> > > Hi, > > There is some inconsistency in remote wakeup functionality in my > > custom board. so I want to wakeup the runtime suspended USB host > > through interrupt. My USB device is connected to the board through USB > > interface and some gpios. device will give interrupt on processor gpio > > when it needs attention of USB host. What should i do so that i can > > wakeup the usb host when i get interrupt from the device. > > Have your gpio interrupt handler call pm_request_resume() for the host > controller device. > > However, this may not do what you want. Since the root hub will remain > suspended, the host controller will go back to low-power immediately > after it is resumed. You really need to resume the USB device itself, > not the host controller. > I think it is the same we echo on > ../power/control, you may need to request gpio interrupt at your usb class driver, and call pm_runtime_get() when the gpio interrupt is coming. After the device finishes using usb, it can call pm_runtme_put through gpio interrupt. Peter > > My idea was to apply power management related hooks from the interrupt > > handler, but I am not getting the clear idea. > > > > My main doubt is, > > Will this mechanism be efficient as remote wakeup functionality? > > That's a hard question to answer without measurements. But it shouldn't > matter, because you probably won't get more than one wakeup per second, > right? > > Alan Stern > > -- > 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 > -- 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
