From: Russell King - ARM Linux Subject: Re: [PATCH 43/51] DMA-API: dma: edma.c: no need to explicitly initialize DMA masks Date: Mon, 23 Sep 2013 12:37:55 +0100 Message-ID: <20130923113755.GT25647@n2100.arm.linux.org.uk> References: <20130919212235.GD12758@n2100.arm.linux.org.uk> <20130923102533.GI17188@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: alsa-devel@alsa-project.org, linux-doc@vger.kernel.org, linux-mmc@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-nvme@lists.infradead.org, linux-ide@vger.kernel.org, devel@driverdev.osuosl.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, e1000-devel@lists.sourceforge.net, b43-dev@lists.infradead.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org, Dan Williams , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Solarflare linux maintainers , netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, linux-crypto@vger.kernel.org, uclinux-dist-devel@blackfin.uclinux.org, linuxppc-dev@lists.ozlabs.org To: Vinod Koul Return-path: Content-Disposition: inline In-Reply-To: <20130923102533.GI17188@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org List-Id: linux-crypto.vger.kernel.org On Mon, Sep 23, 2013 at 03:55:33PM +0530, Vinod Koul wrote: > On Fri, Sep 20, 2013 at 12:15:39AM +0100, Russell King wrote: > > register_platform_device_full() can setup the DMA mask provided the > > appropriate member is set in struct platform_device_info. So lets > > make that be the case. This avoids a direct reference to the DMA > > masks by this driver. > > > > Signed-off-by: Russell King > Acked-by: Vinod Koul > > This also brings me question that should we force the driver to use the > dma_set_mask_and_coherent() API or they have below flexiblity too? There's two issues here: 1. dma_set_mask_and_coherent() will only work if dev->dma_mask points at some storage for the mask. This needs to have .dma_mask in the platform_device_info initialised. 2. Yes, this driver should also be calling the appropriate DMA mask setting functions in addition to having the mask initialized at device creation time. Here's a replacement patch, though maybe it would be better to roll all the additions of dma_set_mask_and_coherent() in drivers/dma into one patch? In other words, combine the addition of this with these two patches: dma: pl330: add dma_set_mask_and_coherent() call dma: pl08x: add dma_set_mask_and_coherent() call 8<===== From: Russell King Subject: [PATCH] DMA-API: dma: edma.c: no need to explicitly initialize DMA masks register_platform_device_full() can setup the DMA mask provided the appropriate member is set in struct platform_device_info. So lets make that be the case. This avoids a direct reference to the DMA masks by this driver. While here, add the dma_set_mask_and_coherent() call which the DMA API requires DMA-using drivers to call. Signed-off-by: Russell King --- drivers/dma/edma.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index ff50ff4..fd5e48c 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -631,6 +631,10 @@ static int edma_probe(struct platform_device *pdev) struct edma_cc *ecc; int ret; + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (ret) + return ret; + ecc = devm_kzalloc(&pdev->dev, sizeof(*ecc), GFP_KERNEL); if (!ecc) { dev_err(&pdev->dev, "Can't allocate controller\n"); @@ -702,11 +706,13 @@ static struct platform_device *pdev0, *pdev1; static const struct platform_device_info edma_dev_info0 = { .name = "edma-dma-engine", .id = 0, + .dma_mask = DMA_BIT_MASK(32), }; static const struct platform_device_info edma_dev_info1 = { .name = "edma-dma-engine", .id = 1, + .dma_mask = DMA_BIT_MASK(32), }; static int edma_init(void) @@ -720,8 +726,6 @@ static int edma_init(void) ret = PTR_ERR(pdev0); goto out; } - pdev0->dev.dma_mask = &pdev0->dev.coherent_dma_mask; - pdev0->dev.coherent_dma_mask = DMA_BIT_MASK(32); } if (EDMA_CTLRS == 2) { @@ -731,8 +735,6 @@ static int edma_init(void) platform_device_unregister(pdev0); ret = PTR_ERR(pdev1); } - pdev1->dev.dma_mask = &pdev1->dev.coherent_dma_mask; - pdev1->dev.coherent_dma_mask = DMA_BIT_MASK(32); } out: -- 1.7.4.4