From: Daniel Ritz <daniel.ritz@gmx.ch>

enable read prefetching on O2micro bridges. It fixes the problems
seen with the RME Hammerfall DSP.
Thanks to Eric Still from O2micro for the input.

Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 25-akpm/drivers/pcmcia/i82365.c       |    1 -
 25-akpm/drivers/pcmcia/o2micro.h      |   26 ++++++++++++++++++++++++++
 25-akpm/drivers/pcmcia/yenta_socket.c |   10 +++++++++-
 3 files changed, 35 insertions(+), 2 deletions(-)

diff -puN drivers/pcmcia/i82365.c~pcmcia-enable-read-prefetch-on-o2micro-bridges-to-fix-hdsp drivers/pcmcia/i82365.c
--- 25/drivers/pcmcia/i82365.c~pcmcia-enable-read-prefetch-on-o2micro-bridges-to-fix-hdsp	2004-06-16 00:10:50.438047576 -0700
+++ 25-akpm/drivers/pcmcia/i82365.c	2004-06-16 00:10:50.445046512 -0700
@@ -65,7 +65,6 @@
 #include "cirrus.h"
 #include "vg468.h"
 #include "ricoh.h"
-#include "o2micro.h"
 
 #ifdef DEBUG
 static const char version[] =
diff -puN drivers/pcmcia/o2micro.h~pcmcia-enable-read-prefetch-on-o2micro-bridges-to-fix-hdsp drivers/pcmcia/o2micro.h
--- 25/drivers/pcmcia/o2micro.h~pcmcia-enable-read-prefetch-on-o2micro-bridges-to-fix-hdsp	2004-06-16 00:10:50.439047424 -0700
+++ 25-akpm/drivers/pcmcia/o2micro.h	2004-06-16 00:10:50.445046512 -0700
@@ -120,4 +120,30 @@
 #define  O2_MODE_E_LED_OUT	0x08
 #define  O2_MODE_E_SKTA_ACTV	0x10
 
+static int o2micro_override(struct yenta_socket *socket)
+{
+	/*
+	 * 'reserved' register at 0x94/D4. chaning it to 0xCA (8 bit) enables
+	 * read prefetching which for example makes the RME Hammerfall DSP
+	 * working. for some bridges it is at 0x94, for others at 0xD4. it's
+	 * ok to write to both registers on all O2 bridges.
+	 * from Eric Still, 02Micro.
+	 */
+	if (PCI_FUNC(socket->dev->devfn) == 0) {
+		config_writeb(socket, 0x94, 0xCA);
+		config_writeb(socket, 0xD4, 0xCA);
+	}
+
+	return 0;
+}
+
+static void o2micro_restore_state(struct yenta_socket *socket)
+{
+	/*
+	 * as long as read prefetch is the only thing in
+	 * o2micro_override, it's safe to call it from here
+	 */
+	o2micro_override(socket);
+}
+
 #endif /* _LINUX_O2MICRO_H */
diff -puN drivers/pcmcia/yenta_socket.c~pcmcia-enable-read-prefetch-on-o2micro-bridges-to-fix-hdsp drivers/pcmcia/yenta_socket.c
--- 25/drivers/pcmcia/yenta_socket.c~pcmcia-enable-read-prefetch-on-o2micro-bridges-to-fix-hdsp	2004-06-16 00:10:50.441047120 -0700
+++ 25-akpm/drivers/pcmcia/yenta_socket.c	2004-06-16 00:10:50.447046208 -0700
@@ -668,6 +668,7 @@ static struct pccard_operations yenta_so
 #include "ti113x.h"
 #include "ricoh.h"
 #include "topic.h"
+#include "o2micro.h"
 
 enum {
 	CARDBUS_TYPE_DEFAULT = -1,
@@ -676,7 +677,8 @@ enum {
 	CARDBUS_TYPE_TI12XX,
 	CARDBUS_TYPE_TI1250,
 	CARDBUS_TYPE_RICOH,
-	CARDBUS_TYPE_TOPIC97
+	CARDBUS_TYPE_TOPIC97,
+	CARDBUS_TYPE_O2MICRO,
 };
 
 /*
@@ -716,6 +718,10 @@ struct cardbus_type cardbus_type[] = {
 	[CARDBUS_TYPE_TOPIC97]	= {
 		.override	= topic97_override,
 	},
+	[CARDBUS_TYPE_O2MICRO]	= {
+		.override	= o2micro_override,
+		.restore_state	= o2micro_restore_state,
+	},
 };
 
 
@@ -1100,6 +1106,8 @@ static struct pci_device_id yenta_table 
 	CB_ID(PCI_VENDOR_ID_TOSHIBA, PCI_DEVICE_ID_TOSHIBA_TOPIC97, TOPIC97),
 	CB_ID(PCI_VENDOR_ID_TOSHIBA, PCI_DEVICE_ID_TOSHIBA_TOPIC100, TOPIC97),
 
+	CB_ID(PCI_VENDOR_ID_O2, PCI_ANY_ID, O2MICRO),
+
 	/* match any cardbus bridge */
 	CB_ID(PCI_ANY_ID, PCI_ANY_ID, DEFAULT),
 	{ /* all zeroes */ }
_