drivers/gpio/gpio-ftgpio010.c

Source file repositories/reference/linux-study-clean/drivers/gpio/gpio-ftgpio010.c

File Facts

System
Linux kernel
Corpus path
drivers/gpio/gpio-ftgpio010.c
Extension
.c
Size
8850 bytes
Lines
335
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 ftgpio_gpio {
	struct device *dev;
	struct gpio_generic_chip chip;
	void __iomem *base;
	struct clk *clk;
};

static void ftgpio_gpio_ack_irq(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);

	writel(BIT(irqd_to_hwirq(d)), g->base + GPIO_INT_CLR);
}

static void ftgpio_gpio_mask_irq(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	u32 val;

	val = readl(g->base + GPIO_INT_EN);
	val &= ~BIT(irqd_to_hwirq(d));
	writel(val, g->base + GPIO_INT_EN);
	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
}

static void ftgpio_gpio_unmask_irq(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	u32 val;

	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
	val = readl(g->base + GPIO_INT_EN);
	val |= BIT(irqd_to_hwirq(d));
	writel(val, g->base + GPIO_INT_EN);
}

static int ftgpio_gpio_set_irq_type(struct irq_data *d, unsigned int type)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	u32 mask = BIT(irqd_to_hwirq(d));
	u32 reg_both, reg_level, reg_type;

	reg_type = readl(g->base + GPIO_INT_TYPE);
	reg_level = readl(g->base + GPIO_INT_LEVEL);
	reg_both = readl(g->base + GPIO_INT_BOTH_EDGE);

	switch (type) {
	case IRQ_TYPE_EDGE_BOTH:
		irq_set_handler_locked(d, handle_edge_irq);
		reg_type &= ~mask;
		reg_both |= mask;
		break;
	case IRQ_TYPE_EDGE_RISING:
		irq_set_handler_locked(d, handle_edge_irq);
		reg_type &= ~mask;
		reg_both &= ~mask;
		reg_level &= ~mask;
		break;
	case IRQ_TYPE_EDGE_FALLING:
		irq_set_handler_locked(d, handle_edge_irq);
		reg_type &= ~mask;
		reg_both &= ~mask;
		reg_level |= mask;
		break;
	case IRQ_TYPE_LEVEL_HIGH:
		irq_set_handler_locked(d, handle_level_irq);
		reg_type |= mask;
		reg_level &= ~mask;
		break;
	case IRQ_TYPE_LEVEL_LOW:
		irq_set_handler_locked(d, handle_level_irq);
		reg_type |= mask;
		reg_level |= mask;
		break;
	default:
		irq_set_handler_locked(d, handle_bad_irq);
		return -EINVAL;
	}

	writel(reg_type, g->base + GPIO_INT_TYPE);
	writel(reg_level, g->base + GPIO_INT_LEVEL);
	writel(reg_both, g->base + GPIO_INT_BOTH_EDGE);

	ftgpio_gpio_ack_irq(d);

	return 0;

Annotation

Implementation Notes