From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bin Liu Subject: Re: [PATCH 02/10] usb: musb: Fix idling after host mode by increasing autosuspend delay Date: Thu, 5 May 2016 12:47:42 -0500 Message-ID: <20160505174742.GF22575@uda0271908> References: <1461864800-29979-1-git-send-email-tony@atomide.com> <1461864800-29979-3-git-send-email-tony@atomide.com> <20160505150159.GA25950@uda0271908> <20160505170439.GX5995@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Content-Disposition: inline In-Reply-To: <20160505170439.GX5995-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tony Lindgren Cc: Felipe Balbi , linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-omap@vger.kernel.org Hi, On Thu, May 05, 2016 at 10:04:39AM -0700, Tony Lindgren wrote: > * Bin Liu [160505 08:04]: > > Hi, > > > > On Thu, Apr 28, 2016 at 10:33:12AM -0700, Tony Lindgren wrote: > > > Looks like at least 2430 glue won't idle reliably with the 200 ms > > > autosuspend delay. This causes deeper idle states being blocked for > > > the whole SoC when disconnecting OTG A cable. > > > > > > Increasing the delay to 500 ms seems to idle both MUSB and the PHY > > > reliably. This is probably because of time needed by the hardware > > > based negotiation between MUSB and the PHY. > > > > Unless we know other glues also have the same issue, this change > > affects other glues, right? Can we just increase it for 2430 only? > > Well it's hard to say with no PM working with other glue layers right > now. I would not be suprised if similar issue exists with other phys Right. > too talking with musb. > > Does the current 200 ms autosuspend timeout relate to anything real > other than what I found out with my measurements? Not sure, I didn't checkk where the 200ms comes from. > > If there's no other data available for the 200 ms timeout, I suggest > we just set it to 500 ms and add comments there that at least 2430 > glue needs that. If things are not idling properly for the whole > SoC because musb, the power consumption will be way worse than any > power savings between 200 and 500 ms :) Yeah, make sense. > > BTW, I noticed 300 ms did not make a difference there, and 500 ms > seems to work so far. > > Regards, > > Tony Regards, -Bin. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html