[PATCH v8 4/5] usb: host: Stops USB controller init if PLL fails to lock

From: Yinbo Zhu
Date: Mon Jun 24 2019 - 03:20:39 EST


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 v2:
replace Yinbo.Zhu with Yinbo Zhu.
Change in v5:
add the erratum commont replace "/* fall through */".
Change in v6:
remove "/* fall through */".
Change in v7:
keep v5 change.
Change in v8:
Add "/* fall through */" for case FSL_USB2_PHY_UTMIII.


drivers/usb/host/ehci-fsl.c | 9 +++++++++
drivers/usb/host/fsl-mph-dr-of.c | 3 ++-
2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 8f3bf3efb038..9e9c232e896f 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -236,6 +236,15 @@ static int ehci_fsl_setup_phy(struct usb_hcd *hcd,
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;
+ }
+ /* fall through */
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