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author | Quentin Schulz <quentin.schulz@free-electrons.com> | 2017-06-08 10:07:42 +0200 |
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committer | Bjorn Helgaas <bhelgaas@google.com> | 2017-07-02 18:43:39 -0500 |
commit | c26ebe98a103479dae9284fe0a86a95af4a5cd46 (patch) | |
tree | 5af5b1c5aa475d9d3c7f35e86c210c4940bc5f18 /drivers/pci | |
parent | 769b461fc0c0451bacf75826d5830fc07c5a57e4 (diff) | |
download | linux-c26ebe98a103479dae9284fe0a86a95af4a5cd46.tar.gz linux-c26ebe98a103479dae9284fe0a86a95af4a5cd46.tar.bz2 linux-c26ebe98a103479dae9284fe0a86a95af4a5cd46.zip |
PCI: imx6: Add regulator support
Some boards might require to control a regulator to power the PCIe port.
Add 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 <quentin.schulz@free-electrons.com>
[bhelgaas: use dev_err() instead of pr_err() in
imx6_pcie_assert_core_reset()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Richard Zhu <hongxing.zhu@nxp.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/dwc/pci-imx6.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c index a98cba55c7f0..9717ef71e71b 100644 --- a/drivers/pci/dwc/pci-imx6.c +++ b/drivers/pci/dwc/pci-imx6.c @@ -24,6 +24,7 @@ #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> @@ -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 */ @@ -257,6 +259,8 @@ static int imx6q_pcie_abort_handler(unsigned long addr, static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) { + struct device *dev = imx6_pcie->pci->dev; + switch (imx6_pcie->variant) { case IMX7D: reset_control_assert(imx6_pcie->pciephy_reset); @@ -283,6 +287,14 @@ 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) + dev_err(dev, "failed to disable vpcie regulator: %d\n", + ret); + } } static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie) @@ -349,10 +361,19 @@ 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); @@ -412,6 +433,13 @@ err_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) @@ -775,6 +803,13 @@ 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); |