From patchwork Mon Feb 20 16:09:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Smirnov X-Patchwork-Id: 730086 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3vRpW52MJbz9s9Z for ; Tue, 21 Feb 2017 03:10:09 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="k6wAfanW"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753928AbdBTQKH (ORCPT ); Mon, 20 Feb 2017 11:10:07 -0500 Received: from mail-pg0-f67.google.com ([74.125.83.67]:34198 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754028AbdBTQJx (ORCPT ); Mon, 20 Feb 2017 11:09:53 -0500 Received: by mail-pg0-f67.google.com with SMTP id s67so2926280pgb.1; Mon, 20 Feb 2017 08:09:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=IQAElJh+gHuH7JMAgsRGMzu7WYCYN/OMDoSBFWd1mgU=; b=k6wAfanW7xgcV7xlf7JH2DAfJONFdt1hKeaeuH/woZo4zmyEff6qsEmoC9MPegNKRU Pr6/m84IMgmPhQY+nDKxThQIS7F+rzwnATmf8wQRvQY88KV5Q9GNblbo5NKVNDf/19rx us4sFoXDUK8l/JxAI9vo6bKOmtwHLNwBUuuEquoSoCndxP5q69/jfJe7OjgUWpfCI4oH FbcFByYpUSsbrxPZyrh3UVAsbV6Y5GY0z9TWR7YrNsYAaHXyIS3G2gnMEC/ZlCOftGPq lTPdsoAfSTrNPiPrHxpF49NNIc9r0iz27z914mMJO4O7q4j3XihcBGDhmKu8sxjute3r qLdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=IQAElJh+gHuH7JMAgsRGMzu7WYCYN/OMDoSBFWd1mgU=; b=hrZqio0a0nowREq26ZhdX2l/jesJEnsysCm66244T3JJHR1qyZ0GMYDfsZNedozR9g QPStFVxP0P/Hs7Wnitf0cg7eRMNc025br+fzUMe2440LLYnLxDSu7veGLS6ZMBGxG2We RJA9yxlvtottrJR6wEk02i8AjrjX4t78nbDMPhx1KE44JVJkK5H7oJrGq4+C7zkS8u0Y aZnyHf5ffxZ51IQEMmzfkhMR/z/HEk4fM4ZvEqShyLccIxvz6StQoq/VkmSZIIiAv0LD Afu95XB0aAc3J1GJmscB98hoFsJCFmox1G1vfKqWkoPMyxUVFoNt+Aot48UKbWItJzsb X5gQ== X-Gm-Message-State: AMke39nW1h+FBA8jiQK60i2BY2Tk51Xw6URHgrlDLroV9TGoZeap5DqRERAek+IKaKnUoQ== X-Received: by 10.98.67.72 with SMTP id q69mr26628608pfa.14.1487606992606; Mon, 20 Feb 2017 08:09:52 -0800 (PST) Received: from localhost.localdomain (c-73-19-0-61.hsd1.wa.comcast.net. [73.19.0.61]) by smtp.gmail.com with ESMTPSA id y184sm36059266pfg.86.2017.02.20.08.09.51 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 20 Feb 2017 08:09:52 -0800 (PST) From: Andrey Smirnov To: linux-pci@vger.kernel.org Cc: Andrey Smirnov , yurovsky@gmail.com, Lucas Stach , Bjorn Helgaas , Fabio Estevam , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [RESEND PATCH v5 4/4] PCI: imx6: Allow probe deferal by reset GPIO Date: Mon, 20 Feb 2017 08:09:00 -0800 Message-Id: <20170220160900.7014-5-andrew.smirnov@gmail.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170220160900.7014-1-andrew.smirnov@gmail.com> References: <20170220160900.7014-1-andrew.smirnov@gmail.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Some designs implement reset GPIO via a GPIO expander connected to a peripheral bus. One such example would be i.MX7 Sabre board where said GPIO is provided by SPI shift register connected to a bitbanged SPI bus. In order to support such designs allow reset GPIO request to defer probing of the driver. Cc: yurovsky@gmail.com Cc: Lucas Stach Cc: Bjorn Helgaas Cc: Fabio Estevam Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Andrey Smirnov --- drivers/pci/host/pci-imx6.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index 071251f3..fe832e7f 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -638,8 +638,8 @@ static struct pcie_host_ops imx6_pcie_host_ops = { .host_init = imx6_pcie_host_init, }; -static int __init imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, - struct platform_device *pdev) +static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, + struct platform_device *pdev) { struct pcie_port *pp = &imx6_pcie->pp; struct device *dev = pp->dev; @@ -674,7 +674,7 @@ static int __init imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, return 0; } -static int __init imx6_pcie_probe(struct platform_device *pdev) +static int imx6_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct imx6_pcie *imx6_pcie; @@ -693,10 +693,6 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) imx6_pcie->variant = (enum imx6_pcie_variants)of_device_get_match_data(dev); - /* Added for PCI abort handling */ - hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, - "imprecise external abort"); - dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); pp->dbi_base = devm_ioremap_resource(dev, dbi_base); if (IS_ERR(pp->dbi_base)) @@ -716,6 +712,8 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) dev_err(dev, "unable to get reset gpio\n"); return ret; } + } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) { + return imx6_pcie->reset_gpio; } /* Fetch clocks */ @@ -828,11 +826,22 @@ static struct platform_driver imx6_pcie_driver = { .name = "imx6q-pcie", .of_match_table = imx6_pcie_of_match, }, + .probe = imx6_pcie_probe, .shutdown = imx6_pcie_shutdown, }; static int __init imx6_pcie_init(void) { - return platform_driver_probe(&imx6_pcie_driver, imx6_pcie_probe); + /* + * Since probe() can be deferred we need to make sure that + * hook_fault_code is not called after __init memory is freed + * by kernel and since imx6q_pcie_abort_handler() is a no-op + * we can install the handler here without risking it + * accessing some unitialized driver state + */ + hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, + "imprecise external abort"); + + return platform_driver_register(&imx6_pcie_driver); } device_initcall(imx6_pcie_init);