drivers/phy/broadcom/phy-bcm-ns-usb2.c

Source file repositories/reference/linux-study-clean/drivers/phy/broadcom/phy-bcm-ns-usb2.c

File Facts

System
Linux kernel
Corpus path
drivers/phy/broadcom/phy-bcm-ns-usb2.c
Extension
.c
Size
3659 bytes
Lines
143
Domain
Driver Families
Bucket
drivers/phy
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 bcm_ns_usb2 {
	struct device *dev;
	struct clk *ref_clk;
	struct phy *phy;
	struct regmap *clkset;
	void __iomem *base;
};

static int bcm_ns_usb2_phy_init(struct phy *phy)
{
	struct bcm_ns_usb2 *usb2 = phy_get_drvdata(phy);
	struct device *dev = usb2->dev;
	u32 ref_clk_rate, usb2ctl, usb_pll_ndiv, usb_pll_pdiv;
	int err = 0;

	err = clk_prepare_enable(usb2->ref_clk);
	if (err < 0) {
		dev_err(dev, "Failed to prepare ref clock: %d\n", err);
		goto err_out;
	}

	ref_clk_rate = clk_get_rate(usb2->ref_clk);
	if (!ref_clk_rate) {
		dev_err(dev, "Failed to get ref clock rate\n");
		err = -EINVAL;
		goto err_clk_off;
	}

	usb2ctl = readl(usb2->base);

	if (usb2ctl & BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK) {
		usb_pll_pdiv = usb2ctl;
		usb_pll_pdiv &= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK;
		usb_pll_pdiv >>= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_SHIFT;
	} else {
		usb_pll_pdiv = 1 << 3;
	}

	/* Calculate ndiv based on a solid 1920 MHz that is for USB2 PHY */
	usb_pll_ndiv = (1920000000 * usb_pll_pdiv) / ref_clk_rate;

	/* Unlock DMU PLL settings with some magic value */
	regmap_write(usb2->clkset, 0, 0x0000ea68);

	/* Write USB 2.0 PLL control setting */
	usb2ctl &= ~BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_MASK;
	usb2ctl |= usb_pll_ndiv << BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_SHIFT;

	writel(usb2ctl, usb2->base);

	/* Lock DMU PLL settings */
	regmap_write(usb2->clkset, 0, 0x00000000);

err_clk_off:
	clk_disable_unprepare(usb2->ref_clk);
err_out:
	return err;
}

static const struct phy_ops ops = {
	.init		= bcm_ns_usb2_phy_init,
	.owner		= THIS_MODULE,
};

static int bcm_ns_usb2_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct bcm_ns_usb2 *usb2;
	struct phy_provider *phy_provider;

	usb2 = devm_kzalloc(&pdev->dev, sizeof(*usb2), GFP_KERNEL);
	if (!usb2)
		return -ENOMEM;
	usb2->dev = dev;

	usb2->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(usb2->base)) {
		dev_err(dev, "Failed to map control reg\n");
		return PTR_ERR(usb2->base);
	}

	usb2->clkset = syscon_regmap_lookup_by_phandle(dev->of_node,
						       "brcm,syscon-clkset");
	if (IS_ERR(usb2->clkset)) {
		dev_err(dev, "Failed to lookup clkset regmap\n");
		return PTR_ERR(usb2->clkset);
	}

	usb2->ref_clk = devm_clk_get(dev, "phy-ref-clk");
	if (IS_ERR(usb2->ref_clk)) {

Annotation

Implementation Notes