Re: [linux-pm] [RFC,PATCHv3 0/3] sdhci runtime_pm implementation

[Alan Stern]

On Tue, 1 Mar 2011, Pierre Tardy wrote:

> >> > Other drivers do it, but they use PCI PME# instead of interrupts.
> >> Could you please elaborate?
> >> My understanding is that PCI PME will generate MSI, which translate in
> >> interrupt.
> >
> > It depends on the platform.  On systems with ACPI, PCI PME generates an
> > ACPI I/O event, which is handled by the ACPI and PM cores.  It does not
> > invoke the device driver's interrupt handler.
> So, let's say, in the ACPI case, if the interrupt handler dont get
> called, how would the driver know that he got a sdcard insert event,
> and trigger a mmc_rescan() ?

When the ACPI and PCI cores process the PME event, they call
pm_runtime_resume().  The driver's runtime_resume routine would read
the device status and see the insert event, which would cause it to
trigger mmc_rescan().

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/