Messages in this thread | | | From | John Mock <> | Subject | USB driver troubles: OHCI vs. UHCI | Date | Tue, 02 Mar 2004 18:30:37 -0800 |
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I've been using a homebrew USB driver for a PIC microprocessor development board (Microchip PICkit, which uses the HID 'knothole'), based the 2.4.21 USB skeleton driver (with a few minor changes) for many months now on a PowerMac 8500 with an add-on OHCI board. I tried compiling for a Sony VAIO R505EL, which uses the UHCI driver, with poor results.
Under 2.4.22, it works the first time the device is opened, but hangs on subsequent operations until the device is power cycled or the UHCI driver is module is removed/re-installed again.
I tried updating it to 2.6.1-rc2 and it quickly gets an error, saying
[skel]_write - failed submitting write urb, error -22.
Thinking i had messed up the driver, i generated a current kernel (2.6.3) on the PowerMac, and the updated driver worked the first time with the OHCI board.
Is this a known problem with 2.6.xx, and if so, what does it mean??
Any idea what the skeleton driver isn't doing under 2.4.2x which causes a device to enter a hung state on subsequent opens on UCHI (but not OHCI)?
As of a few minutes ago, i have a workaround. But i'm still quite puzzled and hope someone else has been here before.
-- JM - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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