From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yingjoe Chen Subject: Re: [PATCH RESEND] i2c: mediatek: disable zero-length transfers for mt8183 Date: Thu, 22 Aug 2019 16:24:38 +0800 Message-ID: <1566462278.26641.1.camel@mtksdaap41> References: <20190822055737.142384-1-hsinyi@chromium.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190822055737.142384-1-hsinyi@chromium.org> Sender: linux-kernel-owner@vger.kernel.org To: Hsin-Yi Wang Cc: Wolfram Sang , linux-arm-kernel@lists.infradead.org, Nicolas Boichat , Alexandru M Stan , Jun Gao , linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-i2c@vger.kernel.org, Matthias Brugger , Thomas Gleixner , Qii Wang List-Id: linux-i2c@vger.kernel.org On Thu, 2019-08-22 at 13:57 +0800, Hsin-Yi Wang wrote: > When doing i2cdetect quick write mode, we would get transfer > error ENOMEM, and i2cdetect shows there's no device at the address. > Quoting from mt8183 datasheet, the number of transfers to be > transferred in one transaction should be set to bigger than 1, > so we should forbid zero-length transfer and update functionality. <...> > @@ -933,8 +942,8 @@ static int mtk_i2c_probe(struct platform_device *pdev) > i2c->dev = &pdev->dev; > i2c->adap.dev.parent = &pdev->dev; > i2c->adap.owner = THIS_MODULE; > - i2c->adap.algo = &mtk_i2c_algorithm; > i2c->adap.quirks = i2c->dev_comp->quirks; > + i2c->adap.algo = &mtk_i2c_algorithm; > i2c->adap.timeout = 2 * HZ; > i2c->adap.retries = 1; > Why do you need to change this part? Joe.C