683 lines
18 KiB
C
683 lines
18 KiB
C
/*
|
|
* devices.c
|
|
* (C) Copyright 1999 Randy Dunlap.
|
|
* (C) Copyright 1999,2000 Thomas Sailer <sailer@ife.ee.ethz.ch>. (proc file per device)
|
|
* (C) Copyright 1999 Deti Fliegl (new USB architecture)
|
|
*
|
|
* 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.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*
|
|
*************************************************************
|
|
*
|
|
* <mountpoint>/devices contains USB topology, device, config, class,
|
|
* interface, & endpoint data.
|
|
*
|
|
* I considered using /proc/bus/usb/devices/device# for each device
|
|
* as it is attached or detached, but I didn't like this for some
|
|
* reason -- maybe it's just too deep of a directory structure.
|
|
* I also don't like looking in multiple places to gather and view
|
|
* the data. Having only one file for ./devices also prevents race
|
|
* conditions that could arise if a program was reading device info
|
|
* for devices that are being removed (unplugged). (That is, the
|
|
* program may find a directory for devnum_12 then try to open it,
|
|
* but it was just unplugged, so the directory is now deleted.
|
|
* But programs would just have to be prepared for situations like
|
|
* this in any plug-and-play environment.)
|
|
*
|
|
* 1999-12-16: Thomas Sailer <sailer@ife.ee.ethz.ch>
|
|
* Converted the whole proc stuff to real
|
|
* read methods. Now not the whole device list needs to fit
|
|
* into one page, only the device list for one bus.
|
|
* Added a poll method to /proc/bus/usb/devices, to wake
|
|
* up an eventual usbd
|
|
* 2000-01-04: Thomas Sailer <sailer@ife.ee.ethz.ch>
|
|
* Turned into its own filesystem
|
|
* 2000-07-05: Ashley Montanaro <ashley@compsoc.man.ac.uk>
|
|
* Converted file reading routine to dump to buffer once
|
|
* per device, not per bus
|
|
*
|
|
* $Id: devices.c,v 1.5 2000/01/11 13:58:21 tom Exp $
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/usb.h>
|
|
#include <linux/smp_lock.h>
|
|
#include <linux/usbdevice_fs.h>
|
|
#include <linux/mutex.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#include "usb.h"
|
|
#include "hcd.h"
|
|
|
|
#define MAX_TOPO_LEVEL 6
|
|
|
|
/* Define ALLOW_SERIAL_NUMBER if you want to see the serial number of devices */
|
|
#define ALLOW_SERIAL_NUMBER
|
|
|
|
static const char *format_topo =
|
|
/* T: Bus=dd Lev=dd Prnt=dd Port=dd Cnt=dd Dev#=ddd Spd=ddd MxCh=dd */
|
|
"\nT: Bus=%2.2d Lev=%2.2d Prnt=%2.2d Port=%2.2d Cnt=%2.2d Dev#=%3d Spd=%3s MxCh=%2d\n";
|
|
|
|
static const char *format_string_manufacturer =
|
|
/* S: Manufacturer=xxxx */
|
|
"S: Manufacturer=%.100s\n";
|
|
|
|
static const char *format_string_product =
|
|
/* S: Product=xxxx */
|
|
"S: Product=%.100s\n";
|
|
|
|
#ifdef ALLOW_SERIAL_NUMBER
|
|
static const char *format_string_serialnumber =
|
|
/* S: SerialNumber=xxxx */
|
|
"S: SerialNumber=%.100s\n";
|
|
#endif
|
|
|
|
static const char *format_bandwidth =
|
|
/* B: Alloc=ddd/ddd us (xx%), #Int=ddd, #Iso=ddd */
|
|
"B: Alloc=%3d/%3d us (%2d%%), #Int=%3d, #Iso=%3d\n";
|
|
|
|
static const char *format_device1 =
|
|
/* D: Ver=xx.xx Cls=xx(sssss) Sub=xx Prot=xx MxPS=dd #Cfgs=dd */
|
|
"D: Ver=%2x.%02x Cls=%02x(%-5s) Sub=%02x Prot=%02x MxPS=%2d #Cfgs=%3d\n";
|
|
|
|
static const char *format_device2 =
|
|
/* P: Vendor=xxxx ProdID=xxxx Rev=xx.xx */
|
|
"P: Vendor=%04x ProdID=%04x Rev=%2x.%02x\n";
|
|
|
|
static const char *format_config =
|
|
/* C: #Ifs=dd Cfg#=dd Atr=xx MPwr=dddmA */
|
|
"C:%c #Ifs=%2d Cfg#=%2d Atr=%02x MxPwr=%3dmA\n";
|
|
|
|
static const char *format_iface =
|
|
/* I: If#=dd Alt=dd #EPs=dd Cls=xx(sssss) Sub=xx Prot=xx Driver=xxxx*/
|
|
"I:%c If#=%2d Alt=%2d #EPs=%2d Cls=%02x(%-5s) Sub=%02x Prot=%02x Driver=%s\n";
|
|
|
|
static const char *format_endpt =
|
|
/* E: Ad=xx(s) Atr=xx(ssss) MxPS=dddd Ivl=D?s */
|
|
"E: Ad=%02x(%c) Atr=%02x(%-4s) MxPS=%4d Ivl=%d%cs\n";
|
|
|
|
|
|
/*
|
|
* Need access to the driver and USB bus lists.
|
|
* extern struct list_head usb_bus_list;
|
|
* However, these will come from functions that return ptrs to each of them.
|
|
*/
|
|
|
|
static DECLARE_WAIT_QUEUE_HEAD(deviceconndiscwq);
|
|
static unsigned int conndiscevcnt = 0;
|
|
|
|
/* this struct stores the poll state for <mountpoint>/devices pollers */
|
|
struct usb_device_status {
|
|
unsigned int lastev;
|
|
};
|
|
|
|
struct class_info {
|
|
int class;
|
|
char *class_name;
|
|
};
|
|
|
|
static const struct class_info clas_info[] =
|
|
{ /* max. 5 chars. per name string */
|
|
{USB_CLASS_PER_INTERFACE, ">ifc"},
|
|
{USB_CLASS_AUDIO, "audio"},
|
|
{USB_CLASS_COMM, "comm."},
|
|
{USB_CLASS_HID, "HID"},
|
|
{USB_CLASS_HUB, "hub"},
|
|
{USB_CLASS_PHYSICAL, "PID"},
|
|
{USB_CLASS_PRINTER, "print"},
|
|
{USB_CLASS_MASS_STORAGE, "stor."},
|
|
{USB_CLASS_CDC_DATA, "data"},
|
|
{USB_CLASS_APP_SPEC, "app."},
|
|
{USB_CLASS_VENDOR_SPEC, "vend."},
|
|
{USB_CLASS_STILL_IMAGE, "still"},
|
|
{USB_CLASS_CSCID, "scard"},
|
|
{USB_CLASS_CONTENT_SEC, "c-sec"},
|
|
{-1, "unk."} /* leave as last */
|
|
};
|
|
|
|
/*****************************************************************/
|
|
|
|
void usbfs_conn_disc_event(void)
|
|
{
|
|
conndiscevcnt++;
|
|
wake_up(&deviceconndiscwq);
|
|
}
|
|
|
|
static const char *class_decode(const int class)
|
|
{
|
|
int ix;
|
|
|
|
for (ix = 0; clas_info[ix].class != -1; ix++)
|
|
if (clas_info[ix].class == class)
|
|
break;
|
|
return clas_info[ix].class_name;
|
|
}
|
|
|
|
static char *usb_dump_endpoint_descriptor(
|
|
int speed,
|
|
char *start,
|
|
char *end,
|
|
const struct usb_endpoint_descriptor *desc
|
|
)
|
|
{
|
|
char dir, unit, *type;
|
|
unsigned interval, bandwidth = 1;
|
|
|
|
if (start > end)
|
|
return start;
|
|
|
|
dir = usb_endpoint_dir_in(desc) ? 'I' : 'O';
|
|
|
|
if (speed == USB_SPEED_HIGH) {
|
|
switch (le16_to_cpu(desc->wMaxPacketSize) & (0x03 << 11)) {
|
|
case 1 << 11: bandwidth = 2; break;
|
|
case 2 << 11: bandwidth = 3; break;
|
|
}
|
|
}
|
|
|
|
/* this isn't checking for illegal values */
|
|
switch (desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
|
|
case USB_ENDPOINT_XFER_CONTROL:
|
|
type = "Ctrl";
|
|
if (speed == USB_SPEED_HIGH) /* uframes per NAK */
|
|
interval = desc->bInterval;
|
|
else
|
|
interval = 0;
|
|
dir = 'B'; /* ctrl is bidirectional */
|
|
break;
|
|
case USB_ENDPOINT_XFER_ISOC:
|
|
type = "Isoc";
|
|
interval = 1 << (desc->bInterval - 1);
|
|
break;
|
|
case USB_ENDPOINT_XFER_BULK:
|
|
type = "Bulk";
|
|
if (speed == USB_SPEED_HIGH && dir == 'O') /* uframes per NAK */
|
|
interval = desc->bInterval;
|
|
else
|
|
interval = 0;
|
|
break;
|
|
case USB_ENDPOINT_XFER_INT:
|
|
type = "Int.";
|
|
if (speed == USB_SPEED_HIGH)
|
|
interval = 1 << (desc->bInterval - 1);
|
|
else
|
|
interval = desc->bInterval;
|
|
break;
|
|
default: /* "can't happen" */
|
|
return start;
|
|
}
|
|
interval *= (speed == USB_SPEED_HIGH) ? 125 : 1000;
|
|
if (interval % 1000)
|
|
unit = 'u';
|
|
else {
|
|
unit = 'm';
|
|
interval /= 1000;
|
|
}
|
|
|
|
start += sprintf(start, format_endpt, desc->bEndpointAddress, dir,
|
|
desc->bmAttributes, type,
|
|
(le16_to_cpu(desc->wMaxPacketSize) & 0x07ff) * bandwidth,
|
|
interval, unit);
|
|
return start;
|
|
}
|
|
|
|
static char *usb_dump_interface_descriptor(char *start, char *end,
|
|
const struct usb_interface_cache *intfc,
|
|
const struct usb_interface *iface,
|
|
int setno)
|
|
{
|
|
const struct usb_interface_descriptor *desc = &intfc->altsetting[setno].desc;
|
|
const char *driver_name = "";
|
|
int active = 0;
|
|
|
|
if (start > end)
|
|
return start;
|
|
down_read(&usb_bus_type.subsys.rwsem);
|
|
if (iface) {
|
|
driver_name = (iface->dev.driver
|
|
? iface->dev.driver->name
|
|
: "(none)");
|
|
active = (desc == &iface->cur_altsetting->desc);
|
|
}
|
|
start += sprintf(start, format_iface,
|
|
active ? '*' : ' ', /* mark active altsetting */
|
|
desc->bInterfaceNumber,
|
|
desc->bAlternateSetting,
|
|
desc->bNumEndpoints,
|
|
desc->bInterfaceClass,
|
|
class_decode(desc->bInterfaceClass),
|
|
desc->bInterfaceSubClass,
|
|
desc->bInterfaceProtocol,
|
|
driver_name);
|
|
up_read(&usb_bus_type.subsys.rwsem);
|
|
return start;
|
|
}
|
|
|
|
static char *usb_dump_interface(
|
|
int speed,
|
|
char *start,
|
|
char *end,
|
|
const struct usb_interface_cache *intfc,
|
|
const struct usb_interface *iface,
|
|
int setno
|
|
) {
|
|
const struct usb_host_interface *desc = &intfc->altsetting[setno];
|
|
int i;
|
|
|
|
start = usb_dump_interface_descriptor(start, end, intfc, iface, setno);
|
|
for (i = 0; i < desc->desc.bNumEndpoints; i++) {
|
|
if (start > end)
|
|
return start;
|
|
start = usb_dump_endpoint_descriptor(speed,
|
|
start, end, &desc->endpoint[i].desc);
|
|
}
|
|
return start;
|
|
}
|
|
|
|
/* TBD:
|
|
* 0. TBDs
|
|
* 1. marking active interface altsettings (code lists all, but should mark
|
|
* which ones are active, if any)
|
|
*/
|
|
|
|
static char *usb_dump_config_descriptor(char *start, char *end, const struct usb_config_descriptor *desc, int active)
|
|
{
|
|
if (start > end)
|
|
return start;
|
|
start += sprintf(start, format_config,
|
|
active ? '*' : ' ', /* mark active/actual/current cfg. */
|
|
desc->bNumInterfaces,
|
|
desc->bConfigurationValue,
|
|
desc->bmAttributes,
|
|
desc->bMaxPower * 2);
|
|
return start;
|
|
}
|
|
|
|
static char *usb_dump_config (
|
|
int speed,
|
|
char *start,
|
|
char *end,
|
|
const struct usb_host_config *config,
|
|
int active
|
|
)
|
|
{
|
|
int i, j;
|
|
struct usb_interface_cache *intfc;
|
|
struct usb_interface *interface;
|
|
|
|
if (start > end)
|
|
return start;
|
|
if (!config) /* getting these some in 2.3.7; none in 2.3.6 */
|
|
return start + sprintf(start, "(null Cfg. desc.)\n");
|
|
start = usb_dump_config_descriptor(start, end, &config->desc, active);
|
|
for (i = 0; i < config->desc.bNumInterfaces; i++) {
|
|
intfc = config->intf_cache[i];
|
|
interface = config->interface[i];
|
|
for (j = 0; j < intfc->num_altsetting; j++) {
|
|
if (start > end)
|
|
return start;
|
|
start = usb_dump_interface(speed,
|
|
start, end, intfc, interface, j);
|
|
}
|
|
}
|
|
return start;
|
|
}
|
|
|
|
/*
|
|
* Dump the different USB descriptors.
|
|
*/
|
|
static char *usb_dump_device_descriptor(char *start, char *end, const struct usb_device_descriptor *desc)
|
|
{
|
|
u16 bcdUSB = le16_to_cpu(desc->bcdUSB);
|
|
u16 bcdDevice = le16_to_cpu(desc->bcdDevice);
|
|
|
|
if (start > end)
|
|
return start;
|
|
start += sprintf(start, format_device1,
|
|
bcdUSB >> 8, bcdUSB & 0xff,
|
|
desc->bDeviceClass,
|
|
class_decode (desc->bDeviceClass),
|
|
desc->bDeviceSubClass,
|
|
desc->bDeviceProtocol,
|
|
desc->bMaxPacketSize0,
|
|
desc->bNumConfigurations);
|
|
if (start > end)
|
|
return start;
|
|
start += sprintf(start, format_device2,
|
|
le16_to_cpu(desc->idVendor),
|
|
le16_to_cpu(desc->idProduct),
|
|
bcdDevice >> 8, bcdDevice & 0xff);
|
|
return start;
|
|
}
|
|
|
|
/*
|
|
* Dump the different strings that this device holds.
|
|
*/
|
|
static char *usb_dump_device_strings(char *start, char *end, struct usb_device *dev)
|
|
{
|
|
if (start > end)
|
|
return start;
|
|
if (dev->manufacturer)
|
|
start += sprintf(start, format_string_manufacturer, dev->manufacturer);
|
|
if (start > end)
|
|
goto out;
|
|
if (dev->product)
|
|
start += sprintf(start, format_string_product, dev->product);
|
|
if (start > end)
|
|
goto out;
|
|
#ifdef ALLOW_SERIAL_NUMBER
|
|
if (dev->serial)
|
|
start += sprintf(start, format_string_serialnumber, dev->serial);
|
|
#endif
|
|
out:
|
|
return start;
|
|
}
|
|
|
|
static char *usb_dump_desc(char *start, char *end, struct usb_device *dev)
|
|
{
|
|
int i;
|
|
|
|
if (start > end)
|
|
return start;
|
|
|
|
start = usb_dump_device_descriptor(start, end, &dev->descriptor);
|
|
|
|
if (start > end)
|
|
return start;
|
|
|
|
start = usb_dump_device_strings(start, end, dev);
|
|
|
|
for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
|
|
if (start > end)
|
|
return start;
|
|
start = usb_dump_config(dev->speed,
|
|
start, end, dev->config + i,
|
|
/* active ? */
|
|
(dev->config + i) == dev->actconfig);
|
|
}
|
|
return start;
|
|
}
|
|
|
|
|
|
#ifdef PROC_EXTRA /* TBD: may want to add this code later */
|
|
|
|
static char *usb_dump_hub_descriptor(char *start, char *end, const struct usb_hub_descriptor * desc)
|
|
{
|
|
int leng = USB_DT_HUB_NONVAR_SIZE;
|
|
unsigned char *ptr = (unsigned char *)desc;
|
|
|
|
if (start > end)
|
|
return start;
|
|
start += sprintf(start, "Interface:");
|
|
while (leng && start <= end) {
|
|
start += sprintf(start, " %02x", *ptr);
|
|
ptr++; leng--;
|
|
}
|
|
*start++ = '\n';
|
|
return start;
|
|
}
|
|
|
|
static char *usb_dump_string(char *start, char *end, const struct usb_device *dev, char *id, int index)
|
|
{
|
|
if (start > end)
|
|
return start;
|
|
start += sprintf(start, "Interface:");
|
|
if (index <= dev->maxstring && dev->stringindex && dev->stringindex[index])
|
|
start += sprintf(start, "%s: %.100s ", id, dev->stringindex[index]);
|
|
return start;
|
|
}
|
|
|
|
#endif /* PROC_EXTRA */
|
|
|
|
/*****************************************************************/
|
|
|
|
/* This is a recursive function. Parameters:
|
|
* buffer - the user-space buffer to write data into
|
|
* nbytes - the maximum number of bytes to write
|
|
* skip_bytes - the number of bytes to skip before writing anything
|
|
* file_offset - the offset into the devices file on completion
|
|
* The caller must own the device lock.
|
|
*/
|
|
static ssize_t usb_device_dump(char __user **buffer, size_t *nbytes, loff_t *skip_bytes, loff_t *file_offset,
|
|
struct usb_device *usbdev, struct usb_bus *bus, int level, int index, int count)
|
|
{
|
|
int chix;
|
|
int ret, cnt = 0;
|
|
int parent_devnum = 0;
|
|
char *pages_start, *data_end, *speed;
|
|
unsigned int length;
|
|
ssize_t total_written = 0;
|
|
|
|
/* don't bother with anything else if we're not writing any data */
|
|
if (*nbytes <= 0)
|
|
return 0;
|
|
|
|
if (level > MAX_TOPO_LEVEL)
|
|
return 0;
|
|
/* allocate 2^1 pages = 8K (on i386); should be more than enough for one device */
|
|
if (!(pages_start = (char*) __get_free_pages(GFP_KERNEL,1)))
|
|
return -ENOMEM;
|
|
|
|
if (usbdev->parent && usbdev->parent->devnum != -1)
|
|
parent_devnum = usbdev->parent->devnum;
|
|
/*
|
|
* So the root hub's parent is 0 and any device that is
|
|
* plugged into the root hub has a parent of 0.
|
|
*/
|
|
switch (usbdev->speed) {
|
|
case USB_SPEED_LOW:
|
|
speed = "1.5"; break;
|
|
case USB_SPEED_UNKNOWN: /* usb 1.1 root hub code */
|
|
case USB_SPEED_FULL:
|
|
speed = "12 "; break;
|
|
case USB_SPEED_HIGH:
|
|
speed = "480"; break;
|
|
default:
|
|
speed = "?? ";
|
|
}
|
|
data_end = pages_start + sprintf(pages_start, format_topo,
|
|
bus->busnum, level, parent_devnum,
|
|
index, count, usbdev->devnum,
|
|
speed, usbdev->maxchild);
|
|
/*
|
|
* level = topology-tier level;
|
|
* parent_devnum = parent device number;
|
|
* index = parent's connector number;
|
|
* count = device count at this level
|
|
*/
|
|
/* If this is the root hub, display the bandwidth information */
|
|
if (level == 0) {
|
|
int max;
|
|
|
|
/* high speed reserves 80%, full/low reserves 90% */
|
|
if (usbdev->speed == USB_SPEED_HIGH)
|
|
max = 800;
|
|
else
|
|
max = FRAME_TIME_MAX_USECS_ALLOC;
|
|
|
|
/* report "average" periodic allocation over a microsecond.
|
|
* the schedules are actually bursty, HCDs need to deal with
|
|
* that and just compute/report this average.
|
|
*/
|
|
data_end += sprintf(data_end, format_bandwidth,
|
|
bus->bandwidth_allocated, max,
|
|
(100 * bus->bandwidth_allocated + max / 2)
|
|
/ max,
|
|
bus->bandwidth_int_reqs,
|
|
bus->bandwidth_isoc_reqs);
|
|
|
|
}
|
|
data_end = usb_dump_desc(data_end, pages_start + (2 * PAGE_SIZE) - 256, usbdev);
|
|
|
|
if (data_end > (pages_start + (2 * PAGE_SIZE) - 256))
|
|
data_end += sprintf(data_end, "(truncated)\n");
|
|
|
|
length = data_end - pages_start;
|
|
/* if we can start copying some data to the user */
|
|
if (length > *skip_bytes) {
|
|
length -= *skip_bytes;
|
|
if (length > *nbytes)
|
|
length = *nbytes;
|
|
if (copy_to_user(*buffer, pages_start + *skip_bytes, length)) {
|
|
free_pages((unsigned long)pages_start, 1);
|
|
return -EFAULT;
|
|
}
|
|
*nbytes -= length;
|
|
*file_offset += length;
|
|
total_written += length;
|
|
*buffer += length;
|
|
*skip_bytes = 0;
|
|
} else
|
|
*skip_bytes -= length;
|
|
|
|
free_pages((unsigned long)pages_start, 1);
|
|
|
|
/* Now look at all of this device's children. */
|
|
for (chix = 0; chix < usbdev->maxchild; chix++) {
|
|
struct usb_device *childdev = usbdev->children[chix];
|
|
|
|
if (childdev) {
|
|
usb_lock_device(childdev);
|
|
ret = usb_device_dump(buffer, nbytes, skip_bytes, file_offset, childdev,
|
|
bus, level + 1, chix, ++cnt);
|
|
usb_unlock_device(childdev);
|
|
if (ret == -EFAULT)
|
|
return total_written;
|
|
total_written += ret;
|
|
}
|
|
}
|
|
return total_written;
|
|
}
|
|
|
|
static ssize_t usb_device_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
|
|
{
|
|
struct usb_bus *bus;
|
|
ssize_t ret, total_written = 0;
|
|
loff_t skip_bytes = *ppos;
|
|
|
|
if (*ppos < 0)
|
|
return -EINVAL;
|
|
if (nbytes <= 0)
|
|
return 0;
|
|
if (!access_ok(VERIFY_WRITE, buf, nbytes))
|
|
return -EFAULT;
|
|
|
|
mutex_lock(&usb_bus_list_lock);
|
|
/* print devices for all busses */
|
|
list_for_each_entry(bus, &usb_bus_list, bus_list) {
|
|
/* recurse through all children of the root hub */
|
|
if (!bus->root_hub)
|
|
continue;
|
|
usb_lock_device(bus->root_hub);
|
|
ret = usb_device_dump(&buf, &nbytes, &skip_bytes, ppos, bus->root_hub, bus, 0, 0, 0);
|
|
usb_unlock_device(bus->root_hub);
|
|
if (ret < 0) {
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
return ret;
|
|
}
|
|
total_written += ret;
|
|
}
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
return total_written;
|
|
}
|
|
|
|
/* Kernel lock for "lastev" protection */
|
|
static unsigned int usb_device_poll(struct file *file, struct poll_table_struct *wait)
|
|
{
|
|
struct usb_device_status *st = file->private_data;
|
|
unsigned int mask = 0;
|
|
|
|
lock_kernel();
|
|
if (!st) {
|
|
st = kmalloc(sizeof(struct usb_device_status), GFP_KERNEL);
|
|
|
|
/* we may have dropped BKL - need to check for having lost the race */
|
|
if (file->private_data) {
|
|
kfree(st);
|
|
st = file->private_data;
|
|
goto lost_race;
|
|
}
|
|
/* we haven't lost - check for allocation failure now */
|
|
if (!st) {
|
|
unlock_kernel();
|
|
return POLLIN;
|
|
}
|
|
|
|
/*
|
|
* need to prevent the module from being unloaded, since
|
|
* proc_unregister does not call the release method and
|
|
* we would have a memory leak
|
|
*/
|
|
st->lastev = conndiscevcnt;
|
|
file->private_data = st;
|
|
mask = POLLIN;
|
|
}
|
|
lost_race:
|
|
if (file->f_mode & FMODE_READ)
|
|
poll_wait(file, &deviceconndiscwq, wait);
|
|
if (st->lastev != conndiscevcnt)
|
|
mask |= POLLIN;
|
|
st->lastev = conndiscevcnt;
|
|
unlock_kernel();
|
|
return mask;
|
|
}
|
|
|
|
static int usb_device_open(struct inode *inode, struct file *file)
|
|
{
|
|
file->private_data = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static int usb_device_release(struct inode *inode, struct file *file)
|
|
{
|
|
kfree(file->private_data);
|
|
file->private_data = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static loff_t usb_device_lseek(struct file * file, loff_t offset, int orig)
|
|
{
|
|
loff_t ret;
|
|
|
|
lock_kernel();
|
|
|
|
switch (orig) {
|
|
case 0:
|
|
file->f_pos = offset;
|
|
ret = file->f_pos;
|
|
break;
|
|
case 1:
|
|
file->f_pos += offset;
|
|
ret = file->f_pos;
|
|
break;
|
|
case 2:
|
|
default:
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
unlock_kernel();
|
|
return ret;
|
|
}
|
|
|
|
const struct file_operations usbfs_devices_fops = {
|
|
.llseek = usb_device_lseek,
|
|
.read = usb_device_read,
|
|
.poll = usb_device_poll,
|
|
.open = usb_device_open,
|
|
.release = usb_device_release,
|
|
};
|