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 "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 31 struct 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 */ 38 struct samsung_gpio_pm { 39 void (*save)(struct samsung_gpio_chip *chip); 40 void (*resume)(struct samsung_gpio_chip *chip); 41 }; 42 43 struct 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 */ 67 struct 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 81 static 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 */ 94 extern int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset); 95 96 /* exported for core SoC support to change */ 97 extern struct samsung_gpio_cfg s3c24xx_gpiocfg_default; 98 99 #ifdef CONFIG_S3C_GPIO_TRACK 100 extern struct samsung_gpio_chip *s3c_gpios[S3C_GPIO_END]; 101 102 static 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 */ 108 109 extern struct samsung_gpio_chip s3c24xx_gpios[]; 110 111 static 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 } 121 122 static inline void s3c_gpiolib_track(struct samsung_gpio_chip *chip) { } 123 #endif 124 125 #ifdef CONFIG_PM 126 extern struct samsung_gpio_pm samsung_gpio_pm_1bit; 127 extern struct samsung_gpio_pm samsung_gpio_pm_2bit; 128 extern 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