On Thu, 20 Jun 2019, Mayuresh Kulkarni wrote: > > It would be easiest to export the usb_autopm_* API to user space. > > AFAIU, usb_autopm_* API operate on interface rather than on device. > Due to this, they are *indirectly* exposed by appropriate class drivers > to the user-space class drivers cater to. E.g.: USB audio class driver > calls usb_autopm_* APIs when user space calls pcm_open(playback_stream). In fact, the usb_autopm_* API can operate both on interfaces and on devices. It is used both ways in the kernel. Alan Stern