NeilBrown <neilb@xxxxxxx> writes: > On Tue, 12 Feb 2013 13:03:36 -0800 Kevin Hilman <khilman@xxxxxxxxxx> wrote: > >> NeilBrown <neilb@xxxxxxx> writes: >> [...] >> My patch was fixing a real hang when musb was built-in (or loaded), in >> host-mode (mini-A cable attached) but no devices attached. I just tried >> to reproduce this, and with your patch, the system hangs during suspend. >> > > Odd. I plug in a mini-A cable, note that the 'mode' file holds > 'a_idle' (sometimes just plugging in the cable isn't enough to trigger that, > but sometimes it is....) and suspend/resume work perfectly. Though after > resume it is back to b_idle. > > unplug/replug and it is back to a_idle. suspend/resume and back to b_idle. > >> That being said, your description makes sense why this context >> save/restore is needed. Perhaps your patch needs to add a check whether >> the device is runtime suspended (I gather this is what Ruslan's patch is >> doing.) > > I'm not sure it is possible for the device to be runtime suspended at this > point. Certainly my device never is, even if it was just before the suspend > sequence started. Something is waking it up... > (instruments the code). > > Ahh - usb_suspend() calls choose_wakeup() which might call > pm_runtime_resume() if the could be a need to reprogram the wakeup setting. > As that is a 'might', the device might not be runtime-awake when 'suspend' > runs. > > Can you see if this, on top of my previous patch, does any better on your > hardware? Yes, this patch adding the check on top of your previous one makes things work just fine on my hardware (3530/Overo). Kevin > Thanks, > NeilBrown > > > diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c > index 956db0e..00deb94 100644 > --- a/drivers/usb/musb/musb_core.c > +++ b/drivers/usb/musb/musb_core.c > @@ -2278,7 +2278,8 @@ static int musb_suspend(struct device *dev) > } > > spin_unlock_irqrestore(&musb->lock, flags); > - musb_save_context(musb); > + if (!pm_runtime_status_suspended(dev)) > + musb_save_context(musb); > return 0; > } > > @@ -2289,7 +2290,8 @@ static int musb_resume_noirq(struct device *dev) > * module got reset through the PSC (vs just being disabled). > */ > struct musb *musb = dev_to_musb(dev); > - musb_restore_context(musb); > + if (!pm_runtime_status_suspended(dev)) > + musb_restore_context(musb); > return 0; > } > -- 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
