From patchwork Fri Dec 4 20:59:06 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Bjorn Helgaas X-Patchwork-Id: 552886 Return-Path: X-Original-To: incoming-imx@patchwork.ozlabs.org Delivered-To: patchwork-incoming-imx@bilbo.ozlabs.org Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2001:1868:205::9]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 273D11402A0 for ; Sat, 5 Dec 2015 08:01:54 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a4xS5-0000dB-DG; Fri, 04 Dec 2015 20:59:37 +0000 Received: from mail.kernel.org ([198.145.29.136]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a4xS2-0000bn-Ib for linux-arm-kernel@lists.infradead.org; Fri, 04 Dec 2015 20:59:35 +0000 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EED8620613; Fri, 4 Dec 2015 20:59:12 +0000 (UTC) Received: from localhost (unknown [69.71.1.1]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A466E20610; Fri, 4 Dec 2015 20:59:11 +0000 (UTC) Date: Fri, 4 Dec 2015 14:59:06 -0600 From: Bjorn Helgaas To: Petr =?utf-8?Q?=C5=A0tetiar?= Subject: Re: [PATCH v3] PCI: imx6: Fix reset-gpio to work with active low GPIO Message-ID: <20151204205906.GG20125@localhost> References: <1448620464.3689.94.camel@pengutronix.de> <1448621794-19916-1-git-send-email-ynezz@true.cz> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1448621794-19916-1-git-send-email-ynezz@true.cz> User-Agent: Mutt/1.5.21 (2010-09-15) X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151204_125934_670749_2599BC56 X-CRM114-Status: GOOD ( 18.74 ) X-Spam-Score: -4.2 (----) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-4.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [198.145.29.136 listed in list.dnswl.org] -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, Richard Zhu , linux-arm-kernel@lists.infradead.org, Lucas Stach Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+incoming-imx=patchwork.ozlabs.org@lists.infradead.org List-Id: linux-imx-kernel.lists.patchwork.ozlabs.org On Fri, Nov 27, 2015 at 11:56:34AM +0100, Petr Štetiar wrote: > It's currently not possible to use reset-gpio on board where the GPIO is > active low as the code incorrectly assumes, that reset-gpio will be > always active high. > > In my case the broken behavior was observed on Toradex Apalis SoM with > Ixora base board. > > Signed-off-by: Petr Štetiar Applied as follows with Lucas' reviewed-by to pci/host-imx6 for v4.5, thanks! commit 5c5fb40de8f14391a1238db05cef88754faf9229 Author: Petr Štetiar Date: Fri Nov 27 11:56:34 2015 +0100 PCI: imx6: Add support for active-low reset GPIO We previously used of_get_named_gpio(), which ignores the OF flags cell, so the reset GPIO defaulted to "active high." This doesn't work on the Toradex Apalis SoM with Ixora base board, which has an active-low reset GPIO. Use devm_gpiod_get_optional() instead so we pay attention to the active high/low flag. This also adds support for GPIOs described via ACPI. [bhelgaas: changelog] Signed-off-by: Petr Štetiar Signed-off-by: Bjorn Helgaas Reviewed-by: Lucas Stach diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index 3c3b37f..8e9afa5 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -32,7 +32,7 @@ #define to_imx6_pcie(x) container_of(x, struct imx6_pcie, pp) struct imx6_pcie { - int reset_gpio; + struct gpio_desc *reset_gpio; struct clk *pcie_bus; struct clk *pcie_phy; struct clk *pcie; @@ -287,10 +287,10 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp) usleep_range(200, 500); /* Some boards don't have PCIe reset GPIO. */ - if (gpio_is_valid(imx6_pcie->reset_gpio)) { - gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0); + if (imx6_pcie->reset_gpio) { + gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 0); msleep(100); - gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1); + gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1); } return 0; @@ -560,7 +560,6 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) { struct imx6_pcie *imx6_pcie; struct pcie_port *pp; - struct device_node *np = pdev->dev.of_node; struct resource *dbi_base; int ret; @@ -581,15 +580,8 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) return PTR_ERR(pp->dbi_base); /* Fetch GPIOs */ - imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0); - if (gpio_is_valid(imx6_pcie->reset_gpio)) { - ret = devm_gpio_request_one(&pdev->dev, imx6_pcie->reset_gpio, - GPIOF_OUT_INIT_LOW, "PCIe reset"); - if (ret) { - dev_err(&pdev->dev, "unable to get reset gpio\n"); - return ret; - } - } + imx6_pcie->reset_gpio = devm_gpiod_get_optional(&pdev->dev, "reset", + GPIOD_OUT_LOW); /* Fetch clocks */ imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy");