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

   1/* linux/arch/arm/plat-s3c/include/plat/gpio-core.h
   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 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12*/
  13
  14#ifndef __PLAT_SAMSUNG_GPIO_CORE_H
  15#define __PLAT_SAMSUNG_GPIO_CORE_H
  16
  17/* Bring in machine-local definitions, especially S3C_GPIO_END */
  18#include <mach/gpio-samsung.h>
  19
  20#define GPIOCON_OFF     (0x00)
  21#define GPIODAT_OFF     (0x04)
  22
  23#define con_4bit_shift(__off) ((__off) * 4)
  24
  25/* Define the core gpiolib support functions that the s3c platforms may
  26 * need to extend or change depending on the hardware and the s3c chip
  27 * selected at build or found at run time.
  28 *
  29 * These definitions are not intended for driver inclusion, there is
  30 * nothing here that should not live outside the platform and core
  31 * specific code.
  32*/
  33
  34struct samsung_gpio_chip;
  35
  36/**
  37 * struct samsung_gpio_pm - power management (suspend/resume) information
  38 * @save: Routine to save the state of the GPIO block
  39 * @resume: Routine to resume the GPIO block.
  40 */
  41struct samsung_gpio_pm {
  42        void (*save)(struct samsung_gpio_chip *chip);
  43        void (*resume)(struct samsung_gpio_chip *chip);
  44};
  45
  46struct samsung_gpio_cfg;
  47
  48/**
  49 * struct samsung_gpio_chip - wrapper for specific implementation of gpio
  50 * @chip: The chip structure to be exported via gpiolib.
  51 * @base: The base pointer to the gpio configuration registers.
  52 * @group: The group register number for gpio interrupt support.
  53 * @irq_base: The base irq number.
  54 * @config: special function and pull-resistor control information.
  55 * @lock: Lock for exclusive access to this gpio bank.
  56 * @pm_save: Save information for suspend/resume support.
  57 * @bitmap_gpio_int: Bitmap for representing GPIO interrupt or not.
  58 *
  59 * This wrapper provides the necessary information for the Samsung
  60 * specific gpios being registered with gpiolib.
  61 *
  62 * The lock protects each gpio bank from multiple access of the shared
  63 * configuration registers, or from reading of data whilst another thread
  64 * is writing to the register set.
  65 *
  66 * Each chip has its own lock to avoid any  contention between different
  67 * CPU cores trying to get one lock for different GPIO banks, where each
  68 * bank of GPIO has its own register space and configuration registers.
  69 */
  70struct samsung_gpio_chip {
  71        struct gpio_chip        chip;
  72        struct samsung_gpio_cfg *config;
  73        struct samsung_gpio_pm  *pm;
  74        void __iomem            *base;
  75        int                     irq_base;
  76        int                     group;
  77        spinlock_t               lock;
  78#ifdef CONFIG_PM
  79        u32                     pm_save[4];
  80#endif
  81        u32                     bitmap_gpio_int;
  82};
  83
  84static inline struct samsung_gpio_chip *to_samsung_gpio(struct gpio_chip *gpc)
  85{
  86        return container_of(gpc, struct samsung_gpio_chip, chip);
  87}
  88
  89/**
  90 * samsung_gpiolib_to_irq - convert gpio pin to irq number
  91 * @chip: The gpio chip that the pin belongs to.
  92 * @offset: The offset of the pin in the chip.
  93 *
  94 * This helper returns the irq number calculated from the chip->irq_base and
  95 * the provided offset.
  96 */
  97extern int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset);
  98
  99/* exported for core SoC support to change */
 100extern struct samsung_gpio_cfg s3c24xx_gpiocfg_default;
 101
 102#ifdef CONFIG_S3C_GPIO_TRACK
 103extern struct samsung_gpio_chip *s3c_gpios[S3C_GPIO_END];
 104
 105static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int chip)
 106{
 107        return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL;
 108}
 109#else
 110/* machine specific code should provide samsung_gpiolib_getchip */
 111
 112extern struct samsung_gpio_chip s3c24xx_gpios[];
 113
 114static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int pin)
 115{
 116        struct samsung_gpio_chip *chip;
 117
 118        if (pin > S3C_GPIO_END)
 119                return NULL;
 120
 121        chip = &s3c24xx_gpios[pin/32];
 122        return ((pin - chip->chip.base) < chip->chip.ngpio) ? chip : NULL;
 123}
 124
 125static inline void s3c_gpiolib_track(struct samsung_gpio_chip *chip) { }
 126#endif
 127
 128#ifdef CONFIG_PM
 129extern struct samsung_gpio_pm samsung_gpio_pm_1bit;
 130extern struct samsung_gpio_pm samsung_gpio_pm_2bit;
 131extern struct samsung_gpio_pm samsung_gpio_pm_4bit;
 132#define __gpio_pm(x) x
 133#else
 134#define samsung_gpio_pm_1bit NULL
 135#define samsung_gpio_pm_2bit NULL
 136#define samsung_gpio_pm_4bit NULL
 137#define __gpio_pm(x) NULL
 138
 139#endif /* CONFIG_PM */
 140
 141/* locking wrappers to deal with multiple access to the same gpio bank */
 142#define samsung_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl)
 143#define samsung_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl)
 144
 145#endif /* __PLAT_SAMSUNG_GPIO_CORE_H */
 146