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.c...@windriver.com>
---
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
--
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