From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Kleine-Budde Subject: Re: [PATCH v4 4/4] can: kvaser_usb: Retry first bulk transfer on -ETIMEDOUT Date: Mon, 12 Jan 2015 11:25:28 +0100 Message-ID: <54B3A118.5000907@pengutronix.de> References: <20141223154654.GB6460@vivalin-002> <20150111200544.GA8855@linux> <20150111201116.GB8855@linux> <20150111201519.GC8855@linux> <20150111203612.GA8999@linux> <20150111204508.GB8999@linux> <54B2E23E.1090108@pengutronix.de> <20150112101407.GA9213@linux> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="9v9aGvt0WxUxsUVtwToHBBAcGdKSKKAIF" Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:60084 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752319AbbALKZj (ORCPT ); Mon, 12 Jan 2015 05:25:39 -0500 In-Reply-To: <20150112101407.GA9213@linux> Sender: linux-can-owner@vger.kernel.org List-ID: To: "Ahmed S. Darwish" Cc: Olivier Sobrie , Oliver Hartkopp , Wolfgang Grandegger , Greg Kroah-Hartman , Linux-USB , Linux-CAN , netdev , LKML This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --9v9aGvt0WxUxsUVtwToHBBAcGdKSKKAIF Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 01/12/2015 11:14 AM, Ahmed S. Darwish wrote: > On Sun, Jan 11, 2015 at 09:51:10PM +0100, Marc Kleine-Budde wrote: >> On 01/11/2015 09:45 PM, Ahmed S. Darwish wrote: >>> From: Ahmed S. Darwish >>> >>> (This is a draft patch, I'm not sure if this fixes the USB >>> bug or only its psymptom. Feedback from the linux-usb folks >>> is really appreciated.) >>> >>> When plugging the Kvaser USB/CAN dongle the first time, everything >>> works as expected and all of the transfers from and to the USB >>> device succeeds. >>> >>> Meanwhile, after unplugging the device and plugging it again, the >>> first bulk transfer _always_ returns an -ETIMEDOUT. The following >>> behaviour was observied: >>> >>> - Setting higher timeout values for the first bulk transfer never >>> solved the issue. >>> >>> - Unloading, then loading, our kvaser_usb module in question >>> __always__ solved the issue. >>> >>> - Checking first bulk transfer status, and retry the transfer >>> again in case of an -ETIMEDOUT also __always__ solved the issue. >>> This is what the patch below does. >>> >>> - In the testing done so far, this issue appears only on laptops >>> but never on PCs (possibly power related?) >>> >>> Signed-off-by: Ahmed S. Darwish >> >> Does this patch apply apply between 3 and 4? If not, please re-arrange= >> the series. As this is a bug fix, patches 1, 2 and 4 will go via >> net/master, 3 will go via net-next/master. >=20 > Since no one complained earlier, I guess this issue only affects > USBCAN devices. That's why I've based it above patch #3: adding > USBCAN hardware support. >=20 > Nonetheless, it won't do any harm for the current Leaf-only > driver. So _if_ this is the correct fix, I will update the commit > log, refactor the check into a 'do { } while()' loop, and then > base it above the Leaf-only net/master fixes on patch #1, and #2. >=20 > Any feedback on the USB side of things? Maybe you have to change the subject of this patch to be more visible on the USB list and/or add the right USB people on Cc. Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | --9v9aGvt0WxUxsUVtwToHBBAcGdKSKKAIF Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJUs6EYAAoJECte4hHFiupU2FQP/0k3HDCuGX9VlOIC2bGhNSMZ O7h0l9q35wvi6x2nD1mpsv0rNQUYE4HnZkFrq3ci75i6w6PB92KbOwwXrxwr4yZU PwMepf1NLYsocGWVyszBXtsqEx0c1DDBhMA6mh/XI3ouG9kGeIuIKndEIE+1Hs20 oDx0U1dD9buQg7TjKxTq9qlHS/hluLCZx1GRZ4tXDiBgi+VNU7/FfLQ0tYtywTBx fzC6KCn4rAyeVMIIdHNg2me53TJcLw8SVRtkDXbKphZFydTbAWAwhvdsqqxAYr9q abSyySbjfLa+JHS2dgsb7P38NwqAU+O0LuYLJdMPvHG6EK6pAzghe6Ptk0e5qSw4 JkGg5l0+2WWHvfaimZ/WL9SMxOa9J5Uh/X6VUnjl8bwoXFXqCV+iZU0XEADN7IJq m2Gr1EqpX9NooH2MHuXpcnBv3PXzePlj0DAcegqhtlLIHDp0+DLNQPWEH9rxc/7v QfAHPlS5xAidiydAmsbXkxOIu3cuFCsecmmx2tKEnsep1tvQKW9wtjGW5W7mSZ6y pFsLfbDsQSoKtk+mp+IovsS0QDSDdSm2uBlyDxiJTtMC0irOBfWdpa9+t4n8WDNa CogWYL4cG/CrBfTwitb9Qr7WKD8SY5O6N67jbbZ+ELDKm1TiGyrF6UtIQQQoBMJQ zH8xPg8sKWpaY2yt9J4n =AwgF -----END PGP SIGNATURE----- --9v9aGvt0WxUxsUVtwToHBBAcGdKSKKAIF--