Re: [PATCH v4 4/5] usb: host: Stops USB controller init if PLL fails to lock

[Alan Stern]

On Fri, 25 Jan 2019, Yinbo Zhu wrote:

> From: Ramneek Mehresh 
> 
> 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 
> Signed-off-by: Suresh Gupta 
> Signed-off-by: Yinbo Zhu 
> ---
>  drivers/usb/host/ehci-fsl.c  |5 +
>  drivers/usb/host/fsl-mph-dr-of.c |3 ++-
>  2 files changed, 7 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
> index 373a816..8b47277 100644
> --- a/drivers/usb/host/ehci-fsl.c
> +++ b/drivers/usb/host/ehci-fsl.c
> @@ -236,6 +236,11 @@ static int ehci_fsl_setup_phy(struct usb_hcd *hcd,
>   portsc |= PORT_PTS_PTW;
>   /* fall through */
>   case FSL_USB2_PHY_UTMI:
> + if (pdata->has_fsl_erratum_a006918) {
> + pr_warn("fsl-ehci: USB PHY clock invalid\n");

Again, you should use dev_warn() instead of pr_warn().

Alan Stern

> + 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 4f8b8a0..762b976 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
> 

[PATCH v4 4/5] usb: host: Stops USB controller init if PLL fails to lock

[Yinbo Zhu]

From: Ramneek Mehresh 

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 
Signed-off-by: Suresh Gupta 
Signed-off-by: Yinbo Zhu 
---
 drivers/usb/host/ehci-fsl.c  |5 +
 drivers/usb/host/fsl-mph-dr-of.c |3 ++-
 2 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 373a816..8b47277 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -236,6 +236,11 @@ static int ehci_fsl_setup_phy(struct usb_hcd *hcd,
portsc |= PORT_PTS_PTW;
/* fall through */
case FSL_USB2_PHY_UTMI:
+   if (pdata->has_fsl_erratum_a006918) {
+   pr_warn("fsl-ehci: 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 4f8b8a0..762b976 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
-- 
1.7.1