Re: [PATCH v3 3/5] usb: host: Stops USB controller init if PLL fails to lock

[Alan Stern]

On Wed, 23 Jan 2019, Yinbo Zhu wrote:

> 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>
> ---
>  drivers/usb/host/ehci-fsl.c      |    5 +++++
>  drivers/usb/host/fsl-mph-dr-of.c |    4 ++++
>  2 files changed, 9 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
> index 8b0f3ed..e276067 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");

As before, use dev_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..bdc8812 100644
> --- a/drivers/usb/host/fsl-mph-dr-of.c
> +++ b/drivers/usb/host/fsl-mph-dr-of.c
> @@ -230,6 +230,10 @@ static int fsl_usb2_mph_dr_of_probe(struct platform_device *ofdev)
>  	else
>  		pdata->has_fsl_erratum_14 = 0;
>  
> +	if (of_get_property(np, "fsl,erratum_a006918", NULL))
> +		pdata->has_fsl_erratum_a006918 = 1;
> +	else
> +		pdata->has_fsl_erratum_a006918 = 0;
>  
>  	/*
>  	 * Determine whether phy_clk_valid needs to be checked
>