From 4ee691f6aced74c30bbe15d9e97313df21037ae3 Mon Sep 17 00:00:00 2001
From: Bryan Wu <bryan.wu@analog.com>
Date: Mon, 9 Aug 2010 14:58:24 -0400
Subject: [PATCH] usb: musb: only write CLRDATATOG when appropriate
This is a change similar to what is already in the Linux driver. We
should only program the CLRDATATOG bit when the current mode indicates
that it is needed.
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
drivers/usb/musb/musb_hcd.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/musb/musb_hcd.c b/drivers/usb/musb/musb_hcd.c
index af989aa78d..f38b279096 100644
--- a/drivers/usb/musb/musb_hcd.c
+++ b/drivers/usb/musb/musb_hcd.c
@@ -144,19 +144,28 @@ static void write_toggle(struct usb_device *dev, u8 ep, u8 dir_out)
u16 csr;
if (dir_out) {
- if (!toggle)
- writew(MUSB_TXCSR_CLRDATATOG, &musbr->txcsr);
- else {
- csr = readw(&musbr->txcsr);
+ csr = readw(&musbr->txcsr);
+ if (!toggle) {
+ if (csr & MUSB_TXCSR_MODE)
+ csr = MUSB_TXCSR_CLRDATATOG;
+ else
+ csr = 0;
+ writew(csr, &musbr->txcsr);
+ } else {
csr |= MUSB_TXCSR_H_WR_DATATOGGLE;
writew(csr, &musbr->txcsr);
csr |= (toggle << MUSB_TXCSR_H_DATATOGGLE_SHIFT);
writew(csr, &musbr->txcsr);
}
} else {
- if (!toggle)
- writew(MUSB_RXCSR_CLRDATATOG, &musbr->rxcsr);
- else {
+ if (!toggle) {
+ csr = readw(&musbr->txcsr);
+ if (csr & MUSB_TXCSR_MODE)
+ csr = MUSB_RXCSR_CLRDATATOG;
+ else
+ csr = 0;
+ writew(csr, &musbr->rxcsr);
+ } else {
csr = readw(&musbr->rxcsr);
csr |= MUSB_RXCSR_H_WR_DATATOGGLE;
writew(csr, &musbr->rxcsr);
--
2.39.5