[PATCH] PCI: kirin: Return -EPROBE_DEFER in case the gpio isn't ready

[Bean Huo]

From: Bean Huo <bean...@micron.com>

PCI driver might be probed before the gpiochip, so, of_get_named_gpio()
can return -EPROBE_DEFER. And let kirin_pcie_probe() directly return
-ENODEV, which will result in the PCIe probe failure and the PCIe
will not be probed again after the gpiochip driver is loaded.

Fix the above issue by letting kirin_pcie_probe() return -EPROBE_DEFER in
such a case.

Fixes: 6e0832fa432e ("PCI: Collect all native drivers under 
drivers/pci/controller")
Signed-off-by: Bean Huo <bean...@micron.com>
---
 drivers/pci/controller/dwc/pcie-kirin.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-kirin.c 
b/drivers/pci/controller/dwc/pcie-kirin.c
index e496f51e0152..74b88d158072 100644
--- a/drivers/pci/controller/dwc/pcie-kirin.c
+++ b/drivers/pci/controller/dwc/pcie-kirin.c
@@ -507,8 +507,12 @@ static int kirin_pcie_probe(struct platform_device *pdev)
 
        kirin_pcie->gpio_id_reset = of_get_named_gpio(dev->of_node,
                                                      "reset-gpios", 0);
-       if (kirin_pcie->gpio_id_reset < 0)
+       if (kirin_pcie->gpio_id_reset == -EPROBE_DEFER) {
+               return -EPROBE_DEFER;
+       } else if (!gpio_is_valid(kirin_pcie->gpio_id_reset)) {
+               dev_err(dev, "unable to get a valid gpio pin\n");
                return -ENODEV;
+       }
 
        ret = kirin_pcie_power_on(kirin_pcie);
        if (ret)
-- 
2.17.1