drivers/reset/reset-a10sr.c

Source file repositories/reference/linux-study-clean/drivers/reset/reset-a10sr.c

File Facts

System
Linux kernel
Corpus path
drivers/reset/reset-a10sr.c
Extension
.c
Size
3285 bytes
Lines
129
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 a10sr_reset {
	struct reset_controller_dev     rcdev;
	struct regmap *regmap;
};

static inline struct a10sr_reset *to_a10sr_rst(struct reset_controller_dev *rc)
{
	return container_of(rc, struct a10sr_reset, rcdev);
}

static inline int a10sr_reset_shift(unsigned long id)
{
	switch (id) {
	case A10SR_RESET_ENET_HPS:
		return 1;
	case A10SR_RESET_PCIE:
	case A10SR_RESET_FILE:
	case A10SR_RESET_BQSPI:
	case A10SR_RESET_USB:
		return id + 11;
	default:
		return -EINVAL;
	}
}

static int a10sr_reset_update(struct reset_controller_dev *rcdev,
			      unsigned long id, bool assert)
{
	struct a10sr_reset *a10r = to_a10sr_rst(rcdev);
	int offset = a10sr_reset_shift(id);
	u8 mask = ALTR_A10SR_REG_BIT_MASK(offset);
	int index = ALTR_A10SR_HPS_RST_REG + ALTR_A10SR_REG_OFFSET(offset);

	return regmap_update_bits(a10r->regmap, index, mask, assert ? 0 : mask);
}

static int a10sr_reset_assert(struct reset_controller_dev *rcdev,
			      unsigned long id)
{
	return a10sr_reset_update(rcdev, id, true);
}

static int a10sr_reset_deassert(struct reset_controller_dev *rcdev,
				unsigned long id)
{
	return a10sr_reset_update(rcdev, id, false);
}

static int a10sr_reset_status(struct reset_controller_dev *rcdev,
			      unsigned long id)
{
	int ret;
	struct a10sr_reset *a10r = to_a10sr_rst(rcdev);
	int offset = a10sr_reset_shift(id);
	u8 mask = ALTR_A10SR_REG_BIT_MASK(offset);
	int index = ALTR_A10SR_HPS_RST_REG + ALTR_A10SR_REG_OFFSET(offset);
	unsigned int value;

	ret = regmap_read(a10r->regmap, index, &value);
	if (ret < 0)
		return ret;

	return !!(value & mask);
}

static const struct reset_control_ops a10sr_reset_ops = {
	.assert		= a10sr_reset_assert,
	.deassert	= a10sr_reset_deassert,
	.status		= a10sr_reset_status,
};

static int a10sr_reset_probe(struct platform_device *pdev)
{
	struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent);
	struct a10sr_reset *a10r;

	a10r = devm_kzalloc(&pdev->dev, sizeof(struct a10sr_reset),
			    GFP_KERNEL);
	if (!a10r)
		return -ENOMEM;

	a10r->rcdev.owner = THIS_MODULE;
	a10r->rcdev.nr_resets = A10SR_RESET_NUM;
	a10r->rcdev.ops = &a10sr_reset_ops;
	a10r->rcdev.of_node = pdev->dev.of_node;
	a10r->regmap = a10sr->regmap;

	platform_set_drvdata(pdev, a10r);

	return devm_reset_controller_register(&pdev->dev, &a10r->rcdev);

Annotation

Implementation Notes