Due to different controller issue of PHY_CLK_VALID in ULPI mode, in some cases, after set PHY_CLK_SEL, we should set USB_CTRL_USB_EN before checking PHY_CLK_VALID, otherwise PHY_CLK_VALID doesn't work. But in other cases USB_CTRL_USB_EN is already set previously and PHY_CLK_VALID is not valid once USB_CTRL_USB_EN is set. But since PHY_CLK_VALID is w1c, we can force clear USB_CTRL_USB_EN firstly after set PHY_CLK_SEL, then PHY_CLK_VALID status can be kept even we re-set USB_CTRL_USB_EN. Signed-off-by: Tiejun Chen <tiejun.chen@xxxxxxxxxxxxx> --- drivers/usb/host/ehci-fsl.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c index d81d2fc..57f2aa0 100644 --- a/drivers/usb/host/ehci-fsl.c +++ b/drivers/usb/host/ehci-fsl.c @@ -234,11 +234,20 @@ static int ehci_fsl_setup_phy(struct usb_hcd *hcd, /* controller version 1.6 or above */ setbits32(non_ehci + FSL_SOC_USB_CTRL, ULPI_PHY_CLK_SEL); + /* - * Due to controller issue of PHY_CLK_VALID in ULPI - * mode, we set USB_CTRL_USB_EN before checking - * PHY_CLK_VALID, otherwise PHY_CLK_VALID doesn't work. + * Due to different controller issue of PHY_CLK_VALID + * in ULPI mode, in some cases we should set + * USB_CTRL_USB_EN before checking PHY_CLK_VALID, + * otherwise PHY_CLK_VALID doesn't work. + * + * But in other cases USB_CTRL_USB_EN is already set + * and PHY_CLK_VALID is not valid once USB_CTRL_USB_EN + * is set. But since PHY_CLK_VALID is w1c, we can force + * clear USB_CTRL_USB_EN firstly then PHY_CLK_VALID + * status can be kept even we re-set USB_CTRL_USB_EN. */ + clrbits32(non_ehci + FSL_SOC_USB_CTRL, USB_CTRL_USB_EN); clrsetbits_be32(non_ehci + FSL_SOC_USB_CTRL, UTMI_PHY_EN, USB_CTRL_USB_EN); } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
