LXR linux/arch/arm/plat-samsung/include/plat/gpio-core.h

   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 */
 143