From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH V15 4/6] i2c: tegra: Add DMA support Date: Fri, 8 Feb 2019 19:15:20 +0300 Message-ID: <21901823-2ec1-6bd5-d0df-2360858f2b7e@gmail.com> References: <1549576040-15907-1-git-send-email-skomatineni@nvidia.com> <1549576040-15907-4-git-send-email-skomatineni@nvidia.com> <7806f2cd-72b4-6ae3-b75f-0fc74fb62b95@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Sowjanya Komatineni , "thierry.reding@gmail.com" , Jonathan Hunter , Mantravadi Karthik , Shardar Mohammed , Timo Alho Cc: "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-i2c@vger.kernel.org" List-Id: linux-i2c@vger.kernel.org 08.02.2019 18:58, Sowjanya Komatineni пишет: > > >>> Please use "release_dma:" variant that I suggested in the comment to v14 because: >>>> >>> 1) It's just a good (and common-style in kernel) tone to unwind errors handling in the opposite order, it makes code more straight forward and helps to avoid silly mistakes. >>> >>> 2) It keeps the current code consistent in regards to probe error-handling. >>> >> >> Can move tegra_i2c_release_dma under the same disable_div_clk label before clk_disable >> >> Order in probe is > clk_prepare > i2c_runtime_resume > clk_enable in case of multimaster mode > i2c_init_dma >> >> unwinding should be order is > release_dma > disable_div_clk > disable_rpm > unprepared >> >> Probe failure from tegra_i2c_init_dma, tegra_i2c_init, devm_request_irq, i2c_add_numbered_adapter all of them perform goto disable_div_clk >> >> I can add tegra_i2c_release_dma before performing clock disable under same disable_div_clk so all existing disable_div_clk labels remain same. >> Otherwise adding new label release_dma causes all goto disable_div_clk statement also to be changed but its same as adding release_dma under disable_div_clk above the clk_disable. >> > > OK, please ignore above. will add release_dma to show explicitly for readability. > With release_dma all error handlers performing disable_clk_div need to go thru release dma and disable_clk_div label is not needed. tegra_i2c_init_dma() releases dma itself in a case of error, hence it should jump to the disable_clk_div. > So having release dma under disable_clk before clk_disable function is also same. > Please confirm if this is ok to use same disable_div_clk or do you prefer release_dma label removing disable_div_clk In general goto-label naming should reflect the actual jump-action. If goto jumps to dma-releasing, then the action is release-dma and not disable-clk. Hence the correct variant is: diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 7104213d813b..62e81096fb55 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -1604,14 +1604,14 @@ static int tegra_i2c_probe(struct platform_device *pdev) ret = tegra_i2c_init(i2c_dev, false); if (ret) { dev_err(&pdev->dev, "Failed to initialize i2c controller\n"); - goto disable_div_clk; + goto release_dma; } ret = devm_request_irq(&pdev->dev, i2c_dev->irq, tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); - goto disable_div_clk; + goto release_dma; } i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); @@ -1625,14 +1625,16 @@ static int tegra_i2c_probe(struct platform_device *pdev) ret = i2c_add_numbered_adapter(&i2c_dev->adapter); if (ret) - goto disable_div_clk; + goto release_dma; return 0; +release_dma: + tegra_i2c_release_dma(i2c_dev); + disable_div_clk: if (i2c_dev->is_multimaster_mode) clk_disable(i2c_dev->div_clk); - tegra_i2c_release_dma(i2c_dev); disable_rpm: pm_runtime_disable(&pdev->dev);