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 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: Matthieu CASTET <matthieu.castet@xxxxxxxxxx>
---
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 69d20fb..9e2e39b 100644
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -105,7 +105,7 @@ 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)));
@@ -205,7 +205,7 @@ 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();
--
1.8.5.2
--
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