Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760696Ab0HEPQM (ORCPT ); Thu, 5 Aug 2010 11:16:12 -0400 Received: from gate.crashing.org ([63.228.1.57]:52414 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933260Ab0HEPQJ (ORCPT ); Thu, 5 Aug 2010 11:16:09 -0400 From: Kumar Gala To: gregkh@suse.de Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , akpm@linux-foundation.org Subject: [PATCH 3/3] powerpc: Dont require a dma_ops struct to set dma mask Date: Thu, 5 Aug 2010 10:15:47 -0500 Message-Id: <1281021347-1278-4-git-send-email-galak@kernel.crashing.org> X-Mailer: git-send-email 1.6.0.6 In-Reply-To: <1281021347-1278-3-git-send-email-galak@kernel.crashing.org> References: <1281021347-1278-1-git-send-email-galak@kernel.crashing.org> <1281021347-1278-2-git-send-email-galak@kernel.crashing.org> <1281021347-1278-3-git-send-email-galak@kernel.crashing.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1762 Lines: 50 The only reason to require a dma_ops struct is to see if it has implemented set_dma_mask. If not we can fall back to setting the mask directly. This resolves an issue with how to sequence the setting of a DMA mask for platform devices. Before we had an issue in that we have no way of setting the DMA mask before the various low level bus notifiers get called that might check it (swiotlb). So now we can do: pdev = platform_device_alloc("foobar", 0); dma_set_mask(&pdev->dev, DMA_BIT_MASK(37)); platform_device_register(pdev); And expect the right thing to happen with the bus notifiers get called via platform_device_register. Signed-off-by: Kumar Gala --- arch/powerpc/include/asm/dma-mapping.h | 6 ++---- 1 files changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h index c85ef23..952208a 100644 --- a/arch/powerpc/include/asm/dma-mapping.h +++ b/arch/powerpc/include/asm/dma-mapping.h @@ -131,12 +131,10 @@ static inline int dma_set_mask(struct device *dev, u64 dma_mask) { struct dma_map_ops *dma_ops = get_dma_ops(dev); - if (unlikely(dma_ops == NULL)) - return -EIO; - if (dma_ops->set_dma_mask != NULL) - return dma_ops->set_dma_mask(dev, dma_mask); if (!dev->dma_mask || !dma_supported(dev, dma_mask)) return -EIO; + if (dma_ops && (dma_ops->set_dma_mask != NULL)) + return dma_ops->set_dma_mask(dev, dma_mask); *dev->dma_mask = dma_mask; return 0; } -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/