[PATCH V2] PCI: rcar: Use runtime PM to control controller clock

[Marek Vasut]

From: Dien Pham <dien.pham...@rvc.renesas.com>

The controller clock can be switched off during suspend/resume,
let runtime PM take care of that.

Signed-off-by: Dien Pham <dien.pham...@rvc.renesas.com>
Signed-off-by: Hien Dang <hien.dang...@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+rene...@gmail.com>
Cc: Geert Uytterhoeven <geert+rene...@glider.be>
Cc: Simon Horman <horms+rene...@verge.net.au>
Cc: Wolfram Sang <w...@the-dreams.de>
Cc: linux-renesas-soc@vger.kernel.org
To: linux-...@vger.kernel.org
---
V2: - Reorder the fail path in rcar_pcie_probe() to cater for the
      reordering of function calls in probe
    - Dispose of fail_clk in rcar_pcie_get_resources()
---
 drivers/pci/host/pcie-rcar.c | 37 ++++++++++++-------------------------
 1 file changed, 12 insertions(+), 25 deletions(-)

diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
index 12796eccb2be..1a7254ec16da 100644
--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c
@@ -145,7 +145,6 @@ struct rcar_pcie {
        void __iomem            *base;
        struct list_head        resources;
        int                     root_bus_nr;
-       struct clk              *clk;
        struct clk              *bus_clk;
        struct                  rcar_msi msi;
 };
@@ -917,24 +916,14 @@ static int rcar_pcie_get_resources(struct rcar_pcie *pcie)
        if (IS_ERR(pcie->base))
                return PTR_ERR(pcie->base);
 
-       pcie->clk = devm_clk_get(dev, "pcie");
-       if (IS_ERR(pcie->clk)) {
-               dev_err(dev, "cannot get platform clock\n");
-               return PTR_ERR(pcie->clk);
-       }
-       err = clk_prepare_enable(pcie->clk);
-       if (err)
-               return err;
-
        pcie->bus_clk = devm_clk_get(dev, "pcie_bus");
        if (IS_ERR(pcie->bus_clk)) {
                dev_err(dev, "cannot get pcie bus clock\n");
-               err = PTR_ERR(pcie->bus_clk);
-               goto fail_clk;
+               return PTR_ERR(pcie->bus_clk);
        }
        err = clk_prepare_enable(pcie->bus_clk);
        if (err)
-               goto fail_clk;
+               return err;
 
        i = irq_of_parse_and_map(dev->of_node, 0);
        if (!i) {
@@ -956,8 +945,6 @@ static int rcar_pcie_get_resources(struct rcar_pcie *pcie)
 
 err_map_reg:
        clk_disable_unprepare(pcie->bus_clk);
-fail_clk:
-       clk_disable_unprepare(pcie->clk);
 
        return err;
 }
@@ -1125,6 +1112,13 @@ static int rcar_pcie_probe(struct platform_device *pdev)
 
        rcar_pcie_parse_request_of_pci_ranges(pcie);
 
+       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;
+       }
+
        err = rcar_pcie_get_resources(pcie);
        if (err < 0) {
                dev_err(dev, "failed to request resources: %d\n", err);
@@ -1135,13 +1129,6 @@ static int rcar_pcie_probe(struct platform_device *pdev)
        if (err)
                goto err_free_bridge;
 
-       pm_runtime_enable(dev);
-       err = pm_runtime_get_sync(dev);
-       if (err < 0) {
-               dev_err(dev, "pm_runtime_get_sync failed\n");
-               goto err_pm_disable;
-       }
-
        /* Failure to get a link might just be that no cards are inserted */
        hw_init_fn = of_device_get_match_data(dev);
        err = hw_init_fn(pcie);
@@ -1173,13 +1160,13 @@ static int rcar_pcie_probe(struct platform_device *pdev)
 err_pm_put:
        pm_runtime_put(dev);
 
-err_pm_disable:
-       pm_runtime_disable(dev);
-
 err_free_bridge:
        pci_free_host_bridge(bridge);
        pci_free_resource_list(&pcie->resources);
 
+err_pm_disable:
+       pm_runtime_disable(dev);
+
        return err;
 }
 
-- 
2.11.0