- 根目录:
- drivers
- usb
- class
- usbtmc.c
/**
* drivers/usb/class/usbtmc.c - USB Test & Measurement class driver
*
* Copyright (C) 2007 Stefan Kopp, Gechingen, Germany
* Copyright (C) 2008 Novell, Inc.
* Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* The GNU General Public License is available at
* http://www.gnu.org/copyleft/gpl.html.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/kref.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/usb.h>
#include <linux/usb/tmc.h>
#define USBTMC_MINOR_BASE 176
/*
* Size of driver internal IO buffer. Must be multiple of 4 and at least as
* large as wMaxPacketSize (which is usually 512 bytes).
*/
#define USBTMC_SIZE_IOBUFFER 2048
/* Default USB timeout (in milliseconds) */
#define USBTMC_TIMEOUT 5000
/*
* Maximum number of read cycles to empty bulk in endpoint during CLEAR and
* ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
* packet is never read.
*/
#define USBTMC_MAX_READS_TO_CLEAR_BULK_IN 100
static const struct usb_device_id usbtmc_devices[] = {
{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), },
{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), },
{ 0, } /* terminating entry */
};
MODULE_DEVICE_TABLE(usb, usbtmc_devices);
/*
* This structure is the capabilities for the device
* See section 4.2.1.8 of the USBTMC specification,
* and section 4.2.2 of the USBTMC usb488 subclass
* specification for details.
*/
struct usbtmc_dev_capabilities {
__u8 interface_capabilities;
__u8 device_capabilities;
__u8 usb488_interface_capabilities;
__u8 usb488_device_capabilities;
};
/* This structure holds private data for each USBTMC device. One copy is
* allocated for each USBTMC device in the driver's probe function.
*/
struct usbtmc_device_data {
const struct usb_device_id *id;
struct usb_device *usb_dev;
struct usb_interface *intf;
unsigned int bulk_in;
unsigned int bulk_out;
u8 bTag;
u8 bTag_last_write; /* needed for abort */
u8 bTag_last_read; /* needed for abort */
/* attributes from the USB TMC spec for this device */
u8 TermChar;
bool TermCharEnabled;
bool auto_abort;
bool zombie; /* fd of disconnected device */
struct usbtmc_dev_capabilities capabilities;
struct kref kref;
struct mutex io_mutex; /* only one i/o function running at a time */
};
#define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref)
/* Forward declarations */
static struct usb_driver usbtmc_driver;
static void usbtmc_delete(struct kref *kref)
{
struct usbtmc_device_data *data = to_usbtmc_data(kref);
usb_put_dev(data->usb_dev);
kfree(data);
}
static int usbtmc_open(struct inode *inode, struct file *filp)
{
struct usb_interface *intf;
struct usbtmc_device_data *data;
int retval = 0;
intf = usb_find_interface(&usbtmc_driver, iminor(inode));
if (!intf) {
printk(KERN_ERR KBUILD_MODNAME
": can not find device for minor %d", iminor(inode));
retval = -ENODEV;
goto exit;
}
data = usb_get_intfdata(intf);
kref_get(&data->kref);
/* Store pointer in file structure's private data field */
filp->private_data = data;
exit:
return retval;
}
static int usbtmc_release(struct inode *inode, struct file *file)
{
struct usbtmc_device_data *data = file->private_data;
kref_put(&data->kref, usbtmc_delete);
return 0;
}
static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data)
{
u8 *buffer;
struct device *dev;
int rv;
int n;
int actual;
struct usb_host_interface *current_setting;
int max_size;
dev = &data->intf->dev;
buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_INITIATE_ABORT_BULK_IN,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
data->bTag_last_read, data->bulk_in,
buffer, 2, USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
if (buffer[0] == USBTMC_STATUS_FAILED) {
rv = 0;
goto exit;
}
if (buffer[0] != USBTMC_STATUS_SUCCESS) {
dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n",
buffer[0]);
rv = -EPERM;
goto exit;
}
max_size = 0;
current_setting = data->intf->cur_altsetting;
for (n = 0; n < current_setting->desc.bNumEndpoints; n++)
if (current_setting->endpoint[n].desc.bEndpointAddress ==
data->bulk_in)
max_size = usb_endpoint_maxp(¤t_setting->endpoint[n].desc);
if (max_size == 0) {
dev_err(dev, "Couldn't get wMaxPacketSize\n");
rv = -EPERM;
goto exit;
}
dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size);
n = 0;
do {
dev_dbg(dev, "Reading from bulk in EP\n");
rv = usb_bulk_msg(data->usb_dev,
usb_rcvbulkpipe(data->usb_dev,
data->bulk_in),
buffer, USBTMC_SIZE_IOBUFFER,
&actual, USBTMC_TIMEOUT);
n++;
if (rv < 0) {
dev_err(dev, "usb_bulk_msg returned %d\n", rv);
goto exit;
}
} while ((actual == max_size) &&
(n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
if (actual == max_size) {
dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
rv = -EPERM;
goto exit;
}
n = 0;
usbtmc_abort_bulk_in_status:
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
0, data->bulk_in, buffer, 0x08,
USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
if (buffer[0] == USBTMC_STATUS_SUCCESS) {
rv = 0;
goto exit;
}
if (buffer[0] != USBTMC_STATUS_PENDING) {
dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
rv = -EPERM;
goto exit;
}
if (buffer[1] == 1)
do {
dev_dbg(dev, "Reading from bulk in EP\n");
rv = usb_bulk_msg(data->usb_dev,
usb_rcvbulkpipe(data->usb_dev,
data->bulk_in),
buffer, USBTMC_SIZE_IOBUFFER,
&actual, USBTMC_TIMEOUT);
n++;
if (rv < 0) {
dev_err(dev, "usb_bulk_msg returned %d\n", rv);
goto exit;
}
} while ((actual == max_size) &&
(n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
if (actual == max_size) {
dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
rv = -EPERM;
goto exit;
}
goto usbtmc_abort_bulk_in_status;
exit:
kfree(buffer);
return rv;
}
static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
{
struct device *dev;
u8 *buffer;
int rv;
int n;
dev = &data->intf->dev;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
data->bTag_last_write, data->bulk_out,
buffer, 2, USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]);
if (buffer[0] != USBTMC_STATUS_SUCCESS) {
dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n",
buffer[0]);
rv = -EPERM;
goto exit;
}
n = 0;
usbtmc_abort_bulk_out_check_status:
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
0, data->bulk_out, buffer, 0x08,
USBTMC_TIMEOUT);
n++;
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]);
if (buffer[0] == USBTMC_STATUS_SUCCESS)
goto usbtmc_abort_bulk_out_clear_halt;
if ((buffer[0] == USBTMC_STATUS_PENDING) &&
(n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN))
goto usbtmc_abort_bulk_out_check_status;
rv = -EPERM;
goto exit;
usbtmc_abort_bulk_out_clear_halt:
rv = usb_clear_halt(data->usb_dev,
usb_sndbulkpipe(data->usb_dev, data->bulk_out));
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
rv = 0;
exit:
kfree(buffer);
return rv;
}
static ssize_t usbtmc_read(struct file *filp, char __user *buf,
size_t count, loff_t *f_pos)
{
struct usbtmc_device_data *data;
struct device *dev;
u32 n_characters;
u8 *buffer;
int actual;
size_t done;
size_t remaining;
int retval;
size_t this_part;
/* Get pointer to private data structure */
data = filp->private_data;
dev = &data->intf->dev;
buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
mutex_lock(&data->io_mutex);
if (data->zombie) {
retval = -ENODEV;
goto exit;
}
remaining = count;
done = 0;
while (remaining > 0) {
if (remaining > USBTMC_SIZE_IOBUFFER - 12 - 3)
this_part = USBTMC_SIZE_IOBUFFER - 12 - 3;
else
this_part = remaining;
/* Setup IO buffer for DEV_DEP_MSG_IN message
* Refer to class specs for details
*/
buffer[0] = 2;
buffer[1] = data->bTag;
buffer[2] = ~(data->bTag);
buffer[3] = 0; /* Reserved */
buffer[4] = (this_part) & 255;
buffer[5] = ((this_part) >> 8) & 255;
buffer[6] = ((this_part) >> 16) & 255;
buffer[7] = ((this_part) >> 24) & 255;
buffer[8] = data->TermCharEnabled * 2;
/* Use term character? */
buffer[9] = data->TermChar;
buffer[10] = 0; /* Reserved */
buffer[11] = 0; /* Reserved */
/* Send bulk URB */
retval = usb_bulk_msg(data->usb_dev,
usb_sndbulkpipe(data->usb_dev,
data->bulk_out),
buffer, 12, &actual, USBTMC_TIMEOUT);
/* Store bTag (in case we need to abort) */
data->bTag_last_write = data->bTag;
/* Increment bTag -- and increment again if zero */
data->bTag++;
if (!data->bTag)
(data->bTag)++;
if (retval < 0) {
dev_err(dev, "usb_bulk_msg returned %d\n", retval);
if (data->auto_abort)
usbtmc_ioctl_abort_bulk_out(data);
goto exit;
}
/* Send bulk URB */
retval = usb_bulk_msg(data->usb_dev,
usb_rcvbulkpipe(data->usb_dev,
data->bulk_in),
buffer, USBTMC_SIZE_IOBUFFER, &actual,
USBTMC_TIMEOUT);
/* Store bTag (in case we need to abort) */
data->bTag_last_read = data->bTag;
if (retval < 0) {
dev_err(dev, "Unable to read data, error %d\n", retval);
if (data->auto_abort)
usbtmc_ioctl_abort_bulk_in(data);
goto exit;
}
/* How many characters did the instrument send? */
n_characters = buffer[4] +
(buffer[5] << 8) +
(buffer[6] << 16) +
(buffer[7] << 24);
/* Ensure the instrument doesn't lie about it */
if(n_characters > actual - 12) {
dev_err(dev, "Device lies about message size: %u > %d\n", n_characters, actual - 12);
n_characters = actual - 12;
}
/* Ensure the instrument doesn't send more back than requested */
if(n_characters > this_part) {
dev_err(dev, "Device returns more than requested: %zu > %zu\n", done + n_characters, done + this_part);
n_characters = this_part;
}
/* Bound amount of data received by amount of data requested */
if (n_characters > this_part)
n_characters = this_part;
/* Copy buffer to user space */
if (copy_to_user(buf + done, &buffer[12], n_characters)) {
/* There must have been an addressing problem */
retval = -EFAULT;
goto exit;
}
done += n_characters;
/* Terminate if end-of-message bit received from device */
if ((buffer[8] & 0x01) && (actual >= n_characters + 12))
remaining = 0;
else
remaining -= n_characters;
}
/* Update file position value */
*f_pos = *f_pos + done;
retval = done;
exit:
mutex_unlock(&data->io_mutex);
kfree(buffer);
return retval;
}
static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
size_t count, loff_t *f_pos)
{
struct usbtmc_device_data *data;
u8 *buffer;
int retval;
int actual;
unsigned long int n_bytes;
int remaining;
int done;
int this_part;
data = filp->private_data;
buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
mutex_lock(&data->io_mutex);
if (data->zombie) {
retval = -ENODEV;
goto exit;
}
remaining = count;
done = 0;
while (remaining > 0) {
if (remaining > USBTMC_SIZE_IOBUFFER - 12) {
this_part = USBTMC_SIZE_IOBUFFER - 12;
buffer[8] = 0;
} else {
this_part = remaining;
buffer[8] = 1;
}
/* Setup IO buffer for DEV_DEP_MSG_OUT message */
buffer[0] = 1;
buffer[1] = data->bTag;
buffer[2] = ~(data->bTag);
buffer[3] = 0; /* Reserved */
buffer[4] = this_part & 255;
buffer[5] = (this_part >> 8) & 255;
buffer[6] = (this_part >> 16) & 255;
buffer[7] = (this_part >> 24) & 255;
/* buffer[8] is set above... */
buffer[9] = 0; /* Reserved */
buffer[10] = 0; /* Reserved */
buffer[11] = 0; /* Reserved */
if (copy_from_user(&buffer[12], buf + done, this_part)) {
retval = -EFAULT;
goto exit;
}
n_bytes = roundup(12 + this_part, 4);
memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part));
do {
retval = usb_bulk_msg(data->usb_dev,
usb_sndbulkpipe(data->usb_dev,
data->bulk_out),
buffer, n_bytes,
&actual, USBTMC_TIMEOUT);
if (retval != 0)
break;
n_bytes -= actual;
} while (n_bytes);
data->bTag_last_write = data->bTag;
data->bTag++;
if (!data->bTag)
data->bTag++;
if (retval < 0) {
dev_err(&data->intf->dev,
"Unable to send data, error %d\n", retval);
if (data->auto_abort)
usbtmc_ioctl_abort_bulk_out(data);
goto exit;
}
remaining -= this_part;
done += this_part;
}
retval = count;
exit:
mutex_unlock(&data->io_mutex);
kfree(buffer);
return retval;
}
static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
{
struct usb_host_interface *current_setting;
struct usb_endpoint_descriptor *desc;
struct device *dev;
u8 *buffer;
int rv;
int n;
int actual;
int max_size;
dev = &data->intf->dev;
dev_dbg(dev, "Sending INITIATE_CLEAR request\n");
buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_INITIATE_CLEAR,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
0, 0, buffer, 1, USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
if (buffer[0] != USBTMC_STATUS_SUCCESS) {
dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
rv = -EPERM;
goto exit;
}
max_size = 0;
current_setting = data->intf->cur_altsetting;
for (n = 0; n < current_setting->desc.bNumEndpoints; n++) {
desc = ¤t_setting->endpoint[n].desc;
if (desc->bEndpointAddress == data->bulk_in)
max_size = usb_endpoint_maxp(desc);
}
if (max_size == 0) {
dev_err(dev, "Couldn't get wMaxPacketSize\n");
rv = -EPERM;
goto exit;
}
dev_dbg(dev, "wMaxPacketSize is %d\n", max_size);
n = 0;
usbtmc_clear_check_status:
dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n");
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_CHECK_CLEAR_STATUS,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
0, 0, buffer, 2, USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
if (buffer[0] == USBTMC_STATUS_SUCCESS)
goto usbtmc_clear_bulk_out_halt;
if (buffer[0] != USBTMC_STATUS_PENDING) {
dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
rv = -EPERM;
goto exit;
}
if (buffer[1] == 1)
do {
dev_dbg(dev, "Reading from bulk in EP\n");
rv = usb_bulk_msg(data->usb_dev,
usb_rcvbulkpipe(data->usb_dev,
data->bulk_in),
buffer, USBTMC_SIZE_IOBUFFER,
&actual, USBTMC_TIMEOUT);
n++;
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n",
rv);
goto exit;
}
} while ((actual == max_size) &&
(n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
if (actual == max_size) {
dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
rv = -EPERM;
goto exit;
}
goto usbtmc_clear_check_status;
usbtmc_clear_bulk_out_halt:
rv = usb_clear_halt(data->usb_dev,
usb_sndbulkpipe(data->usb_dev, data->bulk_out));
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
rv = 0;
exit:
kfree(buffer);
return rv;
}
static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
{
int rv;
rv = usb_clear_halt(data->usb_dev,
usb_sndbulkpipe(data->usb_dev, data->bulk_out));
if (rv < 0) {
dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
rv);
return rv;
}
return 0;
}
static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
{
int rv;
rv = usb_clear_halt(data->usb_dev,
usb_rcvbulkpipe(data->usb_dev, data->bulk_in));
if (rv < 0) {
dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
rv);
return rv;
}
return 0;
}
static int get_capabilities(struct usbtmc_device_data *data)
{
struct device *dev = &data->usb_dev->dev;
char *buffer;
int rv = 0;
buffer = kmalloc(0x18, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_GET_CAPABILITIES,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
0, 0, buffer, 0x18, USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto err_out;
}
dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
if (buffer[0] != USBTMC_STATUS_SUCCESS) {
dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
rv = -EPERM;
goto err_out;
}
dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
data->capabilities.interface_capabilities = buffer[4];
data->capabilities.device_capabilities = buffer[5];
data->capabilities.usb488_interface_capabilities = buffer[14];
data->capabilities.usb488_device_capabilities = buffer[15];
rv = 0;
err_out:
kfree(buffer);
return rv;
}
#define capability_attribute(name) \
static ssize_t show_##name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
struct usbtmc_device_data *data = usb_get_intfdata(intf); \
\
return sprintf(buf, "%d\n", data->capabilities.name); \
} \
static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
capability_attribute(interface_capabilities);
capability_attribute(device_capabilities);
capability_attribute(usb488_interface_capabilities);
capability_attribute(usb488_device_capabilities);
static struct attribute *capability_attrs[] = {
&dev_attr_interface_capabilities.attr,
&dev_attr_device_capabilities.attr,
&dev_attr_usb488_interface_capabilities.attr,
&dev_attr_usb488_device_capabilities.attr,
NULL,
};
static struct attribute_group capability_attr_grp = {
.attrs = capability_attrs,
};
static ssize_t show_TermChar(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usbtmc_device_data *data = usb_get_intfdata(intf);
return sprintf(buf, "%c\n", data->TermChar);
}
static ssize_t store_TermChar(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usbtmc_device_data *data = usb_get_intfdata(intf);
if (count < 1)
return -EINVAL;
data->TermChar = buf[0];
return count;
}
static DEVICE_ATTR(TermChar, S_IRUGO, show_TermChar, store_TermChar);
#define data_attribute(name) \
static ssize_t show_##name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
struct usbtmc_device_data *data = usb_get_intfdata(intf); \
\
return sprintf(buf, "%d\n", data->name); \
} \
static ssize_t store_##name(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
struct usbtmc_device_data *data = usb_get_intfdata(intf); \
ssize_t result; \
unsigned val; \
\
result = sscanf(buf, "%u\n", &val); \
if (result != 1) \
result = -EINVAL; \
data->name = val; \
if (result < 0) \
return result; \
else \
return count; \
} \
static DEVICE_ATTR(name, S_IRUGO, show_##name, store_##name)
data_attribute(TermCharEnabled);
data_attribute(auto_abort);
static struct attribute *data_attrs[] = {
&dev_attr_TermChar.attr,
&dev_attr_TermCharEnabled.attr,
&dev_attr_auto_abort.attr,
NULL,
};
static struct attribute_group data_attr_grp = {
.attrs = data_attrs,
};
static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data)
{
struct device *dev;
u8 *buffer;
int rv;
dev = &data->intf->dev;
buffer = kmalloc(2, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
rv = usb_control_msg(data->usb_dev,
usb_rcvctrlpipe(data->usb_dev, 0),
USBTMC_REQUEST_INDICATOR_PULSE,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
0, 0, buffer, 0x01, USBTMC_TIMEOUT);
if (rv < 0) {
dev_err(dev, "usb_control_msg returned %d\n", rv);
goto exit;
}
dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
if (buffer[0] != USBTMC_STATUS_SUCCESS) {
dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
rv = -EPERM;
goto exit;
}
rv = 0;
exit:
kfree(buffer);
return rv;
}
static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct usbtmc_device_data *data;
int retval = -EBADRQC;
data = file->private_data;
mutex_lock(&data->io_mutex);
if (data->zombie) {
retval = -ENODEV;
goto skip_io_on_zombie;
}
switch (cmd) {
case USBTMC_IOCTL_CLEAR_OUT_HALT:
retval = usbtmc_ioctl_clear_out_halt(data);
break;
case USBTMC_IOCTL_CLEAR_IN_HALT:
retval = usbtmc_ioctl_clear_in_halt(data);
break;
case USBTMC_IOCTL_INDICATOR_PULSE:
retval = usbtmc_ioctl_indicator_pulse(data);
break;
case USBTMC_IOCTL_CLEAR:
retval = usbtmc_ioctl_clear(data);
break;
case USBTMC_IOCTL_ABORT_BULK_OUT:
retval = usbtmc_ioctl_abort_bulk_out(data);
break;
case USBTMC_IOCTL_ABORT_BULK_IN:
retval = usbtmc_ioctl_abort_bulk_in(data);
break;
}
skip_io_on_zombie:
mutex_unlock(&data->io_mutex);
return retval;
}
static const struct file_operations fops = {
.owner = THIS_MODULE,
.read = usbtmc_read,
.write = usbtmc_write,
.open = usbtmc_open,
.release = usbtmc_release,
.unlocked_ioctl = usbtmc_ioctl,
.llseek = default_llseek,
};
static struct usb_class_driver usbtmc_class = {
.name = "usbtmc%d",
.fops = &fops,
.minor_base = USBTMC_MINOR_BASE,
};
static int usbtmc_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usbtmc_device_data *data;
struct usb_host_interface *iface_desc;
struct usb_endpoint_descriptor *endpoint;
int n;
int retcode;
dev_dbg(&intf->dev, "%s called\n", __func__);
data = kmalloc(sizeof(struct usbtmc_device_data), GFP_KERNEL);
if (!data) {
dev_err(&intf->dev, "Unable to allocate kernel memory\n");
return -ENOMEM;
}
data->intf = intf;
data->id = id;
data->usb_dev = usb_get_dev(interface_to_usbdev(intf));
usb_set_intfdata(intf, data);
kref_init(&data->kref);
mutex_init(&data->io_mutex);
data->zombie = 0;
/* Initialize USBTMC bTag and other fields */
data->bTag = 1;
data->TermCharEnabled = 0;
data->TermChar = '\n';
/* USBTMC devices have only one setting, so use that */
iface_desc = data->intf->cur_altsetting;
/* Find bulk in endpoint */
for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
endpoint = &iface_desc->endpoint[n].desc;
if (usb_endpoint_is_bulk_in(endpoint)) {
data->bulk_in = endpoint->bEndpointAddress;
dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n",
data->bulk_in);
break;
}
}
/* Find bulk out endpoint */
for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
endpoint = &iface_desc->endpoint[n].desc;
if (usb_endpoint_is_bulk_out(endpoint)) {
data->bulk_out = endpoint->bEndpointAddress;
dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n",
data->bulk_out);
break;
}
}
retcode = get_capabilities(data);
if (retcode)
dev_err(&intf->dev, "can't read capabilities\n");
else
retcode = sysfs_create_group(&intf->dev.kobj,
&capability_attr_grp);
retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp);
retcode = usb_register_dev(intf, &usbtmc_class);
if (retcode) {
dev_err(&intf->dev, "Not able to get a minor"
" (base %u, slice default): %d\n", USBTMC_MINOR_BASE,
retcode);
goto error_register;
}
dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor);
return 0;
error_register:
sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
kref_put(&data->kref, usbtmc_delete);
return retcode;
}
static void usbtmc_disconnect(struct usb_interface *intf)
{
struct usbtmc_device_data *data;
dev_dbg(&intf->dev, "usbtmc_disconnect called\n");
data = usb_get_intfdata(intf);
usb_deregister_dev(intf, &usbtmc_class);
sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
mutex_lock(&data->io_mutex);
data->zombie = 1;
mutex_unlock(&data->io_mutex);
kref_put(&data->kref, usbtmc_delete);
}
static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message)
{
/* this driver does not have pending URBs */
return 0;
}
static int usbtmc_resume(struct usb_interface *intf)
{
return 0;
}
static struct usb_driver usbtmc_driver = {
.name = "usbtmc",
.id_table = usbtmc_devices,
.probe = usbtmc_probe,
.disconnect = usbtmc_disconnect,
.suspend = usbtmc_suspend,
.resume = usbtmc_resume,
};
module_usb_driver(usbtmc_driver);
MODULE_LICENSE("GPL");