arch/arm/mach-s3c/gpio-core.h

Source file repositories/reference/linux-study-clean/arch/arm/mach-s3c/gpio-core.h

File Facts

System
Linux kernel
Corpus path
arch/arm/mach-s3c/gpio-core.h
Extension
.h
Size
4327 bytes
Lines
140
Domain
Architecture Layer
Bucket
arch/arm
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

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);

#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

Annotation

Implementation Notes