drivers/usb/musb/da8xx.c

Source file repositories/reference/linux-study-clean/drivers/usb/musb/da8xx.c

File Facts

System
Linux kernel
Corpus path
drivers/usb/musb/da8xx.c
Extension
.c
Size
17748 bytes
Lines
650
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 da8xx_glue {
	struct device		*dev;
	struct platform_device	*musb;
	struct platform_device	*usb_phy;
	struct clk		*clk;
	struct phy		*phy;
};

/*
 * Because we don't set CTRL.UINT, it's "important" to:
 *	- not read/write INTRUSB/INTRUSBE (except during
 *	  initial setup, as a workaround);
 *	- use INTSET/INTCLR instead.
 */

/**
 * da8xx_musb_enable - enable interrupts
 */
static void da8xx_musb_enable(struct musb *musb)
{
	void __iomem *reg_base = musb->ctrl_base;
	u32 mask;

	/* Workaround: setup IRQs through both register sets. */
	mask = ((musb->epmask & DA8XX_USB_TX_EP_MASK) << DA8XX_INTR_TX_SHIFT) |
	       ((musb->epmask & DA8XX_USB_RX_EP_MASK) << DA8XX_INTR_RX_SHIFT) |
	       DA8XX_INTR_USB_MASK;
	musb_writel(reg_base, DA8XX_USB_INTR_MASK_SET_REG, mask);

	/* Force the DRVVBUS IRQ so we can start polling for ID change. */
	musb_writel(reg_base, DA8XX_USB_INTR_SRC_SET_REG,
			DA8XX_INTR_DRVVBUS << DA8XX_INTR_USB_SHIFT);
}

/**
 * da8xx_musb_disable - disable HDRC and flush interrupts
 */
static void da8xx_musb_disable(struct musb *musb)
{
	void __iomem *reg_base = musb->ctrl_base;

	musb_writel(reg_base, DA8XX_USB_INTR_MASK_CLEAR_REG,
		    DA8XX_INTR_USB_MASK |
		    DA8XX_INTR_TX_MASK | DA8XX_INTR_RX_MASK);
	musb_writel(reg_base, DA8XX_USB_END_OF_INTR_REG, 0);
}

#define portstate(stmt)		stmt

static void da8xx_musb_set_vbus(struct musb *musb, int is_on)
{
	WARN_ON(is_on && is_peripheral_active(musb));
}

#define	POLL_SECONDS	2

static void otg_timer(struct timer_list *t)
{
	struct musb		*musb = timer_container_of(musb, t,
							      dev_timer);
	void __iomem		*mregs = musb->mregs;
	u8			devctl;
	unsigned long		flags;

	/*
	 * We poll because DaVinci's won't expose several OTG-critical
	 * status change events (from the transceiver) otherwise.
	 */
	devctl = musb_readb(mregs, MUSB_DEVCTL);
	dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl,
		usb_otg_state_string(musb->xceiv->otg->state));

	spin_lock_irqsave(&musb->lock, flags);
	switch (musb->xceiv->otg->state) {
	case OTG_STATE_A_WAIT_BCON:
		devctl &= ~MUSB_DEVCTL_SESSION;
		musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);

		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
		if (devctl & MUSB_DEVCTL_BDEVICE) {
			musb->xceiv->otg->state = OTG_STATE_B_IDLE;
			MUSB_DEV_MODE(musb);
		} else {
			musb->xceiv->otg->state = OTG_STATE_A_IDLE;
			MUSB_HST_MODE(musb);
		}
		break;
	case OTG_STATE_A_WAIT_VFALL:
		/*
		 * Wait till VBUS falls below SessionEnd (~0.2 V); the 1.3

Annotation

Implementation Notes