RE: [PATCH v1 3/6] usb: host: Stops USB controller init if PLL fails to lock

From: Yinbo Zhu
Date: Mon Jan 21 2019 - 05:09:07 EST




-----Original Message-----
From: Sergei Shtylyov [mailto:sergei.shtylyov@xxxxxxxxxxxxxxxxxx]
Sent: 2019å1æ21æ 16:17
To: Yinbo Zhu <yinbo.zhu@xxxxxxx>; Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Cc: Xiaobo Xie <xiaobo.xie@xxxxxxx>; Jerry Huang <jerry.huang@xxxxxxx>; Ran Wang <ran.wang_1@xxxxxxx>; Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; Ramneek Mehresh <ramneek.mehresh@xxxxxxxxxxxxx>; Nikhil Badola <nikhil.badola@xxxxxxxxxxxxx>; Suresh Gupta <suresh.gupta@xxxxxxxxxxxxx>; linux-usb@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH v1 3/6] usb: host: Stops USB controller init if PLL fails to lock

>Hello!

> On 21.01.2019 6:13, Yinbo Zhu wrote:

> From: yinbo.zhu <yinbo.zhu@xxxxxxx>
>
> 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 | 5 +++++
> 2 files changed, 10 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
> index a28ec1e..6884130 100644
> --- a/drivers/usb/host/ehci-fsl.c
> +++ b/drivers/usb/host/ehci-fsl.c
> @@ -224,6 +224,11 @@ 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 677f9d5..7e07701 100644
> --- a/drivers/usb/host/fsl-mph-dr-of.c
> +++ b/drivers/usb/host/fsl-mph-dr-of.c
> @@ -225,6 +225,11 @@ static int fsl_usb2_mph_dr_of_probe(struct platform_device *ofdev)
> pdata->has_fsl_erratum_a005697 =
> of_property_read_bool(np, "fsl,usb_erratum-a005697");
>
> + if (of_get_property(np, "fsl,erratum_a006918", NULL))

> of_property_read_bool() perhaps?

Hi Sergei,

[PATCH v1 6/6] had modified it as this string format,
Please you note.

MBR, Yinbo
> + pdata->has_fsl_erratum_a006918 = 1;
> + else
> + pdata->has_fsl_erratum_a006918 = 0;
> +
> /*
> * Determine whether phy_clk_valid needs to be checked
> * by reading property in device tree

> MBR, Sergei