> From: Felipe Balbi [mailto:balbi@xxxxxx] > Sent: Wednesday, March 06, 2013 2:36 AM > To: Paul Zimmerman; Kishon Vijay Abraham I; Linux USB Mailing List > Subject: dwc3 PHY autosuspend feature > > Hi Paul, > > Kishon has uncovered a possible 'situation' with dwc3 which we need to > clear up. > > According to your commit 802fde98 (usb: dwc3: support new revisions of > DWC3 core), we don't need to suspend/resume the PHYs at all with any > version > 1.94a, but what we observe is that SUSPHY bits are never set. > > What does that mean ? Would PHY autosuspend be an optional feature by > any chance ? Also, I can't find anywhere in the databook saying that > fiddling with SUSPHY should be avoided due to core IP controlling that > automatically. > > Can you enlighten us ? You still need to set the SusPHY bits, but you only need to do it once. After that, the core will take care of suspending/resuming the PHYs at the right time. You will not see the SusPHY bits changing, though. Actually, for GUSB2PHYCFG.SusPHY you can't just set it once. You need to clear it before any register operation that is marked in the databook with the note "If GUSB2PHYCFG[6] is set to '1', it must be set to '0' prior to issuing this command and may be set to '1' after the command completes". Then when the operation completes you can set it back to 1. -- Paul -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
