On 05/07/2019 14:44, Pawel Laszczak wrote: > >> EXTERNAL MAIL >> >> >> >> Hi, >> >> Pawel Laszczak <pawell@xxxxxxxxxxx> writes: >>> diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h >>> index da82606be605..d388a3a5ab7e 100644 >>> --- a/include/linux/usb/ch9.h >>> +++ b/include/linux/usb/ch9.h >>> @@ -70,4 +70,29 @@ extern enum usb_device_speed usb_get_maximum_speed(struct device *dev); >>> */ >>> extern const char *usb_state_string(enum usb_device_state state); >>> >>> +/** >>> + * usb_decode_ctrl - Returns human readable representation of control request. >>> + * @str: buffer to return a human-readable representation of control request. >>> + * This buffer should have about 200 bytes. >>> + * @size: size of str buffer. >>> + * @bRequestType: matches the USB bmRequestType field >>> + * @bRequest: matches the USB bRequest field >>> + * @wValue: matches the USB wValue field (CPU byte order) >>> + * @wIndex: matches the USB wIndex field (CPU byte order) >>> + * @wLength: matches the USB wLength field (CPU byte order) >>> + * >>> + * Function returns decoded, formatted and human-readable description of >>> + * control request packet. >>> + * >>> + * The usage scenario for this is for tracepoints, so function as a return >>> + * use the same value as in parameters. This approach allows to use this >>> + * function in TP_printk >>> + * >>> + * Important: wValue, wIndex, wLength parameters before invoking this function >>> + * should be processed by le16_to_cpu macro. >>> + */ >>> +extern const char *usb_decode_ctrl(char *str, size_t size, __u8 bRequestType, >>> + __u8 bRequest, __u16 wValue, __u16 wIndex, >>> + __u16 wLength); >>> + >> >> where's the stub when !TRACING? > > Right, I will add > #ifdef CONFIG_TRACING > ..... > #endif Can usb_decode_ctrl() be used even when CONFIG_TRACING is not set? If yes then above #ifdefe is not sufficient. You might need to do something like #if defined(CONFIG_TRACING) extern const char *usb_decode_ctrl(..) #else static inline const char *usb_decode_ctrl(..) { return NULL; } #endif -- cheers, -roger Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki