[PATCH 3.16 094/136] usb: gadget: udc: atmel: Fix interrupt storm in FIFO mode.

Ben Hutchings
2019-12-17T00:54:13Z

From: Cristian Birsan <cristian.birsan@microchip.com>

commit ba3a1a915c49cc3023e4ddfc88f21e7514e82aa4 upstream.

Fix interrupt storm generated by endpoints when working in FIFO mode.
The TX_COMPLETE interrupt is used only by control endpoints processing.
Do not enable it for other types of endpoints.

Fixes: 914a3f3b3754 ("USB: add atmel_usba_udc driver")
Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/gadget/atmel_usba_udc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/usb/gadget/atmel_usba_udc.c
+++ b/drivers/usb/gadget/atmel_usba_udc.c
@@ -392,9 +392,11 @@ static void submit_request(struct usba_e
next_fifo_transaction(ep, req);
if (req->last_transaction) {
usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY);
- usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
+ if (ep_is_control(ep))
+ usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
} else {
- usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+ if (ep_is_control(ep))
+ usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
usba_ep_writel(ep, CTL_ENB, USBA_TX_PK_RDY);
}
}