[Xen-changelog] [xen-unstable] ns16550: More robust check for presence of FIFO

[Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1248796057 -3600
# Node ID 0532b32701f85179020e3df06e7485ec3d3cdc4a
# Parent  6ba0f519a9fa1bc9fc4dbb6b644186aa2967b46a
ns16550: More robust check for presence of FIFO

Signed-off-by: Christoph Egger <Christoph.Egger@xxxxxxx>
---
 xen/drivers/char/ns16550.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletion(-)

diff -r 6ba0f519a9fa -r 0532b32701f8 xen/drivers/char/ns16550.c
--- a/xen/drivers/char/ns16550.c        Tue Jul 28 16:43:50 2009 +0100
+++ b/xen/drivers/char/ns16550.c        Tue Jul 28 16:47:37 2009 +0100
@@ -214,7 +214,8 @@ static void __devinit ns16550_init_preir
     ns_write_reg(uart, FCR, FCR_ENABLE | FCR_CLRX | FCR_CLTX | FCR_TRG14);
 
     /* Check this really is a 16550+. Otherwise we have no FIFOs. */
-    if ( (ns_read_reg(uart, IIR) & 0xc0) == 0xc0 )
+    if ( ((ns_read_reg(uart, IIR) & 0xc0) == 0xc0) &&
+         ((ns_read_reg(uart, FCR) & FCR_TRG14) == FCR_TRG14) )
         port->tx_fifo_size = 16;
 }
 

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog