On 29 November 2017 at 09:21, Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> wrote: > Hi, > >> From: Ulf Hansson, Sent: Wednesday, November 29, 2017 2:23 AM >> >> On 28 November 2017 at 13:48, Yoshihiro Shimoda >> <yoshihiro.shimoda.uh@xxxxxxxxxxx> wrote: >> > Hi Geert-san, >> > >> >> From: Geert Uytterhoeven, Sent: Tuesday, November 28, 2017 7:58 PM >> >> >> >> Hi Rafael, Shimoda-san, >> >> >> >> On Sun, Nov 12, 2017 at 1:27 AM, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote: >> >> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > <snip> >> >> JFTR, this triggered before during system resume on e.g. Salvator-XS with >> >> R-Car H3: >> >> >> >> ohci-platform ee080000.usb: runtime PM trying to suspend device >> >> but active child >> >> phy_rcar_gen3_usb2 ee080200.usb-phy: runtime PM trying to suspend >> >> device but active child >> >> ohci-platform ee0c0000.usb: runtime PM trying to suspend device >> >> but active child >> >> ohci-platform ee0a0000.usb: runtime PM trying to suspend device >> >> but active child >> >> phy_rcar_gen3_usb2 ee0c0200.usb-phy: runtime PM trying to suspend >> >> device but active child >> >> phy_rcar_gen3_usb2 ee0a0200.usb-phy: runtime PM trying to suspend >> >> device but active child >> >> >> >> so this was an existing issue with USB before. >> > >> > Thank you for the report! >> > I know that, but since this didn't cause any trouble until now, >> > I postponed to investigate the issue... But, I investigate it today. >> > I don't find the root cause yet. However, it seems related to usb host and/or usb core. >> > --> USB host related devices' child_count will be 1 in suspend timing. >> > --> I guess remote wakeup feature is enabled? But, I don't find the point yet. >> >> I am guessing the issue is triggered by genpd in the suspend noirq >> phase (genpd_suspend_noirq()). In there, there is a call to >> pm_runtime_force_suspend() (which calls pm_runtime_set_suspended() and >> which triggered the earlier error messages being printed). >> >> The reason why genpd calls pm_runtime_force_suspend(), is because when >> validating wakeup configurations for the device "if >> (dev->power.wakeup_path && genpd_is_active_wakeup(genpd))", it's >> thinks wakeup isn't configured while it probably should be. >> >> An additional note, only when genpd has the GENPD_FLAG_PM_CLK set, >> which makes the genpd->dev_ops.stop|start() being assigned, genpd >> calls pm_runtime_force_suspend() - else it doesn't. >> >> Perhaps try out the series I recently posted improving the code >> dealing with wakeups in genpd and the PM core: >> https://www.spinics.net/lists/linux-renesas-soc/msg20122.html >> To that, you need to set the new flag (invented in the above series) >> DPM_FLAG_IN_BAND_WAKEUP in the driver that configures wakeup of its >> device. >> >> Hope this helps! > > Thank you for the comments! > I tried DPM_FLAG_IN_BAND_WAKEUP, but the issue still exists. > I added the flag in the [eo]hci-platform driver and usb/core/driver.c. > I also added the flag in the phy_rcar_gen3_usb2 driver except usb host drivers. First, did you confirm that genpd was used? Then for what device? Second, did you check the call to pm_runtime_force_suspend() called by genpd, is the reason to the error messages? Third, it should be sufficient to add DPM_FLAG_IN_BAND_WAKEUP for the driver that is actually dealing with the wakeup. Although, does this driver's system ->suspend() callback check device_may_wakeup(), before it decides to enable wakeup? If not, the PM core and genpd don't notice that wakeup is enabled for the device. > >> > The renesas_usbhs also uses the phy_rcar_gen3_usb2 driver. >> > --> If I only used the renesas_usbhs driver (in other words, I don't install >> > [eo]hci-{hcd,platform} drivers), the issue disappeared. >> > --> So, I think the phy_rcar_gen3_usb2 driver doesn't cause this issue. >> > (But, it is possible to be related though.) >> > >> > I'll continue to investigate this issue tomorrow. >> >> Please keep me posted, I am interested about the why the problem exists. :-) > > Sure! :) Great, thanks. Kind regards Uffe
