Messages in this thread | | | Date | Fri, 12 May 2017 10:21:35 -0700 | From | Tony Lindgren <> | Subject | Re: [PATCH] usb-musb: keep VBUS on when device is disconnected |
| |
* Bin Liu <b-liu@ti.com> [170512 08:24]: > On Fri, May 12, 2017 at 07:58:49AM -0700, Tony Lindgren wrote: > > OK. No better ideas except I think we should probably have a separate > > timer for keeping VBUS on after state changes eventually. > > Currently with the patch below, VBUS is constantly on for host-only > mode, and this is what we want. Why we need a separate timer? No one > cuts VBUs now for host-only mode.
Oh I was just thinking what we might want to do in the future if we want to cut off VBUS when no devices are connected. If we have a USB modem for example it might first enumerate as some boot device, then nothing for 20 seconds while it's booting, and then we have a different device enumerating after the modem has booted. During this period we want to keep VBUS on and will go through multiple OTG_STATE_A_WAIT_BCON states. So we can't really control VBUS using the OTG_STATE_WHATEVER alone.
Regards,
Tony
| |