[PATCH 3.11 063/131] usb: chipidea: need to mask when writting endptflush and endptprime

Luis Henriques luis.henriques at canonical.com
Wed Mar 5 14:23:07 UTC 2014


3.11.10.6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Matthieu CASTET <matthieu.castet at parrot.com>

commit 5bf5dbeda2454296f1984adfbfc8e6f5965ac389 upstream.

ENDPTFLUSH and ENDPTPRIME registers are set by software and clear
by hardware. There is a bit for each endpoint. When we are setting
a bit for an endpoint we should make sure we do not touch other
endpoint bit. There is a race condition if the hardware clear the
bit between the read and the write in hw_write.

Signed-off-by: Peter Chen <peter.chen at freescale.com>
Signed-off-by: Matthieu CASTET <matthieu.castet at parrot.com>
Tested-by: Michael Grzeschik <mgrzeschik at pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/chipidea/udc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index 3a223a8..b13fc29 100644
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -103,7 +103,7 @@ static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
 
 	do {
 		/* flush any pending transfer */
-		hw_write(ci, OP_ENDPTFLUSH, BIT(n), BIT(n));
+		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
 			cpu_relax();
 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
@@ -203,7 +203,7 @@ static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
 		return -EAGAIN;
 
-	hw_write(ci, OP_ENDPTPRIME, BIT(n), BIT(n));
+	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
 
 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
 		cpu_relax();
-- 
1.9.0





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