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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F1E4DC433F5 for ; Wed, 17 Nov 2021 05:10:44 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id ABBE361A03 for ; Wed, 17 Nov 2021 05:10:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org ABBE361A03 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BE1CF6E1D2; Wed, 17 Nov 2021 05:10:43 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id B26366E1D2 for ; Wed, 17 Nov 2021 05:10:42 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id B13C66187F; Wed, 17 Nov 2021 05:10:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637125842; bh=YAWYlbsffL0+V+TDNFAwJ7WXF7SeHKdpZnj811euHtI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=npGFUrADa2IMYN9GEaNkt/aEHsR/P5aDG3yl9cwUaZRsYC12H6s0oCpLfHvR3vq90 mc/X4mEbR2mUJh1N8GVdTC5UtZO5bpCjmIIKAsBIiDI/d7saXY9ooU4tVPNrl8+Gvi iV0GGiALIL1N2U2v3Gy9HFy9DwsUZfGdUdpu2KbkbMBfJj5zGQV3ivofpkUr25kYxf yfp/S/POujotodSlAESXx0tWoAGY9KwlU6CLbjUzIN+kWkAmNrNbSmjFyuKISZA9Ju SiWhZcxOzcZx1XOIX7PcyZjsSqUvq1VHJ3xKKwPr78vMkaqrjwvUzOL6GgXQ+NNoic 8ZQaEi9rsg3aA== Date: Wed, 17 Nov 2021 10:40:38 +0530 From: Vinod Koul To: John Stultz Subject: Re: [PATCH] lontium-lt9611: check a different register bit for HDMI sensing Message-ID: References: <20211117020724.2647769-1-pcc@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Anibal Limon , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Bjorn Andersson , Robert Foss , Peter Collingbourne Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi John, On 16-11-21, 20:47, John Stultz wrote: > On Tue, Nov 16, 2021 at 6:07 PM Peter Collingbourne wrote: > > > > It has been observed that with certain monitors such as the HP Z27n, > > the register 0x825e reads a value of 0x79 when the HDMI cable is > > connected and 0x78 when it is disconnected, i.e. bit 0 appears > > to correspond to the HDMI connection status and bit 2 is never > > set. Therefore, change the driver to check bit 0 instead of bit 2. > > > > Signed-off-by: Peter Collingbourne > > Link: https://linux-review.googlesource.com/id/I7e76411127e1ce4988a3f6d0c8ba5f1c3d880c23 > > --- > > N.B. I don't currently have easy access to a monitor that works > > with the existing driver, so it would be great if people with > > monitors that currently work could test this patch to make sure > > that it doesn't introduce any regressions. Otherwise I will change > > it to check both bits. > > So very interesting! I gave this a spin with my monitors and it works fine. > > Vinod: Can you check the datasheet to see if the wrong bit is being used here? Well the document I have does not list this register :( I have asked Lontium folks about this register description, will update if I hear back. Meanwhile we can get this patch tested with different monitors. Thanks -- ~Vinod 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68BCCC433EF for ; Wed, 17 Nov 2021 05:10:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A10E613D0 for ; Wed, 17 Nov 2021 05:10:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230236AbhKQFNl (ORCPT ); Wed, 17 Nov 2021 00:13:41 -0500 Received: from mail.kernel.org ([198.145.29.99]:34222 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229801AbhKQFNk (ORCPT ); Wed, 17 Nov 2021 00:13:40 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B13C66187F; Wed, 17 Nov 2021 05:10:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637125842; bh=YAWYlbsffL0+V+TDNFAwJ7WXF7SeHKdpZnj811euHtI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=npGFUrADa2IMYN9GEaNkt/aEHsR/P5aDG3yl9cwUaZRsYC12H6s0oCpLfHvR3vq90 mc/X4mEbR2mUJh1N8GVdTC5UtZO5bpCjmIIKAsBIiDI/d7saXY9ooU4tVPNrl8+Gvi iV0GGiALIL1N2U2v3Gy9HFy9DwsUZfGdUdpu2KbkbMBfJj5zGQV3ivofpkUr25kYxf yfp/S/POujotodSlAESXx0tWoAGY9KwlU6CLbjUzIN+kWkAmNrNbSmjFyuKISZA9Ju SiWhZcxOzcZx1XOIX7PcyZjsSqUvq1VHJ3xKKwPr78vMkaqrjwvUzOL6GgXQ+NNoic 8ZQaEi9rsg3aA== Date: Wed, 17 Nov 2021 10:40:38 +0530 From: Vinod Koul To: John Stultz Cc: Peter Collingbourne , Robert Foss , Anibal Limon , Bjorn Andersson , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] lontium-lt9611: check a different register bit for HDMI sensing Message-ID: References: <20211117020724.2647769-1-pcc@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi John, On 16-11-21, 20:47, John Stultz wrote: > On Tue, Nov 16, 2021 at 6:07 PM Peter Collingbourne wrote: > > > > It has been observed that with certain monitors such as the HP Z27n, > > the register 0x825e reads a value of 0x79 when the HDMI cable is > > connected and 0x78 when it is disconnected, i.e. bit 0 appears > > to correspond to the HDMI connection status and bit 2 is never > > set. Therefore, change the driver to check bit 0 instead of bit 2. > > > > Signed-off-by: Peter Collingbourne > > Link: https://linux-review.googlesource.com/id/I7e76411127e1ce4988a3f6d0c8ba5f1c3d880c23 > > --- > > N.B. I don't currently have easy access to a monitor that works > > with the existing driver, so it would be great if people with > > monitors that currently work could test this patch to make sure > > that it doesn't introduce any regressions. Otherwise I will change > > it to check both bits. > > So very interesting! I gave this a spin with my monitors and it works fine. > > Vinod: Can you check the datasheet to see if the wrong bit is being used here? Well the document I have does not list this register :( I have asked Lontium folks about this register description, will update if I hear back. Meanwhile we can get this patch tested with different monitors. Thanks -- ~Vinod