[PATCH v2] PCI: imx6: Enable the vpcie regulator when fetch it

[Richard Zhu <hongxing.zhu@xxxxxxx>]

Enable the vpcie regulator at probe time and keep it enabled for the
entire PCIe controller lifecycle. This ensures support for outbound
wake-up mechanism such as WAKE# signaling.

Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
---
 drivers/pci/controller/dwc/pci-imx6.c | 27 ++++-----------------------
 1 file changed, 4 insertions(+), 23 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 5a38cfaf989b..7cab4bcfae56 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -159,7 +159,6 @@ struct imx_pcie {
 	u32			tx_deemph_gen2_6db;
 	u32			tx_swing_full;
 	u32			tx_swing_low;
-	struct regulator	*vpcie;
 	struct regulator	*vph;
 	void __iomem		*phy_base;
 
@@ -1198,15 +1197,6 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp)
 	struct imx_pcie *imx_pcie = to_imx_pcie(pci);
 	int ret;
 
-	if (imx_pcie->vpcie) {
-		ret = regulator_enable(imx_pcie->vpcie);
-		if (ret) {
-			dev_err(dev, "failed to enable vpcie regulator: %d\n",
-				ret);
-			return ret;
-		}
-	}
-
 	if (pp->bridge && imx_check_flag(imx_pcie, IMX_PCIE_FLAG_HAS_LUT)) {
 		pp->bridge->enable_device = imx_pcie_enable_device;
 		pp->bridge->disable_device = imx_pcie_disable_device;
@@ -1222,7 +1212,7 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp)
 	ret = imx_pcie_clk_enable(imx_pcie);
 	if (ret) {
 		dev_err(dev, "unable to enable pcie clocks: %d\n", ret);
-		goto err_reg_disable;
+		return ret;
 	}
 
 	if (imx_pcie->phy) {
@@ -1269,9 +1259,6 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp)
 	phy_exit(imx_pcie->phy);
 err_clk_disable:
 	imx_pcie_clk_disable(imx_pcie);
-err_reg_disable:
-	if (imx_pcie->vpcie)
-		regulator_disable(imx_pcie->vpcie);
 	return ret;
 }
 
@@ -1286,9 +1273,6 @@ static void imx_pcie_host_exit(struct dw_pcie_rp *pp)
 		phy_exit(imx_pcie->phy);
 	}
 	imx_pcie_clk_disable(imx_pcie);
-
-	if (imx_pcie->vpcie)
-		regulator_disable(imx_pcie->vpcie);
 }
 
 static void imx_pcie_host_post_init(struct dw_pcie_rp *pp)
@@ -1739,12 +1723,9 @@ static int imx_pcie_probe(struct platform_device *pdev)
 	pci->max_link_speed = 1;
 	of_property_read_u32(node, "fsl,max-link-speed", &pci->max_link_speed);
 
-	imx_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
-	if (IS_ERR(imx_pcie->vpcie)) {
-		if (PTR_ERR(imx_pcie->vpcie) != -ENODEV)
-			return PTR_ERR(imx_pcie->vpcie);
-		imx_pcie->vpcie = NULL;
-	}
+	ret = devm_regulator_get_enable_optional(&pdev->dev, "vpcie");
+	if (ret < 0 && ret != -ENODEV)
+		return dev_err_probe(dev, ret, "failed to enable vpcie");
 
 	imx_pcie->vph = devm_regulator_get_optional(&pdev->dev, "vph");
 	if (IS_ERR(imx_pcie->vph)) {
-- 
2.37.1