drivers/reset/reset-k210.c

Source file repositories/reference/linux-study-clean/drivers/reset/reset-k210.c

File Facts

System
Linux kernel
Corpus path
drivers/reset/reset-k210.c
Extension
.c
Size
3017 bytes
Lines
132
Domain
Driver Families
Bucket
drivers/reset
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 k210_rst {
	struct regmap *map;
	struct reset_controller_dev rcdev;
};

static inline struct k210_rst *
to_k210_rst(struct reset_controller_dev *rcdev)
{
	return container_of(rcdev, struct k210_rst, rcdev);
}

static inline int k210_rst_assert(struct reset_controller_dev *rcdev,
				  unsigned long id)
{
	struct k210_rst *ksr = to_k210_rst(rcdev);

	return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 1);
}

static inline int k210_rst_deassert(struct reset_controller_dev *rcdev,
				    unsigned long id)
{
	struct k210_rst *ksr = to_k210_rst(rcdev);

	return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 0);
}

static int k210_rst_reset(struct reset_controller_dev *rcdev,
			  unsigned long id)
{
	int ret;

	ret = k210_rst_assert(rcdev, id);
	if (ret == 0) {
		udelay(10);
		ret = k210_rst_deassert(rcdev, id);
	}

	return ret;
}

static int k210_rst_status(struct reset_controller_dev *rcdev,
			   unsigned long id)
{
	struct k210_rst *ksr = to_k210_rst(rcdev);
	u32 reg, bit = BIT(id);
	int ret;

	ret = regmap_read(ksr->map, K210_SYSCTL_PERI_RESET, &reg);
	if (ret)
		return ret;

	return reg & bit;
}

static int k210_rst_xlate(struct reset_controller_dev *rcdev,
			  const struct of_phandle_args *reset_spec)
{
	unsigned long id = reset_spec->args[0];

	if (!(BIT(id) & K210_RST_MASK))
		return -EINVAL;

	return id;
}

static const struct reset_control_ops k210_rst_ops = {
	.assert		= k210_rst_assert,
	.deassert	= k210_rst_deassert,
	.reset		= k210_rst_reset,
	.status		= k210_rst_status,
};

static int k210_rst_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *parent_np;
	struct k210_rst *ksr;

	dev_info(dev, "K210 reset controller\n");

	ksr = devm_kzalloc(dev, sizeof(*ksr), GFP_KERNEL);
	if (!ksr)
		return -ENOMEM;

	parent_np = of_get_parent(dev->of_node);
	ksr->map = syscon_node_to_regmap(parent_np);
	of_node_put(parent_np);
	if (IS_ERR(ksr->map))
		return PTR_ERR(ksr->map);

Annotation

Implementation Notes