1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright 2008 Simtec Electronics
  4 *	http://armlinux.simtec.co.uk/
  5 *	Ben Dooks <ben@simtec.co.uk>
  6 *
  7 * S3C Platform - GPIO core
  8 */
  9
 10#ifndef __PLAT_SAMSUNG_GPIO_CORE_H
 11#define __PLAT_SAMSUNG_GPIO_CORE_H
 12
 13/* Bring in machine-local definitions, especially S3C_GPIO_END */
 14#include <mach/gpio-samsung.h>
 15#include <linux/gpio/driver.h>
 16
 17#define GPIOCON_OFF	(0x00)
 18#define GPIODAT_OFF	(0x04)
 19
 20#define con_4bit_shift(__off) ((__off) * 4)
 21
 22/* Define the core gpiolib support functions that the s3c platforms may
 23 * need to extend or change depending on the hardware and the s3c chip
 24 * selected at build or found at run time.
 25 *
 26 * These definitions are not intended for driver inclusion, there is
 27 * nothing here that should not live outside the platform and core
 28 * specific code.
 29*/
 30
 31struct samsung_gpio_chip;
 32
 33/**
 34 * struct samsung_gpio_pm - power management (suspend/resume) information
 35 * @save: Routine to save the state of the GPIO block
 36 * @resume: Routine to resume the GPIO block.
 37 */
 38struct samsung_gpio_pm {
 39	void (*save)(struct samsung_gpio_chip *chip);
 40	void (*resume)(struct samsung_gpio_chip *chip);
 41};
 42
 43struct samsung_gpio_cfg;
 44
 45/**
 46 * struct samsung_gpio_chip - wrapper for specific implementation of gpio
 47 * @chip: The chip structure to be exported via gpiolib.
 48 * @base: The base pointer to the gpio configuration registers.
 49 * @group: The group register number for gpio interrupt support.
 50 * @irq_base: The base irq number.
 51 * @config: special function and pull-resistor control information.
 52 * @lock: Lock for exclusive access to this gpio bank.
 53 * @pm_save: Save information for suspend/resume support.
 54 * @bitmap_gpio_int: Bitmap for representing GPIO interrupt or not.
 55 *
 56 * This wrapper provides the necessary information for the Samsung
 57 * specific gpios being registered with gpiolib.
 58 *
 59 * The lock protects each gpio bank from multiple access of the shared
 60 * configuration registers, or from reading of data whilst another thread
 61 * is writing to the register set.
 62 *
 63 * Each chip has its own lock to avoid any  contention between different
 64 * CPU cores trying to get one lock for different GPIO banks, where each
 65 * bank of GPIO has its own register space and configuration registers.
 66 */
 67struct samsung_gpio_chip {
 68	struct gpio_chip	chip;
 69	struct samsung_gpio_cfg	*config;
 70	struct samsung_gpio_pm	*pm;
 71	void __iomem		*base;
 72	int			irq_base;
 73	int			group;
 74	spinlock_t		 lock;
 75#ifdef CONFIG_PM
 76	u32			pm_save[4];
 77#endif
 78	u32			bitmap_gpio_int;
 79};
 80
 81static inline struct samsung_gpio_chip *to_samsung_gpio(struct gpio_chip *gpc)
 82{
 83	return container_of(gpc, struct samsung_gpio_chip, chip);
 84}
 85
 86/**
 87 * samsung_gpiolib_to_irq - convert gpio pin to irq number
 88 * @chip: The gpio chip that the pin belongs to.
 89 * @offset: The offset of the pin in the chip.
 90 *
 91 * This helper returns the irq number calculated from the chip->irq_base and
 92 * the provided offset.
 93 */
 94extern int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset);
 95
 96/* exported for core SoC support to change */
 97extern struct samsung_gpio_cfg s3c24xx_gpiocfg_default;
 98
 99#ifdef CONFIG_S3C_GPIO_TRACK
100extern struct samsung_gpio_chip *s3c_gpios[S3C_GPIO_END];
101
102static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int chip)
103{
104	return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL;
105}
106#else
107/* machine specific code should provide samsung_gpiolib_getchip */
108
109extern struct samsung_gpio_chip s3c24xx_gpios[];
110
111static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int pin)
112{
113	struct samsung_gpio_chip *chip;
114
115	if (pin > S3C_GPIO_END)
116		return NULL;
117
118	chip = &s3c24xx_gpios[pin/32];
119	return ((pin - chip->chip.base) < chip->chip.ngpio) ? chip : NULL;
120}
121
122static inline void s3c_gpiolib_track(struct samsung_gpio_chip *chip) { }
123#endif
124
125#ifdef CONFIG_PM
126extern struct samsung_gpio_pm samsung_gpio_pm_1bit;
127extern struct samsung_gpio_pm samsung_gpio_pm_2bit;
128extern struct samsung_gpio_pm samsung_gpio_pm_4bit;
129#define __gpio_pm(x) x
130#else
131#define samsung_gpio_pm_1bit NULL
132#define samsung_gpio_pm_2bit NULL
133#define samsung_gpio_pm_4bit NULL
134#define __gpio_pm(x) NULL
135
136#endif /* CONFIG_PM */
137
138/* locking wrappers to deal with multiple access to the same gpio bank */
139#define samsung_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl)
140#define samsung_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl)
141
142#endif /* __PLAT_SAMSUNG_GPIO_CORE_H */