Re: [PATCH v5 4/5] usb: host: Stops USB controller init if PLL fails to lock

[Alan Stern]

On Wed, 8 May 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>
> ---
> Change in v5:
> 		use dev_warn() instead of pr_warn()
> 
>  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 1634ac8..90550a6 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) {
> +			dev_warn(dev, "USB PHY clock invalid\n");
> +			return -EINVAL;
> +		}
> +

You need to add a "Fall through" comment between these two cases.

>  	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

Alan Stern