From patchwork Sat Jan 15 08:06:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe JAILLET X-Patchwork-Id: 532389 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11D02C433F5 for ; Sat, 15 Jan 2022 08:06:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232651AbiAOIGi (ORCPT ); Sat, 15 Jan 2022 03:06:38 -0500 Received: from smtp03.smtpout.orange.fr ([80.12.242.125]:54838 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230309AbiAOIGh (ORCPT ); Sat, 15 Jan 2022 03:06:37 -0500 Received: from pop-os.home ([90.126.236.122]) by smtp.orange.fr with ESMTPA id 8e55niL4YhTNk8e55n3jsu; Sat, 15 Jan 2022 09:06:36 +0100 X-ME-Helo: pop-os.home X-ME-Auth: YWZlNiIxYWMyZDliZWIzOTcwYTEyYzlhMmU3ZiQ1M2U2MzfzZDfyZTMxZTBkMTYyNDBjNDJlZmQ3ZQ== X-ME-Date: Sat, 15 Jan 2022 09:06:36 +0100 X-ME-IP: 90.126.236.122 From: Christophe JAILLET To: Mathias Nyman , Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Christophe JAILLET , linux-usb@vger.kernel.org Subject: [PATCH] usb: host: xhci-plat: Remove useless DMA-32 fallback configuration Date: Sat, 15 Jan 2022 09:06:31 +0100 Message-Id: <178f859197bebb385609a7c9458fb972ed312e5d.1642233968.git.christophe.jaillet@wanadoo.fr> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org As stated in [1], dma_set_mask() with a 64-bit mask never fails if dev->dma_mask is non-NULL. So, if it fails, the 32 bits case will also fail for the same reason. Simplify code and remove some dead code accordingly. [1]: https://lore.kernel.org/linux-kernel/YL3vSPK5DXTNvgdx@infradead.org/#t Signed-off-by: Christophe JAILLET --- The "if (ret)" is also useless because dma_coerce_mask_and_coherent(..., 64) + dma_set_mask_and_coherent(..., 64) can't fail according to [1]. However, I've left it as-is because it is a common pattern. It could be replaced by a comment explaining why, but looks like an overkill to me. --- drivers/usb/host/xhci-plat.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index c1edcc9b13ce..93b321682b35 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -226,20 +226,13 @@ static int xhci_plat_probe(struct platform_device *pdev) if (!sysdev) sysdev = &pdev->dev; - /* Try to set 64-bit DMA first */ if (WARN_ON(!sysdev->dma_mask)) /* Platform did not initialize dma_mask */ - ret = dma_coerce_mask_and_coherent(sysdev, - DMA_BIT_MASK(64)); + ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64)); else ret = dma_set_mask_and_coherent(sysdev, DMA_BIT_MASK(64)); - - /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */ - if (ret) { - ret = dma_set_mask_and_coherent(sysdev, DMA_BIT_MASK(32)); - if (ret) - return ret; - } + if (ret) + return ret; pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev);