PCI: imx6: Add support for active-low reset GPIO

We previously used of_get_named_gpio(), which ignores the OF flags cell, so
the reset GPIO defaulted to "active high." This doesn't work on the Toradex
Apalis SoM with Ixora base board, which has an active-low reset GPIO.

Use devm_gpiod_get_optional() instead so we pay attention to the active
high/low flag.  This also adds support for GPIOs described via ACPI.

[bhelgaas: changelog]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>

diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index 3c3b37f9a76ecf1718fe5f5eba4a064d70ef04f5..8e9afa5bd7deb50ce610951682ea3742bb6a029d 100644 (file)
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -32,7 +32,7 @@
 #define to_imx6_pcie(x)        container_of(x, struct imx6_pcie, pp)
 
 struct imx6_pcie {
-       int                     reset_gpio;
+       struct gpio_desc        *reset_gpio;
        struct clk              *pcie_bus;
        struct clk              *pcie_phy;
        struct clk              *pcie;
@@ -287,10 +287,10 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
        usleep_range(200, 500);
 
        /* Some boards don't have PCIe reset GPIO. */
-       if (gpio_is_valid(imx6_pcie->reset_gpio)) {
-               gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0);
+       if (imx6_pcie->reset_gpio) {
+               gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 0);
                msleep(100);
-               gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1);
+               gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1);
        }
        return 0;
 
@@ -560,7 +560,6 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
 {
        struct imx6_pcie *imx6_pcie;
        struct pcie_port *pp;
-       struct device_node *np = pdev->dev.of_node;
        struct resource *dbi_base;
        int ret;
 
@@ -581,15 +580,8 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
                return PTR_ERR(pp->dbi_base);
 
        /* Fetch GPIOs */
-       imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
-       if (gpio_is_valid(imx6_pcie->reset_gpio)) {
-               ret = devm_gpio_request_one(&pdev->dev, imx6_pcie->reset_gpio,
-                                           GPIOF_OUT_INIT_LOW, "PCIe reset");
-               if (ret) {
-                       dev_err(&pdev->dev, "unable to get reset gpio\n");
-                       return ret;
-               }
-       }
+       imx6_pcie->reset_gpio = devm_gpiod_get_optional(&pdev->dev, "reset",
+                                                       GPIOD_OUT_LOW);
 
        /* Fetch clocks */
        imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy");