Hi I have set up rules in udev. I have 4 hid devices, all them works except one. I did not understand why, but I have done workaround. The issue is that libusb-0.9 expects file in /dev/bus/usb/001/001 to be O_RDWR, and errors out if not the case, so I allowed O_RDONLY in libusb which solves the issue in libusb/os/linux_usbfs.c. I don't understand why libusb always reads from /dev/bus/001/001 instead of /dev/bus/002/001 which is more recent entry. I have removed my device several times but it cached that info of HID device. If I change the permission to allow O_RDONLY, this problem goes away. Please let the dev path having read only permission to use the device. All the permission I set are correct but the caching is issue, we need to disable caching in libusb.
Thanks Amruth p.v --- On Thu, 8/28/08, Lou <[EMAIL PROTECTED]> wrote: > From: Lou <[EMAIL PROTECTED]> > Subject: Re: [Libusb-devel] permission denied for opening HID device > To: "amruth" <[EMAIL PROTECTED]> > Cc: "Marian Aldenhoevel" <[EMAIL PROTECTED]>, "Charles Lepple" <[EMAIL > PROTECTED]>, [EMAIL PROTECTED], "libhid-discuss List" > <[email protected]> > Date: Thursday, August 28, 2008, 1:58 PM > On Tue, Aug 26, 2008 at 05:32:33PM -0700, amruth wrote: > > Hi > > I am using libusb-0.9.2 and libcompat-0.1-beta with > libhid-0.1. > > I am facing this problem whenever I am trying to open > my HID device. > > libusb is always trying to open from > > libusb could'nt open USB device > /dev/bus/usb/001/001 permission denied. > > I have unplugged the HID device several times but > libusb is always trying open from /dev/bus/usb/001/001 > location. Please let me know if anybody has any idea. > > That is a basic permissions problem. Look at the > permissions on that > node. Some folks run their libusb app as root to get > around that, but > that's obviously a security problem. > > A better measure will vary by OS. My system uses udev, so > I created a > udev rule that sets permissions to something else (which I > can access as a > normal user) when that node is created for my particular > device. _______________________________________________ libhid-discuss mailing list [email protected] http://lists.alioth.debian.org/mailman/listinfo/libhid-discuss
