drivers/usb/dwc3/dwc3-qcom-legacy.c

Source file repositories/reference/linux-study-clean/drivers/usb/dwc3/dwc3-qcom-legacy.c

File Facts

System
Linux kernel
Corpus path
drivers/usb/dwc3/dwc3-qcom-legacy.c
Extension
.c
Size
22722 bytes
Lines
936
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 dwc3_qcom_port {
	int			qusb2_phy_irq;
	int			dp_hs_phy_irq;
	int			dm_hs_phy_irq;
	int			ss_phy_irq;
	enum usb_device_speed	usb2_speed;
};

struct dwc3_qcom {
	struct device		*dev;
	void __iomem		*qscratch_base;
	struct platform_device	*dwc3;
	struct clk		**clks;
	int			num_clocks;
	struct reset_control	*resets;
	struct dwc3_qcom_port	ports[DWC3_QCOM_MAX_PORTS];
	u8			num_ports;

	struct extcon_dev	*edev;
	struct extcon_dev	*host_edev;
	struct notifier_block	vbus_nb;
	struct notifier_block	host_nb;

	enum usb_dr_mode	mode;
	bool			is_suspended;
	bool			pm_suspended;
	struct icc_path		*icc_path_ddr;
	struct icc_path		*icc_path_apps;
};

static inline void dwc3_qcom_setbits(void __iomem *base, u32 offset, u32 val)
{
	u32 reg;

	reg = readl(base + offset);
	reg |= val;
	writel(reg, base + offset);

	/* ensure that above write is through */
	readl(base + offset);
}

static inline void dwc3_qcom_clrbits(void __iomem *base, u32 offset, u32 val)
{
	u32 reg;

	reg = readl(base + offset);
	reg &= ~val;
	writel(reg, base + offset);

	/* ensure that above write is through */
	readl(base + offset);
}

static void dwc3_qcom_vbus_override_enable(struct dwc3_qcom *qcom, bool enable)
{
	if (enable) {
		dwc3_qcom_setbits(qcom->qscratch_base, QSCRATCH_SS_PHY_CTRL,
				  LANE0_PWR_PRESENT);
		dwc3_qcom_setbits(qcom->qscratch_base, QSCRATCH_HS_PHY_CTRL,
				  UTMI_OTG_VBUS_VALID | SW_SESSVLD_SEL);
	} else {
		dwc3_qcom_clrbits(qcom->qscratch_base, QSCRATCH_SS_PHY_CTRL,
				  LANE0_PWR_PRESENT);
		dwc3_qcom_clrbits(qcom->qscratch_base, QSCRATCH_HS_PHY_CTRL,
				  UTMI_OTG_VBUS_VALID | SW_SESSVLD_SEL);
	}
}

static int dwc3_qcom_vbus_notifier(struct notifier_block *nb,
				   unsigned long event, void *ptr)
{
	struct dwc3_qcom *qcom = container_of(nb, struct dwc3_qcom, vbus_nb);

	/* enable vbus override for device mode */
	dwc3_qcom_vbus_override_enable(qcom, event);
	qcom->mode = event ? USB_DR_MODE_PERIPHERAL : USB_DR_MODE_HOST;

	return NOTIFY_DONE;
}

static int dwc3_qcom_host_notifier(struct notifier_block *nb,
				   unsigned long event, void *ptr)
{
	struct dwc3_qcom *qcom = container_of(nb, struct dwc3_qcom, host_nb);

	/* disable vbus override in host mode */
	dwc3_qcom_vbus_override_enable(qcom, !event);
	qcom->mode = event ? USB_DR_MODE_HOST : USB_DR_MODE_PERIPHERAL;

Annotation

Implementation Notes