> -----Original Message----- > From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx] > Sent: 2019年6月5日 22:22 > To: Yinbo Zhu <yinbo.zhu@xxxxxxx> > Cc: Xiaobo Xie <xiaobo.xie@xxxxxxx>; Greg Kroah-Hartman > <gregkh@xxxxxxxxxxxxxxxxxxx>; Ramneek Mehresh > <ramneek.mehresh@xxxxxxxxxxxxx>; Nikhil Badola > <nikhil.badola@xxxxxxxxxxxxx>; Ran Wang <ran.wang_1@xxxxxxx>; > linux-usb@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Jiafei Pan > <jiafei.pan@xxxxxxx> > Subject: [EXT] Re: [PATCH v6 4/5] usb: host: Stops USB controller init if PLL fails to > lock > > Caution: EXT Email > > On Wed, 5 Jun 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 v6: > > add a "Fall through" comment > > > > drivers/usb/host/ehci-fsl.c | 10 +++++++++- > > drivers/usb/host/fsl-mph-dr-of.c | 3 ++- > > 2 files changed, 11 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c > > index 8f3bf3efb038..86ae37086a74 100644 > > --- a/drivers/usb/host/ehci-fsl.c > > +++ b/drivers/usb/host/ehci-fsl.c > > @@ -234,8 +234,16 @@ static int ehci_fsl_setup_phy(struct usb_hcd *hcd, > > break; > > case FSL_USB2_PHY_UTMI_WIDE: > > 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; > > + } > > + > > case FSL_USB2_PHY_UTMI_DUAL: > > > 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 > Hi Alan Stern, > > Your meaning is to remove "/* fall through*/" or add the erratum commont replace "/* fall through*/" > > Regards, > Yinbo > This is bad. You got rid of a "fall through" comment that was needed, and you > failed to add another one where it was needed. > > Alan Stern I don't get your meaning. Yinbo > > > /* 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 > >
