gpio: mt7621: use new generic GPIO chip API

Convert the driver to using the new generic GPIO chip interfaces from
linux/gpio/generic.h.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250910-gpio-mmio-gpio-conv-part4-v2-8-f3d1a4c57124@linaro.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Author: Bartosz Golaszewski

drivers/gpio/gpio-mt7621.c

@@ -6,6 +6,7 @@
 
 #include <linux/err.h>
 #include <linux/gpio/driver.h>
+#include <linux/gpio/generic.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/module.h>
@@ -30,7 +31,7 @@
 
 struct mtk_gc {
 	struct irq_chip irq_chip;
-	struct gpio_chip chip;
+	struct gpio_generic_chip chip;
 	spinlock_t lock;
 	int bank;
 	u32 rising;
@@ -59,27 +60,29 @@ struct mtk {
 static inline struct mtk_gc *
 to_mediatek_gpio(struct gpio_chip *chip)
 {
-	return container_of(chip, struct mtk_gc, chip);
+	struct gpio_generic_chip *gen_gc = to_gpio_generic_chip(chip);
+
+	return container_of(gen_gc, struct mtk_gc, chip);
 }
 
 static inline void
 mtk_gpio_w32(struct mtk_gc *rg, u32 offset, u32 val)
 {
-	struct gpio_chip *gc = &rg->chip;
+	struct gpio_chip *gc = &rg->chip.gc;
 	struct mtk *mtk = gpiochip_get_data(gc);
 
 	offset = (rg->bank * GPIO_BANK_STRIDE) + offset;
-	gc->write_reg(mtk->base + offset, val);
+	gpio_generic_write_reg(&rg->chip, mtk->base + offset, val);
 }
 
 static inline u32
 mtk_gpio_r32(struct mtk_gc *rg, u32 offset)
 {
-	struct gpio_chip *gc = &rg->chip;
+	struct gpio_chip *gc = &rg->chip.gc;
 	struct mtk *mtk = gpiochip_get_data(gc);
 
 	offset = (rg->bank * GPIO_BANK_STRIDE) + offset;
-	return gc->read_reg(mtk->base + offset);
+	return gpio_generic_read_reg(&rg->chip, mtk->base + offset);
 }
 
 static irqreturn_t
@@ -220,6 +223,7 @@ static const struct irq_chip mt7621_irq_chip = {
 static int
 mediatek_gpio_bank_probe(struct device *dev, int bank)
 {
+	struct gpio_generic_chip_config config;
 	struct mtk *mtk = dev_get_drvdata(dev);
 	struct mtk_gc *rg;
 	void __iomem *dat, *set, *ctrl, *diro;
@@ -236,21 +240,30 @@ mediatek_gpio_bank_probe(struct device *dev, int bank)
 	ctrl = mtk->base + GPIO_REG_DCLR + (rg->bank * GPIO_BANK_STRIDE);
 	diro = mtk->base + GPIO_REG_CTRL + (rg->bank * GPIO_BANK_STRIDE);
 
-	ret = bgpio_init(&rg->chip, dev, 4, dat, set, ctrl, diro, NULL,
-			 BGPIOF_NO_SET_ON_INPUT);
+	config = (struct gpio_generic_chip_config) {
+		.dev = dev,
+		.sz = 4,
+		.dat = dat,
+		.set = set,
+		.clr = ctrl,
+		.dirout = diro,
+		.flags = BGPIOF_NO_SET_ON_INPUT,
+	};
+
+	ret = gpio_generic_chip_init(&rg->chip, &config);
 	if (ret) {
-		dev_err(dev, "bgpio_init() failed\n");
+		dev_err(dev, "failed to initialize generic GPIO chip\n");
 		return ret;
 	}
 
-	rg->chip.of_gpio_n_cells = 2;
-	rg->chip.of_xlate = mediatek_gpio_xlate;
-	rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d",
+	rg->chip.gc.of_gpio_n_cells = 2;
+	rg->chip.gc.of_xlate = mediatek_gpio_xlate;
+	rg->chip.gc.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d",
 					dev_name(dev), bank);
-	if (!rg->chip.label)
+	if (!rg->chip.gc.label)
 		return -ENOMEM;
 
-	rg->chip.offset = bank * MTK_BANK_WIDTH;
+	rg->chip.gc.offset = bank * MTK_BANK_WIDTH;
 
 	if (mtk->gpio_irq) {
 		struct gpio_irq_chip *girq;
@@ -261,15 +274,15 @@ mediatek_gpio_bank_probe(struct device *dev, int bank)
 		 */
 		ret = devm_request_irq(dev, mtk->gpio_irq,
 				       mediatek_gpio_irq_handler, IRQF_SHARED,
-				       rg->chip.label, &rg->chip);
+				       rg->chip.gc.label, &rg->chip.gc);
 
 		if (ret) {
 			dev_err(dev, "Error requesting IRQ %d: %d\n",
 				mtk->gpio_irq, ret);
 			return ret;
 		}
 
-		girq = &rg->chip.irq;
+		girq = &rg->chip.gc.irq;
 		gpio_irq_chip_set_chip(girq, &mt7621_irq_chip);
 		/* This will let us handle the parent IRQ in the driver */
 		girq->parent_handler = NULL;
@@ -279,17 +292,17 @@ mediatek_gpio_bank_probe(struct device *dev, int bank)
 		girq->handler = handle_simple_irq;
 	}
 
-	ret = devm_gpiochip_add_data(dev, &rg->chip, mtk);
+	ret = devm_gpiochip_add_data(dev, &rg->chip.gc, mtk);
 	if (ret < 0) {
 		dev_err(dev, "Could not register gpio %d, ret=%d\n",
-			rg->chip.ngpio, ret);
+			rg->chip.gc.ngpio, ret);
 		return ret;
 	}
 
 	/* set polarity to low for all gpios */
 	mtk_gpio_w32(rg, GPIO_REG_POL, 0);
 
-	dev_info(dev, "registering %d gpios\n", rg->chip.ngpio);
+	dev_info(dev, "registering %d gpios\n", rg->chip.gc.ngpio);
 
 	return 0;
 }