gpio: ath79: remove support for platform data

There are no more board files defining platform data for this driver so
remove the header and support from the driver.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240821121456.19553-4-brgl@bgdev.plSigned-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-ath79.c

@@ -14,7 +14,6 @@
 #include <linux/irq.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
-#include <linux/platform_data/gpio-ath79.h>
 #include <linux/platform_device.h>
 
 #define AR71XX_GPIO_REG_OE		0x00
@@ -225,9 +224,7 @@ MODULE_DEVICE_TABLE(of, ath79_gpio_of_match);
 
 static int ath79_gpio_probe(struct platform_device *pdev)
 {
-	struct ath79_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct device *dev = &pdev->dev;
-	struct device_node *np = dev->of_node;
 	struct ath79_gpio_ctrl *ctrl;
 	struct gpio_irq_chip *girq;
 	u32 ath79_gpio_count;
@@ -238,21 +235,14 @@ static int ath79_gpio_probe(struct platform_device *pdev)
 	if (!ctrl)
 		return -ENOMEM;
 
-	if (np) {
-		err = device_property_read_u32(dev, "ngpios", &ath79_gpio_count);
-		if (err) {
-			dev_err(dev, "ngpios property is not valid\n");
-			return err;
-		}
-		oe_inverted = device_is_compatible(dev, "qca,ar9340-gpio");
-	} else if (pdata) {
-		ath79_gpio_count = pdata->ngpios;
-		oe_inverted = pdata->oe_inverted;
-	} else {
-		dev_err(dev, "No DT node or platform data found\n");
-		return -EINVAL;
+	err = device_property_read_u32(dev, "ngpios", &ath79_gpio_count);
+	if (err) {
+		dev_err(dev, "ngpios property is not valid\n");
+		return err;
 	}
 
+	oe_inverted = device_is_compatible(dev, "qca,ar9340-gpio");
+
 	if (ath79_gpio_count >= 32) {
 		dev_err(dev, "ngpios must be less than 32\n");
 		return -EINVAL;

include/linux/platform_data/gpio-ath79.h

-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- *  Atheros AR7XXX/AR9XXX GPIO controller platform data
- *
- * Copyright (C) 2015 Alban Bedel <albeu@free.fr>
- */
-
-#ifndef __LINUX_PLATFORM_DATA_GPIO_ATH79_H
-#define __LINUX_PLATFORM_DATA_GPIO_ATH79_H
-
-struct ath79_gpio_platform_data {
-	unsigned ngpios;
-	bool oe_inverted;
-};
-
-#endif