diff --git a/drivers/usb/phy/phy-tegra-usb.c b/drivers/usb/phy/phy-tegra-usb.c index 5fe4a5704bde..ccc2bf5274b4 100644 --- a/drivers/usb/phy/phy-tegra-usb.c +++ b/drivers/usb/phy/phy-tegra-usb.c @@ -329,6 +329,14 @@ static void utmi_phy_clk_disable(struct tegra_usb_phy *phy) unsigned long val; void __iomem *base = phy->regs; + /* + * The USB driver may have already initiated the phy clock + * disable so wait to see if the clock turns off and if not + * then proceed with gating the clock. + */ + if (utmi_wait_register(base + USB_SUSP_CTRL, USB_PHY_CLK_VALID, 0) == 0) + return; + if (phy->is_legacy_phy) { val = readl(base + USB_SUSP_CTRL); val |= USB_SUSP_SET; @@ -351,6 +359,15 @@ static void utmi_phy_clk_enable(struct tegra_usb_phy *phy) unsigned long val; void __iomem *base = phy->regs; + /* + * The USB driver may have already initiated the phy clock + * enable so wait to see if the clock turns on and if not + * then proceed with ungating the clock. + */ + if (utmi_wait_register(base + USB_SUSP_CTRL, USB_PHY_CLK_VALID, + USB_PHY_CLK_VALID) == 0) + return; + if (phy->is_legacy_phy) { val = readl(base + USB_SUSP_CTRL); val |= USB_SUSP_CLR;