From patchwork Tue Feb 19 18:48:43 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herton Ronaldo Krzesinski X-Patchwork-Id: 221792 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id 49D632C0086 for ; Wed, 20 Feb 2013 05:51:39 +1100 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1U7sHr-0004IM-3Z; Tue, 19 Feb 2013 18:51:31 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1U7sHX-000494-Py for kernel-team@lists.ubuntu.com; Tue, 19 Feb 2013 18:51:11 +0000 Received: from [177.16.121.6] (helo=canonical.com) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1U7sHX-00021d-3F; Tue, 19 Feb 2013 18:51:11 +0000 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 20/81] USB: EHCI: fix bug in scheduling periodic split transfers Date: Tue, 19 Feb 2013 15:48:43 -0300 Message-Id: <1361299784-8830-21-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1361299784-8830-1-git-send-email-herton.krzesinski@canonical.com> References: <1361299784-8830-1-git-send-email-herton.krzesinski@canonical.com> X-Extended-Stable: 3.5 Cc: Greg Kroah-Hartman , Alan Stern X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com 3.5.7.6 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit 3e619d04159be54b3daa0b7036b0ce9e067f4b5d upstream. This patch (as1654) fixes a very old bug in ehci-hcd, connected with scheduling of periodic split transfers. The calculations for full/low-speed bus usage are all carried out after the correction for bit-stuffing has been applied, but the values in the max_tt_usecs array assume it hasn't been. The array should allow for allocation of up to 90% of the bus capacity, which is 900 us, not 780 us. The symptom caused by this bug is that any isochronous transfer to a full-speed device with a maxpacket size larger than about 980 bytes is always rejected with a -ENOSPC error. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman Signed-off-by: Herton Ronaldo Krzesinski --- drivers/usb/host/ehci-sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index 33182c6..ccc9f70 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -236,7 +236,7 @@ static inline unsigned char tt_start_uframe(struct ehci_hcd *ehci, __hc32 mask) } static const unsigned char -max_tt_usecs[] = { 125, 125, 125, 125, 125, 125, 30, 0 }; +max_tt_usecs[] = { 125, 125, 125, 125, 125, 125, 125, 25 }; /* carryover low/fullspeed bandwidth that crosses uframe boundries */ static inline void carryover_tt_bandwidth(unsigned short tt_usecs[8])