From patchwork Sat Feb 17 14:00:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 10226197 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7092C601D4 for ; Sat, 17 Feb 2018 14:04:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4F02128C1F for ; Sat, 17 Feb 2018 14:04:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 413A328C55; Sat, 17 Feb 2018 14:04:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C1D6828C1F for ; Sat, 17 Feb 2018 14:04:19 +0000 (UTC) Received: from localhost ([::1]:53208 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1en368-0006gK-Oe for patchwork-qemu-devel@patchwork.kernel.org; Sat, 17 Feb 2018 09:04:16 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46097) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1en34w-0005mi-Qf for qemu-devel@nongnu.org; Sat, 17 Feb 2018 09:03:03 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1en34s-0003nM-W8 for qemu-devel@nongnu.org; Sat, 17 Feb 2018 09:03:02 -0500 Received: from mail-lf0-x243.google.com ([2a00:1450:4010:c07::243]:41499) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1en34s-0003mv-Ot for qemu-devel@nongnu.org; Sat, 17 Feb 2018 09:02:58 -0500 Received: by mail-lf0-x243.google.com with SMTP id f136so7584084lff.8 for ; Sat, 17 Feb 2018 06:02:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=8g3VeqEBLLwqmfKajkLXAjgCGS5xAsK+XOXYyEJ1460=; b=dOU9yWnir0EXOfz7y+eTCzB69MQ8/P36ZIFoRc627FHtQ1pOoMW6GEmXp5j4/8mMTV x8qCxqNqtHpdhZcOB0bcY+6kE/bFtxDB6Q2+sWhfBuQZL1HVdxQrMNRk/+UJ2pHytlsg kOO1HnMB6mmp/VVoSLmlvVJBa/IY4Q1La58KM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=8g3VeqEBLLwqmfKajkLXAjgCGS5xAsK+XOXYyEJ1460=; b=ZDpHCDDX/yzWeaowFTvik3VK8Yg28ap7qhO0tGfFxPY5ybTxA7IDyXHk8ByU16sae7 jKiS32722+0qCdEbyRGC8C0lfUhqPTLk9desTrKKwbFJXAQcur6zc53rM3wg80T+8Vgk +dzsKor5ApNrJbUqt6cVIK/7oS+Sc8uwtcKX0C//cOfwSJreX4TiwhzTDmpGs+NWeG+c iVmZXf9iOFKw+LDP/KkAPCs8yldazMicVPQeNQt15C/PlUC3YyPgJ7Vxg6amLFLumHvL kSHkU/83Ns49CRyEYRU7uzI4X2zy1NMuilyVHwKs7oo5Wo2kiyXDIWHCdBEHxKl5r72r QrVw== X-Gm-Message-State: APf1xPDBqaRlUXOnYWT004U/VJ9y2n7CEbrVFJsd+cC8d73qxavJb3Tz uZV1UbWFNr2vMnDK1+NN7u3Sag7c8uo= X-Google-Smtp-Source: AH8x227wIEcil4E69vmS+W/RjhYq3GG4c10Tkg/rKaxMEqHAVV9j8IFc5PDNgQkXnWOfynGPIGbilA== X-Received: by 10.25.74.205 with SMTP id x196mr6647950lfa.46.1518876176796; Sat, 17 Feb 2018 06:02:56 -0800 (PST) Received: from localhost.localdomain (c-cb7471d5.014-348-6c756e10.cust.bredbandsbolaget.se. [213.113.116.203]) by smtp.gmail.com with ESMTPSA id w204sm122054lff.29.2018.02.17.06.02.55 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 17 Feb 2018 06:02:55 -0800 (PST) From: Linus Walleij To: qemu-devel@nongnu.org Date: Sat, 17 Feb 2018 15:00:49 +0100 Message-Id: <20180217140051.22731-1-linus.walleij@linaro.org> X-Mailer: git-send-email 2.14.3 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2a00:1450:4010:c07::243 Subject: [Qemu-devel] [PATCH 1/3] hw/i2c-ddc: Do not fail writes X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linus Walleij , qemu-arm@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The tx function of the DDC I2C slave emulation was returning 1 on all writes resulting in NACK in the I2C bus. Changing it to 0 makes the DDC I2C work fine with bit-banged I2C such as the versatile I2C. I guess it was not affecting whatever I2C controller this was used with until now, but with the Versatile I2C it surely does not work. Signed-off-by: Linus Walleij Reviewed-by: Peter Maydell --- hw/i2c/i2c-ddc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/i2c/i2c-ddc.c b/hw/i2c/i2c-ddc.c index 199dac9e41c1..bec0c91e2dd0 100644 --- a/hw/i2c/i2c-ddc.c +++ b/hw/i2c/i2c-ddc.c @@ -259,12 +259,12 @@ static int i2c_ddc_tx(I2CSlave *i2c, uint8_t data) s->reg = data; s->firstbyte = false; DPRINTF("[EDID] Written new pointer: %u\n", data); - return 1; + return 0; } /* Ignore all writes */ s->reg++; - return 1; + return 0; } static void i2c_ddc_init(Object *obj)