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diff --git a/arch/arm/mach-s3c/gpio-core.h b/arch/arm/mach-s3c/gpio-core.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2008 Simtec Electronics
+ * http://armlinux.simtec.co.uk/
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C Platform - GPIO core
+ */
+
+#ifndef __PLAT_SAMSUNG_GPIO_CORE_H
+#define __PLAT_SAMSUNG_GPIO_CORE_H
+
+/* Bring in machine-local definitions, especially S3C_GPIO_END */
+#include "gpio-samsung.h"
+#include <linux/gpio/driver.h>
+
+#define GPIOCON_OFF (0x00)
+#define GPIODAT_OFF (0x04)
+
+#define con_4bit_shift(__off) ((__off) * 4)
+
+/* Define the core gpiolib support functions that the s3c platforms may
+ * need to extend or change depending on the hardware and the s3c chip
+ * selected at build or found at run time.
+ *
+ * These definitions are not intended for driver inclusion, there is
+ * nothing here that should not live outside the platform and core
+ * specific code.
+*/
+
+struct samsung_gpio_chip;
+
+/**
+ * struct samsung_gpio_pm - power management (suspend/resume) information
+ * @save: Routine to save the state of the GPIO block
+ * @resume: Routine to resume the GPIO block.
+ */
+struct samsung_gpio_pm {
+ void (*save)(struct samsung_gpio_chip *chip);
+ void (*resume)(struct samsung_gpio_chip *chip);
+};
+
+struct samsung_gpio_cfg;
+
+/**
+ * struct samsung_gpio_chip - wrapper for specific implementation of gpio
+ * @chip: The chip structure to be exported via gpiolib.
+ * @base: The base pointer to the gpio configuration registers.
+ * @group: The group register number for gpio interrupt support.
+ * @irq_base: The base irq number.
+ * @config: special function and pull-resistor control information.
+ * @lock: Lock for exclusive access to this gpio bank.
+ * @pm_save: Save information for suspend/resume support.
+ * @bitmap_gpio_int: Bitmap for representing GPIO interrupt or not.
+ *
+ * This wrapper provides the necessary information for the Samsung
+ * specific gpios being registered with gpiolib.
+ *
+ * The lock protects each gpio bank from multiple access of the shared
+ * configuration registers, or from reading of data whilst another thread
+ * is writing to the register set.
+ *
+ * Each chip has its own lock to avoid any contention between different
+ * CPU cores trying to get one lock for different GPIO banks, where each
+ * bank of GPIO has its own register space and configuration registers.
+ */
+struct samsung_gpio_chip {
+ struct gpio_chip chip;
+ struct samsung_gpio_cfg *config;
+ struct samsung_gpio_pm *pm;
+ void __iomem *base;
+ int irq_base;
+ int group;
+ spinlock_t lock;
+#ifdef CONFIG_PM
+ u32 pm_save[4];
+#endif
+ u32 bitmap_gpio_int;
+};
+
+static inline struct samsung_gpio_chip *to_samsung_gpio(struct gpio_chip *gpc)
+{
+ return container_of(gpc, struct samsung_gpio_chip, chip);
+}
+
+/**
+ * samsung_gpiolib_to_irq - convert gpio pin to irq number
+ * @chip: The gpio chip that the pin belongs to.
+ * @offset: The offset of the pin in the chip.
+ *
+ * This helper returns the irq number calculated from the chip->irq_base and
+ * the provided offset.
+ */
+extern int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset);
+
+/* exported for core SoC support to change */
+extern struct samsung_gpio_cfg s3c24xx_gpiocfg_default;
+
+#ifdef CONFIG_S3C_GPIO_TRACK
+extern struct samsung_gpio_chip *s3c_gpios[S3C_GPIO_END];
+
+static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int chip)
+{
+ return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL;
+}
+#else
+/* machine specific code should provide samsung_gpiolib_getchip */
+
+extern struct samsung_gpio_chip s3c24xx_gpios[];
+
+static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int pin)
+{
+ struct samsung_gpio_chip *chip;
+
+ if (pin > S3C_GPIO_END)
+ return NULL;
+
+ chip = &s3c24xx_gpios[pin/32];
+ return ((pin - chip->chip.base) < chip->chip.ngpio) ? chip : NULL;
+}
+
+static inline void s3c_gpiolib_track(struct samsung_gpio_chip *chip) { }
+#endif
+
+#ifdef CONFIG_PM
+extern struct samsung_gpio_pm samsung_gpio_pm_1bit;
+extern struct samsung_gpio_pm samsung_gpio_pm_2bit;
+extern struct samsung_gpio_pm samsung_gpio_pm_4bit;
+#define __gpio_pm(x) x
+#else
+#define samsung_gpio_pm_1bit NULL
+#define samsung_gpio_pm_2bit NULL
+#define samsung_gpio_pm_4bit NULL
+#define __gpio_pm(x) NULL
+
+#endif /* CONFIG_PM */
+
+/* locking wrappers to deal with multiple access to the same gpio bank */
+#define samsung_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl)
+#define samsung_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl)
+
+#endif /* __PLAT_SAMSUNG_GPIO_CORE_H */