On Mon, Mar 4, 2019 at 4:35 AM Chen Yu <chenyu56@xxxxxxxxxx> wrote: > On 2019/3/3 0:01, Andy Shevchenko wrote: > > On Sat, Mar 2, 2019 at 11:05 AM Yu Chen <chenyu56@xxxxxxxxxx> wrote: > >> +config HISI_HIKEY_USB > >> + tristate "USB functionality of HiSilicon Hikey Platform" > >> + depends on OF && GPIOLIB > >> + help > >> + If you say yes here you get support for usb functionality of HiSilicon Hikey Platform. > > > >> +#include <linux/of.h> > > > > It's hard to see why this have > > depends on OF followed by above header inclusion. > > > This driver depends on devicetree, so I add "depends on OF". > But is seems that "#include <linux/of.h>" can be removed after "of_" API > have been removed. Thanks for your reminder! So, it means that technically there is no such dependency, rather administratively. > >> + hisi_hikey_usb->typec_vbus = devm_gpiod_get(dev, "typec-vbus", > >> + GPIOD_OUT_LOW); > > > >> + if (!hisi_hikey_usb->typec_vbus) > >> + return -ENOENT; > > > > Hmm... Is it possible to get NULL pointer from gpiod_get() at all? > > > >> + if (!hisi_hikey_usb->otg_switch) > >> + return -ENOENT; > > > > Ditto. > > > I check the comments of devm_gpio_get API, it will not return NULL pointer. > But is it more safe to keep the NULL checking? What is your advice? Why do we need dead code? -- With Best Regards, Andy Shevchenko