[PATCH v6 4/5] usb: host: Stops USB controller init if PLL fails to lock

[Yinbo Zhu]

From: Ramneek Mehresh <ramneek.mehresh@xxxxxxxxxxxxx>

USB erratum-A006918 workaround tries to start internal PHY inside
uboot (when PLL fails to lock). However, if the workaround also
fails, then USB initialization is also stopped inside Linux.
Erratum-A006918 workaround failure creates "fsl,erratum_a006918"
node in device-tree. Presence of this node in device-tree is
used to stop USB controller initialization in Linux

Signed-off-by: Ramneek Mehresh <ramneek.mehresh@xxxxxxxxxxxxx>
Signed-off-by: Suresh Gupta <suresh.gupta@xxxxxxxxxxxxx>
Signed-off-by: Yinbo Zhu <yinbo.zhu@xxxxxxx>
---
Change in v6:
		add a "Fall through" comment 	

 drivers/usb/host/ehci-fsl.c      | 10 +++++++++-
 drivers/usb/host/fsl-mph-dr-of.c |  3 ++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 8f3bf3efb038..86ae37086a74 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -234,8 +234,16 @@ static int ehci_fsl_setup_phy(struct usb_hcd *hcd,
 		break;
 	case FSL_USB2_PHY_UTMI_WIDE:
 		portsc |= PORT_PTS_PTW;
-		/* fall through */
 	case FSL_USB2_PHY_UTMI:
+		/* Presence of this node "has_fsl_erratum_a006918"
+		 * in device-tree is used to stop USB controller
+		 * initialization in Linux
+		 */
+		if (pdata->has_fsl_erratum_a006918) {
+			dev_warn(dev, "USB PHY clock invalid\n");
+			return -EINVAL;
+		}
+
 	case FSL_USB2_PHY_UTMI_DUAL:
 		/* PHY_CLK_VALID bit is de-featured from all controller
 		 * versions below 2.4 and is to be checked only for
diff --git a/drivers/usb/host/fsl-mph-dr-of.c b/drivers/usb/host/fsl-mph-dr-of.c
index 4f8b8a08c914..762b97600ab0 100644
--- a/drivers/usb/host/fsl-mph-dr-of.c
+++ b/drivers/usb/host/fsl-mph-dr-of.c
@@ -224,13 +224,14 @@ static int fsl_usb2_mph_dr_of_probe(struct platform_device *ofdev)
 		of_property_read_bool(np, "fsl,usb-erratum-a005275");
 	pdata->has_fsl_erratum_a005697 =
 		of_property_read_bool(np, "fsl,usb_erratum-a005697");
+	pdata->has_fsl_erratum_a006918 =
+		of_property_read_bool(np, "fsl,usb_erratum-a006918");
 
 	if (of_get_property(np, "fsl,usb_erratum_14", NULL))
 		pdata->has_fsl_erratum_14 = 1;
 	else
 		pdata->has_fsl_erratum_14 = 0;
 
-
 	/*
 	 * Determine whether phy_clk_valid needs to be checked
 	 * by reading property in device tree
-- 
2.17.1