PCI: dra7xx: Add PM support

Add PM support to pci-dra7xx so PCI clocks can be disabled during suspend
and enabled during resume without affecting PCI functionality.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJingoo Han <jingoohan1@gmail.com>

drivers/pci/host/pci-dra7xx.c

@@ -433,6 +433,56 @@ static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int dra7xx_pcie_suspend_noirq(struct device *dev)
+{
+	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
+	int count = dra7xx->phy_count;
+
+	while (count--) {
+		phy_power_off(dra7xx->phy[count]);
+		phy_exit(dra7xx->phy[count]);
+	}
+
+	return 0;
+}
+
+static int dra7xx_pcie_resume_noirq(struct device *dev)
+{
+	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
+	int phy_count = dra7xx->phy_count;
+	int ret;
+	int i;
+
+	for (i = 0; i < phy_count; i++) {
+		ret = phy_init(dra7xx->phy[i]);
+		if (ret < 0)
+			goto err_phy;
+
+		ret = phy_power_on(dra7xx->phy[i]);
+		if (ret < 0) {
+			phy_exit(dra7xx->phy[i]);
+			goto err_phy;
+		}
+	}
+
+	return 0;
+
+err_phy:
+	while (--i >= 0) {
+		phy_power_off(dra7xx->phy[i]);
+		phy_exit(dra7xx->phy[i]);
+	}
+
+	return ret;
+}
+#endif
+
+static const struct dev_pm_ops dra7xx_pcie_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend_noirq,
+				      dra7xx_pcie_resume_noirq)
+};
+
 static const struct of_device_id of_dra7xx_pcie_match[] = {
 	{ .compatible = "ti,dra7-pcie", },
 	{},
@@ -444,6 +494,7 @@ static struct platform_driver dra7xx_pcie_driver = {
 	.driver = {
 		.name	= "dra7-pcie",
 		.of_match_table = of_dra7xx_pcie_match,
+		.pm	= &dra7xx_pcie_pm_ops,
 	},
 };