USB OHCI issue
Hi everybody,
I am currently playing around with U-Boot's (PCI) OHCI driver on a 405 board. U-Boot's USB stuff is running fine on this board. I can read files from an USB stick without any problems.
But when I start Linux with a (rather old) 2.4.21 kernel, the still connected USB stick is not detected as storage device. I have two ways to get USB working under this Linux kernel:
a) I do not start the USB subsystem at the U-Boot prompt ('usb start')
b) I disconnect and reconnect the USB stick when Linux is running.
Both options are not really what I want. Calling 'usb stop' before booting Linux does not help.
I am not sure if this is a Linux or U-Boot issue. Perhaps a newer kernel does not show this issue, but upgrading is currently not an option:-)
Can anybody verify this behavior with other 2.4.x kernels?
Regards
Matthias
Hi Matthias,
Quoted 9 lines · Matthias Fuchs
I am currently playing around with U-Boot's (PCI) OHCI driver on a 405 board. U-Boot's USB stuff is running fine on this board. I can read files from an USB stick without any problems.
But when I start Linux with a (rather old) 2.4.21 kernel, the still connected USB stick is not detected as storage device. I have two ways to get USB working under this Linux kernel:
a) I do not start the USB subsystem at the U-Boot prompt ('usb start')
So maybe USB does not get stopped completely when "usb stop" is issued. Are you using the generic USB driver (CONFIG_USB_OHCI_NEW) ? Maybe you need some board dependant code to correctly stop USB?
Quoted 1 line
b) I disconnect and reconnect the USB stick when Linux is running.
So the kernel doesn't get notified of the already plugged device if it has been started under U-Boot. I suppose this supports the theory of "usb stop" not working.
I would try to find why :-)
Best regards
Markus Klotzbuecher
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