089static ssize_t TermChar_store(struct device *dev,
1090			      struct device_attribute *attr,
1091			      const char *buf, size_t count)
1092{
1093	struct usb_interface *intf = to_usb_interface(dev);
1094	struct usbtmc_device_data *data = usb_get_intfdata(intf);
1095
1096	if (count < 1)
1097		return -EINVAL;
1098	data->TermChar = buf[0];
1099	return count;
1100}
1101static DEVICE_ATTR_RW(TermChar);
1102
1103#define data_attribute(name)						\
1104static ssize_t name##_show(struct device *dev,				\
1105			   struct device_attribute *attr, char *buf)	\
1106{									\
1107	struct usb_interface *intf = to_usb_interface(dev);		\
1108	struct usbtmc_device_data *data = usb_get_intfdata(intf);	\
1109									\
1110	return sprintf(buf, "%d\n", data->name);			\
1111}									\
1112static ssize_t name##_store(struct device *dev,				\
1113			    struct device_attribute *attr,		\
1114			    const char *buf, size_t count)		\
1115{									\
1116	struct usb_interface *intf = to_usb_interface(dev);		\
1117	struct usbtmc_device_data *data = usb_get_intfdata(intf);	\
1118	ssize_t result;							\
1119	unsigned val;							\
1120									\
1121	result = sscanf(buf, "%u\n", &val);				\
1122	if (result != 1)						\
1123		result = -EINVAL;					\
1124	data->name = val;						\
1125	if (result < 0)							\
1126		return result;						\
1127	else								\
1128		return count;						\
1129}									\
1130static DEVICE_ATTR_RW(name)
1131
1132data_attribute(TermCharEnabled);
1133data_attribute(auto_abort);
1134
1135static struct attribute *data_attrs[] = {
1136	&dev_attr_TermChar.attr,
1137	&dev_attr_TermCharEnabled.attr,
1138	&dev_attr_auto_abort.attr,
1139	NULL,
1140};
1141
1142static const struct attribute_group data_attr_grp = {
1143	.attrs = data_attrs,
1144};
1145
1146static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data)
1147{
1148	struct device *dev;
1149	u8 *buffer;
1150	int rv;
1151
1152	dev = &data->intf->dev;
1153
1154	buffer = kmalloc(2, GFP_KERNEL);
1155	if (!buffer)
1156		return -ENOMEM;
1157
1158	rv = usb_control_msg(data->usb_dev,
1159			     usb_rcvctrlpipe(data->usb_dev, 0),
1160			     USBTMC_REQUEST_INDICATOR_PULSE,
1161			     USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1162			     0, 0, buffer, 0x01, USBTMC_TIMEOUT);
1163
1164	if (rv < 0) {
1165		dev_err(dev, "usb_control_msg returned %d\n", rv);
1166		goto exit;
1167	}
1168
1169	dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
1170
1171	if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1172		dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
1173		rv = -EPERM;
1174		goto exit;
1175	}
1176	rv = 0;
1177
1178exit:
1179	kfree(buffer);
1180	return rv;
1181}
1182
1183static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1184{
1185	struct usbtmc_device_data *data;
1186	int retval = -EBADRQC;
1187
1188	data = file->private_data;
1189	mutex_lock(&data->io_mutex);
1190	if (data->zombie) {
1191		retval = -ENODEV;
1192		goto skip_io_on_zombie;
1193	}
1194
1195	switch (cmd) {
1196	case USBTMC_IOCTL_CLEAR_OUT_HALT:
1197		retval = usbtmc_ioctl_clear_out_halt(data);
1198		break;
1199
1200	case USBTMC_IOCTL_CLEAR_IN_HALT:
1201		retval = usbtmc_ioctl_clear_in_halt(data);
1202		break;
1203
1204	case USBTMC_IOCTL_INDICATOR_PULSE:
1205		retval = usbtmc_ioctl_indicator_pulse(data);
1206		break;
1207
1208	case USBTMC_IOCTL_CLEAR:
1209		retval = usbtmc_ioctl_clear(data);
1210		break;
1211
1212	case USBTMC_IOCTL_ABORT_BULK_OUT:
1213		retval = usbtmc_ioctl_abort_bulk_out(data);
1214		break;
1215
1216	case USBTMC_IOCTL_ABORT_BULK_IN:
1217		retval = usbtmc_ioctl_abort_bulk_in(data);
1218		break;
1219
1220	case USBTMC488_IOCTL_GET_CAPS:
1221		retval = copy_to_user((void __user *)arg,
1222				&data->usb488_caps,
1223				sizeof(data->usb488_caps));
1224		if (retval)
1225			retval = -EFAULT;
1226		break;
1227
1228	case USBTMC488_IOCTL_READ_STB:
1229		retval = usbtmc488_ioctl_read_stb(data, (void __user *)arg);
1230		break;
1231
1232	case USBTMC488_IOCTL_REN_CONTROL:
1233		retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
1234						USBTMC488_REQUEST_REN_CONTROL);
1235		break;
1236
1237	case USBTMC488_IOCTL_GOTO_LOCAL:
1238		retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
1239						USBTMC488_REQUEST_GOTO_LOCAL);
1240		break;
1241
1242	case USBTMC488_IOCTL_LOCAL_LOCKOUT:
1243		retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
1244						USBTMC488_REQUEST_LOCAL_LOCKOUT);
1245		break;
1246	}
1247
1248skip_io_on_zombie:
1249	mutex_unlock(&data->io_mutex);
1250	return retval;
1251}
1252
1253static int usbtmc_fasync(int fd, struct file *file, int on)
1254{
1255	struct usbtmc_device_data *data = file->private_data;
1256
1257	return fasync_helper(fd, file, on, &data->fasync);
1258}
1259
1260static __poll_t usbtmc_poll(struct file *file, poll_table *wait)
1261{
1262	struct usbtmc_device_data *data = file->private_data;
1263	__poll_t mask;
1264
1265	mutex_lock(&data->io_mutex);
1266
1267	if (data->zombie) {
1268		mask = EPOLLHUP | EPOLLERR;
1269		goto no_poll;
1270	}
1271
1272	poll_wait(file, &data->waitq, wait);
1273
1274	mask = (atomic_read(&data->srq_asserted)) ? EPOLLIN | EPOLLRDNORM : 0;
1275
1276no_poll:
1277	mutex_unlock(&data->io_mutex);
1278	return mask;
1279}
1280
1281static const struct file_operations fops = {
1282	.owner		= THIS_MODULE,
1283	.read		= usbtmc_read,
1284	.write		= usbtmc_write,
1285	.open		= usbtmc_open,
1286	.release	= usbtmc_release,
1287	.unlocked_ioctl	= usbtmc_ioctl,
1288	.fasync         = usbtmc_fasync,
1289	.poll           = usbtmc_poll,
1290	.llseek		= default_llseek,
1291};
1292
1293static struct usb_class_driver usbtmc_class = {
1294	.name =		"usbtmc%d",
1295	.fops =		&fops,
1296	.minor_base =	USBTMC_MINOR_BASE,
1297};
1298
1299static void usbtmc_interrupt(struct urb *urb)
1300{
1301	struct usbtmc_device_data *data = urb->context;
1302	struct device *dev = &data->intf->dev;
1303	int status = urb->status;
1304	int rv;
1305
1306	dev_dbg(&data->intf->dev, "int status: %d len %d\n",
1307		status, urb->actual_length);
1308
1309	switch (status) {
1310	case 0: /* SUCCESS */
1311		/* check for valid STB notification */
1312		if (data->iin_buffer[0] > 0x81) {
1313			data->bNotify1 = data->iin_buffer[0];
1314			data->bNotify2 = data->iin_buffer[1];
1315			atomic_set(&data->iin_data_valid, 1);
1316			wake_up_interruptible(&data->waitq);
1317			goto exit;
1318		}
1319		/* check for SRQ notification */
1320		if (data->iin_buffer[0] == 0x81) {
1321			if (data->fasync)
1322				kill_fasync(&data->fasync,
1323					SIGIO, POLL_IN);
1324
1325			atomic_set(&data->srq_asserted, 1);
1326			wake_up_interruptible(&data->waitq);
1327			goto exit;
1328		}
1329		dev_warn(dev, "invalid notification: %x\n", data->iin_buffer[0]);
1330		break;
1331	case -EOVERFLOW:
1332		dev_err(dev, "overflow with length %d, actual length is %d\n",
1333			data->iin_wMaxPacketSize, urb->actual_length);
1334		/* fall through */
1335	case -ECONNRESET:
1336	case -ENOENT:
1337	case -ESHUTDOWN:
1338	case -EILSEQ:
1339	case -ETIME:
1340		/* urb terminated, clean up */
1341		dev_dbg(dev, "urb terminated, status: %d\n", status);
1342		return;
1343	default:
1344		dev_err(dev, "unknown status received: %d\n", status);
1345	}
1346exit:
1347	rv = usb_submit_urb(urb, GFP_ATOMIC);
1348	if (rv)
1349		dev_err(dev, "usb_submit_urb failed: %d\n", rv);
1350}
1351
1352static void usbtmc_free_int(struct usbtmc_device_data *data)
1353{
1354	if (!data->iin_ep_present || !data->iin_urb)
1355		return;
1356	usb_kill_urb(data->iin_urb);
1357	kfree(data->iin_buffer);
1358	usb_free_urb(data->iin_urb);
1359	kref_put(&data->kref, usbtmc_delete);
1360}
1361
1362static int usbtmc_probe(struct usb_interface *intf,
1363			const struct usb_device_id *id)
1364{
1365	struct usbtmc_device_data *data;
1366	struct usb_host_interface *iface_desc;
1367	struct usb_endpoint_descriptor *bulk_in, *bulk_out, *int_in;
1368	int n;
1369	int retcode;
1370
1371	dev_dbg(&intf->dev, "%s called\n", __func__);
1372
1373	data = kzalloc(sizeof(*data), GFP_KERNEL);
1374	if (!data)
 
1375		return -ENOMEM;
 
1376
1377	data->intf = intf;
1378	data->id = id;
1379	data->usb_dev = usb_get_dev(interface_to_usbdev(intf));
1380	usb_set_intfdata(intf, data);
1381	kref_init(&data->kref);
1382	mutex_init(&data->io_mutex);
1383	init_waitqueue_head(&data->waitq);
1384	atomic_set(&data->iin_data_valid, 0);
1385	atomic_set(&data->srq_asserted, 0);
1386	data->zombie = 0;
1387
1388	/* Determine if it is a Rigol or not */
1389	data->rigol_quirk = 0;
1390	dev_dbg(&intf->dev, "Trying to find if device Vendor 0x%04X Product 0x%04X has the RIGOL quirk\n",
1391		le16_to_cpu(data->usb_dev->descriptor.idVendor),
1392		le16_to_cpu(data->usb_dev->descriptor.idProduct));
1393	for(n = 0; usbtmc_id_quirk[n].idVendor > 0; n++) {
1394		if ((usbtmc_id_quirk[n].idVendor == le16_to_cpu(data->usb_dev->descriptor.idVendor)) &&
1395		    (usbtmc_id_quirk[n].idProduct == le16_to_cpu(data->usb_dev->descriptor.idProduct))) {
1396			dev_dbg(&intf->dev, "Setting this device as having the RIGOL quirk\n");
1397			data->rigol_quirk = 1;
1398			break;
1399		}
1400	}
1401
1402	/* Initialize USBTMC bTag and other fields */
1403	data->bTag	= 1;
1404	data->TermCharEnabled = 0;
1405	data->TermChar = '\n';
1406	/*  2 <= bTag <= 127   USBTMC-USB488 subclass specification 4.3.1 */
1407	data->iin_bTag = 2;
1408
1409	/* USBTMC devices have only one setting, so use that */
1410	iface_desc = data->intf->cur_altsetting;
1411	data->ifnum = iface_desc->desc.bInterfaceNumber;
1412
1413	/* Find bulk endpoints */
1414	retcode = usb_find_common_endpoints(iface_desc,
1415			&bulk_in, &bulk_out, NULL, NULL);
1416	if (retcode) {
1417		dev_err(&intf->dev, "bulk endpoints not found\n");
1418		goto err_put;
 
 
 
 
1419	}
1420
1421	data->bulk_in = bulk_in->bEndpointAddress;
1422	dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n", data->bulk_in);
1423
1424	data->bulk_out = bulk_out->bEndpointAddress;
1425	dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n", data->bulk_out);
1426
1427	/* Find int endpoint */
1428	retcode = usb_find_int_in_endpoint(iface_desc, &int_in);
1429	if (!retcode) {
1430		data->iin_ep_present = 1;
1431		data->iin_ep = int_in->bEndpointAddress;
1432		data->iin_wMaxPacketSize = usb_endpoint_maxp(int_in);
1433		data->iin_interval = int_in->bInterval;
1434		dev_dbg(&intf->dev, "Found Int in endpoint at %u\n",
1435				data->iin_ep);
1436	}
1437
1438	retcode = get_capabilities(data);
1439	if (retcode)
1440		dev_err(&intf->dev, "can't read capabilities\n");
1441	else
1442		retcode = sysfs_create_group(&intf->dev.kobj,
1443					     &capability_attr_grp);
1444
1445	if (data->iin_ep_present) {
1446		/* allocate int urb */
1447		data->iin_urb = usb_alloc_urb(0, GFP_KERNEL);
1448		if (!data->iin_urb) {
1449			retcode = -ENOMEM;
1450			goto error_register;
1451		}
1452
1453		/* Protect interrupt in endpoint data until iin_urb is freed */
1454		kref_get(&data->kref);
1455
1456		/* allocate buffer for interrupt in */
1457		data->iin_buffer = kmalloc(data->iin_wMaxPacketSize,
1458					GFP_KERNEL);
1459		if (!data->iin_buffer) {
1460			retcode = -ENOMEM;
1461			goto error_register;
1462		}
1463
1464		/* fill interrupt urb */
1465		usb_fill_int_urb(data->iin_urb, data->usb_dev,
1466				usb_rcvintpipe(data->usb_dev, data->iin_ep),
1467				data->iin_buffer, data->iin_wMaxPacketSize,
1468				usbtmc_interrupt,
1469				data, data->iin_interval);
1470
1471		retcode = usb_submit_urb(data->iin_urb, GFP_KERNEL);
1472		if (retcode) {
1473			dev_err(&intf->dev, "Failed to submit iin_urb\n");
1474			goto error_register;
1475		}
1476	}
1477
1478	retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp);
1479
1480	retcode = usb_register_dev(intf, &usbtmc_class);
1481	if (retcode) {
1482		dev_err(&intf->dev, "Not able to get a minor"
1483			" (base %u, slice default): %d\n", USBTMC_MINOR_BASE,
1484			retcode);
1485		goto error_register;
1486	}
1487	dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor);
1488
1489	return 0;
1490
1491error_register:
1492	sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1493	sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
1494	usbtmc_free_int(data);
1495err_put:
1496	kref_put(&data->kref, usbtmc_delete);
1497	return retcode;
1498}
1499
1500static void usbtmc_disconnect(struct usb_interface *intf)
1501{
1502	struct usbtmc_device_data *data;
1503
1504	dev_dbg(&intf->dev, "usbtmc_disconnect called\n");
1505
1506	data = usb_get_intfdata(intf);
1507	usb_deregister_dev(intf, &usbtmc_class);
1508	sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1509	sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
1510	mutex_lock(&data->io_mutex);
1511	data->zombie = 1;
1512	wake_up_all(&data->waitq);
1513	mutex_unlock(&data->io_mutex);
1514	usbtmc_free_int(data);
1515	kref_put(&data->kref, usbtmc_delete);
1516}
1517
1518static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message)
1519{
1520	/* this driver does not have pending URBs */
1521	return 0;
1522}
1523
1524static int usbtmc_resume(struct usb_interface *intf)
1525{
1526	return 0;
1527}
1528
1529static struct usb_driver usbtmc_driver = {
1530	.name		= "usbtmc",
1531	.id_table	= usbtmc_devices,
1532	.probe		= usbtmc_probe,
1533	.disconnect	= usbtmc_disconnect,
1534	.suspend	= usbtmc_suspend,
1535	.resume		= usbtmc_resume,
1536};
1537
1538module_usb_driver(usbtmc_driver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1539
1540MODULE_LICENSE("GPL");