arch/arm/mach-s3c/setup-usb-phy-s3c64xx.c

Source file repositories/reference/linux-study-clean/arch/arm/mach-s3c/setup-usb-phy-s3c64xx.c

File Facts

System
Linux kernel
Corpus path
arch/arm/mach-s3c/setup-usb-phy-s3c64xx.c
Extension
.c
Size
2013 bytes
Lines
91
Domain
Architecture Layer
Bucket
arch/arm
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

switch (clk_get_rate(xusbxti)) {
		case 12 * MHZ:
			phyclk |= S3C_PHYCLK_CLKSEL_12M;
			break;
		case 24 * MHZ:
			phyclk |= S3C_PHYCLK_CLKSEL_24M;
			break;
		default:
		case 48 * MHZ:
			/* default reference clock */
			break;
		}
		clk_put(xusbxti);
	}

	/* TODO: select external clock/oscillator */
	writel(phyclk | S3C_PHYCLK_CLK_FORCE, S3C_PHYCLK);

	/* set to normal OTG PHY */
	writel((readl(S3C_PHYPWR) & ~S3C_PHYPWR_NORMAL_MASK), S3C_PHYPWR);
	mdelay(1);

	/* reset OTG PHY and Link */
	writel(S3C_RSTCON_PHY | S3C_RSTCON_HCLK | S3C_RSTCON_PHYCLK,
			S3C_RSTCON);
	udelay(20);	/* at-least 10uS */
	writel(0, S3C_RSTCON);

	return 0;
}

static int s3c_usb_otgphy_exit(struct platform_device *pdev)
{
	writel((readl(S3C_PHYPWR) | S3C_PHYPWR_ANALOG_POWERDOWN |
				S3C_PHYPWR_OTG_DISABLE), S3C_PHYPWR);

	writel(readl(S3C64XX_OTHERS) & ~S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);

	return 0;
}

int s3c_usb_phy_init(struct platform_device *pdev, int type)
{
	if (type == USB_PHY_TYPE_DEVICE)
		return s3c_usb_otgphy_init(pdev);

	return -EINVAL;
}

int s3c_usb_phy_exit(struct platform_device *pdev, int type)
{
	if (type == USB_PHY_TYPE_DEVICE)
		return s3c_usb_otgphy_exit(pdev);

	return -EINVAL;
}

Annotation

Implementation Notes