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=-6.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 81A14C33CB1 for ; Thu, 16 Jan 2020 16:37:05 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 56E602073A for ; Thu, 16 Jan 2020 16:37:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="p/EGIvUA"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="EJLTwp2Z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 56E602073A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=NW+/vxjkP43ZCPr5oY/OLYYFzWlD+6XQEdxJ6ijwi8c=; b=p/EGIvUAd5hSC9 AQA0enOo8HQvw6iylU7eAIDwYR2EnMOAfkUvdD1OBXBXsb7DF6TdCvjJimBepQYS1uoDYzE5rwqSH Yym0Wgd2lRWdlluWMKLjCsyLnmIsOgHJj7lBxLMWFv5dvpFQSzyruyqc10/9VEBg1HKBqbEEbtxRG OOw7snN6i5Oy1WdZlPDBPmiY6Ynj6I7ZwMkKjCrkrfEZNzwl59Rl3vNHZMh2XD2ZycAlCDnqaZwWQ k9nC37zzu0bUdKBaCxgAfrkzq4bXhRp/ojucJ8sz+9Q0LXNZJzts7G3/lf024BCi+dA8yEcDKj5pG K/HJIGnofoKMrm6tRQ2Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1is88a-0003sd-I4; Thu, 16 Jan 2020 16:36:52 +0000 Received: from mail-il1-x141.google.com ([2607:f8b0:4864:20::141]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1is88V-0003rn-2i; Thu, 16 Jan 2020 16:36:51 +0000 Received: by mail-il1-x141.google.com with SMTP id t8so18748478iln.4; Thu, 16 Jan 2020 08:36:45 -0800 (PST) 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=F5CUZisbEmcuPSU1emkEgklMu7uKE46FRb40awhcNNw=; b=EJLTwp2ZhMt6m8MIODOMxX8F0WUxZXnFllgPy0vjYRaP2a/uqLd7VgfSGrWmo8hpAJ NPHIjFIJGRLr4oNAz9tf5hOsdcfuVYMnqjiTf2J4RCADCuxQW+oGSsB83s4QcMRYpoPy vf1DpVdQTI/VdvN2YcvhWNwF4XaXJSfsa0NNO5bimCUjbA5cJJ6NJWxgsXS2WESS+fUM XotHwzWPyWBYZMI9ssGzm7k30A7uRYYqAYpyL23ouh5EW6o0lP2Rp5LvXf14sfItRsni tEMr9QVNKomtq9S+mvxD/frcA8S1mOvx2byWGDSjpzIyfdwenphPtbBOjb3rbGha0prQ SK/g== 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=F5CUZisbEmcuPSU1emkEgklMu7uKE46FRb40awhcNNw=; b=l9qkSbgsM0VYhHsSgUFVk18q95MzBIU30ozE674B4CrHPCL0ZtfjxccU4y7eOZQ654 ApgVnagnDVdp7fnp5j7yu/8pE/ZmRcMbTftLChuZz7G8RKLGW1r/qxKFVQ4whQAgjlI/ zboxa2T8rpvkaxJcGEvHP8BOGJyPIQVo7iEa5pGhewVLb/aEN+zLsVipLZdNQCkXLkYT +4CfCnj7MJNicsd/O4RN+ygtd/4KqkfJ5uhMx1sNfT2ggxhA/04cuomqoNk8VBC+vF/e 2qF4KnJsK69lB9d0v3XpJKMsGdXz8LdzZ5uXurOFUzkMMHsAn55MolumT/rvK++JtHcM nuuQ== X-Gm-Message-State: APjAAAXXF6DtdiirjnCz8jPA8hDBUJiZG526gx7NJi+JB8Ph5de72aTs EILoiNXuB1jg1V6S/nEjSfGsnMt+zk/q1pr0Bak= X-Google-Smtp-Source: APXvYqxwMlno7wjUoiFGxFWb2n/ehu6lv/LisVmo7tUhvmCPmOwoAt13VzXh6hngJWSHaeNKOw/agO1BB94B4lZ59eo= X-Received: by 2002:a92:3d17:: with SMTP id k23mr4375754ila.110.1579192605275; Thu, 16 Jan 2020 08:36:45 -0800 (PST) MIME-Version: 1.0 References: <1579038243-28550-1-git-send-email-han.xu@nxp.com> <1579038243-28550-4-git-send-email-han.xu@nxp.com> <20200115080257.dtd4vss4uhopbvn2@pengutronix.de> In-Reply-To: <20200115080257.dtd4vss4uhopbvn2@pengutronix.de> From: Han Xu Date: Thu, 16 Jan 2020 10:36:33 -0600 Message-ID: Subject: Re: [PATCH 3/6] dmaengine: mxs: add the power management functions To: Sascha Hauer X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200116_083647_124550_3C09DF3A X-CRM114-Status: GOOD ( 19.68 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vignesh Raghavendra , Richard Weinberger , Esben Haabendal , linux-kernel@vger.kernel.org, Shawn Guo , vkoul@kernel.org, Boris Brezillon , linux-mtd , linux-imx@nxp.com, Miquel Raynal , dmaengine@vger.kernel.org, Han Xu , Fabio Estevam , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Wed, Jan 15, 2020 at 2:03 AM Sascha Hauer wrote: > > On Wed, Jan 15, 2020 at 05:44:00AM +0800, Han Xu wrote: > > add the power management functions and leverage the runtime pm for > > system suspend/resume > > > > Signed-off-by: Han Xu > > --- > > drivers/dma/mxs-dma.c | 97 +++++++++++++++++++++++++++++++++++++++---- > > 1 file changed, 90 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c > > index b458f06f9067..251492c5ea58 100644 > > --- a/drivers/dma/mxs-dma.c > > +++ b/drivers/dma/mxs-dma.c > > @@ -25,6 +25,7 @@ > > #include > > #include > > #include > > +#include > > > > #include > > > > @@ -39,6 +40,8 @@ > > #define dma_is_apbh(mxs_dma) ((mxs_dma)->type == MXS_DMA_APBH) > > #define apbh_is_old(mxs_dma) ((mxs_dma)->dev_id == IMX23_DMA) > > > > +#define MXS_DMA_RPM_TIMEOUT 50 /* ms */ > > + > > #define HW_APBHX_CTRL0 0x000 > > #define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29) > > #define BM_APBH_CTRL0_APB_BURST_EN (1 << 28) > > @@ -416,6 +419,7 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan) > > { > > struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan); > > struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma; > > + struct device *dev = &mxs_dma->pdev->dev; > > int ret; > > > > mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev, > > @@ -431,9 +435,11 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan) > > if (ret) > > goto err_irq; > > > > - ret = clk_prepare_enable(mxs_dma->clk); > > - if (ret) > > + ret = pm_runtime_get_sync(dev); > > + if (ret < 0) { > > + dev_err(dev, "Failed to enable clock\n"); > > goto err_clk; > > From looking at other DMA drivers I know we are in good company here, > but I think this is wrong. Doing pm_runtime_get_sync() in > alloc_chan_resources() and going to autosuspend in free_chan_resources() > effectively disables runtime_pm as clients normally acquire their > channels during driver probe and release them only in driver remove. Thanks for the comments. That's why I moved acquire_dma_resource from the probe to runtime_resume in the gpmi driver, this change won't disable the runtime_pm function and the incremental counter always balanced. > > In the next patch you release the DMA channels in the GPMI nand drivers > runtime_suspend hook just to somehow trigger the runtime_suspend of the > DMA driver. > > What you should do instead is to make sure the hook runtime_pm to the > DMA drivers activity phases, like for example the pl330 driver does. > Then you wouldn't have to care about manually putting the DMA driver into > suspend from the GPMI NAND driver. > > Sascha > > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ -- Sincerely, Han XU ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/