Re: [PATCH 4/4] mfd: global Suspend and resume support of ehci andohci

From: Alan Stern
Date: Wed Jun 29 2011 - 13:33:36 EST


On Wed, 29 Jun 2011, Munegowda, Keshava wrote:

> for usb host case , I am seeing that the pm_runtime_get_sync
>
>
> static int rpm_resume(struct device *dev, int rpmflags)
> {
> ............
> ..........
> if (dev->pwr_domain) {
> callback = dev->pwr_domain->ops.runtime_resume;
> if(!strcmp(dev_name(dev),"usbhs_omap"))
> pr_err("dev->pwr_domain->ops.runtime_resume");
> }
> else if (dev->type && dev->type->pm) {
> callback = dev->type->pm->runtime_resume;
> if(!strcmp(dev_name(dev),"usbhs_omap"))
> pr_err("dev->type->pm->runtime_resume");
> }
> else if (dev->class && dev->class->pm) {
> callback = dev->class->pm->runtime_resume;
> if(!strcmp(dev_name(dev),"usbhs_omap"))
> pr_err("ev->class->pm->runtime_resume");
> }
> else if (dev->bus && dev->bus->pm) {
> callback = dev->bus->pm->runtime_resume;
> if(!strcmp(dev_name(dev),"usbhs_omap"))
> pr_err("dev->bus->pm->runtime_resume");
> }
> else
> callback = NULL;
> }
>
>
> I am seeing that below if statement was hitting true:
>
> if (dev->pwr_domain) {
> callback = dev->pwr_domain->ops.runtime_resume;
> if(!strcmp(dev_name(dev),"usbhs_omap"))
> pr_err("dev->pwr_domain->ops.runtime_resume");
>
>
> due to this; the driver->runtime_resume was not getting called.
>
> Any idea on why I am seeing only the dev->pwr_domain is set not
> dev->bus && dev->bus->pm is hitting here?

Because the PM domain takes precedence over the subsystem for PM
callbacks. If the subsystem routine should be called then the PM
domain code has to call it.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/