Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754169AbcDVLMx (ORCPT ); Fri, 22 Apr 2016 07:12:53 -0400 Received: from mx2.suse.de ([195.135.220.15]:43950 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753735AbcDVLGc (ORCPT ); Fri, 22 Apr 2016 07:06:32 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, "Felipe F. Tonello" , Felipe Balbi , Oliver Neukum , Jiri Slaby Subject: [PATCH 3.12 60/78] usb: gadget: f_midi: Fixed a bug when buflen was smaller than wMaxPacketSize Date: Fri, 22 Apr 2016 13:05:43 +0200 Message-Id: <7d4647a410edf0b85529188ac364f365b5a3c7fb.1461323133.git.jslaby@suse.cz> X-Mailer: git-send-email 2.8.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1679 Lines: 54 From: "Felipe F. Tonello" 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 03d27ade4941076b34c823d63d91dc895731a595 upstream. buflen by default (256) is smaller than wMaxPacketSize (512) in high-speed devices. That caused the OUT endpoint to freeze if the host send any data packet of length greater than 256 bytes. This is an example dump of what happended on that enpoint: HOST: [DATA][Length=260][...] DEVICE: [NAK] HOST: [PING] DEVICE: [NAK] HOST: [PING] DEVICE: [NAK] ... HOST: [PING] DEVICE: [NAK] This patch fixes this problem by setting the minimum usb_request's buffer size for the OUT endpoint as its wMaxPacketSize. Acked-by: Michal Nazarewicz Signed-off-by: Felipe F. Tonello Signed-off-by: Felipe Balbi Cc: Oliver Neukum Signed-off-by: Jiri Slaby --- drivers/usb/gadget/f_midi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/f_midi.c b/drivers/usb/gadget/f_midi.c index 263e721c2694..e7f1b967a5bb 100644 --- a/drivers/usb/gadget/f_midi.c +++ b/drivers/usb/gadget/f_midi.c @@ -365,7 +365,9 @@ static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt) /* allocate a bunch of read buffers and queue them all at once. */ for (i = 0; i < midi->qlen && err == 0; i++) { struct usb_request *req = - alloc_ep_req(midi->out_ep, midi->buflen); + alloc_ep_req(midi->out_ep, + max_t(unsigned, midi->buflen, + bulk_out_desc.wMaxPacketSize)); if (req == NULL) return -ENOMEM; -- 2.8.1