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 X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D777C4338F for ; Thu, 19 Aug 2021 09:10:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2087F60EFE for ; Thu, 19 Aug 2021 09:10:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237435AbhHSJK6 (ORCPT ); Thu, 19 Aug 2021 05:10:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229804AbhHSJK5 (ORCPT ); Thu, 19 Aug 2021 05:10:57 -0400 Received: from mail-il1-x12e.google.com (mail-il1-x12e.google.com [IPv6:2607:f8b0:4864:20::12e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41A7AC061575 for ; Thu, 19 Aug 2021 02:10:21 -0700 (PDT) Received: by mail-il1-x12e.google.com with SMTP id y3so5247352ilm.6 for ; Thu, 19 Aug 2021 02:10:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=lZ3CToCG3juWBo4uXSiPR3dQNTGtjH08RmsNnVvcEdM=; b=GlsyqZ60mR4Jb195DNR0iUo8ZVyc+xbfTqPuxCN8jKL0SocJ2mcD3cEczU0+RNSVtp /2POP99Dyqv45MqZLx95Xm8RJm1+kHsIieRWMHgUQip3hTYqMKIeMjHT0+j5OKRwDP5K 5RYLzwpIOOWETVntPXHk0mVF+IYSKgVo1u2Z/V9bHzw55Y6MFaAcxSM1Yu7mByszsxyq Z8PRnt2BAMZ7bZtluCP32IK0MihUm8b4GhWUVNaat0EOndartBjt579la/MfngAgrkEt TN/6H1dj2Vfh/BePaSQflMl7fZ3XLbm1fQMyIiYO7XTonjoX7/72D7znc95GWzf08TlC M02w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=lZ3CToCG3juWBo4uXSiPR3dQNTGtjH08RmsNnVvcEdM=; b=MZhpOem7OUmEhgwf/P4amwHFyYjRCPm5vM9/Q67L2M4Gh8iY7QczRUuwNywwbSUjri ay+pHGE3dAKNQiMglILkkBSzrxvGO1VT5sKQTYHiKRi1wqs/7iJMrOpbbcR5FozBSyMq UCHw9qNt13RL8wCsPGQhLvnuHE4sVr+JdBIcv8X30ShtcDl3xAnZJ9DcriKGuXk5zYL3 a6Wjit19XM6uKNx9Ec9mdUJLcZt5l1v6DkBmpwosGYryUx4nMUrxOICCCxm7GiMrfktr TizKo4RbAmAnZYFKr5xzShFiZp9aYBNbijTWQZ4PMqIxWj47nEgNl2s0nYwdHlbkKnZN Hbvw== X-Gm-Message-State: AOAM532lbMg7kSBgrPygSrU2Qrk/MyKG/0C+cE/dAHXP9/v+UEag1mTj 5kd6W8/7N3GK0glV3SnmGKv3/Ddq2G7MTQ7KZt4= X-Google-Smtp-Source: ABdhPJzWrgxLb164lORkiiVfIZ8tsSObzJ0sWkzhyZvsCUTgz2Qg7BH9GY8iQrX1/DlFXdoSgu6ZeOF45h/oPFgnEsQ= X-Received: by 2002:a92:6802:: with SMTP id d2mr8918753ilc.40.1629364220674; Thu, 19 Aug 2021 02:10:20 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Alistair Francis Date: Thu, 19 Aug 2021 19:10:00 +1000 Message-ID: Subject: Re: Revert "video: fbdev: mxsfb: Remove driver" To: Sam Ravnborg Cc: Marek Vasut , Fabio Estevam , Shawn Guo , Sascha Hauer , dl-linux-imx , b.zolnierkie@samsung.com, Linux Kernel Mailing List , Alistair Francis Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 19, 2021 at 4:38 AM Sam Ravnborg wrote: > > Hi Alistair, > > > > > These are the EINVAL strace tells me in the not working case: > > > > prctl(PR_CAPBSET_READ, 0x30 /* CAP_??? */) = -1 EINVAL (Invalid argument) > > prctl(PR_CAPBSET_READ, 0x2c /* CAP_??? */) = -1 EINVAL (Invalid argument) > > prctl(PR_CAPBSET_READ, 0x2a /* CAP_??? */) = -1 EINVAL (Invalid argument) > > prctl(PR_CAPBSET_READ, 0x29 /* CAP_??? */) = -1 EINVAL (Invalid argument) > > ioctl(5, FBIOPUT_VSCREENINFO, 0x4ce8e0) = -1 EINVAL (Invalid argument) > > > > I'm guessing it's related to FBIOPUT_VSCREENINFO then, is that > > something that could be added to the DRM emulation? > > If it turns out FBIOPUT_VSCREENINFO is the culprint it would also be > good to know why we see EINVAL. > One way is to sprinkle a number of printk's in fb_set_var(), > then you can see how far you get before it fails. Thanks for the help. I see this line: ret = info->fbops->fb_check_var(var, info); in fb_set_var() returning early. Alistair > > This could hopefully give a clue why this fails with fbdev emulation. > > Sam