Am Montag, den 22.12.2014, 16:32 +0800 schrieb Sean Cross: > Some PCIe ports gate power to the slot. In order to prevent system lockup, > these boards must enable power to the slot before attempting communication > over the PCI bus. > > Signed-off-by: Sean Cross <[email protected]>
Reviewed-by: Lucas Stach <[email protected]> > --- > .../devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++ > drivers/pci/host/pci-imx6.c | 27 > ++++++++++++++++++++++ > 2 files changed, 30 insertions(+) > > diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > index 6fbba53..a806b68 100644 > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt > @@ -13,6 +13,9 @@ Required properties: > - clock-names: Must include the following additional entries: > - "pcie_phy" > > +Optional properties: > +- bus-supply: A regulator that controls power to the entire bus > + > Example: > > pcie@0x01000000 { > diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c > index 69202d1..8e4f957 100644 > --- a/drivers/pci/host/pci-imx6.c > +++ b/drivers/pci/host/pci-imx6.c > @@ -22,6 +22,7 @@ > #include <linux/pci.h> > #include <linux/platform_device.h> > #include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > #include <linux/resource.h> > #include <linux/signal.h> > #include <linux/types.h> > @@ -39,6 +40,7 @@ struct imx6_pcie { > struct pcie_port pp; > struct regmap *iomuxc_gpr; > void __iomem *mem_base; > + struct regulator *bus_supply; > }; > > /* PCIe Root Complex registers (memory-mapped) */ > @@ -523,6 +525,7 @@ static struct pcie_host_ops imx6_pcie_host_ops = { > static int __init imx6_add_pcie_port(struct pcie_port *pp, > struct platform_device *pdev) > { > + struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp); > int ret; > > if (IS_ENABLED(CONFIG_PCI_MSI)) { > @@ -544,9 +547,22 @@ static int __init imx6_add_pcie_port(struct pcie_port > *pp, > pp->root_bus_nr = -1; > pp->ops = &imx6_pcie_host_ops; > > + if (imx6_pcie->bus_supply) { > + ret = regulator_enable(imx6_pcie->bus_supply); > + if (ret) { > + dev_err(pp->dev, > + "unable to enable bus supply: %d\n", ret); > + return ret; > + } > + } > + > ret = dw_pcie_host_init(pp); > if (ret) { > dev_err(&pdev->dev, "failed to initialize host\n"); > + > + if (imx6_pcie->bus_supply) > + regulator_disable(imx6_pcie->bus_supply); > + > return ret; > } > > @@ -588,6 +604,17 @@ static int __init imx6_pcie_probe(struct platform_device > *pdev) > } > } > > + /* Fetch bus supply */ > + imx6_pcie->bus_supply = devm_regulator_get_optional(&pdev->dev, "bus"); > + if (IS_ERR(imx6_pcie->bus_supply)) { > + ret = PTR_ERR(imx6_pcie->bus_supply); > + if (ret == -EPROBE_DEFER) > + return ret; > + > + dev_err(&pdev->dev, "unable to get bus-supply\n"); > + return ret; > + } > + > /* Fetch clocks */ > imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy"); > if (IS_ERR(imx6_pcie->pcie_phy)) { -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
