Adds ac_timer based polling to the ns16550 UART driver. This is
authorkaf24@firebug.cl.cam.ac.uk <kaf24@firebug.cl.cam.ac.uk>
Thu, 24 Nov 2005 11:06:07 +0000 (12:06 +0100)
committerkaf24@firebug.cl.cam.ac.uk <kaf24@firebug.cl.cam.ac.uk>
Thu, 24 Nov 2005 11:06:07 +0000 (12:06 +0100)
commit0d79c5a9eccaa294a299996203268458b2ce89a3
treed9656ad9bcb97841c264c2146513809a768521f4
parentefb8e0c63f3d394ac37bfeaf3c27cc092d06317f
Adds ac_timer based polling to the ns16550 UART driver.  This is
useful when the interrupt line is not connected in hardware or the
mechanism to enable it is not readily available in the hypervisor.
Polling is only enabled when the UART IRQ is set to zero.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Keir Fraser <keir@xensource.com>
xen/drivers/char/ns16550.c