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]> --- .../devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++ drivers/pci/host/pci-imx6.c | 20 +++++++++++++++++++- 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt index 6fbba53..fe912bd 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: +- power-supply: A regulator that controls power to the port + Example: pcie@0x01000000 { diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index 69202d1..9c2140e 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 *power_reg; }; /* PCIe Root Complex registers (memory-mapped) */ @@ -588,6 +590,19 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) } } + /* Fetch power supply */ + imx6_pcie->power_reg = devm_regulator_get(&pdev->dev, "power"); + if (IS_ERR(imx6_pcie->power_reg)) + imx6_pcie->power_reg = 0; + + if (imx6_pcie->power_reg) { + ret = regulator_enable(imx6_pcie->power_reg); + if (ret) { + dev_err(&pdev->dev, "Unable to enable power regulator"); + return ret; + } + } + /* Fetch clocks */ imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy"); if (IS_ERR(imx6_pcie->pcie_phy)) { @@ -619,8 +634,11 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) } ret = imx6_add_pcie_port(pp, pdev); - if (ret < 0) + if (ret < 0) { + if (imx6_pcie->power_reg) + regulator_disable(imx6_pcie->power_reg); return ret; + } platform_set_drvdata(pdev, imx6_pcie); return 0; -- 2.1.3 -- 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
