From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07765C433FE for ; Tue, 30 Nov 2021 10:03:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240584AbhK3KGn (ORCPT ); Tue, 30 Nov 2021 05:06:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49514 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240736AbhK3KGc (ORCPT ); Tue, 30 Nov 2021 05:06:32 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98E75C06175B; Tue, 30 Nov 2021 02:03:06 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id A22F1CE185A; Tue, 30 Nov 2021 10:03:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B4CFC53FC7; Tue, 30 Nov 2021 10:03:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638266582; bh=/x0GGzKFVt0Dy7r4zIhS59DKhLpLSCOv6TfyEvgAn/E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aiu3DAfh8MthxvWAwRpRhPEHK7GTD+ROtg4Dm6dvj0giFP+oAyQUQur5meks8hFGP xuoAtkqMJU7VwQOPbx31xQwgPdJ0+dqObWX30klV/fxaYpUJd1uxc3uuXN6efBS6t8 qUf7xqXNNwIEhUchAaROr2KK0DqSjkUkxLr6cn1oBAjecy1FeMXbdsY5XGuDJKWubv cMOhPNvXlMq/NAdBslnbglXQvN8JZYemEbx+uDKiEVgmQ57wjqZJK+6hGy4YJ/CNNc vT+Yp2G1ct1I++ZlivOFy/AFf8+7eG88Vfgh17aIeLPuf6VzqN/6CGaw+a2S2Ch+im 4/FQP9oDaLUdg== Date: Tue, 30 Nov 2021 11:02:59 +0100 From: Wolfram Sang To: Quan Nguyen Cc: Corey Minyard , Rob Herring , Joel Stanley , Andrew Jeffery , Brendan Higgins , Benjamin Herrenschmidt , openipmi-developer@lists.sourceforge.net, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, Open Source Submission , Phong Vo , "Thang Q . Nguyen" Subject: Re: [PATCH v5 1/3] i2c: aspeed: Add slave_enable() to toggle slave mode Message-ID: Mail-Followup-To: Wolfram Sang , Quan Nguyen , Corey Minyard , Rob Herring , Joel Stanley , Andrew Jeffery , Brendan Higgins , Benjamin Herrenschmidt , openipmi-developer@lists.sourceforge.net, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, Open Source Submission , Phong Vo , "Thang Q . Nguyen" References: <20210714033833.11640-1-quan@os.amperecomputing.com> <20210714033833.11640-2-quan@os.amperecomputing.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="GLgFZVkdCWguog1a" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --GLgFZVkdCWguog1a Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, > Thanks Wolfram to help bring this up, Sure thing! It would be sad to see this work bitrot. > This driver was tested with Aspeed ast2500 and we have tried many way to > avoid using slave_enable() to toggle slave mode but there is no progress. I see. I also can't help you there. I have neither experience with nor access to this HW. > Our expectation is still to have this driver upstream'ed and I'm thinking > about testing this driver on other HW and re-post the driver. That sounds like a good plan. > I have to admit that you are all right with the above comments. The fact = is > we still not be able to find any way to solve this differently. We don't = own > this HW and dont know what happen on this particular issue. The SCL clock > stretching on this HW does not work as expected and the slave_enable() is > the only solution for now. I hope if someone could help with the issue as > well. =46rom this distance, it looks like HW access and a logic analyzer might be helpful in understanding the behaviour. Pity that you don't own the HW. Good luck nonetheless! Wolfram --GLgFZVkdCWguog1a Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmGl9tAACgkQFA3kzBSg Kba4dA/+LQ+TgyjbUYOZOjpRRji7agnQYuqCWgQAJb0L8O9WQWEaoPwlAYP2DpHP WdVIVnuLhRvwWKSI2yNAJRZURY4fbvrSAXFoeyY1DrxxLVj7GB4Ku9dKGUQEu8vk SufpI4wpozucy32ZHAY8sDlquSILlCHEchyb8851rfbBWKBhQfKwNtO+vwEYqcy6 UqEp1wxYUV0WpXCDiGXb3m+qViyb84t54YzBSHzKvBFYyRi1S94BESgQ3W2XVRPA BGwy+uhgF32jeBFs6wdv+zCpq+NBmAZg/czXt2naPF6HkNjG4ZTMgROmqoery36M VEuhlE6us23UVcCDujArrFcH1+qhhTYSAOxZZ9qDSWYmsxxF0k/fHi55bszcCoyE Ba3OFUe8TKMfYARMkjpRtN60aLtq/E7M+X1/774Q2BUvvS9UVUMs5jK7umQsuJ/3 7BZIFiXT1RKExUKxD5dHVyCXnO6AoF1t3aNZlqlgo9IDmWhQeyfqM+oHwBjqINYD hmLL3djjgpe9DksOXDFu17ywiSB33+OvfWhO502tbDrv+QxIbsIR4G+wffxcUG+b Ts8pgy7y+6cdNxLvrpUv+SjzATHxRmwWuTGNr8hlgxtckDybKKkWeEmQLdIlrVYg Y24ut60ocJP+alOr+eP2bqQDyNqx+ARwSFBP6FKA+04ASyeNrro= =qe3w -----END PGP SIGNATURE----- --GLgFZVkdCWguog1a-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 49C71C433EF for ; Tue, 30 Nov 2021 10:21:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=iM7NDZmIEZQT965SKgTnTURHoOG1tGBvqZhbqF34yHA=; b=Ri5IOmNazBLwHllklJm3khuYCc LEFVd8zY/0x2WtuAgXlkqNtutXKMQYb6m1r13oCSbhD0MFXoH6O+sZ4PvENC8RPrYG2TwrGP3JEFQ Ia8L6L4Vt4NWGCZOdg6hlrD41fkKvsA7rqhx7MLWHnMoEU377r1icjd6KjezhDM8hQYEdRs0EpCfD 0Hse+TJePP4+WOP1GHrcL0j3zQ9m9bOFWBGOzuG0RbSsVBIFfNwSvVs0RdMR3vTcONOrJR40vWhIk MGPswujBgzkIQm6gXdF0QiDg42pWfYa+hj4TwZx6lYRRWm5hbVurPUxxW7cNdaPy33iGBK7WBqlhs wpnxvjwA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ms0EV-004Z2z-3Y; Tue, 30 Nov 2021 10:19:31 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mrzyb-004U1v-2K for linux-arm-kernel@lists.infradead.org; Tue, 30 Nov 2021 10:03:06 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 4476ECE1872; Tue, 30 Nov 2021 10:03:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B4CFC53FC7; Tue, 30 Nov 2021 10:03:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638266582; bh=/x0GGzKFVt0Dy7r4zIhS59DKhLpLSCOv6TfyEvgAn/E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aiu3DAfh8MthxvWAwRpRhPEHK7GTD+ROtg4Dm6dvj0giFP+oAyQUQur5meks8hFGP xuoAtkqMJU7VwQOPbx31xQwgPdJ0+dqObWX30klV/fxaYpUJd1uxc3uuXN6efBS6t8 qUf7xqXNNwIEhUchAaROr2KK0DqSjkUkxLr6cn1oBAjecy1FeMXbdsY5XGuDJKWubv cMOhPNvXlMq/NAdBslnbglXQvN8JZYemEbx+uDKiEVgmQ57wjqZJK+6hGy4YJ/CNNc vT+Yp2G1ct1I++ZlivOFy/AFf8+7eG88Vfgh17aIeLPuf6VzqN/6CGaw+a2S2Ch+im 4/FQP9oDaLUdg== Date: Tue, 30 Nov 2021 11:02:59 +0100 From: Wolfram Sang To: Quan Nguyen Cc: Corey Minyard , Rob Herring , Joel Stanley , Andrew Jeffery , Brendan Higgins , Benjamin Herrenschmidt , openipmi-developer@lists.sourceforge.net, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, Open Source Submission , Phong Vo , "Thang Q . Nguyen" Subject: Re: [PATCH v5 1/3] i2c: aspeed: Add slave_enable() to toggle slave mode Message-ID: Mail-Followup-To: Wolfram Sang , Quan Nguyen , Corey Minyard , Rob Herring , Joel Stanley , Andrew Jeffery , Brendan Higgins , Benjamin Herrenschmidt , openipmi-developer@lists.sourceforge.net, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, Open Source Submission , Phong Vo , "Thang Q . Nguyen" References: <20210714033833.11640-1-quan@os.amperecomputing.com> <20210714033833.11640-2-quan@os.amperecomputing.com> MIME-Version: 1.0 In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211130_020305_504963_64297DF3 X-CRM114-Status: GOOD ( 19.93 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7589033444332683654==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============7589033444332683654== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="GLgFZVkdCWguog1a" Content-Disposition: inline --GLgFZVkdCWguog1a Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, > Thanks Wolfram to help bring this up, Sure thing! It would be sad to see this work bitrot. > This driver was tested with Aspeed ast2500 and we have tried many way to > avoid using slave_enable() to toggle slave mode but there is no progress. I see. I also can't help you there. I have neither experience with nor access to this HW. > Our expectation is still to have this driver upstream'ed and I'm thinking > about testing this driver on other HW and re-post the driver. That sounds like a good plan. > I have to admit that you are all right with the above comments. The fact = is > we still not be able to find any way to solve this differently. We don't = own > this HW and dont know what happen on this particular issue. The SCL clock > stretching on this HW does not work as expected and the slave_enable() is > the only solution for now. I hope if someone could help with the issue as > well. =46rom this distance, it looks like HW access and a logic analyzer might be helpful in understanding the behaviour. Pity that you don't own the HW. Good luck nonetheless! Wolfram --GLgFZVkdCWguog1a Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmGl9tAACgkQFA3kzBSg Kba4dA/+LQ+TgyjbUYOZOjpRRji7agnQYuqCWgQAJb0L8O9WQWEaoPwlAYP2DpHP WdVIVnuLhRvwWKSI2yNAJRZURY4fbvrSAXFoeyY1DrxxLVj7GB4Ku9dKGUQEu8vk SufpI4wpozucy32ZHAY8sDlquSILlCHEchyb8851rfbBWKBhQfKwNtO+vwEYqcy6 UqEp1wxYUV0WpXCDiGXb3m+qViyb84t54YzBSHzKvBFYyRi1S94BESgQ3W2XVRPA BGwy+uhgF32jeBFs6wdv+zCpq+NBmAZg/czXt2naPF6HkNjG4ZTMgROmqoery36M VEuhlE6us23UVcCDujArrFcH1+qhhTYSAOxZZ9qDSWYmsxxF0k/fHi55bszcCoyE Ba3OFUe8TKMfYARMkjpRtN60aLtq/E7M+X1/774Q2BUvvS9UVUMs5jK7umQsuJ/3 7BZIFiXT1RKExUKxD5dHVyCXnO6AoF1t3aNZlqlgo9IDmWhQeyfqM+oHwBjqINYD hmLL3djjgpe9DksOXDFu17ywiSB33+OvfWhO502tbDrv+QxIbsIR4G+wffxcUG+b Ts8pgy7y+6cdNxLvrpUv+SjzATHxRmwWuTGNr8hlgxtckDybKKkWeEmQLdIlrVYg Y24ut60ocJP+alOr+eP2bqQDyNqx+ARwSFBP6FKA+04ASyeNrro= =qe3w -----END PGP SIGNATURE----- --GLgFZVkdCWguog1a-- --===============7589033444332683654== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============7589033444332683654==--