PCI: imx6: Turn off regulator when system is in suspend mode

The driver should undo any enables it did itself. The regulator disable
shouldn't be basing decisions on regulator_is_enabled().

Move the regulator_disable to the suspend function, turn off regulator when
the system is in suspend mode.

Link: https://lore.kernel.org/r/1657783869-19194-11-git-send-email-hongxing.zhu@nxp.comSigned-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/controller/dwc/pci-imx6.c

@@ -670,8 +670,6 @@ static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
 
 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 {
-	struct device *dev = imx6_pcie->pci->dev;
-
 	switch (imx6_pcie->drvdata->variant) {
 	case IMX7D:
 	case IMX8MQ:
@@ -702,14 +700,6 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 		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);
-	}
-
 	/* Some boards don't have PCIe reset GPIO. */
 	if (gpio_is_valid(imx6_pcie->reset_gpio))
 		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
@@ -722,7 +712,7 @@ static int 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)) {
+	if (imx6_pcie->vpcie) {
 		ret = regulator_enable(imx6_pcie->vpcie);
 		if (ret) {
 			dev_err(dev, "failed to enable vpcie regulator: %d\n",
@@ -795,7 +785,7 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 	return 0;
 
 err_clks:
-	if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
+	if (imx6_pcie->vpcie) {
 		ret = regulator_disable(imx6_pcie->vpcie);
 		if (ret)
 			dev_err(dev, "failed to disable vpcie regulator: %d\n",
@@ -1021,6 +1011,9 @@ static int imx6_pcie_suspend_noirq(struct device *dev)
 		break;
 	}
 
+	if (imx6_pcie->vpcie)
+		regulator_disable(imx6_pcie->vpcie);
+
 	return 0;
 }