PCI: rcar: Add runtime PM support to pcie-rcar

If runtime PM is enabled in the kernel config, simply enable the clocks
once during probe.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
index c72c0ae31feb644a3273a72b74a75673edf4e0cb..f157b50ee42b9bbf44735915fadb0eed08c5613b 100644 (file)
--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c
@@ -26,6 +26,7 @@
 #include <linux/of_platform.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 
 #define DRV_NAME "rcar-pcie"
@@ -994,32 +995,51 @@ static int rcar_pcie_probe(struct platform_device *pdev)
         if (err)
                return err;
 
-       if (IS_ENABLED(CONFIG_PCI_MSI)) {
-               err = rcar_pcie_enable_msi(pcie);
-               if (err < 0) {
-                       dev_err(&pdev->dev,
-                               "failed to enable MSI support: %d\n",
-                               err);
-                       return err;
-               }
-       }
-
        of_id = of_match_device(rcar_pcie_of_match, pcie->dev);
        if (!of_id || !of_id->data)
                return -EINVAL;
        hw_init_fn = of_id->data;
 
+       pm_runtime_enable(pcie->dev);
+       err = pm_runtime_get_sync(pcie->dev);
+       if (err < 0) {
+               dev_err(pcie->dev, "pm_runtime_get_sync failed\n");
+               goto err_pm_disable;
+       }
+
        /* Failure to get a link might just be that no cards are inserted */
        err = hw_init_fn(pcie);
        if (err) {
                dev_info(&pdev->dev, "PCIe link down\n");
-               return 0;
+               err = 0;
+               goto err_pm_put;
        }
 
        data = rcar_pci_read_reg(pcie, MACSR);
        dev_info(&pdev->dev, "PCIe x%d: link up\n", (data >> 20) & 0x3f);
 
-       return rcar_pcie_enable(pcie);
+       if (IS_ENABLED(CONFIG_PCI_MSI)) {
+               err = rcar_pcie_enable_msi(pcie);
+               if (err < 0) {
+                       dev_err(&pdev->dev,
+                               "failed to enable MSI support: %d\n",
+                               err);
+                       goto err_pm_put;
+               }
+       }
+
+       err = rcar_pcie_enable(pcie);
+       if (err)
+               goto err_pm_put;
+
+       return 0;
+
+err_pm_put:
+       pm_runtime_put(pcie->dev);
+
+err_pm_disable:
+       pm_runtime_disable(pcie->dev);
+       return err;
 }
 
 static struct platform_driver rcar_pcie_driver = {