drivers/gpio/gpio-mb86s7x.c

Source file repositories/reference/linux-study-clean/drivers/gpio/gpio-mb86s7x.c

File Facts

System
Linux kernel
Corpus path
drivers/gpio/gpio-mb86s7x.c
Extension
.c
Size
5592 bytes
Lines
237
Domain
Driver Families
Bucket
drivers/gpio
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mb86s70_gpio_chip {
	struct gpio_chip gc;
	void __iomem *base;
	spinlock_t lock;
};

static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio)
{
	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
	unsigned long flags;
	u32 val;

	spin_lock_irqsave(&gchip->lock, flags);

	val = readl(gchip->base + PFR(gpio));
	val &= ~OFFSET(gpio);
	writel(val, gchip->base + PFR(gpio));

	spin_unlock_irqrestore(&gchip->lock, flags);

	return 0;
}

static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio)
{
	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
	unsigned long flags;
	u32 val;

	spin_lock_irqsave(&gchip->lock, flags);

	val = readl(gchip->base + PFR(gpio));
	val |= OFFSET(gpio);
	writel(val, gchip->base + PFR(gpio));

	spin_unlock_irqrestore(&gchip->lock, flags);
}

static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
{
	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
	unsigned long flags;
	unsigned char val;

	spin_lock_irqsave(&gchip->lock, flags);

	val = readl(gchip->base + DDR(gpio));
	val &= ~OFFSET(gpio);
	writel(val, gchip->base + DDR(gpio));

	spin_unlock_irqrestore(&gchip->lock, flags);

	return 0;
}

static int mb86s70_gpio_direction_output(struct gpio_chip *gc,
					 unsigned gpio, int value)
{
	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
	unsigned long flags;
	unsigned char val;

	spin_lock_irqsave(&gchip->lock, flags);

	val = readl(gchip->base + PDR(gpio));
	if (value)
		val |= OFFSET(gpio);
	else
		val &= ~OFFSET(gpio);
	writel(val, gchip->base + PDR(gpio));

	val = readl(gchip->base + DDR(gpio));
	val |= OFFSET(gpio);
	writel(val, gchip->base + DDR(gpio));

	spin_unlock_irqrestore(&gchip->lock, flags);

	return 0;
}

static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio)
{
	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);

	return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio));
}

static int mb86s70_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
{
	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);

Annotation

Implementation Notes