drivers/usb/cdns3/cdns3-starfive.c

Source file repositories/reference/linux-study-clean/drivers/usb/cdns3/cdns3-starfive.c

File Facts

System
Linux kernel
Corpus path
drivers/usb/cdns3/cdns3-starfive.c
Extension
.c
Size
5879 bytes
Lines
245
Domain
Driver Families
Bucket
drivers/usb
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 cdns_starfive {
	struct device *dev;
	struct regmap *stg_syscon;
	struct reset_control *resets;
	struct clk_bulk_data *clks;
	int num_clks;
	u32 stg_usb_mode;
};

static void cdns_mode_init(struct platform_device *pdev,
			   struct cdns_starfive *data)
{
	enum usb_dr_mode mode;

	regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
			   USB_MISC_CFG_MASK,
			   USB_SUSPENDM_BYPS | USB_PLL_EN | USB_REFCLK_MODE);

	/* dr mode setting */
	mode = usb_get_dr_mode(&pdev->dev);

	switch (mode) {
	case USB_DR_MODE_HOST:
		regmap_update_bits(data->stg_syscon,
				   data->stg_usb_mode,
				   USB_STRAP_MASK,
				   USB_STRAP_HOST);
		regmap_update_bits(data->stg_syscon,
				   data->stg_usb_mode,
				   USB_SUSPENDM_MASK,
				   USB_SUSPENDM_HOST);
		break;

	case USB_DR_MODE_PERIPHERAL:
		regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
				   USB_STRAP_MASK, USB_STRAP_DEVICE);
		regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
				   USB_SUSPENDM_MASK, 0);
		break;
	default:
		break;
	}
}

static int cdns_clk_rst_init(struct cdns_starfive *data)
{
	int ret;

	ret = clk_bulk_prepare_enable(data->num_clks, data->clks);
	if (ret)
		return dev_err_probe(data->dev, ret,
				     "failed to enable clocks\n");

	ret = reset_control_deassert(data->resets);
	if (ret) {
		dev_err(data->dev, "failed to reset clocks\n");
		goto err_clk_init;
	}

	return ret;

err_clk_init:
	clk_bulk_disable_unprepare(data->num_clks, data->clks);
	return ret;
}

static void cdns_clk_rst_deinit(struct cdns_starfive *data)
{
	reset_control_assert(data->resets);
	clk_bulk_disable_unprepare(data->num_clks, data->clks);
}

static int cdns_starfive_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct cdns_starfive *data;
	unsigned int args;
	int ret;

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

	data->dev = dev;

	data->stg_syscon =
		syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
						     "starfive,stg-syscon", 1, &args);

	if (IS_ERR(data->stg_syscon))

Annotation

Implementation Notes