diff options
Diffstat (limited to 'arch/arm/mach-s3c/gpio-core.h')
| -rw-r--r-- | arch/arm/mach-s3c/gpio-core.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c/gpio-core.h b/arch/arm/mach-s3c/gpio-core.h new file mode 100644 index 000000000000..b361c8c0d669 --- /dev/null +++ b/arch/arm/mach-s3c/gpio-core.h @@ -0,0 +1,142 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright 2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C Platform - GPIO core + */ + +#ifndef __PLAT_SAMSUNG_GPIO_CORE_H +#define __PLAT_SAMSUNG_GPIO_CORE_H + +/* Bring in machine-local definitions, especially S3C_GPIO_END */ +#include "gpio-samsung.h" +#include <linux/gpio/driver.h> + +#define GPIOCON_OFF (0x00) +#define GPIODAT_OFF (0x04) + +#define con_4bit_shift(__off) ((__off) * 4) + +/* Define the core gpiolib support functions that the s3c platforms may + * need to extend or change depending on the hardware and the s3c chip + * selected at build or found at run time. + * + * These definitions are not intended for driver inclusion, there is + * nothing here that should not live outside the platform and core + * specific code. +*/ + +struct samsung_gpio_chip; + +/** + * struct samsung_gpio_pm - power management (suspend/resume) information + * @save: Routine to save the state of the GPIO block + * @resume: Routine to resume the GPIO block. + */ +struct samsung_gpio_pm { + void (*save)(struct samsung_gpio_chip *chip); + void (*resume)(struct samsung_gpio_chip *chip); +}; + +struct samsung_gpio_cfg; + +/** + * struct samsung_gpio_chip - wrapper for specific implementation of gpio + * @chip: The chip structure to be exported via gpiolib. + * @base: The base pointer to the gpio configuration registers. + * @group: The group register number for gpio interrupt support. + * @irq_base: The base irq number. + * @config: special function and pull-resistor control information. + * @lock: Lock for exclusive access to this gpio bank. + * @pm_save: Save information for suspend/resume support. + * @bitmap_gpio_int: Bitmap for representing GPIO interrupt or not. + * + * This wrapper provides the necessary information for the Samsung + * specific gpios being registered with gpiolib. + * + * The lock protects each gpio bank from multiple access of the shared + * configuration registers, or from reading of data whilst another thread + * is writing to the register set. + * + * Each chip has its own lock to avoid any contention between different + * CPU cores trying to get one lock for different GPIO banks, where each + * bank of GPIO has its own register space and configuration registers. + */ +struct samsung_gpio_chip { + struct gpio_chip chip; + struct samsung_gpio_cfg *config; + struct samsung_gpio_pm *pm; + void __iomem *base; + int irq_base; + int group; + spinlock_t lock; +#ifdef CONFIG_PM + u32 pm_save[4]; +#endif + u32 bitmap_gpio_int; +}; + +static inline struct samsung_gpio_chip *to_samsung_gpio(struct gpio_chip *gpc) +{ + return container_of(gpc, struct samsung_gpio_chip, chip); +} + +/** + * samsung_gpiolib_to_irq - convert gpio pin to irq number + * @chip: The gpio chip that the pin belongs to. + * @offset: The offset of the pin in the chip. + * + * This helper returns the irq number calculated from the chip->irq_base and + * the provided offset. + */ +extern int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset); + +/* exported for core SoC support to change */ +extern struct samsung_gpio_cfg s3c24xx_gpiocfg_default; + +#ifdef CONFIG_S3C_GPIO_TRACK +extern struct samsung_gpio_chip *s3c_gpios[S3C_GPIO_END]; + +static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int chip) +{ + return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL; +} +#else +/* machine specific code should provide samsung_gpiolib_getchip */ + +extern struct samsung_gpio_chip s3c24xx_gpios[]; + +static inline struct samsung_gpio_chip *samsung_gpiolib_getchip(unsigned int pin) +{ + struct samsung_gpio_chip *chip; + + if (pin > S3C_GPIO_END) + return NULL; + + chip = &s3c24xx_gpios[pin/32]; + return ((pin - chip->chip.base) < chip->chip.ngpio) ? chip : NULL; +} + +static inline void s3c_gpiolib_track(struct samsung_gpio_chip *chip) { } +#endif + +#ifdef CONFIG_PM +extern struct samsung_gpio_pm samsung_gpio_pm_1bit; +extern struct samsung_gpio_pm samsung_gpio_pm_2bit; +extern struct samsung_gpio_pm samsung_gpio_pm_4bit; +#define __gpio_pm(x) x +#else +#define samsung_gpio_pm_1bit NULL +#define samsung_gpio_pm_2bit NULL +#define samsung_gpio_pm_4bit NULL +#define __gpio_pm(x) NULL + +#endif /* CONFIG_PM */ + +/* locking wrappers to deal with multiple access to the same gpio bank */ +#define samsung_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl) +#define samsung_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl) + +#endif /* __PLAT_SAMSUNG_GPIO_CORE_H */ |