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