From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jernej =?utf-8?B?xaBrcmFiZWM=?= Subject: Re: [PATCH 2/6] dmaengine: sun6i: Add a quirk for additional mbus clock Date: Sat, 16 Mar 2019 12:23:47 +0100 Message-ID: <2451376.qVWA8nfu3q@jernej-laptop> References: <20190307165829.9086-1-jernej.skrabec@siol.net> <20190307165829.9086-3-jernej.skrabec@siol.net> <20190316110753.GH5348@vkoul-mobl> Reply-To: jernej.skrabec-gGgVlfcn5nU@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org In-Reply-To: <20190316110753.GH5348@vkoul-mobl> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Vinod Koul Cc: maxime.ripard-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org, wens-jdAy2FN1RRM@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org List-Id: devicetree@vger.kernel.org Hi! Dne sobota, 16. marec 2019 ob 12:07:53 CET je Vinod Koul napisal(a): > On 07-03-19, 17:58, Jernej Skrabec wrote: > > H6 DMA controller needs additional mbus clock to be enabled. > > > > Add a quirk for it and handle it accordingly. > > > > Signed-off-by: Jernej Skrabec > > --- > > > > drivers/dma/sun6i-dma.c | 23 ++++++++++++++++++++++- > > 1 file changed, 22 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c > > index 0cd13f17fc11..761555080325 100644 > > --- a/drivers/dma/sun6i-dma.c > > +++ b/drivers/dma/sun6i-dma.c > > @@ -129,6 +129,7 @@ struct sun6i_dma_config { > > > > u32 dst_burst_lengths; > > u32 src_addr_widths; > > u32 dst_addr_widths; > > > > + bool mbus_clk; > > > > }; > > > > /* > > > > @@ -182,6 +183,7 @@ struct sun6i_dma_dev { > > > > struct dma_device slave; > > void __iomem *base; > > struct clk *clk; > > > > + struct clk *clk_mbus; > > So rather than have mbus_clk and then a ptr, why not use the ptr and use > NULL value to check for..? > I'm not sure what you mean here. clk_mbus will hold a reference to a clock retrieved by devm_clk_get() so it has to be "struct clk *". What I'm missing here? > > int irq; > > spinlock_t lock; > > struct reset_control *rstc; > > > > @@ -1208,6 +1210,14 @@ static int sun6i_dma_probe(struct platform_device > > *pdev)> > > return PTR_ERR(sdc->clk); > > > > } > > > > + if (sdc->cfg->mbus_clk) { > > where is the populated? I was expecting this to be set based on DT! Of course it is based on DT. Check patch 5, where quirks structure attached to H6 DMA compatible contains ".mbus_clk = true,". "sdc->cfg" points to this quirk structure. > > > + sdc->clk_mbus = devm_clk_get(&pdev->dev, "mbus"); > > + if (IS_ERR(sdc->clk_mbus)) { > > + dev_err(&pdev->dev, "No mbus clock specified\n"); > > + return PTR_ERR(sdc->clk_mbus); > > + } > > + } > > + > > > > sdc->rstc = devm_reset_control_get(&pdev->dev, NULL); > > if (IS_ERR(sdc->rstc)) { > > > > dev_err(&pdev->dev, "No reset controller specified\n"); > > > > @@ -1312,11 +1322,19 @@ static int sun6i_dma_probe(struct platform_device > > *pdev)> > > goto err_reset_assert; > > > > } > > > > + if (sdc->cfg->mbus_clk) { > > + ret = clk_prepare_enable(sdc->clk_mbus); > > + if (ret) { > > + dev_err(&pdev->dev, "Couldn't enable mbus clock\n"); > > + goto err_clk_disable; > > + } > > + } > > + > > > > ret = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0, > > > > dev_name(&pdev->dev), sdc); > > > > if (ret) { > > > > dev_err(&pdev->dev, "Cannot request IRQ\n"); > > > > - goto err_clk_disable; > > + goto err_mbus_clk_disable; > > > > } > > > > ret = dma_async_device_register(&sdc->slave); > > > > @@ -1341,6 +1359,8 @@ static int sun6i_dma_probe(struct platform_device > > *pdev)> > > dma_async_device_unregister(&sdc->slave); > > > > err_irq_disable: > > sun6i_kill_tasklet(sdc); > > > > +err_mbus_clk_disable: > > + clk_disable_unprepare(sdc->clk_mbus); > > > > err_clk_disable: > > clk_disable_unprepare(sdc->clk); > > > > err_reset_assert: > > @@ -1359,6 +1379,7 @@ static int sun6i_dma_remove(struct platform_device > > *pdev)> > > sun6i_kill_tasklet(sdc); > > > > + clk_disable_unprepare(sdc->clk_mbus); > > > > clk_disable_unprepare(sdc->clk); > > reset_control_assert(sdc->rstc);