serial 8250: tighten test for using backup timer
authorAlex Williamson <alex.williamson@hp.com>
Mon, 28 Apr 2008 09:14:09 +0000 (02:14 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 28 Apr 2008 15:58:30 +0000 (08:58 -0700)
commit01c194d9278efc15d4785ff205643e9c0bdcef53
treedc2aa404a4cb480f58fbc503bcf5826a3a03f597
parentfc3f341b5a1a3f26ec8ed74a38234db7d0d1bae1
serial 8250: tighten test for using backup timer

Thomas Koeller had reported an issue where a device that had been making use
of the UART_BUG_TXEN code in the 8250 driver was mistakenly being caught by
the backup timer test, causing the device to work improperly.

To fix this, tighten the test requirements to enable the backup timer
workaround.

The backup timer is really meant to catch UARTs that don't re-assert the THRE
interrupt.  The expectation is that they do initially assert THRE.  This patch
clarifies the test.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Cc: Thomas Koeller <thomas@koeller.dyndns.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/serial/8250.c