Hello Chunfeng, thank you for the patch! On Fri, Jun 22, 2018 at 8:33 AM Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote: > > 1. use IS_ERR() but not IS_ERR_OR_NULL() because devm_of_phy_get_by_index() > never return NULL value; ACK - good catch! > 2. devm_of_phy_get_by_index() should not fail for a valid index I have learned that the PHY framework can return -ENODEV if the PHY is: 1. supposed to be handled by the legacy USB PHY framework 2. the PHY node is disabled in devicetree see [0] for the code in the PHY framework and [1] for the discussion with Johan (who informed me of case #1, I added him on this mail) > Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> > --- > drivers/usb/core/phy.c | 11 ++++------- > 1 file changed, 4 insertions(+), 7 deletions(-) > > diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c > index 9879767..0f972e1 100644 > --- a/drivers/usb/core/phy.c > +++ b/drivers/usb/core/phy.c > @@ -23,14 +23,11 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index, > struct list_head *list) > { > struct usb_phy_roothub *roothub_entry; > - struct phy *phy = devm_of_phy_get_by_index(dev, dev->of_node, index); > + struct phy *phy; > > - if (IS_ERR_OR_NULL(phy)) { > - if (!phy || PTR_ERR(phy) == -ENODEV) > - return 0; > - else > - return PTR_ERR(phy); > - } > + phy = devm_of_phy_get_by_index(dev, dev->of_node, index); > + if (IS_ERR(phy)) > + return PTR_ERR(phy); @Johan can you please review this as well? maybe we need to keep the -ENODEV check Regards Martin [0] https://elixir.bootlin.com/linux/v4.18-rc2/source/drivers/phy/phy-core.c#L421 [1] https://lkml.org/lkml/2018/4/19/88 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html