USB Weirdness

[Ian]

I have a Neuros, which is a 20 GB MP3/Ogg player. It connects to the computer using USB 1.1 (fine for me, because that's all I have), and acts as a Mass Storage Device, and a program in portage, called Positron, can build a database that the Neuros can read.

I'm having trouble keeping my Neuros mounted though. I can mount it once, but if I unmount it at all, I must reboot before I can remount it. Yesterday I didn't have this problem, and I don't know what changed to cause this problem.

If I try to mount the Neuros now, it will tell me that /dev/sda does not exist, which is the same error I get if I try to mount it and it is not plugged into the USB port. I have no idea where to even start, but this is a very annoying problem, if I must restart just to load new music onto my Neuros.

Lastly, I'm 99.9% sure it is not the Neuros, because it switches to it's sync screen, and is ready to accept any connection, but the computer isn't recognizing it, or something. Any ideas?

[NeddySeagoon]

Ian,

As Gentoo uses devfs, /dev/sda, which is where your Neuros appears, is made and deleted when the device is detected as added or removed.

It takes a few seconds for 'hotplug' to do its thing though.

You can beat the system by plugging in the Neuros and issuing the mount command before hotplug has made /dev/sda.

Before you remove the device be sure to wait for umount to return, as the data to be written may well be in buffers in main memory until then.

Regards,

NeddySeagoon
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[Z?]

You might just need to remove the usb-storage driver, and reload it. I've got a similar problem with a USB ZIP drive, and that usually solves the problem for me.

I've got a script that backs up my MySQL databases daily to the ZIP drive, and one of the first things I do is unload the sg, sd_mod, and usb-storage modules, and then reload them. Dunno why, but it works. &shrug&

[Ian]

Neddy:

That isn't the case, as I'm not using any hotplug software, it's just the simple USB mass storage driver. From what I've seen, the system detects a mass storage device, creates /dev/sda, and then I can mount it. As to remaining data in the memory, I use the "sync" option, which writes everything to disk before, not hold it in memory until unmounting. Plus, I can tell by gkrellm2 and the Neuros unit when data has stopped going.

Z?:

I made a monolithic kernel because I'm a lazy bum. It's about time I upgraded it though, to the latest mm sources, so I'll try that later if I can. Thanks .

[Ian]

Ok, upgraded to 2.6.0-mm6, and now USB is mounted read-only. This is not only annoying, but shouldn't happen at all based on /etc/fstab.

Any ideas?

<EDIT>
This may be due to the Neuros crashing, and my not noticing.

In other news, what modules do I need to make, and what steps must I take to load and unload them? I'm still getting this same stupid error, and it makes absolutely no sense and is beginning to piss me off greatly, but since I've never needed to use modules before, I have no idea where to start (besides going and hitting M instead of Y).
</EDIT>

[Ian]

Me, once again.

Ok, after a weekend of me tearing out my hair and throwing my keyboard into the wall, all the evidence points to the kernel, specifically the usb/scsi drivers, just seemingly randomly dying on me, and not undying until I reboot.

I have no idea what I did to make this happen, nor how to fix it, except possibly go back to 2.4 for the time being, which i'd rather not do.

[NeddySeagoon]

Ian,

to make a kernel to play with, do the following:-

Save a copy of /usr/src/linux/.config somewhere, so you can get back to your old configuration whenever you like. (Really you should copy the who;e source tree to ~ and make the changes there.)

run make xconfig - it much nicer than make menuconfig.
configure to your liking. Don't go overboard with modules, since everything you need to boot, like the filesystem drivers must be compiled in.

Edit /usr/src/linux/Makefile and change EXTRAVERSION at the top of the file. This will ensure that the modules for this kernel get their own directory in /lib/modules

Do the make dep ... make modules
Do make modules_install
Mount /boot, when you copy the bzImage across, rename it.

Put a new setion in /boot/grub/grub.conf (or /etc/lilo.conf) to point to the new kernel. Now you will have a choice to boot. If your new kernel won't start, you can always go back to the old one.

To load modules on startup, put the module names in /etc/modules.autoload
To load or unload modules manually use /sbin/modprobe
See also lsmod, insmod and rmmod.

Regards,

NeddySeagoon
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[toojays]

Ian,

I just wanted to update this post to say I'm experiencing a similar problem to you with my Neuros, but it's perhaps more intermittent than you (doesn't happen every time to me). I think it's a conflict between the Neuros and some USB driver, as in the Neuros is probably broken, but I consider the software to be broken as well if it can be hung by the hardware.

Hopefully between the two of us fiddling with kernel options we can find something that works.

For reference I have: K7S5A motherboard, kernel 2.4.20-gentoo-r7, using the usb-ohci driver.

[rbeagle]

I just got a Neuros the other day, and I was experiencing the exact same problem. Whenever I'd unmount the Neuros, there would be a kernel OOPS and the block device would disappear from /dev. I haven't tracked down the exact reason that's causing this, but I do know that this problem would happen on EVERY version of the 2.6 kernel I tried. Switching to my old 2.4.20 vanilla kernel solved the problem for me. I guess that's why it's still called beta. It's a shame, I liked 2.6.