drivers/reset/reset-pistachio.c

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

File Facts

System
Linux kernel
Corpus path
drivers/reset/reset-pistachio.c
Extension
.c
Size
3357 bytes
Lines
137
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 pistachio_reset_data {
	struct reset_controller_dev	rcdev;
	struct regmap			*periph_regs;
};

static inline int pistachio_reset_shift(unsigned long id)
{
	switch (id) {
	case PISTACHIO_RESET_I2C0:
	case PISTACHIO_RESET_I2C1:
	case PISTACHIO_RESET_I2C2:
	case PISTACHIO_RESET_I2C3:
	case PISTACHIO_RESET_I2S_IN:
	case PISTACHIO_RESET_PRL_OUT:
	case PISTACHIO_RESET_SPDIF_OUT:
	case PISTACHIO_RESET_SPI:
	case PISTACHIO_RESET_PWM_PDM:
	case PISTACHIO_RESET_UART0:
	case PISTACHIO_RESET_UART1:
	case PISTACHIO_RESET_QSPI:
	case PISTACHIO_RESET_MDC:
	case PISTACHIO_RESET_SDHOST:
	case PISTACHIO_RESET_ETHERNET:
	case PISTACHIO_RESET_IR:
	case PISTACHIO_RESET_HASH:
	case PISTACHIO_RESET_TIMER:
		return id;
	case PISTACHIO_RESET_I2S_OUT:
	case PISTACHIO_RESET_SPDIF_IN:
	case PISTACHIO_RESET_EVT:
		return id + 6;
	case PISTACHIO_RESET_USB_H:
	case PISTACHIO_RESET_USB_PR:
	case PISTACHIO_RESET_USB_PHY_PR:
	case PISTACHIO_RESET_USB_PHY_PON:
		return id + 7;
	default:
		return -EINVAL;
	}
}

static int pistachio_reset_assert(struct reset_controller_dev *rcdev,
				  unsigned long id)
{
	struct pistachio_reset_data *rd;
	u32 mask;
	int shift;

	rd = container_of(rcdev, struct pistachio_reset_data, rcdev);
	shift = pistachio_reset_shift(id);
	if (shift < 0)
		return shift;
	mask = BIT(shift);

	return regmap_update_bits(rd->periph_regs, PISTACHIO_SOFT_RESET,
				  mask, mask);
}

static int pistachio_reset_deassert(struct reset_controller_dev *rcdev,
				    unsigned long id)
{
	struct pistachio_reset_data *rd;
	u32 mask;
	int shift;

	rd = container_of(rcdev, struct pistachio_reset_data, rcdev);
	shift = pistachio_reset_shift(id);
	if (shift < 0)
		return shift;
	mask = BIT(shift);

	return regmap_update_bits(rd->periph_regs, PISTACHIO_SOFT_RESET,
				  mask, 0);
}

static const struct reset_control_ops pistachio_reset_ops = {
	.assert		= pistachio_reset_assert,
	.deassert	= pistachio_reset_deassert,
};

static int pistachio_reset_probe(struct platform_device *pdev)
{
	struct pistachio_reset_data *rd;
	struct device *dev = &pdev->dev;
	struct device_node *np = pdev->dev.of_node;

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

Annotation

Implementation Notes