Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751761AbdFPQ6Z (ORCPT ); Fri, 16 Jun 2017 12:58:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:50166 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750903AbdFPQ6Y (ORCPT ); Fri, 16 Jun 2017 12:58:24 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5A04214E2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=helgaas@kernel.org Date: Fri, 16 Jun 2017 11:58:18 -0500 From: Bjorn Helgaas To: Quentin Schulz Cc: hongxing.zhu@nxp.com, l.stach@pengutronix.de, bhelgaas@google.com, robh+dt@kernel.org, mark.rutland@arm.com, thomas.petazzoni@free-electrons.com, devicetree@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] PCI: imx6: add regulator support Message-ID: <20170616165818.GC11129@bhelgaas-glaptop.roam.corp.google.com> References: <20170608080742.3910-1-quentin.schulz@free-electrons.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170608080742.3910-1-quentin.schulz@free-electrons.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4589 Lines: 125 On Thu, Jun 08, 2017 at 10:07:42AM +0200, Quentin Schulz wrote: > Some boards might require to control a regulator to power the PCIe port. > > This adds support for an optional regulator defined in Device Tree > linked in the PCIe controller under `vpcie-supply`. If present, the > regulator will be disabled and then enabled as part of the PCIe host > initialization process and will be disabled when shutting down. > > Signed-off-by: Quentin Schulz Applied with acks from Rob & Richard to pci/host-imx6 for v4.13, thanks! I converted the pr_err() in imx6_pcie_assert_core_reset() to a dev_err(). > --- > .../devicetree/bindings/pci/fsl,imx6q-pcie.txt | 4 +++ > drivers/pci/dwc/pci-imx6.c | 34 +++++++++++++++++++++- > 2 files changed, 37 insertions(+), 1 deletion(-) > > diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > index e3d5680875b1..cf92d3ba5a26 100644 > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > @@ -33,6 +33,10 @@ Optional properties: > - reset-gpio-active-high: If present then the reset sequence using the GPIO > specified in the "reset-gpio" property is reversed (H=reset state, > L=operation state). > +- vpcie-supply: Should specify the regulator in charge of PCIe port power. > + The regulator will be enabled when initializing the PCIe host and > + disabled either as part of the init process or when shutting down the > + host. > > Additional required properties for imx6sx-pcie: > - clock names: Must include the following additional entries: > diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c > index 19a289b8cc94..f9b7500c9aff 100644 > --- a/drivers/pci/dwc/pci-imx6.c > +++ b/drivers/pci/dwc/pci-imx6.c > @@ -24,6 +24,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -59,6 +60,7 @@ struct imx6_pcie { > u32 tx_swing_full; > u32 tx_swing_low; > int link_gen; > + struct regulator *vpcie; > }; > > /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */ > @@ -310,6 +312,13 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) > IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16); > break; > } > + > + if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { > + int ret = regulator_disable(imx6_pcie->vpcie); > + > + if (ret) > + pr_err("failed to disable vpcie regulator: %d\n", ret); > + } > } > > static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie) > @@ -376,10 +385,19 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) > struct device *dev = pci->dev; > int ret; > > + if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) { > + ret = regulator_enable(imx6_pcie->vpcie); > + if (ret) { > + dev_err(dev, "failed to enable vpcie regulator: %d\n", > + ret); > + return; > + } > + } > + > ret = clk_prepare_enable(imx6_pcie->pcie_phy); > if (ret) { > dev_err(dev, "unable to enable pcie_phy clock\n"); > - return; > + goto err_pcie_phy; > } > > ret = clk_prepare_enable(imx6_pcie->pcie_bus); > @@ -439,6 +457,13 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) > clk_disable_unprepare(imx6_pcie->pcie_bus); > err_pcie_bus: > clk_disable_unprepare(imx6_pcie->pcie_phy); > +err_pcie_phy: > + if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { > + ret = regulator_disable(imx6_pcie->vpcie); > + if (ret) > + dev_err(dev, "failed to disable vpcie regulator: %d\n", > + ret); > + } > } > > static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie) > @@ -802,6 +827,13 @@ static int imx6_pcie_probe(struct platform_device *pdev) > if (ret) > imx6_pcie->link_gen = 1; > > + imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie"); > + if (IS_ERR(imx6_pcie->vpcie)) { > + if (PTR_ERR(imx6_pcie->vpcie) == -EPROBE_DEFER) > + return -EPROBE_DEFER; > + imx6_pcie->vpcie = NULL; > + } > + > platform_set_drvdata(pdev, imx6_pcie); > > ret = imx6_add_pcie_port(imx6_pcie, pdev); > -- > 2.11.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel