static int npcm_usb_reset()

in reset-npcm.c [150:229]

• 61 lines of code
• 6 McCabe index (conditional complexity)

static int npcm_usb_reset(struct platform_device *pdev, struct npcm_rc_data *rc)
{
	u32 mdlr, iprst1, iprst2, iprst3;
	struct device *dev = &pdev->dev;
	struct regmap *gcr_regmap;
	u32 ipsrst1_bits = 0;
	u32 ipsrst2_bits = NPCM_IPSRST2_USB_HOST;
	u32 ipsrst3_bits = 0;
	const char *gcr_dt;

	gcr_dt = (const char *)
	of_match_device(dev->driver->of_match_table, dev)->data;

	gcr_regmap = syscon_regmap_lookup_by_compatible(gcr_dt);
	if (IS_ERR(gcr_regmap)) {
		dev_err(&pdev->dev, "Failed to find %s\n", gcr_dt);
		return PTR_ERR(gcr_regmap);
	}

	/* checking which USB device is enabled */
	regmap_read(gcr_regmap, NPCM_MDLR_OFFSET, &mdlr);
	if (!(mdlr & NPCM_MDLR_USBD0))
		ipsrst3_bits |= NPCM_IPSRST3_USBD0;
	if (!(mdlr & NPCM_MDLR_USBD1))
		ipsrst1_bits |= NPCM_IPSRST1_USBD1;
	if (!(mdlr & NPCM_MDLR_USBD2_4))
		ipsrst1_bits |= (NPCM_IPSRST1_USBD2 |
				 NPCM_IPSRST1_USBD3 |
				 NPCM_IPSRST1_USBD4);
	if (!(mdlr & NPCM_MDLR_USBD0)) {
		ipsrst1_bits |= (NPCM_IPSRST1_USBD5 |
				 NPCM_IPSRST1_USBD6);
		ipsrst3_bits |= (NPCM_IPSRST3_USBD7 |
				 NPCM_IPSRST3_USBD8 |
				 NPCM_IPSRST3_USBD9);
	}

	/* assert reset USB PHY and USB devices */
	iprst1 = readl(rc->base + NPCM_IPSRST1);
	iprst2 = readl(rc->base + NPCM_IPSRST2);
	iprst3 = readl(rc->base + NPCM_IPSRST3);

	iprst1 |= ipsrst1_bits;
	iprst2 |= ipsrst2_bits;
	iprst3 |= (ipsrst3_bits | NPCM_IPSRST3_USBPHY1 |
		   NPCM_IPSRST3_USBPHY2);

	writel(iprst1, rc->base + NPCM_IPSRST1);
	writel(iprst2, rc->base + NPCM_IPSRST2);
	writel(iprst3, rc->base + NPCM_IPSRST3);

	/* clear USB PHY RS bit */
	regmap_update_bits(gcr_regmap, NPCM_USB1PHYCTL_OFFSET,
			   NPCM_USBXPHYCTL_RS, 0);
	regmap_update_bits(gcr_regmap, NPCM_USB2PHYCTL_OFFSET,
			   NPCM_USBXPHYCTL_RS, 0);

	/* deassert reset USB PHY */
	iprst3 &= ~(NPCM_IPSRST3_USBPHY1 | NPCM_IPSRST3_USBPHY2);
	writel(iprst3, rc->base + NPCM_IPSRST3);

	udelay(50);

	/* set USB PHY RS bit */
	regmap_update_bits(gcr_regmap, NPCM_USB1PHYCTL_OFFSET,
			   NPCM_USBXPHYCTL_RS, NPCM_USBXPHYCTL_RS);
	regmap_update_bits(gcr_regmap, NPCM_USB2PHYCTL_OFFSET,
			   NPCM_USBXPHYCTL_RS, NPCM_USBXPHYCTL_RS);

	/* deassert reset USB devices*/
	iprst1 &= ~ipsrst1_bits;
	iprst2 &= ~ipsrst2_bits;
	iprst3 &= ~ipsrst3_bits;

	writel(iprst1, rc->base + NPCM_IPSRST1);
	writel(iprst2, rc->base + NPCM_IPSRST2);
	writel(iprst3, rc->base + NPCM_IPSRST3);

	return 0;
}