PCI: imx6: Convert to use agnostic GPIO API

The of_gpio.h legacy API is going to be removed. In preparation for that,
convert the driver to the agnostic API.

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20240506142142.4042810-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Author: andy-shev

drivers/pci/controller/dwc/pci-imx6.c

@@ -11,14 +11,13 @@
 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/kernel.h>
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
 #include <linux/of_address.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
@@ -107,8 +106,7 @@ struct imx6_pcie_drvdata {
 
 struct imx6_pcie {
 	struct dw_pcie		*pci;
-	int			reset_gpio;
-	bool			gpio_active_high;
+	struct gpio_desc	*reset_gpiod;
 	bool			link_is_up;
 	struct clk_bulk_data	clks[IMX6_PCIE_MAX_CLKS];
 	struct regmap		*iomuxc_gpr;
@@ -721,9 +719,7 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 	}
 
 	/* Some boards don't have PCIe reset GPIO. */
-	if (gpio_is_valid(imx6_pcie->reset_gpio))
-		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
-					imx6_pcie->gpio_active_high);
+	gpiod_set_value_cansleep(imx6_pcie->reset_gpiod, 1);
 }
 
 static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
@@ -771,10 +767,9 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 	}
 
 	/* Some boards don't have PCIe reset GPIO. */
-	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+	if (imx6_pcie->reset_gpiod) {
 		msleep(100);
-		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
-					!imx6_pcie->gpio_active_high);
+		gpiod_set_value_cansleep(imx6_pcie->reset_gpiod, 0);
 		/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
 		msleep(100);
 	}
@@ -1285,22 +1280,11 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 		return PTR_ERR(pci->dbi_base);
 
 	/* Fetch GPIOs */
-	imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
-	imx6_pcie->gpio_active_high = of_property_read_bool(node,
-						"reset-gpio-active-high");
-	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
-		ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
-				imx6_pcie->gpio_active_high ?
-					GPIOF_OUT_INIT_HIGH :
-					GPIOF_OUT_INIT_LOW,
-				"PCIe reset");
-		if (ret) {
-			dev_err(dev, "unable to get reset gpio\n");
-			return ret;
-		}
-	} else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
-		return imx6_pcie->reset_gpio;
-	}
+	imx6_pcie->reset_gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(imx6_pcie->reset_gpiod))
+		return dev_err_probe(dev, PTR_ERR(imx6_pcie->reset_gpiod),
+				     "unable to get reset gpio\n");
+	gpiod_set_consumer_name(imx6_pcie->reset_gpiod, "PCIe reset");
 
 	if (imx6_pcie->drvdata->clks_cnt >= IMX6_PCIE_MAX_CLKS)
 		return dev_err_probe(dev, -ENOMEM, "clks_cnt is too big\n");