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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 B8913C43613 for ; Mon, 24 Jun 2019 06:47:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8CF5420820 for ; Mon, 24 Jun 2019 06:47:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561358874; bh=Z5He2uD9MlfIuLNKbxZIoYtCPRvHPO8k/v21KJxmYq0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=IbIaa3AzmOtioOGGHQprrntFKsCXqCrwyfAaRxlBlBO5HqTJZ3zF+LJgEskZCbh87 mOoR4A+pKc5iKQNZkuFLUd/MDcG5cGZlrMS9bchAh1725FM5qGktl97tMCXJI21vmN R+RV2A0ZFppCCL0WkN2MUa4ACtOZgn9sgtuNx9hw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726820AbfFXGry (ORCPT ); Mon, 24 Jun 2019 02:47:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:41110 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726416AbfFXGry (ORCPT ); Mon, 24 Jun 2019 02:47:54 -0400 Received: from localhost (unknown [106.201.35.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 337C120674; Mon, 24 Jun 2019 06:47:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561358872; bh=Z5He2uD9MlfIuLNKbxZIoYtCPRvHPO8k/v21KJxmYq0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=2QViUH+qEgmWJE4F5AvyDe6LvRqsgIt/PZ6vBKyrfY6vaFVugDnxfpJZvAd+hgVH2 iYZAucOQcIWIlVYGa2lnod/6QZkAnL1Zuf3EIHDkEodkglJmQFnKDv8f7umchVx4jH xhYjd+JM+YtMIPmUUKJyPCR/t2Zmy2qHSwUOXYKQ= Date: Mon, 24 Jun 2019 12:14:42 +0530 From: Vinod Koul To: jassisinghbrar@gmail.com Cc: dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, orito.takao@socionext.com, masami.hiramatsu@linaro.org, kasai.kazuhiro@socionext.com, Jassi Brar Subject: Re: [PATCH 2/2] dmaengine: milbeaut-hdmac: Add HDMAC driver for Milbeaut platforms Message-ID: <20190624064442.GW2962@vkoul-mobl> References: <20190613005109.1867-1-jassisinghbrar@gmail.com> <20190613005247.2048-1-jassisinghbrar@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190613005247.2048-1-jassisinghbrar@gmail.com> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 12-06-19, 19:52, jassisinghbrar@gmail.com wrote: > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include Do we need both, IIRC of_dma.h does include of.h! > +/* mc->vc.lock must be held by caller */ > +static void milbeaut_chan_start(struct milbeaut_hdmac_chan *mc, > + struct milbeaut_hdmac_desc *md) > +{ > + struct scatterlist *sg; > + u32 cb, ca, src_addr, dest_addr, len; ^^ double space > +static irqreturn_t milbeaut_hdmac_interrupt(int irq, void *dev_id) > +{ > + struct milbeaut_hdmac_chan *mc = dev_id; > + struct milbeaut_hdmac_desc *md; > + irqreturn_t ret = IRQ_HANDLED; > + u32 val; > + > + spin_lock(&mc->vc.lock); > + > + /* Ack and Disable irqs */ > + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACB); > + val &= ~(FIELD_PREP(MLB_HDMAC_SS, 0x7)); ^^^^ Magic ..? > +static int milbeaut_hdmac_chan_pause(struct dma_chan *chan) > +{ > + struct virt_dma_chan *vc = to_virt_chan(chan); > + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); > + u32 val; > + > + spin_lock(&mc->vc.lock); > + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACA); > + val |= MLB_HDMAC_PB; > + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACA); We really should have an updatel() and friends in kernel, feel free to add in your driver though! > +static int milbeaut_hdmac_chan_init(struct platform_device *pdev, > + struct milbeaut_hdmac_device *mdev, > + int chan_id) > +{ > + struct device *dev = &pdev->dev; > + struct milbeaut_hdmac_chan *mc = &mdev->channels[chan_id]; > + char *irq_name; > + int irq, ret; > + > + irq = platform_get_irq(pdev, chan_id); > + if (irq < 0) { > + dev_err(&pdev->dev, "failed to get IRQ number for ch%d\n", > + chan_id); > + return irq; > + } > + > + irq_name = devm_kasprintf(dev, GFP_KERNEL, "milbeaut-hdmac-%d", > + chan_id); > + if (!irq_name) > + return -ENOMEM; > + > + ret = devm_request_irq(dev, irq, milbeaut_hdmac_interrupt, > + IRQF_SHARED, irq_name, mc); I tend to dislike using devm_request_irq(), we have no control over when the irq is freed and what is a spirious irq is running while we are unrolling, so IMHO it make sense to free up and ensure all tasklets are quiesced when remove returns > + if (ret) > + return ret; > + > + mc->mdev = mdev; > + mc->reg_ch_base = mdev->reg_base + MLB_HDMAC_CH_STRIDE * (chan_id + 1); > + mc->vc.desc_free = milbeaut_hdmac_desc_free; > + vchan_init(&mc->vc, &mdev->ddev); who kills the vc->task? > +static int milbeaut_hdmac_remove(struct platform_device *pdev) > +{ > + struct milbeaut_hdmac_device *mdev = platform_get_drvdata(pdev); > + struct dma_chan *chan; > + int ret; > + > + /* > + * Before reaching here, almost all descriptors have been freed by the > + * ->device_free_chan_resources() hook. However, each channel might > + * be still holding one descriptor that was on-flight at that moment. > + * Terminate it to make sure this hardware is no longer running. Then, > + * free the channel resources once again to avoid memory leak. > + */ > + list_for_each_entry(chan, &mdev->ddev.channels, device_node) { > + ret = dmaengine_terminate_sync(chan); > + if (ret) > + return ret; > + milbeaut_hdmac_free_chan_resources(chan); > + } > + > + of_dma_controller_free(pdev->dev.of_node); > + dma_async_device_unregister(&mdev->ddev); > + clk_disable_unprepare(mdev->clk); And as suspected we have active tasklets and irq at this time :( -- ~Vinod