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