Jeff says: > I'm trying to access the serial port ttyS2 that is set in the BIOS as > "OS Controlled" without much success. If it's set it to "Always > Enabled", I can access the serial port. > This is on the Intermec CV60, and ttyS2 is the touchscreen port. > # setserial /dev/ttyS2 > /dev/ttyS2, UART: 16550A, Port: 0x03e8, IRQ: 6 > If I set the BIOS to "OS Controlled", I can't access the serial port > no matter what parameter I pass to the setserial. The factory default > is "OS Controlled", and Window XP can detect and access the port. and found that this is enough to enable it: > echo "auto" > /sys/bus/pnp/devices/00:0a/resources My guess (with no evidence) is that running _SRS enables the device, and that Windows does that automatically but Linux doesn't. I think it's a bug that Linux doesn't make this port work automatically.
Created attachment 68572 [details] dmesg log
Created attachment 68582 [details] DSDT (disassembled)
A patch referencing this bug report has been merged in Linux v3.1-rc4: commit ab8ba3a2d2cba6a658ef596cd5b2e0905b6c8a9f Author: Bjorn Helgaas <bhelgaas@google.com> Date: Tue Aug 16 12:02:28 2011 -0600 serial: 8250_pnp: add Intermec CV60 touchscreen device
Hmm, what's the status of this bug? Does the problem still exists in the latest upstream kernel?
Fixed. commit ab8ba3a2d2cba6a658ef596cd5b2e0905b6c8a9f Author: Bjorn Helgaas <bhelgaas@google.com> Date: Tue Aug 16 12:02:28 2011 -0600 serial: 8250_pnp: add Intermec CV60 touchscreen device It would have been nice if Intermec had supplied a PNP0501 _CID for the COM3 device, but they didn't, so we have to recognize it explicitly. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=40612 CC: Jeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable <stable@kernel.org> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Good to know. Bug closed.