From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:45801 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752909AbcGYUzb (ORCPT ); Mon, 25 Jul 2016 16:55:31 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrew Goodbody , Bin Liu Subject: [PATCH 3.14 06/53] usb: musb: Stop bulk endpoint while queue is rotated Date: Mon, 25 Jul 2016 13:54:48 -0700 Message-Id: <20160725203514.497080862@linuxfoundation.org> In-Reply-To: <20160725203514.202312855@linuxfoundation.org> References: <20160725203514.202312855@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrew Goodbody commit 7b2c17f829545df27a910e8d82e133c21c9a8c9c upstream. Ensure that the endpoint is stopped by clearing REQPKT before clearing DATAERR_NAKTIMEOUT before rotating the queue on the dedicated bulk endpoint. This addresses an issue where a race could result in the endpoint receiving data before it was reprogrammed resulting in a warning about such data from musb_rx_reinit before it was thrown away. The data thrown away was a valid packet that had been correctly ACKed which meant the host and device got out of sync. Signed-off-by: Andrew Goodbody Signed-off-by: Bin Liu Signed-off-by: Greg Kroah-Hartman --- drivers/usb/musb/musb_host.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -950,9 +950,15 @@ static void musb_bulk_nak_timeout(struct if (is_in) { dma = is_dma_capable() ? ep->rx_channel : NULL; - /* clear nak timeout bit */ + /* + * Need to stop the transaction by clearing REQPKT first + * then the NAK Timeout bit ref MUSBMHDRC USB 2.0 HIGH-SPEED + * DUAL-ROLE CONTROLLER Programmer's Guide, section 9.2.2 + */ rx_csr = musb_readw(epio, MUSB_RXCSR); rx_csr |= MUSB_RXCSR_H_WZC_BITS; + rx_csr &= ~MUSB_RXCSR_H_REQPKT; + musb_writew(epio, MUSB_RXCSR, rx_csr); rx_csr &= ~MUSB_RXCSR_DATAERROR; musb_writew(epio, MUSB_RXCSR, rx_csr);