[PATCH v5] usb: core: phy: clean up return value check about devm_of_phy_get_by_index()

[Chunfeng Yun]

Use IS_ERR() instead of IS_ERR_OR_NULL() because devm_of_phy_get_by_index()
never return NULL value;
But still need ignore the error of -ENODEV, for more information, please
refer to:
[0] https://lkml.org/lkml/2018/4/19/88
[1] https://patchwork.kernel.org/patch/10160181/

Signed-off-by: Chunfeng Yun <chunfeng....@mediatek.com>
Reviewed-by: Johan Hovold <jo...@kernel.org>
---
V5: add Reviewed-by: Johan Hovold <jo...@kernel.org>
V4: modify the patch subject suggested by Johan
V3: abandon the ternary operator suggested by Johan
V2: keep the -ENODEV check
---

 drivers/usb/core/phy.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c
index 9879767..38b2c77 100644
--- a/drivers/usb/core/phy.c
+++ b/drivers/usb/core/phy.c
@@ -23,10 +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)
+       phy = devm_of_phy_get_by_index(dev, dev->of_node, index);
+       if (IS_ERR(phy)) {
+               if (PTR_ERR(phy) == -ENODEV)
                        return 0;
                else
                        return PTR_ERR(phy);
-- 
1.9.1